Inflammation Triggered by Saturated Fat Ingestion Is Linked to Insulin Resistance and Hyperandrogenism in Polycystic Ovary Syndrome

Association of insulin resistance surrogates with live birth outcomes in women with polycystic ovary syndrome undergoing in vitro fertilization

BACKGROUND

Insulin resistance (IR) is a common pathophysiologic feature in patients with polycystic ovary syndrome (PCOS). However, there have been no studies investigating the association of IR surrogates with pregnancy outcomes in women with PCOS undergoing in vitro fertilization (IVF). Therefore, we explored the association between these factors among PCOS patients.

METHODS

We conducted a retrospective study that included patients with PCOS who underwent IVF at a university-affiliated hospital. Blood samples and physical examinations are collected at reproductive center on fasting in the morning of the 2nd to 4th day of the menstrual cycle prior to medication. We categorized participants into "Non-IR group" (HOMA-IR < 2.2) and "IR group" (HOMA-IR ≥ 2.2). The association of IR surrogates [triglyceride-glucose-body mass index (TyG-BMI), triglyceride-glucose (TyG) and homeostasis model assessment (HOMA-IR)] with IVF outcomes was evaluated by regression model analysis. Moreover, we also performed sensitivity analyses with stratification and interaction tests. The primary outcome variable was the live birth rate.

RESULTS

A total of 543 PCOS patients were finally included in the study. In all three regression models for the fresh embryo transfer (ET) cycles, all three IR surrogates showed stable negative correlations with live birth rate (in Model III: TyG-BMI OR = 0.99, 95% CI: 0.98 ~ 0.99; TyG OR = 0.47, 95% CI: 0.27 ~ 0.82; HOMA-IR OR = 0.84, 95% CI: 0.72 ~ 0.97; all P < 0.05), and this association was stable across all subgroups of the population (all P-interaction > 0.05). However, this relationship did not exist in frozen-thawed embryo transfer (FET) cycles. Furthermore, our study found that TyG-BMI was superior to TyG and HOMA-IR in predicting the rate of live birth in fresh ET cycles [TyG-BMI: 0.64 (95% CI: 0.58, 0.69) vs. TyG: 0.61 (95% CI: 0.55, 0.67) vs. HOMA-IR: 0.60 (95% CI: 0.55, 0.67)].

CONCLUSIONS

Our study revealed that the three IR surrogates (TyG-BMI, TyG and HOMA-IR) were negatively associated with the live birth rates in fresh ET cycles. However, this relationship did not exist in FET cycles. Furthermore, our study found that TyG-BMI was superior to TyG and HOMA-IR in predicting the rate of live birth in fresh ET cycles.

Adipose Tissue Plasticity: A Comprehensive Definition and Multidimensional Insight

Adipose tissue is composed of adipocytes, stromal vascular fraction, nerves, surrounding immune cells, and the extracellular matrix. Under various physiological or pathological conditions, adipose tissue shifts cellular composition, lipid storage, and organelle dynamics to respond to the stress; this remodeling is called "adipose tissue plasticity". Adipose tissue plasticity includes changes in the size, species, number, lipid storage capacity, and differentiation function of adipocytes, as well as alterations in the distribution and cellular composition of adipose tissue. This plasticity has a major role in growth, obesity, organismal protection, and internal environmental homeostasis. Moreover, certain thresholds exist for this plasticity with significant individualized differences. Here, we comprehensively elaborate on the specific connotation of adipose tissue plasticity and the relationship between this plasticity and the development of many diseases. Meanwhile, we summarize possible strategies for treating obesity in response to adipose tissue plasticity, intending to provide new insights into the dynamic changes in adipose tissue and contribute new ideas to relevant clinical problems.

Investigating the Role of Inflammatory Response in Polycystic Ovary Syndrome Using Integrated RNA-Seq Analysis

Background

An important factor in the pathogenesis of polycystic ovary syndrome (PCOS) is chronic low-grade inflammation. However, the exact pathophysiology of PCOS is currently unknown, which makes clinical diagnosis and the development of effective treatments more difficult. We aimed to investigate the role of the inflammatory response in initiating and progressing PCOS.

Methods

13 control granulosa cell samples and 15 granulosa cell samples from patients with PCOS were obtained from the GSE102293, GSE34526, and GSE5850 datasets. The gene set variation analysis (GSVA) method was used to calculate the inflammatory response score. Subsequently, the genes associated with inflammation in the hub were identified using differential expression analysis and weighted gene co-expression network analysis (WGCNA). The findings were confirmed by analysis of independent datasets and examination of clinical samples by qRT-PCR analysis. A consensus cluster analysis was conducted to categorize the PCOS samples into subtypes related to inflammation. Functional enrichment and analysis of immune cell infiltration were conducted to explore the potential mechanisms involved. Additionally, the CMap database was utilized to predict potential drugs, and the results were confirmed through molecular docking.

Results

During the training cohort analysis, we identified five distinct genes (TGFBR2, ICAM3, WIPF1, SLC11A1, and NCF2) that could serve as potential diagnostic markers for PCOS. The expression levels of these genes were confirmed through validation in both the test set and clinical samples. In training cohort, two distinct inflammatory patterns (C1 and C2) were identified, and the C2 subtype exhibited activated immune- and inflammation-related pathways. Esmolol was shown to have potential as a drug to treat PCOS and it showed good results for molecular binding at TGFBR2, ICAM3, WIPF1, SLC11A1, and NCF2 proteins.

Conclusion

Five diagnostic biomarkers and two inflammation-related molecular types associated with PCOS were identified, and esmolol was a potential drug for PCOS treatment. Our findings provided new diagnostic markers and potential small-molecule drugs for PCOS diagnosis and prevention.

Research hotspots of polycystic ovary syndrome and hyperandrogenism from 2008 to 2022: bibliometric analysis

BACKGROUND

Polycystic Ovary Syndrome (PCOS) is the most frequent endocrine disorder in female adults, and hyperandrogenism (HA) is the typical endocrine feature of PCOS. This study aims to investigate the trends and hotspots in the study of PCOS and HA.

METHODS

Literature on Web of Science Core Collection (WoSCC) from 2008 to 2022 was retrieved, and bibliometric analysis was conducted using VOSviewer and CiteSpace software.

RESULTS

A total of 2,404 papers were published in 575 journals by 10,121 authors from 2,434 institutions in 86 countries. The number of publications in this field is generally on the rise yearly. The US, China and Italy contributed almost half of the publications. Monash University had the highest number of publications, while the University of Adelaide had the highest average citations and the Karolinska Institute had the strongest cooperation with other institutions. Lergo RS contributed the most to the field of PCOS and HA. The research on PCOS and HA mainly focused on complications, adipose tissue, inflammation, granulosa cells, gene and receptor expression.

CONCLUSION

Different countries, institutions, and authors should facilitate cooperation and exchanges. This study will be helpful for better understanding the frontiers and hotspots in the areas of PCOS and HA.

Serum HMGB1 levels are independently associated with glucose clamp-derived measures of insulin resistance in women with PCOS

PURPOSE

PCOS is associated with low grade inflammation which could play a role in insulin resistance and ovarian dysfunction. Preliminary findings suggested that serum levels of HMGB1, a cytokine involved in inflammation, might be altered in women with PCOS. Primary aim of this study was to assess whether HMGB1 serum concentrations are associated with PCOS and with the state of insulin resistance of these women.

METHODS

Sixty women with PCOS, selected to have a similar proportion of subjects with altered or normal insulin sensitivity, and 29 healthy controls were studied. Serum HMGB1 levels were compared in subgroups of PCOS women and controls. In PCOS women, insulin sensitivity was assessed by the glucose clamp technique and HMGB1 was measured at baseline and after acute hyperinsulinemia.

RESULTS

HMGB1 levels were similar in women with PCOS and controls and no elements used for diagnosing PCOS were associated with serum HMGB1. However, HMGB1 concentrations were higher in insulin-resistant vs insulin-sensitive PCOS women (p = 0.017), and inversely associated with insulin-induced total and non-oxidative glucose metabolism. In both subgroups of PCOS women, serum HMBG1 levels significantly increased after acute hyperinsulinemia.

CONCLUSIONS

These data suggest that HMGB1 levels are not associated with PCOS per se, but with insulin resistance. Further research should establish the underlying nature of this relationship, and whether this protein might play a role in the metabolic complications of PCOS.

The overexpression of neurokinin B-neurokinin 3 receptor system exerts direct effects on the ovary under PCOS-like conditions to interfere with mitochondrial function

PROBLEM

The increased hypothalamic neurokinin B (NKB) level may contribute to the hyperactive LH pulse secretion in Polycystic ovary syndrome (PCOS). However, the expression and role of the neurokinin B-neurokinin 3 receptor (NKB-NK3R) system in the local ovarian tissue of PCOS have not been clarified. We constructed in vivo and in vitro models to elucidate the mechanism of the NKB-NK3R pathway in reproductive endocrine disorders of PCOS.

METHOD OF STUDY

The granulosa cell line-KGN cells were set in palmitic acid (PA) and dihydrotestosterone (DHT) to simulate the PCOS-like conditions. And we used the high-fat/high-glucose diet to build a PCOS-like mice model and neurokinin 3 receptor antagonist (NK3Ra) was administered to half of the mice. The expression of the NKB-NK3R system, mitochondrial functions, hormone levels, and inflammatory state was evaluated.

RESULTS

The PCOS-like stimulations induced the NKB-NK3R system and MAPK-ERK pathway overexpression in KGN cells, in an approximate dose and time-dependent manner. The NKB-NK3R system overactivated the MAPK-ERK pathway to increase NNT overexpression, disturb NADH/NADPH pools, aggravate the oxidation state, and decrease ATP production. With overexpression of the NKB-NK3R system in the local ovarian tissue, ovulatory dysfunction, progesterone deficiency, and pro-inflammatory states were apparent in PCOS-like mice. Antagonizing the receptor, NK3R, reversed the adverse reproductive endocrine phenotypes via improving mitochondrial dysfunction.

CONCLUSIONS

In addition to the central regulation, local ovarian overexpression of the NKB-NK3R system participated in the adverse reproductive endocrine phenotypes, supporting the therapeutic implications of NK3Ra for PCOS.

The Role of Nutrition on Meta-inflammation: Insights and Potential Targets in Communicable and Chronic Disease Management

PURPOSE OF REVIEW

Chronic low-grade inflammation may contribute to the onset and progression of communicable and chronic diseases. This review examined the effects and eventual mediation roles of different nutritional factors on inflammation.

RECENT FINDINGS

Potential nutritional compounds influencing inflammation processes include macro and micronutrients, bioactive molecules (polyphenols), specific food components, and culinary ingredients as well as standardized dietary patterns, eating habits, and chrononutrition features. Therefore, research in this field is still required, taking into account critical aspects of heterogeneity including type of population, minimum and maximum intakes and adverse effects, cooking methods, physiopathological status, and times of intervention. Moreover, the integrative analysis of traditional variables (age, sex, metabolic profile, clinical history, body phenotype, habitual dietary intake, physical activity levels, and lifestyle) together with individualized issues (genetic background, epigenetic signatures, microbiota composition, gene expression profiles, and metabolomic fingerprints) may contribute to the knowledge and prescription of more personalized treatments aimed to improving the precision medical management of inflammation as well as the design of anti-inflammatory diets in chronic and communicable diseases.

Sodium-glucose cotransporter 2 inhibitor ameliorates high fat diet-induced hypothalamic-pituitary-ovarian axis disorders

High-fat diet (HFD) consumption is known to be associated with ovulatory disorders among women of reproductive age. Previous studies in animal models suggest that HFD-induced microglia activation contributes to hypothalamic inflammation. This causes the dysfunction of the hypothalamic-pituitary-ovarian (HPO) axis, leading to subfertility. Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a novel class of lipid-soluble antidiabetic drugs that target primarily the early proximal tubules in kidney. Recent evidence revealed an additional expression site of SGLT2 in the central nervous system (CNS), indicating a promising role of SGLT2 inhibitors in the CNS. In type 2 diabetes patients and rodent models, SGLT2 inhibitors exhibit neuroprotective properties through reduction of oxidative stress, alleviation of cerebral atherosclerosis and suppression of microglia-induced neuroinflammation. Furthermore, clinical observations in patients with polycystic ovary syndrome (PCOS) demonstrated that SGLT2 inhibitors ameliorated patient anthropometric parameters, body composition and insulin resistance. Therefore, it is of importance to explore the central mechanism of SGLT2 inhibitors in the recovery of reproductive function in patients with PCOS and obesity. Here, we review the hypothalamic inflammatory mechanisms of HFD-induced microglial activation, with a focus on the clinical utility and possible mechanism of SGLT2 inhibitors in promoting reproductive fitness.

IL23 suppresses proliferation and promotes apoptosis of human granulosa-like tumor cell line KGN by targeting the androgen receptor signal pathway

Background: Polycystic ovary syndrome (PCOS) is associated with chronic low-grade inflammation. IL23 is a classic pro-inflammatory factor, which has been found that serum levels of IL23 were higher in patients with PCOS. However, the exact function of IL23 in regulating the pathogenesis of PCOS has not been elucidated. This study aimed to investigate the role of IL23 in the pathogenesis of PCOS and uncover the possible molecular mechanism. Methods: We investigated the role of IL23 in the proliferation, cell cycle progression and apoptosis of granulosa cells (GCs) using the human granulosa-like tumor cell line KGN. Results: IL23 suppressed the proliferation, arrested cell cycle progression, and increased apoptosis of KGN cells. We also found that IL23 decreases proliferation and promotes apoptosis in KGN cells is mediated by androgen receptor (AR) signaling. Conclusions: Our results demonstrated that IL23 suppressed cell proliferation and promoted apoptosis of KGN cells, which might provide new evidence for abnormal proliferation and apoptosis of GCs in PCOS.

The Role of Individually Selected Diets in Obese Women with PCOS-A Review

Polycystic ovarian syndrome (PCOS) is one of the most common heterogeneous endocrine and metabolic disorders in premenopausal women. It is a complex multifactorial disorder with strong epigenetic and environmental influences, including factors related to eating habits and lifestyle. There is a close relationship between obesity and PCOS. Weight gain and obesity are often clinical symptoms manifested by biochemical markers. Moreover, abdominal obesity in women with PCOS is involved in the development of inflammatory changes. A significant share of balanced therapies correcting the lifestyle of patients is suggested, e.g., with the implementation of appropriate diets to minimize exposure to inflammatory factors and prevent abnormal immune system stimulation. In the case of obese patients with PCOS, planning a diet program and supporting the motivation to change eating habits play an important role to lose weight and lower BMI. Probiotics/synbiotic supplementation may enhance weight loss during the diet program and additionally positively affect metabolic and inflammatory factors by improving the intestinal microbiome.

Anti-Inflammatory Diets in Fertility: An Evidence Review

Infertility is a global health concern affecting 48 million couples and 186 million individuals worldwide. Infertility creates a significant economic and social burden for couples who wish to conceive and has been associated with suboptimal lifestyle factors, including poor diet and physical inactivity. Modifying preconception nutrition to better adhere with Food-Based Dietary Guidelines (FBDGs) is a non-invasive and potentially effective means for improving fertility outcomes. While several dietary patterns have been associated with fertility outcomes, the mechanistic links between diet and infertility remain unclear. A key mechanism outlined in the literature relates to the adverse effects of inflammation on fertility, potentially contributing to irregular menstrual cyclicity, implantation failure, and other negative reproductive sequelae. Therefore, dietary interventions which act to reduce inflammation may improve fertility outcomes. This review consistently shows that adherence to anti-inflammatory diets such as the Mediterranean diet (specifically, increased intake of monounsaturated and n-3 polyunsaturated fatty acids, flavonoids, and reduced intake of red and processed meat) improves fertility, assisted reproductive technology (ART) success, and sperm quality in men. Therefore, integration of anti-inflammatory dietary patterns as low-risk adjunctive fertility treatments may improve fertility partially or fully and reduce the need for prolonged or intensive pharmacological or surgical interventions.

Inflammatory Markers in Non-Obese Women with Polycystic Ovary Syndrome Are Not Elevated and Show No Correlation with Vitamin D Metabolites

Introduction. Chronic low-grade inflammation is a characteristic of women with polycystic ovary syndrome (PCOS), although this may be obesity-driven rather than an intrinsic facet of PCOS; furthermore, vitamin D deficiency, another common feature of PCOS, is reported to have an association with increased inflammation. Therefore, circulating inflammatory protein levels and circulating levels of vitamin D may be linked in PCOS, though it is unclear which vitamin D metabolites may be important. Methods. We measured plasma levels of 24 inflammatory proteins and 12 matrix metalloproteinases (proteins modulated by the inflammatory process) by slow off-rate modified aptamer (SOMA)-scan plasma protein measurement in weight and aged-matched non-obese non-insulin resistant PCOS (n = 24) and control (n = 24) women. Inflammatory proteins and matrix metalloproteinases were correlated to 25-hydroxy vitamin D₃ (25(OH)D₃), its epimer 25-hydroxy-3epi-vitamin D (3epi25(OH)D) and the active 1,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃) as measured by gold standard isotope-dilution liquid chromatography tandem mass spectrometry. Results. PCOS women had both an elevated free androgen index and circulating anti-mullerian hormone, though insulin resistance was comparable to controls. C-reactive protein, as a standard circulatory marker of inflammation, was comparable between cohorts. Levels of circulating inflammatory proteins and matrix metalloproteinases were not different between the PCOS and control women, with no correlation of 25(OH)D_3, 1,25(OH)₂D₃ or 3epi25(OH)D with any of the inflammatory proteins. Conclusion. In a non-obese PCOS population matched for age and insulin resistance, circulating inflammatory proteins and matrix metalloproteinases were not elevated and did not correlate with 25(OH)D_3, its epimer 3epi25(OH)D or 1,25(OH)₂D₃ in either control or PCOS women, indicating that the inflammatory response is absent and the vitamin D-metabolite independent in non-obese women with PCOS.

Proteomic alteration of endometrial tissues during secretion in polycystic ovary syndrome may affect endometrial receptivity

Embryo implantation is a complex developmental process that requires coordinated interactions among the embryo, endometrium, and the microenvironment of endometrium factors. Even though the impaired endometrial receptivity of patients with polycystic ovary syndrome (PCOS) is known, understanding of endometrial receptivity is limited. A proteomics study in three patients with PCOS and 3 fertile women was performed to understand the impaired endometrial receptivity in patients with PCOS during luteal phases. Through isobaric tags for relative and absolute quantitation (iTRAQ) analyses, we identified 232 unique proteins involved in the metabolism, inflammation, and cell adhesion molecules. Finally, our results suggested that energy metabolism can affect embryo implantation, whereas inflammation and cell adhesion molecules can affect both endometrial conversion and receptivity. Our results showed that endometrial receptive damage in patients with PCOS is not a single factor. It is caused by many proteins, pathways, systems, and abnormalities, which interact with each other and make endometrial receptive research more difficult.

The Kynurenine Pathway and Polycystic Ovary Syndrome: Inflammation as a Common Denominator

Polycystic ovary syndrome (PCOS) is a complex metabolic disorder commonly seen in females of reproductive age. The pathophysiology of PCOS is multifactorial and includes dysfunction in ovarian steroidogenesis and folliculogenesis, impaired gonadotropin levels, insulin resistance, gut microbiota imbalance, genetic predisposition, and lifestyle preferences. Low-grade inflammatory conditions such as obesity and impaired glucose tolerance are common metabolic disturbances in women with PCOS. A growing body of literature suggests strong evidence rendering PCOS in close proximity with chronic inflammation as documented by high levels of serum white blood cells, C-reactive protein, and various proinflammatory cytokines seen in this condition. Inflammation seems to be the most common metabolic denominator between the kynurenine pathway and PCOS. The association of tryptophan and kynurenine pathway has already been well documented in mood disorders, neurodegenerative diseases, chronic pain conditions, and different inflammatory states. In this manuscript, we describe the influence of sex steroid hormones on different enzymes of the KP; inflammatory nature of PCOS and CRP as a marker of IDO/TDO activity; and the effects of altered gut flora in women with PCOS. This review provides a novel view of the available evidence of tryptophan and downstream metabolites in PCOS in the context of underlying inflammation.

The effect of TCF7L2 polymorphisms on inflammatory markers after 16 weeks of legume-based dietary approach to stop hypertension (DASH) diet versus a standard DASH diet: a randomised controlled trial

Backgrounds

This randomized controlled trial aimed to investigate the effects of replacing red meat with legumes in the dietary approach to stop hypertension (DASH) diet on inflammatory markers over 16 weeks in overweight and obese individuals with type 2 diabetes. Also, the modulatory effects of TCF7L2 rs7903146 variant on this effect were assessed.

Methods

In this trial, 300 participants with type 2 diabetes, aged 30–65 years with an identified TCF7L2 rs7903146 genotype, were studied. The participants were randomly assigned to the DASH diet or the legume-based DASH diet over 16 weeks. In the DASH diet group, the participants were instructed to follow the standard DASH diet. The legume-based DASH diet was similar to the standard DASH diet, with the exception that one serving of red meat was replaced with one serving of legumes at least five days a week. At the beginning of the study and 16-week follow-up, venous blood samples were collected from all participants who fasted for 12–14 h overnight. The serum concentration of High-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) was measured using an enzyme-linked immunosorbent assay (ELISA) kit. Also, the serum malondialdehyde (MDA) concentration was assessed based on a colorimetric method using a commercial kit. The primary outcome was the difference in hs-CRP changes between the diets. A secondary outcomes was the difference in IL-6, TNF-α, and MDA between the groups among total population and based on TCF7L2 rs7903146 risk allele (CT + TT) and non-risk allele (CC) separately.

Results

The hs-CRP level reduced in the legume-based DASH diet group as compared to the DASH diet group in the 16-week follow-up group. The levels of TNF-α, IL-6, and MDA reduced after the legume-based DASH diet relative to the DASH diet. Reduction of inflammatory markers was observed in both carriers of rs7903146 risk allele and non-risk allele.

Conclusions

Substituting one serving of red meat with one serving of legumes in DASH diet, at least five days a week, could improve the hs-CRP, TNF-α, IL-6, and MDA in participants with type 2 diabetes regardless of having rs7903146 risk or non-risk allele.

Trial registration IRCT, IRCT20090203001640N17.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12986-022-00671-7.

Shared postulations between bipolar disorder and polycystic ovary syndrome pathologies

INTRODUCTION

Women with bipolar disorder (BD) present a high prevalence of polycystic ovary syndrome (PCOS) and other reproductive disorders even before diagnosis or treatment of the disease. Postulations on the potential molecular mechanisms of comorbid PCOS in women with BD remain limited to influence of medications and need further extension.

OBJECTIVES

This review focuses on evidence suggesting that common metabolic and immune disorders may play an important role in the development of BD and PCOS.

RESULTS

The literature covered in this review suggests that metabolic and immune disorders, including the dysfunction of the hypothalamic-pituitary-adrenal axis, chronic inflammatory state, gut microbial alterations, adipokine alterations and circadian rhythm disturbance, are observed in patients with BD and PCOS. Such disorders may be responsible for the increased prevalence of PCOS in the BD population and indicate a susceptibility gene overlap between the two diseases. Current evidence supports postulations of common metabolic and immune disorders as endophenotype in BD as well as in PCOS.

CONCLUSIONS

Metabolic and immune disorders may be responsible for the comorbid PCOS in the BD population. The identification of hallmark metabolic and immune features common to these two diseases will contribute to the clarification of the effect of BD on the reproductive endocrine function and development of symptomatic treatments targeting the biomarkers of the two diseases.

Saturated fat ingestion stimulates proatherogenic inflammation in polycystic ovary syndrome

Inflammation and dyslipidemia are often present in polycystic ovary syndrome (PCOS). We determined the effect of saturated fat ingestion on circulating heat shock protein-70 (HSP-70) and mononuclear cell (MNC) toll-like receptor-2 (TLR2) gene expression, activator protein-1 (AP-1) activation, and matrix matalloproteinase-2 (MMP-2) protein in women with PCOS. Twenty reproductive-age women with PCOS (10 lean, 10 with obesity) and 20 ovulatory controls (10 lean, 10 with obesity) participated in the study. HSP-70 was measured in serum and TLR2 mRNA and protein, AP-1 activation, and MMP-2 protein were quantified in MNC from blood drawn while fasting and 2, 3, and 5 h after saturated fat ingestion. Insulin sensitivity was derived from an oral glucose tolerance test (IS_OGTT). Androgen secretion was assessed from blood drawn while fasting and 24, 48, and 72 h after human chorionic gonadotropin (HCG) administration. In response to saturated fat ingestion, serum HSP-70, TLR2 gene expression, activated AP-1, and MMP-2 protein were greater in lean women with PCOS compared with lean controls and in women with PCOS and obesity compared with controls with obesity. Both PCOS groups exhibited lower IS_OGTT and greater HCG-stimulated androgen secretion compared with control subjects of their respective weight classes. Lipid-stimulated proatherogenic inflammation marker responses were negatively correlated with IS_OGTT and positively correlated with abdominal adiposity and HCG-stimulated androgen secretion. In PCOS, saturated fat ingestion stimulates proatherogenic inflammation independent of obesity. This effect is greater when PCOS is combined with obesity compared with obesity alone. Abdominal adiposity and hyperandrogenism may perpetuate proatherogenic inflammation.NEW & NOTEWORTHY This paper demonstrates that in polycystic ovary syndrome (PCOS), ingestion of saturated fat triggers a molecular pathway of inflammation known to drive atherogenesis. This effect is independent of obesity as it occurs in lean women with PCOS and not in lean ovulatory control subjects. Furthermore, the combined effects of PCOS and obesity are greater compared with obesity alone.

PCOS and nutritional approaches: Differences between lean and obese phenotype

Polycystic Ovary Syndrome (PCOS) is an endocrine/metabolic disorder with an ever-increasing prevalence. It has various clinical characteristics; the cardinals are androgen excess, oligo-anovulatory infertility, polycystic ovaries, insulin resistance (IR), and cardiometabolic alterations. These disturbances are a consequence of PCOS's complex etiology. PCOS is mainly related to women with obesity; however, there are many PCOS lean patients too. Even though they share some aspects in their metabolic profiles, each group has individual differences in body composition and other parameters. Thus, in order to achieve successful therapeutic strategies, they should be tailored to these details. The authors reviewed PubMed's updated and related publications about body composition and nutritional strategies for PCOS lean and obese patients. As previous reports have determined, dietary patterns are essential in PCOS treatment. Several diets have been studied to control and improve IR, infertility, and cardiometabolic dysfunctions in PCOS. This review will explain the specific features in metabolic characterization and body composition among these patients. Finally, the diverse nutritional strategies used in women with PCOS will be analyzed depending on their lean or obese phenotype.

Association of Prx4, Total Oxidant Status, and Inflammatory Factors with Insulin Resistance in Polycystic Ovary Syndrome

INTRODUCTION

Chronic inflammation and oxidative stress conditions have been reported in women with polycystic ovary syndrome (PCOS). Peroxiredoxin 4 (Prx4) is a related antioxidant in insulin synthesis. We hypothesized that insulin resistance in these women is associated with total oxidant status (TOS) and inflammatory factors.

MATERIALS AND METHODS

Two hundred three people including 104 PCOS patients and 99 healthy women, who were matched for age and body mass index (BMI), entered the study. Waist circumference of the participants was measured; serum glucose, lipid profile, insulin, Prx4, TOS, hs-CRP, and TNF-α were also evaluated.

RESULTS

The Prx4 level was significantly lower in PCOS than in the control group. In addition, marked increase was observed in the concentration of TOS, hs-CRP, and TNF-α in PCOS, compared to the healthy women. There was a positive correlation of TOS with hs-CRP, TNF-α, and HOMA-IR. The risk of PCOS for subjects with high hs-CRP was 60 times greater than those who had low serum hs-CRP concentration; after performing multiple logistic regression analyses with the backward method, TNF-α was considered as an effective biomarker to predict PCOS β = 49.087 (all p < 0.05).

CONCLUSION

This study identified increased oxidative stress and inflammation in PCOS; this may be due to decrease in the antioxidants, such as Prx4.

Lipid-induced mononuclear cell cytokine secretion in the development of metabolic aberration and androgen excess in polycystic ovary syndrome

STUDY QUESTION

What is the effect of saturated fat ingestion on mononuclear cell (MNC) TNFα, IL-6 and IL-1β secretion and circulating IL-6 levels in women with polycystic ovary syndrome (PCOS)?

SUMMARY ANSWER

Women with PCOS exhibit increases in MNC-derived TNFα, IL-6 and IL-1β secretion and circulating IL-6 following saturated fat ingestion even in the absence of obesity, and these increases are linked to metabolic aberration and androgen excess.

WHAT IS KNOWN ALREADY

Cytokine excess and metabolic aberration is often present in PCOS.

STUDY DESIGN, SIZE, DURATION

A cross-sectional design was used in this study of 38 reproductive-age women.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Groups of 19 reproductive-age women with PCOS (10 lean, 9 obese) and 19 ovulatory controls (10 lean, 9 obese) participated in this study that was performed at a tertiary academic medical centre. TNFα, IL-6 and IL-1β secretion was measured from cultured MNC, and IL-6 was measured in plasma from blood sampling while fasting and 2, 3 and 5 h after saturated fat ingestion. Insulin sensitivity was determined using the Matsuda index following an oral glucose tolerance test. Androgen secretion was evaluated with blood sampling while fasting and 24, 48 and 72 h after an HCG injection.

MAIN RESULTS AND THE ROLE OF CHANCE

Lean and obese women with PCOS exhibited lipid-induced incremental AUC increases in MNC-derived TNFα (489-611%), IL-6 (333-398%) and IL-1β (560-695%) secretion and in plasma IL-6 levels (426-474%), in contrast with lean control subjects. In both PCOS groups, insulin sensitivity was lower (42-49%) and androgen secretion after HCG injection was greater (63-110%) compared with control subjects. The MNC-derived TNFα, IL-6 and IL-1β and circulating IL-6 responses were inversely associated with insulin sensitivity and directly associated with fasting lipids and androgen secretion after HCG injection.

LIMITATIONS, REASONS FOR CAUTION

The sample size of each of the four study groups was modest following group assignment of subjects by body mass.

WIDER IMPLICATIONS OF THE FINDINGS

This study showcases the unique pro-inflammatory contribution of circulating MNC in the development of metabolic aberration and androgen excess in PCOS.

STUDY FUNDING/COMPETING INTEREST(S)

This research was supported by grant R01 DK107605 to F.G. from the National Institutes of Health, the Indiana Clinical and Translational Sciences Institute Clinical Research Center which is funded in part by grant UL1TR002529 from the National Institutes of Health, National Center for Advancing Translational Sciences, Clinical and Translational Sciences Award, and the Indiana University Center for Diabetes and Metabolic Diseases funded by grant P30 DK097512 from the National Institutes of Health. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. No conflicts of interest, financial or otherwise, are declared by the authors.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov NCT01489319.

Chronic Low Grade Inflammation in Pathogenesis of PCOS

Polycystic ovary syndrome (PCOS) is a one of the most common endocrine disorders, with a prevalence rate of 5–10% in reproductive aged women. It’s characterized by (1) chronic anovulation, (2) biochemical and/or clinical hyperandrogenism, and (3) polycystic ovarian morphology. PCOS has significant clinical implications and can lead to health problems related to the accumulation of adipose tissue, such as obesity, insulin resistance, metabolic syndrome, and type 2 diabetes. There is also evidence that PCOS patients are at higher risk of cardiovascular diseases, atherosclerosis, and high blood pressure. Several studies have reported the association between polycystic ovary syndrome (PCOS) and low-grade chronic inflammation. According to known data, inflammatory markers or their gene markers are higher in PCOS patients. Correlations have been found between increased levels of C-reactive protein (CRP), interleukin 18 (IL-18), tumor necrosis factor (TNF-α), interleukin 6 (IL-6), white blood cell count (WBC), monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1α (MIP-1α) in the PCOS women compared with age- and BMI-matched controls. Women with PCOS present also elevated levels of AGEs and increased RAGE (receptor for advanced glycation end products) expression. This chronic inflammatory state is aggravating by obesity and hyperinsulinemia. There are studies describing mutual impact of hyperinsulinemia and obesity, hyperandrogenism, and inflammatory state. Endothelial cell dysfunction may be also triggered by inflammatory cytokines. Many factors involved in oxidative stress, inflammation, and thrombosis were proposed as cardiovascular risk markers showing the endothelial cell damage in PCOS. Those markers include asymmetric dimethylarginine (ADMA), C-reactive protein (CRP), homocysteine, plasminogen activator inhibitor-I (PAI-I), PAI-I activity, vascular endothelial growth factor (VEGF) etc. It was also proposed that the uterine hyperinflammatory state in polycystic ovary syndrome may be responsible for significant pregnancy complications ranging from miscarriage to placental insufficiency. In this review, we discuss the most importance evidence concerning the role of the process of chronic inflammation in pathogenesis of PCOS.

The Role of Chronic Inflammation in Polycystic Ovarian Syndrome-A Systematic Review and Meta-Analysis

Although the current literature associates polycystic ovarian syndrome (PCOS) with chronic inflammation, the evidence for this link remains inconclusive and its causal nature remains unclear. The purpose of this systematic review was to assess the inflammatory status in PCOS women and to determine whether it is related to PCOS or to its associated adiposity. We searched electronic databases including PUBMED, EMBASE and MEDLINE, SCOPUS, DynaMed plus, TRIP, ScienceDirect and Cochrane Library, for studies investigating C-reactive protein (CRP) and other inflammatory makers in PCOS women versus healthy controls. Quality and risk of bias for selected studies were assessed using the modified Newcastle-Ottawa scale. CRP data were extracted and pooled using RevMan for calculation of the standardized mean difference (SMD) and 95% confidence interval (CI). Eighty-five eligible studies were included in the systematic review, of which 63 were included in the meta-analysis. Pooled analysis of the 63 studies revealed significantly higher circulating CRP in PCOS women (n = 4086) versus controls (n = 3120) (SMD 1.26, 95%CI, 0.99, 1.53). Sensitivity meta-analysis of 35 high quality studies including non-obese women showed significantly higher circulating CRP in PCOS women versus controls (SMD 1.80, 95%CI, 1.36, 2.25). In conclusion, circulating CRP is moderately elevated in PCOS women independent of obesity, which is indicative of low-grade chronic inflammation.

The role of miRNAs in polycystic ovary syndrome with insulin resistance

PURPOSE

This review aims to summarize the key findings of several miRNAs and their roles in polycystic ovary syndrome with insulin resistance, characterize the disease pathogenesis, and establish a new theoretical basis for diagnosing, treating, and preventing polycystic ovary syndrome.

METHODS

Relevant scientific literature was covered from 1992 to 2020 by searching the PubMed database with search terms: insulin/insulin resistance, polycystic ovary syndrome, microRNAs, and metabolic diseases. References of relevant studies were cross-checked.

RESULTS

The related miRNAs (including differentially expressed miRNAs) and their roles in pathogenesis, and possible therapeutic targets and pathways, are discussed, highlighting controversies and offering thoughts for future directions.

CONCLUSION

We found abundant evidence on the role of differentially expressed miRNAs with its related phenotypes in PCOS. Considering the essential role of insulin resistance in the pathogenesis of PCOS, the alterations of associated miRNAs need more research attention. We speculate that race/ethnicity or PCOS phenotype and differences in methodological differences might lead to inconsistencies in research findings; thus, several miRNA profiles need to be investigated further to qualify for the potential therapeutic targets for PCOS-IR.

Are Heavy Metal Exposure and Trace Element Levels Related to Metabolic and Endocrine Problems in Polycystic Ovary Syndrome?

This study aimed to determine the relationship between the metabolic and endocrinological pathologies in polycystic ovary syndrome (PCOS) and the levels of arsenic, chromium, cadmium, lead, mercury, antimony, zinc, and copper to evaluate the relationship of these toxic metals with inflammatory/oxidative parameters. This study included a total of 154 patients (84 with PCOS, 70 healthy volunteers). Metabolic and endocrine parameters and arsenic, chromium, cadmium, lead, mercury, antimony, zinc, and copper serum levels of the patients were compared between the groups. Considering the action mechanism of toxic metals, serum malondialdehyde (MDA), superoxide dismutase (SOD), serum total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), tumor necrosis factor-alpha (TNFα), and high-sensitivity C-reactive protein (HsCRP) levels were determined. Serum TAS (p = 0.002), OSI (p = 0.006), SOD (p = 0.006), zinc (p = 0.010), and copper (p = 0.030) values were statistically lower whereas TOS (p = 0.008), MDA (p < 0.001), HsCRP (p < 0.001), TNFα (p < 0.001), antimony (p < 0.001), cadmium (p < 0.001), lead (p < 0.001), and mercury (p < 0.001) levels were significantly higher in the PCOS group than those determined in the control group. Antimony was positively correlated with fasting glucose (FG) and HOMA-IR while cadmium, in addition to FG and HOMA-IR, positively correlated with insulin and lead had a positive correlation only with FG (p < 0.05). Also, these three heavy metals correlated positively with some oxidative system and inflammatory parameters and negatively with the antioxidant system parameters (p < 0.05). In conclusion, heavy metal exposures in PCOS may be related to insulin resistance and hirsutism through oxidative and inflammatory mechanisms. This approach can be used to identify the risky patient group and to develop new treatment modalities.

Current concepts of polycystic ovary syndrome pathogenesis

PURPOSE OF REVIEW

This review provides a model for understanding polycystic ovary syndrome (PCOS) pathophysiology and updates the evidence on which it is based. Then, it highlights complimentary molecular genetic and epigenetic advances in understanding PCOS cause.

RECENT FINDINGS

Important studies into PCOS cause built on the 2014 discovery of a novel regulatory protein variant that underlies the typical PCOS steroidogenic abnormalities: DENND1A.V2 (differentially expressed in normal and neoplastic development, isoform 1A, variant 2). Over 30 DENND1A gene variants have been found, the vast majority upstream of the coding sequence and potentially regulatory. These variants are individually uncommon but collectively plausibly cause 50% of PCOS. Anti-Müllerian hormone (AMH)/AMH receptor variants with decreased function possibly cause 6.7% of PCOS. DENNND1A was recently reported to belong to a signaling network that upregulates luteinizing hormone receptor expression and insulin mitogenic signaling. Prenatal androgen administration has proven to be a potent epigenetic regulator that causes transgenerational epigenomic changes in a mouse PCOS model with similarities to those in human PCOS and PCOS daughters.

SUMMARY

In addition to finding how gene variants contribute to PCOS pathogenesis, better understanding of androgen epigenetic mechanisms of action in diverse tissues can be expected to expand our understanding of PCOS pathogenesis.

Salicylate administration suppresses the inflammatory response to nutrients and improves ovarian function in polycystic ovary syndrome

Oxidative stress (OS) and inflammation are often present in polycystic ovary syndrome (PCOS). We examined the effects of salsalate treatment on nutrient-induced OS and inflammation, ovarian androgen secretion, ovulation, and insulin sensitivity in PCOS. Eight lean insulin-sensitive women with PCOS and eight age- and body composition-matched ovulatory controls for baseline comparison participated in the study. The women with PCOS underwent a 12-wk treatment of salsalate, a nonsteroidal anti-inflammatory drug, at a dose of 3 g daily. Markers of OS and inflammation were quantified in mononuclear cells (MNC) and plasma from blood drawn fasting and 2 h after saturated fat ingestion before and after treatment. Ovarian androgen secretion was assessed from blood drawn fasting and 24, 48, and 72 h after human chorionic gonadotropin (HCG) administration before and after treatment. Ovulation was documented based on biphasic basal body temperatures and luteal range progesterone elevations. A two-step pancreatic clamp was performed pre- and posttreatment to measure basal endogenous glucose production (EGP) and the steady-state glucose disposal rate (GDR) during the euglycemic phase and markers of OS and inflammation in MNC and plasma during the hyperglycemic phase. Salsalate administration suppressed lipid- and glucose-stimulated reactive oxygen species generation, activated nuclear factor-κB and circulating tumor necrosis factor-α, normalized basal androgen levels, and lowered HCG-stimulated androgen secretion without altering EGP or GDR. Four salsalate-treated subjects responded with two consecutive ovulations. We conclude that in PCOS, salsalate-induced suppression of OS and inflammation ameliorates ovarian androgen hypersecretion and may induce ovulation while maintaining insulin action.