Astragalin, a Flavonoid from Morus alba (Mulberry) Increases Endogenous Estrogen and Progesterone by Inhibiting Ovarian Granulosa Cell Apoptosis in an Aged Rat Model of Menopause

The DNA double-strand break repair proteins γH2AX, RAD51, BRCA1, RPA70, KU80, and XRCC4 exhibit follicle-specific expression differences in the postnatal mouse ovaries from early to older ages

PURPOSE

Ovarian aging is closely related to a decrease in follicular reserve and oocyte quality. The precise molecular mechanisms underlying these reductions have yet to be fully elucidated. Herein, we examine spatiotemporal distribution of key proteins responsible for DNA double-strand break (DSB) repair in ovaries from early to older ages. Functional studies have shown that the γH2AX, RAD51, BRCA1, and RPA70 proteins play indispensable roles in HR-based repair pathway, while the KU80 and XRCC4 proteins are essential for successfully operating cNHEJ pathway.

METHODS

Female Balb/C mice were divided into five groups as follows: Prepuberty (3 weeks old; n = 6), puberty (7 weeks old; n = 7), postpuberty (18 weeks old; n = 7), early aged (52 weeks old; n = 7), and late aged (60 weeks old; n = 7). The expression of DSB repair proteins, cellular senescence (β-GAL) and apoptosis (cCASP3) markers was evaluated in the ovaries using immunohistochemistry.

RESULT

β-GAL and cCASP3 levels progressively increased from prepuberty to aged groups (P < 0.05). Notably, γH2AX levels varied in preantral and antral follicles among the groups (P < 0.05). In aged groups, RAD51, BRCA1, KU80, and XRCC4 levels increased (P < 0.05), while RPA70 levels decreased (P < 0.05) compared to the other groups.

CONCLUSIONS

The observed alterations were primarily attributed to altered expression in oocytes and granulosa cells of the follicles and other ovarian cells. As a result, the findings indicate that these DSB repair proteins may play a role in the repair processes and even other related cellular events in ovarian cells from early to older ages.

New potential selective estrogen receptor modulators in traditional Chinese medicine for treating menopausal syndrome

Women go through several predictable conditions and symptoms during menopause that are caused by age, changes in sex hormone levels, and other factors. Conventional menopause hormone therapy has raised serious concerns about the increased risks of cancers, blood clots, depression, etc. Selective estrogen receptor modulators (SERMs) that can be both agonists and antagonists of estrogen receptors in a tissue-specific manner are being developed to reduce the health concerns associated with menopause hormone therapy. Here, we have searched the Chinese national traditional Chinese medicine (TCM) patent database to identify potential SERM-like compounds with reduced health risks. TCM has been widely used for treating complex symptoms associated with menopause syndrome and thus can be a particularly rich source for pharmaceutical alternatives with SERM properties. After extensive literature review and molecular simulation, we conclude that protopanaxatriol, paeoniflorin, astragalin, catalpol, and hyperoside among others may be particularly promising as SERM-like compounds in treating the menopausal syndrome. Compounds in TCM hold promise in yielding comparable outcomes to hormone therapy but with reduced associated risks, thus presenting promising avenues for their clinical applications.

Astragalin from Thesium chinense: A Novel Anti-Aging and Antioxidant Agent Targeting IGFR/CD38/Sirtuins

Astragalin (AG), a typical flavonoid found in Thesium chinense Turcz (T. chinense), is abundant in various edible plants and possesses high nutritional value, as well as antioxidant and antibacterial effects. In this study, we initially predicted the mechanism of action of AG with two anti-aging and antioxidant-related protein targets (CD38 and IGFR) by molecular docking and molecular dynamics simulation techniques. Subsequently, we examined the anti-aging effects of AG in Caenorhabditis elegans (C. elegans), the antioxidant effects in zebrafish, and verified the related molecular mechanisms. In C. elegans, AG synergistically extended the lifespan of C. elegans by up-regulating the expression of daf-16 through inhibiting the expression of daf-2/IGFR and also activating the AMPK and MAPK pathways to up-regulate the expression of sir-2.1, sir-2.4, and skn-1. In oxidatively damaged zebrafish embryos, AG demonstrated a synergistic effect in augmenting the resistance of zebrafish embryos to oxidative stress by up-regulating the expression levels of SIRT1 and SIRT6 within the zebrafish embryos system via the suppression of CD38 enzymatic activity and then inhibiting the expression of IGFR through high levels of SIRT6. These findings highlight the antioxidant and anti-aging properties of AG and indicate its potential application as a supplementary ingredient in aquaculture for enhancing fish health and growth.

Phytotherapeutic approach for conquering menopausal syndrome and osteoporosis

Women face a significant change in their reproductive health as menopause sets in. It is marred with numerous physiological changes that negatively impact their quality of life. This universal, transition phase is associated with menopausal and postmenopausal syndrome, which may spread over 2-10 years. This creates a depletion of female hormones causing physical, mental, sexual and social problems and may, later on, manifest as postmenopausal osteoporosis leading to weak bones, causing fractures and ultimately morbidity and mortality. Menopausal hormone therapy generally encompasses the correction of hormone balance through various pharmacological agents, but the associated side effects often lead to cessation of therapy with poor clinical outcomes. However, it has been noticed that phytotherapeutics is trusted by women for the amelioration of symptoms related to menopause and for improving bone health. This could primarily be due to their reduced side effects and lesser costs. This review attempts to bring forth the suitability of phytotherapeutics/herbals for the management of menopausal, postmenopausal syndrome, and menopausal osteoporosis through several published research. It tries to enlist the available botanicals with their key constituents and mechanism of action for mitigating symptoms associated with menopause as well as osteoporosis. It also includes a list of a few herbal commercial products available for these complications. The article also intends to collate the findings of various clinical trials and patents available in this field and provide a window for newer research avenues in this highly important yet ignored health segment.

Astragalin: a food-origin flavonoid with therapeutic effect for multiple diseases

Naturally occurring flavonoids have long been utilized as essential templates for the development of novel drugs and as critical ingredients for functional foods. Astragalin (AG) is a natural flavonoid that can be isolated from a variety of familiar edible plants, such as the seeds of green tea, Morus alba L., and Cuscuta chinensis. It is noteworthy that AG has a wide range of pharmacological activities and possesses therapeutic effects against a variety of diseases, covering cancers, osteoarthritis, osteoporosis, ulcerative colitis, mastitis, obesity, diabetes mellitus, diabetic complications, ischemia/reperfusion injury, neuropathy, respiratory diseases, and reproductive system diseases. This article reviewed the natural source and pharmacokinetics of AG and systematically summarized the pharmacological activities and potential mechanisms of AG in treating diverse diseases in order to promote the development of AG as a functional food, in doing so providing references for its clinical application in disease therapy.

Astragalin attenuates depression-like behaviors and memory deficits and promotes M2 microglia polarization by regulating IL-4R/JAK1/STAT6 signaling pathway in a murine model of perimenopausal depression

RATIONALE

Neuroinflammation can be alleviated via M2 microglia polarization, which could promote the recovery of perimenopausal depression. Astragalin (AST) possesses anti-neuroinflammatory activity. However, the effects of AST on perimenopausal depression and the molecular mechanism in regulating microglia polarization remained unknown.

OBJECTIVES

The purpose was to investigate the effects of AST on mice with simulated perimenopausal depression through regulating microglia polarization. It was aimed to clarify the molecular mechanism related to the interleukin-4 receptor (IL-4R)/janus kinase (JAK) 1/signal transducer and activator of transcription (STAT) 6 signaling pathway.

METHODS

The ovariectomy (OVX)/chronic unpredictable mild stress (CUMS)-induced murine model of perimenopausal depression was established and treated with AST. Then the depression-like behaviors and cognitive ability of mice were examined. After that, we detected the markers of microglia polarization and its regulatory signals. In addition, lipopolysaccharides (LPS)/adenosine triphosphate (ATP)-induced inflammatory BV2 model were used to verify the potential molecular mechanism.

RESULTS

AST alleviated perimenopausal depression-like behaviors and memory deficits. AST alleviated microglia activation and increased Ki67-positive cells in dentate gyrus (DG). The viability of BV2 decreased by LPS/ATP was raised by AST. Moreover, both in vivo and in vitro, AST switched microglia from M1 phenotype caused by OVX/CUMS or LPS/ATP to M2 phenotype. The IL-4R/JAK1/STAT6 signaling was restored, and the levels of inducible nitric oxide synthase (iNOS), nuclear NF-KappaB-p65 were reduced by AST. Importantly, AST showed prevention against the ubiquitination modification and degradation of STAT6.

CONCLUSIONS

Our results revealed new insights into molecular mechanism associated with microglia polarization in the effect of AST on the mouse model of perimenopausal depression.

He's Yangchao Recipe Ameliorates Ovarian Oxidative Stress of Aging Mice under Consecutive Superovulation Involving JNK- And P53-Related Mechanism

Objective

To evaluate the effects of He's Yangchao Recipe (HSYC) on ameliorating ovarian oxidative stress of aging mice under consecutive superovulation.

Methods

An 8-month-old C57BL/6 female mouse was chosen to establish an aging model under ovarian hyperstimulation. Mice were randomly separated into four groups: R1 as the control group, R4 as the model group, NR4 with N-acetyl-L-cysteine (NAC) administration, and TR4 with HSYC administration. Oocyte collection, in vitro fertilization, and embryo culture were performed. The serum hormone levels were measured by enzyme-linked immunosorbent assays (ELISA); the reactive oxygen species (ROS) level of oocytes, the number of growing follicles, corpus luteum, ovulated oocytes, and developing embryos at each stage, along with the proportions of fragmented oocytes and abnormal mitochondria in granulosa cells (GCs) and the apoptosis rate of GCs were calculated; the mRNA and protein levels of JNK, P53, BAX were detected by real-time PCR and the Simple Western System.

Results

HSYC enhanced estradiol, progesterone, and inhibin-B levels and increased growing follicle and corpus luteum and ovulated egg counts compared to the R4 group (P < 0.05), whereas it decreased the proportions of fragmented oocytes (P < 0.01); Meanwhile, embryos from mice subjected to four superovulation cycles with HSYC treated had a higher hatching potential. The ROS level of oocytes is downregulated by HSYC (P < 0.01) and the percentage of abnormal mitochondrial in ovaries of the TR4 group was also significantly declined compared to the R4 group (P < 0.05); the most TUNEL-positive cells proportion was detected in the R4 group; nevertheless, HSYC effectively attenuated this detrimental effect (P < 0.05). The mRNA and protein expressions of JNK and P53 in ovary tissues were reduced in the TR4 group while these genes were upregulated by repeated superovulation (P < 0.05).

Conclusions

HSYC exerted promising effects on promoting the diminished ovarian reserve and decreased oocyte quality induced by both aging and consecutive ovarian superovulation, potentially via the ROS/JNK/p53 pathway.

Yin Huo Tang, a traditional Chinese herbal formula, relives ovariectomy and empty bottle stimulation-induced menopause-like symptoms in mice

BACKGROUND

Yin Huo Tang (YHT), a traditional Chinese herbal formula, is effectively used for the clinical treatment of menopause-like symptoms in China. This study aimed to investigate its efficacy on menopause-like symptoms in mice using behavioral tests and histopathological assessment, and to determine its possible mechanism of action based on network pharmacology.

METHODS

Liquid chromatography-mass spectrometry (LC-MS) technology was used to identify the potential active ingredients of YHT. In mice, menopause-like symptoms were induced by combination of bilateral ovariectomy and empty bottle stimulation. The mice were then treated with the YHT aqueous extract for three weeks. Behavior, sleep state, body weight, organ index, and histomorphology were analyzed separately. Additionally, network pharmacology and molecular docking were used to predict the mechanisms underlying the action of YHT. Finally, serum estradiol was quantified to preliminarily verify the results of network pharmacology.

RESULTS

YHT not only improved the behavior of mice (attack and explore behavior reduced; modify behavior increased) but also ameliorated the sleep state (sleep time increased and incubation time reduced). YHT reduced body weight, increased uterine weight, and improved the histomorphology of some organs. Network pharmacology and molecular docking analyses revealed that the estrogen signaling pathway might play a key role in attenuating menopause-like symptoms. Furthermore, YHT treatment reversed the reduction in serum estradiol levels.

CONCLUSIONS

YHT alleviates menopause-like symptoms in a mouse model, providing a rationale for using it as a potential therapeutic strategy.

Astragalin Protects against Spinal Cord Ischemia Reperfusion Injury through Attenuating Oxidative Stress-Induced Necroptosis

Spinal cord ischemia/reperfusion (SCI/R) injury is a devastating complication usually occurring after thoracoabdominal aortic surgery. However, it remains unsatisfactory for its intervention by using pharmacological strategies. Oxidative stress is a main pharmacological process involved in SCI/R, which will elicit downstream programmed cell death such as the novel defined necroptosis. Astragalin is a bioactive natural flavonoid with a wide spectrum of pharmacological activities. Herein, we firstly evaluated the effect of astragalin to oxidative stress as well as the possible downstream necroptosis after SCI/R in mice. Our results demonstrated that astragalin improves the ethological score and histopathological deterioration of SCI/R mice. Astragalin mitigates oxidative stress and ameliorates inflammation after SCI/R. Astragalin blocks necroptosis induced by SCI/R. That is, the amelioration of astragalin to the motoneuron injury and histopathological changes. Indicators of oxidative stress, inflammation, and necroptosis after SCI/R were significantly blocked. Summarily, we firstly illustrated the protection of astragalin against SCI/R through its blockage to the necroptosis at downstream of oxidative stress.

Human BM-MSC secretome enhances human granulosa cell proliferation and steroidogenesis and restores ovarian function in primary ovarian insufficiency mouse model

Primary ovarian insufficiency (POI) is defined as the loss of ovarian function before 40 years of age. It clinically manifests as amenorrhea, infertility, and signs of estrogen insufficiency. POI is frequently induced by chemotherapy. Gonadotoxic chemotherapy reagents damage granulosa cells, which are essential for follicular function and development. Our recently published studies demonstrated that intraovarian transplantation of human mesenchymal stem cells (hMSCs) can restore fertility in a chemotherapy-induced POI mouse model. However, the regenerative mechanism underlying the hMSC effect in POI mice is not fully understood. Here, we report that the hMSC secretome increased the proliferation of human granulosa cells (HGrC1). We showed by FACS analysis that treatment of HGrC1 cells with hMSC-conditioned media (hMSC CM) stimulates cellular proliferation. We also demonstrated that the expression of steroidogenic enzymes involved in the production of estrogen, CYP19A1 and StAR, are significantly elevated in hMSC CM-treated HGrC1 cells. Our data suggest that hMSC CM stimulates granulosa cell proliferation and function, which may explain the therapeutic effect of hMSCs in our chemotherapy-induced POI animal model. Our findings indicate that the hMSC secretome may be a novel treatment approach for restoring granulosa cell and ovarian function in patients with POI.

Administration of mulberry leaves maintains pancreatic β-cell mass in obese/type 2 diabetes mellitus mouse model

BACKGROUND

Type 2 diabetes mellitus is characterized by insulin resistance and pancreatic β-cell dysfunction. A decrease in β-cell mass, which occurs during the progression of Type 2 diabetes mellitus, contributes to impaired insulin secretion. Mulberry leaves contain various nutritional components that exert anti-diabetic and anti-atherogenic effects. The present study analyzed the effects of mulberry leaf intake on pancreatic β-cells to clarify the mechanisms underlying its anti-diabetic function.

METHODS

Mulberry leaves (Morus alba L.) were dried at 180 °C for 8 s in a hot-air mill and fed to obesity/Type 2 diabetes mellitus db/db mouse models at 5% (w/w) as part of a normal diet from 7 to 10, 15, or 20 weeks of age. An intraperitoneal glucose tolerance test was then performed on the mice. To evaluate the β-cell mass, the pancreas was subjected to immunohistological analysis with an anti-insulin antibody. A TUNEL assay and immunohistological analysis with a proliferation marker was also performed. Expression levels of endoplasmic reticulum stress-responsible genes and proliferation markers were assessed by quantitative RT-PCR.

RESULTS

Intake of mulberry leaves maintained the β-cell function of db/db mice. Moreover, oral administration of mulberry leaves significantly decreased cell death by reducing endoplasmic reticulum stress in the pancreas. Mulberry leaves significantly increased proliferation of β-cells and the expression of pancreatic duodenal homeobox1 mRNA in the pancreas.

CONCLUSION

Considered together, these results indicate that dietary mulberry leaf administration can maintain insulin levels and pancreatic β-cell mass, at least in part, by suppressing endoplasmic reticulum stress in Type 2 diabetes mellitus mouse models.

Effect of oral Utrogestan in comparison with Cetrotide on preventing luteinizing hormone surge in IVF cycles: A randomized controlled trial

Background

Oral progesterone is recommended as an alternative to gonadotropin-releasing hormone (GnRH) agonists and antagonists to prevent luteinizing hormone (LH) surge in assisted reproductive technology (ART) cycles. However, there are little data regarding its use.

Objective

We aimed to compare the effect of oral Utrogestan and Cetrotide (a GnRH antagonist) on preventing LH surge in ART cycles.

Materials and Methods

In this randomized clinical trial, 100 infertile women undergoing ART who received recombinant follicle-stimulating hormone (FSH) at 150-225 IU/day were randomly assigned to receive either Utrogestan 100 mg twice a day (case group) or GnRH antagonist protocol (control group) from cycle day 3 until the trigger day. Triggering was performed with 10,000 IU hCG) when there were at least three mature follicles. Viable embryos were cryopreserved for transfer in the next cycle for both groups. The number of oocytes retrieved and transferred embryos were compared between groups.

Results

The case group had significantly higher progesterone levels on triggering day, more follicles of >14 mm with higher maturity, and more oocytes retrieved with a higher rate of embryos transferred. A small increase in the pregnancy rate was observed in the case group, with no significant between-group differences. The most important result was the lack of premature LH surge in either group upon serum LH assessment on the triggering day.

Conclusion

Utrogestan is an alternative treatment that could reduce the LH surge rate and increase the ART outcomes including the number of oocytes retrieved and transferred embryos compared with GnRH agonists and antagonists

Genistein protects ovarian granulosa cells from oxidative stress via cAMP-PKA signaling

Genistein is an isoflavone that has estrogen (E₂ )-like activity and is beneficial for follicular development, but little is known regarding its function in oxidative stress (OS)-mediated granulosa cell (GC) injury. Here, we found that after exposure to H₂ O₂ , Genistein weakened the elevated levels of intracellular reactive oxygen species (ROS) and malondialdehyde (MDA), which were regarded as the biomarkers for OS, and rescued glutathione (GSH) content and GSH/GSSG ratio accompanying with a simultaneous increase in cyclic adenosine monophosphate (cAMP) level, whereas addition of protein kinase A (PKA) inhibitor H89 impeded the effects of Genistein on the levels of ROS and MDA. Further analysis evidenced that Genistein enhanced the activities of antioxidant enzymes superoxide dismutase (SOD), GSH-peroxidase (GSH-Px), and catalase (CAT) in H₂ O₂ -treated GCs, but this enhancement was attenuated by H89. Under OS, Genistein improved cell viability and lessened the apoptotic rate of GCs along with a reduction in the activity of Casp3 and levels of Bax and Bad messenger RNA (mRNA), while H89 reversed the above effects. Moreover, Genistein treatment caused an obvious elevation in mitochondrial membrane potential (MMP) followed by a decline in the levels of intracellular mitochondrial superoxide, but H89 inhibited the regulation of Genistein on MMP and mitochondrial superoxide. Supplementation of Genistein promoted the secretion of E₂ and increased the expression of Star and Cyp19a1 mRNA, whereas suppressed the level of progesterone (P₄ ) accompanied with a decline in the level of Hsd3b1 mRNA expression. H89 blocked the regulation of Genistein on the secretion of E₂ and P₄ , and alleviated the ascending of Star and Cyp19a1 elicited by Genistein. Collectively, Genistein protects GCs from OS via cAMP-PKA signaling.

A kaempferol-3-O-β-d-glucoside, intervention effect of astragalin on estradiol metabolism

Kaempherol-3-O-β-d-glucoside, known as astragalin, is one of flavonoids found in a variety of plants including Cuscuta australis R.Br. In recent studies, astragalin possess many biological functions. Although astragalin is formed by linking glucose to kaempherol, its biological activity is not the same as kaempferol. In vivo, 17 β-estradiol (E2) is hydroxylated by cytochrome P450 (CYP) 1B1 to form 4-hydroxy-E2 (4-OH-E2). This metabolite 4-OH-E2 is highly expressed in tumor tissues and has a strong tumorigenic effect. In this paper, the inhibition of astragalin and kaempferol on the activity of cytochrome 1B1 catalyzing estradiol to form 4-hydroxy-estradiol was studied, and the structure-activity relationship between astragalin and kaempferol due to their structural differences was discussed. This study showed that astragalin could inhibit the activity of CYP1B1. The inhibitory effect of astragalin (IC50 5.36 ± 1.13 μM) was weaker than kaempferol (IC50 0.45 ± 0.11 μM). For astragalin, Ki and Vmax values were 4.061 ± 0.737 μM and 1.457 pmol/μg protein/min, while for kaempferol, Ki and Vmax values were 2.631 ± 0.381 μM protein/min and 1.023 ± 0.231 pmol/μg. By kinetic analysis, astragalin and kaempferol were all mixed inhibition, indicating that although astragalin is formed by linking glucose to kaempherol, its inhibitory mechanism on CYP1B1 remained unchanged, and still belonged to a mixed inhibition. The data indicated that astragalin has been able to inhibit the metabolism of estradiol into the carcinogenic metabolite 4-hydroxyl-estradiol in vivo and illustrated an anti-tumor mechanism of astragalin. This study helps to reveal the structure-activity relationship between CYP1B1 activity and its inhibitors.

The Mulberry (Morus alba L.) Fruit-A Review of Characteristic Components and Health Benefits

Mulberry (Morus alba L.) fruit has a high yield in one fruiting season in many countries, especially in Asia, and a long history of use as an edible fruit and traditional medicine. A great diversity of nutritive compounds such as fatty acids, amino acids, vitamins, minerals, and bioactive compounds, including anthocyanins, rutin, quercetin, chlorogenic acid, and polysaccharides have been found in mulberry fruit depending on the cultivars and maturity stages. Furthermore, the extracts and active components of mulberry fruit have demonstrated numerous biological activities, including antioxidant, neuroprotective, antiatherosclerosis, immunomodulative, antitumor, antihyperglycemic, and hypolipidemic activities in in vitro and in vivo studies, and they have received increasing interest from researchers and pharmaceutical companies. Although some mechanistic studies further substantiate these potential health benefits of mulberry fruit, a need exists to make a better understanding of the roles of these compounds in traditional medicine and the diet. This review provides recent findings regarding the chemical constituents and biological activities of mulberry fruit, which may be useful for stimulating deep research of mulberry fruit and for predicting their uses as important and safe contributors to benefit human health.

Zinc finger gene 217 (ZNF217) Promoted Ovarian Hyperstimulation Syndrome (OHSS) through Regulating E2 Synthesis and Inhibiting Thrombospondin-1 (TSP-1)

Zinc finger gene 217 (ZNF217) is a candidate gene of polycystic ovary syndrome (PCOS) which is vulnerable to ovarian hyperstimulation syndrome (OHSS). However, the relationship between ZNF217 and OHSS is largely unknown. Our study demonstrated that ZNF217 was mainly distributed in the granulosa cells of rat ovary. Significantly higher expression of ovarian ZNF217 was detected in OHSS rats, being consistent with serum 17β-estradiol concentration and ovarian aromatase. Moreover, OHSS rats also showed decreased ovarian TSP-1 mRNA, an acknowledged VEGF signaling suppressor. The same changes were detected in human granulosa cells and follicular fluid. Thus, the increased ZNF217 and decreased TSP-1 may participate in OHSS onset. In vitro experiment revealed that ZNF217 positively regulated E₂ synthesis through promoting cAMP response element binding protein (CREB) and thereby CYP19A1 in KGN cells. Furthermore, ZNF217 negatively regulated TSP-1 in KGN cells while TSP-1 promoted claudin1 and inhibited nitric oxide (NO) in HUVECs and HAECs. Both of claudin1 and NO are responsible for the regulation of vascular permeability (VP). Therefore, we demonstrated that ZNF217 contributed to OHSS onset through promoting E₂ synthesis and the increase of VP. Moreover, the increased ZNF217 and decreased TSP-1 provided new targets for the prevention or treatment of OHSS in the future.