Direct effects of sex steroid hormones on adipose tissues and obesity

The Mechanisms Involved in Obesity-Induced Male Infertility

BACKGROUND

Obesity resulted by imbalance between the intake of energy and energy consumption can lead to growth and metabolic disease development in people. Both in obese men and animal models, several studies indicate that obesity leads to male infertility.

OBJECTIVE

This review has discussed some mechanisms involved in obesity-induced male infertility.

METHODS

Online documents were searched through Science Direct, Pubmed, Scopus, and Google Scholar websites dating from 1959 to recognize studies on obesity, kisspeptin, leptin, and infertility.

RESULTS

Obesity induced elevated inflammatory cytokines and oxidative stress can affect male reproductive functions, including spermatogenesis disorders, reduced male fertility power and hormones involved in the hypothalamus-pituitary-gonadal axis.

CONCLUSION

There is significant evidence that obesity resulted in male infertility. Obesity has a negative effect on male reproductive function via several mechanisms such as inflammation and oxidative stress.

Loss of CTRP4 alters adiposity and food intake behaviors in obese mice

Central and peripheral mechanisms are both required for proper control of energy homeostasis. Among circulating plasma proteins, C1q/TNF-related proteins (CTRPs) have recently emerged as important regulators of sugar and fat metabolism. CTRP4, expressed in brain and adipose tissue, is unique among the family members in having two tandem globular C1q domains. We previously showed that central administration of recombinant CTRP4 suppresses food intake, suggesting a central nervous system role in regulating ingestive physiology. Whether this effect is pharmacological or physiological remains unclear. We used a loss-of-function knockout (KO) mouse model to clarify the physiological role of CTRP4. Under basal conditions, CTRP4 deficiency increased serum cholesterol levels and impaired glucose tolerance in male but not female mice fed a control low-fat diet. When challenged with a high-fat diet, male and female KO mice responded differently to weight gain and had different food intake patterns. On an obesogenic diet, male KO mice had similar weight gain as wild-type littermates. When fed ad libitum, KO male mice had greater meal number, shorter intermeal interval, and reduced satiety ratio. Female KO mice, in contrast, had lower body weight and adiposity. In the refeeding period following food deprivation, female KO mice had significantly higher food intake due to longer meal duration and reduced satiety ratio. Collectively, our data provide genetic evidence for a sex-dependent physiological role of CTRP4 in modulating food intake patterns and systemic energy metabolism.

The Effects of Complex Decongestive Physiotherapy Applications on Lower Extremity Circumference and Volume in Patients with Lipedema

Background: The aim of this study is to investigate the effect of complex decongestive physiotherapy (CDP) plus intermittent pneumatic compression (IPC) applications on lower extremity limb circumference and volume in patients with lipedema. Methods and Results: In measurement of limb volume and circumference measurement, the Perometer 400 NT was used before and after treatment. The perometer measurements in this study were performed in the certain five reference points (cB, cC, cD, cE, and CF). All participants included in the study were included in a treatment protocol consisting of CDP and IPC. It was seen that statistically significant reduction was found in the circumference of 3 of the 5 points of measurements performed in the left limb, whereas statistically significant reduction was found in the circumference of 4 of the 5 points of measurements performed in the right limb. When the assessments of limb volume performed with the perometer were compared before and after CDP, it was seen that statistically significant reduction was found in the volume of both limbs. Conclusion: This reduction indicates that CDP is effective in the treatment of lower extremity lipedema. Clinicaltrials.gov with an ID of NCT04492046.

Associations between serum total, free and bioavailable testosterone and non-alcoholic fatty liver disease in community-dwelling middle-aged and elderly women

BACKGROUND AND AIMS

Non-alcoholic fatty liver disease (NAFLD) is considered both a cause and consequence of the metabolic syndrome (MetS). While emerging evidence has indicated that testosterone is associated with MetS, the relationship between testosterone and NAFLD in women remains unclear. Therefore, this study investigated the associations between serum testosterone levels and NAFLD prevalence risk in a community-based cross-sectional study.

METHODS

A total of 2117 adult women were included in the analysis. Serum total testosterone (TT) was measured by chemiluminescence immunoassay, and other testosterone-related indices, such as concentrations and percentages of calculated free testosterone (cFT) and bioavailable testosterone (BioT), and free androgen index (FAI), were also calculated. NAFLD was diagnosed by clinical criteria. Logistic regression was used to explore these associations.

RESULTS

There were significant differences in TT, FAI, cFT and BioT between women with and without NAFLD (all P<0.001). Multivariate logistic-regression analyses demonstrated that both absolute concentrations and percentages of cFT and BioT were positively associated with NAFLD risk prevalence in all models. Adjusted ORs (95% CI) for quartile 4 vs quartile 1 of % cFT and % BioT were 5.94 (4.29-8.22) and 5.21 (3.79-7.17) in model 2, and 4.35 (3.07-6.18) and 3.58 (2.55-5.03) in model 3 (all P<0.001 for trend). In addition, quartiles of TT, FAI, cFT and BioT were significantly correlated with degree of hepatic steatosis. ROC analysis also showed that % cFT and % BioT were more accurate for predicting NAFLD prevalence than was TT.

CONCLUSION

Serum cFT and BioT were positively associated with NAFLD risk, and elevated levels of cFT and BioT could be independent risk factors of NAFLD prevalence in middle-aged and elderly women.

Vocal Indicators of Size, Shape and Body Composition in Polish Men

OBJECTIVES

From a human evolution perspective, identifying a link between physique and vocal quality could demonstrate dual signaling in terms of the health and biological condition of an individual. In this regard, this study investigates the relationship between men's body size, shape, and composition, and their vocal characteristics.

MATERIALS AND METHODS

Eleven anthropometric measurements, using seven indices, were carried out with 80 adult Polish male participants, while the speech analysis adopted a voice recording procedure that involved phonetically recording vowels /ɑː/, /ɛː/, /iː/, /ɔː/, /uː/ to define the voice acoustic components used in Praat software.

RESULTS

The relationship between voice parameters and body size/shape/composition was found. The analysis indicated that the formants and their derivatives were useful parameters for prediction of height, weight, neck, shoulder, waist, and hip circumferences. Fundamental frequency (F₀) was negatively correlated with neck circumference at Adam's apple level and body height. Moreover neck circumference and F₀ association was observed for the first time in this paper. The association between waist circumference and formant component showed a net effect. In addition, the formant parameters showed significant correlations with body shape, indicating a lower vocal timbre in men with a larger relative waist circumference.

DISCUSSION

Men with lower vocal pitch had wider necks, probably a result of larynx size. Furthermore, a greater waist circumference, presumably resulting from abdominal fat distribution in men, correlated with a lower vocal timbre. While these results are inconclusive, they highlight new directions for further research.

Acetylator Genotype-Dependent Dyslipidemia in Rats Congenic for N-Acetyltransferase 2

Recent reports suggest that arylamine N-acetyltransferases (NAT1 and/or NAT2) serve important roles in regulation of energy utility and insulin sensitivity. We investigated the interaction between diet (control vs. high-fat diet) and acetylator phenotype (rapid vs. slow) using previously established congenic rat lines (in F344 background) that exhibit rapid or slow Nat2 (orthologous to human NAT1) acetylator genotypes. Male and female rats of each genotype were fed control or high-fat (Western-style) diet for 26 weeks. We then examined diet- and acetylator genotype-dependent changes in body and liver weights, systemic glucose tolerance, insulin sensitivity, and plasma lipid profile. Male and female rats on the high fat diet weighed approximately 10% more than rats on the control diet and the percentage liver to body weight was consistently higher in rapid than slow acetylator rats. Rapid acetylator rats were more prone to develop dyslipidemia overall (i.e., higher triglyceride; higher LDL; and lower HDL), compared to slow acetylator rats. Total cholesterol (TC)-to-HDL ratios were significantly higher and HDL-to-LDL ratios were significantly lower in rapid acetylator rats. Our data suggest that rats with rapid systemic Nat2 (NAT1 in humans) genotype exhibited higher dyslipidemia conferring risk for metabolic syndrome and cardiovascular dysfunction.

The effect of lipedema on health-related quality of life and psychological status: a narrative review of the literature

PURPOSE

The aim of this narrative review of the literature was to evaluate and summarize the current literature regarding the effect of lipedema on health-related quality of life (HRQOL) and psychological status.

METHODS

The authors collected articles through a search into Medline, Embase, Scopus, Web of Science, Physiotherapy Evidence Database (PEDro), and the Cochrane Review. Search terms used included "Lipoedema," "Lipedema," "psychological status," "Quality of life," "Health related quality of life," and "HRQOL."

RESULTS

A total of four observational studies were evaluated. The included studies were moderate-quality according to the Newcastle-Ottawa Scale. Three of the included studies demonstrated deterioration of HRQOL and psychological status in patients with lipedema. These studies also identify that pain and tenderness are a more common and dominant characteristic.

CONCLUSION

Future studies should establish a specific approach to treat and manage lipedema symptoms. Based on this narrative review of the literature findings, we recommended for the health care provider to pay more attention to HRQOL and psychological status. Moreover, validated and adapted measures of HRQOL and psychological status for patients with lipedema are required.

LEVEL OF EVIDENCE

Level V, narrative review.

CTRP12 ablation differentially affects energy expenditure, body weight, and insulin sensitivity in male and female mice

Secreted hormones facilitate tissue cross talk to maintain energy balance. We previously described C1q/TNF-related protein 12 (CTRP12) as a novel metabolic hormone. Gain-of-function and partial-deficiency mouse models have highlighted important roles for this fat-derived adipokine in modulating systemic metabolism. Whether CTRP12 is essential and required for metabolic homeostasis is unknown. We show here that homozygous deletion of Ctrp12 gene results in sexually dimorphic phenotypes. Under basal conditions, complete loss of CTRP12 had little impact on male mice, whereas it decreased body weight (driven by reduced lean mass and liver weight) and improved insulin sensitivity in female mice. When challenged with a high-fat diet, Ctrp12 knockout (KO) male mice had decreased energy expenditure, increased weight gain and adiposity, elevated serum TNFα level, and reduced insulin sensitivity. In contrast, female KO mice had reduced weight gain and liver weight. The expression of lipid synthesis and catabolism genes, as well as profibrotic, endoplasmic reticulum stress, and oxidative stress genes were largely unaffected in the adipose tissue of Ctrp12 KO male mice. Despite greater adiposity and insulin resistance, Ctrp12 KO male mice fed an obesogenic diet had lower circulating triglyceride and free fatty acid levels. In contrast, lipid profiles of the leaner female KO mice were not different from those of WT controls. These data suggest that CTRP12 contributes to whole body energy metabolism in genotype-, diet-, and sex-dependent manners, underscoring complex gene-environment interactions influencing metabolic outcomes.

Regular Coffee Consumption Is Associated with Lower Regional Adiposity Measured by DXA among US Women

BACKGROUND

Coffee is among the most popular daily beverages in the United States. Importantly, coffee consumption has been associated with a lower risk of multiple health outcomes including a reduction in adiposity. DXA is a means to assess body fat and distribution.

OBJECTIVES

The aim of this study was to examine the relation between coffee consumption and DXA-assessed adiposity and adiposity distribution.

METHODS

Cross-sectional data from the NHANES were used. Participants were adults aged 20-69 y from the 2003-2004 and 2005-2006 waves. Information on coffee consumption was assessed through the FFQ (categorized as no coffee, 0 to <0.25 cup/d, 0.25 to <1 cup/d, 1 cup/d, 2-3 cups/d, or ≥4 cups/d). Both caffeinated and decaffeinated coffee consumption were included. Trunk fat and total fat percentage were measured via whole-body DXA scans. The association between coffee consumption and body fat was investigated using age-adjusted and multivariable-adjusted linear regression models which accounted for sample weights.

RESULTS

Higher coffee consumption was associated with significantly lower total body fat percentage and trunk body fat percentage in a dose-response manner (all P values < 0.05) among women. Although this dose-response relation was nonsignificant among men, men aged 20-44 y who drank 2-3 cups/d had 1.3% (95% CI: -2.7%, 0.1%) less total fat and 1.8% (95% CI: -3.3%, -0.4%) less trunk fat than those who did not consume coffee. Furthermore, the association between coffee consumption and body fat percentage exhibited for both caffeinated and decaffeinated coffee among women (all P for trend < 0.001) but not among men (all P for trend > 0.05).

CONCLUSIONS

The present study found a significant association between higher coffee consumption and lower DXA-measured adiposity. Moreover, a gender difference in this association in the general US adult population was also observed.

WAT-on-a-chip integrating human mature white adipocytes for mechanistic research and pharmaceutical applications

Obesity and its numerous adverse health consequences have taken on global, pandemic proportions. White adipose tissue (WAT) - a key contributor in many metabolic diseases - contributes about one fourth of a healthy human's body mass. Despite its significance, many WAT-related pathophysiogical mechanisms in humans are still not understood, largely due to the reliance on non-human animal models. In recent years, Organ-on-a-chip (OoC) platforms have developed into promising alternatives for animal models; these systems integrate engineered human tissues into physiological microenvironment supplied by a vasculature-like microfluidic perfusion. Here, we report the development of a novel OoC that integrates functional mature human white adipocytes. The WAT-on-a-chip is a multilayer device that features tissue chambers tailored specifically for the maintenance of 3D tissues based on human primary adipocytes, with supporting nourishment provided through perfused media channels. The platform's capability to maintain long-term viability and functionality of white adipocytes was confirmed by real-time monitoring of fatty acid uptake, by quantification of metabolite release into the effluent media as well as by an intact responsiveness to a therapeutic compound. The novel system provides a promising tool for wide-ranging applications in mechanistic research of WAT-related biology, in studying of pathophysiological mechanisms in obesity and diabetes, and in R&D of pharmaceutical industry.

Influence of Aging and Menstrual Status on Subcutaneous Fat Cell Lipolysis

CONTEXT

Aging is accompanied by inhibited fat cell mobilization of fatty acids through lipolysis, which may contribute to decreased energy expenditure in elderly subjects. However, the influence of menstrual status is unknown.

OBJECTIVE

To investigate the role of menstrual status on changes in lipolysis induced by aging.

DESIGN

A longitudinal investigation with a mean 13-year interval.

SETTING

Ambulatory study at a clinical academic unit.

PARTICIPANTS

Eighty-two continuously recruited women between 24 and 62 years of age and with body mass index 21 to 48 kg/m2 at first examination. Twenty-nine women continued to have normal menstruation, 42 developed irregular menstruation/menopause, and 11 had a perimenstrual/menopausal phenotype already at the first examination.

MAIN OUTCOME MEASURE

Lipolysis measured as glycerol release from isolated subcutaneous fat cells incubated in vitro.

RESULTS

On average, body weight/body fat mass levels did not change over time. In all 3 groups, aging was associated with a similar decrease in spontaneous (basal) and catecholamine-stimulated lipolysis. The latter was due to decreased signal transduction through stimulatory beta adrenoceptors and increased alpha-2-adrenoceptor-mediated antilipolytic effects. Gene microarray data from adipose tissue at baseline and follow-up (n = 53) showed that a limited set of lipolysis-linked genes, including phosphodiesterase-3B, were altered over time, but this was independent of menstrual status. Fat cell size also decreased during aging, but this could not explain the decrease in lipolysis.

CONCLUSIONS

In women, the rate of fat cell lipolysis decreases during aging due to multiple alterations in spontaneous (basal) and catecholamine-induced lipolysis. This is independent of changes in menstrual status or fat cell size.

Effect of high-fat diet on the various morphological parameters of the ovary

Increased food consumption rich in fat and carbohydrate and sedentary lifestyle have seriously increased the rates of obesity and obesity-associated diseases in developed countries. Female mice with diet-induced obesity exhibit infertility and thus can serve as a model for human polycystic ovary syndrome. The aim of the present study was to examine how ovary is affected by diet-induced obesity. The effects of high-fat diet (HFD) on ovary morphology in mice fed with HFD were investigated using unbiased stereological methods. The ovary of mice fed with HFD (n=8, C1090-60, Altromine) for 9 weeks, were compared with that of mice fed with standard chow diet (n=8, C1090-10, Altromine). Stereological parameters were obtained in diestrus cycle. The samples were processed through routine and standard paraffin embedding and were serially sectioned in 5-µm thickness then, every 10th section was saved, stained with Crossman's triple stain for counting and measuring. In all sampled sections mean follicle numbers, diameters, total ovarian volume cortex to medulla ratio (Vv), ovum to cell ratio in secondary follicle were examined in all sampled sections. The present results showed that weight of ovarian and amount of intraperitoneal adipose tissue and the body weight markedly increased in obese mice when compared with control groups. Moreover, follicle numbers (except primordial follicles) and diameters were significantly increased in obese mice. Cortex to medulla ratio (Vv) and ovum to cell ratio in secondary follicle were also considerably different between experimental and the control groups. The present findings indicate that obesity adversely affects overall ovarian morphology.

Peptides from Natural or Rationally Designed Sources Can Be Used in Overweight, Obesity, and Type 2 Diabetes Therapies

Overweight and obesity are among the most prominent health problems in the modern world, mostly because they are either associated with or increase the risk of other diseases such as type 2 diabetes, hypertension, and/or cancer. Most professional organizations define overweight and obesity according to individual body-mass index (BMI, weight in kilograms divided by height squared in meters). Overweight is defined as individuals with BMI from 25 to 29, and obesity as individuals with BMI ≥30. Obesity is the result of genetic, behavioral, environmental, physiological, social, and cultural factors that result in energy imbalance and promote excessive fat deposition. Despite all the knowledge concerning the pathophysiology of obesity, which is considered a disease, none of the existing treatments alone or in combination can normalize blood glucose concentration and prevent debilitating complications from obesity. This review discusses some new perspectives for overweight and obesity treatments, including the use of the new orally active cannabinoid peptide Pep19, the advantage of which is the absence of undesired central nervous system effects usually experienced with other cannabinoids.

Analysis of testis metabolome and transcriptome from the oriental river prawn (Macrobrachium nipponense) in response to different temperatures and illumination times

A better understanding of the mechanisms underlying the male sexual differentiation of Macrobrachium nipponense is urgently needed in order to maintain sustainable development of the M. nipponense industry. Environmental factors, especially temperature and illumination, have dramatic effects on gonadal development. The aim of the present study was to identify key genes and metabolites involved in the male sexual differentiation and development of M. nipponense through integrated metabolomics and transcriptome analyses of the testis in response to different temperatures and illumination times. A total of 268 differentially abundant metabolites and 11,832 differentially expressed genes (DEGs) were identified. According to integrated metabolomics and transcriptome analyses, glycerophospholipid and sphingolipid metabolism was predicted to have dramatic effects on the male sexual differentiation and development of M. nipponense. According to the KEGG enrichment analysis of DEGs, oxidative phosphorylation, glycolysis/gluconeogenesis, the HIF-1 signaling pathway, the citrate cycle, steroid hormone synthesis, and the spliceosome complex were predicted to promote male differentiation and development by providing adenosine triphosphate, promoting the synthesis of steroid hormones, and providing correct gene products. Quantitative polymerase chain reaction analysis and in situ hybridization showed that the SDHB, PDE1, HSDL1, CYP81F2, SRSF, and SNRNP40 genes were differentially expressed, suggesting roles in the male sexual differentiation and development of M. nipponense. Strong candidate sex-related metabolic pathways and genes in M. nipponense were identified by integrated metabolomics and transcriptome analyses of the testis in response to different temperatures and illumination times, as confirmed by PCR analysis and in situ hybridization.

Association of leptin and leptin receptor polymorphisms with coronary artery disease in a North Chinese Han population

INTRODUCTION:

Leptin (LEP) is a peptide hormone that acts via leptin receptor (LEPR) binding. Genetic evidence from different human populations has implicated LEP/LEPR in the pathogenesis of coronary artery disease (CAD), and suggests that certain LEP/LEPR gene polymorphisms may increase the risk of CAD. The aim of this study was to assess two single nucleotide polymorphisms (SNPs) in LEP genes (rs2167270 and rs7799039) and two in LEPR genes (rs6588147, rs1137100) for association with CAD.

METHODS:

We enrolled 271 North Chinese Han CAD patients, and 113 healthy age- and sex-matched controls. Genomic DNA was extracted from whole blood, and the four SNPs were assessed using a MassArray system.

RESULTS:

The G allele frequency at rs2167270 was significantly higher among CAD cases than among controls. The AG genotype at rs7799039 was associated with a significantly decreased risk of CAD unlike the AA genotype used as the reference. The A allele was significantly associated with the CAD patient group. Interestingly, statistically significant differences in genotype and allele frequency at LEP rs2167270 and rs7799039 existed among females but not among males.

CONCLUSIONS:

The current study detected a significant association between genetic variations at LEP rs7799039 and rs2167270 and the risk of CAD in a north Chinese population, and revealed that LEP rs2167270 and rs7799039 gene polymorphisms might act as predisposing factors for CAD.

Epigenetics, Gender, and Sex in the Diagnosis of Depression

Background :

A marked sexual dimorphism exists in psychiatric diagnoses. Culture derived gender bias in diagnostic criteria is one explanation. Adverse childhood events, including sexual and physical abuse, are more reliable and consistent predictors of later psychiatric diagnoses, including depression and post-traumatic stress disorder. Some interesting interactions between genes and experience have been uncovered, but the primary effect appears to be epigenetic with life experience altering gene expression and being transmitted to subsequent generations.

Objectives :

To determine if reconceptualizing depression as encompassing both internalizing and externalizing strategies would eliminate gender differences in the diagnosis of depression

Methods :

We reviewed 74 life stories of patients, collected during a study of the effect of physicians’ knowing patients’ life stories on the quality of the doctor-patient relationship. Looking at diagnoses, the prevalence of women to men was 2.9 to 1. We redefined depression as a response to being in a seemingly hopeless situation accompanied by despair, either externalizing ((more often diagnosed as substance use disorders, impulse control disorders, antisocial personality disorder, or bipolar disorder) or internalizing (the more standard diagnosis of depression). Then we reviewed these life stories from that perspective to determine how many would be diagnosed as depressed.

Results :

With this reconceptualization of depression, the sex ratio changed to 1.2 to 1.

Conclusions:

From this perspective, men and women are equally likely to respond to hopelessness, though men are more socialized to externalize and women to internalize. Considering depression in this way may help to better identify men at risk for suicide.

CO2 anesthesia on Drosophila survival in aging research

Carbon dioxide (CO₂ ) exposure is a common method of anesthesia in studies of Drosophila melanogaster. A number of negative side effects of CO₂ anesthesia have been reported. It is not clear whether the length of CO₂ anesthesia time affects Drosophila survival in aging research. Here, we examined the potential effect of the CO₂ anesthesia time length of 10-150 min. We found that long CO₂ exposure could lead to Drosophila death, more significant in males. The longer the anesthesia time is, the longer it takes for flies to wake up. Long-time CO₂ anesthesia can reduce the lifespan. Our stress tests showed that long-time CO₂ anesthesia can increase the average survival time in both males and females under starvation conditions, but can only increase female lifespan under H₂ O₂ oxidative stress. Long-time CO₂ anesthesia also significantly affects physiological traits, with spontaneous activity increased in females but decreased in males, and reduced female fecundity. Our study suggests that limiting the CO₂ anesthesia time and giving enough recovery time before performing physiological tests are important in Drosophila aging research.

Thyroid Stimulating Hormone (TSH) Is Associated With General and Abdominal Obesity: A Cohort Study in School-Aged Girls During Puberty in East China

Objectives: Although the association between thyroid stimulating hormone (TSH) and obesity in children has been investigated in several cross-sectional studies, no study evaluated this association among girls during puberty, which were in a key period closely related to the fluctuations of thyroid hormones and development of obesity. Therefore, we conducted a cohort study to investigate the association of general and abdominal obesity with TSH in girls during puberty. Setting and participants: A cohort study of 481 school-aged girls during puberty was conducted in four regions in east China, with a baseline survey in 2017 and a follow-up survey in 2019. Outcome measures: Anthropometric indexes including height, weight and waist circumference (WC) were measured, and body mass index (BMI) was then calculated. Blood samples were collected to determine TSH and free thyroxine (FT4). Results: Of the 474 girls at baseline survey, the prevalences of BMI-based general obesity and WC-based abdominal obesity were 19.8% (94/474) and 21.7% (103/474), respectively. Compared with normal weight girls, the median serum TSH level was significantly higher in general obese girls (P = 0.037), but not in central obese girls (P = 0.173). Multiple logistic regression models indicated that those in the highest tertile of serum TSH level had a significantly higher risk of BMI-based overweight/obesity (OR = 1.83, 95% CI 1.01 to 3.32) compared with the lowest tertile. Analyses from 435 girls prospectively followed-up for 2 years revealed that those with general or central obesity also had higher follow-up TSH level (P = 0.004 and P = 0.008, respectively). The TSH level for girls with general obesity at baseline but normal weight at follow-up was 0.45 mU/L (95% CI 0.11 to 0.79) higher than those with normal weight at baseline and follow-up. Conclusions: TSH was positively associated with both general and abdominal obesity among girls during puberty.

Association of Imaging-Based Body Fat Distribution and Mammographic Density in the Multiethnic Cohort Adiposity Phenotype Study

BACKGROUND

As the stronger association of obesity with postmenopausal breast cancer in Asian than white women may be due to body fat distribution, we examined the relation of adiposity measures with percent mammographic density (PMD), a strong predictor of breast cancer incidence.

METHODS

A total of 938 women from five ethnic groups (69.1 ± 2.7 years) in the Adiposity Phenotype Study (APS) underwent DXA and MRI imaging. PMD was assessed in routine mammograms using a computer-assisted method. Spearman correlation coefficients were computed and general linear models were applied to estimate regression coefficients (β) for PMD per 0.5 SD units of adiposity measures while adjusting for known confounders, including DXA total body fat.

RESULTS

For 701 (75%) of the participants (69.1 ± 2.7 years), valid mammograms were obtained. Whereas total body fat, the trunk-to-periphery fat ratio (TPFR), visceral fat (VAT), and subcutaneous fat (SAT) were inversely correlated with PMD (P < 0.0001), the VAT/SAT ratio correlated positively (r _spearman = 0.10; P = 0.01). In fully adjusted models, PMD remained inversely related to TPFR and SAT and disappeared for VAT, while it was strengthened for VAT/SAT (β = 0.51; P = 0.009). This relation was stronger in Japanese Americans than other ethnic groups.

CONCLUSIONS

This is the first study to show an association of a high VAT/SAT ratio with greater PMD, a marker of breast cancer risk after taking into account total body fat.

IMPACT

The results indicate a link between the propensity to accumulate VAT and the amount of fat in the breast (1-PMD), which may influence the relation of obesity with breast cancer incidence.

Lipedema: A Call to Action!

Lipedema is a chronic progressive disease characterized by abnormal fat distribution resulting in disproportionate, painful limbs. It almost exclusively affects women, leading to considerable disability, daily functioning impairment, and psychosocial distress. Literature shows both scarce and conflicting data regarding its prevalence. Lipedema has been considered a rare entity by several authors, though it may be a far more frequent condition than thought. Despite the clinical impact on women's health, lipedema is in fact mostly unknown, underdiagnosed, and too often misdiagnosed with other similarly presenting diseases. Polygenic susceptibility combined with hormonal, microvascular, and lymphatic disorders may be partly responsible for its development. Furthermore, consistent information on lipedema pathophysiology is still lacking, and an etiological treatment is not yet available. Weight loss measures exhibit minimal effect on the abnormal body fat distribution, resulting in eating disorders, increased obesity risk, depression, and other psychological complaints. Surgical techniques, such as liposuction and excisional lipectomy, represent therapeutic options in selected cases. This review aims to outline current evidence regarding lipedema epidemiology, pathophysiology, clinical presentation, differential diagnosis, and management. Increased awareness and a better understanding of its clinical presentation and pathophysiology are warranted to enable clinicians to diagnose and treat affected patients at an earlier stage.

Spirulina Platensis Affects Factors Involved in Spermatogenesis and Increases Ghrelin Receptors in Testis Tissue of Rats Fed a High-Fat Diet

Ghrelin is a peptide hormone which plays important role in maintaining growth hormone release and energy homeostasis in vertebrates. Spirulina platensis (SP) has antioxidant and hypolipidemic effects due to its ingredients. In this study we aimed to investigate the effects of SP on the testicular structure and relation between ghrelin and testosterone in the testis of rats fed a high fat diet (HFD). Sixty four young adult male rats were used and divided to 8 equal groups. Experimental groups received addition of 10% cholesterol (CHL), 43% hydrogenated vegetable oil (HVO) and 3% SP alone or in combination to basal diet while the control group received only basal diet. Serum ghrelin and testosterone levels were measured with ELISA. Receptors for ghrelin and androgen were detected with immunohistochemistry. For histomorphometric investigation, tubulus seminiferus, intertubular area, tubulus seminiferus lumen, Leydig cell nucleus, Sertoli cell nucleus, germ cell nucleus, spermatocyte nucleus and elongated spermatid volume densities were determined stereologically. Serum ghrelin level was increased especially in HVO and CHL combination group compared to the control while serum ghrelin levels were close to control levels in SP-received groups. Ghrelin receptor level was increased in tubulus seminiferus with HVO+CHL administration but this effect was, however, limited in HVO+CHL and SP challenged groups. HVO+CHL administration caused a significant decrease in Leydig cell nucleus volume density, as well as in all SP-received groups, compared to the control. Significantly increased spermatocyte nucleus volume density in cholesterol-receiving groups was decreased to control level with SP alone and its combinations.

Glucose-dependent insulinotropic polypeptide deficiency reduced fat accumulation and insulin resistance, but deteriorated bone loss in ovariectomized mice

Given the established roles of glucose-dependent insulinotropic polypeptide (GIP) in promoting fat storage and bone formation, we assessed the contribution of GIP to obesity and osteopenia in ovariectomized mice with a gene encoding green fluorescent protein (GFP) inserted into the GIP locus, in which GIP was either reduced (GIPgfp/+ ) or absent (GIPgfp/gfp ). In GIPgfp/gfp mice, weight gain, subcutaneous and visceral fat mass were reduced, and glucose intolerance was improved compared with wild-type mice with the same magnitude of insulin responses. Cancellous bone mineral density and bone cortical thickness were reduced in GIPgfp/gfp mice compared with wild-type mice. In GIPgfp/+ mice, weight gain, glucose intolerance and cancellous bone mineral density were not different from that of wild-type mice. These results indicate that the total elimination of GIP ameliorates weight gain and adiposity in ovariectomized mice, but it enhances osteopenia, particularly in cancellous bone by partly suppressing bone formation.

A case-control study of the relationship between visceral fat and development of uterine fibroids

Relationship between visceral fat and development of uterine fibroids in adult women was investigated. A total of 89 patients with uterine fibroids treated in the First Hospital of Hebei Medical University from April 2016 to April 2018 were enrolled. Another 81 healthy women without uterine fibroids receiving physical examination in the same period were selected as the control group. Self-designed questionnaires were used to investigate the general conditions of the subjects, bioelectrical impedance analysis was employed to analyze obesity-related indicators, and their correlation with the risk of uterine fibroids was explored. Visceral fat area (VFA), body mass index (BMI), body fat percentage, waist circumference, waist-height ratio and waist-hip ratio were positively correlated with the incidence rate of uterine fibroids, and the odds ratio (OR), 95% confidence interval (CI) was 3.910 (2.029, 7.536), 2.716 (1.444, 5.110), 4.335 (1.507, 12.469), 2.881 (1.531, 5.423), 3.837 (1.914, 7.692) and 7.707 (3.501, 16.965), respectively. VFA and body fat percentage were correlated with the size of uterine fibroids, but the correlations were relatively weak. With the increase in the VFA, BMI, waist circumference, waist-height ratio, and waist-hip ratio, the risk of uterine fibroids was elevated. The BMI, VFA and waist circumference of patients with uterine fibroids were gradually increased with increasing age, showing statistically significant differences. Increased body fat (especially abdominal visceral fat) is able to enhance the risk of uterine fibroids. For perimenopausal women, the waist-hip ratio measured can be used as an indicator screening high-risk groups of uterine fibroids. This method is simple, easy and inexpensive. At the same time, providing nutrition guidance and changing diet and exercise habits are important measures to prevent the development of uterine fibroids.

Discriminative ability of adiposity measures for elevated blood pressure among adolescents in a resource-constrained setting in northeast Nigeria: a cross-sectional analysis

Background

Several studies examining the association and discriminative ability of adiposity measures for prehypertension and hypertension among adolescents have reported varying outcomes. We aimed to determine the discriminative ability of the Body Mass index (BMI), Waist Circumference (WC), and Waist-to-Height Ratio (WHtR) adiposity measures for elevated blood pressure (prehypertension and hypertension combined) among adolescents in Gombe, northeast Nigeria.

Methods

This cross-sectional study used a multi-stage sampling technique and involved 367 secondary school adolescent (10–18 years) boys and girls in Gombe Local Government Area, Gombe State, northeast Nigeria from January to September 2015. We examined and compared the associations and discriminative ability of the BMI, WC and the WHtR for elevated blood pressure using multiple logistic regression and receiver operating characteristics (ROC) curves. Area under the curves (AUC), odds ratio (OR) and 95% confidence intervals (CI) are reported.

Results

All three measures of adiposity were strongly and positively associated with elevated blood pressure. The BMI obesity showed the strongest association with elevated blood pressure with odds that was double the odds of WC and triple that of WHtR [adjusted OR for BMI 15.3, 95% CI (4.8–27.9)]. The discriminative ability of adiposity measures for elevated blood pressure using AUC was comparable (0.786 for BMI, vs 0.780 for WC, vs 0.761 for WHtR).

Conclusion

We provide evidence, here on the BMI, WC and WHtR to support the use of simple indirect measures of adiposity in evaluating adiposity-related risk including prehypertension and hypertension among Nigerian adolescents.

Electronic supplementary material

The online version of this article (10.1186/s40608-018-0211-7) contains supplementary material, which is available to authorized users.

aP2-Cre Mediated Ablation of GHS-R Attenuates Adiposity and Improves Insulin Sensitivity during Aging

Ghrelin via its receptor, the growth hormone secretagogue receptor (GHS-R), increases food intake and adiposity. The tissue-specific functions of GHS-R in peripheral tissues are mostly unknown. We previously reported that while GHS-R expression is very low in white and brown fat of young mice, expression increases during aging. To investigate whether GHS-R has cell-autonomous effects in adipose tissues, we generated aP2-Cre-mediated GHS-R knockdown mice (aP2-Cre/Ghsr^f/f). We studied young (5–6 months) and old (15–17 months) aP2-Cre/Ghsr^f/f mice and their age-matched controls. Interestingly, young aP2-Cre/Ghsr^f/f mice had normal body weight but reduced fat; old mice showed pronounced reductions of both body weight and body fat. Calorimetry analysis revealed that aP2-Cre/Ghsr^f/f mice had normal food intake and locomotor activity at both young and old age; but intriguingly, while energy expenditure was normal at young age, it was significantly increased at old age. Both young and old aP2-Cre/Ghsr^f/f mice exhibited improved insulin sensitivity and glucose tolerance. Importantly, old aP2-Cre/Ghsr^f/f mice maintained higher core body temperature at 4 °C, and showed higher expression of the thermogenic uncoupling protein 1 (UCP1) gene. The ex vivo studies further demonstrated that GHS-R deficient white adipocytes from old mice exhibit increased glucose uptake and lipolysis, promoting lipid mobilization. Despite the fact that the in vivo phenotypes of aP2-Cre/Ghsr^f/f mice may not be exclusively determined by GHS-R knockdown in adipose tissues, our data support that GHS-R has cell-autonomous effects in adipocytes. The anabolic effect of GHS-R in adipocytes is more pronounced in aging, which likely contributes to age-associated obesity and insulin resistance.

Lipidomic analysis reveals significant lipogenesis and accumulation of lipotoxic components in ob/ob mouse organs

To further understand the role of lipogenesis and lipotoxicity in the development of obesity and diabetes, lipidomes of various organs from ob/ob mice and their wild type controls were analyzed by shotgun lipidomics at 10, 12, and 16 weeks of age. We observed that the amounts of fatty acyl (FA) chains corresponding to those from de novo synthesis (e.g., 16:0, 16:1, and 18:1 FA) were substantially elevated in ob/ob mice, consistent with increased expression of genes and proteins involved in biosynthesis. Polyunsaturated fatty acid species were moderately increased in the examined tissues of ob/ob mice, since they can only be absorbed from diets or elongated from the ingested n-3 or n-6 FA. Different profiles of FA chains between ob/ob mouse liver and skeletal muscle reflect diverging lipogenesis pathways in these organs. Amounts of vaccenic acids (i.e., 18:1(n-7) FA) in 12- and 16-week ob/ob mouse liver were significantly increased compared to their controls, indicating enhanced de novo synthesis of this acid through 16:1(n-7) FA in the liver starting at 12 weeks of age. Coincidentally, synthesis of triacylglycerol from monoacylglycerol in the liver was also increased in ob/ob mice starting at 12 weeks of age, as revealed by simulation of triacylglycerol synthesis. Moreover, levels of lipotoxic lipid classes were significantly higher in ob/ob mice than their age-matched controls, supporting the notion that elevated lipotoxic components are tightly associated with insulin resistance in ob/ob mice. Taken together, the current study revealed that lipogenesis and lipotoxicity in ob/ob mice likely contribute to insulin resistance and provides great insights into the underlying mechanisms of diabetes and obesity.

Gonadectomy in Mito-Ob mice revealed a sex-dimorphic relationship between prohibitin and sex steroids in adipose tissue biology and glucose homeostasis

Background

Recently, we have developed a novel transgenic mouse model by overexpressing prohibitin (PHB) in adipocytes, which developed obesity due to upregulation of mitochondrial biogenesis in adipocytes, hence named “Mito-Ob.” Interestingly, only male Mito-Ob mice developed obesity-related impaired glucose homeostasis and insulin sensitivity, whereas female Mito-Ob mice did not. The observed sex differences in metabolic dysregulation suggest a potential involvement of sex steroids. Thus, the main aim of this study is to investigate the role of sex steroids on the overall phenotype of Mito-Ob mice through gonadectomy, as well as direct effect of sex steroids on adipocytes from Mito-Ob mice in vitro.

Methods

Mito-Ob mice and wild-type CD-1 mice were gonadectomized at 12 weeks of age. Age- and sex-matched sham-operated mice were used as controls. Body weight, white adipose tissue, glucose tolerance, and insulin sensitivity were analyzed 3 months post-surgery. Differentiation of adipocytes isolated from female and male Mito-Ob mice were studied with and without sex steroids.

Results

Gonadectomy significantly reduced body weight in Mito-Ob mice compared with sham-operated mice, whereas the opposite trend was observed in wild-type mice. These changes occurred independent of food intake. A corresponding decrease in adipose tissue weight was found in gonadectomized Mito-Ob mice, but depot-specific differences were observed in male and female. Gonadectomy improved glucose tolerance in male wild-type and Mito-Ob mice, but the effect was more pronounced in wild-type mice. Gonadectomy did not alter insulin sensitivity in male Mito-Ob mice, but it was improved in male wild-type mice. In primary cell cultures, testosterone inhibited adipocyte differentiation to a lesser extent in male Mito-Ob preadipocytes compared with the wild-type mice. On the other hand, preadipocytes from female wild-type mice showed better differentiation potential than those from female Mito-Ob mice in the presence of 17β-estradiol.

Conclusions

PHB requires sex steroids for the development of obese phenotype in Mito-Ob mice, which differentially affect glucose homeostasis and insulin sensitivity in male and female. It appears that PHB plays sex- and adipose depot-specific roles and involves additional factors. In vitro studies suggested that PHB differently influenced adipocyte differentiation in the presence and absence of sex steroids. Overall, this study along with available information in the literature indicated that a multifaceted relationship exists between PHB and sex steroids, which may work in a cell/tissue type- and sex-specific manner.

Determinants of body fat distribution in humans may provide insight about obesity-related health risks

Obesity increases the risks of developing cardiovascular and metabolic diseases and degrades quality of life, ultimately increasing the risk of death. However, not all forms of obesity are equally dangerous: some individuals, despite higher percentages of body fat, are at less risk for certain chronic obesity-related complications. Many open questions remain about why this occurs. Data suggest that the physical location of fat and the overall health of fat dramatically influence disease risk; for example, higher concentrations of visceral relative to subcutaneous adipose tissue are associated with greater metabolic risks. As such, understanding the determinants of the location and health of adipose tissue can provide insight about the pathological consequences of obesity and can begin to outline targets for novel therapeutic approaches to combat the obesity epidemic. Although age and sex hormones clearly play roles in fat distribution and location, much remains unknown about gene regulation at the level of adipose tissue or how genetic variants regulate fat distribution. In this review, we discuss what is known about the determinants of body fat distribution, and we highlight the important roles of sex hormones, aging, and genetic variation in the determination of body fat distribution and its contribution to obesity-related comorbidities.

Gender and Sex Differences in Adipose Tissue

PURPOSE OF REVIEW

As the ongoing epidemic of adult and childhood obesity grows, it puts a greater burden on individuals and the healthcare system due to increased prevalence of obesity-associated diseases. An important area that has gained much attention recently is the sex and gender difference related to obesity and associated complications. Basic science and clinical studies have now improved our understanding of obesity and have discovered adipose tissue biology to be key in metabolism.

RECENT FINDINGS

There is evidence related to the sex dichotomy in obesity in a variety of areas including adipocyte function, sex hormone effects, genetics, and metabolic inflammation leading to critical differences in adipose tissue biology. The sex and gender difference in adipose tissue is a factor that should be considered when studying an individuals' risk for obesity and metabolic dysfunction. This understanding is important for strategizing treatment and prevention measures.

FGFR1 underlies obesity-associated progression of estrogen receptor-positive breast cancer after estrogen deprivation

Obesity increases breast cancer mortality by promoting resistance to therapy. Here, we identified regulatory pathways in estrogen receptor-positive (ER-positive) tumors that were shared between patients with obesity and those with resistance to neoadjuvant aromatase inhibition. Among these was fibroblast growth factor receptor 1 (FGFR1), a known mediator of endocrine therapy resistance. In a preclinical model with patient-derived ER-positive tumors, diet-induced obesity promoted a similar gene expression signature and sustained the growth of FGFR1-overexpressing tumors after estrogen deprivation. Tumor FGFR1 phosphorylation was elevated with obesity and predicted a shorter disease-free and disease-specific survival for patients treated with tamoxifen. In both human and mouse mammary adipose tissue, FGF1 ligand expression was associated with metabolic dysfunction, weight gain, and adipocyte hypertrophy, implicating the impaired response to a positive energy balance in growth factor production within the tumor niche. In conjunction with these studies, we describe a potentially novel graft-competent model that can be used with patient-derived tissue to elucidate factors specific to extrinsic (host) and intrinsic (tumor) tissue that are critical for obesity-associated tumor promotion. Taken together, we demonstrate that obesity and excess energy establish a tumor environment with features of endocrine therapy resistance and identify a role for ligand-dependent FGFR1 signaling in obesity-associated breast cancer progression.

Gut Microbiota Markers in Obese Adolescent and Adult Patients: Age-Dependent Differential Patterns

Obesity levels, especially in children, have dramatically increased over the last few decades. Recently, several studies highlighted the involvement of gut microbiota in the pathophysiology of obesity. We investigated the composition of gut microbiota in obese adolescents and adults compared to age-matched normal weight (NW) volunteers in order to assemble age- and obesity-related microbiota profiles. The composition of gut microbiota was analyzed by 16S rRNA-based metagenomics. Ecological representations of microbial communities were computed, and univariate, multivariate, and correlation analyses performed on bacterial profiles. The prediction of metagenome functional content from 16S rRNA gene surveys was carried out. Ecological analyses revealed a dissimilarity among the subgroups, and resultant microbiota profiles differed between obese adolescents and adults. Using statistical analyses, we assigned, as microbial markers, Faecalibacterium prausnitzii and Actinomyces to the microbiota of obese adolescents, and Parabacteroides, Rikenellaceae, Bacteroides caccae, Barnesiellaceae, and Oscillospira to the microbiota of NW adolescents. The predicted metabolic profiles resulted different in adolescent groups. Particularly, biosynthesis of primary bile acid and steroid acids, metabolism of fructose, mannose, galactose, butanoate, and pentose phosphate and glycolysis/gluconeogenesis were for the majority associated to obese, while biosynthesis and metabolism of glycan, biosynthesis of secondary bile acid, metabolism of steroid hormone and lipoic acid were associated to NW adolescents. Our study revealed unique features of gut microbiota in terms of ecological patterns, microbial composition and metabolism in obese patients. The assignment of novel obesity bacterial markers may open avenues for the development of patient-tailored treatments dependent on age-related microbiota profiles.

Bone mineral density and body composition in children with congenital adrenal hyperplasia

OBJECTIVE

Children with congenital adrenal hyperplasia (CAH) are exposed to fluctuating cortisol and androgen levels. The effects these hormonal states have on bone mineral density (BMD) and body composition are not well studied. The study's objective was to compare BMD and body composition, including visceral adipose tissue (VAT) and Android:Gynoid (A:G) ratio, in children with CAH vs healthy age-matched, sex-matched and BMI-matched controls.

DESIGN

Total body BMD (TBMD) Z-scores were adjusted for height-for-age Z-scores (TBMDHAZ). Hydrocortisone dose (mg/m2/d) was averaged over the past year. Bone age Z-scores were used as a surrogate for long-term androgen exposure in cases. Statistical analyses comparing cases and controls accounted for matched groups using mixed linear models.

PATIENTS

Forty-two cases with CAH (average age 12.3 years [SE 3]; 17 males) and 101 controls underwent a dual-energy X-ray absorptiometry scan.

RESULTS

Children with CAH had lower TBMD (0.81 vs 1.27, P = .003) and TBMDHAZ Z-scores (-0.51 vs -0.01, P = .001) than controls. In CAH cases, TBMD and TBMDHAZ Z-scores were positively correlated with bone age Z-scores (r = .63, P < .0001; r = .51, P = .001, respectively) but were not associated with HC dose. VAT and the A:G ratio did not differ significantly between children with CAH and controls and neither was associated with HC dose.VAT was not associated with bone age Z-score.

CONCLUSION

Lower BMD was observed in CAH cases compared with controls although no differences in body composition were identified. Among CAH cases, increased chronic androgen exposure, as measured by bone age Z-scores, was associated with higher BMD but was not associated with VAT.

Effect of High-Fat Diet on Immature Female Mice and Messenger and Noncoding RNA Expression Profiling in Ovary and White Adipose Tissue

Obesity is a chronic multifactorial disease prevalent in many areas of the world and is a major cause of morbidity and mortality. In women, obesity increases the risks of both metabolic and reproductive diseases, such as diabetes and infertility. The mechanisms underlying these effects, especially in young women, are largely unknown. To explore these mechanisms, we established a high-fat diet (HFD) model of obesity in immature female mice. Microarray analysis of gene expression in ovaries and white adipose tissue identified a large number of differentially expressed genes (>1.3-fold change) in both tissues. In ovaries of the HFD group, there were 208 differentially expressed messenger RNAs (mRNAs), including 98 upregulated and 110 downregulated, and 295 differentially expressed lncRNAs (long non coding RNAs), including 63 upregulated and 232 downregulated. In white adipose tissue, there were 625 differentially expressed mRNAs, including 220 upregulated and 605 downregulated in the HFD group, and 1595 differentially expressed lncRNAs, including 1320 and 275 downregulated in the HFD group. Our results reveal significant differences between the transcriptomes of the HFD and control groups in both ovaries and white adipose tissue that provide clues to the molecular mechanisms of diet-induced female reproductive dysfunction and metabolic disorders, as well as biomarkers of risk for these disorders.

Inhibitor of Differentiation-3 and Estrogenic Endocrine Disruptors: Implications for Susceptibility to Obesity and Metabolic Disorders

The rising global incidence of obesity cannot be fully explained within the context of traditional risk factors such as an unhealthy diet, physical inactivity, aging, or genetics. Adipose tissue is an endocrine as well as a metabolic organ that may be susceptible to disruption by environmental estrogenic chemicals. Since some of the endocrine disruptors are lipophilic chemicals with long half-lives, they tend to bioaccumulate in the adipose tissue of exposed populations. Elevated exposure to these chemicals may predispose susceptible individuals to weight gain by increasing the number and size of fat cells. Genetic studies have demonstrated that the transcriptional regulator inhibitor of differentiation-3 (ID3) promotes high fat diet-induced obesity in vivo. We have shown previously that PCB153 and natural estrogen 17β-estradiol increase ID3 expression. Based on our findings, we postulate that ID3 is a molecular target of estrogenic endocrine disruptors (EEDs) in the adipose tissue and a better understanding of this relationship may help to explain how EEDs can lead to the transcriptional programming of deviant fat cells. This review will discuss the current understanding of ID3 in excess fat accumulation and the potential for EEDs to influence susceptibility to obesity or metabolic disorders via ID3 signaling.

Gender in Endocrine Diseases: Role of Sex Gonadal Hormones

Gender- and sex- related differences represent a new frontier towards patient-tailored medicine, taking into account that theoretically every medical specialty can be influenced by both of them. Sex hormones define the differences between males and females, and the different endocrine environment promoted by estrogens, progesterone, testosterone, and their precursors might influence both human physiology and pathophysiology. With the term Gender we refer, instead, to behaviors, roles, expectations, and activities carried out by the individual in society. In other words, "gender" refers to a sociocultural sphere of the individual, whereas "sex" only defines the biological sex. In the last decade, increasing attention has been paid to understand the influence that gender can have on both the human physiology and pathogenesis of diseases. Even the clinical response to therapy may be influenced by sex hormones and gender, but further research is needed to investigate and clarify how they can affect the human pathophysiology. The path to a tailored medicine in which every patient is able to receive early diagnosis, risk assessments, and optimal treatments cannot exclude the importance of gender. In this review, we have focused our attention on the involvement of sex hormones and gender on different endocrine diseases.

Sexually dimorphic effects of dietary sugar on lifespan, feeding and starvation resistance in Drosophila

Lifespan and health in older age are strongly influenced by diet. Feeding Drosophila melanogaster diets high in sugar has increasingly been used as an experimental model to understand the physiological effects of unhealthy, contemporary human diets. Several metabolic parameters and physiological responses to nutrition are known to be dependent on the sex of the animal. However, sexual dimorphism in the responses to high-sugar diets in fruit flies has not been examined. Here we show that a high-sugar diet in Drosophila melanogaster elicits sexually dimorphic effects on feeding behaviour, starvation resistance and lifespan. Females feed less on such diets, while males feed more, and these feeding responses may have secondary consequences. Females, more than males, gain the ability to resist periods of starvation from high-sugar diets, indicating that the female response to excess sugar may be geared towards surviving food shortages in early life. At the same time, female lifespan is more susceptible to the detrimental effects of high sugar diets. Our study reveals differences between Drosophila sexes in their responses to sugar-rich diets, indicating the fruit fly could be used as a model to understand the sexually dimorphic features of human metabolic health.

Sex-Specific Modulation of Fetal Adipogenesis by Gestational Bisphenol A and Bisphenol S Exposure

The endocrine-disrupting chemical bisphenol A (BPA) increases adipose tissue mass in vivo and promotes adipogenesis in vitro; however, mechanisms explaining BPA's obesogenic effect remain unknown. We investigated the effects of gestational BPA and its analog, bisphenol S (BPS), exposure on the adipogenic differentiation ability of fetal preadipocytes and the role of endoplasmic reticulum stress in regulating this process. Pregnant sheep (n = 7 to 8 per group) mated to the same male were exposed to BPA or BPS from days 30 to 100 of gestation; pregnancies were terminated 20 days later. Adipose tissue was harvested and fetal preadipocytes isolated. Adipose tissue gene expression, adipocyte size, preadipocyte gene expression, adipogenic differentiation, and dynamic expression of genes involved in adipogenesis and endoplasmic reticulum stress were assessed. Gestational BPA enhanced adipogenic differentiation in female, but not male, preadipocytes. The unfolded protein response (UPR) pathway was upregulated in BPA-exposed female preadipocytes supportive of a higher endoplasmic reticulum stress. Increased expression of estradiol receptor 1 and glucocorticoid receptor in female preadipocytes suggests that this may be a potential cause behind the sex-specific effects observed upon BPA exposure. Gestational BPS affected adipogenic terminal differentiation gene expression in male preadipocytes, but not adipogenic differentiation potential. We demonstrate that gestational BPA exposure can modulate the differentiation ability of fetal preadipocytes. UPR upregulation in gestationally BPA-exposed female preadipocytes may contribute to the increased preadipocyte's adipogenic ability. The marked sex-specific effect of BPA highlights higher susceptibility of females to bisphenol A and potentially, a higher risk to develop obesity in adulthood.

Sex Steroid Hormones Regulate Leptin Transcript Accumulation and Protein Secretion in 3T3-L1 Cells

Leptin is an adipokine produced by fat cells that regulates food consumption and metabolic activity. Sexual dimorphism in leptin and fat stores have been observed in humans and rodents with females having more leptin and greater levels of subcutaneous fat than males. One potential mechanism leading to this dimorphism is steroid hormone regulated synthesis of transcripts encoding leptin. Identification of direct regulatory mechanisms is difficult in animals or primary adipocytes due to these intertwined dimorphisms. We used well-characterized 3T3-L1 murine adipocytes to demonstrate that dihydrotestosterone (DHT) reduced Leptin (Lep) transcript abundance and cytosolic and secreted leptin protein. The magnitude of this effect was greatest on secreted leptin, which was decreased by DHT to 30% of the control. In contrast, 17β-estradiol significantly increased the abundance of transcripts encoding leptin and increased secreted leptin to 230% of the control. Treatment with estrogen and androgen receptor antagonists had opposite effects on Lep transcript abundance to steroid treatments, indicating that these transcriptional effects are mediated through the canonical steroid hormone signaling pathways. These results indicate that short-term treatments with steroid hormones are sufficient to alter both Lep transcript accumulation and leptin protein secretion, and may play a role in the sexual dimorphism of this adipokine.

The adipose tissue-derived stromal vascular fraction cells from lipedema patients: Are they different?

BACKGROUND AIMS

Lipedema is a hormone-related disease of women characterized by enlargement of the extremities caused by subcutaneous deposition of adipose tissue. In healthy patients application of autologous adipose tissue-derived cells has shown great potential in several clinical studies for engrafting of soft tissue reconstruction in recent decades. The majority of these studies have used the stromal vascular fraction (SVF), a heterogeneous cell population containing adipose-derived stromal/stem cells (ASC), among others. Because cell identity and regenerative properties might be affected by the health condition of patients, we characterized the SVF cells of 30 lipedema patients in comparison to 22 healthy patients.

METHODS

SVF cells were analyzed regarding cell yield, viability, adenosine triphosphate content, colony forming units and proliferative capacity, as well as surface marker profile and differentiation potential in vitro.

RESULTS

Our results demonstrated a significantly enhanced SVF cell yield isolated from lipedema compared with healthy patients. In contrast, the adipogenic differentiation potential of SVF cells isolated from lipedema patients was significantly reduced compared with healthy patients. Interestingly, expression of the mesenchymal marker CD90 and the endothelial/pericytic marker CD146 was significantly enhanced when isolated from lipedema patients.

DISCUSSION

The enhanced number of CD90⁺ and CD146⁺ cells could explain the increased cell yield because the other tested surface marker were not reduced in lipedema patients. Because the cellular mechanism and composition in lipedema is largely unknown, our findings might contribute to a better understanding of its etiology.

Effects of cold sensitivity in the extremities on circulating adiponectin levels and metabolic syndrome in women

Background

In adipose tissues, adipokine levels, including adiponectin and leptin, are involved in insulin sensitivity and are reciprocally induced by cold temperature stress. Thermogenic response in the extremities (hands and feet) against cold stress can be negatively related to fat mass accumulation, particularly in the abdomen. However, the relationship between the sensation of cold in the extremities and circulating levels of adipokines is not fully understood. Here, we investigated whether adipokine levels are associated with cold hypersensitivity in the hands and feet (CHHF), independent of body mass, and whether the CHHF is related to metabolic syndrome (MS).

Methods

Associations of the CHHF with serum levels of adipokines and MS risk were evaluated in 1021 Koreans (372 men and 649 women), using a linear regression model while controlling for thermogenic factors and a logistic regression model, respectively.

Results

The adiponectin levels were positively associated with the CHHF, particularly in women, irrespective of thermogenic factors, including body mass index (β = 1.23 μg/mL, 95% confidence interval [1.04–1.45]). Logistic regression analysis for MS risk via the CHHF showed that there was a significant inverse association in women (odds ratio = 0.449, 95% confidence interval [0.273–0.737]).

Conclusions

In summary, our founding indicated that the CHHF could induce increased levels of circulating adiponectin and in turn reduce the MS risk in women. Despite complaints of feeling cold, these women could be at lower risk of cardiovascular disease.

Integrating insulin-like growth factor 1 and sex hormones into neuroprotection: Implications for diabetes

Brain integrity and cognitive aptitude are often impaired in patients with diabetes mellitus, presumably a result of the metabolic complications inherent to the disease. However, an increasing body of evidence has demonstrated the central role of insulin-like growth factor 1 (IGF1) and its relation to sex hormones in many neuroprotective processes. Both male and female patients with diabetes display abnormal IGF1 and sex-hormone levels but the comparison of these fluctuations is seldom a topic of interest. It is interesting to note that both IGF1 and sex hormones have the ability to regulate phosphoinositide 3-kinase-Akt and mitogen-activated protein kinases-extracellular signal-related kinase signaling cascades in animal and cell culture models of neuroprotection. Additionally, there is considerable evidence demonstrating the neuroprotective coupling of IGF1 and estrogen. Androgens have also been implicated in many neuroprotective processes that operate on similar signaling cascades as the estrogen-IGF1 relation. Yet, androgens have not been directly linked to the brain IGF1 system and neuroprotection. Despite the sex-specific variations in brain integrity and hormone levels observed in diabetic patients, the IGF1-sex hormone relation in neuroprotection has yet to be fully substantiated in experimental models of diabetes. Taken together, there is a clear need for the comprehensive analysis of sex differences on brain integrity of diabetic patients and the relationship between IGF1 and sex hormones that may influence brain-health outcomes. As such, this review will briefly outline the basic relation of diabetes and IGF1 and its role in neuroprotection. We will also consider the findings on sex hormones and diabetes as a basis for separately analyzing males and females to identify possible hormone-induced brain abnormalities. Finally, we will introduce the neuroprotective interplay of IGF1 and estrogen and how androgen-derived neuroprotection operates through similar signaling cascades. Future research on both neuroprotection and diabetes should include androgens into the interplay of IGF1 and sex hormones.

Diet, gonadal sex, and sex chromosome complement influence white adipose tissue miRNA expression

BACKGROUND

MicroRNAs (miRNAs) are small non-coding RNA molecules that regulate gene expression by targeting specific mRNA species for degradation or interfering with translation. Specific miRNAs are key regulators of adipogenesis, and are expressed at different levels in adipose tissue from lean and obese mice. The degree of lipid accumulation and distribution of white adipose tissue differs between males and females, and it is unknown whether sex differences in adipose tissue-specific miRNA expression may contribute to this dimorphism. Typically, sex differences are attributed to hormones secreted from ovaries or testes. However, the sex chromosome complement (XX versus XY) is also a determinant of sex differences and may regulate miRNA expression in adipocytes.

RESULTS

To identify sex differences in adipose tissue miRNA expression and to understand the underlying mechanisms, we performed high-throughput miRNA sequencing in gonadal fat depots of the Four Core Genotypes mouse model. This model, which consists of XX female, XX male, XY female, and XY male mice, allowed us to assess independent effects of gonadal type (male vs. female) and sex chromosome complement (XX vs. XY) on miRNA expression profiles. We have also assessed the effects of a high fat diet on sex differences in adipose tissue miRNA profiles. We identified a male-female effect on the overall miRNA expression profile in mice fed a chow diet, with a bias toward higher expression in male compared to female gonadal adipose tissue. This sex bias disappeared after gonadectomy, suggesting that circulating levels of gonadal secretions modulate the miRNA expression profile. After 16 weeks of high fat diet, the miRNA expression distribution was shifted toward higher expression in XY vs. XX adipose tissue. Principal component analysis revealed that high fat diet has a substantial effect on miRNA profile variance, while gonadal secretions and sex chromosome complement each have milder effects.

CONCLUSIONS

Our results demonstrate that the overall miRNA expression profile in adipose tissue is influenced by gonadal hormones and the sex chromosome complement, and that expression profiles change in response to gonadectomy and high fat diet. Differential miRNA expression profiles may contribute to sex differences in adipose tissue gene expression, adipose tissue development, and diet-induced obesity.

The Body Fat-Cognition Relationship in Healthy Older Individuals: Does Gynoid vs Android Distribution Matter?

OBJECTIVE

To examine the relationship between regional and whole body fat accumulation and core cognitive executive functions.

DESIGN

Cross-sectional study.

SETTINGS AND PARTICIPANTS

78 healthy men and women aged between 65 and 75 years recruited through consumer's database.

MEASUREMENTS

DXA measured percentage total body fat, android, gynoid distribution and android/gynoid ratio; inhibition and working memory updating through Random Number Generation test and cognitive flexibility by Trail Making test. First-order partial correlations between regional body fat and cognitive executive function were computed partialling out the effects of whole body fat. Moderation analysis was performed to verify the effect of gender on the body fat-cognition relationship.

RESULTS

Results showed a differentiated pattern of fat-cognition relationship depending on fat localization and type of cognitive function. Statistically significant relationships were observed between working memory updating and: android fat (r = -0.232; p = 0.042), gynoid fat (r = 0.333; p = 0.003) and android/gynoid ratio (r = -0.272; p = 0.017). Separating genders, the only significant relationship was observed in females between working memory updating and gynoid fat (r = 0.280; p = 0.045). In spite of gender differences in both working memory updating and gynoid body fat levels, moderation analysis did not show an effect of gender on the relationship between gynoid fat and working memory updating.

CONCLUSIONS

Results suggest a protective effect of gynoid body fat and a deleterious effect of android body fat. Although excessive body fat increases the risk of developing CDV, metabolic and cognitive problems, maintaining a certain proportion of gynoid fat may help prevent cognitive decline, particularly in older women. Guidelines for optimal body composition maintenance for the elderly should not target indiscriminate weight loss, but weight maintenance through body fat/lean mass control based on non-pharmacological tools such as physical exercise, known to have protective effects against CVD risk factors and age-related cognitive deterioration.

The Role of Sex and Sex Hormones in Regulating Obesity-Induced Inflammation

Metabolic and non-metabolic complications due to obesity are becoming more prevalent, yet our understanding of the mechanisms driving these is not. This is due to individual risk factor variability making it difficult to predict disease outcomes such as diabetes and insulin resistance. Gender is a critical factor in obesity outcomes with women having more adiposity but reduced metabolic complications compared to men. The role of immune system activation during obesity is an emerging field that links adiposity to metabolic syndrome. Furthermore, evidence from animal models suggests that sex differences exist in immune responses and, therefore, could be a possible mechanism leading to sex differences in metabolic disease. While there is still much to learn in the area of sex-differences research, this chapter will review the current knowledge and literature detailing the role of sex and sex hormones on adiposity and metabolically induced inflammation in obesity.

Loss of CTRP1 disrupts glucose and lipid homeostasis

C1q/TNF-related protein 1 (CTRP1) is a conserved plasma protein of the C1q family with notable metabolic and cardiovascular functions. We have previously shown that CTRP1 infusion lowers blood glucose and that transgenic mice with elevated circulating CTRP1 are protected from diet-induced obesity and insulin resistance. Here, we used a genetic loss-of-function mouse model to address the requirement of CTRP1 for metabolic homeostasis. Despite similar body weight, food intake, and energy expenditure, Ctrp1 knockout (KO) mice fed a low-fat diet developed insulin resistance and hepatic steatosis. Impaired glucose metabolism in Ctrp1 KO mice was associated with increased hepatic gluconeogenic gene expression and decreased skeletal muscle glucose transporter glucose transporter 4 levels and AMP-activated protein kinase activation. Loss of CTRP1 enhanced the clearance of orally administered lipids but did not affect intestinal lipid absorption, hepatic VLDL-triglyceride export, or lipoprotein lipase activity. In contrast to triglycerides, hepatic cholesterol levels were reduced in Ctrp1 KO mice, paralleling the reduced expression of cholesterol synthesis genes. Contrary to expectations, when challenged with a high-fat diet to induce obesity, Ctrp1 KO mice had increased physical activity and reduced body weight, adiposity, and expression of lipid synthesis and fibrotic genes in adipose tissue; these phenotypes were linked to elevated FGF-21 levels. Due in part to increased hepatic AMP-activated protein kinase activation and reduced expression of lipid synthesis genes, Ctrp1 KO mice fed a high-fat diet also had reduced liver and serum triglyceride and cholesterol levels. Taken together, these results provide genetic evidence to establish the significance of CTRP1 to systemic energy metabolism in different metabolic and dietary contexts.