Insulin resistance is a major risk factor for developing type 2 diabetes caused by the inability of insulin-target tissues to respond properly to insulin, and contributes to the morbidity of obesity. Insulin action involves a series of signaling cascades initiated by insulin binding to its receptor, eliciting receptor autophosphorylation and activation of the receptor tyrosine kinase, resulting in tyrosine phosphorylation of insulin receptor substrates (IRSs). Phosphorylation of IRSs leads to activation of phosphatidylinositol 3-kinase (PI3K) and, subsequently, to activation of Akt and its downstream mediator AS160, all of which are important steps for stimulating glucose transport induced by insulin. Although the mechanisms underlying insulin resistance are not completely understood in skeletal muscle, it is thought to result, at least in part, from impaired insulin-dependent PI3K activation and downstream signaling. This review focuses on the molecular basis of skeletal muscle insulin resistance in obesity and type 2 diabetes. In addition, the effects of insulin-sensitizing agent treatment and lifestyle intervention of human insulin-resistant subjects on insulin signaling cascade are discussed. Furthermore, the role of Rho-kinase, a newly identified regulator of insulin action in insulin control of metabolism, is addressed.
Blood Glucose/*metabolism ; Diabetes Mellitus, Type 2/*metabolism ; Humans ; Insulin/metabolism ; Insulin Resistance/*physiology ; Obesity, Abdominal/*metabolism ; Signal Transduction/physiology

Adipose tissue is a highly heterogeneous endocrine organ. The heterogeneity among different anatomical depots stems from their intrinsic differences in cellular and physiological properties, including developmental origin, adipogenic and proliferative capacity, glucose and lipid metabolism, insulin sensitivity, hormonal control, thermogenic ability and vascularization. Additional factors that influence adipose tissue heterogeneity are genetic predisposition, environment, gender and age. Under obese condition, these depot-specific differences translate into specific fat distribution patterns, which are closely associated with differential cardiometabolic risks. For instance, individuals with central obesity are more susceptible to developing diabetes and cardiovascular complications, whereas those with peripheral obesity are more metabolically healthy. This review summarizes the clinical and mechanistic evidence for the depot-specific differences that give rise to different metabolic consequences, and provides therapeutic insights for targeted treatment of obesity.
Adipose Tissue ; Adipose Tissue, White* ; Genetic Predisposition to Disease ; Glucose ; Insulin Resistance ; Lipid Metabolism ; Obesity ; Obesity, Abdominal ; Population Characteristics*

OBJECTIVE: We aimed to explore the association between obesity and depression and the role of systemic inflammation in older adults. METHODS: Adults ≥ 65 years old ( n = 1,973) were interviewed at baseline in 2018 and 1,459 were followed up in 2021. General and abdominal obesity were assessed, and serum C-reactive protein (CRP) levels were measured at baseline. Depression status was assessed at baseline and at follow-up. Logistic regression was used to analyze the relationship between obesity and the incidence of depression and worsening of depressive symptoms, as well as the relationship between obesity and CRP levels. The associations of CRP levels with the geriatric depression scale, as well as with its three dimensions, were investigated using multiple linear regressions. RESULTS: General obesity was associated with worsening depression symptoms and incident depression, with an odds ratio ( OR) [95% confidence interval ( CI)] of 1.53 (1.13-2.12) and 1.80 (1.23-2.63), especially among old male subjects, with OR (95% CI) of 2.12 (1.25-3.58) and 2.24 (1.22-4.11), respectively; however, no significant relationship was observed between abdominal obesity and depression. In addition, general obesity was associated with high levels of CRP, with OR (95% CI) of 2.58 (1.75-3.81), especially in subjects free of depression at baseline, with OR (95% CI) of 3.15 (1.97-5.04), and CRP levels were positively correlated with a score of specific dimension (life satisfaction) of depression, P < 0.05. CONCLUSION General obesity, rather than abdominal obesity, was associated with worsening depressive symptoms and incident depression, which can be partly explained by the systemic inflammatory response, and the impact of obesity on depression should be taken more seriously in the older male population.
Humans ; Male ; Aged ; Depression/etiology* ; C-Reactive Protein/metabolism* ; Obesity, Abdominal/epidemiology* ; Longitudinal Studies ; Inflammation/epidemiology* ; Obesity/complications*

Obesity is characterized by abnormal and excessive adipose tissue accumulated in the body. Compared with peripheral obesity (the accumulation of subcutaneous adipose tissue), abdominal obesity (the accumulation of visceral adipose tissue) is associated with increased risk of the metabolic syndrome, such as diabetes, hypertension, atherosclerosis, and dyslipidemia. Adipose tissue is a highly heterogeneous endocrine organ. Adipose tissue depots differ significantly in anatomy, cell biology, glucose and lipid metabolism as well as in endocrine regulation. Visceral adipose tissue has a stronger metabolic activity and secrets a larger amount of free fat acids, adipocytokines, hormones and inflammatory factors, which flux into the liver directly via the hepatic portal vein. These characteristics indicate that visceral adiposity may lead to the metabolic syndrome and thus visceral adipose tissue might be the clinical target for the prevention and treatment of obesity.
Adipose Tissue ; pathology ; Humans ; Intra-Abdominal Fat ; pathology ; Lipid Metabolism ; Metabolic Syndrome ; physiopathology ; Obesity ; physiopathology ; Obesity, Abdominal ; physiopathology ; Subcutaneous Fat ; pathology

A coffee enema which has been suggested as a part of a cancer treatment, has been misused as a treatment for obesity and constipation among the general population. Its proponents claim that caffeine is absorbed in the colon, which leads to vasodilatation in the liver and stimulation of the hepatocellular function to detoxify the products of the tumor cell metabolism. However, the clinical efficacy of the anti-cancer effect of coffee enemas has not been demonstrated. Many side effects of coffee enemas have been reported. These include severe electrolyte imbalance, polymicrobial enteric septicemia, and even death. We experienced a patient who presented with abdominal pain and a bloody stool after receiving a coffee enema to relieve constipation. We report this case of coffee enema-induced colitis with a review of the relevant.
Abdominal Pain ; Caffeine ; Coffee* ; Colitis* ; Colon ; Constipation ; Enema ; Humans ; Liver ; Metabolism ; Obesity ; Sepsis ; Vasodilation

BACKGROUND: The purpose of this study is to analyze the effects of an abdominal obesity management program in middle-aged women in Korea. METHODS: Examination of databases, including the Research Information Sharing Service, Database Periodical Information Academic, and Korean Studies Information, resulted in identification of 772 studies performed up to 2014, of which 43 satisfied the inclusion data. Data analysis was performed using R version 3.2 to calculate the effect sizes, explore possible causes of heterogeneity, and check for publication bias, using a funnel plot and its trim-and-fill analysis. RESULTS: The mean effect size of the management program was small (g=0.22), along with the anthropometric index (g=0.18), metabolism index (g=0.21), fat-distribution (g=0.36), and inflammatory index (g=0.36). Moderator analysis was performed to determine heterogeneity, but no significant differences were found between the randomized controlled trial (RCT) group and non-RCT group. In addition, the length of the session was found to be statistically significant after performing a meta-regression. Finally, a funnel plot with a trim-and-fill analysis was produced to check for publication bias, but no significant bias was detected. CONCLUSION: Based on these findings, the abdominal obesity management program affects middle-aged women in Korea. Further research is needed to target other age groups with abdominal obesity.
Bias (Epidemiology) ; Female ; Humans ; Information Dissemination ; Korea ; Metabolism ; Obesity, Abdominal ; Population Characteristics ; Publication Bias ; Statistics as Topic

The aim of the study was to investigate whether the expression of obestatin in gastric body mucosa in abdominal obesity patients with normal body mass index (BMI) is different compared with healthy controls. Twenty abdominal obesity patients with normal BMI and twenty healthy controls were included in the study. The number of obestatin-positive cells in gastric body mucosa was significantly lower in abdominal obesity patients with normal BMI than that in healthy subjects. There was a positive correlation between the numbers of obestatin-positive cells in the gastric body mucosa and plasma obestatin levels in abdominal obesity subjects and control group.
Adult ; Body Mass Index ; Case-Control Studies ; Female ; Gastric Mucosa ; metabolism ; Humans ; Male ; Middle Aged ; Obesity, Abdominal ; metabolism

OBJECTIVETo evaluate the changes in body fat distribution after gastric bypass in gastric cancer patients with metabolic syndrome.

METHODSFrom July 2009 to February 2010, 26 patients with gastric cancer and concurrent metabolic syndrome were prospectively enrolled and underwent gastric bypass surgery at the Fuzhou General Hospital of Nanjing Military Command. Body mass index(BMI), waist circumference, hip circumference, insulin and insulin resistance index were measured before operation and at postoperative 1, 4, 12, 24, 48 weeks.

RESULTSAfter gastric bypass surgery, metabolic syndrome was improved including obesity, hypertension, disturbance of lipid and hyperglycemia. After 48 weeks postoperatively HOMA-IR decreased from 5.7 ± 1.5 to 3.4 ± 1.0 (P<0.05). BMI decreased from (27.1 ± 3.8) kg/m(2) to (22.6 ± 1.4) kg/m(2) (P<0.05). Indices for central obesity: waist circumference decreased from (95.3 ± 2.5) cm to (75.3 ± 1.1) cm, and visceral fat area decreased from(101.7 ± 13.8) cm(2) to (78.7 ± 11.2) cm(2) (P<0.05). There were no decline in peripheral obesity indices including hip circumference and subcutaneous fat area(P>0.05).

CONCLUSIONSThe distribution of body fat after gastric bypass changes from central obesity to peripheral obesity. Improvement of insulin resistance after gastric bypass surgery is associated with the decrease in central obesity indices.

Adult ; Body Fat Distribution ; Gastric Bypass ; Humans ; Metabolic Syndrome ; metabolism ; surgery ; Middle Aged ; Obesity ; pathology ; Obesity, Abdominal ; Postoperative Period ; Prospective Studies

Metabolic syndrome is a cluster of diseases that include central obesity, hyperglycemia, dyslipidemia, and hypertension. Metabolic syndrome is a risk factor for type 2 diabetes and cardiovascular disease and the key pathophysiology is insulin resistance. Thyroid hormone has been known to play an important role in lipid and glucose metabolism and hypothyroidism causes atherosclerosis and insulin resistance. A number of clinical studies reported overt or subclinical hypothyroidism is associated with metabolic syndrome, and there has been the efforts elucidating a link between these two diseases. Recently, thyroid hormone analogue or thyromimetics has been developed to improve metabolic syndrome including dyslipidemia. I reviewed recently reported mechanisms explaining the association between hypothyroidism and metabolic syndrome, and current status of the development of thyromimetics was also reviewed.
Atherosclerosis ; Cardiovascular Diseases ; Dyslipidemias ; Glucose ; Hyperglycemia ; Hypertension ; Hypothyroidism* ; Insulin Resistance ; Metabolism ; Obesity, Abdominal ; Risk Factors ; Thyroid Gland

PURPOSE: Association of low intake of calcium (Ca) and inadequate vitamin D (VD) status with higher prevalence rates of obesity has been reported. This study was conducted in order to investigate the effects of different levels of whey Ca and VD intake on lipid metabolism in growing rats. METHODS: A total of 56 five-week-old male Sprague-Dawley rats were divided into seven groups and fed for five weeks. Ca groups were divided into three levels, low, normal, and high (0.25%, 0.5%, 1%). VD subgroups in the low and high Ca groups were divided into three levels, low, normal, and high (10 IU, 1,000 IU, and 5,000 IU). The effects of Ca and VD on each group were evaluated by two way ANOVA. RESULTS: Significantly higher amounts of abdominal fat, visceral fat, and epididymal fat were observed in the Low-Ca groups than in the Normal-Ca and High-Ca groups. Serum leptin levels of Low-Ca groups were higher than those of Normal-Ca and High-Ca groups. The highest serum parathyroid hormone concentration was observed in the low Ca.low VD group. The levels of serum 25(OH)D were significantly increased with increasing dietary VD levels. Significantly higher serum levels of triglycerides, total cholesterol, and HDL-cholesterol were observed in the low Ca groups than in the normal Ca and high Ca groups. CONCLUSION: These results indicate that low calcium intake increased serum lipid level and body fat amount.
Abdominal Fat ; Adipose Tissue ; Animals ; Calcium* ; Cholesterol ; Humans ; Intra-Abdominal Fat ; Leptin ; Lipid Metabolism* ; Male ; Obesity ; Parathyroid Hormone ; Prevalence ; Rats* ; Rats, Sprague-Dawley ; Triglycerides ; Vitamin D*