Chitosan oligosaccharide improves ovarian granulosa cells inflammation and oxidative stress in patients with polycystic ovary syndrome

Decoding the Lipid-POI connection: The mediating role of inflammatory factors

POI is a highly heterogeneous, multifactorial condition, and dysregulated lipid metabolism has been implicated in its inflammatory pathogenesis This study is the first to systematically investigate causal relationships between 179 lipid species, 91 inflammatory factors, and POI using Two-Sample Mendelian Randomization (TSMR) and Multivariable Mendelian Randomization (MVMR). By integrating lipidomics and inflammatories data with POI from Genome-wide association study (GWAS) and FinnGen, we identified 18 causally significant lipids, including risk-elevating phosphatidylcholines and sphingomyelins, and protective triglycerides. Methodologically, we innovatively applied Bayesian Weighted Mendelian Randomization (BWMR) to confirm the robustness of causal estimates, addressing limitations of conventional MR in pleiotropy-prone metabolic networks. Biologically, we discovered IL-10 mediates 7.02-9.03 % of the effects of sphingomyelin (d40:2) and (d42:2) on POI, reconciling lipid-driven inflammation with ovarian aging-a mechanism previously unreported. Sensitivity analyses confirmed no horizontal pleiotropy (p > 0.05). This work establishes three advances: (1) First MR evidence linking specific lipid subclasses (not just broad categories) to POI; (2) Identification of IL-10 as a novel inflammatory mediator bridging sphingolipids and POI pathogenesis; (3) A validated framework combining MVMR and mediation analysis to disentangle direct/indirect effects in reproductive aging. Our findings provide clinically actionable insights: IL-10 emerge as potential biomarkers, while triglycerides highlight dietary/therapeutic targets. This mechanistic clarity advances POI research beyond prior observational associations into causal biology.

Multiomics and Systematic Analyses Reveal the Roles of Hemoglobin and the HIF-1 Pathway in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) affects reproductive and cardiometabolic health, yet its pathogenesis remains unclear. Emerging evidence links hemoglobin levels to metabolic disorders, suggesting a potential role in PCOS development. Here, we integrated a large-scale cohort study, Mendelian randomization (A genetic tool to infer causal relationships), bioinformatics analyses, and in vitro experiments to investigate the relationship between hemoglobin levels and PCOS. In a cohort of 20 602 women, each 10 g L-1 elevation in hemoglobin levels is associated with 22% higher odds of PCOS (adjusted odds ratio: 1.22, 95% confidence interval: 1.15-1.29, P < 0.001) and PCOS manifestations, particularly hyperandrogenism. Mendelian randomization analysis confirms that higher hemoglobin levels are associated with increased PCOS risk and elevated testosterone levels. The hypoxia-inducible factor 1 (HIF-1) pathway is enriched, identifying three testosterone-associated genes (nuclear factor kappa B (NFKB1), insulin receptor (INSR), protein kinase C alpha. Colocalization and druggability analysis supports shared genetic regions and confirmed these genes as druggable targets. Upregulation of NFKB1 and INSR are confirmed in both blood and ovarian granulosa cells of PCOS patients. The findings demonstrate that higher-end normal hemoglobin levels are associated with increased PCOS risk, potentially through a mechanism of elevating testosterone levels involving the HIF-1 pathway.

Development of a dual-responsive injectable GelMA/F127DA hydrogel for enhanced cartilage regeneration in osteoarthritis: Harnessing MMP-triggered and mechanical stress-induced release of therapeutic agents

Osteoarthritis (OA) presents a significant challenge in clinical settings due to the limited self-renewal capability of cartilage tissue. To address this, engineered biomaterials employing biomimetic strategies have been developed to modulate and enhance cell-microenvironment interactions, facilitating cartilage regeneration. Nonetheless, excessive mechanical stress on joint structures can induce inflammatory responses, thereby impeding the process of cartilage repair. In this study, we focus on the OA microenvironment, characterized by the overexpression of matrix metalloproteinases (MMPs), and the mechanical stimuli due to joint movement. We engineered a dual-responsive injectable hydrogel: a blend of MMP-responsive, thermo-sensitive GelMA and mechanically robust, reverse thermo-sensitive F127DA. This hydrogel was designed to deliver TGF-β and KGN in a controlled manner via simple temperature modulation. The hydrophilic properties of GelMA and the hydrophobic nature of F127DA allow for efficient intra-articular delivery of diverse drug types, optimizing their therapeutic effects. Photocrosslinking the hydrogel in situ effectively seals cartilage defects and prevents further degradation. The overexpressed MMP in the OA environment triggers the release of TGF-β, recruiting bone marrow-derived stem cells (BMSCs), while mechanical pressure from joint movements releases KGN, promoting chondrogenic differentiation and mitigating inflammation. In summary, our injectable hydrogel, responsive to both the OA microenvironment and mechanical stress, shows promise in enhancing cartilage regeneration in OA. This approach holds significant potential for advancing the field of OA cartilage tissue engineering.

Exploring the molecular mechanism of Dioscorea alata L. for the treatment of menstrual disorders using network pharmacology and molecular docking

Menstrual disorders (MDs), including premenstrual syndrome, amenorrhea, and dysmenorrhea, affect women globally. Dioscorea alata L., a traditional yam species, has been used medicinally, but its potential in treating MDs remains understudied. This study employs a network pharmacology approach to examine the effects of D. alata's secondary metabolites on MDs via multi-target mechanisms. Compounds were identified from literature and PubChem, while disease-related targets were gathered from GeneCards, DisGeNET, and CTD databases. Swiss target prediction was used to link compounds to targets. A protein-protein interaction (PPI) network was constructed using STRING, and Gene Ontology (GO) and KEGG enrichment analyses were conducted to predict functional pathways. Eighteen bioactive compounds and 120 therapeutic targets specific to MDs were identified. KEGG analysis revealed 20 significant pathways related to menstrual disturbances. Among the 120 targets, TNF α, PPARG, ESR1, and AKT1 were highlighted as key therapeutic targets. Molecular docking showed strong interactions between Daidzein and ESR1, Diosgenin and TNF α, Alatanin and AKT1, and PPARG. The findings suggest that D. alata's bioactive compounds, such as Diosgenin, Daidzein, Genistin, Cycloartane, and Alatanin, could modulate pathways involved in ovarian follicle formation, hormone regulation, estrogen receptor signaling, and the stress-activated MAP kinase pathway. This study provides new insights into the multi-target potential of D. alata for treating menstrual disorders, supporting further investigation and therapeutic development.

Transcriptomic analysis of the effects exerted by curcumin on dihydrotestosterone-induced ovarian granulosa cells

Purpose

Hyperandrogenism is a leading cause of developmental retardation in ovarian granulosa cells. Previous studies have indicated that curcumin significantly improves follicular dysplasia, a characteristic of the polycystic ovary syndrome. Our purpose was to explore the signaling pathways which enable curcumin to protect the development of hyperandrogen-induced granulosa cells.

Methods

Ovarian granulosa cells treated with or without curcumin at different dihydrotestosterone (DHT) levels, were screened for cell viability, reactive oxygen species production, and apoptosis. RNA sequencing (transcriptome sequencing) was used to determine global gene expression in DHT-induced granulosa cells treated with curcumin.

Results

24 hours of combined curcumin and DHT treatment inhibited granulosa cell viability in a dose-dependent manner. Curcumin upregulated estrogen synthesis-related enzymes, downregulated lipid metabolism-related genes and the glucuronic acid process, inhibited androgen receptor (AR) activity, significantly improved cell viability, and corrected granulosa cell development. Gene set enrichment and genome transcriptome pathway analyses revealed the potential role played by curcumin in protecting granulosa cell development.

Conclusion

High androgen levels may disrupt steroid hormone synthesis and lipid metabolism pathways associated with granulosa cell development, thereby activating AR and inhibiting estrogen biosynthesis. Curcumin restores granulosa cell development by correcting abnormal steroid gene expression and disordered lipid fatty acid metabolism.

Correlation of GLUT4, LEPR , and TNF-a with endometrial receptivity in women with polycystic ovarian syndrome-induced infertility

Background

To analyze the correlation of glucose transporter 4 (GLUT4), leptin receptor (LEPR), and tumour necrosis factor-a (TNF-α) with endometrial receptivity (ER) in patients with polycystic ovarian syndrome (PCOS)induced infertility to provide clinical evidence for future diagnosis and treatment of PCOS-induced infertility.

Methods

We prospectively enrolled 109 study subjects admitted to The Second Hospital Affiliated of Shandong University of Traditional Chinese Medicine from June 2020 to August 2023, including 42 patients with PCOS-induced infertility (research group), 35 nonpregnant patients with simple PCOS (control group), and 32 nonpregnant healthy women (normal group). GLUT4, LEPR, and TNF-α levels in the peripheral blood were detected in all participants, and their diagnostic value for PCOS in healthy women and PCOS-induced infertility in PCOS patients was analyzed. In addition, the endometrial thickness and endometrial blood flow pulsation index (PI) and resistance index (RI) of patients in the research group were measured. Furthermore, the correlation of GLUT4, LEPR, and TNF-α with ER was discussed.

Results

GLUT4 was lower in the research group compared with the control and normal groups, while LEPR and TNF-α were higher (P<0.05); the control group showed lower GLUT4 and higher LEPR and TNF-α levels than the normal group (P<0.05). The diagnostic sensitivity and specificity of GLUT4, LEPR, and TNF-α combined assay for PCOSinduced infertility in PCOS women were 88.57% and 75.00%, respectively, and those for PCOS in healthy women were 78.57% and 60.00%, respectively (P<0.05). In the research group, GLUT4 was positively correlated with endometrial thickness and negatively linked to RI and PI. At the same time, LEPR and TNF-α were negatively associated with endometrial thickness and positively correlated with RI and PI (P<0.05).

Conclusions

GLUT4, LEPR, and TNF-α are closely related to ER in patients with PCOS-induced infertility, and their combined detection can effectively evaluate the occurrence of PCOS and PCOS-induced infertility.

Oxidative stress and energy metabolism abnormalities in polycystic ovary syndrome: from mechanisms to therapeutic strategies

Polycystic ovary syndrome (PCOS), as a common endocrine and metabolic disorder, is often regarded as a primary cause of anovulatory infertility in women. The pathogenesis of PCOS is complex and influenced by multiple factors. Emerging evidence highlights that energy metabolism dysfunction and oxidative stress in granulosa cells (GCs) are pivotal contributors to aberrant follicular development and impaired fertility in PCOS patients. Mitochondrial dysfunction, increased oxidative stress, and disrupted glucose metabolism are frequently observed in individuals with PCOS, collectively leading to compromised oocyte quality. This review delves into the mechanisms linking oxidative stress and energy metabolism abnormalities in PCOS, analyzing their adverse effects on reproductive function. Furthermore, potential therapeutic strategies to mitigate oxidative stress and metabolic disturbances are proposed, providing a theoretical basis for advancing clinical management of PCOS.

Chitosan-Based Hydrogels as Antibacterial/Antioxidant/Anti-Inflammation Multifunctional Dressings for Chronic Wound Healing

Due to repeated microbial infection, persistent inflammation, excessive oxidative stress, and cell dysfunction, chronic wounds are difficult to heal, posing a serious threat to public health. Therefore, developing multifunctional wound dressings that can regulate the complex microenvironment of chronic wounds and enhance cellular function holds great significance. Recently, chitosan has emerged as a promising biopolymer for wound healing due to its excellent biocompatibility, biodegradability, and versatile bioactivity. The aim of this review is to provide a comprehensive understanding of the mechanisms of delayed chronic wound healing and discuss the healing-promoting properties of chitosan and its derivatives, such as good biocompatibility, antibacterial activity, hemostatic capacity, and the ability to promote tissue regeneration. On this basis, the potential applications of chitosan-based hydrogels are summarized in chronic wound healing, including providing a suitable microenvironment, eliminating bacterial infections, promoting hemostasis, inhibiting chronic inflammation, alleviating oxidative stress, and promoting tissue regeneration. In addition, the concerns and perspectives for the clinical application of chitosan-based hydrogels are also discussed.

Identification and validation of novel genes related to immune microenvironment in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is one of the most complicated chronic inflammatory diseases in women of reproductive age and is one of the primary factors responsible for infertility. There is substantial dispute relating to the pathophysiology of PCOS. Consequently, there is a critical need for further research to identify the factors underlying the pathophysiology of PCOS. Three transcriptome profiles of granulosa cells from patients with PCOS and normal controls were obtained from the gene expression integration database. We also obtained relevant microarrays of granulocytes prepared from PCOS patients and normal controls from the gene expression integration database. Then, we used the R package to perform correlations and identify differences between PCOS and normal controls with regard to immune infiltrating cells and functionality. Subsequently, intersecting genes were identified and risk models were constructed. Finally, the results were validated by enzyme linked immunosorbent assay and real-time PCR. We identified 8 genes related to cuproptosis (SLC31A1, PDHB, PDHA1, DLST, DLD, DLAT, DBT, and ATP7A) and 5 genes related to m7G (SNUPN, NUDT16, GEMIN5, DCPS, and EIF4E3) that were associated with immune infiltration. Furthermore, the expression levels of DLAT (P = .049) and NUDT16 (P = .024) differed significantly between the PCOS patients and normal controls, as revealed by multifactorial analysis. Both DLAT and NUDT16 were negatively correlated with immune cell expression and function and expression levels were significantly lower in the PCOS group. Finally, real-time PCR and enzyme linked immunosorbent assay demonstrated that the expression levels of DLAT and NUDT16 were significantly reduced in the granulosa cells of PCOS patients. In conclusion, our findings shed fresh light on the roles of immune infiltration, cuproptosis, and m7G alternations in PCOS. We also provide a reliable biomarker for the pathological classification of PCOS patients.

Chitosan oligosaccharides alleviate macrophage pyroptosis and protect sepsis mice via activating the Nrf2/GPX4 pathway

In the process of sepsis, excessive occurrence of pyroptosis, a form of programmed cell death acting as a defense mechanism against pathogens, can disrupt immune responses, thus leading to tissue damage and organ dysfunction. Chitosan oligosaccharide (COS), derived from chitosan degradation, has demonstrated diverse beneficial effects. However, its impact on sepsis-induced pyroptosis remains unexplored. In the present study, ATP/LPS was utilized to induce canonical-pyroptosis in THP-1 cells, while bacterial outer membrane vesicles (OMV) were employed to trigger non-canonical pyroptosis in RAW264.7 cells. Our results revealed a dose-dependent effect of COS on both types of pyroptosis. This was evidenced by a reduction in the expression of pro-inflammatory cytokines, as well as crucial regulatory proteins involved in pyroptosis. In addition, COS inhibited the cleavage of caspase-1 and GSDMD, and reduced ASC oligomerization. The underlying mechanism revealed that COS acts an antioxidant, reducing the release of pyroptosis-induced ROS and malondialdehyde (MDA) by upregulation the expression and promoting the nuclear translocation of nuclear factor erythroid-2-related factor 2 (Nrf2), which led to an elevation of glutathione peroxidase 4 (GPX4) and superoxide dismutase (SOD). Notably, the actions of COS were completely reversed by the Nrf2 inhibitor. Consequently, COS intervention increased the survival rate of sepsis.

Chitosan alleviates ovarian aging by enhancing macrophage phagocyte-mediated tissue homeostasis

BACKGROUND

Age-related changes in the ovarian microenvironment are linked to impaired fertility in women. Macrophages play important roles in ovarian tissue homeostasis and immune surveillance. However, the impact of aging on ovarian macrophage function and ovarian homeostasis remains poorly understood.

METHODS

Senescence-associated beta-galactosidase staining, immunohistochemistry, and TUNEL staining were used to assess senescence and apoptosis, respectively. Flow cytometry was employed to evaluate mitochondrial membrane potential (MMP) and apoptosis in granulosa cells lines (KGN), and macrophages phagocytosis. After a 2-month treatment with low molecular weight Chitosan (LMWC), ovarian tissues from mice were collected for comprehensive analysis.

RESULTS

Compared with the liver and uterus, the ovary displayed accelerated aging in an age-dependent manner, which was accompanied by elevated levels of inflammatory factors and apoptotic cells, and impaired macrophage phagocytic activity. The aged KGN cells exhibited elevated reactive oxygen species (ROS) and apoptotic levels alongside decreased MMP. H2O2-induced aging macrophages showed reduced phagocytosis function. Moreover, there were excessive aging macrophages with impaired phagocytosis in the follicular fluid of patients with diminished ovarian reserve (DOR). Notably, LMWC administration alleviated ovarian aging by enhancing macrophage phagocytosis and promoting tissue homeostasis.

CONCLUSIONS

Aging ovarian is characterized by an accumulation of aging and apoptotic granulosa cells, an inflammatory response and macrophage phagocytosis dysfunction. In turn, impaired phagocytosis of macrophage contributes to insufficient clearance of aging and apoptotic granulosa cells and the increased risk of DOR. Additionally, LMWC emerges as a potential therapeutic strategy for age-related ovarian dysfunction.

The role of the autonomic nervous system in polycystic ovary syndrome

This article reviewed the relationship between the autonomic nervous system and the development of polycystic ovary syndrome (PCOS). PCOS is the most common reproductive endocrine disorder among women of reproductive age. Its primary characteristics include persistent anovulation, hyperandrogenism, and polycystic ovarian morphology, often accompanied by disturbances in glucose and lipid metabolism. The body's functions are regulated by the autonomic nervous system, which consists mainly of the sympathetic and parasympathetic nervous systems. The autonomic nervous system helps maintain homeostasis in the body. Research indicates that ovarian function in mammals is under autonomic neural control. The ovaries receive central nervous system information through the ovarian plexus nerves and the superior ovarian nerves. Neurotransmitters mediate neural function, with acetylcholine and norepinephrine being the predominant autonomic neurotransmitters. They influence the secretion of ovarian steroids and follicular development. In animal experiments, estrogen, androgens, and stress-induced rat models have been used to explore the relationship between PCOS and the autonomic nervous system. Results have shown that the activation of the autonomic nervous system contributes to the development of PCOS in rat. In clinical practice, assessments of autonomic nervous system function in PCOS patients have been gradually employed. These assessments include heart rate variability testing, measurement of muscle sympathetic nerve activity, skin sympathetic response testing, and post-exercise heart rate recovery evaluation. PCOS patients exhibit autonomic nervous system dysfunction, characterized by increased sympathetic nervous system activity and decreased vagal nerve activity. Abnormal metabolic indicators in PCOS women can also impact autonomic nervous system activity. Clinical studies have shown that various effective methods for managing PCOS regulate patients' autonomic nervous system activity during the treatment process. This suggests that improving autonomic nervous system activity may be an effective approach in treating PCOS.

Intra-ovarian inflammatory states and their associations with embryo quality in normal-BMI PCOS patients undergoing IVF treatment

BACKGROUND

Polycystic ovary syndrome (PCOS) is the main cause of anovulatory infertility in women of reproductive age, and low-grade chronic inflammation plays a key role in the occurrence and development of PCOS. However, obesity, as a likely confounding factor, can affect the inflammatory state of PCOS patients.

OBJECTIVE

The aim of this study was to comprehensively investigate intra-ovarian inflammatory states and their impact on embryo quality in PCOS patients with a normal BMI undergoing IVF treatment.

METHODS

DIA-mass spectrometry-based proteomics and bioinformatic analysis were combined to comprehensively profile the protein expression of granulosa cells (GCs) from 5 normal-BMI PCOS patients and 5 controls. Thirty-four cytokines were further systematically detected in follicular fluid (FF) from 32 age- and BMI-matched normal-BMI patients using Luminex liquid chip suspension technology. Next, the differentially expressed cytokines were evaluated by enzyme-linked immunosorbent assay (ELISA) in 24 newly recruited subjects, and the relationship between these cytokines and embryo quality in PCOS patients was analysed. Finally, these cytokine levels were compared and evaluated in PCOS patients with different androgen levels.

RESULTS

Proteomic analysis showed that the suppression of substance metabolism and steroid biosynthesis, more interestingly, resulted in an enhanced immune and inflammatory response in the GCs of normal-BMI PCOS patients and prompted the involvement of cytokines in this process. Luminex analysis further showed that FF macrophage inflammatory protein-1 beta (MIP-1β) and stromal cell-derived factor-1 alpha (SDF-1α) levels were significantly increased in normal-BMI PCOS patients compared to controls (P = 0.005; P = 0.035, respectively), and the ELISA results were consistent with these findings. Besides, FF MIP-1β showed an inverse correlation with the number of D3 good-quality embryos and the good-quality blastocyst rate in patients with PCOS (P = 0.006; P = 0.003, respectively), which remained significant after correction for multiple comparisons. Moreover, SDF-1α levels had no relationship with embryo development in PCOS patients. Additionally, SDF-1α levels were significantly lower in PCOS patients with high androgen levels than in controls (P = 0.031).

CONCLUSIONS

Local ovarian inflammation was present in normal-BMI PCOS patients, affecting follicular development, and FF MIP-1β may be a potential biomarker associated with embryo quality in normal-BMI PCOS patients.

The delaying effect of Qingxin Zishen decoction on ovarian aging: Examining regulation of ovarian mitochondria apoptosis in aged rats

Ovarian aging is a significant challenge in gynecology, and there is currently no effective treatment for it. However, the medicinal agent Qingxin Zishen decoction (QZD) has shown potential in the treatment of ovarian dysfunction. The present study aimed to evaluate the mitochondrial apoptotic mechanism of delayed ovarian aging in QZD in aging rats. The healthy female Sprague-Dawley (SD) rats (n = 40, 350 ± 20 g) were randomly assigned to different dosage groups and 4-month-old SD rats (n = 10) were assigned to the control group. QZD groups were treated with QZD for four weeks, and ovarian tissues were extracted for mRNA and protein assays to examine the role of the apoptotic pathway in QZD. The results showed that QZD treatment for four weeks significantly increased the mRNA and protein expressions of the anti-apoptotic gene B-cell lymphoma 2 (Bcl-2) and Bcl-2/Bax ratio, as well as downregulated the pro-apoptotic genes Bax, caspase-3, and caspase-9. Moreover, QZD treatment effectively reduced the expression of cytochrome C (cyto-C) and apoptotic protease-activating factor 1 (Apaf-1), both of which are components of the intrinsic apoptotic pathway. These changes exhibited a dose-response manner. The findings suggest that QZD might have therapeutic potential in delaying ovarian mitochondrial function decline and in preventing and treating ovarian aging-related diseases by downregulating and upregulating the pro-apoptotic (Bax, caspase-3, caspase-9, cyto-C, Apaf-1) and anti-apoptotic (Bcl-2 and Bcl-2/Bax ratio) genes, respectively.

Bilirubin Concentration in Follicular Fluid Is Increased in Infertile Females, Correlates with Decreased Antioxidant Levels and Increased Nitric Oxide Metabolites, and Negatively Affects Outcome Measures of In Vitro Fertilization

In a previous study, we showed that various low-molecular-weight compounds in follicular fluid (FF) samples of control fertile females (CFF) have different concentrations compared to those found in FF of infertile females (IF), before and after their categorization into different subgroups, according to their clinical diagnosis of infertility. Using the same FF samples of this previous study, we here analyzed the FF concentrations of free and bound bilirubin and compared the results obtained in CFF, IF and the different subgroups of IF (endometriosis, EM, polycystic ovary syndrome, PCOS, age-related reduced ovarian reserve, AR-ROR, reduced ovarian reserve, ROR, genetic infertility, GI and unexplained infertility, UI). The results clearly indicated that CFF had lower values of free, bound and total bilirubin compared to the respective values measured in pooled IF. These differences were observed even when IF were categorized into EM, PCOS, AR-ROR, ROR, GI and UI, with EM and PCOS showing the highest values of free, bound and total bilirubin among the six subgroups. Using previous results of ascorbic acid, GSH and nitrite + nitrate measured in the same FF samples of the same FF donors, we found that total bilirubin in FF increased as a function of decreased values of ascorbic acid and GSH, and increased concentrations of nitrite + nitrate. The values of total bilirubin negatively correlated with the clinical parameters of fertilization procedures (number of retrieved oocytes, mature oocytes, fertilized oocytes, blastocysts, high-quality blastocysts) and with clinical pregnancies and birth rates. Bilirubin concentrations in FF were not linked to those found in serum samples of FF donors, thereby strongly suggesting that its over production was due to higher activity of heme oxygenase-1 (HO-1), the key enzyme responsible for bilirubin formation, in granulosa cells, or cumulus cells or oocytes of IF and ultimately leading to bilirubin accumulation in FF. Since increased activity of HO-1 is one of the main enzymatic intracellular mechanisms of defense towards external insults (oxidative/nitrosative stress, inflammation), and since we found correlations among bilirubin and oxidative/nitrosative stress in these FF samples, it may reasonably be supposed that bilirubin increase in FF of IF is the result of protracted exposures to the aforementioned insults evidently playing relevant roles in female infertility.

Immunity and reproduction protective effects of Chitosan Oligosaccharides in Cyclophosphamide/Busulfan-induced premature ovarian failure model mice

Introduction

Premature ovarian failure (POF) is a major cause of infertility among women of reproductive age. Unfortunately, there is no effective treatment available currently. Researchers have shown that immune disorders play a significant role in the development of POF. Moreover, growing evidence suggest that Chitosan Oligosaccharides (COS), which act as critical immunomodulators, may have a key role in preventing and treating a range of immune related reproductive diseases.

Methods

KM mice (6-8 weeks) received a single intraperitoneal injection of cyclophosphamide (CY, 120mg/kg) and busulfan (BUS, 30mg/kg) to establish POF model. After completing the COS pre-treatment or post-treatment procedures, peritoneal resident macrophages (PRMs) were collected for neutral erythrophagocytosis assay to detect phagocytic activity. The thymus, spleen and ovary tissues were collected and weighed to calculate the organ indexes. Hematoxylin-eosin (HE) staining was performed to observe the histopathologic structure of those organs. The serum levels of estrogen (E2) and progesterone (P) were measured via the enzyme-linked immunosorbent assay (ELISA). The expression levels of immune factors including interleukin 2 (IL-2), interleukin 4 (IL-4), and tumor necrosis factor α (TNF-α), as well as germ cell markers Mouse Vasa Homologue (MVH) and Fragilis in ovarian tissue, were analyzed by Western blotting and qRT-PCR. In addition, ovarian cell senescence via p53/p21/p16 signaling was also detected.

Results

The phagocytic function of PRMs and the structural integrity of thymus and spleen were preserved by COS treatment. The levels of certain immune factors in the ovaries of CY/BUS- induced POF mice were found to be altered, manifested as IL-2 and TNF-α experiencing a significant decline, and IL-4 presenting a notable increase. Both pre-treatment and post-treatment with COS were shown to be protective effects against the damage to ovarian structure caused by CY/BUS. Senescence-associated β-galactosidase (SA-β-Gal) staining results showed that COS prevents CY/BUS-induced ovarian cell senescence. Additionally, COS regulated estrogen and progesterone levels, enhanced follicular development, and blocked ovarian cellular p53/p21/p16 signaling which participating in cell senescence.

Conclusion

COS is a potent preventative and therapeutic medicine for premature ovarian failure by enhancing both the ovarian local and systemic immune response as well as inhibiting germ cell senescence.