Ovariectomy Impaired Hepatic Glucose and Lipid Homeostasis and Altered the Gut Microbiota in Mice With Different Diets

Extracellular vesicles from cyclic mice modulate liver transcriptome in estroupause mice independent of age

Extracellular vesicles (EVs) of different sizes are secreted by cells and may contain microRNAs (miRNAs) among its cargo. These miRNAs in EVs can induce changes in gene expression and function of recipient cells. In different cells EVs content can change with age and physiological state affecting tissue function. Based on this, the aim of this study was to characterize the miRNA content and role of small EVs (sEVs) from cyclic female mice in the modulation of liver transcriptome in estropausal mice. Two-month-old female mice were induced to estropause using 4-vinylcyclohexene diepoxide (VCD). At six months of age, VCD-treated mice were divided into placebo group (VCD) and sEVs treated group (VCD + sEVs), which received 10 injections at 3-day intervals of sEVs isolated from serum of donor cyclic female mice. A group of cyclic mice also received placebo injection and served as controls (CTL). sEVs injection in mice undergoing estropause had no effect on body mass, insulin sensitivity or organ weight. We observed ten miRNAs differentially regulated in serum sEVs of VCD compared to CTL mice. In the liver we observed 931 genes differentially expressed in VCD + sEVs compared to VCD mice. Interestingly, eight pathways were up-regulated in liver by VCD treatment and down-regulated by sEVs treatment, indicating that sEVs from cyclic mice can reverse changes promoted by estropause in liver. The expression of Cyp4a12a, which is male-specific, was elevated in VCD females but not normalized by sEVs treatment. Our findings indicate that miRNA content in sEVs is regulated by estropause in mice independent of age. Additionally, treatment of estropausal mice with sEVs from cyclic mice can partially reverse changes in the liver transcriptome.

EXOSOMES FROM CYCLIC MICE MODULATE LIVER TRANSCRIPTOME IN ESTROUPAUSE MICE INDEPENDENT OF AGE

Background

Exosomes are extracellular vesicles secreted by cells that contain microRNAs (miRNAs). These miRNAs can induce changes in gene expression and function of recipient cells. In different cells exosome content can change with age and physiological state affecting tissues function and health.

Aims

Therefore, the aim of this study was to characterize the miRNA content and role of exosomes from cyclic female mice in the modulation of liver transcriptome in estropausal mice.

Main Methods

Two-month-old female mice were induced to estropause using 4-vinylcyclohexene diepoxide (VCD). At six months of age VCD-treated mice were divided in control group (VCD) and exosome treated group (VCD+EXO), which received 10 injections at 3-day intervals of exosomes extracted from serum of cyclic female mice (CTL).

Key findings

Exosome injection in estropausal mice had no effect on body mass, insulin sensitivity or organ weight. We observed ten miRNAs differentially regulated in serum exosomes of VCD compared to CTL mice. In the liver we observed 931 genes differentially expressed in VCD+EXO compared to VCD mice. Interestingly, eight pathways were up-regulated in liver by VCD treatment and down-regulated by exosome treatment, indicating that exosomes from cyclic mice can reverse changes promoted by estropause in liver. Cyp4a12a expression which is male-specific was increased in VCD females and not reversed by exosome treatment.

Significance

Our findings indicate that miRNAs content in exosomes is regulated by estropause in mice independent of age. Additionally, treatment of estropausal mice with exosomes from cyclic mice can partially reverse changes in liver transcriptome.

Essential Fatty Acids along the Women’s Life Cycle and Promotion of a Well-balanced Metabolism

Abstract:

Linoleic acid (ω-6 LA) and α-linolenic acid (ω-3 ALA) are essential fatty acids (EFA) for human beings. They must be consumed through diet and then extensively metabolized, a process that plays a fundamental role in health and eventually in disease prevention. Given the numerous changes depending on age and sex, EFA metabolic adaptations require further investigations along the women’s life cycle, from onset to decline of the reproductive age. Thus, this review explains women’s life cycle stages and their involvement in diet intake, digestion and absorption, the role of microbiota, metabolism, bioavailability, and EFA fate and major metabolites. This knowledge is crucial to promoting lipid homeostasis according to female physiology through well-directed health strategies. Concerning this, the promotion of breastfeeding, nutrition, and physical activity is cardinal to counteract ALA deficiency, LA/ALA imbalance, and the release of unhealthy derivatives. These perturbations arise after menopause that compromise both lipogenic and lipolytic pathways. The close interplay of diet, age, female organism, and microbiota also plays a central role in regulating lipid metabolism. Consequently, future studies are encouraged to propose efficient interventions for each stage of women's cycle. In this sense, plant-derived foods and products are promising to be included in women’s nutrition to improve EFA metabolism.

Ovariectomy and High Fat-Sugar-Salt Diet Induced Alzheimer's Disease/Vascular Dementia Features in Mice

While the vast majority of Alzheimer's disease (AD) is non-familial, the animal models of AD that are commonly used for studying disease pathogenesis and development of therapy are mostly of a familial form. We aimed to generate a model reminiscent of the etiologies related to the common late-onset Alzheimer's disease (LOAD) sporadic disease that will recapitulate AD/dementia features. Naïve female mice underwent ovariectomy (OVX) to accelerate aging/menopause and were fed a high fat-sugar-salt diet to expose them to factors associated with increased risk of development of dementia/AD. The OVX mice fed a high fat-sugar-salt diet responded by dysregulation of glucose/insulin, lipid, and liver function homeostasis and increased body weight with slightly increased blood pressure. These mice developed AD-brain pathology (amyloid and tangle pathologies), gliosis (increased burden of astrocytes and activated microglia), impaied blood vessel density and neoangiogenesis, with cognitive impairment. Thus, OVX mice fed on a high fat-sugar-salt diet imitate a non-familial sporadic/environmental form of AD/dementia with vascular damage. This model is reminiscent of the etiologies related to the LOAD sporadic disease that represents a high portion of AD patients, with an added value of presenting concomitantly AD and vascular pathology, which is a common condition in dementia. Our model can, thereby, provide a valuable tool for studying disease pathogenesis and for the development of therapeutic approaches.

Sodium sulphate ameliorates hypercholesterolemia via the upregulation of Cyp7a1 in hepatocytes and alleviates hepatic insulin resistance via the downregulation of Trib3 in mice with high cholesterol diets

Amelioration of hypercholesterolemia is essential for the treatment of atherosclerotic cardiovascular disease. Sodium sulphate is the effective component of mirabilite, which has been used in traditional Chinese medicine for the treatment of various diseases. In the present study, C57BL/6 mice were fed with a high-cholesterol diet (HCD) for 7 weeks and were treated with sodium sulphate in the last three of those weeks. Sodium sulphate significantly reduced the total cholesterol level and the low-density lipoprotein cholesterol/high-density lipoprotein cholesterol ratio in the serum of mice fed the HCD. In addition, cytochrome P450 7a1 and 39a1 were significantly upregulated in the livers of mice treated with sodium sulphate. Furthermore, tribbles pseudokinase 3 expression was significantly increased in the livers of mice fed the HCD, but was significantly reduced by sodium sulphate treatment. In terms of the insulin signaling pathway, the ratio of phosphorylated AKT to total AKT in the livers of mice fed the HCD was significantly lower compared with that of control mice fed a normal diet, but was significantly increased by sodium sulphate treatment. Sodium sulphate treatment also reduced the levels of fibroblast growth factor (FGF)15 in the ileum and inhibited the FGF15/FGF receptor 4-Klotho β/c-Jun N-terminal kinase/c-Jun signaling pathway in the livers of mice fed the HCD. In addition, sodium sulphate changed the composition of the gut microbiota of mice fed the HCD. In conclusion, sodium sulphate may mitigate hypercholesterolemia and hepatic insulin resistance in mice fed an HCD.

Effects of High-Grain Diet on Performance, Ruminal Fermentation, and Rumen Microbial Flora of Lactating Holstein Dairy Cows

The objectives of the current study were to evaluate the fluctuations in production performance, rumen fermentation, and microbial community in lactating dairy cows fed a high-grain diet (HG). In this study, 16 healthy Holstein lactating dairy cattle with similar milk yields of 16.80 ± 4.30 kg/d, days in milk 171.44 ± 23.25 days, and parity 2.2 ± 1.5 times were selected and randomly allocated into two groups. One group was fed a low-grain diet (LG; 40% concentrate, DM basis; n = 8), and the other group was fed a high-grain diet (HG; 60% concentrate, DM basis; n = 8). The experiment lasted 6 weeks, including 1 week for adaptation. The experimental results showed that the milk fat content in the milk of lactating cows in the HG group was significantly reduced (p < 0.05), and the milk urea nitrogen (MUN) content showed an increasing trend (0.05 < p < 0.10) compared with the LG group. Compared with the LG group, rumen fluid pH was significantly decreased after feeding a high-grain diet, and contents of total volatile fatty acids (TVFA), acetate, propionate, and butyrate were significantly increased (p < 0.05). The acetate/propionate significantly decreased (p < 0.05). HG group significantly increased the abundance of Prevotella and Bacteroides in rumen fluid while significantly reducing the abundance of Methanobrevibacter and Lachnospiraceae ND3007_group (p < 0.05). Microorganisms with LDA scores > 2 were defined as unique, with the bacterial genus Anaerorhabdus_furcosa_group identified as a biomarker for the LG group, and the unique bacterial genus in the HG group were Prevotella, Stenotrophomonas, and Xanthomonadaceae. The prediction results of microbial function showed that a total of 18 KEGG differential pathways were generated between the two treatment groups, mainly manifested in metabolic pathways, signal transduction, and the immune system. In conclusion, the HG group promoted rumen fermentation by altering the microbial composition of lactating cows. Our findings provide a theoretical basis for the rational use of high-grain diets to achieve high yields in intensive dairy farming.

The downregulation of tight junction proteins and pIgR in the colonic epithelium causes the susceptibility of EpCAM+/- mice to colitis and gut microbiota dysbiosis

Background

The genetic factors play important roles on the pathogenesis of inflammatory bowel disease (IBD). EpCAM is highly expressed in the intestinal epithelium. It is still unclear if the decrease or somatic mutation of EpCAM could cause IBD.

Methods

The WT and EpCAM+/- mice were administrated with DSS intermittently for nearly 8 weeks. The colon, liver and feces were harvested to check the morphological and histological changes, the expression of inflammatory genes and the gut microbiota via H&E staining, immunofluorescence, qPCR, western blot and 16S rDNA sequence assays.

Results

The DSS administration induced more serious inflammation in the colon of EpCAM+/- mice than WT mice. Compared to DSS-induced WT mice, the transcriptional levels of IL-6, F4/80, Ly6g, Ly6d and Igha were significantly higher in the colon of DSS-induced EpCAM+/- mice. The protein levels of MMP7 and MMP8 and the activation of JNK, ERK1/2 and p38 were significantly increased in the colon of DSS-induced EpCAM+/- mice. The protein levels of CLDN1, CLDN2, CLDN3, CLDN7, OCLD, ZO-1 and pIgR were significantly decreased in the colon of DSS-induced EpCAM+/- mice. The serum concentration of LPS was significantly higher in the DSS-induced EpCAM+/- mice which caused the acute inflammation in the liver of them. The expression of Pigr was significantly reduced in the liver of DSS-induced EpCAM+/- mice. The ratio of Firmicutes/Bacteroidetes at the phylum level was higher in the gut microbiota of EpCAM+/- mice than WT mice.

Conclusion

In conclusion, the heterozygous mutation of EpCAM increased the susceptibility to colitis, gut microbiota dysbiosis and liver injury.

Hypothalamic inflammation and the development of an obese phenotype induced by high-fat diet consumption is exacerbated in alpha7 nicotinic cholinergic receptor knockout mice

Hypothalamic inflammation and metabolic changes resulting from the consumption of high-fat diets have been linked to low grade inflammation and obesity. Inflammation impairs the hypothalamic expression of α7 nicotinic acetylcholine receptor (α7nAChR). The α7nAChR is described as the main component of the anti-inflammatory cholinergic pathway in different inflammation models. To assess whether the reduction in α7nAChR expression exacerbates hypothalamic inflammation induced by a high-fat diet (HFD), were used male and female global α7nAChR knockout mouse line in normal or high-fat diet for 4 weeks. Body weight gain, adiposity, glucose homeostasis, hypothalamic inflammation, food intake, and energy expenditure were evaluated. Insulin sensitivity was evaluated in neuronal cell culture. Consumption of an HFD for 4 weeks resulted in body weight gain and adiposity in male Chrna7-/- mice and the hypothalamus of male Chrna7-/- mice showed neuroinflammatory markers, with increased gene expression of pro-inflammatory cytokines and dysregulation in the nuclear factor kappa B pathway. Moreover, male Chrna7-/- mice consuming an HFD showed alterations in glucose homeostasis and serum of Chrna7-/- mice that consumed an HFD impaired insulin signalling in neuronal cell culture experiments. In general, female Chrna7-/- mice that consumed an HFD did not show the phenotypic and molecular changes found in male mice, indicating that there is sexual dimorphism in the analysed parameters. Thus, receptor deletion resulted in increased susceptibility to hypothalamic inflammation and metabolic damage associated with HFD consumption in male mice.

Hepatobiliary and pancreatic: Multi-donor fecal microbiota transplantation attenuated high-fat diet-induced hepatic steatosis in mice by remodeling the gut microbiota

BACKGROUND AND AIMS

Fecal microbiota transplantation (FMT) can improve the symptoms of nonalcoholic fatty liver disease (NAFLD) by restoring the gut microbiota. This study was aimed to evaluate the therapeutic effects of single-donor (SD) or multi-donor (MD) FMT in a mouse model of hepatic steatosis and explore the underlying mechanisms.

METHODS

Fecal samples were collected from NAFLD patients and healthy controls with similar baseline characteristics, with gut microbiota analyzed. Mice were fed either a normal-chow diet (NCD) or a high-fat diet (HFD) for 3 weeks and then administered fecal microbiota collected from healthy SDs or MDs for 12 weeks.

RESULTS

Fecal samples from NAFLD patients showed significantly lower microbial diversity than those from healthy controls. MD-FMT reduced liver fat accumulation and body weight and significantly improved serum and liver biochemical indices in HFD-fed mice. Compared to untreated HFD-fed mice, MD-FMT significantly decreased the relative expression of IL-1β, IL-6, TNF-α, IFN-γ, and IL-1β mRNAs in the liver. The relative protein level of intestinal barrier components, including claudin-1, occludin, and E-cadherin, as well as serum lipopolysaccharide (LPS) level in mice, were found to be improved following MD-FMT intervention. Furthermore, FMT reversed HFD-induced gut dysbiosis and increased the abundance of beneficial bacteria such as Blautia and Akkermansia.

CONCLUSION

NAFLD patients and healthy controls showed distinct gut microbiota. Likewise, HFD altered gut microbiota in mice compared to NCD-fed controls. MD-FMT restored gut dysbiosis in HFD-fed mice and attenuated liver steatosis, and should be considered as an effective treatment option for NAFLD.

Timing Matters: Effects of Early and Late Estrogen Replacement Therapy on Glucose Metabolism and Vascular Reactivity in Ovariectomized Aged Wistar Rats

Cardiovascular disease incidence increases after menopause due to the loss of estrogen cardioprotective effects. However, there are conflicting data regarding the timing of estrogen therapy (ERT) and its effect on vascular dysfunction associated with impaired glucose metabolism. The aim of this work was to evaluate the effect of early and late ERT on blood glucose/insulin balance and vascular reactivity in aged ovariectomized Wistar rats. Eighteen-month-old female Wistar rats were randomized as follows: (1) sham, (2) 10-week postovariectomy (10 w), (3) 10 w postovariectomy+early estradiol therapy (10 w-early E2), (4) 20-week postovariectomy (20 w), and (5) 20-week postovariectomy+late estradiol therapy (20 w-late E2). Early E2 was administered 3 days after ovariectomy and late therapy after 10 weeks, in both groups. 17β-Estradiol (E2) was administered daily for 10 weeks (5 μg/kg/day). Concentration-response curves to angiotensin II, KCl, and acetylcholine (ACh) were performed. Heart rate (HR), diastolic and systolic blood pressure (DBP and SBP), glucose, insulin, HOMA-IR, and nitric oxide (NO) levels were determined. Higher glucose levels were found in all groups compared to the sham group, except the 20 w-late E2 group. Insulin was increased in all ovariectomized groups compared to sham. The HOMA-IR index showed insulin resistance in all ovariectomized groups, except for the 10 w-early E2 group. The 10 w-early E2 group increased NO levels vs. the 10 w group. After 10 w postovariectomy, the vascular response to KCl and Ach increases, despite early E2 administration. Early and late E2 treatment decreased vascular reactivity to Ang II. At 20-week postovariectomy, DBP increased, even with E2 administration, while SBP and HR remained unchanged. The effects of E2 therapy on blood glucose/insulin balance and vascular reactivity depend on the timing of therapy. Early ERT may provide some protective effects on insulin resistance and vascular function, whereas late ERT may not have the same benefits.

Gut Microbiota and Acylcarnitine Metabolites Connect the Beneficial Association between Estrogen and Lipid Metabolism Disorders in Ovariectomized Mice

Decreased estrogen level is one of the main causes of lipid metabolism disorders and coronary heart disease in women after menopause. Exogenous estradiol benzoate is effective to some extent in alleviating lipid metabolism disorders caused by estrogen deficiency. However, the role of gut microbes in the regulation process is not yet appreciated. The objective of this study was to investigate the effects of estradiol benzoate supplementation on lipid metabolism, gut microbiota, and metabolites in ovariectomized (OVX) mice and to reveal the importance of gut microbes and metabolites in the regulation of lipid metabolism disorders. This study found that high doses of estradiol benzoate supplementation effectively attenuated fat accumulation in OVX mice. There was a significant increase in the expression of genes enriched in hepatic cholesterol metabolism and a concomitant decrease in the expression of genes enriched in unsaturated fatty acid metabolism pathways. Further screening of the gut for characteristic metabolites associated with improved lipid metabolism revealed that estradiol benzoate supplementation influenced major subsets of acylcarnitine metabolites. Ovariectomy significantly increased the abundance of characteristic microbes that are significantly negatively associated with acylcarnitine synthesis, such as Lactobacillus and Eubacterium ruminantium group bacteria, while estradiol benzoate supplementation significantly increased the abundance of characteristic microbes that are significantly positively associated with acylcarnitine synthesis, such as Ileibacterium and Bifidobacterium spp. The use of pseudosterile mice with gut microbial deficiency greatly facilitated the synthesis of acylcarnitine due to estradiol benzoate supplementation and also alleviated lipid metabolism disorders to a greater extent in OVX mice. IMPORTANCE Our findings establish a role for gut microbes in the progression of estrogen deficiency-induced lipid metabolism disorders and reveal key target bacteria that may have the potential to regulate acylcarnitine synthesis. These findings suggest a possible route for the use of microbes or acylcarnitine to regulate disorders of lipid metabolism induced by estrogen deficiency.

Caloric restriction prevents inflammation and insulin dysfunction in middle-aged ovariectomized mice

BACKGROUND

Loss of ovarian function is associated with increased visceral fat. In this study, we aimed to study the effects of caloric restriction (CR) on metabolism in ovariectomized mice.

METHODS AND RESULTS

Female, 8-12-month-old mice were divided into three groups: OVX (ovariectomized mice), OVXR (40% CR) and Sham. CR increased insulin sensitivity and glucose tolerance. AMPK phosphorylation was observed in the liver of OVXR mice. CR also increased hepatic cholesterol and triglyceride levels. The reductions in the level of TBARS in the serum and liver and of H2O2 in the liver of OVXR mice suggested alterations in the redox state of the liver. Although expression of catalase protein was reduced by CR, expression of superoxide dismutase was not altered by CR. Although interleukin IL-6 and IL-10 levels in OVXR mice were similar to those in Sham mice, macrophage infiltration was reduced in OVXR mice. OVXR mice had increased sirtuin1 levels and decreased sirtuin3 levels in the liver.

CONCLUSIONS

In conclusion, CR improved the condition of ovariectomized mice by reducing adiposity and increasing insulin sensitivity and glucose tolerance through a mechanism that may involve AMPK.

Mechanic Insight into the Distinct and Common Roles of Ovariectomy Versus Adrenalectomy on Adipose Tissue Remodeling in Female Mice

Dysfunctions of the ovaries and adrenal glands are both evidenced to cause aberrant adipose tissue (AT) remodeling and resultant metabolic disorders, but their distinct and common roles are poorly understood. In this study, through biochemical, histological and RNA-seq analyses, we comprehensively explored the mechanisms underpinning subcutaneous (SAT) and visceral adipose tissue (VAT) remodeling, in response to ovariectomy (OVX) versus adrenalectomy (ADX) in female mice. OVX promoted adipocyte differentiation and fat accumulation in both SAT and VAT, by potentiating the Pparg signaling, while ADX universally prevented the cell proliferation and extracellular matrix organization in both SAT and VAT, likely by inactivating the Nr3c1 signaling, thus causing lipoatrophy in females. ADX, but not OVX, exerted great effects on the intrinsic difference between SAT and VAT. Specifically, ADX reversed a large cluster of genes differentially expressed between SAT and VAT, by activating 12 key transcription factors, and thereby caused senescent cell accumulation, massive B cell infiltration and the development of selective inflammatory response in SAT. Commonly, both OVX and ADX enhance circadian rhythmicity in VAT, and impair cell proliferation, neurogenesis, tissue morphogenesis, as well as extracellular matrix organization in SAT, thus causing dysfunction of adipose tissues and concomitant metabolic disorders.

Xiaotangzhike Pill Attenuates the Progression of Diabetes In Vivo through the Mediation of the Akt/GSK-3β Axis

Background

Diabetes seriously threatens the health of people. Traditional Chinese medicine has been proven to inhibit the progression of diabetes. Meanwhile, the Xiaotangzhike pill (XTZK) was known to alleviate the symptom of diabetes. Thus, this research decided to investigate the mechanism underlying the impact of XTZK in diabetes remains unexplored.

Methods

To assess the impact of XTZK in diabetes, in vivo model of diabetes was constructed. The contents of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), and high-density lipoprotein cholesterol (HDL-C) in the rats were tested by the commercial kits. In addition, Masson and hematoxylin and eosin (H&E) staining were applied for assessing the histological changes and fibrosis in the rats, respectively. Furthermore, a western blot was applied to assess the protein levels.

Results

Streptozotocin (STZ) significantly increased the levels of area under the curve (AUC), TG, TC, LDL-C, and decreased the contents of HDL-C in rats, while these phenomena were partially reversed by XTZK. In addition, STZ notably induced inflammatory infiltration and fibrosis in the liver tissues of rats, which was greatly restored by XTZK. The levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and malondialdehyde (MDA) in the serum of rats were notably upregulated by STZ, while the effect of STZ was markedly abolished by XTZK. Meanwhile, STZ-caused the upregulation of p-Smad2 and α-SMA in rats was restored by XTZK. Furthermore, XTZK notably inhibited the progression of Qi and Yin deficiency syndrome in diabetes through the mediation of the Akt/GSK-3β axis.

Conclusion

The Xiaotangzhike pill attenuates the progression of diabetes through the mediation of the Akt/GSK-3β axis. Hence, our study might supply a novel insight into discovering new strategies against diabetes.

Metabolic differences in women with premature ovarian insufficiency: a systematic review and meta-analysis

Objective

This review aimed to investigate the metabolic profile of women with premature ovarian insufficiency (POI) compared relative to women with normal ovarian functioning.

Methods

A systematic search of PubMed, EMBASE, and the Web of Science for observational studies published up until the 6^th of July 2021 that compared the metabolic profile of POI women with a healthy control group were assessed. Mean differences (MD) and 95% confidence interval (CI) were pooled using the fixed or random effect models.

Results

A total of 21 studies involving 1573 women with POI and 1762 control women were included. POI patients presented significantly higher waist circumference, total cholesterol, low-density lipoprotein, high-density lipoprotein, triglycerides, and fasting glucose. Additionally, POI patients had marginally higher insulin level. However, the differences in systolic, and diastolic blood pressure were non-significant relative to the control group.

Conclusions

POI is associated with alterations in certain metabolic parameters compared to control women. This finding highlights the importance of early screening and the lifelong management of metabolic health for women with POI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13048-022-01041-w.

Ginsenoside Rb1 improves intestinal aging via regulating the expression of sirtuins in the intestinal epithelium and modulating the gut microbiota of mice

Intestinal aging seriously affects the absorption of nutrients of the aged people. Ginsenoside Rb1 (GRb1) which has multiple functions on treating gastrointestinal disorders is one of the important ingredients from Ginseng, the famous herb in tradition Chinese medicine. However, it is still unclear if GRb1 could improve intestinal aging. To investigate the function and mechanism of GRb1 on improving intestinal aging, GRb1 was administrated to 104-week-old C57BL/6 mice for 6 weeks. The jejunum, colon and feces were collected for morphology, histology, gene expression and gut microbiota tests using H&E staining, X-gal staining, qPCR, Western blot, immunofluorescence staining, and 16S rDNA sequencing technologies. The numbers of cells reduced and the accumulation of senescent cells increased in the intestinal crypts of old mice, and administration of GRb1 could reverse them. The protein levels of CLDN 2, 3, 7, and 15 were all decreased in the jejunum of old mice, and administration of GRb1 could significantly increase them. The expression levels of Tert, Lgr5, mKi67, and c-Myc were all significantly reduced in the small intestines of old mice, and GRb1 significantly increased them at transcriptional or posttranscriptional levels. The protein levels of SIRT1, SIRT3, and SIRT6 were all reduced in the jejunum of old mice, and GRb1 could increase the protein levels of them. The 16S rDNA sequencing results demonstrated the dysbiosis of the gut microbiota of old mice, and GRb1 changed the composition and functions of the gut microbiota in the old mice. In conclusion, GRb1 could improve the intestinal aging via regulating the expression of Sirtuins family and modulating the gut microbiota in the aged mice.

The effects of microbiota on reproductive health: A review

Reproductive issues are becoming an increasing global problem. There is increasing interest in the relationship between microbiota and reproductive health. Stable microbiota communities exist in the gut, reproductive tract, uterus, testes, and semen. Various effects (e.g., epigenetic modifications, nervous system, metabolism) of dysbiosis in the microbiota can impair gamete quality; interfere with zygote formation, embryo implantation, and embryo development; and increase disease susceptibility, thus adversely impacting reproductive capacity and pregnancy. The maintenance of a healthy microbiota can protect the host from pathogens, increase reproductive potential, and reduce the rates of adverse pregnancy outcomes. In conclusion, this review discusses microbiota in the male and female reproductive systems of multiple animal species. It explores the effects and mechanisms of microbiota on reproduction, factors that influence microbiota composition, and applications of microbiota in reproductive disorder treatment and detection. The findings support novel approaches for managing reproductive diseases through microbiota improvement and monitoring. In addition, it will stimulate further systematic explorations of microbiota-mediated effects on reproduction.

Dietary regulations for microbiota dysbiosis among post-menopausal women with type 2 diabetes

Type 2 diabetes (T2D) and T2D-associated comorbidities, such as obesity, are serious universally prevalent health issues among post-menopausal women. Menopause is an unavoidable condition characterized by the depletion of estrogen, a gonadotropic hormone responsible for secondary sexual characteristics in women. In addition to sexual dimorphism, estrogen also participates in glucose-lipid homeostasis, and estrogen depletion is associated with insulin resistance in the female body. Estrogen level in the gut also regulates the microbiota composition, and even conjugated estrogen is actively metabolized by the estrobolome to maintain insulin levels. Moreover, post-menopausal gut microbiota is different from the pre-menopausal gut microbiota, as it is less diverse and lacks the mucolytic Akkermansia and short-chain fatty acid (SCFA) producers such as Faecalibacterium and Roseburia. Through various metabolites (SCFAs, secondary bile acid, and serotonin), the gut microbiota plays a significant role in regulating glucose homeostasis, oxidative stress, and T2D-associated pro-inflammatory cytokines (IL-1, IL-6). While gut dysbiosis is common among post-menopausal women, dietary interventions such as probiotics, prebiotics, and synbiotics can ease post-menopausal gut dysbiosis. The objective of this review is to understand the relationship between post-menopausal gut dysbiosis and T2D-associated factors. Additionally, the study also provided dietary recommendations to avoid T2D progression among post-menopausal women.

From Menopause to Neurodegeneration-Molecular Basis and Potential Therapy

The impacts of menopause on neurodegenerative diseases, especially the changes in steroid hormones, have been well described in cell models, animal models, and humans. However, the therapeutic effects of hormone replacement therapy on postmenopausal women with neurodegenerative diseases remain controversial. The steroid hormones, steroid hormone receptors, and downstream signal pathways in the brain change with aging and contribute to disease progression. Estrogen and progesterone are two steroid hormones which decline in circulation and the brain during menopause. Insulin-like growth factor 1 (IGF-1), which plays an import role in neuroprotection, is rapidly decreased in serum after menopause. Here, we summarize the actions of estrogen, progesterone, and IGF-1 and their signaling pathways in the brain. Since the incidence of Alzheimer’s disease (AD) is higher in women than in men, the associations of steroid hormone changes and AD are emphasized. The signaling pathways and cellular mechanisms for how steroid hormones and IGF-1 provide neuroprotection are also addressed. Finally, the molecular mechanisms of potential estrogen modulation on N-methyl-d-aspartic acid receptors (NMDARs) are also addressed. We provide the viewpoint of why hormone therapy has inconclusive results based on signaling pathways considering their complex response to aging and hormone treatments. Nonetheless, while diagnosable AD may not be treatable by hormone therapy, its preceding stage of mild cognitive impairment may very well be treatable by hormone therapy.