AFP
Alpha-fetoprotein precursor (Alpha-1-fetoprotein) (Alpha-fetoglobulin) [HPAFP]
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Alpha-fetoprotein (AFP) is one of the best-known embryo-specific proteins. It is used to diagnose fetal abnormalities and tumors of the gastrointestinal tract and liver. AFP has pronounced immunotropic and detoxifying effect and a direct apoptotic effect on tumor cells. The treatment of mice at the oldest age in our experiments with AFP dramatically increased the survival and markedly increased the relative weight of immunotropic organs, apparently due to the general effect of AFP in improving functions of tissues and detoxifying actions. It also improved appearance and the relative weight of internal organs with a reduced age of autoaggression.
MeSH Terms
- Aging
- Animals
- Drug Evaluation, Preclinical
- Female
- Injections, Intraperitoneal
- Longevity
- Mice, Inbred BALB C
- alpha-Fetoproteins
Vitamin D levels play a pivotal role in most biological processes and differ according to age. A deficiency of vitamin D in chronic hepatitis C (CHC) patients has been shown to be linked with the severity of liver fibrosis, but little is known about the mechanism of this association. In this study, we evaluate the potential interrelation between vitamin D levels, oxidative stress, and apoptosis, based on liver fibrosis in geriatric patients infected with hepatitis C virus (HCV) genotype 4. A total of 120 adult individuals aged 30-68 years were recruited in this study. Of these, 20 healthy subjects (15 men and five women) with a mean age of 48.3±6.1 years were selected as controls, and 100 patients with a mean age of 47.8±4.9 years with chronic HCV (CHC) who had undergone liver biopsy (80 men and 20 women) were included in this study. Based on liver radiographic (computed tomography, magnetic resonance imaging) and histological Metavir system analyses, the CHC patients were classified into three groups: asymptomatic CHC carriers (n=30), fibrosis (n=25), and cirrhosis (n=45). HCV RNA, HCV genotypes, inflammatory cytokines AFP and TNFα, 25-hydroxyvitamin D (25[OH]D) levels, apoptotic markers single-stranded DNA (ssDNA) and soluble Fas (sFas), and oxidative stress markers nitric oxide (NO) and total antioxidant capacity (TAC) were estimated by using molecular, immunoassay, and colorimetric techniques. Approximately 30% of the study population (n=30) were diagnosed as asymptomatic CHC carriers, and 70% of the study population (n=70) had severe fibrosis; these were classified into fibrosis and cirrhosis. There was a significant reduction in 25(OH)D levels and TAC activity, along with an increase in levels of NO, AFP, TNFα, ssDNA, and sFas in fibrosis and cirrhosis subjects compared with those of asymptomatic CHC carriers and health controls. The deficiency in 25(OH)D levels correlated positively with sFas, ssDNA, AFP, TNFα, NO, and TAC, and negatively with age, sex, liver function, body mass index, homeostatic model assessment - insulin resistance, HCV RNA, and viral load. Significant intercorrelation was reported between serum 25(OH)D concentrations and apoptotic and oxidative markers, which suggested progression of liver pathogenesis and fibrogenesis via oxidative and apoptotic mechanisms. The data showed that vitamin D status was significantly correlated with pathogenesis and fibrogenesis of the liver in geriatric patients infected with HCV genotype 4. The deficiency in 25(OH)D levels was shown to have a pivotal role in the pathogenesis of liver via apoptotic, oxidative stress, and inflammatory mechanistic pathways. The data point to adequate vitamin D levels being recommended for a good response to treatment strategies, especially in older CHC patients.
MeSH Terms
- Adult
- Aged
- Apoptosis
- Biomarkers
- Female
- Genotype
- Hepacivirus
- Hepatitis C, Chronic
- Humans
- Insulin Resistance
- Liver Cirrhosis
- Male
- Middle Aged
- Oxidative Stress
- Vitamin D
Keywords
- 25(OH)D
- Fas antigen
- HCV
- apoptosis
- geriatrics
- liver fibrosis
- oxidative stress
The majority of chronic diseases in the aging adult are thought to relate to immune aging characterized by dominant immunosuppression and paradoxically, concomitant inflammation. This is known collectively as immunosenescence. The main change thought to be controlling immune aging is the age-related decline in dehydroepiandrosterone (DHEA) and corresponding increase in cortisol; the net effect which decreases the DHEA/cortisol ratio. Exactly how this translates to immunosuppression and concomitant inflammation remains unclear. Recently a new component of the human innate immune system has been discovered. Human endogenous retrovirus K102 (HERV-K102) is a replication-competent foamy retrovirus unique to humans which has been implicated in chronic diseases. Accumulating evidence suggests that HERV-K102 may defend the host against viral infections, as well as against breast and other cancers. Particles are produced in activated monocytes and released into vacuoles but do not bud through the cell surface. This renders macrophages foamy, while the release of particles is only through cell lysis. New evidence presented here suggests DHEA but not DHEA-S may specifically bind and inactivate alpha-fetoprotein (AFP). AFP is a well-established immunosuppressive factor which importantly, also blocks cell lysis induction in macrophages through the 67 kilodalton (kD) AFP receptor (AFPr). Here, it is proposed that a decreased DHEA/cortisol ratio may favor the accumulation of foamy macrophages reflecting the cortisol induction of HERV-K102 particle production concomitant with the blocked release of particles by secreted AFP. This is a new paradigm to explain how cortisol-mediated immunosenescence can result in the persistence of foamy macrophages, and how this relates to risk of chronic disease.
MeSH Terms
- Aging
- Chronic Disease
- Endogenous Retroviruses
- Humans
- Hydrocortisone
- Immunosenescence
- Risk Factors
- Virion
The frailty phenotype (FP) proposed by Fried and colleagues (Fried LP, Tangen CM, Walston J, et al.; Cardiovascular Health Study Collaborative Research Group. Frailty in older adults: evidence for a phenotype. J Gerontol A Biol Sci Med Sci. 2001;56:M146-M156.) requires the administration of performance tests (gait speed, handgrip strength) not always feasible in routine clinical practice. Furthermore, the discriminative capacity of the instrument has been rarely investigated. Aim of this study was to evaluate the discriminative capacity of the FP and compare it with a modified version including only anamnestic information. Data are from 890 participants of the InCHIANTI study without impairment in activities of daily living (ADL) at baseline (mean age 74 years, women 55%). Frailty was defined by (a) the presence of ≥ 3 criteria of the FP, and (b) having ≥ 2 criteria of an anamnestic FP (AFP), not including gait speed and handgrip strength. Sensitivity, specificity, positive and negative predictive values (PPV, NPV) were used to evaluate the discriminative capacity of both definitions for incident disability (ie, loss of at least one ADL), incidence of "accelerated" disability (loss of >2 ADL) over a 6-year follow-up, and 5-years mortality. FP and AFP yielded a frailty prevalence of 6.4% and 6.5%, respectively; only 32 patients were considered frail by both indices (kappa: .53). For incident disability, FP showed sensitivity = .194, specificity = .963, PPV = .400, and NPV = .903. Similarly, AFP had sensitivity = .129, specificity = .949, PPV = .245, and NPV = .894. Consistent results were found for accelerated disability and mortality. In our sample, both FP and AFP showed low sensitivity in identifying older people who would die or develop disability, but they could well discriminate people who would not experience adverse outcomes.
MeSH Terms
- Activities of Daily Living
- Aged
- Aging
- Disability Evaluation
- Female
- Follow-Up Studies
- Frail Elderly
- Gait
- Geriatric Assessment
- Hand Strength
- Humans
- Italy
- Male
- Predictive Value of Tests
- Psychomotor Performance
- Reproducibility of Results
Keywords
- Disability
- Frailty
- Mortality
- Predictive value
- Sensitivity and specificity.
Biomarkers of the age of mosquitoes are required to determine the risk of transmission of various pathogens as each pathogen undergoes a period of extrinsic incubation in the mosquito host. Using the 2-D Difference Gel Electrophoresis (2-D DIGE) procedure, we investigated the abundance of up to 898 proteins from the Yellow Fever and dengue virus vector, Aedes aegypti, during ageing. By applying a mixed-effects model of protein expression, we identified five common patterns of abundance change during ageing and demonstrated an age-related decrease in variance for four of these. This supported a search for specific proteins with abundance changes that remain tightly associated with ageing for use as ageing biomarkers. Using MALDI-TOF/TOF mass spectrometry we identified ten candidate proteins that satisfied strict biomarker discovery criteria (identified in two out of three multivariate analysis procedures and in two cohorts of mosquitoes). We validated the abundances of the four most suitable candidates (Actin depolymerising factor; ADF, Eukaryotic initiation factor 5A; eIF5A, insect cuticle protein Q17LN8, and Anterior fat body protein; AFP) using semi-quantitative Western analysis of individual mosquitoes of six ages. The redox-response protein Manganese superoxide dismutase (SOD2) and electron shuttling protein Electron transfer oxidoreductase (ETO) were subject to post-translational modifications affecting their charge states with potential effects on function. For the four candidates we show remarkably consistent decreases in abundance during ageing, validating initial selections. In particular, the abundance of AFP is an ideal biomarker candidate for whether a female mosquito has lived long enough to be capable of dengue virus transmission. We have demonstrated proteins to be a suitable class of ageing biomarkers in mosquitoes and have identified candidates for epidemiological studies of dengue and the evaluation of new disease reduction projects targeting mosquito longevity.
MeSH Terms
- Aedes
- Aging
- Animals
- Biomarkers
- Female
- Insect Vectors
- Proteome
- Proteomics
ZENK expression in vocal nuclei is associated with singing behavior. Area X is an important nucleus for learning and stabilizing birdsong. ZENK expression is higher in Area X compared to that in other vocal nuclei when birds are singing. To reveal the relationship between the ZENK expression in Area X and song crystallization, immunohistochemistry was used to detect ZENK protein expression in Area X after the unilateral vocal nerve (tracheosyringeal nerve) section in adult male zebra finches. Sham operations had no effect on song. In contrast, section of unilateral vocal nerve could induce song decrystallization at the 7th day after the surgery. The spectral and the temporal features of birdsong were distorted more significantly in the right-side vocal nerve section than in the left-side vocal nerve section. In addition, after surgery, ZENK expression was higher in the right-side of Area X than in the left-side. These results indicate that the vocal nerve innervations probably are right-side dominant. ZENK expression in both sides of Area X decreased, as compared to control group after surgery, which suggests that the ZENK expression in Area X is related to birdsong crystallization, and that there is cooperation between the Area X in AFP and syrinx nerve.
MeSH Terms
- Aging
- Animals
- Avian Proteins
- Brain
- Early Growth Response Protein 1
- Finches
- Gene Expression Regulation
- Learning
- Male
- Vocalization, Animal
The retrospective cohort study surveys the influence of age, co-morbidity and laboratory values on FVIII-activity (FVIII:C) in patients with haemophilia A with (mild n = 48, moderate n = 10, severe n = 7 and carriers n = 23). Median observation was 19 years for patients with haemophilia A and 9,5 years for carriers. FVIII:C levels collected from patients with mild haemophilia A displayed a significant median increase of 6.5% with proceeding age (p = 0.0013). Patients with moderate haemophilia A (and carriers of haemophilia A) showed a non significant median increase of 1.05% (carriers 8%). Eight patients showed FVIII:C levels at last blood withdrawal that indicated a change of severity from moderate to mild haemophilia A. A significant correlation was found between FVIII:C and VWF:RCo (p = 0.0203) and AFP (p < 0.0005). The correlation between FVIII:C and triglycerides and LDH was significant negative (p < 0.0005). No significant correlation could be found for FVIII:C and co-morbidity, fibrinogen, cholesterol and VWF:Ag.
MeSH Terms
- Adult
- Aging
- Factor VIII
- Female
- Hemophilia A
- Heterozygote
- Humans
- Male
The elevated serum alpha fetoprotein (AFP) concentration in ataxia-telangiectasia (A-T) patients has been known for decades, but the individual variation of AFP levels over time has not been studied. We have followed 12 patients (five girls and seven boys) for 1-12 years (mean 5.5 years) measuring in each patient AFP 2-8 (mean 4) times. Serum AFP levels were increased in all patients, mean 168.7 (range 40-373) kU/L, and without significant differences between the patients. There was a significant age related difference in the serum AFP level. A positive linear relationship (r=0.61, p=0.04) could be found between AFP level and age. Albumin levels were within normal range and did not change with age. Four patients had slightly increased aspartate aminotransferase (AST) levels. None of the patients had serological evidence of infectious hepatitis, and none had increased levels of carcinoembryonic antigen. Repeated standardized observations of gait function revealed no major difference in neurological deterioration between our patients. All had classical A-T disease and mainly truncating mutations; 21 out of 24 possible mutations were either frameshift or nonsense. Four were homozygous for the Norwegian ATM founder mutation. No correlation between serum AFP levels and the different ATM genotypes could be found. We conclude that serum AFP is not only elevated, but also is continuously increasing with age in patients with classical A-T disease.
MeSH Terms
- Aging
- Analysis of Variance
- Aspartate Aminotransferases
- Ataxia Telangiectasia
- Child
- Child, Preschool
- Female
- Frameshift Mutation
- Humans
- Immunoradiometric Assay
- Infant
- Male
- Walking
- alpha-Fetoproteins
To optimise vaccination strategies for immunotherapy in the liver, we have generated a line of transgenic mice expressing beta-Galactosidase downstream of the alpha-fetoprotein promoter (AFP/betaGal). betaGal expression was documented by qRT-PCR, enzyme activity and immunohistochemistry. betaGal-specific CD8 T-cell activation in mice immunised with various vectors was measured by interferon-gamma ELISpot. Like AFP, betaGal expression was detected in fetal hepatocytes and disappeared around birth. In adult mice, a CD8 T-cell response to betaGal was observed after immunisation with betaGal adenovirus or plasmid DNA but not with betaGal protein or after retroviral infection. When betaGal was re-expressed in adult hepatocytes, immunisation with betaGal adenovirus triggered T-cell mediated elimination of betaGal-expressing hepatocytes. However, the response was weaker than in AFP/betaGal animals in which betaGal was only present around birth. In AFP/betaGal mice, betaGal is a fetal liver self-antigen. Interestingly, the basal tolerance to betaGal displayed by these animals is increased during liver re-expression of the self-antigen in adulthood. Adenoviral immunisation allows complete elimination of betaGal-expressing hepatocytes in spite of this increased peripheral tolerance. These results highlight the importance of tolerance against self-antigens and validate the AFP/betaGal mice as a good background to test immunotherapy strategies in hepatocarcinogenesis models.
MeSH Terms
- Adenoviridae
- Aging
- Animals
- Antibody Formation
- Autoantigens
- CD8-Positive T-Lymphocytes
- DNA
- Fetus
- Genetic Vectors
- Hepatocytes
- Immunization
- Immunotherapy
- Liver
- Mice
- Mice, Transgenic
- Plasmids
- Promoter Regions, Genetic
- alpha-Fetoproteins
- beta-Galactosidase
alpha-Fetoprotein (AFP) is often elevated in hepatocellular carcinoma (HCC). This study was to elucidate the significance and related factors of AFP elevation in HCC in 781 unifocal HCCs receiving curative hepatectomy. We showed that high AFP (> 200 ng/ml), which was associated with AFP mRNA expression in HCC (p = 0.00001), correlated with major clinicopathologic factors. Younger age (< or = 55 years; p=0.00001), hepatitis B surface antigen (HBsAg) in serum (p=0.00001), p53 mutation (p=0.008), large tumor (p=0.00001), vascular invasion (p=0.00001) and early tumor recurrence (p=0.00001) were significant associates of high AFP, while anti-HCV in serum and beta-catenin mutation in HCC had less frequent high AFP (p=0.013 and < 0.0001, respectively). We also showed that HCC with high AFP had a lower 10-year survival (p < 0.0001), particularly in large HCC (p < 0.0001). At univariate analysis, high AFP (p < 0.0001), HBsAg positivity (p=0.05), p53 mutation (p=0.0004), liver cirrhosis (p=0.0094), large tumor (p=0.0003), vascular invasion (p < 0.0001) and early recurrence (p < 0.0001) were significant unfavorable prognostic factors. In Cox proportional hazards regression analysis, high AFP remained a borderline significance (OR=1.2; CI=1.0-1.4) after adjustment for the effect of tumor size and tumor stage (p=0.0821). Furthermore, the detection of AFP mRNA in the liver of AFP mRNA-positive HCC was associated with more frequent early recurrence (p=0.0026) and might be a useful marker of intrahepatic spread. We therefore conclude that AFP elevation, more than a coincidental epiphenomenon, appears to contribute to vascular invasion and HCC progression and help to identify subsets of HCC patients with increased risk for early recurrence and poor prognosis after hepatectomy.
MeSH Terms
- Adolescent
- Adult
- Aged
- Aged, 80 and over
- Aging
- Biomarkers, Tumor
- Carcinoma, Hepatocellular
- Child
- Cytoskeletal Proteins
- Female
- Gene Expression Regulation, Neoplastic
- Hepatitis B
- Hepatitis B Surface Antigens
- Humans
- Liver Neoplasms
- Male
- Middle Aged
- Mutation
- Neoplasm Recurrence, Local
- Neoplasm Staging
- Prognosis
- RNA, Messenger
- RNA, Neoplasm
- Reverse Transcriptase Polymerase Chain Reaction
- Trans-Activators
- Tumor Suppressor Protein p53
- alpha-Fetoproteins
- beta Catenin
Hepatocyte proliferation (HP) is an adaptive response to liver injury. The relationships between HP and necroinflammation, fibrosis, and serum alpha-fetoprotein (AFP) levels in chronic hepatitis C virus (HCV) infection, however, are not well understood. Proliferative hepatocytes (Ki-67 ) were identified using immunohistochemical staining in formalin-fixed, paraffin-embedded liver tissue from 156 HCV RNA-positive patients with different degrees of liver histopathology. Twenty high-power fields (HPFs) in lobular areas were counted in each specimen. HP increased by 1.22 /- 0.25 cells/HPF per increase in necroinflammation from grade 0 (median: 0.13; range: [0.1-0.5] cells/HPF) through grade 3 (median: 1.80; range: [0.0-25.2] cells/HPF; P=0.002). HP increased by 0.81 /- 0.20 cells/HPF per increase in fibrosis from stage 0 (median: 0.33; range: [0.0-1.3] cells/HPF) through stage 3 (median: 1.70; range: [0.0-25.2] cells/HPF) and then decreased in stage 4 (to median: 0.90; range: [0.0-5.3] cells/HPF). HP also increased with advancing age (P=0.03). Among patients with advanced liver disease, HP was no higher in patients with elevated serum AFP levels (median: 1.68; range: [0.1-5.3] cells/HPF) than in those with normal serum AFP levels (median: 1.70; range: [0.0-25.2] cells/HPF; P=0.26). In patients with chronic HCV infection, HP increases with histologic progression of liver disease, but is impaired in cirrhosis. HP was not increased in patients with elevated serum AFP levels.
MeSH Terms
- Adult
- Aging
- Cell Division
- Disease Progression
- Female
- Hepatitis C, Chronic
- Hepatocytes
- Humans
- Immunohistochemistry
- Liver Diseases
- Male
- Middle Aged
- Necrosis
- Severity of Illness Index
- alpha-Fetoproteins
An experiment on rat undernutrition through seven generations was performed in order to see: (1) whether the nutritional stress on growth increases from one generation to the next, and (2) if an equilibrium point (AFP) in which the RFI--the amount of food intake (mg) per gram of body weight--reached is the same in both control and undernourished animals. The RFI values were calculated for each generation, between the 30th and 100th days of age. A moderate undernutrition was applied to the seven generations (F1 to F7) following the parental (P) one, which acted as controls. Undernourishment was made from conception to the end of the experiment (100 days old). The RFI values diminished with the age increment and increased through generations. There was, however, a clear AFP of 75.9 /- 3.5 mg/g at 100 days of age in males, and of 78.7 /- 4.2 mg/g at 90 days of age in females. A clear cumulative increment of RFI through the filial generations was also found at intermediate growth ages. The frequently argued nongenetic transmission of the nutritional deficiencies from parents to descendants was corroborated with the present results. Such cumulative effect was evident at ages before the AFP was reached; i.e., when the decrement in body mass of the undernourished animals was not yet equilibrated with the amount of available nutrients.
MeSH Terms
- Aging
- Analysis of Variance
- Animals
- Body Weight
- Eating
- Female
- Growth
- Male
- Nutrition Disorders
- Parents
- Rats
- Rats, Wistar
- Sex Characteristics
- Time Factors
Alpha fetoprotein (C-AFP), serum albumin (C-fSA) from chicken embryos, and SA from hens were purified using gentle chromatographic and electrophoretic methods, and their fatty acids (FAs) and squalene contents were analyzed using gas chromatography and mass spectrometry. In 7-day-old chick embryo, AFP carries 16% and fSA 6% free FAs, the rest being carried as phospholipids, which differs from rat and pig AFP, where all fatty acids are carried like free fatty acids. At this stage C-AFP contains 3.6% arachidonic acid, which falls to 1.7% in 14-day-old embryos. Both of these figures are significantly lower than in humans, rats, calves, and pigs. C-AFP does not transport docosahexaenoic acid, in notable contrast to the mammals mentioned above. The finding of squalene in the two fetal proteins is reported for the first time. During the interval between 7 and 14 days, the proportion of C16:1 n-7 and of C18:2 n-6 increases 10-fold, that of C18:0 quadruples, and that of C18:1 n-9 decreases 3-fold. Squalene increases in this period from 2.2% to 10.0%. The C-fSA of a 7-day-old embryo transports only one FA with more than two unsaturated carbons, arachidonic acid (2.4%). It also contains squalene (1.2%). Similarly, only arachidonic acid (2.5%), but not squalene is found in hen SA. The percentage of saturated and monounsaturated FAs divided by the percentage of polyunsaturated FAs, and the ratios of the percentage of FAs with C14-C18 with respect to those with C20-C22 transported by C-AFP are very different from those of studied mammals.
MeSH Terms
- Aging
- Animals
- Cattle
- Chick Embryo
- Chickens
- Fatty Acids
- Fatty Acids, Unsaturated
- Female
- Gas Chromatography-Mass Spectrometry
- Humans
- Phospholipids
- Rats
- Serum Albumin
- Squalene
- Swine
- alpha-Fetoproteins
Alpha-1-6 fucosylated alpha-fetoprotein (AFP) is known to be elevated in patients with primary hepatoma and has been suggested as being useful as an early indicator and predictor of the poor prognosis for hepatoma. Although GDP-L-fucosyl-N-acetyl-beta-D-glucosaminide alpha-1-6 fucosyltransferase (alpha-1-6 FucT), is the key enzyme involved in alpha-1-6 fucosylation of AFP, when and how the expression of alpha-1-6 FucT is enhanced during hepatocarcinogenesis is unknown. Recently, we established a convenient assay method for this enzyme and were successful in the purification and cDNA cloning of alpha-1-6 FucT from human gastric cancer, as well as from porcine brain. In the present study, levels of alpha-1-6 FucT activity and mRNA expression have been determined during hepatocarcinogenesis in LEC rats which spontaneously develop hereditary hepatitis and hepatoma. The fetal liver contained the highest enzymatic activity, which tended to increase in inverse proportion to gestation. The enzymatic activity was significantly increased in hepatoma tissues as compared with uninvolved adjacent tissues. Northern-blot analysis revealed high expression of alpha-1-6 FucT mRNA in hepatoma tissues, whereas the expression was fairly low in normal, hepatitis and uninvolved adjacent liver tissues. While the fetal liver had the highest enzymatic activity, the expression of alpha-1-6 FucT mRNA was low, suggesting that another alpha-1-6 FucT is induced in fetal liver or that post-translational modification occurs. High expression of alpha-1-6 FucT was also observed in 3'-MeDAB-induced rat hepatomas and some rat hepatoma cell lines. Collectively, alpha-1-6 FucT was strongly enhanced from an early stage of hepatocarcinogenesis and was maintained at a high level in rat hepatomas.
MeSH Terms
- Aging
- Animals
- Carbohydrate Sequence
- Carcinogens
- Fucosyltransferases
- Gene Expression
- Liver
- Liver Neoplasms, Experimental
- Methyldimethylaminoazobenzene
- Molecular Sequence Data
- RNA, Messenger
- Rats
- Rats, Sprague-Dawley
To enroll a large percentage of the cancer high-risk group and to simultaneously screen for various kinds of cancer, a modified combination assay of tumor markers and risk factors in serum was devised. A pilot study using 5 tumor markers, AFP, CEA, CA19-9, CA125, Dupan-2, as well as 3 risk factors of pepsinogen, PGI, PGII, PGI/II, showed 87.0% sensitivity and 58.8% specificity in 54 patients with various cancers and 163 healthy subjects. Eighty percent of stage I or II cases were detected except for one stage I case of right lung cancer and one stage II case of oral cavity cancer. Field work is now under way to detect various cancers among approximately 1000 inhabitants above 50 years of age in a particular town using 11 tumor markers and 3 risk factors. One hundred fifty three of 967 cases (male 372, female 595) showed various abnormal values and some were examined further as higher risk cases to detect particular cancers suspected from the results of the modified combination assay. At present, 5 PAP positive cases were referred to urological clinic for examination and 3 were confirmed histologically as prostatic cancer. This corresponds to approximately a 0.8% of detection rate which is more than 40 times the prostatic cancer mortality. Other kinds of cancer are still under investigation at various specified clinics. If cancer is not detected in these higher risk cases, they will be followed year to year. Further, the most suspicious cases will be examined at a chromosome or DNA level.(ABSTRACT TRUNCATED AT 250 WORDS)
MeSH Terms
- Aged
- Aging
- Biomarkers, Tumor
- Female
- Humans
- Male
- Mass Screening
- Middle Aged
- Neoplasms
- Preventive Medicine
- Risk Factors
Knowledge of intracranial pressure may be important in many clinical situations in neonates and young infants. The best way to obtain this information would be a non-traumatic procedure. In order to test the reliability of a new fontanometer, the Rotterdam teletransducer, 25 simultaneous measurements of cerebrospinal fluid (CSF) pressure and anterior fontanelle pressure (AFP) were performed. Mean (SD) difference between CSF pressure and AFP was -0.2 (1.8) mm Hg (95% confidence interval from -0.48 to -0.88 mm Hg). The AFP was also measured in 60 healthy children (15 premature, 30 term newborn babies, and 15 infants). The different aspects of AFP were analysed and normal values computed. These results suggest that the Rotterdam teletransducer gives reliable continuous information about intracranial pressure and can be used in clinical practice. Interpretation of AFP plots must take the influence of postconceptional age and the physiological occurrence of pressure waves into account.
MeSH Terms
- Aging
- Brain Diseases
- Humans
- Infant
- Infant, Newborn
- Infant, Premature
- Intracranial Pressure
- Reproducibility of Results
- Transducers, Pressure
The estrogen binding characteristics of rat alpha-fetoprotein (AFP) and the testicular cytoplasmic estrogen receptor (E2R) and the ontogenic relationships between these two estrogen binding moieties were investigated. Sucrose gradient sedimentation analysis revealed that AFP migrated as a single 4.6S peak whereas the receptor migrated as a single peak in the 8-9S region. Scatchard analyses of the binding data demonstrated high-affinity (10(8) M-1), high-capacity (450 pmol/mg protein) binding sites for AFP-estradiol and high-affinity (10(10) M-1), low-capacity (16 fmol/mg protein) binding sites for receptor-estradiol. Estradiol binding in serum (AFP) was high at birth, declined during the first 2 weeks and fell to low levels during the fourth week of life. In contrast, the testicular E2R was not detectable before day 21, rose after day 23, and reached adult concentrations by day 35. The inverse pattern suggested a relationship between the disappearance of AFP and the appearance of the receptor. However, in vivo administration of Dexamethasone, which resulted in a precocious decrease in AFP levels, had no effect on the ontogeny of the receptor. The ontogenic patterns of these two estrogen binding moieties may determine the onset of testicular sensitivity to estrogens.
MeSH Terms
- Aging
- Amniotic Fluid
- Animals
- Animals, Newborn
- Centrifugation, Density Gradient
- Cytoplasm
- Estradiol
- Fetus
- Male
- Rats
- Rats, Inbred Strains
- Receptors, Estradiol
- Receptors, Estrogen
- Testis
- alpha-Fetoproteins
The ontogeny of expression of the alpha-fetoprotein (AFP) and albumin genes was examined in livers from late prenatal to 1-month-postpartum C3H/He mice. A parallel accumulation of both AFP and albumin mRNAs before birth, followed by a selective nonreciprocal decrease in AFP mRNA after birth, was observed. The decrease in AFP mRNA was the result of a decrease in transcription of the AFP gene, as measured by an in vitro nuclear transcription assay. We suggest a model for hepatic expression of the AFP and albumin gene cluster in which transcription of the two genes is activated simultaneously during differentiation and each gene is thereafter modulated independently in committed cells.
MeSH Terms
- Aging
- Animals
- Female
- Gestational Age
- Liver
- Mice
- Mice, Inbred C3H
- Nucleic Acid Hybridization
- Pregnancy
- RNA, Messenger
- Serum Albumin
- Transcription, Genetic
- alpha-Fetoproteins
Estrogen receptor-containing regions of limbic, hypothalamic and amygdaloid areas of the developing mouse brain exhibited little or no intraneuronal immunofluorescence reactivity for AFP in comparison with the bright fluorescence of adjacent regions. These regional differences in the topographic distribution of intraneuronal AFP may represent intrinsic differences in the uptake, turnover or immunoreactivity of the internalized protein, perhaps related to estrogen metabolism by such neurons.
MeSH Terms
- Aging
- Animals
- Brain
- Brain Chemistry
- Embryo, Mammalian
- Female
- Fluorescent Antibody Technique
- Male
- Mice
- Neurons
- Sex Factors
- Tissue Distribution
- alpha-Fetoproteins
The expression of the alpha-fetoprotein (AFP) gene was studied in rat liver and kidney. A significant level of AFP mRNA was found in neonatal liver and kidney, but not in adult tissues. Unlike liver the re-expression of AFP mRNA was not seen upon chemically induced regeneration of the kidney. Treatment of neonatal rats with dexamethasone caused a decrease in liver AFP mRNA levels, but a similar decrease was not apparent in kidney. Northern analysis revealed AFP mRNA size to be identical in neonatal liver and kidney. The results suggest different gene regulatory mechanisms in liver and kidney for the AFP gene.
MeSH Terms
- Aging
- Animals
- Animals, Newborn
- Dexamethasone
- Gene Expression Regulation
- Kidney
- Liver
- Nucleic Acid Hybridization
- RNA, Messenger
- Rats
- Rats, Inbred Strains
- Regeneration
- alpha-Fetoproteins
To determine whether methylation changes in specific DNA sequences of the albumin and AFP genes are implicated in the modulation of transcriptional activity during rat liver development and neoplasia we have analysed the methylation pattern of C-C-G-G sequences within these genes in DNA isolated from fetal and adult hepatocytes, from adult kidney and from a clonal hepatoma cell line which produces AFP but no albumin. We have assayed for methylation of the internal cytosine of this sequence by using the restriction enzyme isoschizomers HpaII and MspI. 32P-labelled cloned cDNA probes were used to reveal the albumin and AFP gene containing fragments. Genomic subclones of the albumin gene were also utilized as molecular probes to measure quantitatively the level of methylation of 6 specific sites within the albumin gene in the different DNA samples. The results indicate that methylation changes at the sites analysed are not responsible for the changes in gene activity during rat liver development. Further they demonstrate that: 1) extensively methylated genes can be actively transcribed; 2) prominent changes in methylation of specific genes during normal development are not necessarily related to alterations in gene activity.
MeSH Terms
- Aging
- Animals
- Cell Line
- DNA
- DNA Restriction Enzymes
- Female
- Genes
- Kidney
- Liver
- Liver Neoplasms, Experimental
- Methylation
- Pregnancy
- Rats
- Rats, Inbred BUF
- Rats, Inbred Strains
- Serum Albumin
- alpha-Fetoproteins
The immunocytochemical localization of the alpha-fetoprotein (AFP), serum albumin (ALB), transferrin (Tf) and immunoglobulins (IgG) in developing rat brain has been studied by the indirect peroxidase technique using rabbit antibodies to AFP, ALB, Tf and IgG followed by goat anti-rabbit immunoglobulins conjugated with peroxidase. Evidence of a high selective staining for AFP and ALB is presented. The pattern of morphological localization of both proteins was similar throughout fetal and post-natal development up to 20-25 days of age. Large areas and groups of cells in all regions of the brain from the olfactory bulb to the medulla oblongata appeared positively stained at a given moment in the development. The labeling was cytoplasmic and, in the neuronal elements, extended to their axonic and dentritic prolongations. The intracellular localization of AFP and ALB in the developing rat brain may be related to the binding affinity of these proteins for oestrogens and/or essential fatty acids. The morphological data presented here suggest that both proteins are actively involved in the uptake of such substances by the cellular structures of the brain.
MeSH Terms
- Aging
- Animals
- Animals, Newborn
- Brain
- Brain Chemistry
- Immunoenzyme Techniques
- Immunoglobulin G
- Rats
- Rats, Inbred Strains
- Serum Albumin
- Transferrin
- alpha-Fetoproteins
In an attempt to study the diagnostic value of alpha-fetoprotein (AFP), serum AFP concentrations were measured by radioimmunoassay in 34 neonates and infants with obstructive hepatobiliary diseases and the results were compared with the normal ranges of AFP at this age. Eighteen of 24 infants with biliary atresia and four of six infants with neonatal hepatitis had raised AFP values. In only one of four infants with choledochal cyst, did the AFP value exceed the normal range. In 10 older children with this lesion, AFP was normal. Serum AFP concentrations in biliary atresia did not correlate with the serum bilirubin, s-GOT, s-GPT, anatomic type of the lesion or postoperative bile flow. From these observations, it would appear that the elevation of AFP in infantile cholestasis is unrelated to underlying diseases except in case of alpha 1-antitrypsin deficiency. Serum AFP concentrations in neonates with physiological jaundice, were seldom elevated, and showed a good correlation with serum levels of total bilirubin. Possible mechanisms causing this elevation of AFP may be different from those involved in infantile cholestasis.
MeSH Terms
- Aging
- Cholestasis
- Cholestasis, Intrahepatic
- Common Bile Duct Diseases
- Cysts
- Humans
- Infant
- Infant, Newborn
- Jaundice, Neonatal
- Reference Values
- alpha-Fetoproteins
Rat alpha 1-fetoprotein (AFP) and albumin mRNA levels have been examined in yolk sac and liver during late gestation and early neonatal life by cell-free translation and RNA-excess cDNA hybridization. AFP-specific sequences were found to comprise up to 25% of the total poly(A)-containing RNA in the yolk sac, and they were reduced about 10-fold in the fetal liver. Since comparable amounts of poly(A)-containing RNA were obtained from both tissues, these observations suggest that the yolk sac may be the major source of maternal and fetal plasma AFP in late gestation. The level of AFP mRNA sequences in fetal liver remained relatively constant during the last week of gestation and the first 2 weeks of neonatal life. In contrast, the concentration of albumin sequences increased steadily during this time, reaching about 85% of adult levels by 2 weeks of age. These results suggest that the expression of AFP and albumin genes may not be reciprocally regulated, but rather they may be regulated independently of each other during the perinatal period. Albumin-specific sequences were also detected in the poly(A)-containing RNA from yolk sac but at a level of more than 400-fold lower concentration than that of the fetal liver. It was especially noteworthy that the relative level of AFP sequences in the yolk sac decreased much earlier than that in the liver. Thus, AFP gene expression may be subject to different developmental controls in these two tissues. The continuation of AFP production in the liver following birth may indicate a continuing functional requirement for this protein in early neonatal life.
MeSH Terms
- Aging
- Animals
- Female
- Fetus
- Liver
- Nucleic Acid Hybridization
- Pregnancy
- Protein Biosynthesis
- RNA, Messenger
- Rats
- Serum Albumin
- Yolk Sac
- alpha-Fetoproteins
We report the cellular localization of alpha-fetoprotein (AFP) and albumin (ALB) gene transcripts in rat kidney and brain as detected by in situ hybridization on tissue sections with [35S]-labelled alpha-fetoprotein and albumin cDNA probes. Both types of mRNA were present in distinct cell populations of the developing kidney and brain. In the kidney, both gene transcripts were distributed over all developing tubular cells in the 20-day-old fetus. During the first 3 weeks of life, a gradual decrease in the expression of AFP and ALB mRNA was apparent, the rate of decrease being greater on proximal tubules than on the other tubular cells. From the 4th week onwards, a weak signal for both mRNAs persisted in the majority of the tubular cells. In the brain, all neuronal cells expressed both genes. Transcript cellular distribution was mainly cytoplasmic during fetal and early postnatal life and became predominantly nuclear at 3, 4 and 5 weeks, suggesting that posttranscriptional mechanisms are involved in the control of AFP and ALB gene expression at these stages. In the adult brain no significant signal was recorded thereafter. Coexpression of AFP and ALB transcripts by specific cell types, together with their gradual disappearance concomitant with postnatal organ maturation, suggests a possible role for these proteins in terminal differentiation processes of tubular and neuronal cells.
MeSH Terms
- Aging
- Albumins
- Animals
- Brain
- Embryonic and Fetal Development
- Gene Expression Regulation
- Kidney
- Nucleic Acid Hybridization
- RNA, Messenger
- Rats
- alpha-Fetoproteins
The mammalian liver undergoes a number of dramatic changes in gene expression during development. One of these is typified by the alpha-fetoprotein (AFP) gene, which is activated in the fetal liver but undergoes a transcriptional decline at birth. In contrast, although activated at the same time during fetal development, albumin gene transcription is maintained at high levels in adult animals. To determine whether the postnatal decline in AFP gene transcription is mediated through its distal enhancers or through more proximal elements surrounding the promoter or structural gene, chimeric genes bearing substitutions of albumin gene cis-acting elements for the equivalent AFP gene elements were introduced into the germ line of mice. The expression of the transgenes was then analyzed at various stages of development. Our results indicate that the AFP gene enhancers are not involved in the postnatal decline in AFP transcription. Rather, a region within the first kilobase of DNA upstream of the AFP gene, including its promoter, and/or portions of the structural gene is sufficient to direct postnatal repression of the gene.
MeSH Terms
- Aging
- Albumins
- Animals
- Chimera
- Enhancer Elements, Genetic
- Gene Expression Regulation
- Mice
- Mice, Transgenic
- Microinjections
- Organ Specificity
- RNA
- Repressor Proteins
- Transcription Factors
- Transcription, Genetic
- Zygote
- alpha-Fetoproteins
We have studied the evolution of the incorporation of alpha-fetoprotein (AFP) and albumin by mouse tissues from fetal to adult life. Mice were injected with 125I-labelled AFP or albumin and, 3 h later, blood and organs were removed and analyzed for their radioactive protein content. Results showed that all immature tissues examined took up both AFP and albumin from blood. AFP uptake was higher during fetal and early postnatal life and decreased with age. In general, the relative uptake of albumin was lower than that of AFP, and the time-course incorporation of both proteins was parallel in brain, liver and kidney. In other tissues such as white adipose tissue, brown adipose tissue and skin. AFP uptake decreased while albumin uptake remained almost constant or increased with age. In the fetal period, the strong AFP uptake in white adipose tissue contrasted with the much lower albumin incorporation by this tissue. Autoradiographs from sections of organs and entire animals confirmed the cytoplasmic localization of AFP and albumin. We conclude that AFP and albumin found in developing tissues, except for fetal liver and yolk sac, proceed mostly from blood uptake. These results agree with recent experimental data suggesting that the major physiological role of AFP is the transport and delivery of polyunsaturated fatty acids to developing tissues.
MeSH Terms
- Adipose Tissue
- Aging
- Animals
- Animals, Newborn
- Brain
- Fetus
- Kidney
- Liver
- Mice
- Serum Albumin
- Skin
- alpha-Fetoproteins
By use of different restriction enzymes sensitive to internal cytosine methylation (HpaII, AvaI, HhaI) we have analysed the methylation patterns of albumin and AFP genes in tissues and cell lines with high (liver, yolk sac, hepatoma cell lines), low (fetal and neonatal kidney) or undetectable (spleen, JF1 fibroblasts) expression of either gene. We show that expression of the AFP gene is associated to the demethylation of a whole region or domain extending from -4 to 3 Kb. Moreover, demethylation of a site located at the upstream limit of this domain appears to be correlated with the commitment of the cell type to synthesize AFP. As concerns the albumin gene, we show that the domain in which demethylation is correlated with active gene transcription in hepatoma cell lines has different borders than in tissue. This difference might be related to the different amounts of mRNA synthesized or to an alteration in gene regulation in tumor cells. Finally, we show that low expression of albumin and AFP genes in fetal and neonatal kidney is not correlated with domain demethylation, suggesting that the regulatory mechanisms of expression of these genes are different in kidney as compared with liver.
MeSH Terms
- Aging
- Albumins
- Animals
- Animals, Newborn
- Base Sequence
- Cell Line
- DNA (Cytosine-5-)-Methyltransferases
- Embryonic and Fetal Development
- Gene Expression Regulation
- Liver
- Liver Neoplasms, Experimental
- Male
- Rats
- Rats, Inbred Strains
- Tissue Distribution
- alpha-Fetoproteins
Three major regions of DNase I hypersensitivity (DH) were found in alpha 1-fetoprotein (AFP) chromatin of rat liver. DH site I is located at the transcription initiation site and associated with ongoing AFP transcription. DH site II is located 2.5 kb upstream from the cap site: it is developmental stage-dependent but dissociable from ongoing AFP transcription. DH site III, 3.7 kb upstream from the cap site, behaves as hepatocyte-constitutive. DH sites are present in similar regions of liver albumin chromatin. Dexamethasone-induced AFP gene repression is accompanied by the selective loss of AFP DH site I, a likely result of glucocorticoid receptors binding to a DNA recognition sequence located 5'-adjacent to DH site I. Sl nuclease-hypersensitive sites were found on naked superhelical AFP and albumin DNA, but do not appear to contribute DH sites in liver chromatin. The extent of hypomethylation of HpaII sites at the 5'-end of the AFP gene correlates positively with the level of potential and actual expression of the gene. We conclude that developmental and hormonal regulation of the AFP gene is confined within congruent to 4 kb of 5'-flanking DNA, and we discuss possible hierarchical interactions among DH sites, in relation to DNA methylation and replication.
MeSH Terms
- Aging
- Animals
- Brain
- Cloning, Molecular
- DNA Restriction Enzymes
- Deoxyribonuclease I
- Dexamethasone
- Genes
- Liver
- Liver Neoplasms, Experimental
- Liver Regeneration
- Male
- Methylation
- Nucleotide Mapping
- Rats
- Rats, Inbred Strains
- Transcription, Genetic
- alpha-Fetoproteins
Estrogens are teratogens and developmental carcinogens in several species. We have used uterine growth to quantitate the potency of three estrogens [estradiol (E2), diethylstilbestrol (DES), ethynylestradiol (EE2)] during four postnatal periods (days 1-5, 10-14, 20-24, and 60-64) in the rat. Alphafetoprotein (AFP), present at high levels in neonatal serum, is thought to regulate estrogen bioavailability. Association constants for DES and EE2 were 2.7% and 4.9% of that for E2 binding to AFP, determined in a batch Sephadex equilibrium binding assay. On days 1-5, DES and EE2 were about 80-fold more potent than E2 in increasing uterine weight. As AFP levels fell, potency differences between E2 and the synthetic estrogens decreased. In the adult, which essentially lacks AFP, the three estrogens were nearly equipotent. These data are consistent with AFP regulation of estrogen potency. On days 10-14, uterine growth was less sensitive than at other ages to all three estrogens, perhaps related to uterine differentiation and/or the high endogenous serum E2 levels reported at this age. However, when we examined another uterine estrogen response, ornithine decarboxylase (ODC) induction at 6 h following estrogen injection, all three hormones were about equipotent in both neonatal and adult animals. This apparently AFP-independent event shows dissociation of ODC induction and uterine growth, which could be due to separate mechanisms for hormone entry to target tissue or subsequent intracellular events.
MeSH Terms
- Aging
- Animals
- Diethylstilbestrol
- Estradiol
- Estrogens
- Ethinyl Estradiol
- Female
- Kinetics
- Organ Size
- Ornithine Decarboxylase
- Pregnancy
- Protein Binding
- Rats
- Uterus
- alpha-Fetoproteins
We have studied the effect of thyroid disfunction during the postnatal period, on the serum and brain levels of rat alpha-fetoprotein (AFP) and albumin. Hypothyroidism was induced by treatment of pregnant rats and their newborn pups with 2-mercapto-1-methylimidazole(methimazole). Hyperthyroidism was provoked in newborns by daily injections of thyroxine (0.25 micrograms/g body wt) from the 3rd postnatal day weaning. Impaired growth, lower brain size, altered behaviour and morphological features observed were according to an altered thyroid status. Hypothyroid rats showed a significantly reduction in serum AFP concentration (78% of control values at 8 days of age) and a slight increase in that of albumin. level could be appreciated. Thyroxine supplementation (0.2 micrograms/rat/day) corrected most of these alterations. Hyperthyroidism induced a drastic fall in both serum and brain AFP levels (about 48% of the corresponding control values). Albumin concentration in serum was augmented significantly from the 12th postnatal day, but its brain levels did not change significantly. In hyperthyroid rats, a significant reduction (37% relative to controls) in the concanavalin A-non reactive microform of AFP, was observed. This alteration of the glycosylation pattern of AFP could be due to the inhibition by thyroxine of the activity of the hepatic enzyme GlcNAc-transferase III.
MeSH Terms
- Aging
- Animals
- Animals, Newborn
- Body Weight
- Brain
- Concanavalin A
- Glycosides
- Hyperthyroidism
- Hypothyroidism
- Immunoelectrophoresis, Two-Dimensional
- Rats
- Rats, Inbred Strains
- Serum Albumin
- Thyroxine
- alpha-Fetoproteins
Steroid hormones, which affect development of reproductive traits, alter immune responses in rodents and appear to control severity of disease in F1 hybrid NZB/W mice, an animal model of systemic lupus erythematosus. We tested the hypothesis that exposure of NZB/W fetuses to altered hormonal environments would influence subsequent expression of autoimmune renal disease and affect longevity. NZB females, pregnant with NZB/W fetuses, were treated from Days 13-18 of gestation with testosterone or the antiandrogen, flutamide. Similar treatments were carried out in C57BL/6 dams mated to DBA/2 males to permit comparison with nonautoimmune hybrid mice. Serum concentrations of testosterone were greater in testosterone-implanted dams of both strains, but concentrations of estradiol were greater only in C57BL/6 dams treated with flutamide. Alpha fetoprotein (AFP), which binds estrogen and modulates immune responsiveness, was greater in serum from both groups of testosterone-treated dams, while flutamide treatment increased serum AFP only in NZB dams. We conclude that factors governing circulating estradiol and AFP differed in pregnant NZB and C57BL/6 females. Morphological analyses confirmed effects of hormonal manipulation on the developing fetuses. Testosterone implants resulted in female offspring with greater anogenital spaces, and treatment of dams with flutamide eliminated the expected difference between anogenital spaces in females and males. Effects of altered prenatal hormonal environments on immune-mediated disease in NZB/W offspring were examined in a longevity study. Early deaths were delayed in NZB/W females produced by flutamide-treated dams. An unexpected result was observed in NZB/W males. Male offspring from both testosterone- and flutamide-treated mothers lived longer than males from control dams. This paradox suggested that a characteristic shared by both groups of treated NZB dams had similar effects on the developing fetuses. It is proposed that elevated concentrations of AFP modulated the course of autoimmune disease and contributed to increased longevity in NZB/W offspring of treated dams.
MeSH Terms
- Animals
- Autoimmune Diseases
- Female
- Fetus
- Flutamide
- Hormones
- Longevity
- Male
- Maternal-Fetal Exchange
- Mice
- Mice, Inbred NZB
- Ovary
- Pregnancy
- Reproduction
- Seminal Vesicles
- Testosterone
To examine the relationship between blood levels of 16 alpha-[18F]fluoro-17 beta-estradiol(18F-ES) and serum alphafetoprotein (AFP) concentration, we undertook a study in which serum from various aged (20-33 days old) Sprague-Dawley female rats injected with 18F-ES was analyzed for both blood activity levels and AFP. There is a strong positive correlation between serum AFP concentration and 18F-ES blood levels (r = 0.914, P less than 0.001), suggesting that the binding of 18F-ES by AFP has a significant effect on blood activity levels. The AFP concentration and ultimately the AFP-18F-ES binding is dependent on the age and weight of the rat: younger, as well as low weight rats exhibited high AFP concentrations and consequently increased 18F-ES blood activity. The rats most suitable for comparative studying of labeled estrogens are 25-28 days of age and weigh a minimum of 50-55 g. Thus, the use of the immature rat model to compare labeled estrogens requires a careful consideration of possible interference from blood binding proteins (i.e. AFP), as well as potential receptor binding competition from endogenous estrogens produced during the estrous cycle. Comparable consideration of blood binding proteins (sex steroid binding protein, SBP) and endogenous estrogens must be made in human studies, as well.
MeSH Terms
- Aging
- Animals
- Body Weight
- Estradiol
- Female
- Protein Binding
- Rats
- Rats, Inbred Strains
- alpha-Fetoproteins
DNase I footprinting assays were performed to identify the binding sites for putative trans-acting factors involved in the control of alpha-fetoprotein (AFP) gene expression using mouse AFP promoter fragments (-839 to 56) and nuclear protein extracts from fetal, newborn, and adult livers and from brain and kidney. Our studies have shown that with nuclear protein from adult mouse liver, there are 14 protected regions in the AFP promoter up to -839 base pairs (bp). Region I (-82 to -43) was protected by at least three different factors, one of which is CCAAT-binding/enhancer-binding protein. This region is highly conserved in the mouse, rat, and human AFP genes and has been shown previously to be essential for the regulation of tissue-specific expression in mouse. Differences in DNase I protection with fetal, newborn, and adult nuclear proteins have been observed in the proximal promoter region (up to -202 bp) and in regions further upstream (up to -839 bp). Significant differences among liver, kidney, and brain nuclear protein-binding sites have also been observed. In these studies, we have mapped the fetal and adult nuclear protein-binding sites of the cis-acting DNA sequences of the mouse AFP proximal promoter (up to -200) and have identified specific protein-binding sites in the distal promoter (-200 to -839). We have also identified the sites of the AFP promoter which bind nuclear proteins from highly differentiated tissues in which AFP is not expressed.
MeSH Terms
- Aging
- Animals
- Base Sequence
- Brain
- Cell Nucleus
- DNA
- DNA-Binding Proteins
- Deoxyribonuclease I
- Fetus
- Genes
- Kidney
- Liver
- Mice
- Mice, Inbred C3H
- Molecular Sequence Data
- Nuclear Proteins
- Nucleotide Mapping
- Organ Specificity
- Promoter Regions, Genetic
- Restriction Mapping
- alpha-Fetoproteins
Persistent infection of the eastern woodchuck (Marmota monax) with the woodchuck hepatitis virus (WHV) produces disease sequelae similar to those observed in humans with persistent hepatitis B virus infection, including hepatocellular carcinoma (HCC). To further characterize serological markers of HCC in the woodchuck, serum alpha-fetoprotein (AFP) was measured under normal physiological conditions and following infection with WHV. Serum AFP was elevated in association with WHV-induced hepatitis and HCC and was a useful indicator of hepatic responses in individual animals throughout the course of experimental WHV infection. The frequent occurrence of normal elevations in serum AFP during the fall and winter, however, limits the use of AFP as a marker for early detection of HCC. The present temporal studies of AFP responses in WHV-infected woodchucks have identified several stages of infection where virological and cellular interactions can be investigated at the molecular level. Studies of AFP in the woodchuck model should provide opportunities to further elucidate the physiological and immunological functions of AFP and to understand virus-host cell interactions during the course of experimental hepadnavirus infection leading to HCC.
MeSH Terms
- Aging
- Animals
- Biomarkers
- Disease Models, Animal
- Female
- Hepadnaviridae
- Hepatitis, Viral, Animal
- Liver Neoplasms, Experimental
- Male
- Marmota
- Pregnancy
- Radioimmunoassay
- Reference Values
- Seasons
- alpha-Fetoproteins
The ontogeny of alpha-fetoprotein (AFP) gene expression has been examined in the fetal and adult mouse gastrointestinal tract. AFP mRNA constitutes approximately 0.1% of total mRNA in the fetal gut. The transcripts were localized by in situ hybridization to the epithelial cells lining the villi of the fetal gut. At birth, AFP mRNA declines rapidly to achieve low adult basal levels, which are not affected by different alleles of raf, a gene that determines the adult basal level of AFP mRNA in the liver. The basal level in the adult gut is the consequence of continued AFP transcription in a small number of enteroendocrine cells that are distributed infrequently on the villi. These cells were identified by double antibody staining with antibodies to chromogranin A, an enteroendocrine cell marker and AFP. Previous studies resulted in the generation of a line of transgenic mice containing an internally deleted AFP gene that was greatly overexpressed in the fetal gut. The basis for the inappropriately high level expression of the transgene was shown to be the consequence of very high levels of transcription in the epithelial cells of the villi rather than to expression in inappropriate cell types. The cis-acting DNA sequences required for expression of the AFP gene in the gut were investigated using Caco-2 cells, a human colon adenocarcinoma cell line. These experiments indicated that, with one exception, the regulatory elements required in both the promoter and enhancer regions of the gene coincided with those that are necessary for high level expression in the liver. The one exception was enhancer II, located 5 kbp of DNA upstream of the gene, which exhibited no activity in Caco-2 cells.
MeSH Terms
- Aging
- Animals
- Cell Line
- Chromogranin A
- Chromogranins
- Cloning, Molecular
- DNA Probes
- Digestive System
- Embryonic and Fetal Development
- Enhancer Elements, Genetic
- Exons
- Fetus
- Gene Expression
- Humans
- Immunohistochemistry
- Mice
- Mice, Inbred ICR
- Mice, Transgenic
- Nucleic Acid Hybridization
- RNA Probes
- RNA, Messenger
- Transcription, Genetic
- Transfection
- alpha-Fetoproteins
The morphological localisation of alphafetoprotein (AFP), serumalbumin (SA), transferrin and immunoglobulins (IgG) has been studied in the developing central nervous system of the Rat by immunocytochemical methods. Evidence is presented of a highly selective staining for AFP and SA, both proteins exhibiting the same topographical distribution. Practically all the areas of the brain and the spinal cord are stained at a given moment of the developmental process. The labeling is cytoplasmic and in the neuronal elements extends to their axonic and dendritic prolongations. The localization of AFP and SA in the nervous system may be related to the well known binding properties of these proteins for varied substances (estrogen and/or fatty acids). The morphological data presented here suggest that both proteins may be actively involved in the uptake of such substances by the cellular structures of the nervous tissue.
MeSH Terms
- Aging
- Animals
- Brain
- Fetus
- Histocytochemistry
- Immunoglobulin G
- Rats
- Serum Albumin
- Spinal Cord
- Transferrin
- alpha-Fetoproteins
Quantitative data are presented on the fatty acid composition of rat alpha-fetoprotein (AFP) and serum albumin, (SA), and of brain extracts of suckling rats. In AFP and SA preparations, 40% and 13%, respectively, of total fatty acids present are polyenoic acids. Among them, docosahexaenoic acid is quantitatively the most important in AFP, while in SA, arachidonic acid is largely predominant. Both docosahexaenoic and arachidonic acids were the predominant polyenoic acids in brain extracts. The rate of accumulation of these acids in the brain of suckling rats and the rate of AFP secretion during the same period showed a maximum around 10--12 days after birth. These results suggest that AFP and SA play an important role in the transport and the incorporation of polyunsaturated fatty acids in the developing brain.
MeSH Terms
- Aging
- Animals
- Animals, Newborn
- Brain
- Fatty Acids
- Humans
- Protein Binding
- Rats
- Serum Albumin
- Structure-Activity Relationship
- alpha-Fetoproteins