RESUMO
Senescent cells have been linked to the pathogenesis of metabolic dysfunction-associated steatotic liver disease (MASLD). However, the effectiveness of senolytic drugs in reducing liver damage in mice with MASLD is not clear. Additionally, MASLD has been reported to adversely affect male reproductive function. Therefore, this study aimed to evaluate the protective effect of senolytic drugs on liver damage and fertility in male mice with MASLD. Three-month-old male mice were fed a standard diet (SD) or a choline-deficient western diet (WD) until 9 months of age. At 6 months of age mice were randomized within dietary treatment groups into senolytic (dasatinib + quercetin [D + Q]; fisetin [FIS]) or vehicle control treatment groups. We found that mice fed choline-deficient WD had liver damage characteristic of MASLD, with increased liver size, triglycerides accumulation, fibrosis, along increased liver cellular senescence and liver and systemic inflammation. Senolytics were not able to reduce liver damage, senescence and systemic inflammation, suggesting limited efficacy in controlling WD-induced liver damage. Sperm quality and fertility remained unchanged in mice developing MASLD or receiving senolytics. Our data suggest that liver damage and senescence in mice developing MASLD is not reversible by the use of senolytics. Additionally, neither MASLD nor senolytics affected fertility in male mice.
Assuntos
Fertilidade , Flavonóis , Quercetina , Senoterapia , Animais , Masculino , Camundongos , Fertilidade/efeitos dos fármacos , Quercetina/farmacologia , Senoterapia/farmacologia , Flavonóis/farmacologia , Fígado/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Senescência Celular/efeitos dos fármacos , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Dieta Ocidental/efeitos adversos , Progressão da Doença , Deficiência de Colina/complicações , Camundongos Endogâmicos C57BL , Modelos Animais de DoençasRESUMO
PURPOSE: The separation between the inside and outside through the skin was fundamental for the evolution of prevertebrates, which grow through extrapituitary circuits, to vertebrates, which grow through the somatotrophic axis, namely pituitary growth hormone (GH). and circulating IGF1.Individuals with untreated isolated growth hormone (GH) deficiency (IGHD) due to a mutation in the GH-releasing hormone receptor (GHRH) gene, residing in Itabaianinha, Brazil, are vulnerable to skin cancer and have reduced sweating. However other aspects of their skin physiology are still unknown. Our objectives were to evaluate the number of skin cancers, skin aging, and functional aspects of the skin in this IGHD cohort. METHODS: Twenty-six IGHD individuals and 26 controls matched by age, sex, ethnicity, and occupation were submitted to a biochemical, dermatological and a functional skin assessment by the Multi Probe Adapter Cutometer® MPA 580. RESULTS: There was no difference in the number of skin cancers and in the degrees of photodamage between the groups. The melanin content in the forearm was similar between the groups but was lower in the buttocks (p = 0.005), as well as skin resistance (p < 0.0001) and elasticity (p = 0.003), lower in the IGHD. There was no difference in hydration and sebum content between the two groups. CONCLUSION: IGHD is apparently associated with a neutral profile in terms of skin cancer and photodamage, with similar melanin on the forearm and lower buttocks, lower skin resistance and elasticity, with hydration and sebum similar to controls.
Assuntos
Hormônio do Crescimento Humano , Pele , Humanos , Masculino , Feminino , Adulto , Pele/metabolismo , Hormônio do Crescimento Humano/deficiência , Pessoa de Meia-Idade , Neoplasias Cutâneas , Envelhecimento da Pele/fisiologia , Adulto Jovem , Fenômenos Fisiológicos da Pele , Nanismo Hipofisário/epidemiologia , AdolescenteRESUMO
PURPOSE: Considering that the combination of dasatinib and quercetin (D + Q) demonstrated a neuroprotective action, as well as that females experience a decline in hormonal levels during aging and this is linked to increased susceptibility to Alzheimer's disease, in this study we evaluated the effect of D + Q on inflammatory and oxidative stress markers and on acetylcholinesterase and Na+, K+-ATPase activities in brain of female mice. METHODS: Female C57BL/6 mice were divided in Control and D (5 mg/kg) + Q (50 mg/kg) treated. Treatment was administered via gavage for three consecutive days every two weeks starting at 30 days of age. The animals were euthanized at 6 months of age and at 14 months of age. RESULTS: Results indicate an increase in reactive species (RS), thiol content and lipid peroxidation followed by a reduction in nitrite levels and superoxide dismutase, catalase and glutathione S-transferase activity in the brain of control animals with age. D+Q protected against age-associated increase in RS and catalase activity reduction. Acetylcholinesterase activity was increased, while Na+, K+-ATPase activity was reduced at 14 months of age and D+Q prevented this reduction. CONCLUSION: These data demonstrate that D+Q can protect against age-associated neurochemical alterations in the female brain.
Assuntos
Acetilcolinesterase , Senoterapia , Ratos , Feminino , Camundongos , Animais , Catalase/metabolismo , Acetilcolinesterase/metabolismo , Ratos Wistar , Camundongos Endogâmicos C57BL , Antioxidantes/farmacologia , Estresse Oxidativo , Quercetina/farmacologia , Encéfalo/metabolismo , Superóxido Dismutase/metabolismo , Adenosina TrifosfatasesRESUMO
Senescent cell number increases with age in different tissues, leading to greater senescent cell load, proinflammatory stress, and tissue dysfunction. In the current study, we tested the efficacy of senolytic drugs to reduce ovarian senescence and improve fertility in reproductive age female mice. In the first experiment, 1-month-old C57BL/6 female mice were treated every other week with D + Q (n = 24) or placebo (n = 24). At 3 and 6 months of age, female mice were mated with untreated males to evaluate pregnancy rate and litter size. In the second experiment, 6-month-old C57BL/6 female mice were treated monthly with D + Q (n = 30), fisetin (n = 30), or placebo (n = 30). Females were treated once a month until 11 months of age, then they were mated with untreated males for 30 days to evaluate pregnancy rate and litter size. In the first experiment, D + Q treatment did not affect pregnancy rate (P = 0.68), litter size (P = 0.58), or ovarian reserve (P > 0.05). Lipofuscin staining was lower in females treated with D + Q (P = 0.04), but expression of senescence genes in ovaries was similar. In the second experiment, D + Q or fisetin treatment also did not affect pregnancy rate (P = 0.37), litter size (P = 0.20), or ovarian reserve (P > 0.05). Lipofuscin staining (P = 0.008) and macrophage infiltration (P = 0.002) was lower in fisetin treated females. Overall, treatment with D + Q or fisetin did not affect ovarian reserve or fertility but did decrease some senescence markers in the ovary.
Assuntos
Reserva Ovariana , Gravidez , Masculino , Camundongos , Feminino , Animais , Senoterapia , Lipofuscina , Camundongos Endogâmicos C57BL , FertilidadeRESUMO
Calorie restriction (CR) is an intervention that promotes longevity and preserves the ovarian reserve. Some studies have observed that the positive impacts of CR can be linked to restriction of protein (PR) and branched-chain amino acids (BCAAs) independent of calorie intake. The aim of this study was to compare the effects of protein and BCAA restriction to 30% CR on the ovarian reserve of female mice. For this, 3 month-old C57BL/6 female mice (n = 35) were randomized into four groups for four months dietary interventions including: control group (CTL; n = 8), 30% CR (CR; n = 9), protein restriction (PR; n = 9) and BCAA restriction (BCAAR; n = 9). Body mass gain, body composition, food intake, serum levels of BCAAs, ovarian reserve and estrous cyclicity were evaluated. We observed that CR, protein and BCAA restriction prevented weight gain and changed body composition compared to the CTL group. The BCAA restriction did not affect the ovarian reserve, while both PR and CR prevented activation of primordial follicles. This prevention occurred in PR group despite the lack of reduction of calorie intake compared to CTL group, and CR did not reduce protein intake in levels similar to the PR group. BCAA restriction resulted in increased calorie intake compared to CTL and PR mice, but only PR reduced serum BCAA levels compared to the CTL group. Our data indicates that PR has similar effects to CR on the ovarian reserve, whereas BCAA restriction alone did not affect it.
Assuntos
Restrição Calórica , Ingestão de Energia , Camundongos , Feminino , Animais , Camundongos Endogâmicos C57BL , Envelhecimento , Aminoácidos de Cadeia Ramificada/metabolismoRESUMO
In females, there is a continuous decline of the ovarian reserve with age, which results in menopause in women or estropause in mice. Loss of ovarian function results in metabolic alterations in mice and women. Based on this, we aimed to evaluate the effect of caloric restriction (CR) on redox status and metabolic changes in chemically induced estropause in mice. For this, mice were divided into four groups (n = 10): cyclic ad libitum (AL), cyclic 30% CR, AL estropause, and estropause 30% CR. Estropause was induced using 4-vinylcyclohexene diepoxide (VCD) for 20 consecutive days in 2-month-old females. The CR protocol started at 5 months of age and the treatments lasted for 4 months. The CR females gained less body weight than AL females (p < 0.001) and had lower glycemic curves in response to glucose tolerance test (GTT). The AL estropause females had the highest body weight and body fat, despite having lower food intake. However, the estropause females on 30% CR lost the most body weight and had the lowest amount of body fat compared to all groups. The effect of 30% CR on redox status in fat and liver tissue was similar for cyclic and estropause females. Interestingly, estropause decreased ROS in adipose tissue, while increasing it in the liver. No significant effects of CR on redox status were observed. Chemically induced estropause did not influence the response to 30% CR on glucose tolerance and redox status; however, weight loss was exarcebated compared to cyclic females.
Assuntos
Restrição Calórica , Redução de Peso , Humanos , Camundongos , Feminino , Animais , Peso Corporal , Tecido Adiposo , OxirreduçãoRESUMO
Cellular senescence is a defense mechanism to arrest proliferation of damaged cells. The number of senescent cells increases with age in different tissues and contributes to the development of age-related diseases. Old mice treated with senolytics drugs, dasatinib and quercetin (D+Q), have reduced senescent cells burden. The aim of this study was to evaluate the effects of D+Q on testicular function and fertility of male mice. Mice (n = 9/group) received D (5 mg kg-1) and Q (50 mg kg-1) via gavage every moth for three consecutive days from 3 to 8 months of age. At 8 months mice were breed with young non-treated females and euthanized. The treatment of male mice with D+Q increased serum testosterone levels and sperm concentration and decreased abnormal sperm morphology. Sperm motility, seminiferous tubule morphometry, testicular gene expression and fertility were not affected by treatment. There was no effect of D+Q treatment in ß-galactosidase activity and in lipofuscin staining in testes. D+Q treatment also did not affect body mass gain and testes mass. In conclusion, D+Q treatment increased serum testosterone levels and sperm concentration and decreased abnormal sperm morphology, however did not affect fertility. Further studies with older mice and different senolytics are necessary to elucidate the effects in the decline of sperm output (quality and quantity) associated with aging.
Assuntos
Quercetina , Testosterona , Feminino , Masculino , Animais , Camundongos , Quercetina/farmacologia , Dasatinibe/farmacologia , Senoterapia , Motilidade dos Espermatozoides , Sêmen/metabolismo , EspermatozoidesRESUMO
Ovarian reserve is a term used to estimate the total number of immature follicles present in the ovaries. Between birth and menopause, there is a progressive decrease in the number of ovarian follicles. Ovarian aging is a continuous physiological phenomenon, with menopause being the clinical mark of the end of ovarian function. Genetics, measured as family history for age at the onset of menopause, is the main determinant. However, physical activity, diet, and lifestyle are important factors that can influence the age of menopause. The low estrogen levels after natural or premature menopause increased the risk for several diseases, resulting in increased mortality risk. Besides that, the decreasing ovarian reserve is associated to reduced fertility. In women with infertility undergoing in vitro fertilization, reduced markers of ovarian reserve, including antral follicular count and anti-Mullerian hormone, are the main indicators of reduced chances of becoming pregnant. Therefore, it becomes clear that the ovarian reserve has a central role in women's life, affecting fertility early in life and overall health later in life. Based on this, the ideal strategy for delaying ovarian aging should have the following characteristics: (1) be initiated in the presence of good ovarian reserve; (2) maintained for a long period; (3) have an action on the dynamics of primordial follicles, controlling the rate of activation and atresia; and (4) safe use in pre-conception, pregnancy, and lactation. In this review, we therefore discuss some of these strategies and its feasibility for preventing a decline in the ovarian reserve.
Assuntos
Longevidade , Ovário , Gravidez , Humanos , Feminino , Ovário/fisiologia , Reprodução/fisiologia , Envelhecimento/fisiologia , Fertilidade/fisiologiaRESUMO
Crohn's disease (CD) and rheumatoid arthritis (RA) are immune mediated inflammatory diseases. Several studies indicate a role for microRNAs (miRNAs) in the pathogenesis of a variety of autoimmune diseases, including CD and RA. Our study's goal was to investigate circulating miRNAs in CD and RA patients to identify potential new biomarkers for early detection and personalized therapeutic approaches for autoimmune diseases. For this study, subjects with CD (n = 7), RA (n = 8) and healthy controls (n = 7) were recruited, and plasma was collected for miRNA sequencing. Comparison of the expression patterns of miRNAs between CD and healthy patients identified 99 differentially expressed miRNAs. Out of these miRNAs, 4 were down regulated, while 95 were up regulated. Comparison of miRNAs between RA and healthy patients identified 57 differentially expressed miRNAs. Out of those, 12 were down regulated, while 45 were up regulated. For all the miRNAs down regulated in CD and RA patients, 420 GO terms for biological processes were similarly regulated between both groups. Therefore, the identification of new plasma miRNAs allows the emergence of new biomarkers that can assist in the diagnosis and treatment of CD and RA.
RESUMO
Senescent cells are in a cell cycle arrest state and accumulate with aging and obesity, contributing to a chronic inflammatory state. Treatment with senolytic drugs dasatinib and quercetin (D + Q) can reduce senescent cell burden in several tissues, increasing lifespan. Despite this, there are few reports about senescent cells accumulating in female reproductive tissues. Therefore, the aim of the study was to characterize the ovarian reserve and its relationship with cellular senescence in genetically obese mice (ob/ob). In experiment 1, ob/ob (n = 5) and wild-type (WT) mice (n = 5) at 12 months of age were evaluated. In experiment 2, 2-month-old female ob/ob mice were treated with senolytics (D + Q, n = 6) or placebo (n = 6) during the 4 months. Obese mice had more senescent cells in ovaries, indicated by increased p21 and p16 and lipofuscin staining and macrophage infiltration. Treatment with D + Q significantly reduced senescent cell burden in ovaries of obese mice. Neither obesity nor treatment with D + Q affected the number of ovarian follicles. In conclusion, our data indicate that obesity due to leptin deficiency increases the load of senescent cells in the ovary, which is reduced by treatment by senolytics. However, neither obesity nor D + Q treatment affected the ovarian reserve.
Assuntos
Ovário , Senoterapia , Animais , Senescência Celular , Dasatinibe/farmacologia , Feminino , Camundongos , Camundongos Obesos , Obesidade/tratamento farmacológico , Quercetina/farmacologiaRESUMO
Growth hormone receptor knockout (GHRKO) mice are smaller, long living, and have an increased metabolic rate compared with normal (N) littermates. However, it is known that thermoneutral conditions (30-32°C) elicit metabolic adaptations in mice, increasing the metabolic rate. Therefore, we hypothesized that environmental temperature would affect the expression profile of different adipose tissue depots in GHRKO mice. For this, N (n = 12) and GHRKO (n = 11) male mice were maintained at 23 or 30°C from weaning until 11 months of age. RNA sequencing from adipose tissue depots (epididymal-eWAT, perirenal-pWAT, subcutaneous-sWAT, and brown fat-BAT) was performed. Thermoneutrality increased body weight gain in GHRKO mice, but not in N mice. Only a few genes were commonly regulated by temperature in N and GHRKO mice. The BAT was the most responsive to changes in temperature in both N and GHRKO mice. BAT Ucp1 and Ucp3 expression were decreased to a similar extent in both N and GHRKO mice under thermoneutrality. In contrast, eWAT was mostly unresponsive to changes in temperature. The response to thermoneutrality in GHRKO mice was most divergent from N mice in sWAT. Relative weight of sWAT was almost 4 times greater in GHRKO mice. Very few genes were regulated in N mice sWAT when compared with GHRKO mice. This suggests that this WAT depot has a central role in the adaptation of GHRKO mice to changes in temperature.
Assuntos
Tecido Adiposo Branco , Transcriptoma , Tecido Adiposo , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Hormônio do Crescimento/metabolismo , Masculino , Camundongos , Camundongos Knockout , Receptores da Somatotropina/genética , TemperaturaRESUMO
Evidence points to an important role of the growth hormone (GH) in the aging process and longevity. GH-deficient mice are smaller, live longer than normal littermates, and females have an increased ovarian reserve. The aim of the study was to evaluate the role of GH in the ovarian reserve by evaluating DNA damage, macrophage infiltration, and granulosa cell number in primordial and primary follicles. Experiment 1 used GH-deficient Ames dwarf mice (df/df, n = 12) and their normal littermates (N/df, n = 12), receiving GH or saline injections. Experiment 2 included transgenic mice overexpressing bovine GH (bGH) (n = 6) and normal mice (N, n = 6). DNA damage (anti-γH2AX) and macrophage counting (anti-CD68) were evaluated by immunofluorescence. Female df/df mice had lower γH2AX foci intensity in both oocytes and granulosa cells of primordial and primary follicles (p < 0.05), indicating fewer DNA double-strand breaks (DSBs). GH treatment increased DSBs in both df/df and N/df mice. Inversely, bGH mice had a higher quantity of DSBs in both oocytes and granulosa cells of primordial and primary follicles (p < 0.05). Df/df mice showed ovarian tissue with less macrophage infiltration than N/df mice (p < 0.05) and GH treatment increased macrophage infiltration (p < 0.05). In contrast, bGH mice had ovarian tissue with more macrophage infiltration compared to normal mice (p < 0.05). The current study shows that GH increases DNA DSBs in oocytes and granulosa cells and raises macrophage infiltration in the ovaries, pointing to the role of the GH/IGF-I axis in maintenance of oocyte DNA integrity and ovarian macrophage infiltration in mice.
Assuntos
Dano ao DNA , Hormônio do Crescimento , Macrófagos , Ovário , Animais , Bovinos , DNA , Feminino , Camundongos , Folículo OvarianoRESUMO
ABSTRACT Objective: The aim of this study was to evaluate the serum activity of PON1 in women according to SNPs L55M and T-107C and diet composition. Materials and methods: Blood and serum samples from 26 women were used. DNA extraction, PCR and digestion with restriction enzymes of the PCR fragment were performed for genotyping the PON1 SNPs T-107C and L55M. Serum PON1 activity was measured in a single time point. Patients completed the semi-quantitative food frequency questionnaire and diet composition was estimated. Results: Genotypic distribution for L55M SNP was 56% for the LL genotype, 32% for LM and 12% for MM; for the PON1 C(-107)T SNP it was 28% for the TT genotype, 41% for CT and 31% for CC. Individuals with C and L alleles had higher serum PON1 activity. Combining the two SNPs, we observed that individuals carrying the LL and CC genotypes had twice the activity of carriers of the TT and MM genotypes. Considering food intake, no significant difference was observed between genotypes and intake levels. Conclusion: PON1 T(-107)C and L55M SNPs exert a strong effect on serum PON1 activity in an additive manner and are more important than diet to predict serum PON1 activity.
Assuntos
Polimorfismo de Nucleotídeo Único , Arildialquilfosfatase/genética , Dieta , Alelos , GenótipoRESUMO
OBJECTIVE: The aim of this study was to evaluate the serum activity of PON1 in women according to SNPs L55M and T-107C and diet composition. METHODS: Blood and serum samples from 26 women were used. DNA extraction, PCR and digestion with restriction enzymes of the PCR fragment were performed for genotyping the PON1 SNPs T-107C and L55M. Serum PON1 activity was measured in a single time point. Patients completed the semi-quantitative food frequency questionnaire and diet composition was estimated. RESULTS: Genotypic distribution for L55M SNP was 56% for the LL genotype, 32% for LM and 12% for MM; for the PON1 C(-107)T SNP it was 28% for the TT genotype, 41% for CT and 31% for CC. Individuals with C and L alleles had higher serum PON1 activity. Combining the two SNPs, we observed that individuals carrying the LL and CC genotypes had twice the activity of carriers of the TT and MM genotypes. Considering food intake, no significant difference was observed between genotypes and intake levels. CONCLUSION: PON1 T(-107)C and L55M SNPs exert a strong effect on serum PON1 activity in an additive manner and are more important than diet to predict serum PON1 activity.
Assuntos
Arildialquilfosfatase , Dieta , Polimorfismo de Nucleotídeo Único , Alelos , Arildialquilfosfatase/genética , Feminino , Genótipo , HumanosRESUMO
Reduced inflammation, increased insulin sensitivity, and protection against cancer are shared between humans and mice with GH/IGF1 deficiency. Beyond hormone levels, miRNAs are important regulators of metabolic changes associated with healthy aging. We hypothesized that GH deficiency in humans alters the abundance of circulating miRNAs and that a subset of those miRNAs may overlap with those found in GH-deficient mice. In this study, subjects with untreated congenital isolated GH deficiency (IGHD; n = 23) and control subjects matched by age and sex (n = 23) were recruited and serum was collected for miRNA sequencing. Serum miRNAs from young (6 month) and old (22 month) Ames dwarf (df/df) mice with GH deficiency and their WT littermates (n = 5/age/genotype group) were used for comparison. We observed 14 miRNAs regulated with a genotype by age effect and 19 miRNAs regulated with a genotype effect independent of age in serum of IGHD subjects. These regulated miRNAs are known for targeting pathways associated with longevity such as mTOR, insulin signaling, and FoxO. The aging function was overrepresented in IGHD individuals, mediated by hsa-miR-31, hsa-miR-146b, hsa-miR-30e, hsa-miR-100, hsa-miR-181b-2, hsa-miR-195, and hsa-miR-181b-1, which target the FoxO and mTOR pathways. Intriguingly, miR-181b-5p, miR-361-3p, miR-144-3p, and miR-155-5p were commonly regulated in the serum of humans and GH-deficient mice. In vitro assays confirmed target genes for the main up-regulated miRNAs, suggesting miRNAs regulated in IGHD individuals can regulate the expression of age-related genes. These findings indicate that systemic miRNAs regulated in IGHD individuals target pathways involved in aging in both humans and mice.
Assuntos
Nanismo Hipofisário/genética , MicroRNAs/genética , Adulto , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-IdadeRESUMO
Cellular senescence contributes to age-related disorders including physical dysfunction, disabilities, and mortality caused by tissue inflammation and damage. Senescent cells accumulate in multiple tissues with aging and at etiological sites of multiple chronic disorders. The senolytic drug combination, Dasatinib plus Quercetin (D+Q), is known to reduce senescent cell abundance in aged mice. However, the effects of long-term D+Q treatment on intestinal senescent cell and inflammatory burden and microbiome composition in aged mice remain unknown. Here, we examine the effect of D+Q on senescence (p16Ink4a and p21Cip1) and inflammation (Cxcl1, Il1ß, Il6, Mcp1, and Tnfα) markers in small (ileum) and large (caecum and colon) intestine in aged mice (n = 10) compared to age-matched placebo-treated mice (n = 10). Additionally, we examine microbial composition along the intestinal tract in these mice. D+Q-treated mice show significantly lower senescent cell (p16 and p21 expression) and inflammatory (Cxcl1, Il1ß, Il6, Mcp1, and Tnfα expression) burden in small and large intestine compared with control mice. Further, we find specific microbial signatures in ileal, cecal, colonic, and fecal regions that are distinctly modulated by D+Q, with modulation being most prominent in small intestine. Further analyses reveal specific correlation of senescence and inflammation markers with specific microbial signatures. Together, these data demonstrate that the senolytic treatment reduces intestinal senescence and inflammation while altering specific microbiota signatures and suggest that the optimized senolytic regimens might improve health via reducing intestinal senescence, inflammation, and microbial dysbiosis in older subjects.
Assuntos
Dasatinibe , Microbioma Gastrointestinal , Quercetina , Animais , Biomarcadores , Senescência Celular/efeitos dos fármacos , Dasatinibe/farmacologia , Inflamação/tratamento farmacológico , Interleucina-6 , Intestinos , Camundongos , Quercetina/farmacologia , Senoterapia , Fator de Necrose Tumoral alfaRESUMO
The mammalian female is born with a limited ovarian reserve of primordial follicles. These primordial follicles are slowly activated throughout the reproductive lifecycle, thereby determining lifecycle length. Once primordial follicles are exhausted, women undergo menopause, which is associated with several metabolic perturbations and a higher mortality risk. Long before exhaustion of the reserve, females experience severe declines in fertility and health. As such, significant efforts have been made to unravel the mechanisms that promote ovarian aging and insufficiency. In this review, we explain how long-living murine models can provide insights in the regulation of ovarian aging. There is now overwhelming evidence that most life-span-extending strategies, and long-living mutant models simultaneously delay ovarian aging. Therefore, it appears that the same mechanisms that regulate somatic aging may also be modulating ovarian aging and germ cell exhaustion. We explore several potential contributing mechanisms including insulin resistance, inflammation, and DNA damage-all of which are hallmarks of cellular aging throughout the body including the ovary. These findings are in alignment with the disposable soma theory of aging, which dictates a trade-off between growth, reproduction, and DNA repair. Therefore, delaying ovarian aging will not only increase the fertility window of middle age females, but may also actively prevent menopausal-related decline in systemic health parameters, compressing the period of morbidity in mid-to-late life in females.
Assuntos
Envelhecimento/fisiologia , Folículo Ovariano/fisiologia , Reserva Ovariana/fisiologia , Animais , Restrição Calórica , Feminino , Fertilidade/fisiologia , Menopausa/fisiologia , Camundongos , Modelos AnimaisRESUMO
The aim of this study was to investigate the effect of calorie restriction (CR) during pregnancy in mice on metabolism and ovarian function in the offspring. Pregnant female mice were divided into two groups, a control group and a CR group (n=7 in each). Mice in the CR group were fed 50% of the amount consumed by control females from Day 10 of gestation until delivery. After weaning, the offspring received diet ad libitum until 3 months of age, when ovaries were collected. Ovaries were serially cut and every sixth section was used for follicle counting. Female offspring from CR dams tended to have increased bodyweight compared with offspring from control females (P=0.08). Interestingly, fewer primordial follicles (60% reduction; P=0.001), transitional follicles (P=0.0006) and total follicles (P=0.006) were observed in offspring from CR mothers. The number of primary, secondary and tertiary follicles did not differ between the groups (P>0.05). The CR offspring had fewer DNA double-strand breaks in primary follicle oocytes (P=0.03). In summary, CR during the second half of gestation decreased primordial ovarian follicle reserve in female offspring. These findings suggest that undernutrition during the second half of gestation may decrease the reproductive lifespan of female offspring.
Assuntos
Restrição Calórica/efeitos adversos , Reserva Ovariana/fisiologia , Fenômenos Fisiológicos da Nutrição Pré-Natal/fisiologia , Animais , Animais Recém-Nascidos , Feminino , Glucose/metabolismo , Masculino , Desnutrição/complicações , Desnutrição/metabolismo , Desnutrição/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Reprodução/fisiologiaRESUMO
The aim of this study was to evaluate the effect of growth hormone (GH) deficiency in primordial follicle reserve, DNA damage and macrophage infiltration in the ovaries of young mice. Ovaries from six-month-old GH-deficient Ames Dwarf (df/df) and Normal (N/df) mice were used. The number of primordial follicles was higher in df/df mice (p = 0.0026). Also, df/df mice had a lower number of primary (p = 0.023), secondary (p = 0.0052) and tertiary (p = 0.019) follicles. These findings indicate a slower rate of primordial follicle activation in df/df mice. Female df/df mice had decreased γH2AX foci intensity in oocytes of primordial (p = 0.015) and primary (p = 0.0004) follicles compared to N/df mice. Also, df/df mice had reduced γH2AX intensity in granulosa cells of primordial (p = 0.0002) and primary (p < 0.0001) follicles. Overall, this indicate to us that df/df mice accumulate less DNA damage in the ovarian reserve compared to N/df mice. Additionally, macrophage infiltration was also reduced in ovaries of df/df mice compared to N/df mice (p = 0.033). Interestingly, df/df mice had a reduced number of granulosa cells around primordial (p = 0.0024) and primary (p = 0.007) follicles compared to N/df mice. Also, df/df mice had a small diameter of primordial follicle nuclei (p = 0.0093), secondary follicle oocyte (p = 0.046) and tertiary follicle (p = 0.012). This points to the role of granulosa cell proliferation and oocyte growth for primordial follicle activation. The current study points to the role of the GH/IGF-I axis in extending lifespan of reproductive health, along with maintenance of oocyte DNA integrity and reduced ovarian inflammation.
Assuntos
Dano ao DNA , Macrófagos/fisiologia , Folículo Ovariano/fisiologia , Reserva Ovariana/genética , Animais , Feminino , Células da Granulosa/fisiologia , Hormônio do Crescimento/deficiência , Longevidade , Camundongos , Oócitos/fisiologia , Ovário/fisiologiaRESUMO
Growth hormone receptor knockout mice (GHRKO) have reduced body size and increased insulin sensitivity. These mice are known for having extended lifespan, healthspan and female reproductive longevity. Seventeen α-estradiol (17α-E2) is reported to increase insulin sensitivity and extend lifespan in male mice, with less robust effects in female mice. The aim of this study was to evaluate the ovarian reserve in wild type and GHRKO mice treated with 17α-E2. The mice were divided into four groups, GHRKO mice receiving a standard chow diet, GHRKO mice treated 17α-E2, wild type mice receiving a standard chow diet and WT mice treated with 17α-E2. 17α-E2 was provided in the diet for four months. IGF1 plasma concentrations and changes in body weight were assessed. Histological slides were prepared from the ovaries and the number of follicles was counted. GHRKO mice receiving the control diet had a greater number of primordial follicles and lower numbers of primary follicles compared to the other groups (pâ¯<â¯0.05). 17α-E2 treatment decreased the number of primordial follicles in GHRKO mice (pâ¯<â¯0.05), however had no effect in wild type mice. Treatment with 17α-E2 had no significant effect on the change in body weight during the experiment (pâ¯=â¯0.75). Plasma IGF1 concentrations were significantly lower in GHRKO mice as compared to wild type. In conclusion, we found that GHRKO mice displayed lesser primordial follicle activation as compared to wild type mice, but this phenotype was reversed by 17α-E2 administration, suggesting that ovarian aging is increased by 17α-E2 in long-living mice with extended reproductive longevity.