Pathophysiology of sex hormone binding globulin (SHBG): relation to insulin

A Retrospective Review on Dysregulated Autophagy in Polycystic Ovary Syndrome: From Pathogenesis to Therapeutic Strategies

The main purpose of this article is to explore the relationship between autophagy and the pathological mechanism of PCOS, and to find potential therapeutic methods that can alleviate the pathological mechanism of PCOS by targeting autophagy. Relevant literatures were searched in the following databases, including: PubMed, MEDLINE, Web of Science, Scopus. The search terms were "autophagy", "PCOS", "polycystic ovary syndrome", "ovulation", "hyperandrogenemia", "insulin resistance", "inflammatory state", "circadian rhythm" and "treatment", which were combined according to the retrieval methods of different databases. Through analysis, we uncovered that abnormal levels of autophagy were closely related to abnormal ovulation, insulin resistance, hyperandrogenemia, and low-grade inflammation in patients with PCOS. Lifestyle intervention, melatonin, vitamin D, and probiotics, etc. were able to improve the pathological mechanism of PCOS via targeting autophagy. In conclusion, autophagy disorder is a key pathological mechanism in PCOS and is also a potential target for drug development and design.

The interplay of obesity, microbiome dynamics, and innovative anti-obesity strategies in the context of endometrial cancer progression and therapeutic approaches

Endometrial cancer (EC) is the most common gynecologic malignancy in the United States, and its incidence and mortality are rising. Obesity is more tightly associated with EC than any other cancer. Thus, the rising prevalence of obesity and associated risk factors, including diabetes and insulin resistance, cause alarm. The metabolic derangements of obesity increase the bioavailability of estrogen, hyperinsulinemia, and inflammation in a complex system with direct and indirect effects on the endometrium, resulting in proliferation and, ultimately, carcinogenesis. In addition, the gut dysbiosis associated with obesity helps contribute to these metabolic derangements, priming an individual for developing EC and perhaps affecting treatment efficacy. More recent studies are beginning to explore obesity's effect on the local tumor microbiome of EC and its role in carcinogenesis. Significant and sustained weight loss in individuals can considerably decrease the risk of EC, likely through reversal of the altered metabolism and dysbiosis resulting obesity. Bariatric surgery is the gold standard for successful weight loss and highlights how reversing of the systemic effects of obesity can reduce EC risk. However, the current limited availability, knowledge, and imposed stigma of bariatric surgery prohibits population-level reductions in EC. Therefore, effective and maintainable non-surgical dietary and pharmacologic interventions are needed.

Connecting the dots in the associations between diet, obesity, cancer, and microRNAs

The prevalence of obesity has reached pandemic levels worldwide, leading to a lower quality of life and higher health costs. Obesity is a major risk factor for noncommunicable diseases, including cancer, although obesity is one of the major preventable causes of cancer. Lifestyle factors, such as dietary quality and patterns, are also closely related to the onset and development of obesity and cancer. However, the mechanisms underlying the complex association between diet, obesity, and cancer remain unclear. In the past few decades, microRNAs (miRNAs), a class of small non-coding RNAs, have been demonstrated to play critical roles in biological processes such as cell differentiation, proliferation, and metabolism, highlighting their importance in disease development and suppression and as therapeutic targets. miRNA expression levels can be modulated by diet and are involved in cancer and obesity-related diseases. Circulating miRNAs can also mediate cell-to-cell communications. These multiple aspects of miRNAs present challenges in understanding and integrating their mechanism of action. Here, we introduce a general consideration of the associations between diet, obesity, and cancer and review the current knowledge of the molecular functions of miRNA in each context. A comprehensive understanding of the interplay between diet, obesity, and cancer could be valuable for the development of effective preventive and therapeutic strategies in future.

Effect of Selenium Supplementation on Biochemical Markers of Women with Polycystic Ovarian Syndrome: A Systematic Review

Polycystic ovary syndrome (PCOS) is a widespread endocrine disorder among fertile women and may be induced by nutritional deficiencies. In this study, we assess the impact of selenium supplementation (SS) on biochemical markers in women with PCOS. To gather relevant literature, we searched the Web of Science, Cochrane Library, Scopus, Embase, and MEDLINE databases from inception up to July 24, 2022. Subsequently, we included all published full-text randomized clinical trials examining the effects of SS versus placebo on biochemical changes in women with PCOS. Review Manager 5.3 was used to collect and analyze data and assess the risk of bias. Seven articles, comprising 413 women, were ultimately involved in the study. According to the results, SS could increase the level of quantitative insulin sensitivity check index [standardized mean difference (SMD)=0.34, 95% confidence interval (CI)=0.04∼0.65], total antioxidant capacity (SMD=0.89 mmol/L, 95% CI=0.52∼1.26), and glutathione (SMD=1.00 μmol/L, 95% CI=0.22∼1.78). Conversely, SS could decrease triglyceride, cholesterol, fasting plasma glucose, insulin, and the homeostasis model of assessment-insulin resistance levels compared with the placebo. Furthermore, there were no significant differences regarding sex hormone-binding globulin level, testosterone level, malondialdehyde, and body mass index between the two groups. In addition, the results suggest that SS improves biochemical markers in women with PCOS and thus is recommended for treating biochemical disorders among these women in addition to standard treatment.

Inflammation and Gastric Cancer

Gastric cancer remains a major killer globally, although its incidence has declined over the past century. It is the fifth most common cancer and the third most common reason for cancer-related deaths worldwide. Gastric cancer is the outcome of a complex interaction between environmental, host genetic, and microbial factors. There is significant evidence supporting the association between chronic inflammation and the onset of cancer. This association is particularly robust for gastrointestinal cancers in which microbial pathogens are responsible for the chronic inflammation that can be a triggering factor for the onset of those cancers. Helicobacter pylori is the most prominent example since it is the most widespread infection, affecting nearly half of the world’s population. It is well-known to be responsible for inducing chronic gastric inflammation progressing to atrophy, metaplasia, dysplasia, and eventually, gastric cancer. This review provides an overview of the association of the factors playing a role in chronic inflammation; the bacterial characteristics which are responsible for the colonization, persistence in the stomach, and triggering of inflammation; the microbiome involved in the chronic inflammation process; and the host factors that have a role in determining whether gastritis progresses to gastric cancer. Understanding these interconnections may improve our ability to prevent gastric cancer development and enhance our understanding of existing cases.

Sex hormone binding globulin as a potential drug candidate for liver-related metabolic disorders treatment

Sex hormone binding globulin (SHBG) is a hepatokine that binds to circulating steroid hormones (testosterone, oestradiol) to regulate their concentration in the bloodstream. Recently SHBG was recognized as an essential biomarker for metabolic syndrome (MetS) and hepatic steatosis development. At the hepatic level, the production of SHBG is mainly regulated by sex steroids and thyroxine. Studies of various research groups, including ours, showed that SHBG could be considered a reliable marker of insulin resistance and, therefore, can serve as a predictor of type 2 diabetes. Moreover, increased levels of circulating pro-inflammatory mediators strongly correlate with lowered serum levels of SHBG. This review paper emphasizes the role of SHBG as a potential drug candidate in the course of various metabolic dysfunctions, including non-alcoholic fatty liver disease (NAFLD), obesity, diabetes mellitus and insulin resistance. The studies related to SHBG and its role in the course of metabolic disorders are very limited. Here, we have summarized the most current knowledge about SHBG and its mechanism of action, indicating a novel concept for its possible therapeutic application in the management framework of commonly occurring metabolic dysfunctions.

Effect of Intermittent Fasting on Reproductive Hormone Levels in Females and Males: A Review of Human Trials

Intermittent fasting is a popular diet for weight loss, but concerns have been raised regarding the effects of fasting on the reproductive health of women and men. Accordingly, we conducted this literature review to clarify the effects of fasting on reproductive hormone levels in humans. Our results suggest that intermittent fasting decreases androgen markers (i.e., testosterone and the free androgen index (FAI)) while increasing sex hormone-binding globulin (SHBG) levels in premenopausal females with obesity. This effect was more likely to occur when food consumption was confined to earlier in the day (eating all food before 4 pm). In contrast, fasting did not have any effect on estrogen, gonadotropins, or prolactin levels in women. As for men, intermittent fasting reduced testosterone levels in lean, physically active, young males, but it did not affect SHBG concentrations. Interestingly, muscle mass and muscular strength were not negatively affected by these reductions in testosterone. In interpreting these findings, it is important to note that very few studies have been conducted on this topic. Thus, it is difficult to draw solid conclusions at present. From the limited data presented here, it is possible that intermittent fasting may decrease androgen markers in both genders. If this is the case, these results would have varied health implications. On the one hand, fasting may prove to be a valuable tool for treating hyperandrogenism in females with polycystic ovarian syndrome (PCOS) by improving menstruation and fertility. On the other hand, fasting may be shown to decrease androgens among males, which could negatively affect metabolic health and libido. More research is warranted to confirm these preliminary findings.

Efficacy of Myo-inositol on Anthropometric, Metabolic, and Endocrine Outcomes in PCOS Patients: a Meta-analysis of Randomized Controlled Trial

Polycystic ovary syndrome (PCOS) is a common cause of female infertility, affecting 5-10% of women of reproductive age. Many studies have reported improvement in insulin resistance and thereby intracellular glucose uptake after myo-inositol treatment in PCOS patients, but these studies have a small sample size, varying methodology, and outcome analysis. Therefore, we designed a present meta-analysis of randomized controlled trials to explore the effect of myo-inositol supplementation on anthropometric, metabolic, and endocrine outcomes in PCOS patients. Randomized controlled trials assessing the effectiveness of myo-inositol were identified in electronic databases like PubMed, Cochrane, Embase, MEDLINE, CINAHL, and AMED. Listed references and citations of related articles were also screened manually to identify additional studies. Research papers for which full-text copies were not available on scientific databases were procured from respective authors. Thereafter, data were extracted from included studies and analyzed using RevMan 5.3 of the Cochrane Collaboration. A total of 17 randomized controlled trials with 1083 PCOS patients were included in this meta-analysis. Among the 17 trials, 7 trials compared myo-inositol with folic acid, 8 trials compared myo-inositol with metformin, and 2 trials compared myo-inositol with oral contraceptives. No significant improvement in body mass index, waist-to-hip ratio, fasting insulin, fasting glucose, HOMA, LH, FSH, estradiol, sex hormone-binding globulin, dehydroepiandrosterone, and total testosterone levels were observed after myo-inositol treatment in PCOS patients except androstenedione and prolactin levels. Clinically significant improvement was not observed in anthropometric, metabolic, and endocrine outcomes after myo-inositol treatment in PCOS patients. However, heterogeneity between studies was high.

Could SARS-CoV-2 infection affect male fertility and sexuality?

Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) is the cause of coronavirus infectious disease (COVID‐19) and has rapidly spread worldwide, causing serious problems to the healthcare systems of many countries and hundreds of thousand deaths. In this review we discuss data from the literature to understand whether the various districts of the male reproductive system may represent another vulnerable target for SARS‐CoV‐2. Studies were searched from electronic databases such as Google Scholar, PubMed, Scopus, and COVID‐19 specific databases such as LitCovid, until July 31, 2021. It appears that SARS‐CoV‐2 virus infection not only causes damage to the respiratory system, but could have a serious impact on the reproductive system of male patients modulating many physiological processes. Like some other infections, SARS‐CoV‐2 also leads to a worsening of semen quality and an increase in oxidative stress (OS) levels. However, due to the limited number of studies, it is unclear whether this deterioration in semen parameters is temporary or lasts over time. It is certainly important that patients' reproductive function is monitored after coronavirus infection to avoid problems in reproductive health in the future.

Intermittent fasting in the prevention and treatment of cancer

Chronic caloric restriction (CR) has powerful anticarcinogenic actions in both preclinical and clinical studies but may be difficult to sustain. As an alternative to CR, there has been growing interest in intermittent fasting (IF) in both the scientific and lay community as a result of promising study results, mainly in experimental animal models. According to a survey by the International Food Information Council Foundation, IF has become the most popular diet in the last year, and patients with cancer are seeking advice from oncologists about its beneficial effects for cancer prevention and treatment. However, as discussed in this review, results from IF studies in rodents are controversial and suggest potential detrimental effects in certain oncologic conditions. The effects of IF on human cancer incidence and prognosis remain unknown because of a lack of high-quality randomized clinical trials. Preliminary studies suggest that prolonged fasting in some patients who have cancer is safe and potentially capable of decreasing chemotherapy-related toxicity and tumor growth. However, because additional trials are needed to elucidate the risks and benefits of fasting for patients with cancer, the authors would not currently recommend patients undergoing active cancer treatment partake in IF outside the context of a clinical trial. IF may be considered in adults seeking cancer-prevention benefits through means of weight management, but whether IF itself affects cancer-related metabolic and molecular pathways remains unanswered.

Homozygous SHBG Variant (rs6258) Linked to Gonadotropin-Independent Precocious Puberty in a Young Girl

Sex hormone-binding globulin (SHBG) in the blood is a major determinant of bioactivity for key sex steroids such as testosterone and estradiol. Low serum levels of SHBG have been associated with obesity, polycystic ovaries, and metabolic syndrome, and other states associated with hyperandrogenemia. A 9-year, 6-month-old girl presented with a history of peripheral precocious puberty and aggressive behavior. The patient's SHBG level was remarkably low for her age, at less than 5 nmol/L (reference range for a girl with a bone age of 10 years, 73 nmol/L [SEM = 10]) [1]. On genetic and protein analysis, the patient was found to have a homozygous missense potentially pathogenic variant in the SHBG gene (c.554C>T, p.P185L); her parents were asymptomatic heterozygote carriers. Laboratory investigations supported the possible involvement of this genetic alteration in the patient's phenotype. Various analyses of this variant support its pathogenicity, although the exact mechanism remains unclear. In conclusion, we present a genetic SHBG variant in the homozygote state that may have been associated with gonadotropin-independent precocious puberty in a young girl.

Intermittent and Periodic Fasting, Hormones, and Cancer Prevention

The restriction of proteins, amino acids or sugars can have profound effects on the levels of hormones and factors including growth hormone, IGF-1 and insulin. In turn, these can regulate intracellular signaling pathways as well as cellular damage and aging, but also multisystem regeneration. Both intermittent (IF) and periodic fasting (PF) have been shown to have both acute and long-term effects on these hormones. Here, we review the effects of nutrients and fasting on hormones and genes established to affect aging and cancer. We describe the link between dietary interventions and genetic pathways affecting the levels of these hormones and focus on the mechanisms responsible for the cancer preventive effects. We propose that IF and PF can reduce tumor incidence both by delaying aging and preventing DNA damage and immunosenescence and also by killing damaged, pre-cancerous and cancer cells.

Sex steroid hormones are associated with mortality in COVID-19 patients: Level of sex hormones in severe COVID-19

In patients with coronavirus disease 2019 (COVID-19), men are more severely affected than women. Multiple studies suggest that androgens might play a role in this difference in disease severity. Our objective was to assess the association between sex hormone levels and mortality in patients with severe COVID-19.We selected patients from the Amsterdam University Medical Centers COVID-19 Biobank, in which patients admitted to hospital in March and April 2020, with reverse transcription-polymerase chain reaction proven severe acute respiratory syndrome-coronavirus-2 infection, were prospectively included. Specifically, we included postmenopausal women (>55 years) and age-matched men, with a mortality of 50% in each group. Residual plasma samples were used to measure testosterone, estradiol, sex hormone binding globulin (SHBG), and albumin. We investigated the association of the levels of these hormones with mortality in men and women.We included 16 women and 24 men in March and April 2020 of whom 7 (44%) and 13 (54%), respectively, died. Median age was 69 years (interquartile range [IQR] 64-75). In men, both total and free testosterone was significantly lower in deceased patients (median testosterone 0.8 nmol/L [IQR 0.4-1.9] in deceased patients vs 3.2 nmol/L [IQR 2.1-7.5] in survivors; P < .001, and median free testosterone 33.2 pmol/L [IQR 15.3-52.2] in deceased patients vs 90.3 pmol/L [IQR 49.1-209.7] in survivors; P = .002). SHBG levels were significantly lower in both men and women who died (18.5 nmol/L [IQR 11.3-24.3] in deceased patients vs 34.0 nmol/L [IQR 25.0-48.0] in survivors; P < .001). No difference in estradiol levels was found between deceased and surviving patients.Low SHBG levels were associated with mortality rate in patients with COVID-19, and low total and free testosterone levels were associated with mortality in men. The role of testosterone and SHBG and potential of hormone replacement therapy needs further exploration in COVID-19.

Ovarian conservation for young women with early-stage, low-grade endometrial cancer: a 2-step schema

In 2020, endometrial cancer continues to be the most common gynecologic malignancy in the United States. The majority of endometrial cancer is low grade, and nearly 1 of every 8 low-grade endometrial cancer diagnoses occurs in women younger than 50 years with early-stage disease. The incidence of early-stage, low-grade endometrial cancer is increasing particularly among women in their 30s. Women with early-stage, low-grade endometrial cancer generally have a favorable prognosis, and hysterectomy-based surgical treatment alone can often be curative. In young women with endometrial cancer, consideration of ovarian conservation is especially relevant to avoid both the short-term and long-term sequelae of surgical menopause including menopausal symptoms, cardiovascular disease, metabolic disease, and osteoporosis. Although disadvantages of ovarian conservation include failure to remove ovarian micrometastasis (0.4%-0.8%), gross ovarian metastatic disease (4.2%), or synchronous ovarian cancer (3%-5%) at the time of surgery and the risk of future potential metachronous ovarian cancer (1.2%), ovarian conservation is not negatively associated with endometrial cancer-related or all-cause mortality in young women with early-stage, low-grade endometrial cancer. Despite this, utilization of ovarian conservation for young women with early-stage, low-grade endometrial cancer remains modest with only a gradual increase in uptake in the United States. We propose a framework and strategic approach to identify young women with early-stage, low-grade endometrial cancer who may be candidates for ovarian conservation. This evidence-based schema consists of a 2-step assessment at both the preoperative and intraoperative stages that can be universally integrated into practice.

Total testosterone is not associated with lean mass or handgrip strength in pre-menopausal females

The aim of this study was to examine the relationship between endogenous testosterone concentrations and lean mass and handgrip strength in healthy, pre-menopausal females. Testosterone has been positively associated with lean mass and strength in young and older males. Whether this relationship exists in pre-menopausal females is unknown. Secondary data from the 2013-2014 National Health and Nutrition Examination Survey were used to test this relationship. Females were aged 18-40 (n = 716, age 30 ± 6 years, mean ± SD) and pre-menopausal. Multivariate linear regression models were used to examine associations between total testosterone, lean mass index (LMI) and handgrip strength. Mean ± SD testosterone concentration was 1.0 ± 0.6 nmol L-1 and mean free androgen index (FAI) was 0.02 ± 0.02. In pre-menopausal females, testosterone was not associated with LMI (β = 0.05; 95%CI - 0.04, 0.15; p = 0.237) or handgrip strength (β = 0.01; 95%CI - 0.11, 0.12; p = 0.926) in a statistically significant manner. Conversely, FAI was associated with LMI (β = - 0.03; 95%CI - 0.05, - 0.02; p = 0.000) in a quadratic manner, meaning LMI increases with increasing FAI levels. Handgrip strength was not associated with FAI (β = 0.06; 95%CI - 0.02, 0.15; p = 0.137). These findings indicate that FAI, but not total testosterone, is associated with LMI in pre-menopausal females. Neither FAI nor total testosterone are associated with handgrip strength in pre-menopausal females when testosterone concentrations are not altered pharmacologically.

Diversity of insulin and IGF signaling in breast cancer: Implications for therapy

This review highlights the significance of the insulin receptor (IR) and insulin-like growth factor-1 receptor (IGF-1R) signaling pathway in cancer and assesses its potential as a therapeutic target. Our emphasis is on breast cancer, but this pathway is central to the behavior of many cancers. An understanding of how IR/IGF-1R signaling contributes to the function of the normal mammary gland provides a foundation for understanding its aberrations in breast cancer. Specifically, dysregulation of the expression and function of ligands (insulin, IGF-1 and IGF-2), receptors and their downstream signaling effectors drive breast cancer initiation and progression, often in a subtype-dependent manner. Efforts to target this pathway for the treatment of cancer have been hindered by several factors including a lack of biomarkers to select patients that could respond to targeted therapy and adverse effects on normal metabolism. To this end, we discuss ongoing efforts aimed at overcoming such obstacles.

Emerging Protein Biomarkers for the Diagnosis or Prediction of Gestational Diabetes-A Scoping Review

Introduction: Gestational diabetes (GDM), defined as hyperglycemia with onset or initial recognition during pregnancy, has a rising prevalence paralleling the rise in type 2 diabetes (T2DM) and obesity. GDM is associated with short-term and long-term consequences for both mother and child. Therefore, it is crucial we efficiently identify all cases and initiate early treatment, reducing fetal exposure to hyperglycemia and reducing GDM-related adverse pregnancy outcomes. For this reason, GDM screening is recommended as part of routine pregnancy care. The current screening method, the oral glucose tolerance test (OGTT), is a lengthy, cumbersome and inconvenient test with poor reproducibility. Newer biomarkers that do not necessitate a fasting sample are needed for the prompt diagnosis of GDM. The aim of this scoping review is to highlight and describe emerging protein biomarkers that fulfill these requirements for the diagnosis of GDM. Materials and Methods: This scoping review was conducted according to preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines for scoping reviews using Cochrane Central Register of Controlled Trials (CENTRAL), the Cumulative Index to Nursing & Allied Health Literature (CINAHL), PubMed, Embase and Web of Science with a double screening and extraction process. The search included all articles published in the literature to July 2020. Results: Of the 3519 original database citations identified, 385 were eligible for full-text review. Of these, 332 (86.2%) were included in the scoping review providing a total of 589 biomarkers studied in relation to GDM diagnosis. Given the high number of biomarkers identified, three post hoc criteria were introduced to reduce the items set for discussion: we chose only protein biomarkers with at least five citations in the articles identified by our search and published in the years 2017-2020. When applied, these criteria identified a total of 15 biomarkers, which went forward for review and discussion. Conclusions: This review details protein biomarkers that have been studied to find a suitable test for GDM diagnosis with the potential to replace the OGTT used in current GDM screening protocols. Ongoing research efforts will continue to identify more accurate and practical biomarkers to take GDM screening and diagnosis into the 21st century.

The hepatic lipidome and HNF4α and SHBG expression in human liver

Low plasma levels of sex hormone-binding globulin (SHBG) are a marker for obesity, insulin resistance, non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes. The transcription factor HNF4α is a major determinant of hepatic SHBG expression and thereby serum SHBG levels, and mediates in part the association of low SHBG with hyperinsulinemia and hepatic steatosis. We analyzed the lipidome in human liver specimens from a cohort of patients who underwent hepatic resection as a treatment for cancer, providing insight into hepatic lipids in those without extreme obesity or the clinical diagnosis of NAFLD or non-alcoholic steatohepatitis. Both steatosis and high HOMA-IR were associated with higher levels of saturated and unsaturated FA, other than arachidonic, with the most dramatic rise in 18:1 oleate, consistent with increased stearoyl-CoA desaturase activity. Individuals with low HOMA-IR had low levels of total hepatic fatty acids, while both low and high fatty acid levels characterized the high HOMA-IR group. Both insulin resistance and high levels of hepatic fat were associated with low expression levels of HNF4α and thereby SHBG, but the expression of these genes was also low in the absence of these determinants, implying additional regulatory mechanisms that remain to be determined. The relationship of all FA studied to HNFα and SHBG mRNAs was inverse, and similar to that for total triglyceride concentrations, irrespective of chain length and saturation vs unsaturation.

Cancer Risk After Bariatric Surgery in a Cohort Study from the Five Nordic Countries

PURPOSE

Obesity increases the risk of several cancers, but the influence of bariatric surgery on the risk of individual obesity-related cancers is unclear. This study aimed to assess the impact of bariatric surgery on cancer risk in a multi-national setting.

MATERIALS AND METHODS

This cohort study included all adults with an obesity diagnosis identified from national patient registries in all Nordic countries (Denmark, Finland, Iceland, Norway and Sweden) from 1980 to 2012. Cancer risk in bariatric surgery patients was compared with non-operated patients with obesity. Multivariable Cox regression provided adjusted hazard ratios (HRs) with 95% confidence intervals (CIs). Age, sex, calendar year, country, length of follow-up, diabetes, chronic obstructive pulmonary disease and alcohol-related diseases were evaluated as confounders.

RESULTS

Among 482,572 participants with obesity, 49,096 underwent bariatric surgery. Bariatric surgery was followed by a decreased overall cancer risk in women (HR 0.86, 95% CI 0.80-0.92), but not in men (HR 0.98, 95% CI 0.95-1.01). The risk reduction was observed only within the first five post-operative years. Among specific tumours, HRs decreased for breast cancer (HR 0.81, 95% CI 0.69-0.95), endometrial cancer (HR 0.69, 95% CI 0.56-0.84) and non-Hodgkin lymphoma (HR 0.64, 95% CI 0.42-0.97) in female bariatric surgery patients, while the risk of kidney cancer increased in both sexes (HR 1.44, 95% CI 1.13-1.84).

CONCLUSION

Bariatric surgery may decrease overall cancer risk in women within the first five years after surgery. This decrease may be explained by a decreased risk of breast and endometrial cancer and non-Hodgkin lymphoma in women.

The effect of synbiotic on glycemic profile and sex hormones in overweight and obese breast cancer survivors following a weight-loss diet: A randomized, triple-blind, controlled trial

BACKGROUND

The investigation was designed to assess the effects of synbiotic supplementation on glycemic profile, insulin-like growth factor-1 (IGF-1) and sex hormones in overweight and obese postmenopausal breast cancer survivors (BCSs) who had hormone-receptor-positive breast cancer.

METHODS

This randomized, triple-blind, placebo-controlled trial was conducted on 76 overweight and obese BCSs aged 57.43 (5.82) years. All participants were given a specified low calorie diet and were randomly assigned into two groups to intake 10⁹ CFU/day of synbiotic supplement (n = 38) or placebo (n = 38) for 8 weeks. Body composition, physical activity, glycemic profile, IGF-1, estradiol, testosterone and dehydroepiandrosterone sulfate (DHEA-S) were measured at baseline and after 8 weeks.

RESULTS

A significant reduction in serum insulin (median change (Q1, Q3) from baseline of -1.05 (-2.36, 0.32) μIU/mL; P = 0.006) and insulin resistance (HOMA-IR) (mean change (SD) from baseline of -4.0 (0.9); P = 0.007) were seen over the 8 weeks in the synbiotic group. However, no significant changes were observed in serum insulin, fasting plasma glucose, HbA1c, HOMA-IR, IGF-1, estradiol, testosterone, DHEA-S and sex hormone binding globulin between-groups at the end of the intervention.

CONCLUSIONS

Overall, as the 8-week synbiotic consumption compared with placebo had insignificant-reducing effects on glycemic profile, IGF-1 and sex hormones among overweight and obese postmenopausal BCSs, synbiotics may exert considerable beneficial consequences, which need to be further assessed in future clinical trials.

TRIAL REGISTRATION

IRCT, IRCT2015090223861N1. Registered 02 February 2017, http://www.irct.ir: IRCT2015090223861N1.

Obesity and the Risk of Gastrointestinal Cancers

Obesity is a risk factor for all major gastrointestinal cancers. With the rapid increase in the prevalence of obesity worldwide, this link could lead to an elevated burden of cancers of the digestive system. Currently, three main mechanisms explaining the link between excess adiposity and gastrointestinal cancer risk are being considered, including altered insulin signaling, obesity-associated chronic low-grade inflammation, and altered sex hormone metabolism, although new potential mechanisms emerge. This review is aimed to present our current knowledge on biological mechanisms involved in adiposity-related gastrointestinal carcinogenesis supported by results collected in epidemiological studies.

Effects of Metformin on Cellular Proliferation and Steroid Hormone Receptors in Patient-Derived, Low-Grade Endometrial Cancer Cell Lines

Endometrial cancer (EC) is the most common gynecologic malignancy and is the result of disruption of the balance between estrogen-stimulated growth and progesterone-induced growth modulation. Metformin has been shown to inhibit EC proliferation; however, its role in early-stage EC and its effects on steroid hormone receptors have not been adequately explored. Our aim was to examine the effects of metformin on cellular proliferation in patient-derived, low-grade EC cell lines and to determine whether it directly modulates steroid hormone receptor expression. Two novel EC cell lines were produced (EM2 and 3) from endometrial tumor tissue obtained from women undergoing surgery. Cellular proliferation was determined by the 3-(4,5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide assay, and in both cell lines, metformin decreased cell proliferation in a dose-dependent (10-200 µmol/L) manner and induced apoptosis as measured by cleaved PARP. Furthermore, metformin abrogated the effects of E2 on cell proliferation. Using quantitative real-time polymerase chain reaction and Western immunoblotting, metformin significantly decreased estrogen receptor (ER) α messenger RNA abundance but did not consistently affect the expression of progesterone receptor. Estrogen receptor α protein levels significantly decreased across all metformin doses tested, which resulted in a significant decrease in the expression of the ER targets genes Keratin-19 and Wnt-1 inducible signaling pathway 2. In addition, metformin increased phosphorylation of AMPK in a dose-dependent manner (10-200 µmol/L) indicating an effect on mammalian target of rapamycin (mTOR) signaling. Our data suggest that metformin therapy represents a potential fertility-sparing option for women with early-stage EC, given its capacity to inhibit EC cell proliferation, ERα expression, and the mTOR cell proliferation pathway.

Testosterone a key factor in gender related metabolic syndrome

Metabolic syndrome (MetS) is highly correlated with cardiovascular diseases. Although an excess of body fat is a determinant factor for MetS development, a reduced level of testosterone plays a fundamental role in its regulation. Low testosterone level is highly related to insulin resistance, visceral obesity and MetS. We have searched in Pubmed clinical trial with the password: testosterone and insulin resistance, and testosterone and MetS. We found 19 studies on the correlation between testosterone level with insulin resistance and 18 on the effect of testosterone therapy on MetS. A high correlation between low testosterone and insulin resistance has been found in men, but not in women. Testosterone administration in hypogonadal men improved MetS and reduced the mortality risk. Androgen and oestrogen receptors are expressed in adipocytes, muscle and liver tissue, and their activation is necessary to improve metabolic control. Normalization of testosterone level should be the primary treatment in men, along with caloric restriction and physical exercise. These findings come mainly from correlative data, and there remains a need for randomized trials to strengthen this evidence. This review will consider the effects of testosterone on the regulation and development of MetS in men and women.

MANAGEMENT OF ENDOCRINE DISEASE Hyperandrogenic states in women: pitfalls in laboratory diagnosis

Measuring total testosterone level is the first-line approach in assessing androgen excess in women. The main pitfalls in measuring testosterone relate to its low concentration and to the structural similarity between circulating androgens and testosterone, requiring accurate techniques with high specificity and sensitivity. These goals can be achieved by immunoassay using a specific anti-testosterone monoclonal antibody, ideally after an extraction step. Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) will be commonly used for measuring testosterone, providing optimal accuracy with a low limit of detection. Yet, the pitfalls of these two techniques are well identified and must be recognized and systematically addressed. In general, laboratories using direct testosterone immunoassay and mass spectrometry need to operate within a quality framework and be actively engaged in external quality control processes and standardization, so as to ensure appropriate interpretation irrespective of the particular laboratory. Circulating testosterone is strongly bound to sex-hormone-binding globulin (SHBG), and SHBG levels are typically low in overweight hyperandrogenic patients. Thus, low SHBG may decrease circulating testosterone to normal values, which will mask androgen excess status. One way to avoid this pitfall, awaiting direct free testosterone assays that are yet to be developed, is to measure SHBG and calculate free testosterone. A few other pitfalls will be discussed in this review, including those of adrenal androgen exploration, with the aim of helping clinicians to better handle laboratory investigation of androgen excess disorders in women.

Current perspectives between metabolic syndrome and cancer

Metabolic syndrome is a cluster of risk factors that lead to cardiovascular morbidity and mortality. Recent studies linked metabolic syndrome and several types of cancer. Although metabolic syndrome may not necessarily cause cancer, it is linked to poorer cancer outcomes including increased risk of recurrence and overall mortality. This review tends to discuss the major biological and physiological alterations involved in the increase of incidence and mortality of cancer patients affected by metabolic syndrome. We focus on metabolic syndrome-associated visceral adiposity, hyperinsulinemia, hyperglycemia, insulin-like growth factor (IGF-I) pathway as well as estrogen signaling and inflammation. Several of these factors are also involved in carcinogenesis and cancer progression. A better understanding of the link between metabolic syndrome and cancer may provide new insight about oncogenesis. Moreover, prevention of metabolic syndrome - related alterations may be an important aspect in the management of cancer patients during simultaneous palliative care.

Chinese Herbal Medicine for the Optimal Management of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a complex heterogeneous disorder characterized by androgen excess and ovulatory dysfunction; it is now known to be closely linked to metabolic syndrome. Recent research suggests that insulin resistance plays an important role in the pathogenesis of PCOS which may lead to the excessive production of androgens by ovarian theca cells. Currently there is no single drug that can treat both the reproductive and metabolic complications of the disorder. Existing pharmaceutical agents such as hormonal therapies have been associated with side effects and are not appropriate for PCOS women with infertility. Additionally, insulin sensitizing agents useful for treating the metabolic abnormalities in PCOS have limited efficacy for treating reproductive aspects of the disorder. Chinese herbal medicines have a long history of treating gynaecological problems and infertility and therefore may be a novel approach to the treatment of PCOS. Current research demonstrates that the compounds isolated from herbs have shown beneficial effects for PCOS and when combined in an herbal formula can target both reproductive and metabolic defects simultaneously. Therefore, further investigation into Chinese herbal medicine in the treatment of PCOS is warranted.

The impact of obesity on hyperandrogenemia in Korean girls

PURPOSE

As metabolic complication and polycystic ovarian syndrome due to childhood obesity is rising, the role of hyperandrogenemia (HA) and hyperinsulinism is receiving attention. The aims of this study were to investigate the presence of obvious HA according to pubertal status and to find potential etiologic determinants of HA in Korean obese (OB) girls.

METHODS

We analyzed 91 girls aged 6-17 years (prepuberty, n=54; puberty, n=37). Each girl was classified as being either normal weight (NW) or OB. Anthropometric measurements were obtained and blood test was performed early in the morning after at least 8 hours of fasting to measure glucose, insulin, total testosterone, sex hormone-binding globulin, dehydroepiandrosterone sulfate (DHEAS), luteinizing hormone (LH), follicular-stimulating hormone, estradiol, and progesterone.

RESULTS

The plasma levels of free testosterone (FT) and DHEAS were markedly higher in OB girls compared to NW girls in puberty (FT, P=0.009; DHEAS, P=0.046) but not in prepuberty (FT, P=0.183; DHEAS, P=0.052). Hyperinsulinemia and high homeostasis model assessment of insulin resistance (HOMA-IR) values were found regardless of pubertal status in OB girls. The significant related factor to HA in puberty was the body mass index Z-score (P=0.003). But HOMA-IR, LH, and progesterone levels were not relevant to HA in pubertal girls.

CONCLUSION

OB prepubertal girls did not show HA in the present study but they should be regularly monitored because they already had hyperinsulinemia. OB pubertal girls had significant HA and hyperinsulinemia, and obesity per se was the most important factor for HA.

Diabetes Mellitus and Risk of Colorectal Cancer Mortality in Japan: the Japan Collaborative Cohort Study

Objective:

Our aim was to estimate whether diabetes mellitus (DM) may be associated with an increased risk of colorectal cancer (CRC) mortality in Japan.

Methods:

The Japan Collaborative Cohort (JACC) Study is a nationwide prospective study, initiated in 1988, which involves 110,585 subjects (age range: from 40 to 79 years; 46,395 males and 64,190 females). Our present analysis population comprised 96,081 (40,510 men and 55,571 women) who provided details on DM history. The questionnaire also included age, sex, weight, height, family history of CRC, smoking, drinking and exercise habits, and education. Cox proportional-hazard regression was used to estimate the hazard ratio (HR). We used SPSS 21 software to analyze all data.

Results:

Among the participants with DM, we followed up for 71,174 person-years and 640. deaths from CRC were confirmed; and, among the non-diabetic participants, 785 CRC deaths were identified during 1,499,324 person-years. After adjusting for multivariate confounding factors, such as age, sex, body mass index (BMI), family history of colorectal cancer, smoking habit, drinking habit, physical activity (sports and walking) and education, DM was associated with an increased risk of CRC death (HR 1.4, 95% confidence interval [CI] 1.0-2.0). Diabetic women, but not diabetic men, experienced increased mortality from CRC (HR 1.7, 95% CI 1.0-3.0).

Conclusion:

The risk of CRC mortality is significantly increased in both sexes and women with diabetes, but no significant increase was seen for diabetic men among Japanese.

Assessment of Multifactor Gene-Environment Interactions and Ovarian Cancer Risk: Candidate Genes, Obesity, and Hormone-Related Risk Factors

BACKGROUND

Many epithelial ovarian cancer (EOC) risk factors relate to hormone exposure and elevated estrogen levels are associated with obesity in postmenopausal women. Therefore, we hypothesized that gene-environment interactions related to hormone-related risk factors could differ between obese and non-obese women.

METHODS

We considered interactions between 11,441 SNPs within 80 candidate genes related to hormone biosynthesis and metabolism and insulin-like growth factors with six hormone-related factors (oral contraceptive use, parity, endometriosis, tubal ligation, hormone replacement therapy, and estrogen use) and assessed whether these interactions differed between obese and non-obese women. Interactions were assessed using logistic regression models and data from 14 case-control studies (6,247 cases; 10,379 controls). Histotype-specific analyses were also completed.

RESULTS

SNPs in the following candidate genes showed notable interaction: IGF1R (rs41497346, estrogen plus progesterone hormone therapy, histology = all, P = 4.9 × 10(-6)) and ESR1 (rs12661437, endometriosis, histology = all, P = 1.5 × 10(-5)). The most notable obesity-gene-hormone risk factor interaction was within INSR (rs113759408, parity, histology = endometrioid, P = 8.8 × 10(-6)).

CONCLUSIONS

We have demonstrated the feasibility of assessing multifactor interactions in large genetic epidemiology studies. Follow-up studies are necessary to assess the robustness of our findings for ESR1, CYP11A1, IGF1R, CYP11B1, INSR, and IGFBP2 Future work is needed to develop powerful statistical methods able to detect these complex interactions.

IMPACT

Assessment of multifactor interaction is feasible, and, here, suggests that the relationship between genetic variants within candidate genes and hormone-related risk factors may vary EOC susceptibility. Cancer Epidemiol Biomarkers Prev; 25(5); 780-90. ©2016 AACR.

Sex Hormone-Binding Globulin in Children and Adolescents

Sex hormone-binding globulin (SHBG) is a circulating glycoprotein that transports testosterone and other steroids in the blood. Interest in SHBG has escalated in recent years because of its inverse association with obesity and insulin resistance, and because many studies have linked lower circulating levels of SHBG to metabolic syndrome, type 2 diabetes, nonalcoholic fatty liver disease, polycystic ovary syndrome, and early puberty. The purpose of this review is to summarize molecular, clinical, endocrine, and epidemiological findings to illustrate how measurement of plasma SHBG may be useful in clinical medicine in children.

Effects of selenium supplementation on glucose homeostasis and free androgen index in women with polycystic ovary syndrome: A randomized, double blinded, placebo controlled clinical trial

BACKGROUND/OBJECTIVES

Insulin resistance (IR) is a main pathophysiologic feature in polycystic ovary syndrome (PCOS) patients which is triggered by elevated oxidative stress in these patients. Selenium, an essential micronutrient, is a major constituent of antioxidant enzymes such as glutathione peroxidase. Recently, decreased plasma selenium concentrations were reported in PCOS patients. So, the present study was carried out in order to assess whether selenium consumption can improve the metabolic response to insulin and reduce the insulin resistance in these women.

SUBJECTS/METHODS

A total of 53 PCOS patients (diagnosed by Rotterdam criteria), 18-42 years old, participated in this randomized, double-blind and placebo controlled trial for 12 weeks (selenium, n=26; placebo, n=27). The effects of daily administration of 200 μg selenium or placebo on serum glucose, total testosterone (tT), sex hormone binding globulin (SHBG) and free androgen index (FAI) in fasting state were evaluated.

RESULTS

At the end of the study, insulin resistance was significantly increased in selenium recipients when compared with the placebo group (2.05 ± 0.39 when compared with 1.81 ± 0.25, p=0.017). Also, selenium supplementation resulted in marginally significant increase (p=0.056) in insulin level when compared with the placebo group. There were no statistically significant changes in other study endpoints, when comparing the two groups.

CONCLUSION

This study showed that selenium supplementation in PCOS patients may worsen insulin resistance in them. Until the results of larger studies become available, indiscriminate consumption of selenium supplements in PCOS patients will warrant caution.

Sonographic markers of ovarian morphology, but not hirsutism indices, predict serum total testosterone in women with regular menstrual cycles

OBJECTIVE

To determine whether sonographic markers of ovarian morphology or male pattern hair growth scores predict androgen levels in women with regular or irregular menstrual cycles.

DESIGN

Cross-sectional observational study.

SETTING

Clinical research unit.

PATIENT(S)

Seventy-six women of reproductive age (18-39 years) were evaluated for male-pattern hair growth (using a modified Ferriman-Gallwey scoring system), ovarian morphology (by transvaginal ultrasonography), and total serum testosterone (T) (by liquid chromatography tandem mass spectrometry).

INTERVENTION(S)

Not applicable.

MAIN OUTCOME MEASURE(S)

Regional and total modified Ferriman-Gallwey scores, number of follicles per follicle size category, follicle number per ovary, ovarian volume, ovarian area, stromal to ovarian area ratio, stromal echogenicity index, total testosterone (total T), and menstrual cycle length.

RESULT(S)

Neither regional nor total modified Ferriman-Gallwey scores correlated with total T concentrations in women with regular or irregular menstrual cycles, as judged by the Least Absolute Shrinkage and Selection Operator technique. By contrast, a sonographic marker (follicle number per ovary 6-9 mm) significantly predicted total T concentrations in women with regular menstrual cycles but not in women with irregular menstrual cycles.

CONCLUSION(S)

Sonographic markers of ovarian morphology, but not hirsutism scores, predicted total T levels. However, the predictive value of ovarian morphology for total T differed by menstrual cycle status. That sonographic markers did not predict androgen levels in a diverse cohort of women with cycle irregularity suggests the potential for distinct variations in ovarian morphology for androgenic and nonandrogenic types of cycle irregularity. Overall, our findings support that an assessment of ovarian morphology may be helpful in reflecting total T levels.

Evidence of male hypogonadism at an early age as a familial risk of type 2 diabetes

OBJECTIVE

Previous investigations provide evidence of an association of hypogonadism with type 2 diabetes in men, and low testosterone levels have been regarded a risk factor for the disease. Since a strong genetic predisposition to type 2 diabetes has been demonstrated, here we investigate a possible tendency towards hypogonadism in young male offspring of diabetic parents.

MATERIAL AND METHODS

The study compares 32 male offspring of diabetic parents with 31 male offspring of nondiabetic parents matched by age. The subjects comprised boys (9-17 years) and young adults (19-25 years). Anthropomorphic measurements were made in all subjects. Fasting blood samples were analyzed for glucose and serum concentrations of testosterone (T), sex hormone-binding globulin (SHBG), luteinizing hormone (LH), insulin and leptin were measured by ELISA. Free testosterone (FT) was calculated using T and SHBG levels.

RESULTS

Serum T, FT and bioavailable T (BAT) levels in offspring of diabetic parents were significantly lower than those of offspring of nondiabetic parents across all age groups. Mean serum LH levels were also lower in offspring of diabetic parents compared to the controls. Although LH levels in young adults with diabetic parents, tended to be lower than those of age-matched controls but the difference was not statistically significant. Serum insulin and leptin, and insulin resistance measured by HOMA-IR were significantly raised in older offspring of diabetic parents but were within the normal range.

CONCLUSION

Whereas hypogonadism was the only indicator of a possible predisposition to metabolic dysfunction in peripubertal children of diabetic parents, a significant change in other metabolic markers becomes apparent at a more advanced age.

The Association of a Mediterranean-Style Diet Pattern with Polycystic Ovary Syndrome Status in a Community Cohort Study

Polycystic ovary syndrome (PCOS) is a common condition in reproductive-aged women. While lifestyle management is first-line treatment in PCOS, the dietary intake of women with PCOS is unclear and there is no research assessing dietary patterns of women with and without PCOS. The aim of this study was to examine dietary patterns in a large cohort of women with and without PCOS. Data were from 7569 participants in the 1973–1978 cohort of the Australian Longitudinal Study on Women’s Health population assessed at 2009 (Survey 5) (n = 414 PCOS, n = 7155 non-PCOS). Dietary patterns were evaluated using factor analysis and multiple logistic regressions assessed their associations with PCOS status. Three dietary patterns were identified that explained 27% of the variance in food intake between women with and without PCOS: Non-core foods; Meats and take-away and Mediterranean-style. The Mediterranean-style dietary pattern was independently associated with PCOS status. On adjusted analysis for each 1 SD increase in the Mediterranean-style dietary pattern, there was a 26% greater likelihood that women had PCOS. This may indicate an improvement in the quality of dietary intake following a diagnosis of PCOS. Future research should examine the contribution of dietary patterns to the incidence and severity of PCOS and the potential for modification of dietary patterns in the lifestyle management of PCOS.

Effects of exercise dose on endogenous estrogens in postmenopausal women: a randomized trial

Exercise dose comparison trials with biomarker outcomes can identify the amount of exercise required to reduce breast cancer risk and also strengthen the causal inference between physical activity and breast cancer. The Breast Cancer and Exercise Trial in Alberta (BETA) tested whether or not greater changes in estradiol (E2), estrone, and sex hormone-binding globulin (SHBG) concentrations can be achieved in postmenopausal women randomized to 12 months of HIGH (300 min/week) vs MODERATE (150 min/week) volumes of aerobic exercise. BETA included 400 inactive postmenopausal women aged 50-74 years with BMI of 22-40 kg/m(2). Blood was drawn at baseline and 6 and 12 months. Adiposity, physical fitness, diet, and total physical activity were assessed at baseline and 12 months. Intention-to-treat analyses were performed using linear mixed models. At full prescription, women exercised more in the HIGH vs MODERATE group (median min/week (quartiles 1,3): 253 (157 289) vs 137 (111 150); P<0.0001). Twelve-month changes in estrogens and SHBG were <10% on average for both groups. No group differences were found for E2, estrone, SHBG or free E2 changes (treatment effect ratios (95% CI) from linear mixed models: 1.00 (0.96-1.06), 1.02 (0.98-1.05), 0.99 (0.96-1.02), 1.01 (0.95, 1.06), respectively, representing the HIGH:MODERATE ratio of geometric mean biomarker levels over 12 months; n=382). In per-protocol analyses, borderline significantly greater decreases in total and free E2 occurred in the HIGH group. Overall, no dose effect was observed for women randomized to 300 vs 150 min/week of moderate to vigorous intensity exercise who actually performed a median of 253 vs 137 min/week. For total and free E2, the lack of differential effect may be due to modest adherence in the higher dose group.

The integrative role of leptin, oestrogen and the insulin family in obesity-associated breast cancer: potential effects of exercise

Obesity is an established risk factor for postmenopausal breast cancer. The mechanisms through which obesity influences the development and progression of breast cancer are not fully elucidated; however, several factors such as increased oestrogen, concentrations of various members of the insulin family and inflammation that are associated with adiposity are purported to be important factors in this relationship. Emerging research has also begun to focus on the role of adipokines, (i.e. adipocyte secreted factors), in breast cancer. Leptin secretion is directly related to adiposity and is believed to promote breast cancer directly and independently, as well as through involvement with the oestrogen and insulin signalling pathways. As leptin is secreted from white adipose tissue, any intervention that reduces adiposity may be favourable. However, it is also important to consider that energy expenditure through exercise, independent of fat loss, may improve leptin regulation. The purpose of this narrative review was to explore the role of leptin in breast cancer development and progression, identify key interactions with oestrogen and the insulin family, and distinguish the potential effects of exercise on these interactions.

Sex hormone-binding globulin gene expression and insulin resistance

CONTEXT

The plasma level of sex hormone binding globulin (SHBG), a glycoprotein produced by hepatocytes, is subject to genetic, hormonal, metabolic, and nutritional regulation, and is a marker for the development of the metabolic syndrome and diabetes.

OBJECTIVE

Because the mechanism for these associations is unclear, and no studies of SHBG gene expression in humans have been published, SHBG mRNA was measured in human liver samples and related to anthropometric data.

SETTING

Inpatients at a private, nonprofit, university-associated hospital were studied.

PARTICIPANTS

Subjects were fifty five adult men and women undergoing hepatic resection as treatment for cancer.

MAIN OUTCOME MEASURES

Main outcome measures were SHBG mRNA and serum SHBG levels.

RESULTS

SHBG mRNA was a strong predictor of serum SHBG with higher levels of the mRNA and protein in women than in men. The relationship between SHBG mRNA and circulating SHBG differed in males and females consistent with a sex difference in post-transcriptional regulation. A strong positive correlation was found between the level of the mRNA for the transcription factor HNF4α and SHBG mRNA. Insulin resistance (IR), assessed by homeostatis model assessment, was related inversely to SHBG mRNA and to HNF4α mRNA as well as to circulating SHBG levels. These mRNAs, as well as serum SHBG, were higher when the hepatic triglyceride concentration was low, and decreased with increasing body mass index but were unrelated to age.

CONCLUSIONS

Fat accumulation in liver and IR are important determinants of SHBG gene expression and thereby circulating SHBG levels that are perhaps mediated through effects on the transcription factor HNF4α. These findings provide a potential mechanism to explain why low SHBG predicts the development of type 2 diabetes.

Sugar-sweetened beverage intake in relation to semen quality and reproductive hormone levels in young men

STUDY QUESTION

Is consumption of sugar-sweetened beverages (SSB) associated with semen quality?

SUMMARY ANSWER

Higher consumption of SSB was associated with lower sperm motility among healthy, young men.

WHAT IS KNOWN ALREADY

The existing literature on the potential role of SSBs on male reproductive function is scarce and primarily focused on the relation between caffeinated beverages and semen quality. However, a rodent model suggests that SSBs may hamper male fertility.

STUDY DESIGN, SIZE, DURATION

The Rochester Young Men's Study; a cross-sectional study of 189 healthy young men carried out at the University of Rochester during 2009-2010.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Men aged 18-22 years provided semen and blood samples, underwent a physical examination and completed a previously validated food frequency questionnaire (FFQ). Linear regression was used to analyze the association of SSBs with sperm parameters and reproductive hormone levels while adjusting for potential confounders.

MAIN RESULTS AND THE ROLE OF CHANCE

SSB intake was inversely related to progressive sperm motility. Men in the highest quartile of SSB intake (≥1.3 serving/day) had 9.8 (95% CI: 1.9,17.8) percentage units lower progressive sperm motility than men in the lowest quartile of intake (<0.2 serving/day) (P, trend = 0.03). This association was stronger among lean men (P, trend = 0.005) but absent among overweight or obese men (P, trend = 0.98). SSB intake was unrelated to other semen quality parameters or reproductive hormones levels.

LIMITATIONS, REASONS FOR CAUTION

As in all cross-sectional studies, causal inference is limited. An additional problem is that only single semen sample was obtained from each subject.

WIDER IMPLICATIONS OF THE FINDINGS

To our knowledge, this is the first report on the relation between SSB intake and low semen quality beyond the contribution of caffeinated beverages. While our findings are in agreement with recent experimental data in rodents, more studies are required to draw conclusions on the relation of SSB with semen quality or male infertility.

STUDY FUNDING/COMPETING INTEREST(S)

Supported by the European Union Seventh Framework Program (Environment), 'Developmental Effects of Environment on Reproductive Health' (DEER) grant 212844. Grant P30 DK046200 and Ruth L. Kirschstein National Research Service Award T32 DK007703-16 and T32HD060454 from the National Institutes of Health. None of the authors has any conflicts of interest to declare.

Insulin, estrogen, inflammatory markers, and risk of benign proliferative breast disease

Women with benign proliferative breast disease (BPBD) are at increased risk for developing breast cancer. Evidence suggests that accumulation of adipose tissue can influence breast cancer development via hyperinsulinemia, increased estrogen, and/or inflammation. However, there are limited data investigating these pathways with respect to risk of BPBD. We evaluated serologic markers from these pathways in a case-control study of postmenopausal women nested within the Women's Health Initiative Clinical Trial. Cases were the 667 women who developed BPBD during follow-up, and they were matched to 1,321 controls. Levels of insulin, estradiol, C-reactive protein (CRP), and adiponectin were measured in fasting serum collected at baseline. Conditional logistic regression models were used to estimate ORs for the association of each factor with BPBD risk. Among nonusers of hormone therapy, fasting serum insulin was associated with a statistically significant increase in risk of BPBD (OR for highest vs. lowest quartile = 1.80; 95% confidence interval, CI, 1.16-2.79; Ptrend = 0.003) as were levels of estradiol (OR for highest vs. lowest tertile = 1.89; 95% CI, 1.26-2.83; Ptrend = 0.02) and CRP (OR for highest vs. lowest quartile = 2.46; 95% CI, 1.59-3.80; Ptrend < 0.001). Baseline adiponectin level was inversely associated with BPBD risk (OR for highest vs. lowest quartile = 0.47; 95% CI, 0.31-0.71; Ptrend < 0.001). These associations persisted after mutual adjustment, but were not observed among users of either estrogen alone or of estrogen plus progestin hormone therapy. Our results indicate that serum levels of estrogen, insulin, CRP, and adiponectin are independent risk factors for BPBD and suggest that the estrogen, insulin, and inflammation pathways are associated with the early stages of breast cancer development.

Intensive insulin therapy increases sex hormone-binding globulin in newly diagnosed type 2 diabetic patients

OBJECTIVE

Many studies have shown that low sex hormone-binding globulin (SHBG) is associated with insulin resistance, but only few studies have examined how serum SHBG is regulated by insulin in humans. This interventional study aimed to investigate the effect of insulin therapy (IT) on serum SHBG levels in newly diagnosed type 2 diabetic patients.

METHODS

A total of 80 newly diagnosed type 2 diabetic subjects were enrolled and randomly grouped into a 2-week intensive IT with/without metformin. Serum SHBG, total testosterone, glucose, liver enzymes, lipids, insulin, and C-peptide levels were measured before and after IT.

RESULTS

Before IT, serum SHBG levels were negatively correlated with BMI, waist circumference (WC), alanine aminotransferase (ALT), gamma-glutamyl transpeptidase (γ-GT), triglyceride (TG), fasting insulin, and C-peptide, and homeostatic model assessment of insulin resistance (HOMA-IR), and positively with HDL-C (all P for trend <0.05), after adjustment for age and sex. IT increased serum SHBG levels from 26.5±14.5 to 33.2±15.0 nmol/l (P<0.001), increased by 25.2% (95% CI, 20.3 to 30.9%, P<0.001). In a multiple linear regression model adjusting for age, sex, BMI, and WC, the decreases in ΔALT (standardized regression coefficient β=-0.374, P=0.012) and ΔTG (β=-0.380, P=0.020) were independent contributors to the increase in ΔSHBG.

CONCLUSIONS

IT increases serum SHBG likely through improving insulin resistance and liver function.

[Poor prognostic value of weight change during chemotherapy in non-metastatic breast cancer patients: causes, mechanisms involved and preventive strategies]

Numerous studies have demonstrated that a significant change in weight during chemotherapy treatment was a factor of poor prognosis in early breast cancer women. However, the causes and mechanisms involved in this phenomenon are not fully known. This review summarizes current knowledge about the causes of energy imbalance during chemotherapy treatment and the mechanisms that have been proposed as responsible for the increased risk of relapse and death in this population. Current preventive strategies focus on physical activity programs but also on the use of metformin during and after chemotherapy.

A twenty-first century cancer epidemic caused by obesity: the involvement of insulin, diabetes, and insulin-like growth factors

Obesity has reached epidemic proportions in the developed world. The progression from obesity to diabetes mellitus type 2, via metabolic syndrome, is recognised, and the significant associated increase in the risk of major human cancers acknowledged. We review the molecular basis of the involvement of morbidly high concentrations of endogenous or therapeutic insulin and of insulin-like growth factors in the progression from obesity to diabetes and finally to cancer. Epidemiological and biochemical studies establish the role of insulin and hyperinsulinaemia in cancer risk and progression. Insulin-like growth factors, IGF-1 and IGF-2, secreted by visceral or mammary adipose tissue have significant paracrine and endocrine effects. These effects can be exacerbated by increased steroid hormone production. Structural studies elucidate how each of the three ligands, insulin, IGF-1, and IGF-2, interacts differently with isoforms A and B of the insulin receptor and with type I IGF receptor and explain how these protagonists contribute to diabetes-associated cancer. The above should inform appropriate treatment of cancers that arise in obese individuals and in those with diabetes mellitus type 2. Novel drugs that target the insulin and insulin-like growth factor signal transduction pathways are in clinical trial and should be effective if appropriate biomarker-informed patient stratification is implemented.

Sex hormone-binding globulin and the risk for metabolic syndrome in children of South Asian Indian origin

OBJECTIVE

To determine whether the plasma level of sex hormone-binding globulin (SHBG) identifies South Asian Indian children at risk for metabolic syndrome.

METHODS

Adults and their children aged 5 to 9 years were recruited at the annual health fair at the Hindu temple serving the South Asian Indian community in Louisville, Kentucky. Anthropometric data were collected in adults and children, and blood pressure, lipid, and glucose levels were measured in adults. SHBG levels were measured in children using a fingerstick blood sample. In adults, metabolic syndrome was diagnosed according to the International Diabetes Federation criteria. Twelve months later, follow-up anthropometric data were obtained for a portion of the children.

RESULTS

The study included 30 sets of parents and 30 children. The prevalence of metabolic syndrome among 310 adults attending the health fair was 42% in men and 39% in women. Children with 1 parent with metabolic syndrome had 24% lower SHBG levels that increased to 55% if both parents had metabolic syndrome. SHBG levels were inversely related to waist circumference and to body mass index percentile. Both SHBG and waist circumference predicted weight gain over 1 year in children. CONCLUSIONS Low SHBG levels were found in South Asian Indian children whose parents had attributes of metabolic syndrome. The dose dependency of SHBG is consistent with inheritance of a genetic trait, and if the results are applicable to other racial/ethnic groups, SHBG may be a useful marker to identify at-risk children for early intervention.