Waist circumference and serum adiponectin levels in obese and non-obese postmenopausal women

Bone Marrow Adipose Tissue as a Critical Regulator of Postmenopausal Osteoporosis - A Concise Review

Postmenopausal osteoporosis (PMOP) is a major health problem affecting millions of women worldwide. PMOP patients are often accompanied by abnormal accumulation of bone marrow adipose tissue (BMAT). BMAT is a critical regulator of bone homeostasis, and an increasing BMAT volume is negatively associated with bone mass reduction or fracture. BMAT regulates bone metabolism via adipokines, cytokines and the immune system, but the specific mechanisms are largely unknown. This review emphasizes the impact of estrogen deficiency on bone homeostasis and BMAT expansion, and the mechanism by which BMAT regulates PMOP, providing a promising strategy for targeting BMAT in preventing and treating PMOP.

Linoleic Acid-Rich Oil Supplementation Increases Total and High-Molecular-Weight Adiponectin and Alters Plasma Oxylipins in Postmenopausal Women with Metabolic Syndrome

BACKGROUND

The onset of menopause increases the risk of metabolic syndrome (MetS). Adiponectin is an adipokine associated with insulin sensitivity that is lower in people with MetS. Supplementing diets with linoleic acid (LA)-rich oil increased adiponectin concentrations and improved glucose control in women with type 2 diabetes. The effect of LA on adipokines, especially total and the bioactive form of adiponectin, high-molecular-weight (HMW) adiponectin, in women with MetS is unknown.

OBJECTIVES

The aim of this study was to explore the effect of supplementation of the diet with an oil rich in LA on adipokines in women with MetS. The effect of the LA-rich oil (LA-oil) on oxylipins, key metabolites that may influence inflammation and metabolism, was also explored.

METHODS

In this open-label single-arm pilot study, 18 postmenopausal nondiabetic women with MetS enrolled in a 2-phase study were instructed to consume LA-rich vegetable oil (10 mL/d) as part of their habitual diets. Women consumed an oleic acid-rich oil (OA-oil) for 4 wk followed by an LA-oil for 16 wk. Fasting concentrations of adipokines, fatty acids, oxylipins, and markers of glycemia and inflammation were measured.

RESULTS

After 4 wk of OA-oil consumption, fasting glucose and total adiponectin concentrations decreased whereas fasting C-reactive protein increased. After 16 wk of LA-oil supplementation total and HMW adiponectin and plasma oxylipins increased. Markers of inflammation and glycemia were unchanged after LA-oil consumption.

CONCLUSIONS

Supplementation with LA-oil increased total and HMW adiponectin concentrations and altered plasma oxylipin profiles. Larger studies are needed to elucidate the links between these changes and MetS.This trial was registered at clinicaltrials.gov as NCT02063165.

Correlation of Serum Adiponectin and Leptin levels in Obesity and Type 2 Diabetes Mellitus

INTRODUCTION

Indian phenotype includes higher waist circumference despite lower body mass index, thereby making Indians more prone to diabetes and its complications.

AIM

The present study aimed to analyze the serum levels of adiponectin and leptin in the participants with type 2 diabetes mellitus (T2DM) and obesity and their correlation with hypertension and dyslipidemia.

MATERIALS AND METHODS

In the study, 50 diabetics and 50 controls aged between 40 and 60 years were included in the study.

RESULTS

Adiponectin levels were significantly higher in diabetics than in nondiabetic participants irrespective of gender (P ≤ 0.04 in males, P ≤ 0.02 in females). Leptin levels were significantly higher in diabetics compared to nondiabetics (P ≤ 0.001) in both males and females.

CONCLUSION

Adiponectin and leptin levels may be used as important clinical markers for T2DM and obesity.

The role of adipokines in chronic inflammation

Adipose tissue has traditionally been defined as connective tissue that stores excess calories in the form of triacylglycerol. However, the physiologic functions attributed to adipose tissue are expanding, and it is now well established that adipose tissue is an endocrine gland. Among the endocrine factors elaborated by adipose tissue are the adipokines; hormones, similar in structure to cytokines, produced by adipose tissue in response to changes in adipocyte triacylglycerol storage and local and systemic inflammation. They inform the host regarding long-term energy storage and have a profound influence on reproductive function, blood pressure regulation, energy homeostasis, the immune response, and many other physiologic processes. The adipokines possess pro- and anti-inflammatory properties and play a critical role in integrating systemic metabolism with immune function. In calorie restriction and starvation, proinflammatory adipokines decline and anti-inflammatory adipokines increase, which informs the host of energy deficits and contributes to the suppression of immune function. In individuals with normal metabolic status, there is a balance of pro- and anti-inflammatory adipokines. This balance shifts to favor proinflammatory mediators as adipose tissue expands during the development of obesity. As a consequence, the proinflammatory status of adipose tissue contributes to a chronic low-grade state of inflammation and metabolic disorders associated with obesity. These disturbances are associated with an increased risk of metabolic disease, type 2 diabetes, cardiovascular disease, and many other pathological conditions. This review focuses on the impact of energy homeostasis on the adipokines in immune function.

Thickness of preperitoneal fat as a predictor of malignancy in overweight and obese women with endometrial polyps

The aim of the present study was to determine the association between the thickness of preperitoneal fat (PFT), utilized as an indicator of visceral fat deposition, and the risk of premalignant and malignant changes of endometrial polyps (EPs) in overweight and obese women. Overweight and obese women who had undergone diagnostic outpatient hysteroscopy and subsequent endometrial polypectomy between January 2010 and May 2013 were analyzed. Each patient underwent a transabdominal ultrasound for the purpose of measuring the thickness of preperitoneal fat. A total of 146 overweight or obese women were analyzed. The overall incidence of malignant or premalignant lesions was 8.2%. Notably, 5 patients (3.4%) received a histopathological diagnosis of complex hyperplasia with atypia, while polyps harboring carcinoma were diagnosed in 7 cases (4.8%). A significantly increased PFT was observed in women exhibiting preneoplastic and neoplastic lesions, compared with women with benign EPs (mean ± SD, 23.2±3.7 vs. 15.9±8.3; P<0.01). Patient age of >60 years was significantly associated with malignant progression of EPs, while body mass index, menopausal status, arterial hypertension, diabetes, abnormal uterine bleeding, hormone replacement therapy and tamoxifen treatment demonstrated no significant association with the development of preneoplastic and neoplastic lesions of the endometrium. In a multivariate analysis, only PFT maintained a significant correlation with the diagnosis of preneoplastic and neoplastic lesions on EPs (odds ratio, 1.14; 95% confidence interval, 1.04-1.26). Ultrasound evaluation of PFT in overweight and obese women may be useful for the identification of a particularly high-risk subgroup of women. Therefore, regardless of symptoms or additional clinical variables, these particularly high-risk women require appropriate counseling and prompt surgical removal of EPs.

Nonalcoholic fatty liver disease and metabolic syndrome in postmenopausal women

Nonalcoholic fatty liver disease (NAFLD) is considered the most common cause of chronic liver disease in the Western countries. NAFLD includes a spectrum ranging from a simple steatosis to a nonalcoholic steatohepatitis (NASH) which is defined by the presence of inflammatory infiltrate, cellular necrosis, hepatocyte ballooning, and fibrosis and cirrhosis that can eventually develop into hepatocellular carcinoma. Studies emphasize the role of insulin resistance, oxidative stress, pro-inflammatory cytokines, adipokines in the development and progression of NAFLD. It seems to be independently associated with type II diabetes mellitus, increased triglycerides, decreased HDL-cholesterol, abdominal obesity and insulin resistance. These findings are in accordance with the criteria used in the diagnosis of metabolic syndrome (MetS). Here, we will discuss the current knowledge on the epidemiology, pathophysiology and diagnosis of NAFLD and the association of metabolic syndrome in postmenopausal women.

Comparative effect of two Mediterranean diets versus a low-fat diet on glycaemic control in individuals with type 2 diabetes

BACKGROUND/OBJECTIVES

Although benefits have been attributed to the Mediterranean diet, its effect on glycaemic control has not been totally elucidated. The aim of this work was to compare the effect of two Mediterranean diets versus a low-fat diet on several parameters and indices related to glycaemic control in type 2 diabetic subjects.

SUBJECTS/METHODS

A multicentric parallel trial was conducted on 191 participants (77 men and 114 women) of the PREDIMED study in order to compare three dietary interventions: two Mediterranean diets supplemented with virgin olive oil (n=67; body mass index (BMI)=29.4±2.9) or mixed nuts (n=74; BMI=30.1±3.1) and a low-fat diet (n=50; BMI=29.8±2.8). There were no drop-outs. Changes in body weight and waist circumference were determined. Insulin resistance was measured by HOMA-IR index, adiponectin/leptin and adiponectin/HOMA-R ratios after 1 year of follow-up.

RESULTS

Increased values of adiponectin/leptin ratio (P=0.043, P=0.001 and P<0.001 for low-fat, olive oil and nut diets, respectively) and adiponectin/HOMA-IR ratio (P=0.061, P=0.027 and P=0.069 for low-fat, olive oil and nut diets, respectively) and decreased values of waist circumference (P=0.003, P=0.001 and P=0.001 for low-fat, olive oil and nut diets, respectively) were observed in the three groups. In both Mediterranean diet groups, but not in the low-fat diet group, this was associated with a significant reduction in body weight (P=0.347, P=0.003 and P=0.021 for low-fat, olive oil and nut diets, respectively).

CONCLUSIONS

Mediterranean diets supplemented with virgin olive oil or nuts reduced total body weight and improved glucose metabolism to the same extent as the usually recommended low-fat diet.

Association between interleukin 1β and interleukin 10 concentrations: a cross-sectional study in young adolescents in Taiwan

Background

In adults, low circulating interleukin 10 (IL10) has been associated with obesity and type 2 diabetes. However, studies investigating IL10 in overweight and obese children have yielded conflicting results. The aim of this study was to investigate factors associated with serum IL10 concentration in young Chinese adolescents.

Methods

Young adolescents (n=325) ages 13.33±1.10 years were recruited into the cross-sectional study from 2010 to 2011. Parameters of obesity, individual components of MetS, iron status and serum IL10 were evaluated.

Results

Compared with their normal weight counterparts, overweight adolescents had lower serum IL10 but higher TNFα, nitric oxide (NO) and IL1β concentrations (all p<0.05). Obese adolescents had increased IL1β but decreased hepcidin concentration compared with normal weight (p<0.01 and p<0.05; respectively). A strong inverse relationship (p<0.0001) was found between IL10 and pro-inflammatory cytokines (TNFα and IL1β). Multivariate linear regression analysis showed serum IL1β was significantly correlated with IL10 (β=−0.156, p<0.0001). When overweight and obese adolescents were assessed separately from normal weight, only IL1β was inversely associated with serum IL10 (β=−0.231, p=0.0009). The association between IL10 and IL1β was weaker in adolescents with normal weight (β=−0.157, p=0.0002), after adjusting for gender, TNFα, IFNγ and NO.

Conclusions

Our study confirmed that low IL10 concentration is associated with overweight and obesity in young adolescents. We also demonstrated for the first time that pro-inflammatory cytokine IL1β is independently associated with IL10. A decline in IL10 concentration in overweight and obese adolescents may further contribute to the IL1β-mediated inflammatory environment associated with obesity.

Increase in MMP-2 activity in overweight and obese women is associated with menopausal status

BACKGROUND

Metalloproteinases (MMPs) are synthesized in the subendothelium and are involved in the atherosclerosis and cardiovascular disease process because of their major significance in vascular remodeling and plaque rupture. MMPs are also synthesized in adipose tissue during angiogenesis; however, the role of these enzymes in obesity and insulin-resistant states is still controversial.

OBJECTIVE

To evaluate MMP-2 activity in the circulation of overweight and obese women and in normal-weight controls, and to associate the levels of these factors with metabolic, adipose tissue and inflammation biomarkers.

METHODS

Plasma MMP-2 activity, adiponectin and C-reactive protein concentration, lipoprotein profile and HOMA were determined in 39 healthy women (13 normal weight and 26 overweight/obese).

RESULTS

Overweight/obese women were older (p < 0.001) than normal-weight women; 20/26 of overweight/obese women were postmenopausal compared with 4/13 of normal-weight women. Overweight/obese women had significantly higher plasma activity of MMP-2 than controls (mean relative area: 0.81 (range 0.4-1.92) vs. 1.33 (range 0.4-3.1); p < 0.005); this difference was lost after adjusting for menopausal status. MMP-2 activity positively correlated with waist circumference (p < 0.002), HOMA (p < 0.003), and high-sensitivity C-reactive protein (p < 0.05), apolipoprotein B (p = 0.006) and triglyceride/high density lipoprotein (HDL) cholesterol index (p < 0.001), and negatively with HDL cholesterol (p < 0.001), HDL2 cholesterol (p < 0.008), HDL3 cholesterol (p < 0.05) and adiponectin (p < 0.05). The association with HOMA and adiponectin persisted even after adjusting for menopausal status.

CONCLUSION

Our finding of increased plasma activity of MMP-2 in overweight/obese women, associated with menopausal status, is important given that it fits in with an early stage of cardiovascular disease; the association of MMP-2 activity with obesity markers may be a link between adipose tissue and risk for cardiovascular disease.

Neuropeptide Y mediates the short-term hypometabolic effect of estrogen deficiency in mice

BACKGROUND

Estrogen deficiency increases body weight or total and central adiposity and decreases energy expenditure. Hypothalamic neuropeptide Y (NPY) expression is altered by estrogen deficiency in rodents, but the long-term consequences on energy homeostasis are unknown.

OBJECTIVE

To investigate the role of NPY in the changes in energy expenditure and physical activity, as well as the associated changes in body weight and composition in response to short-term and long-term estrogen deficiency.

DESIGN

Sham and ovariectomy (OVX) operations were performed at 8 weeks of age in wild-type (WT) and NPY(-/-) mice. Energy expenditure, physical activity, body composition and weight, as well as food intake were measured at 10-18 days (short-term) and 46-54 days (long-term) after OVX.

RESULTS

OVX influences energy homeostasis differently at early compared with later time-points. At the early but not the late time point, OVX in WT mice reduced oxygen consumption and energy expenditure and tended to reduce resting metabolic rate. Interestingly, these effects of short-term estrogen deficiency were ablated by NPY deletion, with NPY(-/-) mice exhibiting significant increases in energy expenditure and resting metabolic rate. In addition to these hypermetabolic effects, OVX NPY(-/-) mice exhibited significantly lower body weight and whole-body fat mass relative to OVX WT controls at the short-term but not the long-term time point. Food intake and physical activity were unaltered by OVX, but NPY(-/-) mice exhibited significant reductions in these parameters relative to WT.

CONCLUSION

The effects of estrogen deficiency to reduce energy metabolism are transient, and NPY is critical to this effect as well as the early OVX-induced obesity.

Obesity and breast cancer: a clinical biochemistry perspective

OBJECTIVES

To evaluate the laboratory diagnosis aspects of obesity-related health problems with special reference to postmenopausal breast cancer.

DESIGN AND METHODS

We conducted a systemic search of the literature primarily from the PubMed to obtain the relevant data.

RESULTS

Obesity is associated with the dysregulations of a number of body components such as blood constituents, extracellular matrix, and hormones/growth factors axes, which could be utilized for early diagnosis.

CONCLUSIONS

Obesity-related disorders including breast cancer have emerged as major health problems in almost all the nations. There is a need to elucidate different biochemical markers that are being used in the clinics or have the potential for such use. A precise understanding of the complex pathologies related with obesity is useful in prevention, early diagnosis and overall clinical management.