AQP3
Aquaporin-3 (AQP-3) (Aquaglyceroporin-3)
Publications[править]
The ability to control facial skin physiology and appearance through the oral mucosa (transbuccally) is largely unexplored. Here, a hypothesis was tested that transbuccal delivery of fat tissue-supportive actives may trigger beneficial cosmetic responses at the level of the skin. First, the importance of the fat tissue for skin structure and function was established by comparative analysis of human biopsies cultured defatted or in the presence of hypodermis, using macroscopic observation, quantitative polymerase chain reaction, and histochemistry. Then, the ability to improve epidermal function and structure through the application of a lipoactive patch to oral mucosa was demonstrated in a clinical case study by the quantification of several epidermal microRNAs (miRNAs). It was found that removal of the hypodermal fat layer accelerated skin biopsy aging as demonstrated by the deterioration of the physical appearance at the macroscopic and microscopic (hematoxylin and eosin stain) levels and the decrease of expression of genes implicated in the structure and function of the skin, such as AQP3 and LOR. Furthermore, when adipogenic actives were applied to the oral mucosa under a form of bioadhesive film in a clinical case study, an improvement in the expression of miRNA biomarkers of senescence and inflammation was observed in the epidermis. Taken together, these results indicate that the transbuccal delivery of lipogenic compounds to face is a novel method for the improvement of facial skin structure and function.
Keywords
- adipocytes
- aging
- cosmetics
- face
- fat pads
- integument
- subcutis
- wrinkles
Senescence-associated alterations in structure and function of cornea make it more sensitive to traumas and disease. Trauma of cornea leads to edema and vision impairment and only corneal transplantation remains the effective for vision correction. Role of aquaporins for cornea endothelium function, as well as age-related changes of their activity, are not entirely understood. Herein, we studied changes with age the water permeability (Pf) of the plasma membranes of the corneal endothelial cells and the level of expression in them of the mRNA genes of the water channels of the aquaporins AQP1 and AQP3 in Wistar and senescence-accelerated OXYS rats. From the age of 3 to 18 months, Pf in Wistar rats increased, in OXYS - decreased and was twice lower than in Wistar rats. The expression of aqp1 mRNA (studied by RT-PCR) in the endothelium was the same in Wistar and OXYS rats at the age of 3 months. By the age of 18 months, it increased only in Wistar rats and became twice higher than in OXYS rats. The expression of aqp3 mRNA in the endothelium of 3-month-old OXYS rats was half that of Wistar rats and did not change with age, while in Wistar rats it decreased and at 18 months was 4 times lower than in 3 months. We supposed that increased water permeability of endothelial cells in Wistar rats is adaptive and compensates for the decrease in endothelial cell density with age, while the accelerated aging of OXYS rats abolishes this compensation.
MeSH Terms
- Age Factors
- Aging
- Animals
- Aquaporin 1
- Aquaporin 3
- Disease Models, Animal
- Endothelial Cells
- Epithelium, Corneal
- RNA, Messenger
- Rats
- Rats, Wistar
Keywords
- aging
- cornea endothelium
- senescence-accelerated OXYS rats
- water permeability
Previously we demonstrated that neonatally induced partial unilateral ureteral obstruction (PUUO) in rats is associated with changes in the abundance of renal acid-base transporters that were paralleled by reduction in renal functions dependent on the severity and duration of obstruction. The aim of the present study was to identify whether changes in renal aquaporin abundance are age-dependent. Semiquantitative immunoblotting and immunohistochemistry were used to examine the changes in abundance of AQP1, AQP2, p-S256AQP2 (AQP2 phosphorylated at consensus site Ser(256)) and AQP3 in the kidneys of rats with neonatally induced PUUO within the first 48 h of life, and then monitored for 7 or 14 weeks. Protein abundance of AQP2 and AQP3 increased in both obstructed and non-obstructed kidneys 7 weeks after induction of neonatal PUUO (PUUO-7W). In contrast, AQP1 and AQP2 protein abundance in the obstructed kidney were reduced after 14 weeks of PUUO (PUUO-14W). Importantly, pS256-AQP2 protein abundance was reduced in obstructed kidneys of both PUUO-7W and PUUO-14W. Immunohistochemistry confirmed the persistent pS256-AQP2 downregulation in both PUUO-7W and PUUO-14W rats. The study shows that the protein abundance of AQP1, AQP2, and AQP3 in the obstructed kidney is increased in PUUO-7W, which may be a compensatory phenomenon and reduced in PUUO-14W rats suggesting a time-/age-dependent dysregulation in response to PUUO. pS256-AQP2 protein abundance is reduced consistent with obstruction-induced direct effects in the apical part of the collecting duct principal cells in response to PUUO.
MeSH Terms
- Age Factors
- Aging
- Animals
- Animals, Newborn
- Aquaporin 1
- Aquaporin 2
- Aquaporin 3
- Aquaporins
- Blotting, Western
- Disease Models, Animal
- Hydronephrosis
- Immunohistochemistry
- Kidney
- Male
- Phosphorylation
- Rats
- Ureteral Obstruction
Salivary glands are involved in secretion of saliva, which is known to participate in the protection and hydratation of mucosal structures within the oral cavity, oropharynx and oesophagus, the initiation of digestion, some antimicrobial defence, and the protection from chemical and mechanical stress. Saliva secretion is a watery fluid containing electrolytes and a mixture of proteins and can be stimulated by muscarinic and adrenergic agonists. Since water movement is involved in saliva secretion, the expression, localization and function of aquaporins (AQPs) have been studied in salivary glands. This review will focus on the expression, localization and functional roles of the AQPs identified in salivary glands. The presence of AQP1, AQP5 and AQP8 has been generally accepted by many, while the presence of AQP3, AQP4, AQP6 and AQP7 still remains controversial. Functionally, AQP5 seems to be the only AQP thus far to be clearly playing a major role in the salivary secretion process. Modifications in AQPs expression and/or distribution have been reported in xerostomic conditions.
MeSH Terms
- Aging
- Animals
- Aquaporin 5
- Aquaporins
- Biological Transport, Active
- Cell Line
- Diabetes Mellitus
- Head and Neck Neoplasms
- Humans
- Protein Transport
- Salivary Glands
- Sjogren's Syndrome
- Water
- Xerostomia
Kidneys of new-born animals are resistant to arginine vasopressin (AVP). The ability of the hormone to regulate water permeability of the collecting duct can be seen from weaning period, probably due to the maturation of the intracellular signaling pathway. The purpose of the present work was to investigate the effect of V2 receptor agonist dDAVP on the water permeability of OMCD basolateral membrane in 10-, 22- and 60-day old Wistar rats. We also estimated ontogenetic gene expression of AQP2, AQP3, AQP4 and V2 receptor. Osmotic water permeability (Pf) of the basolateral membrane of microdissected OMCD was measured under control conditions and after incubation with the agonist V2 receptor desmopressin (dDAVP; 10(-7) M). Water permeability in 10- and 22-day old rats under control conditions were significantly higher than in adults. Desmopressin stimulated significant increase of this parameter in 22-day old pups (Pf = = 125 /- 4.85; Pf = 174 /- 8.2 microns/s, p < 0.001) and adult rats (Pf = 100.5 /- 7.38; Pf = 178.8 /- 9.54 microns/s, p < 0.001). Osmotic water permeability of the OMCD basolateral membrane in 10-day old rats does not depend on dDAVP (Pf = 172.5 /- 23.8; Pf = 164.8 /- 34 microns/s). With the RT-PCR, we observed a gradual increase of AQP2 and V2 receptor genes expression during postnatal ontogenesis. The gene expression of AQP3 and AQP4 remained unchanged during postnatal ontogenesis. In general, the water permeability of the OMCD basolateral membrane of rats can be stimulated by AVP since the 22nd day of postnatal life. The water permeability of the OMCD basolateral membrane under control conditions gradually decreased during postnatal development, while gene expression of AQP3 and AQP4 was unchanged. The mechanism of this decrease remains to be established.
MeSH Terms
- Aging
- Animals
- Aquaporin 2
- Aquaporin 6
- Aquaporins
- Cell Membrane Permeability
- Deamino Arginine Vasopressin
- Female
- Kidney Medulla
- Kidney Tubules, Collecting
- Male
- Osmosis
- Rats
- Rats, Wistar
- Receptors, Vasopressin
- Renal Agents
- Water
The expression and localization of aquaporins (AQP1-AQP5), members of the water channel family, in the developing rat submandibular gland were analysed using RT-PCR, Northern blotting and immunohistochemistry to explore their relation to the development of this salivary gland. RT-PCR analysis revealed unique expression patterns of each AQP. AQP1 was expressed constitutively during prenatal development, whereas the expression of AQP5 became more intense in the course of development from embryonic day 16.5 (E16) to E20. These expression patterns concurred with the results of Northern blot analysis. AQP3 and AQP4 mRNAs in the prenatal development were not detected in Northern blots, although they were detected by RT-PCR. During postnatal development, AQP5 and AQP1 mRNAs were expressed continuously, but no message for AQP3 or AQP4 was detected. AQP2 mRNA was not detected during either prenatal or postnatal development in this tissue. Immunohistochemical studies revealed that AQP5 was first localized at the apical membrane of proacinar cells at E18, and then became clearly distributed at the apical membrane of acinar cells in accordance with the differentiation and establishment of the mature acini. In addition, some vasculature also showed immunoreactivity for AQP5. AQP1 was immunolocalized in the blood vessels, including capillaries, of the gland throughout development. These observations suggest the existence of transcriptional regulation of rat AQP5, which is one of the most probable regulators of saliva production and secretion, during the establishment of the functional submandibular salivary gland.
MeSH Terms
- Aging
- Amino Acid Sequence
- Animals
- Aquaporins
- Biological Transport, Active
- Blotting, Northern
- Body Water
- Female
- Immunohistochemistry
- Molecular Sequence Data
- Pregnancy
- RNA
- RNA, Antisense
- Rats
- Rats, Sprague-Dawley
- Reverse Transcriptase Polymerase Chain Reaction
- Sodium-Potassium-Exchanging ATPase
- Submandibular Gland
Senescent female WAG/Rij rats exhibit polyuria without obvious renal disease or defects in vasopressin plasma level or V(2) receptor mRNA expression. Normalization of urine flow rate by 1-desamino-8-d-arginine vasopressin (dDAVP) was investigated in these animals. Long-term dDAVP infusion into 30-mo-old rats reduced urine flow rate and increased urine osmolality to levels comparable to those in control 10-mo-old rats. The maximal urine osmolality in aging rat kidney was, however, lower than that in adult kidney, despite supramaximal administration of dDAVP. This improvement involved increased inner medullary osmolality and urea sequestration. This may result from upregulation of UT-A1, the vasopressin-regulated urea transporter, in initial inner medullary collecting duct (IMCD), but not in terminal IMCD, where UT-A1 remained low. Expression of UT-A2, which contributes to medullary urea recycling, was greatly increased. Regulation of IMCD aquaporin (AQP)-2 (AQP2) expression by dDAVP differed between adult and senescent rats: the low AQP2 abundance in senescent rats was normalized by dDAVP infusion, which also improved targeting of the channel; in adult rats, AQP2 expression was unaltered, suggesting that IMCD AQP2 expression is not regulated by dDAVP directly. Increased AQP3 expression in senescent rats may also be involved in improved urine-concentrating capacity owing to higher basolateral water and urea reabsorption capacity.
MeSH Terms
- Aging
- Animals
- Aquaporin 2
- Aquaporin 3
- Aquaporin 6
- Aquaporins
- Carrier Proteins
- Corticosterone
- Deamino Arginine Vasopressin
- Female
- Gene Expression
- Kidney Medulla
- Membrane Glycoproteins
- Membrane Transport Proteins
- Nitric Oxide Synthase
- Osmolar Concentration
- Polyuria
- Rats
- Rats, Inbred Strains
- Renal Agents
- Urea
- Urine
- Water-Electrolyte Balance
Water transport between the perilymph and endolymph is important in regulations of volume and osmotic pressure of the inner ear labyrinth. It is now known that expression of water channels (aquaporins or AQPs) in the cell membrane dramatically increases the ability of water to cross epithelial cells. The aims of the current study were to investigate the cellular localization of AQPs by immunolabeling, and to study the developmental expression and relative abundance of various subtypes of AQPs. We report here that AQP3, AQP7 and AQP9 were expressed in the inner ear. Specific subtypes of AQPs were found in discrete regions expressed by both epithelial cells and fibrocytes in cochlear and vestibular organs. Semi-quantitative measurements showed that AQP4 and AQP1 were the two most abundantly expressed AQP subtypes in the inner ear, and their expressions were dramatically upregulated during development. These data showed a highly localized and largely non-overlapping distribution pattern for different subtypes of AQPs in the inner ear, suggesting the existence of regional subtype-specific water transport pathways, and global regulation of water transport in the inner ear may require concerted actions of multiple types of AQPs.
MeSH Terms
- Aging
- Animals
- Aquaporins
- Biological Transport
- Cochlea
- Ear, Inner
- Endolymphatic Sac
- Immunohistochemistry
- Mice
- Protein Isoforms
- Vestibule, Labyrinth
- Water
The mechanisms underlying age-related polyuria were investigated in 10- and 30-mo-old female WAG/Rij rats. Urinary volume and osmolality were 3.9 /- 0.3 ml/24 h and 2,511 /- 54 mosmol/kgH(2)O in adult rats and 12.8 /- 0.8 ml/24 h and 1,042 /- 44 mosmol/kgH(2)O in senescent animals. Vasopressin V(2) receptor mRNA did not significantly differ between 10 and 30 mo, and [(3)H]vasopressin binding sites in membrane papilla were reduced by 30%. The cAMP content of the papilla was unchanged with age, whereas papillary osmolality was significantly lowered in senescent animals. The expression of aquaporin-1 (AQP1) and -4 was mostly unaltered from 10 to 30 mo. In contrast, aquaporin-2 (AQP2) and -3 (AQP3) expression was downregulated by 80 and 50%, respectively, and AQP2 was markedly redistributed into the intracellular compartment, in inner medulla of senescent animals, but not in renal cortex. These results indicate that age-related polyuria is associated with a downregulation of AQP2 and AQP3 expression in the medullary collecting duct, which is independent of vasopressin-mediated cAMP accumulation.
MeSH Terms
- Aging
- Animals
- Aquaporin 2
- Aquaporin 3
- Aquaporin 6
- Aquaporins
- Binding Sites
- Body Weight
- Cell Membrane
- Cyclic AMP
- Down-Regulation
- Drinking
- Eating
- Female
- Fluorescent Antibody Technique, Indirect
- Kidney
- Kidney Medulla
- Kidney Tubules
- Osmolar Concentration
- Polyuria
- RNA, Messenger
- Rats
- Rats, Inbred Strains
- Receptors, Vasopressin
- Vasopressins
Aquaporins (AQPs) are membrane water channel proteins expressed in various tissues in the body. We surveyed the immunolocalization of AQP3, an isoform of the AQP family, in rat epithelial tissues. AQP3 was localized to many epithelial cells in the urinary, digestive, and respiratory tracts and in the skin. In the urinary tract, AQP3 was present at transitional epithelia. In the digestive tract, abundant AQP3 was found in the stratified epithelia in the upper part, from the oral cavity to the forestomach, and in the simple and stratified epithelia in the lower part, from the distal colon to the anal canal. In the respiratory tract, AQP3 was present in the pseudostratified ciliated epithelia from the nasal cavity to the intrapulmonary bronchi. In the skin, AQP3 was present in the epidermis. Interestingly, AQP3 was present at the basal aspects of the epithelia: in the basolateral membranes in the simple epithelia and in the multilayered epithelia at plasma membranes of the basal to intermediate cells. During development of the skin, AQP3 expression commenced late in fetal life. Because these AQP3-positive epithelia have a common feature, i.e., they are exposed to an environment of possible water loss, we propose that AQP3 could serve as a water channel to provide these epithelial cells with water from the subepithelial side to protect them against dehydration. (J Histochem Cytochem 47:1275-1286, 1999)
MeSH Terms
- Aging
- Animals
- Animals, Newborn
- Antibody Specificity
- Aquaporin 3
- Aquaporins
- Digestive System
- Epithelial Cells
- Fluorescent Antibody Technique, Indirect
- Immunoblotting
- Male
- Microscopy, Immunoelectron
- Rats
- Rats, Wistar
- Respiratory System
- Skin
- Time Factors
- Urinary Tract
Developmental expression of aquaporin water transport proteins is not well understood in respiratory tract or secretory glands; here we define aquaporin protein ontogeny in rat. Expression of aquaporin-3 (AQP3), AQP4, and AQP5 proteins occurs within 2 wk after birth, whereas AQP1 first appears before birth. In most tissues, aquaporin protein expression increases progressively, although transient high-level expression is noted in distal lung (AQP4 at postnatal day 2) and trachea (AQP5 at postnatal day 21 and AQP3 at postnatal day 42). In mature animals, AQP5 is abundant in distal lung and salivary glands, AQP3 and AQP4 are present in trachea, and AQP1 is present in all of these tissues except salivary glands. Surprisingly, all four aquaporin proteins are highly abundant in nasopharynx. Unlike AQP1, corticosteroids did not induce expression of AQP3, AQP4, or AQP5 in lung. Our results seemingly implicate aquaporins in proximal airway humidification, glandular secretion, and perinatal clearance of fluid from distal airways. However, the studies underscore a need for detailed immunohistochemical characterizations and definitive functional studies.
MeSH Terms
- Adrenal Cortex Hormones
- Aging
- Amino Acid Sequence
- Animals
- Antibodies
- Aquaporin 1
- Aquaporin 3
- Aquaporin 4
- Aquaporin 5
- Aquaporins
- Betamethasone
- Embryonic and Fetal Development
- Eye
- Gene Expression Regulation, Developmental
- Ion Channels
- Lung
- Membrane Proteins
- Molecular Sequence Data
- Organ Specificity
- Peptide Fragments
- Rats
- Respiratory Physiological Phenomena
- Respiratory System
- Salivary Glands
The mRNA expression and localization of the aquaporin (AQP) family in rat kidney were examined by ribonuclease protection assay and immunohistochemistry. AQP1, AQP2, AQP3, and AQP4 mRNA were hardly detectable in 16-day gestation fetuses. AQP1 mRNA was explosively expressed at 1 wk, keeping the level throughout life. AQP2 mRNA expression was apparently noticed in 18-day fetuses and was enhanced gradually with age to reach a plateau at 4 wk. AQP3 and AQP4 mRNA expression was significantly found at birth but was not changed remarkably thereafter. AQP2 protein appeared first at the apical side of collecting duct cells in 18-day fetuses. The staining intensity at the site increased with age, and basolateral staining was added in adult rats. AQP3 was distinctly demonstrated at the basolateral side of collecting duct cells after birth, and the staining intensity was almost stable throughout life. The progressive induction of AQP2 expression in the first 4 wk after birth is presumed to contribute to the maturation of urinary concentrating capacity during the kidney development.
MeSH Terms
- Aging
- Animals
- Animals, Newborn
- Embryo, Mammalian
- Embryonic and Fetal Development
- Immunohistochemistry
- Ion Channels
- Kidney
- RNA, Messenger
- Rats
- Rats, Inbred WKY
- Water