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1.
J Neurophysiol ; 132(2): 531-543, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38985935

RESUMO

Structural neuroplasticity such as neurite extension and dendritic spine dynamics is enhanced by brain-derived neurotrophic factor (BDNF) and impaired by types of inhibitory molecules that induce growth cone collapse and actin depolymerization, for example, myelin-associated inhibitors, chondroitin sulfate proteoglycans, and negative guidance molecules. These inhibitory molecules can activate RhoA/rho-associated coiled-coil containing protein kinase (ROCK) signaling (known to restrict structural plasticity). Intermittent hypoxia (IH) and high-intensity interval training (HIIT) are known to upregulate BDNF that is associated with improvements in learning and memory and greater functional recovery following neural insults. We investigated whether the RhoA/ROCK signaling pathway is also modulated by IH and HIIT in the hippocampus, cortex, and lumbar spinal cord of male Wistar rats. The gene expression of 25 RhoA/ROCK signaling pathway components was determined following IH, HIIT, or IH combined with HIIT (30 min/day, 5 days/wk, 6 wk). IH included 10 3-min bouts that alternated between hypoxia (15% O2) and normoxia. HIIT included 10 3-min bouts alternating between treadmill speeds of 50 cm·s-1 and 15 cm·s-1. In the hippocampus, IH and HIIT significantly downregulated Acan and NgR2 mRNA that are involved in the inhibition of neuroplasticity. However, IH and IH + HIIT significantly upregulated Lingo-1 and NgR3 in the cortex. This is the first time IH and HIIT have been linked to the modulation of plasticity-inhibiting pathways. These results provide a fundamental step toward elucidating the interplay between the neurotrophic and inhibitory mechanisms involved in experience-driven neural plasticity that will aid in optimizing physiological interventions for the treatment of cognitive decline or neurorehabilitation.NEW & NOTEWORTHY Intermittent hypoxia (IH) and high-intensity interval training (HIIT) enhance neuroplasticity and upregulate neurotrophic factors in the central nervous system (CNS). We provide evidence that IH and IH + HIIT also have the capacity to regulate genes involved in the RhoA/ROCK signaling pathway that is known to restrict structural plasticity in the CNS. This provides a new mechanistic insight into how these interventions may enhance hippocampal-related plasticity and facilitate learning, memory, and neuroregeneration.


Assuntos
Treinamento Intervalado de Alta Intensidade , Hipocampo , Ratos Wistar , Transdução de Sinais , Quinases Associadas a rho , Animais , Masculino , Quinases Associadas a rho/metabolismo , Quinases Associadas a rho/genética , Hipocampo/metabolismo , Transdução de Sinais/fisiologia , Ratos , Hipóxia/metabolismo , Hipóxia/fisiopatologia , Córtex Cerebral/metabolismo , Córtex Cerebral/fisiologia , Plasticidade Neuronal/fisiologia , Proteína rhoA de Ligação ao GTP/metabolismo , Medula Espinal/metabolismo , Medula Espinal/fisiologia , Proteínas rho de Ligação ao GTP
2.
Scand J Med Sci Sports ; 33(6): 882-893, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36785894

RESUMO

INTRODUCTION: Menopause is associated with vascular dysfunction and increased risk of developing metabolic syndrome. Associations between vascular and metabolic health, and interactions with aerobic exercise training, are unknown in postmenopausal women (PMW). METHODS: In habitually aerobically trained PMW (PMWtr; n = 10; 57 ± 1 years; 40 ± 1 mL/kg/min), strain-gauge plethysmography was used to compare resting and peak calf blood flow (CBFr and CBFpk, respectively) and vascular resistance (CVRr; CVRpk) versus untrained PMW (PMWun; n = 13; 56 ± 1 years; 29 ± 1 mL/kg/min) and premenopausal women (PreM; n = 14; 26 ± 1 years; 40 ± 1 mL/kg/min). Vascular measures were taken before and 1 hour after 45 minutes of aerobic exercise (60% V̇ O2peak ), a known nitric oxide stimulus. Blood analyses included low- (LDLc) and high-density lipoprotein cholesterol (HDLc), insulin, and glucose. RESULTS: Pre-exercise, CBFr and CVRr did not differ (p > 0.05) between PMW groups, nor between PreM and PMWtr. CBFpk was highest (p < 0.05) and CVRpk was lowest (p < 0.05) in PMWtr. Blood markers were similar (p > 0.05) in PMW groups. However, in PMWtr, CBFpk was associated inversely (p < 0.05) with insulin (r = -0.725). Conversely, in PMWun, CBFpk correlated (p < 0.05) inversely with glucose (r = -0.717), positively with HDLc (r = 0.633), and CVRpk positively (p < 0.05) with LDLc (r = 0.568). Post-exercise, CBF increased and CVR decreased (p < 0.05) in all groups, yet CBFpk remained higher and CVRpk lower (p < 0.05) in PMWtr. CONCLUSION: In untrained PMW, peak CBF is associated inversely with circulating pro-atherogenic lipids and glucose. In contrast, peak CBF is associated inversely with insulin levels only in trained PMW. Habitual aerobic exercise may favorably modulate vasculo-metabolic interactions in PMW.


Assuntos
Pletismografia , Pós-Menopausa , Humanos , Feminino , Pós-Menopausa/fisiologia , Insulina , HDL-Colesterol , Glucose
3.
J Aging Phys Act ; 30(3): 510-516, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34564066

RESUMO

It is unclear how running modality influences telomere length (TL). This single laboratory visit study compared the TL of master sprinters and endurance runners with their young counterparts. The correlation between leukocyte and buccal cell TL in athletes was also explored. Participants consisted of 11 young controls, 11 young sprinters, 12 young endurance runners, 12 middle-aged controls, 11 master sprinters, and 12 master endurance runners. Blood and buccal samples were collected and randomized for analysis of TL by quantitative polymerase chain reaction. Young endurance runners displayed longer telomeres than master athletes (p < .05); however, these differences were not significant when controlled for covariates (p > .05). A positive correlation existed between leukocyte and buccal cell TL in athletes (r = .567, p < .001). In conclusion, young endurance runners possess longer telomeres than master endurance runners and sprinters, a consequence of lower body mass index and visceral fat.


Assuntos
Corrida , Atletas , Humanos , Pessoa de Meia-Idade , Estado Nutricional , Resistência Física/genética , Telômero
4.
Am J Physiol Cell Physiol ; 320(3): C253-C263, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33356943

RESUMO

Breast cancer is the most prevalent cancer in women worldwide. In the United Kingdom, approximately 5% of all breast cancers are already metastatic at the time of diagnosis. An abundance of literature shows that exercise can have beneficial effects on the outcome and prognosis of breast cancer patients, yet the molecular mechanisms remain poorly understood. There are several in vitro models that aim to recapitulate the response of breast cancer to exercise in vivo; this systematic review and meta-analysis summarizes the existing literature. The following search terms were used to conduct a systematic literature search using a collection of databases (last search performed May 2020): "in vitro," "exercise," and "breast cancer." Only studies that investigated the effects of exercise on breast cancer in vitro were included. Standardized mean differences (SMD) were calculated to determine pooled effect sizes. This meta-analysis has successfully demonstrated that various identified exercise interventions on breast cancer cells in vitro significantly reduced breast cancer cell viability, proliferation, and tumorigenic potential (SMD = -1.76, P = 0.004, SMD = -2.85, P = 0.003, and SMD = -3.15, P = 0.0008, respectively). A clear direction of effect was found with exercise on breast cancer cell migration in vitro, however this effect was not significant (SMD = -0.62, P = 0.317). To our knowledge, this is the first meta-analysis and systematic review investigating and summarizing literature on exercise and breast cancer in vitro, highlighting models used and priority areas for future research focus.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/fisiopatologia , Exercício Físico/fisiologia , Animais , Mama/patologia , Mama/fisiopatologia , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Progressão da Doença , Feminino , Humanos
5.
J Transl Med ; 17(1): 397, 2019 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-31783866

RESUMO

Mesenchymal stem cells (MSCs) represent an invaluable asset for the field of cell therapy. Human Bone marrow-derived MSCs (hBM-MSCs) are one of the most commonly used cell types in clinical trials. They are currently being studied and tested for the treatment of a wide range of diseases and conditions. The future availability of MSCs therapies to the public will require a robust and reliable delivery process. Cryopreservation represents the gold standard in cell storage and transportation, but its effect on BM-MSCs is still not well established. A systematic review was conducted to evaluate the impact of cryopreservation on BM-MSCs and to attempt to uncover the reasons behind some of the controversial results reported in the literature. Forty-one in vitro studies were analysed, and their results organised according to the cell attributes they assess. It was concluded that cryopreservation does not affect BM-MSCs morphology, surface marker expression, differentiation or proliferation potential. However, mixed results exist regarding the effect on colony forming ability and the effects on viability, attachment and migration, genomic stability and paracrine function are undefined mainly due to the huge variabilities governing the cryopreservation process as a whole and to the lack of standardised assays.


Assuntos
Criopreservação , Células-Tronco Mesenquimais/citologia , Animais , Apoptose , Diferenciação Celular , Proliferação de Células , Forma Celular , Sobrevivência Celular , Senescência Celular , Congelamento , Humanos , Imunofenotipagem , Células-Tronco Mesenquimais/metabolismo , Especificidade da Espécie
6.
Ann Hum Biol ; 46(5): 430-433, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31448632

RESUMO

In this study, VDR gene ApaI (rs7975232), BsmI (rs 1544410) and TaqI (rs731236) genotypes were compared in men with osteoporosis and male controls. Osteoporosis affects around 20% of all men and overall mortality in the first year after hip fracture is significantly higher in men than women, yet the genetic basis of osteoporosis is less well studied in males. This study consisted of White British males; 69 osteoporosis patients and 122 controls. BMDs at the lumbar spine (vertebrae L1-L4) and hip (femur neck) were measured by dual-energy X-ray absorptiometry (DEXA). The VDR gene ApaI, BsmI and TaqI genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and association analysis was carried out at genotype and haplotype level. Our study suggests that TaqI polymorphism CC genotype frequency is lower in controls and further analysis of genotypes and BMD revealed a significant effect of TaqI polymorphism on Lumbar spine BMD. Two haplotypes (GCC and AAT) were associated with increased osteoporosis risk. In conclusion, VDR gene TaqI polymorphism in recessive mode had a significant effect on lumbar spine BMD within our study. Haplotypes GCC and AAT increase the risk of osteoporosis among White British males.


Assuntos
Densidade Óssea/genética , Osteoporose/genética , Polimorfismo Genético , Receptores de Calcitriol/genética , Absorciometria de Fóton , Idoso , Estudos de Casos e Controles , Colo do Fêmur/fisiologia , Genótipo , Haplótipos , Humanos , Vértebras Lombares/fisiologia , Masculino , Pessoa de Meia-Idade , Osteoporose/epidemiologia , Fatores de Risco , Reino Unido/epidemiologia
7.
J Cell Biochem ; 119(7): 5686-5695, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29384221

RESUMO

Skeletal muscle is an insulin sensitive tissue and accounts for approximately 80% of post-prandial glucose disposal. This study describes the effects of insulin, delivered for 72 h, to skeletal muscle myoblasts during differentiation or to skeletal muscle myotubes. After chronic treatment, cultures were acutely stimulated with insulin and analyzed for total and phosphorylated Akt (Ser473 ), mRNA expression of metabolic and myogenic markers and insulin-stimulated glucose uptake. Skeletal muscle cells differentiated in the presence of insulin chronically, reduced acute insulin stimulated phosphorylation of Akt Ser473 . In addition, there was a reduction in mRNA expression of Hexokinase II (HKII), GLUT4 and PGC-1α. Insulin-stimulated glucose uptake was attenuated when cells were differentiated in the presence of insulin. In contrast, myotubes exposed to chronic insulin showed no alterations in phosphorylation of Akt Ser473 . Both HKII and GLUT4 mRNA expression were reduced by chronic exposure to insulin; while PGC-1α was not different between culture conditions and was increased by acute insulin stimulation. These data suggest that there are differential responses in insulin signalling, transcription, and glucose uptake of skeletal muscle cells when cultured in either the presence of insulin during differentiation or in myotube cultures.


Assuntos
Biomarcadores/metabolismo , Diferenciação Celular/efeitos dos fármacos , Glucose/metabolismo , Insulina/farmacologia , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Mioblastos/metabolismo , Animais , Células Cultivadas , Transportador de Glucose Tipo 4/metabolismo , Hipoglicemiantes/farmacologia , Resistência à Insulina , Camundongos , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/efeitos dos fármacos , Músculo Esquelético/citologia , Músculo Esquelético/efeitos dos fármacos , Mioblastos/citologia , Mioblastos/efeitos dos fármacos , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo
8.
Ann Hum Genet ; 81(4): 141-146, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28620993

RESUMO

This study investigated the role of IL-1ß-511 (rs16944), TLR4-896 (rs4986790) and TNF-α-308 (rs1800629) polymorphisms in type 2 diabetes mellitus (T2DM) among an endogamous Northern Indian population. Four hundred fourteen participants (204 T2DM patients and 210 nondiabetic controls) were genotyped for IL-1ß-511, TLR4-896 and TNF-α-308 loci. The C allele of IL-1ß-511 was shown to increase T2DM susceptibility by 75% (OR: 1.75 [CI 1.32-2.33]). Having two parents affected by T2DM increased susceptibility by 5.7 times (OR: 5.693 [CI 1.431-22.648]). In this study, we have demonstrated a conclusive association with IL-1ß-511 locus and IL-1ß-511-TLR4-896 diplotype (CC-AA) and T2DM, which warrants further comprehensive analyses in larger cohorts.


Assuntos
Diabetes Mellitus Tipo 2/genética , Interleucina-1beta/genética , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/genética , Idoso , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Índia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético
9.
Am J Hum Biol ; 28(6): 941-944, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27292586

RESUMO

OBJECTIVES: Indian subpopulations (Chenchu, Koya, and Lobana Sikh) were analyzed at the genetic level for 12 Alu polymorphisms. These markers were then utilized to establish levels of genetic identity between the Indian populations and more widely between the Indian populations and a European population. METHODS: Previously collected blood samples were extracted using the phenol-chloroform method. The samples were utilized as templates for PCR using Alu specific primers and then analyzed by agarose gel electrophoresis for the presence and absence of the approximately 300 bp insertions. Allele frequencies were calculated by the gene counting method and were tested for Hardy-Weinberg equilibrium, heterozygosities, inbreeding coefficient, and GST to assess the level of genetic differentiation. RESULTS: All of the Alu loci were polymorphic in the three Indian populations studied and their average observed heterozygosity ranged from 0.294 (Lobana Sikh) to 0.357 (Koya). Allele and genotype frequency variation at the 2b, 9a, and ACE loci led to statistically significant pairwise differences among the three study populations. Overall population heterogeneity was observed for 7 out of 12 Alu polymorphisms. CONCLUSION: The overall results show that these Indian samples, though displaying significant genetic variation and differences among themselves, form an Indian cluster, which as expected, is distinct from the European sample (Russian). As Alus are easily analyzed and quantified by standard and cost-effective methodologies, this finding further reinforces their utility as effective population genetic markers. Am. J. Hum. Biol., 2016. © 2016 Wiley Periodicals, Inc. Am. J. Hum. Biol. 28:941-944, 2016. © 2016Wiley Periodicals, Inc.


Assuntos
Elementos Alu/genética , Frequência do Gene , Variação Genética , Polimorfismo Genético/genética , Deriva Genética , Humanos , Índia
10.
Breast Cancer (Auckl) ; 17: 11782234221145385, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36710995

RESUMO

Purpose: Breast cancer is the most diagnosed cancer and the leading cause of cancer death in women globally, and mesenchymal stem cells have been widely implicated in tumour progression. This systematic review and meta-analysis seeks to identify and summarise existing literature on the effects of human mesenchymal stem cells (hMSCs) on the migration of breast cancer cells (BCCs) in vitro, to determine the direction of this relationship according to existing research and to identify the directions for future research. Methods: A systematic literature search was conducting using a collection of databases, using the following search terms: in vitro AND mesenchymal stem cells AND breast cancer. Only studies that investigated the effects of human, unmodified MSCs on the migration of human, unmodified BCCs in vitro were included. Standardised mean differences (SMDs) were calculated to determine pooled effect sizes. Results: This meta-analysis demonstrates that hMSCs (different sources combined) increase the migration of both MDA-MB-231 and MCF-7 cell lines in vitro (SMD = 1.84, P = .03 and SMD = 2.69, P < .00001, respectively). Importantly, the individual effects of hMSCs from different sources were also analysed and demonstrated that MSCs derived from human adipose tissue increase BCC migration (SMD = 1.34, P = .0002) and those derived from umbilical cord increased both MDA-MB-231 and MCF-7 migration (SMD = 3.93, P < .00001 and SMD = 3.01, P < .00001, respectively). Conclusions: To our knowledge, this is the first systematic review and meta-analysis investigating and summarising the effects of hMSCs from different sources on the migration of BCCs, in vitro.

11.
Biopreserv Biobank ; 21(5): 450-457, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36094454

RESUMO

Introduction: For stem cell therapies to be adopted in mainstream health care, robust, reliable, and cost-effective storage and transport processes must be developed. Cryopreservation remains the best current platform for this purpose, and freezing cells at high concentration may have many benefits, including savings on cost and storage space, facilitating transport logistics, and reducing cryoprotectant volume. Cells, such as mesenchymal stem cells (MSCs), are typically frozen at 1 million cells per milliliter (mL), but the aim of this study is to examine the post-thaw attributes of human bone marrow derived MSCs (hBM-MSCs) frozen at 1, 5, and 10 million cells per mL. Methods: Thawed cells were assessed for their morphology, phenotypic marker expression, viability, apoptosis level, metabolic activity, proliferation, and osteogenic and adipogenic differentiation. Results: In this study, for the first time, it is shown that all assessed cells expressed the typical MSC markers (CD90, CD105, and CD73) and lacked the expression of CD14, CD20, CD34, CD45, and HLA-DR. In addition, all cells showed elongated fibroblastic morphology. Post-thaw viability was retained with no difference among the three concentrations. Moreover, no significant statistical difference was observed in the post-thaw apoptosis level, metabolic activity, proliferation, and osteogenic potential, indicating that these cells are amenable to cryopreservation at higher concentrations. Conclusion: The results of this study are of paramount importance to the development of manufacturing processes around a useful freezing concentration when cells are targeted to be stored for at least 6 months.

12.
J Bodyw Mov Ther ; 30: 118-124, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35500959

RESUMO

Telomeres are dynamic structures that appear to be positively influenced by healthy lifestyle factors such as exercise. Pilates is an increasingly popular exercise modality that is reported to exert beneficial physiological effects in the body, although the cellular mechanisms are poorly understood. The aim of the present study was to investigate the influence of Pilates exercise on telomere length. This longitudinal study followed experienced female Pilates practitioners (n = 11, 50.8 ± 7.5 years) and healthy age- and sex-matched sedentary controls (n = 11, 49.3 ± 6.1 years) over a 12-month period. Leukocyte telomere length was quantified using qPCR. Circulatory inflammatory markers, mRNA gene expression, body composition, physical performance, and mental well-being were also assessed. Telomere length was comparable between Pilates practitioners and controls at baseline (Pre) and 12-months (Post) (p > 0.0125). Pilates practitioners displayed enhanced mRNA gene expression of antioxidant enzymes (SOD2 and GPX1), and lower body fat percentage and visceral fat rating, compared with sedentary controls (p < 0.0125). Over the 12-month longitudinal period, Pilates participants significantly increased dynamic balance (p < 0.05). In conclusion, long-term Pilates participation does not appear to influence telomere length. Nonetheless, Pilates exercise appears to increase antioxidant enzyme gene expression, effectively manage body composition, and improve dynamic balance.


Assuntos
Antioxidantes , Composição Corporal , Composição Corporal/fisiologia , Feminino , Humanos , Estudos Longitudinais , RNA Mensageiro , Telômero
13.
Sci Rep ; 12(1): 3504, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35241723

RESUMO

Breast cancer is a persisting global burden for health services with cases and deaths projected to rise in future years. Surgery complemented by adjuvant therapy is commonly used to treat breast cancer, however comes with detrimental side effects to physical fitness and mental wellbeing. The aim of this systematic review and meta-analysis is to determine whether resistance and endurance interventions performed during adjuvant treatment can lastingly ameliorate these side effects. A systematic literature search was performed in various electronic databases. Papers were assessed for bias and grouped based on intervention design. RStudio was used to perform the meta-analyses for each group using the 'meta' package. Publication bias and power analyses were also conducted. These methods conform to PRISMA guidelines. Combined resistance and endurance interventions elicited significant long-lasting improvements in global fatigue and were beneficial to the remaining side effects. Individually, resistance and endurance interventions non-significantly improved these side effects. Resistance interventions elicited higher benefits overall. Exercise interventions have lasting clinical benefits in ameliorating adjuvant therapy side effects, which negatively impact physical fitness and mental wellbeing. These interventions are of clinical value to enhance adherence rates and avoid comorbidities such as sarcopenia, thus improving disease prognosis.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/terapia , Terapia por Exercício , Fadiga/terapia , Feminino , Humanos , Resistência Física , Aptidão Física , Prognóstico , Qualidade de Vida
14.
Bioorg Med Chem Lett ; 21(12): 3616-21, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21592791

RESUMO

A novel series of biaryl phenoxyacetic acids was discovered as potent, selective antagonists of the chemoattractant receptor-homologous expressed on Th2 lymphocytes receptor (CRTh2 or DP2). A hit compound 4 was discovered from high throughput screening. Modulation of multiple aryl substituents afforded both agonists and antagonists, with small changes often reversing the mode of action. Understanding the complex SAR allowed design of potent antagonists such as potential candidate 34.


Assuntos
Acetatos/síntese química , Receptores Imunológicos/agonistas , Receptores Imunológicos/antagonistas & inibidores , Receptores de Prostaglandina/agonistas , Receptores de Prostaglandina/antagonistas & inibidores , Acetatos/química , Acetatos/farmacologia , Animais , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Ratos , Relação Estrutura-Atividade
15.
Gene ; 769: 145242, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33068677

RESUMO

PURPOSE: Elite athletes are reported to possess longer telomeres than their less active counterparts. ACE gene (Insertion/Deletion) polymorphism has been previously associated with elite athletic performance, with the deletion (D) variant appearing more frequently in short distance swimmers. Additionally, the D allele has been reported to have a negative effect on telomere length. The aim of this study was to investigate the telomere length of elite swimmers and its potential association with ACE genotype. METHODS: Telomere length was measured by real-time quantitative PCR and ACE I/D genotypes analysed by standard PCR and electrophoresis in 51 young elite swimmers and 56 controls. RESULTS: Elite swimmers displayed shorter telomeres than controls (1.043 ± 0.127 vs 1.128 ± 0.177, p = 0.006). When split by sex, only elite female swimmers showed significantly shorter telomeres than their recreationally active counterparts (p = 0.019). ACE genotype distribution and allelic frequency did not differ between elite swimmers and controls, or by event distance among elite swimmers only. No association was observed between telomere length and ACE genotype in the whole cohort. CONCLUSIONS: Elite swimmers possessed shorter telomeres than recreationally active controls. Our findings suggesting a negative effect of high-level swimming competition and/or training on telomere length and subsequent biological aging, particularly in females. However, this significant difference in telomere length does not appear to be attributed to the D allele as we report a lack of association between telomere length and ACE genotype frequency in elite swimmers and controls.


Assuntos
Desempenho Atlético , Peptidil Dipeptidase A/genética , Natação , Telômero , Adolescente , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Mutação INDEL , Masculino , Adulto Jovem
16.
Stem Cell Res Ther ; 11(1): 540, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33317625

RESUMO

BACKGROUND: The effects of cryopreservation on human bone marrow-derived mesenchymal stem cells (hBM-MSCs) are still ill-defined. In this study, a quantitative approach was adopted to measure several post-thaw cell attributes in order to provide an accurate reflection of the freezing and thawing impact. METHODS: Fresh and cryopreserved passage-matched cells from three different donors were discretely analysed and compared for their viability, apoptosis level, phenotypic marker expression, metabolic activity, adhesion potential, proliferation rate, colony-forming unit ability (CFUF) and differentiation potentials. RESULTS: The results of this study show that cryopreservation reduces cell viability, increases apoptosis level and impairs hBM-MSC metabolic activity and adhesion potential in the first 4 h after thawing. At 24 h post-thaw, cell viability recovered, and apoptosis level dropped but metabolic activity and adhesion potential remained lower than fresh cells. This suggests that a 24-h period is not enough for a full recovery. Beyond 24 h post-thaw, the observed effects are variable for the three cell lines. While no difference is observed in the pre- and post-cryopreservation proliferation rate, cryopreservation reduced the CFUF ability of two of the cell lines and variably affected the adipogenic and osteogenic differentiation potentials of the three cell lines. CONCLUSION: The data collected in this study clearly show that fresh and cryopreserved hBM-MSCs are different, and these differences will inevitably introduce variabilities to the product and process development and subsequently imply financial losses. In order to avoid product divergence pre- and post-cryopreservation, effective strategies to mitigate freezing effects must be developed and implemented.


Assuntos
Células-Tronco Mesenquimais , Medula Óssea , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Criopreservação , Humanos , Osteogênese
17.
Heliyon ; 6(6): e04151, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32551387

RESUMO

Telomere dynamics are an active biological process and positive lifestyle factors such as exercise are proposed to potentiate their length. The aim of this study was to investigate the effect of a low-resistance, high-repetition resistance training intervention on leukocyte telomere length (LTL) and associated health parameters. 23 sedentary middle-aged adults volunteered for this study (16 female/7 male; age = 51.5 ± 4.9 years) and performed two one-hour sessions of Les Mills BODYPUMP™ per week for 12 weeks. Outcome measures were taken at baseline, after the training intervention and at 12-month follow-up. LTL remained unchanged following the training intervention (pre 0.819 ± 0.121 vs post 0.812 ± 0.114, p = 0.420), despite a borderline significant increase in hTERT expression (p = 0.050). Circulating levels of tumour necrosis factor alpha were reduced after the intervention (p = 0.001). At 12-month follow-up, subjects who returned to a sedentary lifestyle (n = 10) displayed shorter telomeres compared to their pre (p = 0.036) values. In conclusion, no changes were observed in LTL following the 12-week training intervention, despite improvements in molecular parameters associated with telomere dynamics. It appears continued long-term exercise (>12 months) is necessary to preserve LTL in previously sedentary individuals.

18.
J Mol Endocrinol ; 64(3): 125-132, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31990657

RESUMO

Hyperinsulinaemia potentially contributes to insulin resistance in metabolic tissues, such as skeletal muscle. The purpose of these experiments was to characterise glucose uptake, insulin signalling and relevant gene expression in primary human skeletal muscle-derived cells (HMDCs), in response to prolonged insulin exposure (PIE) as a model of hyperinsulinaemia-induced insulin resistance. Differentiated HMDCs from healthy human donors were cultured with or without insulin (100 nM) for 3 days followed by an acute insulin stimulation. HMDCs exposed to PIE were characterised by impaired insulin-stimulated glucose uptake, blunted IRS-1 phosphorylation (Tyr612) and Akt (Ser473) phosphorylation in response to an acute insulin stimulation. Glucose transporter 1 (GLUT1), but not GLUT4, mRNA and protein increased following PIE. The mRNA expression of metabolic (PDK4) and inflammatory markers (TNF-α) was reduced by PIE but did not change lipid (SREBP1 and CD36) or mitochondrial (UCP3) markers. These experiments provide further characterisation of the effects of PIE as a model of hyperinsulinaemia-induced insulin resistance in HMDCs.


Assuntos
Hiperinsulinismo/metabolismo , Resistência à Insulina , Insulina/farmacologia , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Adulto , Células Cultivadas , Glucose/metabolismo , Humanos , Hiperinsulinismo/patologia , Insulina/metabolismo , Masculino , Fibras Musculares Esqueléticas/patologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Transdução de Sinais/efeitos dos fármacos , Adulto Jovem
19.
Stem Cells Dev ; 27(19): 1303-1321, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30003826

RESUMO

Most cells in the human body, including human mesenchymal stem cells (hMSCs), have evolved to survive and function in a low physiological oxygen (O2) environment. Investigators have become increasingly aware of the effects of O2 levels on hMSC biology and culture and are mimicking the natural niche of these cells in vitro to improve cell culture yields. This presents many challenges in relation to hMSC identity and function and in the maintenance of a controlled O2 environment for cell culture. The aim of this review was to discuss an "hMSC checklist" as a guide to establishing which identity and potency assays to implement when studying hMSCs. The checklist includes markers, differentiation potential, proliferation and growth, attachment and migration, genomic stability, and paracrine activity. Evidence drawn from the current literature demonstrates that low O2 environments could improve most "hMSC checklist" attributes. However, there are substantial inconsistencies around both the terminology and the equipment used in low O2 studies. Therefore, "hypoxia" as a term and as a culture condition is discussed. The biology of short-term (acute) versus long-term (chronic) hypoxia is considered, and a nascent hypothesis to explain the behavior of hMSCs in long-term hypoxia is presented. It is hoped that by establishing an ongoing discourse and driving toward a regulatory recognizable "hMSC checklist," we may be better able to provide the patient population with safe and efficacious regenerative treatments.


Assuntos
Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Oxigênio/metabolismo , Cultura Primária de Células/métodos , Hipóxia Celular , Meios de Cultura/química , Humanos , Células-Tronco Mesenquimais/citologia , Oxigênio/análise
20.
Gene ; 628: 301-307, 2017 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-28739396

RESUMO

BACKGROUND: Cytokines regulate the expression of inflammatory molecules which destabilize the atheromatic plaques. This study focuses on studying the association of inflammatory cytokine polymorphisms like TNF-α -308 (G/A), TNF-ß +252 (A/G), IL-6 -174 (G/C) and IL-6 -597 (G/A), and IFN-É£ +874 (T/A) with coronary artery disease (CAD) among north Indian patients. MATERIALS AND METHODS: 143 CAD and 137 normal healthy controls were recruited in this study. DNA extraction was carried out by high salting out method. TNF-α -308 (G/A) (rs1800797), TNF-ß +252 (A/G) (rs909253), IL-6 -174 (G/C) (rs1800795), IL6 -597 (G/A) (rs1800797), and IFN-É£ +874 (T/A) (rs2430561) SNPs were genotyped by TaqMan®SNP genotyping assays. Different statistical analyses were performed using SPSS v 22.0 and SNPStats. p≤0.05 was considered significant. RESULTS: Significant risk association with CAD was found for TNF-α -308 (G/A) "A" allele (OR=5.6, CI 1.8-17.4, p=0.001) and TNF-ß +252 (A/G) "G" allele (OR=3.4, CI=1.9-6.0, p<0.001). However, no statistical significance was found for IL-6 -174 (G/C) or IL6 -597 (G/A), with CAD. TNF-α -308 (G/A), and TNF-ß +252 (A/G) haplotype "GG" "AG" increased CAD risk significantly (GG haplotype, adjusted OR=2.6, CI 1.4-5.0, p=0.003 and AG haplotype OR=8.5, CI 2.2-33.35, p=0.002) after adjustments for age, sex, TC, TG, HDL, APOB, smoking and diet. DISCUSSION: The present study found significant risk association for TNF-α -308 (G/A), and TNF-ß +252 (A/G) genotypes, alleles and haplotypes, with CAD in a North Indian population.


Assuntos
Doença da Artéria Coronariana/genética , Citocinas/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Análise de Variância , Biomarcadores , Estudos de Casos e Controles , Doença da Artéria Coronariana/sangue , Feminino , Frequência do Gene , Genótipo , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco
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