Adipose tissue and reproductive health

Egg white hydrolysate protects white adipose tissue against metabolic insult in deoxycorticosterone acetate-salt rats

The purpose of this study was to investigate the effect of an egg white hydrolysate (EWH) to protect white adipose tissue damage from cardiometabolic changes induced by severe hypertension. Male Wistar rats were uninephrectomised and divided: SHAM (weekly subcutaneous vehicle (mineral oil + propylene glycol, 1:1)), SHAM + EWH (subcutaneous vehicle plus EWH via gavage, 1 g/kg per day), DOCA (deoxycorticosterone acetate diluted in vehicle subcutaneously weekly in subsequent doses of 20 mg/kg -1st week, 12 mg/kg - 2–3th week, and 6 mg/kg -4–8th week, respectively, plus 1 % NaCl and 0·2 % KCl in drinking water), and DOCA + EWH. Body weight gain, food and water intake, glucose and lipid metabolism were evaluated. Oxidative stress was assessed by biochemical assay and immunofluorescence for NOX-1, nuclear factor kappa B (NFκB), and caspase-3 in retroperitoneal white adipose tissue (rtWAT). Proinflammatory cytokines (IL-6 and 1β), CD163+ macrophage infiltration, and immunohistochemistry for TNFα and uncoupling protein-1 were evaluated, as well as histological analysis on rtWAT. Glutathione peroxidase and reductase were also determined in plasma. EWH showed hypocholesterolemic, antioxidant, anti-inflammatory, and anti-apoptotic properties in the arterial hypertension DOCA-salt model. The results demonstrated the presence of functional changes in adipose tissue function by a decrease in macrophage infiltration and in the fluorescence intensity of NFκB, NOX-1, and caspase-3. A reduction of proinflammatory cytokines and restoration of antioxidant enzymatic activity and mitochondrial oxidative damage by reducing uncoupling protein-1 fluorescence intensity were also observed. EWH could be used as a potential alternative therapeutic strategy in the treatment of cardiometabolic complications associated with malignant secondary arterial hypertension.

Association between BMI and age at menarche or spermarche among both sexes: Findings from six successive national surveys in China

Background

To explore trends of the association between body mass index (BMI) and age at menarche or spermarche and its urban-rural disparities from 1995 to 2019.

Methods

A total of 912 753 children and adolescents - including 519 940 9-18 years old girls and 392 813 11-18 years old boys - were involved in six successive cross-sectional surveys conducted across 30 provinces in China from 1995 to 2019. Data on menarche and spermarche was collected using the status quo method, where same-gender physicians conducted face-to-face interviews to determine if children and adolescents had experienced their first menstrual cycle or ejaculation (yes/no). The median age at menarche or spermarche was estimated by probit analysis. Anthropometric measurements measured the height and weight of the study subjects. Children and adolescents were classified into thinness, normal range of weight, overweight, and obesity. t test was used to compare the differences in BMI between premenarchal and postmenarchal girls or prespermarcheal and postspermarcheal boys. Logistic regression was used to explore the associations between BMI/nutritional status and menarche or spermarche stratified by urban or rural residency status.

Results

From 1995 to 2019, BMI in all age groups growth over time, and the values of BMI among children and adolescents under 15 who had menarche or spermarche were more significant than those without menarche or spermarche. In 2019, for girls, thinness was associated with delayed menarche (odds ratio (OR) = 0.26; 95% confidence interval (CI) = 0.24-0.28), while overweight (OR = 1.99; 95% CI = 1.85-2.14) and obesity (OR = 2.20; 95% CI = 1.92-2.53) was associated with advanced menarche. For boys, thinness was associated with delayed spermarche (OR = 0.71; 95% CI = 0.65-0.78), overweight was associated with advanced spermarche (OR = 1.08; 95% CI = 1.01-1.15) while obesity had no association with spermarche. The OR between BMI and menarche in 1995 was 1.35 (95% CI = 1.33-1.37), which decreased to 1.19 (95% CI = 1.18-1.20) by 2019. The OR between BMI and spermarche in 1995 was 1.10 (95% CI = 1.09-1.11), which decreased to 1.02 (95% CI = 1.02-1.03) by 2019. The trends by urban-rural stratification were consistent with the total sample.

Conclusions

We have established a dose-response relationship between BMI and menarche in girls, whereas the association appears to be nonlinear in boys, and the associations were diminishing. Similar findings were observed in both urban and rural areas. Considering the dual adverse effects of obesity and early puberty on health, the results of this study suggest that sexual health education should be strengthened, especially among obese girls. Further research on the influencing factors and biological mechanisms of early puberty will be beneficial.

White adipocyte dysfunction and obesity-associated pathologies in humans

The prevalence of obesity and associated chronic diseases continues to increase worldwide, negatively impacting on societies and economies. Whereas the association between excess body weight and increased risk for developing a multitude of diseases is well established, the initiating mechanisms by which weight gain impairs our metabolic health remain surprisingly contested. In order to better address the myriad of disease states associated with obesity, it is essential to understand adipose tissue dysfunction and develop strategies for reinforcing adipocyte health. In this Review we outline the diverse physiological functions and pathological roles of human white adipocytes, examining our current knowledge of why white adipocytes are vital for systemic metabolic control, yet poorly adapted to our current obesogenic environment.

NOTCH1 as a Negative Regulator of Avian Adipocyte Differentiation: Implications for Fat Deposition

The NOTCH signaling pathway plays a pivotal role in diverse developmental processes, including cell proliferation and differentiation. In this study, we investigated whether this signaling molecules also contribute to avian adipogenesis. Using previous mRNA-seq datasets, we examined the expression of 11 signaling members during avian adipocyte differentiation. We found most members are down-regulated throughout differentiation (p < 0.05). As a representative, NOTCH1 was decreased in cultured chicken abdominal adipocytes during adipogenesis at mRNA and protein levels (p < 0.05). Moreover, using an overexpression plasmid for NOTCH1's intracellular domain (NICD1), as well as siRNA and DAPT to activate or deplete NOTCH1 in cells, we investigated the role of NOTCH1 in avian adipogenesis. Our findings illuminate that NOTCH1 activates the expression of HES1 and SOCS3 while it decreases NR2F2 and NUMB (p < 0.05), as well as inhibits oleic acid-induced adipocyte differentiation (p < 0.01). We further demonstrate that HES1, a downstream transcription factor activated by NOTCH1, also significantly inhibits adipogenesis by suppressing PPARγ and C/EBPα (p < 0.01). Collectively, these findings establish NOTCH1 as a negative regulator of avian adipocyte differentiation, unveiling NOTCH signaling as a potential target for regulating avian fat deposition.

The link between obesity and insulin resistance among children: Effects of key metabolites

BACKGROUND

Childhood obesity became a severe public health challenge, and insulin resistance (IR) was one of the common complications. Both obesity and IR were considered as the basis of metabolic disorders. However, it is unclear which common key metabolites are associated with childhood obesity and IR.

METHODS

The children were divided into normal weight and overweight/obese groups. Fasting blood glucose and fasting insulin were measured, and homeostasis model assessment of insulin resistance was calculated. Liquid chromatography-tandem mass spectrometry was applied for metabonomic analysis. Multiple linear regression analysis and correlation analysis explored the relationships between obesity, IR, and metabolites. Random forests were used to rank the importance of differential metabolites, and relative operating characteristic curves were used for prediction.

RESULTS

A total of 88 normal-weight children and 171 obese/overweight children participated in the study. There was a significant difference between the two groups in 30 metabolites. Childhood obesity was significantly associated with 10 amino acid metabolites and 20 fatty acid metabolites. There were 12 metabolites significantly correlated with IR. The ranking of metabolites in random forest showed that glutamine, tyrosine, and alanine were important in amino acids, and pyruvic-ox-2, ethylmalonic-2, and phenyllactic-2 were important in fatty acids. The area under the curve of body mass index standard deviation  score (BMI-SDS) combined with key amino acid metabolites and fatty acid metabolites for predicting IR was 80.0% and 76.6%, respectively.

CONCLUSIONS

There are common key metabolites related to IR and obese children, and these key metabolites combined with BMI-SDS could effectively predict the risk of IR.

Milestones in the journey towards addressing obesity; Past trials and triumphs, recent breakthroughs, and an exciting future in the era of emerging effective medical therapies and integration of effective medical therapies with metabolic surgery

The 21st century is characterized by an increasing incidence and prevalence of obesity and the burden of its associated comorbidities, especially cardiometabolic diseases, which are reaching pandemic proportions. In the late '90s, the "black box" of adipose tissue and energy homeostasis was opened with the discovery of leptin, transforming the adipose tissue from an "inert fat-storage organ" to the largest human endocrine organ and creating the basis on which more intensified research efforts to elucidate the pathogenesis of obesity and develop novel treatments were based upon. Even though leptin was eventually not proven to be the "standalone magic bullet" for the treatment of common/polygenic obesity, it has been successful in the treatment of monogenic obesity syndromes. Additionally, it shifted the paradigm of treating obesity from a condition due to "lack of willpower" to a disease due to distinct underlying biological mechanisms for which specific pharmacotherapies would be needed in addition to lifestyle modification. Subsequently, the melanocortin pathway proved to be an equally valuable pathway for the pharmacotherapy of obesity. Melanocortin receptor agonists have recently been approved for treating certain types of syndromic obesity. Other molecules- such as incretins, implicated in energy and glucose homeostasis- are secreted by the gastrointestinal tract. Glucagon-like peptide 1 (GLP-1) is the most prominent one, with GLP-1 analogs approved for common/polygenic obesity. Unimolecular combinations with other incretins, e.g., GLP-1 with gastric inhibitory polypeptide and/or glucagon, are expected to be approved soon as more effective pharmacotherapies for obesity and its comorbidities. Unimolecular combinations with other compounds and small molecules activating the receptors of these molecules are currently under investigation as promising future pharmacotherapies. Moreover, metabolic and bariatric surgery has also demonstrated impressive results, especially in the case of morbid obesity. Consequently, this broadening therapeutic armamentarium calls for a well-thought-after and well-coordinated multidisciplinary approach, for instance, through cardiometabolic expertise centers, that would ideally address effectively and cost-effectively obesity and its comorbidities, providing tangible benefits to large segments of the population.

Feeding neurons integrate metabolic and reproductive states in mice

Balance between metabolic and reproductive processes is important for survival, particularly in mammals that gestate their young. How the nervous system coordinates this balance is an active area of study. Herein, we demonstrate that somatostatin (SST) neurons of the tuberal hypothalamus alter feeding in a manner sensitive to metabolic and reproductive states in mice. Whereas chemogenetic activation of SST neurons increased food intake across sexes, ablation decreased food intake only in female mice during proestrus. This ablation effect was only apparent in animals with low body mass. Fat transplantation and bioinformatics analysis of SST neuronal transcriptomes revealed white adipose as a key modulator of these effects. These studies indicate that SST hypothalamic neurons integrate metabolic and reproductive cues by responding to varying levels of circulating estrogens to modulate feeding differentially based on energy stores. Thus, gonadal steroid modulation of neuronal circuits can be context dependent and gated by metabolic status.

Potential for NPY receptor-related therapies for polycystic ovary syndrome: an updated review

Polycystic ovary syndrome (PCOS) is a complex endocrine disease that can cause female infertility and bring economic burden to families and to society. The clinical and/or biochemical manifestations include hyperandrogenism, persistent anovulation, and polycystic ovarian changes, often accompanied by insulin resistance and obesity. Although its pathogenesis is unclear, PCOS involves the abnormal regulation of the hypothalamic-pituitary-ovarian axis and the abnormal activation of GnRH neurons. Neuropeptide Y (NPY) is widely distributed in the arcuate nucleus of the hypothalamus and functions as the physiological integrator of two neuroendocrine systems, one governing feeding and the other controlling reproduction. In recent years, an increasing number of studies have focused on the improvement of the reproductive and metabolic status of PCOS through the therapeutic application of NPY and its receptors. In this review, we summarize the central and peripheral regulation of NPY and its receptors in the development of PCOS and discuss the potential for NPY receptor-related therapies for PCOS.

Comparison of Adiponectin Levels in Anorexia Nervosa, Bulimia Nervosa, Binge-Eating Disorder, Obesity, Constitutional Thinness, and Healthy Controls: A Network Meta-Analysis

Adiponectin is a protein hormone that is produced and secreted primarily by adipose tissue. The levels of adiponectin in those with eating disorders, obesity, and healthy controls have been extensively studied. However, the general picture of the differences in adiponectin levels across the mentioned conditions is still unclear and fragmented. In this study, we pooled previous studies and performed a network meta-analysis to gain a global picture of comparisons of adiponectin levels across eating disorders, obesity, constitutional thinness, and healthy controls. Electronic databases were searched for anorexia nervosa, avoidant restrictive food intake disorder, binge-eating disorder, bulimia nervosa, healthy controls, night eating syndrome, obesity, and constitutional thinness in studies where adiponectin levels were measured. A total of 4262 participants from 50 published studies were included in the network meta-analysis. Adiponectin levels were significantly higher in participants with anorexia nervosa than in healthy controls (Hedges' g = 0.701, p < 0.001). However, adiponectin levels in constitutionally thin participants were not significantly different from those of healthy controls (Hedges' g = 0.470, p = 0.187). Obesity and binge-eating disorder were associated with significantly lower adiponectin levels compared to those of healthy controls (Hedges' g = -0.852, p < 0.001 and Hedges' g = -0.756, p = 0.024, respectively). The disorders characterized by excessive increases or decreases in BMI were associated with significant changes in adiponectin levels. These results suggest that adiponectin may be an important marker of severely disequilibrated homeostasis, especially in fat, glucose, and bone metabolisms. Nonetheless, an increase in adiponectin may not simply be associated with a decrease in BMI, as constitutional thinness is not associated with a significant increase in adiponectin.

Links between Childhood Obesity, High-Fat Diet, and Central Precocious Puberty

In recent years, the existing relationship between excess overweight and central precocious puberty (CPP) has been reported, especially in girls. Different nutritional choices have been associated with different patterns of puberty. In particular, the involvement of altered biochemical and neuroendocrine pathways and a proinflammatory status has been described in connection with a high-fat diet (HFD). In this narrative review, we present an overview on the relationship between obesity and precocious pubertal development, focusing on the role of HFDs as a contributor to activating the hypothalamus-pituitary-gonadal axis. Although evidence is scarce and studies limited, especially in the paediatric field, the harm of HFDs on PP is a relevant problem that cannot be ignored. Increased knowledge about HFD effects will be useful in developing strategies preventing precocious puberty in children with obesity. Promoting HFD-avoiding behavior may be useful in preserving children's physiological development and protecting reproductive health. Controlling HFDs may represent a target for policy action to improve global health.

Feeding Neurons Integrate Metabolic and Reproductive States in Mice

Trade-offs between metabolic and reproductive processes are important for survival, particularly in mammals that gestate their young. Puberty and reproduction, as energetically taxing life stages, are often gated by metabolic availability in animals with ovaries. How the nervous system coordinates these trade-offs is an active area of study. We identify somatostatin neurons of the tuberal nucleus (TNSST) as a node of the feeding circuit that alters feeding in a manner sensitive to metabolic and reproductive states in mice. Whereas chemogenetic activation of TNSST neurons increased food intake across sexes, selective ablation decreased food intake only in female mice during proestrus. Interestingly, this ablation effect was only apparent in animals with a low body mass. Fat transplantation and bioinformatics analysis of TNSST neuronal transcriptomes revealed white adipose as a key modulator of the effects of TNSST neurons on food intake. Together, these studies point to a mechanism whereby TNSST hypothalamic neurons modulate feeding by responding to varying levels of circulating estrogens differentially based on energy stores. This research provides insight into how neural circuits integrate reproductive and metabolic signals, and illustrates how gonadal steroid modulation of neuronal circuits can be context-dependent and gated by metabolic status.

Role of Hormones During Gestation and Early Development: Pathways Involved in Developmental Programming

Accumulating evidence suggests that an altered maternal milieu and environmental insults during the intrauterine and perinatal periods of life affect the developing organism, leading to detrimental long-term outcomes and often to adult pathologies through programming effects. Hormones, together with growth factors, play critical roles in the regulation of maternal-fetal and maternal-neonate interfaces, and alterations in any of them may lead to programming effects on the developing organism. In this chapter, we will review the role of sex steroids, thyroid hormones, and insulin-like growth factors, as crucial factors involved in physiological processes during pregnancy and lactation, and their role in developmental programming effects during fetal and early neonatal life. Also, we will consider epidemiological evidence and data from animal models of altered maternal hormonal environments and focus on the role of different tissues in the establishment of maternal and fetus/infant interaction. Finally, we will identify unresolved questions and discuss potential future research directions.

Effects of the Myokine Irisin on Stromal Cells from Swine Adipose Tissue

Irisin is a hormone able to reproduce some of the positive effects of physical activity and diet. Recently, we demonstrated the presence of Irisin at the ovarian level as a potential physiological regulator of follicular function. Adipose tissue is crucial for reproductive function through its metabolic activity and the production of adipokines. At present, the exact nature of adipocyte precursors is still under debate, but an important role has been assigned to the population of adipose tissue mesenchymal stromal cells (ASCs) of perivascular origin. It should be noted that, when appropriately stimulated, ASCs can differentiate into preadipocytes and, subsequently, adipocytes. Therefore, this present study was undertaken to explore the potential effect of Irisin on ASCs, known for their high differentiative potential. Since Irisin expression in ASCs was confirmed by PCR, we tested its potential effects on the main functional activities of these cells, including proliferation (BrdU uptake); metabolic activity (ATP production); redox status, evaluated as the generation of free molecules such as superoxide anion and nitric oxide; and scavenger activities, assessed as both enzymatic (superoxide dismutase) and non-enzymatic antioxidant power. Moreover, we tested the effect of Irisin on ASCs adipogenic differentiation. BrdU uptake was significantly (p < 0.001) inhibited by Irisin, while ATP production was significantly (p < 0.05) increased. Both superoxide anion and nitric oxide generation were significantly increased (p < 0.001) by Irisin, while scavenger activity was significantly reduced (p < 0.05). Irisin was found to significantly (p < 0.05) inhibit ASCs adipogenic differentiation. Taken together, the present results suggest a potential local role of Irisin in the regulation of adipose tissue function.

The Sexual Dimorphism of Human Adipose Depots

The amount and the distribution of body fat exhibit trajectories that are sex- and human species-specific and both are determinants for health. The enhanced accumulation of fat in the truncal part of the body as a risk factor for cardiovascular and metabolic diseases is well supported by epidemiological studies. In addition, a possible independent protective role of the gluteofemoral fat compartment and of the brown adipose tissue is emerging. The present narrative review summarizes the current knowledge on sexual dimorphism in fat depot amount and repartition and consequences on cardiometabolic and reproductive health. The drivers of the sex differences and fat depot repartition, considered to be the results of complex interactions between sex determination pathways determined by the sex chromosome composition, genetic variability, sex hormones and the environment, are discussed. Finally, the inter- and intra-depot heterogeneity in adipocytes and progenitors, emphasized recently by unbiased large-scale approaches, is highlighted.

Lipodystrophies in Children

BACKGROUND

Lipodystrophy includes a wide group of diseases characterized by reduction, absence, or altered distribution of adipose tissue. Lipodystrophies are classified into generalized or partial, according to the fat distribution, and congenital or acquired, considering the etiology.

SUMMARY

Impaired glucose and lipid metabolism are typically present, thus severe insulin resistance, diabetes mellitus, dyslipidemia, and hepatic steatosis are frequent complications. Because of the rarity and the diversification of lipodystrophies, diagnosis might be challenging, typically for partial forms that cannot be easily recognized, leading to progression of the several metabolic abnormalities associated. First management of lipodystrophy is diet and lifestyle changes, followed by the treatment of metabolic complications. Replacement therapy with metreleptin, currently available in the USA and Europe, has shown improvement of metabolic profile in a great number of patients with lipodystrophy.

KEY MESSAGES

The purpose of this review was to describe the phenotypic characteristics of all the known lipodystrophic types and to present specific steps for obtaining an early diagnosis and assessing the best treatment of lipodystrophy.

Asprosin promotes steroidogenesis and spermatogenesis with improved glucose metabolism in adult mice testis

Asprosin is an orexigenic adipokine that regulates appetite and glucose homeostasis in mammals. To date, only fragmentary findings are reported regarding its role in testicular activities. In the current investigation, immunolocalization and direct action of asprosin in adult mice testis was evaluated. Immunohistochemical and immunoblot studies were performed to analyse the testicular expression of asprosin. Intratesticular treatment of asprosin (0.1 μg and 1.0 μg per testis) was given to evaluate its direct action on testicular functions. Sertoli and Leydig cells were found to be immuno-positive for asprosin. Intratesticular administration of asprosin resulted into a significant increase in glucose and lactate levels along with enhanced expression of asprosin receptor OLFR734, insulin receptor (IR), glucose transporter 8 (GLUT 8), lactate dehydrogenase (LDH) activity and monocorboxylate transporters (MCT2 and 4). In addition, asprosin administration increased the testicular expression of cell proliferation (proliferating cell nuclear antigen: PCNA), cell survival (B cell lymphoma 2: Bcl2) and decreased germ cell apoptosis (Cysteine aspartic acid protease 3: Caspase 3) leading to increased sperm counts. Further, asprosin treatment resulted into increased level of total cholesterol, testosterone and steroidogenic markers (steroidogenic acute regulatory protein: StAR; 3beta-hydroxysteroid dehydrogenases: 3β HSD and 17beta-hydroxysteroid dehydrogenases: 17β HSD). Asprosin treatment promotes testicular glucose uptake and lactate synthesis to provide energy for steroidogenesis and spermatogenesis. The significant correlation between the asprosin-induced increased IR expression and increased testosterone, glucose and lactate levels suggests its role in increased survival and proliferation but decrease in germ cell apoptosis. This study proposed asprosin's role as an autocrine/paracrine regulator of testicular functions in adult mice.

Chemerin: A Functional Adipokine in Reproductive Health and Diseases

As a multifaceted adipokine, chemerin has been found to perform functions vital for immunity, adiposity, and metabolism through its three known receptors (chemokine-like receptor 1, CMKLR1; G-protein-coupled receptor 1, GPR1; C-C motif chemokine receptor-like 2, CCRL2). Chemerin and the cognate receptors are also expressed in the hypothalamus, pituitary gland, testis, ovary, and placenta. Accumulating studies suggest that chemerin participates in normal reproduction and underlies the pathological mechanisms of certain reproductive system diseases, including polycystic ovary syndrome (PCOS), preeclampsia, and breast cancer. Herein, we present a comprehensive review of the roles of the chemerin system in multiple reproductive processes and human reproductive diseases, with a brief discussion and perspectives on future clinical applications.

A 2022 update on the epidemiology of obesity and a call to action: as its twin COVID-19 pandemic appears to be receding, the obesity and dysmetabolism pandemic continues to rage on

The WHO just released in May 2022 a report on the state of the obesity pandemic in Europe, stating that 60% of citizens in the area of Europe are either overweight or obese, and highlighting the implications of the obesity pandemic, especially as it interacts with the COVID pandemic to create a twin pandemic, to increase morbidity and mortality. Obesity is a complex disease which has reached pandemic dimensions. The worldwide prevalence of obesity has nearly tripled since 1975, mainly due to the adoption of a progressively more sedentary lifestyle and the consumption of less healthy diets. We first report herein updated prevalence rates of overweight and obesity by sex, age, and region first in Europe, per the WHO report, and then worldwide between 1980 and 2019, as we analyze and present herein the data provided by the Global Burden of Disease Study. The prevalence of obesity is higher in women than in men of any age and the prevalence of both overweight and obesity increases with age and has reached their highest point between the ages of 50 to 65 years showing a slight downward trend afterwards. The age-standardized prevalence of obesity has increased from 4.6% in 1980 to 14.0% in 2019. The American and European region have the highest obesity prevalence and the USA and Russia are the countries with the most obese residents. Given dire implications in terms of comorbidities and mortality, these updated epidemiological findings call for coordinated actions from local and regional governments, the scientific community and individual patients alike, as well as the food industry for the obesity pandemic to be controlled and alleviated. We can hopefully learn from the COVID-19 pandemic, where collaborative efforts worldwide, focused intense work at both the local and global level and well-coordinated leadership have demonstrated that humankind is capable of amazing accomplishments by leveraging science and public health, and that we can finally make strides in terms of understanding and combating the obesity pandemic and its dire comorbidities including diabetes, NAFLD, CVD and obesity associated malignancies.

Adipose tissue and ovarian aging: Potential mechanism and protective strategies

Ovarian aging occurs approximately 10 years prior to the natural age-associated functional decline of other organ systems. With the increase of life expectancy worldwide, ovarian aging has gradually become a key health problem among women. Therefore, understanding the causes and molecular mechanisms of ovarian aging is very essential for the inhibition of age-related diseases and the promotion of health and longevity in women. Recently, studies have revealed an association between adipose tissue (AT) and ovarian aging. Alterations in the function and quantity of AT have profound consequences on ovarian function because AT is central for follicular development, lipid metabolism, and hormonal regulation. Moreover, the interplay between AT and the ovary is bidirectional, with ovary-derived signals directly affecting AT biology. In this review, we summarize the current knowledge of the complex molecular mechanisms controlling the crosstalk between the AT and ovarian aging, and further discuss how therapeutic targeting of the AT can delay ovarian aging.

Asprosin modulates testicular functions during ageing in mice

Ageing is a gradual and multi-factorial process with a significant impact on fertility. The mechanism of declined testicular functions with age remains elusive. Asprosin is a novel fasting-induced gluconeogenic adipokine that regulates glucose homeostasis. However, the expression and potential role of asprosin in testicular functions with age are largely unexplored. So, the current study was aimed to examine the variation in asprosin expression in the mice testis and its correlation with OLFR734 receptor, insulin receptor (IR), GLUT-8 and various steroidogenic markers at different stages of postnatal development. The result demonstrated the highest expression of asprosin in reproductively active mice, which decreased significantly in aged mice testis. Asprosin expression declined simultaneously with declining testosterone production, testicular glucose and expression of OLFR734, IR, GLUT-8 and AR in aged mice testis. This suggests that declining asprosin expression with advancing age may be a causative factor for regressive changes in the testis. Further, the present study also evaluated the in vitro effect of asprosin on testicular functions of aged mice testis. The results showed that asprosin treatment improves testicular functions by stimulating the expression of OLFR734, StAR, 3β-HSD,17β-HSD, IR, GLUT-8, MCT-2&4, PCNA, Bcl2 proteins alongwith increased testosterone, insulin and lactate biosynthesis. Collectively, these findings indicate that a marked decline in asprosin and its receptor OLFR734 expression may result in decreased insulin sensitivity and glucose transport, leading to regressive changes in aged mice testis. Treatment of asprosin can possibly restore the testicular functions of aged mice by augmenting the testosterone, insulin and glucose levels.

Associations of Obesity with Linear Growth and Puberty

BACKGROUND

The prevalence of obesity in childhood has increased dramatically in recent decades with increased risk of developing cardiometabolic and other comorbidities. Childhood adiposity may also influence processes of growth and puberty.

SUMMARY

Growth patterns of obesity during childhood have been shown to be associated with increased linear growth in early childhood, leading to accelerated epiphyseal growth plate (EGP) maturation. Several hormones secreted by the adipose tissue may affect linear growth in the context of obesity, both via the growth hormone IGF-1 axis and via a direct effect on the EGP. The observation that children with obesity tend to mature earlier than lean children has led to the assumption that the degree of body fatness may trigger the neuroendocrine events that lead to pubertal onset. The most probable link between obesity and puberty is leptin and its interaction with the kisspeptin system, which is an important regulator of puberty. However, peripheral action of adipose tissue could also be involved in changes in the onset of puberty. In addition, nutritional factors, epigenetics, and endocrine-disrupting chemicals are potential mediators linking pubertal onset to obesity. In this review, we focused on interactions of obesity with linear growth and pubertal processes, based on basic research and clinical data in humans.

KEY MESSAGE

Children with obesity are subject to accelerated linear growth with risk of impaired adult height and early puberty, with its psychological consequences. The data highlight another important objective in combatting childhood obesity, for the prevention of abnormal growth and pubertal patterns.

Resistin Modulates Low-Density Lipoprotein Cholesterol Uptake in Human Placental Explants via PCSK9

Maternal metabolic status influences pregnancy and, consequently, the perinatal outcome. Resistin is a pro-inflammatory adipokine predominantly expressed and secreted by mononuclear cells, adipose tissue, and placental trophoblastic cells during pregnancy. Recently, we reported an inverse association between maternal resistin levels and fetal low-density lipoprotein cholesterol (LDL-C). Then, in this work, we used a human placental explant model and the trophoblast cell line JEG-3 to evaluate whether resistin affects placental LDL-C uptake. Resistin exposure induced the transcription factor SREBP-2, LDLR, and PCSK9 mRNA expression, and changes at the protein level were confirmed by immunohistochemistry and Western blot. However, for LDLR, the changes were not consistent between mRNA and protein levels. Using a labeled LDL-cholesterol (BODIPY FL LDL), uptake assay demonstrated that the LDL-C was significantly decreased in placental explants exposed to a high dose of resistin and a lesser extent in JEG-3 cells. In summary, resistin induces PCSK9 expression in placental explants and JEG-3 cells, which could be related to negative regulation of the LDLR by lysosomal degradation. These findings suggest that resistin may significantly regulate the LDL-C uptake and transport from the maternal circulation to the fetus, affecting its growth and lipid profile.

Adiponectin promotes repair of renal tubular epithelial cells by regulating mitochondrial biogenesis and function

BACKGROUND

Mitochondrial biogenesis and dysfunction are associated with renal tubular epithelial cell injury and the pathophysiological development of diabetic nephropathy (DN). Adiponectin (APN) is a plasma hormone protein specifically secreted by adipocytes. In the present study, we studied the effects of APN on mitochondrial biogenesis and function in renal tubular epithelial cells and examined the mechanisms underlying its actions.

MATERIALS

A rat model of type 2 diabetes mellitus (T2DM) was established using streptozotocin (STZ), and an NRK-52E culture model exposed to high glucose was also used. We found that APN treatment alleviated kidney histopathological injury in T2DM rats, reduced fasting blood glucose (FBG) and postprandial blood glucose (PBG) levels, maintained stable animal weight, promoted cell viability, inhibited apoptosis and the formation of autophagosomes, and also increased mitochondrial mass, mitochondrial DNA (mtDNA) content and mitochondrial membrane potential (MMP) in vivo and in vitro.

RESULTS

We found that the expression of AdipoR1/CREB/PGC-1α/TFAM pathway proteins and respiratory chain complex subunits CO1, CO2, CO3, ATP6 and ATP8 were significantly increased after APN treatment. We also found that inhibition of cAMP response element binding protein (CREB) weakened the effects of APN in NRK-52E cells treated with high glucose. Coimmunoprecipitation experiments showed that AdipoR1 interacted with CREB.

CONCLUSION

APN promoted mitochondrial biogenesis and function in renal tubular epithelial cells by regulating the AdipoR1/CREB/PGC-1α/TFAM pathway. APN has the potential to serve as an effective drug for the treatment of DN.

Effect of Irisin on LIF and integrin αvβ3 in rats of implantation failure

OBJECTIVE

The aim of this study is to investigate the effect of irisin on leukemia inhibitory factor (LIF) and integrin αvβ3 in implantation failure uterus.

METHODS

Early pregnant rats were randomly divided into normal group (N), mifepristone treated group (M), irisin group (I) and progestin group (P). The implantation failure model was established using mifepristone. Second, we evaluated the average number of embryos and detected the expression of LIF and integrin αvβ3 protein and mRNA in endometrium.

RESULTS

Compared with group M, the average number of embryos was significantly higher in group N, P and I, the expression of LIF and integrin αvβ3 in endometrium was significantly higher in group N, P and I.

CONCLUSION

Irisin could improve the poor receptive state of endometrium by promoting LIF and integrin αvβ3 secretion to improve blastocyst implantation in rats of implantation failure.

Role of Kisspeptin in Regulation of Reproductive and Immune Reactions

The work is focused on physiological role of the hormone kisspeptin produced by neurons of the hypothalamus anterior zone, which is a key regulator of reproduction processes. Role of the hormone in transmission of information on metabolic activity and induction of the secretion of gonadotropin-releasing hormone (GnRH) by the hypothalamus that determines gestation processes involving fertilization, placentation, fetal development, and child birth is considered. The literature data on molecular mechanisms and effects of kisspeptin on reproductive system including puberty initiation are summarized and analyzed. In addition, attention is paid to hormone-mediated changes in the cardiovascular system in pregnant women. For the first time, the review examines the effect of kisspeptin on functional activity of immune system cells presenting molecular mechanisms of the hormone signal transduction on the level of lymphoid cells that lead to the immune tolerance induction. In conclusion, a conceptual model is presented that determines the role of kisspeptin as an integrator of reproductive and immune functions during pregnancy.

Contrasting association of Leptin receptor polymorphisms and haplotypes with polycystic ovary syndrome in Bahraini and Tunisian women: a case-control study

BACKGROUND

The present study examined the contribution of ethnicity to the association of leptin receptor gene (LEPR) gene variants with polycystic ovary syndrome (PCOS) in Tunisian and Bahraini Arabic-speaking women.

METHODS

Subjects consisted of 320 women with PCOS, and 446 eumenorrhic women from Tunisia, and 242 women with PCOS and 238 controls from Bahrain. Genotyping of (exonic) rs1137100 and rs1137101 and (intronic) rs2025804 LEPR variants was done by allelic exclusion.

RESULTS

The minor allele frequencies (MAFs) of rs1137100 and rs1137101 were significantly different between PCOS cases and control women from Bahrain but not Tunisia, and LEPR rs1137101 was associated with increased PCOS susceptibility only in Bahraini subjects. Furthermore, rs1137100 was associated with decreased PCOS risk among Bahrainis under codominant and recessive models; rs1137100 was negatively associated with PCOS in Tunisians after controlling for testosterone. In addition, rs2025804 was associated with increased PCOS risk among Tunisian but not Bahraini women, after adjusting for key covariates. Negative correlation was seen between rs1137101 and triglycerides in Tunisians, while homeostasis model assessment of insulin resistance (HOMA-IR) and insulin correlated with rs2025804 and rs1137101 among Bahraini subjects, and rs1137101 correlated with estradiol and prolactin. Taking TAG haplotype as common, positive association of TAA and negative association of TGG haplotype with PCOS was seen among Bahraini women; no three-locus PCOS-associated haplotypes were found in Tunisians.

CONCLUSIONS

The present study is the first to demonstrate the contribution of ethnicity to the association of LEPR gene variants with PCOS, thereby highlighting the significance of controlling for ethnicity in gene association investigations.

The follicular levels of adipokines and their ratio as the prognostic markers of in vitro fertilization outcomes

INTRODUCTION

Adipokines are involved in the regulation of the female reproductive system. The purpose was to study the possibility of using adipokines levels in the follicular fluid to predict IVF efficiency.

MATERIALS AND METHODS

Four groups of women were studied: pregnant during IVF, with normal (PN, n = 9) and increased (BMI > 25 kg/m²) body weight (BW) (PI, n = 7), and nonpregnant during IVF, with normal (nPN, n = 16) and increased BW (nPI, n = 21).

RESULTS

In PN group, leptin level was higher than in nPN group (p < .05). In the PI and nPI groups, it did not differ, but was higher than in women with normal BW. In PN group, ghrelin level was lower than in nPN group (p < .05), while in the PI and nPI groups it was comparable. The leptin/ghrelin ratio in PN group was higher than in nPN group (18.10 ± 3.38 vs. 3.93 ± 0.60, p < .05), but lower than in the PI (31.70 ± 15.38) and nPI (24.30 ± 3.45) groups. The leptin/adiponectin ratio in PN group was also higher than in nPN group (6.97 ± 0.64 vs. 2.95 ± 0.39, p < .05), but lower than in the PI (13.60 ± 1.59) and nPI (10.86 ± 0.87) groups. Adiponectin levels differed only between the nPN and nPI groups. In women with normal BW, odds ratio showed that the leptin/ghrelin ratio has the greatest prognostic value for predicting the success of IVF outcomes (OR: 29.53; CI: 1.53-570.83, p =.025) among other indicators. In women with increased BW, none of the indicators had predictive value.

CONCLUSION

The follicular leptin/ghrelin ratio is a suitable indicator for predicting IVF outcomes in women with normal BW.

Is there a hypothalamic basis for anorexia nervosa?

The hypothalamus has long been known to control food intake and energy metabolism through a complex network of primary and secondary neurons and glial cells. Anorexia nervosa being a complex disorder characterized by abnormal feeding behavior and food aversion, it is thus quite surprising that not much is known concerning potential hypothalamic modifications in this disorder. In this chapter, we review the recent advances in the fields of genetics, epigenetics, structural and functional imaging, and brain connectivity, as well as neuroendocrine findings and emerging animal models, which have begun to unravel the importance of hypothalamic adaptive processes to our understanding of the pathology of eating disorders.

Research Progress on the Effect of Epilepsy and Antiseizure Medications on PCOS Through HPO Axis

Epilepsy is a common chronic neurological disease that manifests as recurrent seizures. The incidence and prevalence of epilepsy in women are slightly lower than those in men. Polycystic ovary syndrome (PCOS), a reproductive endocrine system disease, is a complication that women with epilepsy are susceptible to, and its total prevalence is 8%-13% in the female population and sometimes as high as 26% in female epilepsy patients. The rate of PCOS increased markedly in female patients who chose valproate (VPA), to 1.95 times higher than that of other drugs. In addition, patients receiving other anti-seizure medications (ASMs), such as lamotrigine (LTG), oxcarbazepine (OXC), and carbamazepine (CBZ), also have reproductive endocrine abnormalities. Some scholars believe that the increase in incidence is related not only to epilepsy itself but also to ASMs. Epileptiform discharges can affect the activity of the pulse generator and then interfere with the reproductive endocrine system by breaking the balance of the hypothalamic-pituitary-ovarian (HPO) axis. ASMs may also cause PCOS-like disorders of the reproductive endocrine system through the HPO axis. Moreover, other factors such as hormone metabolism and related signalling pathways also play a role in it.

Pubertal mammary gland development is a key determinant of adult mammographic density

Mammographic density refers to the radiological appearance of fibroglandular and adipose tissue on a mammogram of the breast. Women with relatively high mammographic density for their age and body mass index are at significantly higher risk for breast cancer. The association between mammographic density and breast cancer risk is well-established, however the molecular and cellular events that lead to the development of high mammographic density are yet to be elucidated. Puberty is a critical time for breast development, where endocrine and paracrine signalling drive development of the mammary gland epithelium, stroma, and adipose tissue. As the relative abundance of these cell types determines the radiological appearance of the adult breast, puberty should be considered as a key developmental stage in the establishment of mammographic density. Epidemiological studies have pointed to the significance of pubertal adipose tissue deposition, as well as timing of menarche and thelarche, on adult mammographic density and breast cancer risk. Activation of hypothalamic-pituitary axes during puberty combined with genetic and epigenetic molecular determinants, together with stromal fibroblasts, extracellular matrix, and immune signalling factors in the mammary gland, act in concert to drive breast development and the relative abundance of different cell types in the adult breast. Here, we discuss the key cellular and molecular mechanisms through which pubertal mammary gland development may affect adult mammographic density and cancer risk.

Combined effects of obesity and di-(2-ethylhexyl) phthalate on testosterone levels and kisspeptin/GPR54 expression in hypothalamus and testes of male mice

BACKGROUND

This study evaluated whether obese male mice exposed to di-(2-ethylhexyl) phthalate (DEHP) showed synergistic effects on testosterone levels and the potential underlying mechanism.

METHODS

Forty-eight male mice were assigned to six groups for 12-week treatments as follows: normal, DEHP100, diet-induced obesity (DIO), DIO + DEHP30, DIO + DEHP100, and DIO + DEHP300. Serum hormone levels, including testosterone (T), luteinizing hormone (LH), and leptin, were detected by ELISA. The levels of Ob-R, kisspeptin, and GPR54 protein expression in hypothalamus and testicular tissues were measured by western blot.

RESULTS

There were significantly lower levels of serum T and LH, higher levels of serum leptin and Ob-R, and kisspeptin and GPR54 protein expression were reduced in hypothalamus and testicular tissues in the DIO and DEHP groups compared with controls. Moreover, serum T and leptin levels were more severe in the combined DIO and DEHP exposure group than in the single exposure groups. Serum LH levels and GPR54 expression in the testis were significantly decreased in DIO + DEHP300 mice compared with DIO mice (p < 0.05).

CONCLUSION

Obesity- and DEHP-only exposure had adverse effects on testosterone levels in mice, which may be due to high leptin levels and decreased Ob-R, kisspeptin, and GPR54 expression. Obesity combined with DEHP exposure had an additive adverse effect on testosterone levels in mice. One of the potential mechanisms is higher leptin levels and decreased GPR54 expression in the testes.

[The immune system of adipose tissue: obesity-associated inflammation]

Adipose tissue is an important endocrine organ. Via its secretion products, it cross-talks with other organs of the body and communicates the filling state of its triglyceride stores. Obesity is characterized by the excessive accumulation of body fat and leads to the infiltration and accumulation of immune cells in white adipose tissue. In this review article we introduce the various immune cell populations of adipose tissue and discuss their local and systemic influence.

Metabolic regulation of kisspeptin - the link between energy balance and reproduction

Hypothalamic kisspeptin neurons serve as the nodal regulatory centre of reproductive function. These neurons are subjected to a plethora of regulatory factors that ultimately affect the release of kisspeptin, which modulates gonadotropin-releasing hormone (GnRH) release from GnRH neurons to control the reproductive axis. The presence of sufficient energy reserves is critical to achieve successful reproduction. Consequently, metabolic factors impose a very tight control over kisspeptin synthesis and release. This Review offers a synoptic overview of the different steps in which kisspeptin neurons are subjected to metabolic regulation, from early developmental stages to adulthood. We cover an ample array of known mechanisms that underlie the metabolic regulation of KISS1 expression and kisspeptin release. Furthermore, the novel role of kisspeptin neurons as active players within the neuronal circuits that govern energy balance is discussed, offering evidence of a bidirectional role of these neurons as a nexus between metabolism and reproduction.

The effect of excess body fat on female and male reproduction

The dramatic increase in the prevalence of obesity coincides with a decline in reproductive health indices in both sexes. Energy excess mediates changes to the regulatory mechanisms of the reproductive system. Obese individuals exhibit increased estrogen concentrations, due to the overexpression of aromatase in the adipose tissue; via a negative feedback loop, men present with symptoms of hypogonadotropic hypogonadism. These hormonal changes, along with increased oxidative stress, lipotoxicity and disturbances in the concentrations of adipokines, directly affect the gonads, peripheral reproductive organs and the embryo. Clinical evidence is somewhat contradicting, with only some studies advocating worse semen parameters, increased incidence of erectile dysfunction, increased doses of ovulation induction medications, and worse live birth rates in assisted reproductive technology (ART) cycles in obese individuals compared with those of normal weight. Similar conclusions are drawn about patients with insulin resistance syndromes, namely polycystic ovary syndrome (PCOS). As far as treatment options are concerned, lifestyle changes, medical therapy and bariatric surgery may improve the reproductive outcome, although the evidence remains inconclusive. In this review, we summarize the evidence on the association of obesity and reproductive health on both the molecular and the clinical level, and the effect of weight-loss interventions on reproductive potential.

Adipokines: A gear shift in puberty

In this review, we discuss the role of adipokines in the onset of puberty in children with obesity during adrenarche and gonadarche and provide a clear and detailed overview of the biological processes of two major players, leptin and adiponectin. Adipokines, especially leptin and adiponectin, seem to induce an early onset of puberty in girls and boys with obesity by affecting the hypothalamic-pituitary-gonadal (HPG) axis. Moreover, adipokines and their receptors are expressed in the gonads, suggesting a role in sexual maturation and reproduction. All in all, adipokines may be a clue in understanding mechanisms underlying the onset of puberty in childhood obesity and puberty onset variability.

The effect of underweight on female and male reproduction

Chronic energy deficiency can impair the hypothalamic-pituitary-gonadal (HPG) axis and lead to hypothalamic anovulation in underweight women. This review presents the syndromes related to underweight status that are associated with infertility, summarizes the underlying mechanisms, and reviews the available treatment options. Eating disorders, such as anorexia nervosa (AN), constitute the most common cause of infertility in underweight women, who, in addition, experience miscarriages, and sexual dysfunction. The relative energy deficiency in sports (RED-S; former terminology: athlete's triad) involves menstrual dysfunction due to low energy availability, which results in anovulation. Moreover, lipodystrophies, malnutrition, starvation, systematic illnesses (malignancies, endocrinopathies, infectious diseases, advanced chronic diseases, neurologic illnesses), and the utilization of drugs can cause excessive weight loss. They may result in fertility problems due to the loss of adipose tissue and the subsequent hormonal disturbances. Each of these conditions requires multidisciplinary management. Nutritional counseling should target the restoration of energy balance by increasing intake and reducing output. Medical treatment, recommended only for patients who did not respond to standard treatment, may include antipsychotics, antidepressants, or leptin administration. Finally, psychiatric treatment is considered an integral part of the standard treatment.

The role of serum adipokine levels in preeclampsia: A systematic review

BACKGROUND

Preeclampsia represents a major pregnancy complication, associated with high rates of perinatal morbidity. The aim of this systematic review is to accumulate current literature evidence in order to examine the pattern of serum adipokine levels among preeclamptic women and asses their potential efficacy in the prediction of the disease.

METHODS

Medline, Scopus, CENTRAL, Clinicaltrials.gov and Google Scholar databases were systematically searched from inception. All observational studies reporting serum adipokine values among preeclamptic and healthy pregnant women were held eligible.

RESULTS

A total of 163 studies were included, comprising 23,482 women. Leptin was evaluated in 91 studies and its values were found to be significantly elevated in preeclamptic women during all pregnancy trimester, independently of disease onset and severity. Preeclampsia was also associated with increased serum fatty acid binding protein-4 and chemerin levels, when measured both during the 1st and 3rd trimester. Data concerning the rest adipokines were either conflicting or limited to reach firm conclusions. Quality of evidence was evaluated to be high for leptin, moderate for serum fatty acid binding protein-4 and chemerin and low for the other adipokines.

CONCLUSIONS

The existing evidence suggests that preeclampsia is linked to increased levels of leptin, chemerin and fatty acid binding protein-4 in all pregnancy trimesters and forms of the disease. Inconsistent data currently exists concerning the role of the other adipokines. Large-scale prospective studies should longitudinally evaluate the serum concentration of novel adipokines and define the optimal threshold and timing of measurement to be widely applied in clinical practice.

Familial Partial Lipodystrophy (FPLD): Recent Insights

Lipodystrophies are a heterogeneous group of congenital or acquired disorders, characterized by partial or generalized loss of adipose tissue. Familial partial lipodystrophy (FPLD) presents with genetic and phenotypic variability with insulin resistance, hypertriglyceridemia and hepatic steatosis being the cardinal metabolic features. The severity of the metabolic derangements is in proportion with the degree of lipoatrophy. The underpinning pathogenetic mechanism is the limited capacity of adipose tissue to store lipids leading to lipotoxicity, low-grade inflammation, altered adipokine secretion and ectopic fat tissue accumulation. Advances in molecular genetics have led to the discovery of new genes and improved our knowledge of the regulation of adipose tissue biology. Diagnosis relies predominantly on clinical findings, such as abnormal fat tissue topography and signs of insulin resistance and is confirmed by genetic analysis. In addition to anthropometry and conventional imaging, new techniques such as color-coded imaging of fat depots allow more accurate assessment of the regional fat distribution and differentiation of lipodystrophic syndromes from common metabolic syndrome phenotype. The treatment of patients with lipodystrophy has proven to be challenging. The use of a human leptin analogue, metreleptin, has recently been approved in the management of FPLD with evidence suggesting improved metabolic profile, satiety, reproductive function and self-perception. Preliminary data on the use of glucagon-like peptide 1 receptor agonists (GLP1 Ras) and sodium-glucose co-transporter 2 (SGLT2) inhibitors in cases of FPLD have shown promising results with reduction in total insulin requirements and improvement in glycemic control. Finally, investigational trials for new therapeutic agents in the management of FPLD are underway.

Potential physiological involvement of nesfatin-1 in regulating swine granulosa cell functions

Nesfatin-1 has recently been indicated as a pleiotropic molecule that is primarily involved in the metabolic regulation of reproductive functions acting at hypothalamic level. The aim of this study was to explore the local action of nesfatin-1 in swine ovarian follicles. Nucleobindin 2 (NUCB2) was verified using real-time quantitative polymerase chain reaction in swine granulosa cells from different sized follicles and nesfatin-1 was localised by immunohistochemistry in sections of the whole porcine ovary. The effects of different concentrations of nesfatin-1 on cell growth, steroidogenesis and the redox status of granulosa cells were determined invitro. In addition, the effects of nesfatin-1 were evaluated in an angiogenesis bioassay because vessel growth is essential for ovarian follicle function. Immunohistochemistry revealed intense positivity for nesfatin-1 in swine granulosa cells in follicles at all developmental stages. Expression of the gene encoding the precursor protein NUCB2 was higher in granulosa cells from large rather than from medium and small follicles. Further, nesfatin-1 stimulated cell proliferation and progesterone production and interfered with redox status by modifying nitric oxide production and non-enzyme scavenging activity in granulosa cells from large follicles. Moreover, nesfatin-1 exhibited a stimulatory effect on angiogenesis. This study demonstrates, for the first time, that nesfatin-1 is physiologically present in the swine ovarian follicle, where it may impair granulosa cell functions.

A Metabolic Perspective on Reward Abnormalities in Anorexia Nervosa

Anorexia nervosa (AN) is the psychiatric disorder with the highest mortality rate; however, the mechanisms responsible for its pathogenesis remain largely unknown. Large-scale genome-wide association studies (GWAS) have identified genetic loci associated with metabolic features in AN. Metabolic alterations that occur in AN have been mostly considered as consequences of the chronic undernutrition state but until recently have not been linked to the etiology of the disorder. We review the molecular basis of AN based on human genetics, with an emphasis on the molecular components controlling energy homeostasis, highlight the main metabolic and endocrine alterations occurring in AN, and decipher the possible connection between metabolic factors and abnormalities of reward processes that are central in AN.

In vitro tissue-engineered adipose constructs for modeling disease

BACKGROUND

Adipose tissue is a vital tissue in mammals that functions to insulate our bodies, regulate our internal thermostat, protect our organs, store energy (and burn energy, in the case of beige and brown fat), and provide endocrine signals to other organs in the body. Tissue engineering of adipose and other soft tissues may prove essential for people who have lost this tissue from trauma or disease.

MAIN TEXT

In this review, we discuss the applications of tissue-engineered adipose tissue specifically for disease modeling applications. We provide a basic background to adipose depots and describe three-dimensional (3D) in vitro adipose models for obesity, diabetes, and cancer research applications.

CONCLUSIONS

The approaches to engineering 3D adipose models are diverse in terms of scaffold type (hydrogel-based, silk-based and scaffold-free), species of origin (H. sapiens and M. musculus) and cell types used, which allows researchers to choose a model that best fits their application, whether it is optimization of adipocyte differentiation or studying the interaction of adipocytes and other cell types like endothelial cells. In vitro 3D adipose tissue models support discoveries into the mechanisms of adipose-related diseases and thus support the development of novel anti-cancer or anti-obesity/diabetes therapies.

Developmental onset of cardiovascular disease-Could the proof be in the placenta?

The Barker Hypothesis states change to the maternal environment may have significant impacts on fetal development, setting the stage for adult disease to occur. The development of the maternofetal vasculature during implantation and maintenance during pregnancy is extremely precise, yet dynamic. Delays or dysfunction in the orchestration of anatomical remodeling, maintenance of blood pressure, or responsiveness to metabolic demand may have severe consequences to the developing fetus. While these intermissions may not be fatal to the developing fetus, an interruption, reduction, or an inability to meet fetal demand of blood flow during crucial stages of development may predispose young to disease later in life. Maternal inability to meet fetal demand can be attributed to improper placental development and vascular support through morphological change or physiological function will significantly limit nutrient delivery and waste exchange to the developing fetus. Therefore, we present an overview of the uteroplacental vascular network, maternal cardiovascular adaptations that occur during pregnancy, placental blood flow, and common maternal comorbidities and/or exposures that may perturb maternal homeostasis and affect fetal development. Overall, we examine uterine microvasculature pathophysiology contributing to a hostile gestational environment and fetal predisposition to disease as it relates to the Barker Hypothesis.

Breast Cancer: Proteolysis and Migration

Understanding breast cancer cell proteolysis and migration is crucial for developing novel therapies to prevent local and distant metastases. Human cancer cells utilize many biological functions comparable to those observed during embryogenesis conferring the cancer cells with survival advantages. One such advantage is the ability to secrete proteases into the tumor microenvironment in order to remodel the extracellular matrix to facilitate migration. These proteases degrade the extracellular matrix, which initially functions as a barrier to cancer cell escape from their site of origin. The extracellular matrix also functions as a reservoir for growth factors that can be released by the secreted proteases and thereby further aid tumor growth and progression. Other survival advantages of tumor cells include: the ability to utilize multiple modes of motility, thrive in acidic microenvironments, and the tumor cell's ability to hijack stromal and immune cells to foster their own migration and survival. In order to reduce metastasis, we must focus our efforts on addressing the survival advantages that tumor cells have acquired.

Resveratrol Delivery from Porous Poly(lactide- co-glycolide) Scaffolds Promotes an Anti-Inflammatory Environment within Visceral Adipose Tissue

As biomaterial therapies emerge to address adipose tissue dysfunction that underlies metabolic disease, the immune response to these systems must be established. As a potential therapy, we are investigating resveratrol delivery from porous poly(lactide- co-glycolide) scaffolds designed to integrate with adipose tissue. Resveratrol was selected for its ability to protect mice and primates from high fat diet and broad anti-inflammatory properties. Herein, we report fabrication of scaffolds with high resveratrol loading that are stable and active for up to one year. In vitro release profiles indicate that drug release is biphasic with a burst release over 3 days followed by a plateau. Surprisingly, we find that PLG scaffolds implanted into adipose tissue of mice promote an anti-inflammatory environment characterized by high arginase-1 and low TNF-α and IL-6 compared to naïve unmanipulated fat. Resveratrol delivery from the scaffold augments this anti-inflammatory environment by decreasing monocyte and lymphocyte numbers at the implant site and increasing expression of IL-10 and IL-13, cytokines that promote healthy adipose tissue. In terms of therapeutic applications, implant of scaffolds designed to release resveratrol into the visceral fat decreases MCP-1 expression in mice fed a high fat diet, a molecule that drives both local and systemic inflammation during obesity. Taken together, resveratrol delivery to adipose tissue using poly(lactide- co-glycolide) scaffolds is a promising therapeutic strategy for the treatment of adipose tissue inflammation that drives metabolic disease.

Is there a causal relationship between obesity and puberty?

The onset of puberty in adolescents and whether it is related to obesity is an ongoing topic for debate. Epidemiological cross-sectional and longitudinal studies show a shift towards earlier onset of puberty in girls who are obese; however, the situation is less clear in boys. Boys who are overweight seem to mature earlier, and boys who are obese mature later, than boys at a healthy weight. The underlying mechanisms are not yet fully understood, and whether earlier onset of puberty in obese girls is based on the activation of the hypothalamic-pituitary-gonadal axis is unclear. The most promising link between obesity and puberty is the adipokine leptin and its interaction with the kisspeptin system, which is an important regulator of puberty. However, peripheral action of adipose tissue (eg, via other adipokines, aromatase activity) could also be involved in changes to the onset of puberty. In addition, nutritional factors, epigenetics, or endocrine disrupting chemicals are potential mediators linking the onset of puberty to obesity. This Review summarises our knowledge concerning the relationship between obesity and onset and tempo of puberty, and the consequences of early puberty on obesity.

Downregulation of leptin receptor and kisspeptin/GPR54 in the murine hypothalamus contributes to male hypogonadism caused by high-fat diet-induced obesity

PURPOSE

Obesity may lead to male hypogonadism, the underlying mechanism of which remains unclear. In the present study, we established a murine model of male hypogonadism caused by high-fat diet-induced obesity to verify the following hypotheses: 1) an increased leptin level may be related to decreased secretion of GnRH in obese males, and 2) repression of kisspeptin/GPR54 in the hypothalamus, which is associated with increased leptin levels, may account for the decreased secretion of GnRH and be involved in secondary hypogonadism (SH) in obese males.

METHODS

Male mice were fed high-fat diet for 19 weeks and divided by body weight gain into diet-induced obesity (DIO) and diet-induced obesity resistant (DIO-R) group. The effect of obesity on the reproductive organs in male mice was observed by measuring sperm count and spermatozoid motility, relative to testis and epididymis weight, testosterone levels, and pathologic changes. Leptin, testosterone, estrogen, and LH in serum were detected by ELISA method. Leptin receptor (Ob-R), Kiss1, GPR54, and GnRH mRNA were measured by real-time PCR in the hypothalamus. Expression of kisspeptin and Ob-R protein was determined by Western blotting. Expression of GnRH and GPR54 protein was determined by immunohistochemical analysis.

RESULTS

We found that diet-induced obesity decreased spermatozoid motility, testis and epididymis relative coefficients, and plasma testosterone and luteinizing hormone levels. An increased number and volume of lipid droplets in Leydig cells were observed in the DIO group compared to the control group. Significantly, higher serum leptin levels were found in the DIO and DIO-R groups. The DIO and DIO-R groups showed significant downregulation of the GnRH, Kiss1, GPR54, and Ob-R genes. We also found decreased levels of GnRH, kisspeptin, GPR54, and Ob-R protein in the DIO and DIO-R groups.

CONCLUSIONS

These lines of evidence suggest that downregulation of Ob-R and kisspeptin/GPR54 in the murine hypothalamus may contribute to male hypogonadism caused by high-fat diet-induced obesity.

The expression and distribution of a leptin receptor in the central nervous system, digestive organs, and gonads of the giant freshwater prawn, Macrobrachium rosenbergii

In the present study, the presence and distribution of leptin receptor (LEP-R) in central nervous system, digestive organs, gonads of giant freshwater prawn, Macrobrachium rosenbergii, were investigated with Western blot and immunohistochemistry. By Western blot a LEP-R with a molecular weight (MW) of 100 kDa was detected in the brain, thoracic ganglia, abdominal ganglia, hepatopancreas, all parts of the gastrointestinal tract, ovaries, and testes. In hepatopancreas and foregut, another intense positive band was detected at molecular weight of 30 kDa, which could be an isotype of LEP-R. By immunohistochemistry, LEP-R-ir was detected in the neurons, and neuropils in the brain, thoracic ganglia, and abdominal ganglia. In the gastrointestinal tract, there was intense LEP-R-ir in the apical part of the epithelial cells of the foregut, midgut, and hindgut. In addition, LEP-R-ir was found in the Restzellen(R)cells and Fibrillenzellen(F) cells in the hepatopancreas. In the ovary, LEP-R-ir was detected in early stage of oocytes and mature oocytes. Intense LEP-R-ir was observed in spermatogonia and spermatocytes of the small and orange claw male prawns. In addition, LEP-R was seen in the high epithelium of spermatic ducts from all male morphotypes. In summary, the detection of the LEP-R-ir suggests the existence of a LEP-R in several organs of M. rosenbergii. Through binding with leptin peptide, LEP-R may be an important signaling molecule that has critical functions in modulating and controlling food intake, energy expenditure, and reproduction in this prawn.