CD34

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Hematopoietic progenitor cell antigen CD34 precursor (CD34 antigen)

Publications[править]

Comparing the Effect of TGF-β Receptor Inhibition on Human Perivascular Mesenchymal Stromal Cells Derived from Endometrium, Bone Marrow and Adipose Tissues.

Rare perivascular mesenchymal stromal cells (MSCs) with therapeutic properties have been identified in many tissues. Their rarity necessitates extensive in vitro expansion, resulting in spontaneous differentiation, cellular senescence and apoptosis, producing therapeutic products with variable quality and decreased potency. We previously demonstrated that A83-01, a transforming growth factor beta (TGF-β) receptor inhibitor, maintained clonogenicity and promoted the potency of culture-expanded premenopausal endometrial MSCs using functional assays and whole-transcriptome sequencing. Here, we compared the effects of A83-01 on MSCs derived from postmenopausal endometrium, menstrual blood, placenta decidua-basalis, bone marrow and adipose tissue. Sushi-domain-containing-2 (SUSD2 ) and CD34 CD31 CD45 MSCs were isolated. Expanded MSCs were cultured with or without A83-01 for 7 days and assessed for MSC properties. SUSD2 identified perivascular cells in the placental decidua-basalis, and their maternal origin was validated. A83-01 promoted MSC proliferation from all sources except bone marrow and only increased SUSD2 expression and prevented apoptosis in MSCs from endometrial-derived tissues. A83-01 only improved the cloning efficiency of postmenopausal endometrial MSCs (eMSCs), and expanded adipose tissue MSCs (adMSCs) underwent significant senescence, which was mitigated by A83-01. MSCs derived from bone marrow (bmMSCs) were highly apoptotic, but A83-01 was without effect. A83-01 maintained the function and phenotype in MSCs cultured from endometrial, but not other, tissues. Our results also demonstrated that cellular SUSD2 expression directly correlates with the functional phenotype.


Keywords

  • SUSD2
  • adipose tissue
  • apoptosis
  • bone marrow
  • clonogenicity
  • endometrium
  • menstrual fluid
  • perivascular mesenchymal stromal cells
  • placenta
  • senescence


ACE2/ACE imbalance and impaired vasoreparative functions of stem/progenitor cells in aging.

Aging increases risk for ischemic vascular diseases. Bone marrow-derived hematopoietic stem/progenitor cells (HSPCs) are known to stimulate vascular regeneration. Activation of either the Mas receptor (MasR) by angiotensin-(1-7) (Ang-(1-7)) or angiotensin-converting enzyme-2 (ACE2) stimulates vasoreparative functions in HSPCs. This study tested if aging is associated with decreased ACE2 expression in HSPCs and if Ang-(1-7) restores vasoreparative functions. Flow cytometric enumeration of Lin CD45 CD34 cells was carried out in peripheral blood of male or female individuals (22-83 years of age). Activity of ACE2 or the classical angiotensin-converting enzyme (ACE) was determined in lysates of HSPCs. Lin Sca-1 cKit (LSK) cells were isolated from young (3-5 months) or old (20-22 months) mice, and migration and proliferation were evaluated. Old mice were treated with Ang-(1-7), and mobilization of HSPCs was determined following ischemia induced by femoral ligation. A laser Doppler blood flow meter was used to determine blood flow. Aging was associated with decreased number (Spearman r = - 0.598, P < 0.0001, n = 56), decreased ACE2 (r = - 0.677, P < 0.0004), and increased ACE activity (r = 0.872, P < 0.0001) (n = 23) in HSPCs. Migration or proliferation of LSK cells in basal or in response to stromal-derived factor-1α in old cells is attenuated compared to young, and these dysfunctions were reversed by Ang-(1-7). Ischemia increased the number of circulating LSK cells in young mice, and blood flow to ischemic areas was recovered. These responses were impaired in old mice but were restored by treatment with Ang-(1-7). These results suggest that activation of ACE2 or MasR would be a promising approach for enhancing ischemic vascular repair in aging.


Keywords

  • ACE2
  • Aging
  • Angiotensin-(1-7)
  • Hematopoietic stem/progenitor cells
  • Ischemia


Innovative Mind-Body Intervention Day Easy Exercise Increases Peripheral Blood CD34 Cells in Adults.

Mind-body interventions (MBIs) have many health benefits, such as reducing stress, modulating blood pressure, and improving sleep and life quality. The long-term practice of Tai chi, an MBI, also increases the number of CD34 cells, which are surface markers of hematopoietic stem cells, so prolonged Tai chi practice may have antiaging effects. We developed the day easy exercise (DEE), an innovative MBI, that is easy to learn and requires only a small exercise area and a short practice time. The aim of this study was to explore whether DEE, like Tai chi, has antiaging effects after short-term practice. Total 44 individuals (25 to 62 years old) with or without 3-month DEE practice were divided into young- and middle-aged groups (≤30 and >30 years old) and peripheral blood was collected at 0, 1, 2, and 3 months for analysis of CD34 cells. The number of CD34 cells in peripheral blood remained unchanged in control young- and middle-aged groups. After DEE, the number of CD34 cells in peripheral blood was increased over time in both young- and middle-aged groups. For young-aged adults, the cell number was markedly increased by threefold at 3 months after DEE, and for middle-aged adults, the increase was significant from the first month. DEE practice indeed increased the number of CD34 cells in peripheral blood and the increase was more significant for older people in a shorter time. This is the first study to provide evidence that the DEE may have antiaging effects and could be beneficial for older people.


Keywords

  • CD34 cells
  • aging
  • day easy exercise
  • mind–body intervention


Human Thymic Involution and Aging in Humanized Mice.

Thymic involution is an important factor leading to the aging of the immune system. Most of what we know regarding thymic aging comes from mouse models, and the nature of the thymic aging process in humans remains largely unexplored due to the lack of a model system that permits longitudinal studies of human thymic involution. In this study, we sought to explore the potential to examine human thymic involution in humanized mice, constructed by transplantation of fetal human thymus and CD34 hematopoietic stem/progenitor cells into immunodeficient mice. In these humanized mice, the human thymic graft first underwent acute recoverable involution caused presumably by transplantation stress, followed by an age-related chronic form of involution. Although both the early recoverable and later age-related thymic involution were associated with a decrease in thymic epithelial cells and recent thymic emigrants, only the latter was associated with an increase in adipose tissue mass in the thymus. Furthermore, human thymic grafts showed a dramatic reduction in [i]FOXN1[/i] and [i]AIRE[/i] expression by 10 weeks post-transplantation. This study indicates that human thymus retains its intrinsic mechanisms of aging and susceptibility to stress-induced involution when transplanted into immunodeficient mice, offering a potentially useful [i]in vivo[/i] model to study human thymic involution and to test therapeutic interventions.


Keywords

  • aging
  • human
  • humanized mouse
  • recent thymic emigrants
  • thymus involution


Coinhibition of activated p38 MAPKα and mTORC1 potentiates stemness maintenance of HSCs from SR1-expanded human cord blood CD34 cells via inhibition of senescence.

The stemness of ex vivo expanded hematopoietic stem cells (HSCs) is usually compromised by current methods. To explore the failure mechanism of stemness maintenance of human HSCs, which were expanded from human umbilical cord blood (hUCB) CD34 cells, by differentiation inhibitor Stem Regenin 1 (SR1), an antagonist of aryl hydrocarbon receptor, we investigated the activity of p38 mitogen-activated protein kinase α (p38 MAPKα, p38α) and mammalian target of rapamycin complex 1 (mTORC1), and their effect on SR1-expanded hUCB CD34 cells. Our results showed that cellular senescence occurred in the SR1-expanded hUCB CD34 cells in which p38α and mTORC1 were successively activated. Furthermore, their coinhibition resulted in a further decrease in hUCB CD34 cell senescence without an effect on apoptosis, promoted the maintenance of expanded phenotypic HSCs without differentiation inhibition, increased the hematopoietic reconstitution ability of multiple lineages, and potentiated the long-term self-renewal capability of HSCs from SR1-expanded hUCB CD34 cells in NOD/Shi-scid/IL-2Rγ mice. Our mechanistic study revealed that senescence inhibition by our strategy was mainly attributed to downregulation of the splicesome, proteasome formation, and pyrimidine metabolism signaling pathways. These results suggest that coinhibition of activated p38α and mTORC1 potentiates stemness maintenance of HSCs from SR1-expanded hUCB CD34 cells via senescence inhibition. Thus, we established a new strategy to maintain the stemness of ex vivo differentiation inhibitor-expanded human HSCs via coinhibition of multiple independent senescence initiating signal pathways. This senescence inhibition-induced stemness maintenance of ex vivo expanded HSCs could also have an important role in other HSC expansion systems.


Keywords

  • HSC stemness maintenance
  • Stem Regenin 1
  • cellular senescence
  • ex vivo expansion
  • human cord blood CD34 cells
  • mammalian target of rapamycin complex 1
  • p38 mitogen-activated protein kinase α


Bulk and single-cell gene expression analyses reveal aging human choriocapillaris has pro-inflammatory phenotype.

The human choroidal vasculature is subject to age-related structural and gene expression changes implicated in age-related macular degeneration (AMD). In this study, we performed both bulk and single-cell RNA sequencing on infant (n = 4 for bulk experiments, n = 2 for single-cell experiments) and adult (n = 13 for bulk experiments, n = 6 for single-cell experiments) human donors to characterize how choroidal gene expression changes with age. Differential expression analysis revealed that aged choroidal samples were enriched in genes encoding pro-inflammatory transcription factors and leukocyte transendothelial cell migration adhesion proteins. Such genes were observed to be differentially expressed specifically within choroidal endothelial cells at the single-cell level. Immunohistochemistry experiments support transcriptional findings that CD34 is elevated in infant choriocapillaris endothelial cells while ICAM-1 is enriched in adults. These results suggest several potential drivers of the pro-inflammatory vascular phenotype observed with advancing age.

MeSH Terms

  • Age Factors
  • Aged
  • Aged, 80 and over
  • Aging
  • Choroid
  • Endothelial Cells
  • Female
  • Gene Expression Regulation
  • Humans
  • Infant
  • Infant, Newborn
  • Inflammation
  • Inflammation Mediators
  • Macular Degeneration
  • Male
  • Middle Aged
  • Phenotype
  • Sequence Analysis, RNA
  • Single-Cell Analysis

Keywords

  • Age-related macular degeneration
  • Choriocapillaris
  • Choroid
  • Infant
  • Pericytes
  • Single-cell


Phenotypic Analysis of the Mouse Hematopoietic Hierarchy Using Spectral Cytometry: From Stem Cell Subsets to Early Progenitor Compartments.

Phenotypic analysis by flow cytometry is one of the most utilized primary tools to study the hematopoietic system. Here, we present a complex panel designed for spectral flow cytometry that allows for the in-depth analysis of the mouse hematopoietic stem and progenitor compartments. The developed panel encompasses the hematopoietic stem cell (HSC) compartment, an array of multipotent progenitors with early marks of lineage specification and a series of progenitors associated with lymphoid, granulo-macrophagic, megakaryocytic and erythroid lineage commitment. It has a built-in redundancy for key markers known to decipher the fine architecture of the HSC compartment by segregating subsets with different functional potential. As a resource, we used this panel to provide a snapshot view of the evolution of these phenotypically defined hematopoietic compartments during the life of the animals. We show that by using a spectral cytometer, this panel is compatible with the analysis of GFP-expressing gene-reporter mice across the hematopoietic system. We leverage this tool to determine how previously described markers such as CD150, CD34, CD105, CD41, ECPR, and CD49b define specific HSC subsets and confirm that high expression of the transcription factor Gfi1 is a hallmark of the most primitive HSC compartment. Altogether, our results provide a convenient protocol to obtain in one analysis a more extensive view of the hematopoietic architecture in mouse models. Our results could also serve as a base for further development of high-end panels leveraging spectral flow cytometry beyond the 15-fluorochrome panel presented in this report. © 2020 International Society for Advancement of Cytometry.


Keywords

  • aging
  • gene-reporter mouse model
  • hematopoietic progenitors
  • hematopoietic stem cell compartments
  • immunophenotyping
  • mouse hematopoietic hierarchy
  • spectral flow cytometry


Mesenchymal stem cells repair bone marrow damage of aging rats and regulate autophagy and aging genes.

The current study investigated the role of mesenchymal stem cells (MSCs) in repairing senile bone marrow injury and the underlying mechanism. Adenoviral vectors expressing green fluorescent protein (GFP) were used to label MSCs. The level of malondialdehyde (MDA) and activity of superoxide dismutase (SOD) were detected by thiobarbituric acid (TBA) and xanthine oxidation (XTO) methods. The proportions of CD34, CD3 cells, cell proliferation and apoptosis were determined by flow cytometry, Cell counting kit (CCK)-8 and comet assay. Tissues were stained by haematoxylin-eosin (HE) staining and their changes were observed under a transmission electron microscopy. Expression levels of age-related and autophagy-related genes were detected by RT-qPCR and Western Blot. MSCs were successfully implanted into the bone marrow of aging rats. We found that the SOD activity was increased and MDA content was reduced in MSCs group. The proportions of CD34 cells were significantly more in the MSCs group than those in the Model group, and bone marrow cell colony formation and cell viability were both greatly increased in MSCs group. The proportions of CD3 cells and level of Vascular endothelial growth factor (VEGF) were increased significantly, while IL-6 level was reduced greatly in MSCs group. Moreover, the bone marrow tissues of the model group were severely damaged, but those of the MSCs group were significantly improved. In addition, MSCs were involved in regulation of aging-related genes and autophagy-related genes. In conclusion, our findings showed that MSCs can repair bone marrow damage in aging rats, and regulate aging- and autophagy-related genes and immune response. SIGNIFICANCE: This study investigated the role of MSCs in the repair of senile bone marrow injury and the underlying mechanism. The effects of MSCs on physiological and biochemical indicators, cell function, tissue structure differences and pathological changes in aging rats were studied. It was found that MSCs can repair bone marrow damage in aging rats. MSCs regulate aging and autophagy-related genes and its involvement in immune response. Our findings improve the understandings on the regulatory mechanism of MSCs and provide key evidence for the study of MSCs in bone marrow repair.


Keywords

  • aging
  • autophagy
  • bone marrow injury
  • mesenchymal stem cells
  • repair


Effects of continuous exposure to low concentration of ClO gas on the growth, viability, and maintenance of undifferentiated MSCs in long-term cultures.

Hygienic management is more important in the manufacturing of cell products than in the production of chemical agents, because cell material and final product cannot be decontaminated. On the other hand, especially in the selection of hygienic agent, the adverse effects on the cells must be considered as well as the decontamination effect. ClO is a potent disinfectant, which is now expected as a safe and effective hygienic agent in the field of cell production. In this study, we investigated the effects of low dose ClO gas in the atmosphere of CO incubator on the characteristics of MSCs cultured in it. First, we installed a ClO generator to a CO incubator for cell culture in which a constant level of ClO can be maintained. After culturing human cord derived MSCs in the CO incubator, the characteristics of cells were analyzed. Continuous exposure to 0.05 ppmv of ClO gas did not affect cell proliferation until at least 8th passage. In the FACS analysis, antigens usually expressed on MSCs, CD105, CD90, CD44, CD73 and CD29, were positively observed, but differentiation markers, CD11b and CD34, were little expressed on the MSCs exposed to 0.05 ppmv or 0.1 ppmv of ClO gas just as on the control cells. Also in the investigation for cell death, 0.05 ppmv and 0.1 ppmv of ClO gas little affected the viability, apoptosis or necrosis of MSCs. Furthermore, we assessed senescence using SA-β-gal staining. Although the frequency of stained cells cultured in 0.1 ppmv of ClO gas was significantly increased than that of not exposed cells, the stained cells in 0.05 ppmv were rare and their frequency was almost the same as that in control. All these results indicate that, although excessive concentration of ClO gas induces senescence but neither apoptosis nor cell differentiation, exposure to 0.05 ppmv of ClO gas little affected the characteristics of MSCs. In this study we demonstrate that continuous exposure to appropriate dose of ClO gas can be safely used as decontamination agent in cell processing facilities.


Keywords

  • Cell processing
  • Chlorine dioxide (ClO2)
  • ClO2, chlorine dioxide
  • EPA, Environmental Protection Agency
  • FDA, Food and Drug Administration
  • H2O2, hydrogen peroxide
  • HEPA, high efficiency particulate air
  • Hygienic management
  • MSCs, mesenchymal stem cells
  • Mesenchymal stem cells (MSCs)
  • OSHA, Occupational Safety and Health Administration
  • PMD Act, Pharmaceuticals and Medical Devices Act
  • Senescence
  • TWA, time weight average
  • WHO, World Health Organization


Immune cell extracellular vesicles and their mitochondrial content decline with ageing.

Although the mechanisms of action are not fully understood, extracellular vesicles (EVs) have emerged as key indicators and effectors of immune function. Characterizing circulating EVs associated with stem and immune cells across the lifespan of healthy individuals could aid an understanding of immunosenescence, a process of age-related decline of cells in both adaptive and innate immune systems. Using high resolution multicolor flow cytometry, we identified three major subsets of EVs of varying sizes in healthy control (HC) plasma. Multiple plasma EVs associated with immune cells declined with ageing in HCs. In addition, we observed age-associated declines of respiring mitochondria cargo in EVs of several types of immune cells, suggesting that these parent cells may experience a decline in mitophagy or a mitochondrial dysfunction-induced immunosenescence. By contrast, the number of CD34 hematopoietic stem cell-associated EVs were high and carried respiring mitochondria, which did not decline with age. As demonstrated here, multicolor flow cytometry simultaneously measures plasma EV size, surface markers and cargo that reflect biological processes of specific cell types. The distinct surface markers and cytokine cargo of plasma EVs suggest that they may carry different bio-messages and originate by different biogenesis pathways.


Keywords

  • Ageing
  • Apoptotic bodies
  • Exosomes
  • Extracellular vesicles
  • Immune cells
  • Immunosenescence
  • Inflammageing
  • Microvesicles
  • Mitochondria


Young and elderly oral squamous cell carcinoma patients present similar angiogenic profile and predominance of M2 macrophages: Comparative immunohistochemical study.

M2 macrophages are often detected in oral squamous cell carcinoma (OSCC), which, influenced by hypoxic conditions, appear to have high angiogenesis-inducing capacity. However, the effects of immunosenescence on tumor-associated macrophages (TAMs) and angiogenesis in OSCC are unknown. Fifty-seven OSCCs were divided into 3 groups (I: <40 years [n = 17]; II: 40-65 years [n = 20]; III: >65 years [n = 20]). Immunohistochemistry for CD68 and CD163 (TAMs), and CD34 and D2-40 for microvessel density (MVD), microvessel area (MVA), and total vascular area (TVA) were performed. All groups showed similar clinicopathological and immunohistochemical findings. Similar CD68 and CD163 expression, confirmed a M2 phenotype. MVD, MVA, and TVA were similar, however, with significant predominance of blood vessels. No significant correlation between macrophage and angiogenic markers was observed. A similar TAM and angiogenesis profile suggests the participation of other mechanisms, instead immunosenescence, in young and elderly OSCC patients.

MeSH Terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antigens, CD
  • Antigens, Differentiation, Myelomonocytic
  • Carcinoma, Squamous Cell
  • Female
  • Humans
  • Immunohistochemistry
  • Immunosenescence
  • Macrophages
  • Male
  • Middle Aged
  • Mouth Neoplasms
  • Neovascularization, Pathologic
  • Receptors, Cell Surface
  • Tumor Microenvironment

Keywords

  • M1 and M2 macrophages
  • angiogenesis
  • immunohistochemistry
  • immunosenescence
  • oral squamous cell carcinoma


HIV-mediated immune aging in young adults infected perinatally or during childhood.

HIV-infected patients progressing towards disease present a premature immune aging profile, characterized by the exhaustion of lymphopoiesis. The development of these anomalies may be prevented in young HIV-infected patients owing to their robust immune resources and lymphocyte regeneration capacities. An immunomonitoring substudy was designed for young adults aged between 18 and 25 years, living with HIV since childhood included in the national ANRS Co19 COVERTE Cohort. We compared markers associated with immune aging, including the frequency of circulating hematopoietic progenitors and the phenotype of lymphocyte populations, with those of patients infected with HIV in adulthood. HIV-infected young adults displayed decreasing numbers of CD34 hematopoietic progenitors and mature lymphocytes, indicative of general lymphopenia and reminiscent of the alterations found in patients infected in adulthood or uninfected elderly people. This highlights the strong impact of HIV on the immune system despite patient's young age at infection. Immune aging-related alterations were particularly obvious in young patients who presented high viral loads. HIV-infected young adults can present increased markers of immune activation and senescence, related to uncontrolled viral replication. This highlights the issue of noncompliance to antiretroviral therapy in patients at a young age, resulting in loss of viral control, premature immunosenescence, and potentially irreversible damage of their lymphopoietic system.

MeSH Terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Biomarkers
  • CD4 Lymphocyte Count
  • CD4-Positive T-Lymphocytes
  • CD8-Positive T-Lymphocytes
  • Cell Separation
  • Disease Progression
  • Female
  • Flow Cytometry
  • HIV Infections
  • HIV-1
  • Hematopoietic Stem Cells
  • Humans
  • Immunosenescence
  • Lymphopoiesis
  • Male
  • Middle Aged
  • Prospective Studies
  • Viral Load
  • Virus Replication
  • Young Adult


Immunophenotypic characterization, multi-lineage differentiation and aging of zebrafish heart and liver tissue-derived mesenchymal stem cells as a novel approach in stem cell-based therapy.

Mesenchymal stem cells (MSCs) are a good model for preclinical and clinical investigations, and alternative sources of MSCs are subject to intensive experiments. In this study, mesenchymal stem cells (MSCs) were isolated from heart and liver tissue of Zebrafish (Danio rerio). The flow-cytometry as well as RT-PCR were used to analyze the expression of a panel of cell surface markers CD44, CD90, CD31 and CD34. In the following, alizarin red, oil red-O and toluidine blue staining were carried out to evaluate the multi-lineage differentiation of zebrafish heart and liver tissue-derived MSCs. Subsequently, the gene and protein expression of Oct4, Sox2 and Nanog as pluri-potent markers were analyzed by RT-PCR and western blotting, respectively. In addition, MTT assay was used for cell proliferation potential and population doubling time (PDT) assessment. Also, the aging of cells was investigated by β-galactosidase activity assay. The results showed that, like other MSCs, zebrafish heart and liver tissue-derived MSCs were positive for mesenchymal, negative for hematopoietic markers and expressed pluripotent markers Oct4, Sox2 and Nanog. Moreover, these cells were differentiated to osteocyte, adipocyte, and chondrocyte lineages following directed differentiation. It was found that PDT of zebrafish heart and liver tissue-derived MSCs were 50.67 and 46.61 h, respectively. These cells had significantly more rapid growth on day 4. Our results show that zebrafish heart and liver tissue-derived MSCs exhibited typical MSC characteristics including fibroblast morphology, multi-lineage differentiation capacity, pluripotency potential and expression of a typical set of classic MSC surface markers.

MeSH Terms

  • Aging
  • Animals
  • Cell Differentiation
  • Cell Lineage
  • Cell Proliferation
  • Heart
  • Immunophenotyping
  • Liver
  • Mesenchymal Stem Cells
  • Myocardium
  • Regenerative Medicine
  • Zebrafish

Keywords

  • Characterization
  • Multi-lineage differentiation
  • Regenerative medicine
  • Zebrafish heart and liver tissue-derived MSCs


Cardio-ankle vascular index and circulating CD34-positive cell levels as indicators of endothelial repair activity in older Japanese men.

The cardio-ankle vascular index (CAVI) reflects functional arterial stiffness, which is related to endothelial dysfunction. CD34-positive cells carry out an important function in endothelial repair. However, there have been no reports assessing the association between CAVI and the number of circulating CD34-positive cells. We carried out a cross-sectional study of 249 Japanese men, aged 60-69 years, who underwent annual health checkups between 2013 and 2015. As individuals with high levels of circulating CD34-positive cells might indicate the influence of consumptive reduction of circulating CD34-positive cells as a result of aggressive endothelial repair, participants were stratified by circulating CD34-positive cell levels, using the median value in this population (0.95 cells/μL) as the cut-off. For participants with low circulating CD34-positive cell levels, logarithmic values of circulating CD34-positive cells were inversely associated with CAVI (multivariable standardized parameter estimate [β] = -0.22, P = 0.014), but not for participants with high levels (β = -0.04, P = 0.638). In addition, even when no significant associations between CAVI and carotid intima-media thickness were detected for participants with low circulating CD34-positive cell levels (β = -0.02, P = 0.865), significant positive associations were identified for participants with high levels (β = 0.22, P = 0.028). As circulating CD34-positive cell count might indicate endothelial repair activity, the present results show that CAVI is affected by insufficient endothelial repair in individuals with low circulating CD34-positive cell counts. Our results also show that a positive association between CAVI and carotid intima-media thickness exists only in individuals with aggressive endothelial repair, which indicates the presence of organic arterial disease, such as atherosclerosis. Geriatr Gerontol Int 2019; 19: 557-562.

MeSH Terms

  • Aged
  • Aging
  • Ankle
  • Antigens, CD34
  • Biomarkers
  • Cross-Sectional Studies
  • Endothelium, Vascular
  • Humans
  • Japan
  • Male
  • Middle Aged
  • Vascular Stiffness

Keywords

  • CD34-positive cell
  • cardio-ankle vascular index
  • carotid intima-media thickness
  • endothelial repair


Role of apoptotic, autophagic and senescence pathways in minor salivary gland adenoid cystic carcinoma.

Adenoid cystic carcinoma (ACC) is a salivary gland malignancy with poor long-term survival, which warrants studies aimed at clarifying the pathogenesis of this disease in order to widen the scope of therapeutic options currently available. Alterations in regulatory mechanisms relating to vascular support, cell death and autophagy are important pathways for tumor growth in cancer. Thus, the present study aimed to access vascular supply, apoptosis, autophagy and cell senescence in ACC of minor salivary glands. We analyzed 25 cases of minor salivary gland ACC by immunohistochemistry using anti-CD34, anti-CD105, anti-D2-40, anti-Bax, anti-Bcl-2, anti-Beclin-1, anti-LC3B, anti-p21 and anti-p16. Microvessel density was low and based on anti-CD34, anti-CD105 and anti-D2-40 immunostaining. There was positivity for anti-CD34, anti-Bcl-2, anti-Beclin, anti-LC3B and anti-p21 and a positive correlation between Bcl-2 and Beclin (p = 0.014). Our results showed that ACC does not depend on neo-angiogenesis and is probably associated to anti-apoptotic, autophagic and anti-senescence events.

MeSH Terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Apoptosis
  • Autophagy
  • Carcinoma, Adenoid Cystic
  • Cellular Senescence
  • Female
  • Humans
  • Male
  • Middle Aged
  • Salivary Gland Neoplasms
  • Salivary Glands, Minor
  • Young Adult

Keywords

  • Adenoid cystic carcinoma
  • Angiogenesis
  • Apoptosis
  • Autophagy
  • Senescence


Dynamic regulation of NOTCH1 activation and Notch ligand expression in human thymus development.

T-cell development is a complex dynamic process that relies on ordered stromal signals delivered to thymus-seeding progenitors that migrate throughout different thymus microenvironments (TMEs). Particularly, Notch signaling provided by thymic epithelial cells (TECs) is crucial for T-cell fate specification and generation of mature T cells. Four canonical Notch ligands (Dll1, Dll4, Jag1 and Jag2) are expressed in the thymus, but their spatial distribution in functional TMEs is largely unknown, especially in humans, and their impact on Notch1 activation during T-lymphopoiesis remains undefined. Based on immunohistochemistry and quantitative confocal microscopy of fetal, postnatal and adult human and mouse thymus samples, we show that spatial regulation of Notch ligand expression defines discrete Notch signaling niches and dynamic species-specific TMEs. We further show that Notch ligand expression, particularly DLL4, is tightly regulated in cortical TECs during human thymus ontogeny and involution. Also, we provide the first evidence that NOTCH1 activation is induced [i]in vivo[/i] in CD34 progenitors and developing thymocytes at particular cortical niches of the human fetal and postnatal thymus. Collectively, our results show that human thymopoiesis involves complex spatiotemporal regulation of Notch ligand expression, which ensures the coordinated delivery of niche-specific NOTCH1 signals required for dynamic T-cell development.

MeSH Terms

  • Adolescent
  • Adult
  • Aging
  • Animals
  • Antigens, CD34
  • Child
  • Fetus
  • Gene Expression Regulation, Developmental
  • Humans
  • Infant
  • Infant, Newborn
  • Ligands
  • Mice
  • Mice, Inbred C57BL
  • Organogenesis
  • Receptor, Notch1
  • Serrate-Jagged Proteins
  • Signal Transduction
  • Stem Cells
  • Stromal Cells
  • Thymocytes
  • Thymus Gland

Keywords

  • Human
  • Notch ligands
  • Thymus microenvironment
  • γδ T cells


Therapeutic efficacy of olfactory stem cells in rotenone induced Parkinsonism in adult male albino rats.

Olfactory stem cells (OSCs) are found in the olfactory mucosa and olfactory bulb and have the capacity to proliferate and differentiate along multiple tissue lineages. Rotenone; widely used insecticide has a neurodegenerative effect on the dopaminergic cells of substantia nigra (SN) of midbrain producing Parkinsonism. The aim of this study is to isolate rat OSCs from olfactory mucosa and olfactory bulb, culture these OSCs in suitable medium to allow for their proliferation to be used in the treatment of Parkinsonism induced by rotenone. The characteristics of OSCs, the effects of rotenone on the SN of midbrain and the curative effect of OSCs on the substantia nigra were determined morphologically, immunohistochemically, and by transmission electron microscopy. PKH 26; immunofluorescent dye was used as a cell tracer to locate the transplanted cells in host midbrain. OSCs were spindle shaped with irregular processes, and were positive for CD44 and Nestin and negative for CD34. Subcutaneous rotenone produced Parkinsonism through producing degeneration of the dopaminergic cells of SN of the midbrain. Transplantation of OSCs produced restoration of the normal structure of SN and dopaminergic cells and improves the clinical manifestations of Parkinsonism. These results indicate that, the isolated rat OSCs can proliferate and expand in vitro when culture in suitable medium and these cells can exert therapeutic effects in Parkinsonism by recruitment in SN and restoration of the structure and function of dopaminergic cells.

MeSH Terms

  • Aging
  • Animals
  • Cells, Cultured
  • Male
  • Mesencephalon
  • Motor Activity
  • Olfactory Bulb
  • Parkinsonian Disorders
  • Rats
  • Rotenone
  • Stem Cell Transplantation
  • Stem Cells
  • Treatment Outcome
  • Tyrosine 3-Monooxygenase

Keywords

  • Characterization
  • Isolation
  • Olfactory stem cells
  • Parkinsonism
  • Rotenone


Gender and age-related cell compositional differences in C57BL/6 murine adipose tissue stromal vascular fraction.

Adipose tissue is now recognized as a functional organ that contains cellular heterogeneity and diversity within anatomical depots. The stromal vascular fraction (SVF) of adipose contains endothelial progenitors, fibroblasts, lymphocytes, monocyte/macrophages, pericytes, pre-adipocytes, and stromal/stem cells, among others. In recent years, there has been a growing appreciation of the influence of age and gender in the field of stem cell biology. Yet few studies have evaluated the influence of biological age or sex on either SVF cell heterogeneity or immunophenotype. To address this issue, the current study has compared the flow cytometric characteristics between murine SVF of inguinal (iWAT), epidydimal (eWAT), and brown (BAT) adipose tissue of male and female, as well as young (6-8 week) and middle-aged (8-12 month) male C57BL/6 mice. Murine gender comparisons revealed male iWAT expressed higher percentages of leukocyte and CD34 ASC-like sub-populations than female iWAT. Murine age comparisons revealed younger male iWAT, eWAT, and BAT SVF all contained a significantly higher percentage of pre-adipocytes, HSC-like cells, CD25 , and FoxP3 T-regulatory cells compared to SVF from middle-aged male mice. These findings highlight the potential contribution of biological variables on adipose-derived cell applications and experimental outcomes.

MeSH Terms

  • Adipose Tissue
  • Aging
  • Animals
  • Cell Differentiation
  • Female
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Sex Characteristics
  • Stromal Cells

Keywords

  • C57BL/6 mice
  • Stromal vascular fraction (SVF) cells
  • adipose tissue
  • age analysis
  • cell composition
  • gender analysis
  • regenerative medicine


Endothelial progenitor cells from aged subjects display decreased expression of sirtuin 1, angiogenic functions, and increased senescence.

Studies have demonstrated that aging is associated with a substantial decline in numbers and angiogenic activity of endothelial progenitor cells (EPCs). In view of senescence being an important regulator of age-related cell survival and function, in the current study, we correlated EPCs numbers and functions with their senescence status and mechanisms in young and elderly subjects. Healthy young subjects (n = 30, below 60 y) and old subjects (n = 30, equal to or above 60 y) participated in the study. Subjects had no significant disease or risk factors of disease and aging was the only risk factor in the aged subjects. Enumeration of CD34-vegfr2 dual positive EPCs was performed. The ex vivo culture of EPCs was done to study colony formation, migration, and senescence-associated beta-galactosidase activity. The expression of cell cycle and senescence regulatory proteins including, p53, p21, and sirtuin 1 (SIRT1), a deacetylase protein was studied in cultured EPCs by RT-PCR and immunofluorescence staining. In vivo proliferation, ex vivo colonies, migration, and secretory ability of EPCs was significantly higher in young subjects than that in elderly subjects. EPCs in old subjects showed enhanced senescence and decreased expression of SIRT1 in comparison to that observed in young subjects. An inhibition of SIRT1 in EPCs of young subjects led to significant increase in senescence and reduction of cell differentiation. The study suggests that EPCs have decreased proliferation and functions in aged subjects due to increased senescence which may be attributable to decreased expression of SIRT1.

MeSH Terms

  • Adult
  • Age Factors
  • Aged
  • Cell Cycle
  • Cell Division
  • Cell Movement
  • Cells, Cultured
  • Cellular Senescence
  • Endothelial Progenitor Cells
  • Female
  • Humans
  • Male
  • MicroRNAs
  • Middle Aged
  • Signal Transduction
  • Sirtuin 1
  • Stem Cells
  • Transcriptome
  • Young Adult
  • beta-Galactosidase

Keywords

  • aging
  • angiogenesis
  • endothelial progenitor cells (EPCs)
  • p53
  • senescence
  • sirtuin 1 (SIRT1)


Precise Intradermal Injection of Nanofat-Derived Stromal Cells Combined with Platelet-Rich Fibrin Improves the Efficacy of Facial Skin Rejuvenation.

The rejuvenation properties of nanofat grafting have been described in recent years. However, it is not clear whether the clinical efficacy of the procedure is attributable to stem cells or linked to other components of adipose tissue. In this study we isolated nanofat-derived stem cells (NFSCs) to observe their biological characteristics and evaluate the efficacy of precise intradermal injection of nanofat combined with platelet-rich fibrin (PRF) in patients undergoing facial rejuvenation treatment. Third-passage NFSCs were isolated and cultured using a mechanical emulsification method and their surface CD markers were analyzed by flow cytometry. The adipogenic and osteogenic nature and chondrogenic differentiation capacity of NFSCs were determined using Oil Red O staining, alizarin red staining, and Alcian blue staining, respectively. Paracrine function of NFSCs was evaluated by enzyme-linked immunosorbent assay (ELISA) at 1, 3, 7, 14, and 28 days after establishing the culture. Then, the effects of PRF on NFSC proliferation were assessed in vitro. Finally, we compared the outcome in 103 patients with facial skin aging who underwent both nanofat and intradermal PRF injection (treatment group) and 128 patients who underwent hyaluronic acid (HA) injection treatment (control group). Outcomes in the two groups were compared by assessing pictures taken at the same angle before and after treatment, postoperative recovery, incidence of local absorption and cysts, and skin quality before treatment, and at 1, 12, 24 months after treatment using the VISIA Skin Image Analyzer and a SOFT5.5 skin test instrument. NFSCs expressed CD29, CD44, CD49d, CD73, CD90, and CD105, but did not express CD34, CD45, and CD106. NFSCs also differentiated into adipocytes, osteoblasts, and chondrocytes under appropriate induction conditions. NFSCs released large amounts of growth factors such as VEGF, bFGF, EGF, and others, and growth factor levels increased in a time-dependent manner. At the same time, PRF enhanced proliferation of NFSCs in vitro in a dose-dependent manner, and the growth curves under different concentrations of PRF all showed plateaus 6d after seeding. Facial skin texture was improved to a greater extent after combined injection of nanofat and PRF than after control injection of HA. The nanofat-PRF group had a higher satisfaction rate. Neither treatment caused any complications such as infection, anaphylaxis, or paresthesia during long-term follow-up. NFSCs demonstrate excellent multipotential differentiation and paracrine function, and PRF promotes proliferation of NFSCs during the early stage after seeding. Both nanofat-PRF and HA injection improve facial skin status without serious complications, but the former was associated with greater patient satisfaction, implying that nanofat-PRF injection is a safe, highly effective, and long-lasting method for skin rejuvenation.

MeSH Terms

  • Adipose Tissue
  • Adult
  • Cell Proliferation
  • Cells, Cultured
  • Face
  • Female
  • Humans
  • Injections, Intradermal
  • Intercellular Signaling Peptides and Proteins
  • Male
  • Middle Aged
  • Platelet-Rich Fibrin
  • Rejuvenation
  • Skin Aging
  • Skin Physiological Phenomena
  • Stromal Cells
  • Young Adult

Keywords

  • Facial skin aging
  • Nanofat-derived stem cells
  • Platelet-rich fibrin
  • Rejuvenation
  • Stromal vascular fraction


Human nail stem cells are retained but hypofunctional during aging.

The nail is a continuous skin appendage. Cells located around the nails, which display coordinated homeostatic dynamics and release a flow of stem cells in response to regeneration, have been identified in mice. However, very few studies regarding human nail stem cells exist in the literature. Using specimens isolated from humans, we detected an unreported population of cells within the basal layer of postnatal human nail proximal folds (NPFs) and the nail matrix around the nail root. These cells were multi-expressing and expressed stem cell markers, such as keratin 15 (K15), keratin 14 (K14), keratin 19 (K19), CD29, CD34, and leucine-rich repeat-containing G protein-coupled receptor 6 (Lgr6). These cells were very similar to mouse nail stem cells in terms of cell marker expression and their location within the nail. We also found that the putative nail stem cells maintained their abundance with advancing age, but cell proliferation and nail growth rate were decreased on comparison of young and aged specimens. To summarize, we found a putative population of stem cells in postnatal human nails located at NPFs and the nail matrix. These cells may have potential for cell differentiation and be capable of responding to injury, and were retained, but may be hypofunctional during aging.

MeSH Terms

  • Aging
  • Animals
  • Biomarkers
  • Cell Differentiation
  • Humans
  • Mice
  • Nails
  • Regeneration
  • Stem Cells

Keywords

  • Aging
  • Human nail
  • Regeneration
  • Stem cell


Hair Follicle Stem Cell Faith Is Dependent on Chromatin Remodeling Capacity Following Low-Dose Radiation.

The main function of the skin, to protect against the environment, is supported by the activity of different stem cell populations. The main focus of this study was elucidating the coping mechanisms of stem cells against the stimulation of constant exposure to genotoxic stresses, both endogenous and exogenous, to ensure long-term function. Investigation of various mouse strains, differing in their DNA repair capacity, enables us to clarify fractionated low-dose irradiation (LDR)-induced consequences for different stem cell populations of the murine hair follicle (HF) in their physiological stem cell niche. Using microscopic techniques combined with flow cytometry, we could show that LDR induces accumulation of persisting; pKu70-independent 53BP1-foci ("chromatin-alterations") in heterochromatic regions of the HF stem cells (HFSCs). These remaining chromatin-alterations result in varying stem cell consequences. CD34-positive HFSCs react by ataxia telangiectasia mutated-dependent, premature senescence, which correlates with global chromatin compaction, whereby apoptosis is prevented by the activity of DNA-dependent protein kinase catalytic subunit. However, distinctively highly damaged HFSCs seem to be sorted out of the niche by differentiation, transferring their chromatin-alterations to more proliferative G protein-coupled receptor 5-positive stem cells. Consequentially, the loss of basal HFSCs is compensated by increased proliferation within the stem cell pool. Despite the initial success of these mechanisms in stem cell population maintenance, the combined effect of the chromatin-alterations and the modification in stem cell pool composition may lead to downstream long-term functional loss of tissue or organs. Stem Cells 2018;36:574-588.

MeSH Terms

  • Animals
  • Cell Proliferation
  • Chromatin Assembly and Disassembly
  • Dose-Response Relationship, Radiation
  • Gamma Rays
  • Hair Follicle
  • Mice
  • Mice, Transgenic
  • Stem Cells

Keywords

  • Adult stem cells
  • Cell differentiation
  • Chromatin
  • DNA damage
  • Radiation
  • Senescence


Developmental differences between neonatal and adult human erythropoiesis.

Studies of human erythropoiesis have relied, for the most part, on the in vitro differentiation of hematopoietic stem and progenitor cells (HSPC) from different sources. Here, we report that despite the common core erythroid program that exists between cord blood (CB)- and peripheral blood (PB)-HSPC induced toward erythroid differentiation in vitro, significant functional differences exist. We undertook a comparative analysis of human erythropoiesis using these two different sources of HSPC. Upon in vitro erythroid differentiation, CB-derived cells proliferated 4-fold more than PB-derived cells. However, CB-derived cells exhibited a delayed kinetics of differentiation, resulting in an increased number of progenitors, notably colony-forming unit (CFU-E). The phenotypes of early erythroid differentiation stages also differed between the two sources with a significantly higher percentage of IL3R GPA CD34 CD36 cells generated from PB- than CB-HSPCs. This subset was found to generate both burst-forming unit (BFU-E) and CFU-E colonies in colony-forming assays. To further understand the differences between CB- and PB-HSPC, cells at eight stages of erythroid differentiation were sorted from each of the two sources and their transcriptional profiles were compared. We document differences at the CD34, BFU-E, poly- and orthochromatic stages. Genes exhibiting the most significant differences in expression between HSPC sources clustered into cell cycle- and autophagy-related pathways. Altogether, our studies provide a qualitative and quantitative comparative analysis of human erythropoiesis, highlighting the impact of the developmental origin of HSPCs on erythroid differentiation.

MeSH Terms

  • Adult
  • Aging
  • Antigens, CD34
  • Cells, Cultured
  • Colony-Forming Units Assay
  • Erythroid Precursor Cells
  • Erythropoiesis
  • Erythropoietin
  • Fetal Blood
  • Humans
  • Infant, Newborn
  • Transcriptome


Normal variation of bone marrow B-cell precursors according to age - reference ranges for studies in myelodysplastic syndromes in Brazil.

Normal B lymphoid maturation occurs in bone marrow (BM) throughout life, but immature B-cell progenitors (BCPs) are more numerous in children than in adults. To assess the normal values according to age became important as BCPs are decreased in myelodysplastic syndromes and have been considered an important diagnostic and prognostic feature in these clonal disorders. in a multicenter retrospective study from the Brazilian Group of Flow Cytometry we analyzed the variation of BCPs in normal BM according to age and technical peculiarities of each laboratory. We analysed of 45 BM donors and 89 cases examined for elucidation of transitory reactive cytopenias presenting a normal BM immunophenotyping. BCPs were enumerated as CD19 /CD34 /CD45 /CD10 cells (panel 1) or CD19 /CD34 /CD45 cells (panel 2) among the total nucleated non-erythroid cells and as percentage of CD34 cells. we included 134 cases. Panel 1 was applied in 88 cases and panel 2 was used in 46. Age range: 10 months to 89 years. In a multiple regression, % BCPs/total nucleated cells was an exponential function of age. Age explained alone 49.4% of the variance, while 'panel used' explained 1.8% and 'laboratory' explained 0.7%. Age explained only 24.9% of the variance of BCPs/CD34 cells. in normal individuals, BM B-cell precursors varied mainly according to age, but were also dependent on technical peculiarities of operators and equipments. Analysis by phenotype and as percentage of total nucleated cells was more accurate and less susceptible to variation than evaluating % BCPs/total CD34 cells. © 2017 International Clinical Cytometry Society.

MeSH Terms

  • Adolescent
  • Adult
  • Age Factors
  • Aged
  • Aged, 80 and over
  • Aging
  • Brazil
  • Child
  • Child, Preschool
  • Flow Cytometry
  • Humans
  • Infant
  • Middle Aged
  • Myelodysplastic Syndromes
  • Precursor Cells, B-Lymphoid
  • Reference Values
  • Retrospective Studies
  • Young Adult

Keywords

  • age variation
  • bone marrow
  • cytometry
  • hematogones


Aging process, adherence to Mediterranean diet and nutritional status in a large cohort of nonagenarians: Effects on endothelial progenitor cells.

Adherence to the Mediterranean Diet (MD) has been associated with a longer and better life. The aim of this study was to examine the effects of adherence to the MD, and of nutritional habits on endothelial progenitor (EPCs) and circulating progenitor (CPCs) cells in a cohort of nonagenarians enrolled within the Mugello Study, an epidemiological study aimed at investigating both clinically relevant geriatric items and various health issues, including those related to nutritional status. Four hundred twenty-one nonagenarians (306 F, 115 M, mean age: 93.1 ± 3.2 years) were evaluated. Adherence to MD was assessed through the Mediterranean Diet Score. Elderly subjects who were in the fourth quartile of the Mediterranean diet score showed significantly higher EPCs than subjects grouped into the other three quartiles. After adjustment for confounders, elderly subjects who were in the highest quartile of adherence to the MD score reported to have EPCs' levels significantly higher than those who reported lower values of adherence to the MD. Furthermore, by analyzing different food categories, it was reported that daily consumption of olive oil and a higher consumption of fruit and vegetables showed higher CPCs CD34 and EPCs CD34 /KDR than subjects with not daily or lower consumption. Our results support the hypothesis that the adherence to MD, as well as a daily consumption of olive oil and fruit and vegetables, characteristics of MD, may protect against the development of endothelial dysfunction through increasing EPCs and CPCs in older age.

MeSH Terms

  • Age Factors
  • Aged, 80 and over
  • Antigens, CD34
  • Biomarkers
  • Diet Surveys
  • Diet, Healthy
  • Diet, Mediterranean
  • Endothelial Progenitor Cells
  • Feeding Behavior
  • Female
  • Fruit
  • Geriatric Assessment
  • Healthy Aging
  • Humans
  • Italy
  • Male
  • Nutrition Assessment
  • Nutritional Status
  • Nutritive Value
  • Olive Oil
  • Protective Factors
  • Recommended Dietary Allowances
  • Risk Reduction Behavior
  • Vascular Endothelial Growth Factor Receptor-2
  • Vegetables

Keywords

  • Aging
  • Endothelial progenitor cells
  • Mediterranean diet
  • Nonagenarians

{{medline-entry |title=Lower resting and exercise-induced circulating angiogenic progenitors and angiogenic T cells in older men. |pubmed-url=https://pubmed.ncbi.nlm.nih.gov/29167123 |abstract=Aging is associated with a dysfunctional endothelial phenotype as well as reduced angiogenic capabilities. Exercise exerts beneficial effects on the cardiovascular system, possibly by increasing/maintaining the number and/or function of circulating angiogenic cells (CACs), which are known to decline with age. However, the relationship between cardiorespiratory fitness (CRF) and age-related changes in the frequency of CACs, as well as the exercise-induced responsiveness of CACs in older individuals, has not yet been determined. One-hundred seven healthy male volunteers, aged 18-75 yr, participated in study 1. CRF was estimated using a submaximal cycling ergometer test. Circulating endothelial progenitor cells (EPCs), angiogenic T cells (T ), and their chemokine (C-X-C motif) receptor 4 (CXCR4) cell surface receptor expression were enumerated by flow cytometry using peripheral blood samples obtained under resting conditions before the exercise test. In study 2, 17 healthy men (8 young men, 18-25 yr; 9 older men, 60-75 yr) were recruited, and these participants undertook a 30-min cycling exercise bout at 70% maximal O consumption, with CACs enumerated before and immediately after exercise. Age was inversely associated with both CD34 progenitor cells ( r  = -0.140, P = 0.000) and T ( r  = -0.176, P = 0.000) cells as well as CXCR4-expressing CACs (CD34 : r  = -0.167, P = 0.000; EPCs: r  = -0.098, P = 0.001; T : r  = -0.053, P = 0.015). However, after correcting for age, CRF had no relationship with either CAC subset. In addition, older individuals displayed attenuated exercise-induced increases in CD34 progenitor cells, T , CD4 , T , and CD8 CXCR4 T cells. Older men display lower CAC levels, which may contribute to increased risk of cardiovascular disease, and older adults display an impaired exercise-induced responsiveness of these cells. NEW