Mechanisms of Adiponectin Action in Fertility: An Overview from Gametogenesis to Gestation in Humans and Animal Models in Normal and Pathological Conditions

Metabolic and hormonal profiles and productive performance in primiparous and multiparous cows grazing different forage allowance in late gestation

The aim of this study was to evaluate two levels of forage allowance (FA) during the prepartum period on metabolic, hormonal, productive, and reproductive variables in primiparous (P) and multiparous (M) beef cows. Six weeks before calving, 40 P and 42 M cows were assigned to two FA (native pastures) treatments until calving (day 0): High (15 kg DM/100 BW; H) and Low (5 kg DM/100 BW; L). After calving all cows were managed together. High FA cows presented greater intake than L cows, while M tended to have greater intake than P cows. Increased herbage allowance in late gestation in beef cows successfully improved forage intake and energy balance reflected in body condition score and metabolic and endocrine markers. Also, high forage allowance increased milk yield (5.4 vs 4.6 kg/d, P < 0.05) and calves daily gain rate during the first two months of age (0.88 vs 0.82 kg/d, P < 0.05) in H respect to L cows. Pregnancy rate was greater in H vs L cows (40 vs 28 %, P < 0,05). The endocrine metabolic response to higher forage allowance depended on parity, as primiparous cows showed a greater imbalance around calving. Moreover, most primiparous cows were not pregnant at the end of the breeding season, consistent with their prolonged anestrous. Multiparous cows had better productive and reproductive performance than primiparous cows, showing that growing cows have a pronounced negative energy balance reflected in most of the evaluated parameters.

Adiponectin receptor 1 regulates endometrial receptivity via the adenosine monophosphate‑activated protein kinase/E‑cadherin pathway

Endometrial receptivity is essential for successful embryo implantation and pregnancy initiation and is regulated via various signaling pathways. Adiponectin, an important adipokine, may be a potential regulator of reproductive system functions. The aim of the present study was to elucidate the regulatory role of adiponectin receptor 1 (ADIPOR1) in endometrial receptivity. The endometrial receptivity between RL95‑2 and AN3CA cell lines was confirmed using an in vitro JAr spheroid attachment model. 293T cells were transfected with control or short hairpin (sh)ADIPOR1 vectors and RL95‑2 cells were transduced with lentiviral particles targeting ADIPOR1. Reverse transcription‑quantitative PCR and immunoblot assays were also performed. ADIPOR1 was consistently upregulated in the endometrium during the mid‑secretory phase compared with that in the proliferative phase and in receptive RL95‑2 cells compared with that in non‑receptive AN3CA cells. Stable cell lines with diminished ADIPOR1 expression caused by shRNA showed reduced E‑cadherin expression and attenuated in vitro endometrial receptivity. ADIPOR1 regulated AMP‑activated protein kinase (AMPK) activity in endometrial epithelial cells. Regulation of AMPK activity via dorsomorphin and 5‑aminoimidazole‑4‑carboxamide ribonucleotide affected E‑cadherin expression and in vitro endometrial receptivity. The ADIPOR1/AMPK/E‑cadherin axis is vital to endometrial receptivity. These findings can help improve fertility treatments and outcomes.

Cigarette smoke extract decreases human bone marrow mesenchymal stromal cell adipogenic differentiation

BACKGROUND

Smoking and nicotine impose detrimental health effects including adipose tissue dysfunction. Despite extensive physiological evidence, the cellular mechanisms remain poorly understood, with few studies examining the effects of cigarette smoke extract (CSE) or nicotine on adipocyte differentiation.

METHODS

Primary human bone marrow-derived mesenchymal stromal cells (MSCs) were exposed to CSE or nicotine (50-500 ng/ml) during adipogenic differentiation. Cell viability and metabolic activity were assessed via MTT assay. Lipid droplet accumulation was evaluated using Sudan III staining and quantitative image analysis. Adiponectin, IL6, and IL8 concentrations were measured after 35 days using ELISA.

RESULTS

At these doses, CSE and nicotine do not immediately affect cell viability but inhibit undifferentiated cell proliferation. Notably, both agents at 50 ng/ml significantly increased lipid accumulation during adipogenesis, while higher CSE doses nearly completely inhibited this process. Additionally, CSE dose-dependently decreased adiponectin secretion and increased IL6 and IL8, indicating a shift towards an inflammatory state. Nicotine alone primarily increased IL6 secretion with less pronounced effects.

CONCLUSION

The study highlights the complex impact of CSE and nicotine on adipocyte function during early differentiation from MSCs. Dose-dependent changes in lipid accumulation, cytokine, and adiponectin secretion induced by CSE and nicotine can partly explain smoking-related adipose tissue dysfunction.

Enhanced activation of signaling pathway by recombinant human adiponectin from genome-edited chickens

Adiponectin (ADPN) exerts various cellular and metabolic functions by activating signaling pathways, including extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) pathways, the protein kinase B (Akt) pathway, and the p38 mitogen-activated protein kinase (MAPK) pathway. However, generating functional recombinant human adiponectin (hADPN) in bacterial or mammalian cells is challenging. Although ADPN agonist peptides have been developed, problems like stability, solubility, and affinity for receptors remain. Recently, a genome-edited chicken bioreactor system was established, ensuring efficient ADPN production with optimal post-transcriptional modifications. We assessed the ability of egg white (EW)-derived hADPN, commercial hADPN, various ADPN agonist peptides, and globular ADPN on activation of the ERK1/2, Akt, and p38 MAPK pathways. EW-derived hADPN, abundant in hexamers and high molecular weight multimers, significantly phosphorylated ERK1/2 in serum-starved HEK293 cells after 15min of treatment. Comparative analysis revealed that EW-derived hADPN and commercial hADPN induced greater phosphorylation of ERK1/2, Akt, and p38 MAPK than ADPN agonist peptides and globular ADPN, with EW-derived hADPN showing the highest activation. In summary, the finding that EW-derived hADPN strongly activates the ERK1/2, Akt, p38 MAPK signaling pathways highlights that an ADPN production system based on genome-edited chickens is an advantageous alternative to existing methods.

Determination of Fertility Hormones and Adipokines by LC-MRM/MS Analysis

Due to the increase in the rate of male and female infertility, assisted fertilization practices are currently adopted as valid support for couples unable to get pregnant. Analytical approaches for fertility hormone dosages are constantly being developed, following the technological progress of fertilization methods that have evolved for more than a century. Indeed, the analysis of fertility hormones in serum samples is a common clinical practice to check the fertility state, but absolute quantification of these hormones is a great challenge due to biological variability and low serum concentrations. Currently, ELISA (enzyme-linked immunosorbent assay) based methods are the most used analytical techniques to quantify hormones in blood in clinical settings. The current Article discusses the development of a liquid chromatography-tandem mass spectrometry method (LC-MS/MS) to monitor multiple fertility hormones of a protein nature in a single chromatographic run, i.e., LH (luteinizing hormone), FSH (follicle-stimulating hormone), TSH (thyroid-stimulating hormone), AMH (anti-Müllerian hormone), adiponectin, ghrelin, leptin, glucagon, and obestatin. Particular attention has been paid to the AMH hormone, whose ELISA-based quantification is known to be controversial due to the poor reproducibility between the various kits used. For AMH, the internal standard method was used for the quantitative determination to compare mass spectrometry data to the ELISA assays performed by an accredited analysis laboratory on a cohort of samples from women aged between 18 and 60 years. The ability to monitor multiple transitions by LC-MRM/MS ensured both high specificity and high selectivity, which is necessary for the quantification of protein and steroid hormones, besides improvements in data reproducibility and reduced analysis times and costs.

Key Players in the Complex Pathophysiology of Obesity: A Cross-Talk Between the Obesogenic Genes and Unraveling the Metabolic Pathway of Action of Capsaicin and Orange Peel

Obesity is a widespread prevailing health concern with multifactorial causes. Among the various defined molecular targets associated with obesity, peroxisome proliferator activated receptor gamma, leptin, ghrelin, and adiponectin play crucial roles in fundamental processes including energy balance, adipose tissue biology, and metabolic health, making them particularly significant in the study of obesity.Capsaicin and orange peel exhibit promising anti-obesity properties through their thermogenic, metabolic, and anti-inflammatory effects. Potential pathways for therapeutic approaches in the management of obesity are provided by these targets. The lipid-lowering and anti-obesity benefits of specific plant species have been highlighted in Asian medicine. Due to the potential anti-obesity qualities, capsaicin, which is derived from chilli peppers, and orange peel extract has been focused in this review. Capsaicin causes apoptosis in preadipocytes and adipocytes and suppresses adipogenesis. Citrus fruits are a significant source of bioactive substances, primarily flavonoids. Due to their ability to reduce adipocyte development and cellular lipid content, citrus polyphenols are helpful in the control of obesity. This extensive analysis offers insights into new treatment approaches for the prevention and management of obesity and metabolic syndrome by examining the interactions of molecular variables in obesity as well as the possible anti-obesity advantages of capsaicin and orange peel extract.

Depleting inositol pyrophosphate 5-InsP7 protected the heart against ischaemia-reperfusion injury by elevating plasma adiponectin

AIMS

Adiponectin is an adipocyte-derived circulating protein that exerts cardiovascular and metabolic protection. Due to the futile degradation of endogenous adiponectin and the challenges of exogenous administration, regulatory mechanisms of adiponectin biosynthesis are of significant pharmacological interest.

METHODS AND RESULTS

Here, we report that 5-diphosphoinositol 1,2,3,4,6-pentakisphosphate (5-InsP7) generated by inositol hexakisphosphate kinase 1 (IP6K1) governed circulating adiponectin levels via thiol-mediated protein quality control in the secretory pathway. IP6K1 bound to adiponectin and DsbA-L and generated 5-InsP7 to stabilize adiponectin/ERp44 and DsbA-L/Ero1-Lα interactions, driving adiponectin intracellular degradation. Depleting 5-InsP7 by either IP6K1 deletion or pharmacological inhibition blocked intracellular adiponectin degradation. Whole-body and adipocyte-specific deletion of IP6K1 boosted plasma adiponectin levels, especially its high molecular weight forms, and activated AMPK-mediated protection against myocardial ischaemia-reperfusion injury. Pharmacological inhibition of 5-InsP7 biosynthesis in wild-type but not adiponectin knockout mice attenuated myocardial ischaemia-reperfusion injury.

CONCLUSION

Our findings revealed that 5-InsP7 is a physiological regulator of adiponectin biosynthesis that is amenable to pharmacological intervention for cardioprotection.

Emerging Perspectives on the Impact of Diabetes Mellitus and Anti-Diabetic Drugs on Premenstrual Syndrome. A Narrative Review

Diabetes mellitus (DM) and premenstrual syndrome (PMS) are global health challenges. Both disorders are often linked to a range of physical and psychological symptoms that significantly impact the quality of life of many women. Yet, the exact relation between DM and PMS is not clear, and the management of both conditions poses a considerable challenge. In this review, we aimed to investigate the interplay between DM, anti-diabetic drugs, and the different theories and symptoms of PMS. Female sex hormones are implicated in the pathophysiology of PMS and can also impair blood glucose control. In addition, patients with diabetes face a higher susceptibility to anxiety and depression disorders, with a significant number of patients experiencing symptoms such as fatigue and difficulty concentrating, which are reported in patients with PMS as well. Complications related to diabetic medications, such as hypoglycemia (with sulfonylurea) and fluid retention (with thiazolidinediones) may also mediate PMS-like symptoms. DM can, in addition, disturb the normal gut microbiota (GM), with a consequent loss of beneficial GM metabolites that guard against PMS, particularly the short-chain fatty acids and serotonin. Among the several available anti-diabetic drugs, those (1) with an anti-inflammatory potential, (2) that can preserve the beneficial GM, and (3) possessing a lower risk for hypoglycemia, might have a favorable outcome in PMS women. Yet, well-designed clinical trials are needed to investigate the anti-diabetic drug(s) of choice for patients with diabetes and PMS.

The mysterious association between adiponectin and endometriosis

Adiponectin is a pleiotropic cytokine predominantly derived from adipose tissue. In addition to its role in regulating energy metabolism, adiponectin may also be related to estrogen-dependent diseases, and many studies have confirmed its involvement in mediating diverse biological processes, including apoptosis, autophagy, inflammation, angiogenesis, and fibrosis, all of which are related to the pathogenesis of endometriosis. Although many researchers have reported low levels of adiponectin in patients with endometriosis and suggested that it may serve as a protective factor against the development of the disease. Therefore, the purpose of this review was to provide an up-to-date summary of the roles of adiponectin and its downstream cytokines and signaling pathways in the aforementioned biological processes. Further systematic studies on the molecular and cellular mechanisms of action of adiponectin may provide novel insights into the pathophysiology of endometriosis as well as potential therapeutic targets.

Impact of endometriosis on the ovarian follicles

A significant body of evidence has supported a negative impact of endometriosis on ovarian follicles; however, the origin and relevance of this ovarian impairment in endometriosis is still a matter of debate. The ovarian damage can be caused by endometriosis itself or by surgeries aiming to remove endometriotic lesions. In this review, we summarized the existing knowledge on the mechanisms by which endometriosis can impact the ovarian follicles, from molecular to clinical points of view. From a molecular standpoint, the presence of endometriosis or its consequences can induce oxidative stress, inflammation, aberrant mitochondrial energy metabolism and inappropriate steroid production in granulosa cells, phenomena that may impair the quality of oocytes to variable degrees. These alterations may have clinical relevance on the accelerated exhaustion of the ovarian reserve, on the ovarian response to gonadotrophin stimulation in IVF cycles and on the competence of the oocytes. Critical points to be considered in current clinical practices related to fertility issues in endometriosis are discussed.

Bariatric Surgery in Women with Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is the most common endocrine condition in premenopausal women and is a common cause of anovulatory subfertility. Although obesity does not form part of the diagnostic criteria, it affects a significant proportion of women with PCOS and is strongly implicated in the pathophysiology of the disease. Both PCOS and obesity are known to impact fertility in women; obesity also reduces the success of assisted reproductive technology (ART). With or without pharmacotherapy, lifestyle intervention remains the first-line treatment in women with PCOS and obesity. Bariatric surgery is still an experimental treatment in women with PCOS and subfertility. This review will present an overview of the pathophysiology of PCOS and obesity and the role of bariatric surgery. Although data are sparse regarding the impact of bariatric surgery on subfertility in women with PCOS and obesity, existing studies point to a beneficial role in treating metabolic and reproductive dysfunction.

Autophagic and apoptotic proteins in goat corpus luteum and the effect of Adiponectin/AdipoRon on luteal cell autophagy and apoptosis

The most abundant adipokine Adiponectin (APN) is present in ovaries. AdipoRon is a small molecule oral APN receptor agonist that binds and activates APN receptors. However, the function of APN/AdipoRon in regulation of luteal cell processes has not been elucidated. To investigate autophagic and apoptotic proteins in goat CLs and effects of APN/AdipoRon on goat luteal autophagy and apoptosis, goat CLs were collected during the early, mid and late luteal stages of the estrous cycle to evaluate autophagic and apoptotic protein patterns. LC3B, Beclin 1, Caspase-3 and Bax/Bcl-2 as well as p-AMPK were differentially abundant at different stages of CL development. All these proteins were primarily localized in large and small luteal steroidogenic cells. Then, isolated luteal steroidogenic cells were evaluated to ascertain the functions and mechanism of APN/AdipoRon in luteal autophagy and apoptosis. Treatment with AdipoRon (25 and 50 μM) and APN (1 μg/mL) for 48 h resulted in a decrease in cell viability and P4 level, increased autophagic and apoptotic proteins. Treatment with AdipoRon (25 μM) led to rapid and transient p-AMPK activation, with p-AMPK elevated at 30 min to 1 h with there being a return to a basal concentration at 2 h post-treatment. Moreover, treatment with AdipoRon led to an increase in autophagy by activating AMPK, which was markedly reduced with treatment with an AMPK inhibitor Compound C and siAMPK, however, abundances of apoptotic proteins were not affected by these treatments. In conclusion, autophagy and apoptosis are involved in the structural regression of goat CL. APN/AdipoRon led to a lesser cell viability and P4 concentration, and activated autophagy through induction of the AMPK while there was induction of apoptosis through an AMPK - independent pathway in goat luteal cells.

The multiple actions of grape and its polyphenols on female reproductive processes with an emphasis on cell signalling

Grapes are an economically important fruit crop, and their polyphenols (mainly phenolic acids, flavanols, flavonols, anthocyanins, proanthocyanidins, and stilbenes) can exert a wide range of health benefits as an interesting and valuable dietary supplement for natural complementary therapy. However, their potential physiological and therapeutic actions on reproductive processes have not been sufficiently elucidated. This evidence-based study presents current knowledge of grape extracts and polyphenols, as well as their properties and therapeutical actions in relation to female reproduction in a nutshell. Grape extract, and its polyphenols such as resveratrol, proanthocyanidin B2 or delphinidin may influence female reproductive physiology and pathology, as well as regulate multiple signaling pathways related to reproductive hormones, steroid hormones receptors, intracellular regulators of oxidative stress and subsequent inflammation, apoptosis, and proliferation. Their role in the management of ovarian cancer, age-related reproductive insufficiency, ovarian ischemia, PCOS, or menopausal syndrome has been indicated. In particular, the potential involvement of grapeseed extracts and/or proanthocyanidin B2 and delphinidin on ovarian steroidogenesis, oocyte maturation, and developmental capacity has been implicated, albeit at different regulatory levels. Grape polyphenols exert a wide range of health benefits posing grape extract as an interesting and valuable dietary supplement for natural complementary therapy. This evidence-based study focuses on the actions of grapeseed extract and grape polyphenols on female reproductive processes at various regulatory levels and multiple signalling pathways by regulating reproductive hormones (GnRH, gonadotropins, prolactin, steroid hormones, IGFBP), steroid receptors, markers of proliferation and apoptosis. However, lack of knowledge of standardized dosages so far limits their clinical application despite the wide range of their biological and therapeutic potentials.

Adiponectin: A Promising Target for the Treatment of Diabetes and Its Complications

Diabetes mellitus, a chronic metabolic disorder characterized by hyperglycemia, presents a formidable global health challenge with its associated complications. Adiponectin, an adipocyte-derived hormone, has emerged as a significant player in glucose metabolism and insulin sensitivity. Beyond its metabolic effects, adiponectin exerts anti-inflammatory, anti-oxidative, and vasoprotective properties, making it an appealing therapeutic target for mitigating diabetic complications. The molecular mechanisms by which adiponectin impacts critical pathways implicated in diabetic nephropathy, retinopathy, neuropathy, and cardiovascular problems are thoroughly examined in this study. In addition, we explore possible treatment options for increasing adiponectin levels or improving its downstream signaling. The multifaceted protective roles of adiponectin in diabetic complications suggest its potential as a novel therapeutic avenue. However, further translational studies and clinical trials are warranted to fully harness the therapeutic potential of adiponectin in the management of diabetic complications. This review highlights adiponectin as a promising target for the treatment of diverse diabetic complications and encourages continued research in this pivotal area of diabetes therapeutics.

Spexin role in human granulosa cells physiology and PCOS: expression and negative impact on steroidogenesis and proliferation†

Spexin (SPX) is a novel neuropeptide and adipokine negatively correlated with obesity and insulin resistance. A recent study investigated expression and regulatory function of SPX in the hypothalamus and pituitary; however, the effect on ovarian function is still unknown. The aim of this study was to characterize the expression of SPX and its receptors, galanin receptors 2 and 3 (GALR2/3), in the human ovary and to study its in vitro effect on granulosa cells (GC) function. Follicular fluid (FF) and GC were obtained from normal weight and obese healthy and diagnosed with polycystic ovarian syndrome (PCOS) women. Expression of SPX and GALR2/3 in the ovary was studied by qPCR, western blot, and immunohistochemistry. The level of SPX in FF was assessed by enzyme-linked immunosorbent assay. The in vitro effect of recombinant human SPX on GC proliferation, steroidogenesis, and signaling pathways (MAP3/1, STAT3, AKT, PKA) was analyzed. Moreover, GC proliferation and estradiol (E2) secretion were measured with and without an siRNA against GALR2/3 and pharmacological inhibition of the above kinases. The results showed that both the SPX concentration in FF and its gene expression were decreased in GC of obese and PCOS women, while the protein expression of GALR2/3 was increased. We noted that SPX reduced GC proliferation and steroidogenesis; these effects were mediated by GALR2/3 and kinases MAP3/1, AKT, and STAT3 for proliferation or kinases MAP3/1 and PKA for E2 secretion. The obtained data clearly documented that SPX is a novel regulator of human ovarian physiology and possibly plays a role in PCOS pathogenesis.

Linking Adiponectin and Its Receptors to Age-Related Macular Degeneration (AMD)

In recent years, there has been a captivating focus of interest in elucidating the intricate crosstalk between adiponectin (APN), a versatile fat-associated adipokine and ocular pathologies. Unveiling the intricate relationship between adipocytokine APN and its receptors (AdipoRs) with aging eye disorders has emerged as a fascinating frontier in medical research. This review article delves into this connection, illuminating the hidden influence of APN on retinal health. This comprehensive review critically examines the latest findings and breakthroughs that underscore the pivotal roles of APN/AdipoRs signaling in maintaining ocular homeostasis and protecting against eye ailments. Here, we meticulously explore the intriguing mechanisms by which APN protein influences retinal function and overall visual acuity. Drawing from an extensive array of cutting-edge studies, the article highlights APN's multifaceted functions, ranging from anti-inflammatory properties and oxidative stress reduction to angiogenic regulation within retinal and macula tissues. The involvement of APN/AdipoRs in mediating these effects opens up novel avenues for potential therapeutic interventions targeting prevalent aging eye conditions. Moreover, this review unravels the interplay between APN signaling pathways and age-related macular degeneration (AMD). The single-cell RNA-seq results validate the expression of both the receptor isoforms (AdipoR1/R2) in retinal cells. The transcriptomic analysis showed lower expression of AdipoR1/2 in dry AMD pathogenesis compared to healthy subjects. The inhibitory adiponectin peptide (APN1) demonstrated over 75% suppression of CNV, whereas the control peptide did not exert any inhibitory effect on choroidal neovascularization (CNV). The elucidation of these relationships fosters a deeper understanding of adipose tissue's profound influence on ocular health, presenting new prospects for personalized treatments and preventative measures. Because APN1 inhibits CNV and leakage, it can be used to treat human AMD, although the possibility to treat human AMD is in the early stage and more clinical research is needed. In conclusion, this review provides a captivating journey into the enthralling world of APN, intertwining the realms of adipose biology and ophthalmology in aging.

Potential factors result in diminished ovarian reserve: a comprehensive review

The ovarian reserve is defined as the quantity of oocytes stored in the ovary or the number of oocytes that can be recruited. Ovarian reserve can be affected by many factors, including hormones, metabolites, initial ovarian reserve, environmental problems, diseases, and medications, among others. With the trend of postponing of pregnancy in modern society, diminished ovarian reserve (DOR) has become one of the most common challenges in current clinical reproductive medicine. Attributed to its unclear mechanism and complex clinical features, it is difficult for physicians to administer targeted treatment. This review focuses on the factors associated with ovarian reserve and discusses the potential influences and pathogenic factors that may explain the possible mechanisms of DOR, which can be improved or built upon by subsequent researchers to verify, replicate, and establish further study findings, as well as for scientists to find new treatments.

Role of leptin, adiponectin, and kisspeptin in polycystic ovarian syndrome pathogenesis

INTRODUCTION

Polycystic ovarian syndrome (PCOS) affects 5-20% of females and is the most common cause of anovulatory infertility. Leptin seems to have an important role in reproduction. Many reproductive pathologies such as preeclampsia, PCOS, and endometriosis are associated to plasma adiponectin levels. Kisspeptin levels are increased in PCOS women.

EVIDENCE ACQUISITION

A review of the literature was completed through the PubMed database aiming to find articles regarding leptin, adiponectin and kisspeptin and if they are related to PCOS pathogenesis.

EVIDENCE SYNTHESIS

Even today it is not clear what is the role of leptin in women with PCOS, although most of the researchers found increased levels of leptin as well as leptin resistance in PCOS (both obese and lean individuals). Many more longitudinal studies should be done to discover the usefulness of measuring adiponectin in prepubertal women who apparently have a possibility to develop PCOS to find out if they finally develop PCOS. Most of the researchers found that PCOS women have decreased levels of adiponectin unrelated to BMI levels. Nevertheless, not all studies had the same result. Moreover, it is necessary more studies to be made to investigate the connection between kisspeptin and other metabolic factors such as LH and insulin resistance.

CONCLUSIONS

In general, it remains inconclusive whether leptin, adiponectin, and kisspeptin can be used as clinical and/or biochemical markers of PCOS. Therefore, it is essential to review the current data with regards to the association between PCOS and circulating leptin, adiponectin, and kisspeptin in women with PCOS.

Adipokines expression in reproductive tract, egg white and embryonic annexes in hen

In mammals, molecules mainly secreted by white adipose tissue named adipokines are also synthetized locally in the reproductive tract and are able to influence reproductive functions. In avian species, previous studies indicated that the adipokine chemerin is highly abundant in the albumen, compared to the yolk and this was associated to high chemerin expression in the magnum. In addition, the authors observed that chemerin and its receptors are expressed by allantoic and amniotic membranes and chemerin is present in fluids during the embryo development. Here, we studied other adipokines, including adiponectin, visfatin, apelin, and adipolin in egg white and their known receptors in the active (egg-laying hen) and regressed (hen not laying) oviduct and embryonic annexes during embryo development. By using Western blot, RT-qPCR analysis and immunohistochemistry, we demonstrated the expression of different adipokines in the egg albumen (visfatin) and the reproductive tract (adiponectin, visfatin, apelin, adipolin, and their cognate receptors) according the position of egg in the oviduct. We showed that the expression of adipokines and adipokines receptors was strongly reduced in the regressed oviducts (arrested laying hen). Results indicated that visfatin and adiponectin appeared at ED11 to 14 and increased until ED18 in amniotic fluid whereas it was found from ED7 and was unchanged during embryo development in allantoic fluid. Taken together, adipokines and their receptors are expressed in the egg white, the reproductive tract and the embryonic annexes. Data obtained suggest important functions of theses metabolic hormones during the chicken embryo development. Thus, adipokines could be potential biomarkers to improve the embryo development.

Apelin is found in human sperm and testis and is raised in inflammatory pathological conditions

Apelin/APJ receptor (R) is involved in many oxidative stress-induced pathological conditions. Since this system is not yet explored in male reproduction, we studied apelin/APJ-R in human semen and testis. Semen of 41 infertile patients with varicocele, genitourinary infections, unexplained infertility and 12 fertile men was analysed (WHO guidelines, 2021). Apelin was quantified by ELISA in seminal fluid and spermatozoa, interleukin (IL)-1β in seminal fluid. Apelin/APJ-R were immunolocalized in spermatozoa and testis. Apelin was present in spermatozoa and its levels were negatively correlated with normal sperm morphology% (r = -0.857; p < 0.001), and positively with IL-1β levels (r = 0.455; p < 0.001). Apelin and IL-1β concentrations were increased in patients' samples with varicocele (apelin p < 0.01; IL-1β p < 0.05) and infections (apelin p < 0.01; IL-1β p < 0.001). By logistic regression analysis, apelin (OR 1.310; p = 0.011) and IL-1β (OR 1.572; p = 0.005) were predictors of inflammatory diseases (varicocele, infections). Apelin and APJ-R immunofluorescence labels were weak in sperm tail of fertile men and intense along tail, cytoplasmic residues and post-acrosomal sheath of sperm from infertile men. In testis, apelin and APJ-R labels were evident in Leydig cells and weak inside the seminiferous tubule. Apelin/APJ-R system is present in human spermatozoa and testicular tissue and probably involved in human fertility.

Role of Leptin and Adiponectin in Carcinogenesis

Hormones produced by adipocytes, leptin and adiponectin, are associated with the process of carcinogenesis. Both of these adipokines have well-proven oncologic potential and can affect many aspects of tumorigenesis, from initiation and primary tumor growth to metastatic progression. Involvement in the formation of cancer includes interactions with the tumor microenvironment and its components, such as tumor-associated macrophages, cancer-associated fibroblasts, extracellular matrix and matrix metalloproteinases. Furthermore, these adipokines participate in the epithelial-mesenchymal transition and connect to angiogenesis, which is critical for cancer invasiveness and cancer cell migration. In addition, an enormous amount of evidence has demonstrated that altered concentrations of these adipocyte-derived hormones and the expression of their receptors in tumors are associated with poor prognosis in various types of cancer. Therefore, leptin and adiponectin dysfunction play a prominent role in cancer and impact tumor invasion and metastasis in different ways. This review clearly and comprehensively summarizes the recent findings and presents the role of leptin and adiponectin in cancer initiation, promotion and progression, focusing on associations with the tumor microenvironment and its components as well as roles in the epithelial-mesenchymal transition and angiogenesis.

Relationship between chronic obstructive pulmonary disease and adiponectin concentrations: An updated meta-analysis and single-cell RNA sequencing

BACKGROUND

Adipose tissue, being an organ of the endocrine system, can influence the severity of chronic obstructive pulmonary disease (COPD). Even though several inflammatory markers can potentially significantly influence lung function, the precise function of adipokines, like adiponectin, in COPD is still disputed. To analyze the association of COPD with adiponectin concentrations, a meta-analysis of the most recent literature and single-cell sequencing data were conducted.

METHODS

Studies in Embase, PubMed, Cochrane Library, and Web of Science were browsed to obtain relevant data, which were then assessed with the aid of R 4.1.3 and STATA 11.0 software. Standardized mean differences and correlation coefficients aided the analysis of effect values. Moreover, a single-cell sequencing GSE136831 dataset was retrieved to ascertain the mRNA expression of adiponectin gene (ADIPOQ) in the lung tissue of COPD patients to confirm the difference in the expression of adiponectin between the case and control groups.

RESULTS

This meta-analysis comprised 18 publications involving 24 studies. The overall combined data established the concentration of plasma/serum adiponectin as significantly higher in patients with COPD compared to healthy subjects. Subgroup analyses based on disease status, specimen type, ethnicity, study design method, measurement method, and age of COPD patients demonstrated that all patients with COPD had elevated levels of adiponectin compared to healthy controls. When subgroup analysis was performed for gender alone, the results depicted that male COPD patients had significantly higher adiponectin than healthy males, while female patients of COPD had elevated adiponectin compared to healthy females. Furthermore, it was found that plasma/serum adiponectin appeared to be positively correlated with tumor necrosis factor-α, and it was negatively correlated with FEV1% and FEV1/FVC. The results of single-cell sequencing data suggested that ADIPOQ mRNA was mainly expressed in alveolar epithelial cells, and the level of ADIPOQ mRNA was higher in lung tissues of patients with COPD than in lung tissues of healthy subjects.

CONCLUSION

This meta-analysis suggests that the levels of plasma/serum adiponectin are significantly elevated in patients with COPD versus controls. Tumor necrosis factor-α, FEV1/FVC, and FEV1% may all be associated with the concentrations of adiponectin.

Emerging Role of Adiponectin/AdipoRs Signaling in Choroidal Neovascularization, Age-Related Macular Degeneration, and Diabetic Retinopathy

Age-related macular degeneration (AMD), a leading cause of irreversible blindness in adults, may result in poor central vision, making it difficult to see, read, and drive. AMD is generally classified in either dry or wet types. Milder cases of dry AMD may progress to geographic atrophy (GA), leading to significant visual disability; wet, or neovascular AMD, which involves choroidal neovascularization (CNV), can lead to complete loss of central vision. Adiponectin (APN) discovery in the mid-1990's and, subsequently, its two cognate receptors (AdipoRs) in the early 2000s have led to a remarkable progress in better understanding metabolic disorders, as well as metabolism-associated ocular pathology. APN/AdipoRs signaling plays a central role in a variety of molecular and cellular physiological events, including glucose and lipid metabolism, whole-body energy regulation, immune and inflammation responses, insulin sensitivity and retinal cell biological functions. This review is an amalgamation of recent information related to APN/AdipoRs in the pathophysiology of retinal diseases and furthers its association with AMD and diabetic retinopathy. Additionally, we present our original research, where we designed control peptide and CNV inhibitory peptide from the globular region of APN to see the effect of these peptides on the mouse model of laser-induced CNV. The inhibitory peptide (APN1) inhibited CNV by more than 75% while the control peptide did not inhibit CNV.

Endoplasmic reticulum in oocytes: spatiotemporal distribution and function

ENDOPLASMIC RETICULUM IN OOCYTES

The storage and release of calcium ions (Ca2 +) in oocyte maturation and fertilization are particularly noteworthy features of the endoplasmic reticulum (ER). The ER is the largest organelle in the cell composed of rough ER, smooth ER, and nuclear envelope, and is the main site of protein synthesis, transport and folding, and lipid and steroid synthesis. An appropriate calcium signaling response can initiate oocyte development and embryogenesis, and the ER is the central link that initiates calcium signaling. The transition from immature oocytes to zygotes also requires many coordinated organelle reorganizations and changes. Therefore, the purpose of this review is to generalize information on the function, structure, interaction with other organelles, and spatiotemporal localization of the ER in mammalian oocytes. Mechanisms related to maintaining ER homeostasis have been extensively studied in recent years. Resolving ER stress through the unfolded protein response (UPR) is one of them. We combined the clinical problems caused by the ER in in vitro maturation (IVM), and the mechanisms of ER have been identified by single-cell RNA-seq. This article systematically reviews the functions of ER and provides a reference for assisted reproductive technology (ART) research.

Unraveling the Role of Adiponectin Receptors in Obesity-Related Breast Cancer

Obesity has a noteworthy role in breast tumor initiation and progression. Among the mechanisms proposed, the most validated is the development of chronic low-grade inflammation, supported by immune cell infiltration along with dysfunction in adipose tissue biology, characterized by an imbalance in adipocytokines secretion and alteration of their receptors within the tumor microenvironment. Many of these receptors belong to the seven-transmembrane receptor family, which are involved in physiological features, such as immune responses and metabolism, as well as in the development and progression of several malignancies, including breast cancer. These receptors are classified as canonical (G protein-coupled receptors, GPCRs) and atypical receptors, which fail to interact and activate G proteins. Among the atypical receptors, adiponectin receptors (AdipoRs) mediate the effect of adiponectin, the most abundant adipocytes-derived hormone, on breast cancer cell proliferation, whose serum levels are reduced in obesity. The adiponectin/AdipoRs axis is becoming increasingly important regarding its role in breast tumorigenesis and as a therapeutic target for breast cancer treatment. The objectives of this review are as follows: to point out the structural and functional differences between GPCRs and AdipoRs, and to focus on the effect of AdipoRs activation in the development and progression of obesity-dependent breast cancer.

A Longitudinal Study of the Relationship of Adiponectin with Reproduction in Infertile Women Undergoing IVF/ICSI Treatment, and an Experimental Study in Human Granulosa Cells

This study investigated the roles of adiponectin in IVF treatment during Phase I (the basal stage before gonadotropin administration), Phase II (approximately 8 days after gonadotropin administration), and Phase III (on the ovum pick-up day), as well as the effects of adiponectin on CYP19A1 and the FSH receptor (FSHR) mRNA expression in a human granulosa-like tumor cell line (KGN). In human subjects (a longitudinal study, n = 30), blood samples were collected in all phases, while follicular fluid (FF) was only collected in Phase III. The participants were classified into successful and unsuccessful groups based on the determination of fetal heartbeats. KGN cells were treated with adiponectin/FSH/IGF-1 (an experimental study, n = 3). There was no difference in the adiponectin levels between successful and unsuccessful pregnancies in the FF (Phase III) and in serum (all phases), as well as among the three phases in both groups. Serum FSH (Phase I) was positively associated with serum adiponectin in the unsuccessful group, but it had a negative association in the successful group (all phases). Serum adiponectin and serum FSH (Phase I) were positively correlated in the unsuccessful group, whereas they were negatively correlated (all phases) in the successful group. The serum adiponectin levels (Phase III) were significantly higher than in the FF in unsuccessful pregnancies, but there was no difference in successful pregnancies. FF adiponectin concentrations were negatively correlated with serum LH in successful subjects. In KGN cells, adiponectin had no influence on CYP19A1 and FSHR mRNA expression. High adiponectin levels in serum compared to FF (Phase III) in unsuccessful subjects might negatively impact IVF treatment.

The Role of Adipokines in the Pathogenesis of Psoriasis

Psoriasis is a chronic and immune-mediated skin condition characterized by pro-inflammatory cytokines and keratinocyte hyperproliferation. Dendritic cells, T lymphocytes, and keratinocytes represent the main cell subtypes involved in the pathogenesis of psoriasis, while the interleukin-23 (IL-23)/IL-17 pathway enhances the disease progression. Human adipose tissue is an endocrine organ, which secretes multiple proteins, known as adipokines, such as adiponectin, leptin, visfatin, or resistin. Current evidence highlights the immunomodulatory roles of adipokines, which may contribute to the progression or suppression of psoriasis. A better understanding of the complexity of psoriasis pathophysiology linked with adipokines could result in developing novel diagnostic or therapeutic strategies. This review aims to present the pathogenesis of psoriasis and the roles of adipokines in this process.

Contribution of key elements of nutritional metabolism to the development of cystic ovarian disease in dairy cattle

The alteration of signaling molecules involved in the general metabolism of animals can negatively influence reproduction. In dairy cattle, the development of follicular cysts and the subsequent appearance of ovarian cystic disease (COD) often lead to decreased reproductive efficiency in the herd. The objective of this review is to summarize the contribution of relevant metabolic and nutritional sensors to the development of COD in dairy cows. In particular, we focus on the study of alterations of the insulin signaling pathway, adiponectin, and other sensors and metabolites relevant to ovarian functionality, which may be related to the development of follicular persistence and follicular formation of cysts in dairy cattle. The results of these studies support the hypothesis that systemic factors could alter the local scenario in the follicle, generating an adverse microenvironment for the resumption of ovarian activity and possibly leading to the persistence of follicles and to the development and recurrence of COD.

Novel variants associated with adiponectin-related traits in Awassi ewes

Background

Adipose tissue secretes adiponectin (ADIPOQ), a hormone related to fat oxidation, glucose metabolism, and reproduction. The polymorphism of adiponectin is associated with productive traits in domestic animals. Thus, this study investigated the association of adiponectin gene polymorphism with lipid profile and reproductive hormones in Awassi ewe. In this study, 200 ewes between the ages of 2.5 and 5 years, neither pregnant nor lactating, were included. To determine the lipid profile and reproductive hormones, sera were separated from the blood. DNA extraction, genotyping, and sequencing reactions were used to verify the variants in the amplified fragments (exon 1).

Results

Three genotypes, CC, CA, and AA, were identified from 368 bp amplicons (exon 1). A sequencing reaction revealed a novel mutation, c.198473337C > A, in the CA genotype. The results revealed significant differences (P ≤ 0.05) in cholesterol and HDL levels in the AA genotype than CC and CA genotypes. The AA genotype had higher estradiol and progesterone levels (50.52 ± 0.64) (pg/ml) and (7.10 ± 0.04) (ng/ml), respectively, than those with the CC and CA genotypes.

Conclusions

These results conclude that the ADIPOQ gene affects lipid profiles and sex hormone levels in Awassi sheep. Choosing sheep that are polymorphic for the ADIPOQ gene should be a future study, as this gene could be linked to high prolificacy.

Short communication: Photoperiod impacts ovarian extracellular matrix and metabolic gene expression in Siberian hamsters

Ovarian cyclicity is variable in adult Siberian hamsters (Phodopus sungorus), who respond to long breeding season photoperiods with follicle development and ovulation, while short photoperiods typical of the non-breeding season induce gonadal atrophy. Recent RNAseq results identified ovarian matrix components and regulators of metabolism as differentially regulated by photoperiod; however, the impact of photoperiod across a full cycle of ovarian regression and recrudescence had not been explored for additional regulators of ovarian metabolism and extracellular matrix components. We hypothesized that matrix and metabolism-related genes would be expressed differentially across photoperiods that mimic breeding and non-breeding season daylengths. Hamsters were housed in one of four photoperiod groups: long day (16 h of light per day: 8 h of dark; LD, controls), short day regressed (8 L:16D; SD, regressed), and females exposed to SD then transferred to LD to stimulate return of ovarian function for 2 (early recrudescence), or 8 (late recrudescence) weeks. Plasma leptin concentrations along with expression of ovarian versican and liver-receptor homolog-1/Nr582 mRNA decreased in SD compared to LD and late recrudescence, while vimentin mRNA expression peaked in early and late recrudescence. Ovarian expression of fibronectin and extracellular matrix protein-1 was low in LD ovaries and increased in regressed and recrudescing groups. Expression of hyaluronidase-2, nectin-2, liver-X receptors-α and-β, and adiponectin mRNA peaked in late recrudescence, with no changes noted for adiponectin receptor-1 and -2. The results offer a first look at the parallels between expression of these genes and the dynamic remodeling that occurs during ovarian regression and recrudescence.

The adiponectin receptor agonist, AdipoRon, promotes reproductive hormone secretion and gonadal development via the hypothalamic-pituitary-gonadal axis in chickens

Adiponectin is a key hormone secreted by fat tissues that has multiple biological functions, including regulating the energy balance and reproductive system by binding to its receptors AdipoR1 and AdipoR2. This study investigated the correlation between the levels of adiponectin and reproductive hormones in the hypothalamic-pituitary-ovarian (HPO) axis of laying hens at 4 different developmental stages (15, 20, 30, and 68 wk) and explored the effects of AdipoRon (an activator of adiponectin receptors) on the hypothalamic-pituitary-gonadal (HPG) axis and follicle and testicular Leydig cells in vitro and in vivo. The results demonstrated that the adiponectin level was significantly correlated with that of reproductive hormones in the HPO axis (e.g., GnRH, FSH, LH, and E2) in laying hens at 4 different ages. Moreover, AdipoRon could promote the expression of AdipoR1 and AdipoR2 and the secretion of reproductive hormones in the HPG axis, including GnRH, FSH, LH, P4, and T. AdipoRon could also upregulate the expression of genes related to follicular steroidogenesis (STAR, CYP19A1, CYP17A1, and CYP11A1), hepatic lipid synthesis (OVR, MTP), follicular lipid uptake (PPAR-g), and follicular angiogenesis (VEGFA1, VEGFA2, VEGFR1, ANGPT1, ANGPT2, TEK) in the oviposition period, and all of these findings were consistent with the results obtained from in vitro experiments after the transfection of small white follicles (SWFs) with AdipoRon. Furthermore, the results suggest that AdipoRon increases the diameter of testicular seminiferous tubules, the number of spermatogenic cells and sperm production in vivo and enhances the expression of AdipoR1, AdipoR2 and steroid hormones in vitro. Collectively, the findings suggest that AdipoRon could facilitate the expression and secretion of reproductive hormones in the HPG axis by activating its receptors and then improve the growth and development of follicles and testes in chickens.

Aclonifen could induce implantation failure during early embryonic development through apoptosis of porcine trophectoderm and uterine luminal epithelial cells

Aclonifen is a diphenyl-ether herbicide that is used to control the growth of weeds while growing crops such as corn and wheat. Although the biochemical effects of aclonifen are well characterized, including its ability to inhibit protoporphyrinogen oxidase and carotenoid synthesis, the toxicity of aclonifen in embryonic implantation and development during early pregnancy, has not been reported. Thus, in this study, we investigated the potential interference of aclonifen in embryonic implantation using porcine trophectoderm (pTr) and uterine luminal epithelial (pLE) cells isolated during implantation period of early pregnancy. Cell viability in both pTr and pLE cells significantly decreased in a dose-dependent manner following aclonifen treatment. Moreover, the proportion of cells in the sub-G1 phase of the cell cycle gradually increased upon treatment with increasing concentrations of aclonifen, which in turn led to an increase in the number of apoptotic cells, as determined by annexin V and propidium iodide staining. Aclonifen treatment caused mitochondrial dysfunction by increasing the depolarization of the mitochondrial membrane potential and the mitochondrial calcium concentration. Aclonifen inhibited cell mobility by suppressing the expression of implantation-related genes in pTr and pLE cells. To explore the underlying mechanism, we evaluated the phosphorylation of PI3K and MAPK signaling molecules. The phosphorylation of AKT, S6, JNK, and ERK1/2 were significantly increased by aclonifen. Collectively, our results suggest that aclonifen may interrupt implantation during early pregnancy by disrupting maternal-fetal interaction.

The Complex Roles of Adipokines in Polycystic Ovary Syndrome and Endometriosis

Polycystic ovary syndrome (PCOS) and endometriosis are frequent diseases of the female reproductive tract causing high morbidity as they can significantly affect fertility and quality of life. Adipokines are pleiotropic signaling molecules secreted by white or brown adipose tissues with a central role in energy metabolism. More recently, their involvement in PCOS and endometriosis has been demonstrated. In this review article, we provide an update on the role of adipokines in both diseases and summarize previous findings. We also address the results of multi-omics approaches in adipokine research to examine the role of single nucleotide polymorphisms (SNPs) in genes coding for adipokines and their receptors, the secretome of adipocytes and to identify epigenetic alterations of adipokine genes that might be conferred from mother to child. Finally, we address novel data on the role of brown adipose tissue (BAT), which seems to have notable effects on PCOS. For this review, original research articles on adipokine actions in PCOS and endometriosis are considered, which are listed in the PubMed database.

Adipokinesand Ghrelin Rolein Regulation of Ovarian Function in Obesity

There is a great worldwide trend in the incidence of obesity, which is increasing with each passing year among all populations, including women of reproductive age. Given the impressive list of diseases associated with obesity, as well as the negative inverse correlation of the severity of obesity with fertility, this problem is global not only in the social sphere, but it also becomes demographically significant.

Along with other pathogenetic mechanisms leading to persistent anovulation, an imbalance in adipokine production by adipose tissue can also serve as one of the important links in the development of reproductive dysfunction. Despite apparent interest in this topic, a large number of previously discovered adipokines are still not studied. Among adipokines, the effects of adiponectin and leptin on reproductive function are best known. Alterations in adiponectin and leptin levels can affect hypothalamic-pituitary-gonadal signaling, folliculogenesis, oogenesis and steroidogenesis. In addition, leptin is involved in the initiation of puberty, regulation of the menstrual cycle, and changes the balance between proliferation and apoptosis in ovarian cells. The leading causes of reduced fertility, infertility, and IVF failure in obese patients are mechanisms that promote the formation of chronic anovulation, delay the maturation of oocytes, reduce their quality, and/or lead to changes in endometrial susceptibility. These effects can be caused by an imbalance in the concentrations of leptin and adiponectin (leptin excess and adiponectin deficiency), lead to endometrial dysfunction, disruption of implantation and early embryogenesis. These changes, in turn, can affect just as the likelihood of spontaneous conception, so the effectiveness of assisted reproductive technologies and subsequent gestation.

Thus, the study of potential pathogenetic pathways of fertility regulation in obesity, one of which is the subject of this review, is an important area for further study.

Plasma Complement C1q/tumor necrosis factor-related protein 15 concentration is associated with polycystic ovary syndrome

Polycystic ovarian syndrome (PCOS) is a common poignant endocrine disorder affecting women, posing a close association with metabolic syndrome and obesity. Existing literature characterizes PCOS with deranged levels of several adipokines and myokines. CTRP15 is a paralogue of adiponectin, mainly expressed by skeletal muscles, and plays a key role in insulin, glucose, and lipid metabolism. In the current study, we aim to determine the circulating levels of CTRP15 and evaluate its association with cardiometabolic and inflammatory parameters in PCOS women. This case-control study included 120 PCOS patients (60 Recurrent pregnancy loss (RPL) and 60 infertile (inf) PCOS) and 60 healthy non-PCOS controls. Serum levels of hs-CRP were measured by commercial kits, while serum levels of adiponectin and CTRP15 were determined using the ELISA technique. Serum levels of CTRP15 were significantly elevated in PCOS-RPL and PCOS-inf subgroups when compared to controls (94.80 ± 27.08 and 87.77 ± 25.48 vs. 54.78 ± 15.45, both P < 0.001). Moreover, serum adiponectin was considerably lower in the PCOS group and subgroups (P < 0.001), while serum hs-CRP, fasting insulin, HOMA-IR, and free testosterone were significantly higher when compared to the non-PCOS group (P < 0.05). Furthermore, CTRP15 closely associated with FSH, HOMA-IR, hs-CRP, and BMI. These results highlight a possible involvement of CTRP15 in the pathogenesis of PCOS. The elevated levels of CTRP15 might be a compensatory mechanism for the metabolic dysregulations (excess adiposity, insulin resistance, metaflammation) associated with the syndrome. Nevertheless, future studies are necessary to unravel the underlying mechanism.

Role of Leptin and Adiponectin in Endometrial Cancer

Endometrial cancer is the most common malignancy of the female genital tract. Obesity is a strong risk factor for endometrial cancer. Adipose tissue is an active endocrine organ that synthesizes biologically active cytokine peptides, called adipokines. Adiponectin and leptin are the main cytokines of adipose tissue, which may influence the development of metabolic diseases and carcinogenesis. In this scenario, we describe the role of leptin and adiponectin in the development of endometrial cancer. A better understanding of the signalling pathway of these cytokines in endometrial cancerogenesis will provide an opportunity for effective target therapy and may be usable in fertility-sparing treatment. In the future, clinical trials focusing on adipokines, molecular biology, and genetics of the tumour will be needed.

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.

The Influence of Diet on Ovulation Disorders in Women—A Narrative Review

Female infertility is commonly due to ovulation disorders. They are mostly related to polycystic ovary syndrome, which is currently viewed as one of the most common endocrine disorders in women of reproductive age. Ovulation-related female fertility is influenced by multiple factors which may include: age, smoking cigarettes, stress, use of psychoactive substances, and physical activity. Moreover, diet-related factors play an important role in the regulation of ovulation. Dietary components that exert a positive influence on ovulation include: carbohydrate products with low glycemic index, plant protein, monounsaturated and polyunsaturated fatty acids, folic acid, vitamin D, antioxidants, and iron. A diet based on the structure of the Mediterranean diet also seems beneficial. Components that have a negative influence mostly include high glycemic index carbohydrates, large amounts of animal protein, saturated fatty acids, and trans fatty acids, which are typically found in the Western model of nutrition. Due to the paucity of studies that presented a direct link between nutrition and the risk of anovulatory infertility, this study aimed to summarize the most recent research on the influence of dietary factors on ovulation disorders and indicate the possibilities of future research.

Seminal Levels of Omentin-1/ITLN1 in Inflammatory Conditions Related to Male Infertility and Localization in Spermatozoa and Tissues of Male Reproductive System

Purpose

Omentin-1/intelectin (ITLN)1 is an adipocytokine with both anti-inflammatory and anti-oxidative stress properties, and little is known about its role in male reproduction. This study was aimed at exploring the relationships among omentin-1/ITLN1, semen parameters and F₂-isoprostanes (F₂-IsoPs), a maker of oxidative stress, in groups of patients affected by different pathologies. In addition, omentin-1/ITLN1 immunolocalization was assessed in ejaculated spermatozoa and in tissues of male reproductive system.

Patients and Methods

Semen samples of infertile patients with varicocele (n = 27), genitourinary infections (n = 17), idiopathic infertility (n = 15) and fertile men (n = 21) were analyzed following WHO guidelines, and seminal plasma were used to determine omentin-1/ITLN1 by ELISA and F₂-IsoP levels by gas chromatography/negative-ion chemical ionization tandem mass spectrometry. Omentin-1/ITLN1 was localized in human sperm and in the tissue of male reproductive system.

Results

Considering all participants, F₂-IsoP and omentin-1/ITLN1 levels were positively correlated (p = 0.000), and both these indices were negatively correlated with sperm parameters. Infertile patients showed lower sperm parameters than fertile ones; varicocele and infection groups had significantly increased levels of F₂-IsoPs (both p = 0.000) and omentin-1/ITLN1 (p = 0.000 and p = 0.001, respectively). Omentin-1/ITLN1 signal was located as a spot in the connecting piece (in 43.5% of cases midpiece was also labeled) of sperm from fertile men and in cytoplasmic residue and in the entire tail in sperm of patients with varicocele and genitourinary infections. A focal omentin-1/ITLN1 immunolabelling was evident in the basal area of epididymal tubule, and a diffuse signal was present in the seminal vesicle epithelium.

Conclusion

Semen omentin-1/ITLN1 originates from seminal vesicles, its levels increase in inflammatory conditions and are negatively correlated with sperm parameters. For this reason, a sort of protective role of omentin-1/ITLN1 can be postulated, as this adipokine shows anti-inflammatory properties also in many other biological systems.

Impact of metabolic disorders on endometrial receptivity in patients with polycystic ovary syndrome

The present study investigated the expression of endometrial receptivity-related molecules in patients with polycystic ovary syndrome (PCOS) and different androgen status, insulin resistance (IR) levels, and body mass indexes (BMI) to identify the mechanism underlying their effects on pregnancy outcomes. The present study recruited 43 participants from November 2020 to January 2021, which were classified into five groups: i) Hyperandrogenemia (HA) combined with impaired glucose tolerance group (n=8); ii) HA combined with diabetes mellitus group (n=8); iii) HA combined with non-IR (NIR) group (n=10); iv) non-HA (NHA) androgen combined with IR group (n=8); and v) NHA combined with NIR group (n=9). In addition, according to their BMIs, patients were sub-grouped into lean/normal (n=27), overweight (n=8) or obese (n=8) groups. The mRNA expression levels of endometrial receptivity-related molecules were detected using reverse transcription-quantitative PCR. In addition, flow cytometry was used to determine the phenotype and percentage of uterine natural killer cells (uNK). According to the results, patients with PCOS and IR status, HA and obesity (BMI ≥24 kg/m²) demonstrated significantly decreased mRNA expression levels of adiponectin, adiponectin receptor (AdipoR)1, AdipoR2, adapter protein containing PH domain, PTB domain and leucine zipper motif 1, estrogen receptor (ER) α, ERβ, progesterone receptor (PR), IL-15, integrin β3 avβ3, and insulin-like growth factor binding protein-1, but increased mRNA expression levels of IL-6 and IL-8 compared with NHA + NIR group or lean/normal group, respectively. In addition, obese patients with PCOS demonstrated increased mRNA expression levels of PR compared with overweight patients. This suggested that insulin resistant status, HA, and obesity could alter the endometrial receptivity of patients with PCOS, which may explain poorer embryo implantation and pregnancy outcomes in clinics.

The Protective Effects of Trans-Anethole against Polycystic Ovary Syndrome Induced Histopathological and Metabolic Changes in Rat

Aim of the study was to evaluate the protective effects of trans-anethole, against polycystic ovary syndrome (PCOS) induced histopathological and biochemical changes in female Wister rats.<br />Materials and Methods: In this experimental study, forty-eight animals were randomly assigned into 6 groups: control; PCOS; PCOS+trans-anethole (20, 40, 80 mg/kg); and PCOS+metformin (300 mg/kg). Testosterone (1 mg/kg/day) was injected intraperitoneally for 35 days to induce PCOS. After PCOS induction, animals were treated by transanethole and metformin (30 days oral gavage). Finally, serum oxidative stress and insulin levels as well as histological changes in ovaries, kidneys and liver were evaluated.<br />Results: In PCOS group, the serum level of malondialdehyde (MDA) was 1.391 ± 0.18 mmol/L and significantly<br />increased (P=0.000) compared to the control group with the MDA level of 0.35 ± 0.08. Meanwhile the activity of<br />superoxide dismutase (SOD) and catalase (CAT), and total thiol levels were significantly decreased (P=0.000 for all<br />groups), compared to the control group. In the trans-anethole (80 mg/kg) treated group, insulin (P=0.000) and MDA<br />(P=0.000) levels were significantly decreased while total thiol (P=0.001) and activity of SOD (P=0.000) and CAT<br />(P=0.007) were significantly increased compared to the PCOS group. In the metformin treated group the insulin level<br />(P=0.03) decreased compared to the PCOS group. Histological evaluation showed multiple cysts in the ovarian tissue,<br />an increase in inflammatory cells in the liver, and a loss of order in the structure of the tubules and glomeruli of the<br />kidney in the PCOS group. Tissue damage was reduced in the trans-anethole treated group.<br />Conclusion: Tarns-anethole at a dose of 80 mg/kg improved metabolic status, oxidative stress, liver and kidney damage<br />as well as the cystic mass of ovarian tissue. To understand the exact protective effects of trans-anethole in PCOS,<br />more experimental or clinical studies are suggested.

Female obesity and infertility: outcomes and regulatory guidance

Obesity has been associated with reduced fertility, although the dynamics and mechanisms which link excess weight to reduced fertility are not yet fully clarified. Obese women, especially those with central obesity, are less likely to conceive per cycle. Obese women suffer from perturbations of the hypothalamus-pituitary-ovary axis, disturbances of the menstrual cycle and are up to three times more likely to suffer from oligo/anovulation. A delicate hormonal balance regulates follicular development and the maturation of oocytes and it has been observed that obesity can alter the hormonal environment: adipocytes, in fact, are responsible for the production of a hormone called leptin (present in high quantities in obese women) which has been associated with reduced fecundity. In addition to compromising ovulation, obesity negatively affects the development and implantation of the endometrium. The expression of polycystic ovary syndrome (PCOS) is regulated, in part, by weight, so obese women with PCOS often have a more severe phenotype and higher subfertility rates. Furthermore, obesity impairs women's response to medically assisted procreation (MAP) treatments. The authors have set out to delineate a broad-ranging overview of obesity's impact on female fertility, by drawing upon sources spanning the 1994-2022 period. Assisted reproductive technology (ART) procedures are also discussed as they relate to obese patients. In addition the dynamics by which maternal obesity reportedly affects fetal, neonatal and child development have also been briefly enunciated.

Supraphysiological Role of Melatonin Over Vascular Dysfunction of Pregnancy, a New Therapeutic Agent?

Hypertension can be induced by the disruption of factors in blood pressure regulation. This includes several systems such as Neurohumoral, Renin-angiotensin-aldosterone, the Circadian clock, and melatonin production, which can induce elevation and non-dipping blood pressure. Melatonin has a supraphysiological role as a chronobiotic agent and modulates vascular system processes via pro/antiangiogenic factors, inflammation, the immune system, and oxidative stress regulation. An elevation of melatonin production is observed during pregnancy, modulating the placenta and fetus’s physiological functions. Their impairment production can induce temporal desynchronization of cell proliferation, differentiation, or invasion from trophoblast cells results in vascular insufficiencies, elevating the risk of poor fetal/placental development. Several genes are associated with vascular disease and hypertension during pregnancy via impaired inflammatory response, hypoxia, and oxidative stress, such as cytokines/chemokines IL-1β, IL-6, IL-8, and impairment expression in endothelial cells/VSMCs of HIF1α and eNOS genes. Pathological placentas showed differentially expressed genes (DEG), including vascular genes as CITED2, VEGF, PL-II, PIGF, sFLT-1, and sENG, oncogene JUNB, scaffolding protein CUL7, GPER1, and the pathways of SIRT/AMPK and MAPK/ERK. Additionally, we observed modification of subunits of NADPH oxidase and extracellular matrix elements, i.e., Glypican and Heparanase and KCa channel. Mothers with a low level of melatonin showed low production of proangiogenic factor VEGF, increasing the risk of preeclampsia, premature birth, and abortion. In contrast, melatonin supplementation can reduce systolic pressure, prevent oxidative stress, induce the activation of the antioxidants system, and lessen proteinuria and serum level of sFlt-1. Moreover, melatonin can repair the endothelial damage from preeclampsia at the placenta level, increasing PIGF, Nrf-2, HO-1 production and reducing critical markers of vascular injury during the pregnancy. Melatonin also restores the umbilical and uterine blood flow after oxidative stress and inhibits vascular inflammation and VCAM-1, Activin-A, and sEng production. The beneficial effects of melatonin over pathological pregnancies can be partially observed in normal pregnancies, suggesting the dual role of/over placental physiology could contribute to protection and have therapeutic applications in vascular pathologies of pregnancies in the future.

Post-translational protein deimination signatures in sea lamprey (Petromyzon marinus) plasma and plasma-extracellular vesicles

Lampreys are a jawless vertebrate species belonging to an ancient vertebrate lineage that diverged from a common ancestor with humans ~500 million years ago. The sea lamprey (Petromyzon marinus) has a filter feeding ammocoete larval stage that metamorphoses into a parasitic adult, feeding both on teleost and elasmobranch fish. Lampreys are a valuable comparative model species for vertebrate immunity and physiology due to their unique phylogenetic position, unusual adaptive immune system, and physiological adaptions such as tolerance to salinity changes and urea. Peptidylarginine deiminases (PADs) are a phylogenetically conserved enzyme family which catalyses post-translational deimination/citrullination in target proteins, enabling proteins to gain new functions (moonlighting). The identification of deiminated protein targets in species across phylogeny may provide novel insights into post-translational regulation of physiological and pathophysiological processes. Extracellular vesicles (EVs) are membrane vesicles released from cells that carry cargos of small molecules and proteins for cellular communication, involved in both normal and pathological processes. The current study identified deimination signatures in proteins of both total plasma and plasma-EVs in sea lamprey and furthermore reports the first characterisation of plasma-EVs in lamprey. EVs were poly-dispersed in the size range of 40-500 nm, similar to what is observed in other taxa, positive for CD63 and Flotillin-1. Plasma-EV morphology was confirmed by transmission electron microscopy. Assessment of deimination/citrullination signatures in lamprey plasma and plasma-EVs, revealed 72 deimination target proteins involved in immunity, metabolism and gene regulation in whole plasma, and 37 target proteins in EVs, whereof 24 were shared targets. Furthermore, the presence of deiminated histone H3, indicative of gene-regulatory mechanisms and also a marker of neutrophil extracellular trap formation (NETosis), was confirmed in lamprey plasma. Functional protein network analysis revealed some differences in KEGG and GO pathways of deiminated proteins in whole plasma compared with plasma-EVs. For example, while common STRING network clusters in plasma and plasma-EVs included Peptide chain elongation, Viral mRNA translation, Glycolysis and gluconeogenesis, STRING network clusters specific for EVs only included: Cellular response to heat stress, Muscle protein and striated muscle thin filament, Nucleosome, Protein processing in endoplasmic reticulum, Nucleosome and histone deacetylase complex. STRING network clusters specific for plasma were: Adipokinetic hormone receptor activity, Fibrinogen alpha/beta chain family, peptidase S1A, Glutathione synthesis and recycling-arginine, Fructose 1,6-bisphosphate metabolic process, Carbon metabolism and lactate dehydrogenase activity, Post-translational protein phosphorylation, Regulation of insulin-like growth factor transport and clotting cascade. Overall, for the EV citrullinome, five STRING network clusters, 10 KEGG pathways, 15 molecular GO pathways and 29 Reactome pathways were identified, compared with nine STRING network clusters, six KEGG pathways, two Molecular GO pathways and one Reactome pathway specific for whole plasma; while further pathways were shared. The reported findings indicate that major pathways relevant for immunity and metabolism are targets of deimination in lamprey plasma and plasma-EVs, with some differences, and may help elucidating roles for the conserved PAD enzyme family in regulation of immune and metabolic function throughout phylogeny.

Adiponectin: a pleiotropic hormone with multifaceted roles

Adipose tissue mostly composed of different types of fat is one of the largest endocrine organs in the body playing multiple intricate roles including but not limited to energy storage, metabolic homeostasis, generation of heat, participation in immune functions and secretion of a number of biologically active factors known as adipokines. The most abundant of them is adiponectin. This adipocite-derived hormone exerts pleiotropic actions and exhibits insulin-sensitizing, antidiabetic, anti-obesogenic, anti-inflammatory, antiatherogenic, cardio- and neuroprotective properties. Contrariwise to its protective effects against various pathological events in different cell types, adiponectin may have links to several systemic diseases and malignances. Reduction in adiponectin levels has an implication in COVID-19-associated respiratory failure, which is attributed mainly to a phenomenon called 'adiponectin paradox'. Ample evidence about multiple functions of adiponectin in the body was obtained from animal, mostly rodent studies. Our succinct review is entirely about multifaceted roles of adiponectin and mechanisms of its action in different physiological and pathological states.

The Association between Disordered Eating Behavior and Body Image Biological Maturation and Levels of Adipocytokines in Preadolescent Girls: The Healthy Growth Study

During puberty, rapid, complex hormonal, physical and cognitive changes occur that affect body image and eating behavior. The aim of this cross-sectional study, a secondary analysis of data from the Greek Healthy Growth Study, was to explore associations of disordered eating behaviors and body image in 1206 10–12-year-old girls during pubertal maturation, with serum leptin and adiponectin levels, according to body mass index (BMI). Eating behavior and disordered eating were assessed with the Dutch Eating Behavior Questionnaire (DEBQ) and the Children Eating Attitudes Test Questionnaire (ChEAT), respectively. Associations of components of DEBQ and ChEAT with maturation according to Tanner Stage (TS) and levels of leptin and adiponectin were explored by univariate and multivariate regression analysis. Adiponectin levels in girls at TS 1 were positively associated with the “social pressure to eat” score of ChEAT. Leptin levels in girls at TS 4 were positively correlated with the “restraint eating” score of DEBQ, and the “dieting”, “body image” and “food awareness” scores of ChEAT. After adjustment for TS and BMI, only “body image” and leptin remained significant. Further research may shed light on how these hormonal changes affect eating behaviors at various pubertal stages, contributing to “TS-specific” preventive strategies for eating disorders in girls.

Insulin resistance and potential modulators of ovarian reserve in young reproductive-aged women with obesity and type 1 diabetes

INTRODUCTION

Both obesity and diabetes play a significant role in reproductive disorders in women and insulin resistance (IR) is a confirmed trait d'union. We evaluated the relationship between IR and an established ovarian reserve biomarker such as anti-mullerian hormone (AMH) together with other potential modulators of ovarian physiology (adiponectin and kisspeptin) in young reproductive-aged group women with obesity and type 1 diabetes (T1D).

PATIENTS AND METHODS

We recruited 32 female youths: 14 of them presented with T1D (14.6 ± 2.6 years) and 18 with obesity (15.1 ± 2.6 years). The control group included 20 age-matched normal weight females. Each patient underwent physical examination and hormonal assessment. AMH, kisspeptin and adiponectin levels were also measured. IR was calculated as the homeostasis model assessment for insulin resistance (HOMA-IR) and the glucose disposal rate (eGDR) in patients with obesity and with T1D, respectively.

RESULTS

adiponectin and kisspeptin levels were significantly different into groups (p ≤ .001), whereas AMH levels were not. Adiponectin values were higher in controls compared to patients with obesity (p < .001) and T1D (p = .02). Kisspeptin levels were lower in controls compared to patients with obesity (p = .001), without reaching statistical significance when compared to T1D (p = .06). IR was associated with lower adiponectin and higher kisspeptin levels (p < .001 and p = .02, respectively), but not with AMH.

CONCLUSIONS

IR displays a relationship with adiponectin and kisspeptin in young reproductive-aged women with obesity and T1D. Interventions to correct IR in adolescents could be part of an early approach to prevent reproductive disorders and to promote factors associated with longevity in adult women.

Adipokine, gut and thyroid hormone responses to probiotic application in chukar partridges (Alectoris chukar) exposed to heat stress

The aim of this study was to investigate the effect of Lactobacillus reuteri E81 (LRE) probiotic supplementation on heat stress responses in chukar partridges (Alectoris chukar). The birds were divided into two groups, one of which was exposed to heat stress (HS). Within each group, four subgroups, each including 64 birds, were created for the three treatment doses (200, 400 or 600 mg/kg) of LRE and the control. The experiment was started with day-old birds, kept at a temperature of 25 °C or 37 °C. After a 7-day adjustment period, the LRE supplementation lasted for 35 days. The levels of different adipokines, including visfatin (VF), adiponectin (ADP), chemerin (CHEM), as well as the concentration of plasma citrulline (CIT) and the levels of thyroid hormones (T3 and T4) and thyroid-stimulating hormone (TSH) in the blood were measured at 21 and 42 days of age. A significant correlation (P < 0.01) was found between LRE supplementation and the decrease in serum VF, ADP, CIT, T3 and T4 levels in partridges exposed to HS. On the other hand, no significant relationship was found between LRE supplementation and the serum CHEM and TSH levels (P > 0.05). We concluded that the addition of 600 mg/kg LRE is beneficial in preventing intestinal damage and inflammation provoked by HS.

Maternal adiponectin prevents visceral adiposity and adipocyte hypertrophy in prenatal androgenized female mice

Hyperandrogenism is the main characteristic of polycystic ovary syndrome, which affects placental function and fetal growth, and leads to reproductive and metabolic dysfunction in female offspring. Adiponectin acts on the placenta and may exert endocrine effects on the developing fetus. This study aims to investigate if maternal and/or fetal adiponectin can prevent metabolic and reproductive dysfunction in prenatal androgenized (PNA) female offspring. Adiponectin transgenic (APNtg) and wild-type dams received dihydrotestosterone/vehicle injections between gestational days 16.5-18.5 to induce PNA offspring, which were followed for 4 months. Offspring from APNtg dams were smaller than offspring from wild-type dams, independent of genotype. Insulin sensitivity was higher in wild-type mice from APNtg dams compared to wild-types from wild-type dams, and insulin sensitivity correlated with fat mass and adipocyte size. PNA increased visceral fat% and adipocyte size in wild-type offspring from wild-type dams, while wild-type and APNtg offspring from APNtg dams were protected against this effect. APNtg mice had smaller adipocytes than wild-types and this morphology was associated with an increased expression of genes regulating adipogenesis (Ppard, Pparg, Cebpa, and Cebpb) and metabolism (Chrebp and Lpl). Anogenital distance was increased in all PNA-exposed wild-type offspring, but there was no increase in PNA APNtg offspring, suggesting that adiponectin overexpression protects against this effect. In conclusion, elevated adiponectin levels in utero improve insulin sensitivity, reduce body weight and fat mass gain in the adult offspring and protect against PNA-induced visceral adiposity. In conclusion, these data suggest that PNA offspring benefit from prenatal adiponectin supplementation.