Insulin resistance and obesity

Weight Loss Supplements

Being overweight or obese can predispose people to chronic diseases and metabolic disorders such as cardiovascular illnesses, diabetes, Alzheimer's disease, and cancer, which are costly public health problems and leading causes of mortality worldwide. Many people hope to solve this problem by using food supplements, as they can be self-prescribed, contain molecules of natural origin considered to be incapable of causing damage to health, and the only sacrifice they require is economic. The market offers supplements containing food plant-derived molecules (e.g., primary and secondary metabolites, vitamins, and fibers), microbes (probiotics), and microbial-derived fractions (postbiotics). They can control lipid and carbohydrate metabolism, reduce appetite (interacting with the central nervous system) and adipogenesis, influence intestinal microbiota activity, and increase energy expenditure. Unfortunately, the copious choice of products and different legislation on food supplements worldwide can confuse consumers. This review summarizes the activity and toxicity of dietary supplements for weight control to clarify their potentiality and adverse reactions. A lack of research regarding commercially available supplements has been noted. Supplements containing postbiotic moieties are of particular interest. They are easier to store and transport and are safe even for people with a deficient immune system.

A Potential Link Between Visceral Obesity and Risk of Alzheimer's Disease

Alzheimer's disease (AD) is the most common type of dementia characterized by the deposition of amyloid beta (Aβ) plaques and tau-neurofibrillary tangles in the brain. Visceral obesity (VO) is usually associated with low-grade inflammation due to higher expression of pro-inflammatory cytokines by adipose tissue. The objective of the present review was to evaluate the potential link between VO and the development of AD. Tissue hypoxia in obesity promotes tissue injury, production of adipocytokines, and release of pro-inflammatory cytokines leading to an oxidative-inflammatory loop with induction of insulin resistance. Importantly, brain insulin signaling is involved in the pathogenesis of AD and lower cognitive function. Obesity and enlargement of visceral adipose tissue are associated with the deposition of Aβ. All of this is consonant with VO increasing the risk of AD through the dysregulation of adipocytokines which affect the development of AD. The activated nuclear factor kappa B (NF-κB) pathway in VO might be a potential link in the development of AD. Likewise, the higher concentration of advanced glycation end-products in VO could be implicated in the pathogenesis of AD. Taken together, different inflammatory signaling pathways are activated in VO that all have a negative impact on the cognitive function and progression of AD except hypoxia-inducible factor 1 which has beneficial and neuroprotective effects in mitigating the progression of AD. In addition, VO-mediated hypoadiponectinemia and leptin resistance may promote the progression of Aβ formation and tau phosphorylation with the development of AD. In conclusion, VO-induced AD is mainly mediated through the induction of oxidative stress, inflammatory changes, leptin resistance, and hypoadiponectinemia that collectively trigger Aβ formation and neuroinflammation. Thus, early recognition of VO by visceral adiposity index with appropriate management could be a preventive measure against the development of AD in patients with VO.

Effectiveness and safety of acupuncture for insulin resistance in women with polycystic ovary syndrome: A systematic review and meta-analysis

Objective

To perform a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate acupuncture's clinical effect on insulin resistance (IR) in women with polycystic ovary syndrome (PCOS).

Methods

PubMed, Cochrane Library, Embase databases, and Chinese databases, including China National Knowledge Infrastructure, Technology Journal Database, and Wanfang Database, were searched without language restrictions from inception to December 20, 2021. Only RCTs in which acupuncture had been examined as the sole or adjunctive PCOS-IR treatment were included. Our primary endpoint was the homeostasis model assessment of insulin resistance (HOMA-IR). The secondary outcomes were fasting blood glucose (FBG), fasting insulin (FINS), body mass index (BMI), and adverse events.

Results

Our analysis included 17 eligible RCTs (N = 1511 participants). Compared with other treatments, acupuncture therapy yielded a greater mean reduction in HOMA-IR (MD = -0.15; 95% CI, -0.27 to -0.03; P = 0.01) and BMI (MD = -1.47; 95% CI, -2.46 to -0.47; P = 0.004). Besides acupuncture was associated with a lower risk of adverse events than other treatments (RR, 0.15; 95% CI, 0.10 to 0.22; P < 0.01). Additionally, the combination treatment of acupuncture and medicine is more effective in improving HOMA-IR (MD = -0.91; 95% CI, -1.11 to -0.71; P < 0.01), FBG (MD = -0.30; 95% CI, -0.56 to -0.04; P = 0.02), FINS (MD = -2.33; 95% CI, -2.60 to -2.06; P < 0.01) and BMI (MD = -1.63; 95% CI, -1.94 to -1.33; P < 0.01) than medicine alone.

Conclusions

Acupuncture is relatively effective in improving HOMA-IR and BMI in PCOS-IR. Besides, it's safer than other treatments and could be an adjuvant strategy for improving PCOS-IR. Further large-scale, long-term RCTs with strict methodological standards are justified.

Exploring the associations between number of children, multi-partner fertility and risk of obesity at midlife: Findings from the 1970 British Cohort Study (BCS70)

BACKGROUND

Early parenthood, high parity, and partnership separation are associated with obesity. However, the emergence of non-marital partnerships, serial partnering and childbearing across unions, means that it is important to consider their association to obesity. This paper examined the associations between number of biological children and multi-partner fertility (MPF)-defined as having biological children with more than one partner, with obesity at midlife.

METHOD

The sample consisted of 2940 fathers and 3369 mothers in the 1970 British Cohort Study. The outcome was obesity (BMI 30 or over) at age 46. Fertility and partnership histories ascertained the number of live biological children and MPF status by age 42. The associations were tested using logistic regression adjusting for confounders at birth, age 10 and age 16. Adult factors recorded at age 42 including age at first birth, smoking status, alcohol dependency, educational attainment and housing tenure were considered as mediators.

RESULTS

For fathers, obesity odds did not differ according to number of children or MPF. In unadjusted models, mothers with one child (OR 1.24 95%CI 1.01-1.51), mothers who had two children with two partners (OR 1.45 95%CI 1.05-1.99), and mothers who had three or more children with two or more partners (OR 1.51 95%CI 1.18-1.93) had higher odds of obesity. In adjusted models, there remained an association between mothers with one child and odds of obesity (OR 1.30 95%CI 1.05-1.60). All other associations were attenuated when confounders were included.

CONCLUSIONS

Mothers who had children with multiple partners had higher odds of obesity. However this association was completely attenuated when parental and child confounders were accounted for; suggesting that this association may be explained by confounding. Mothers who had one child only may be at increased odds of obesity, however this could be due to multiple factors including age at first birth.

The impact of obesity and uncontrolled asthma during pregnancy on metabolic and inflammatory pathways

Asthma and obesity are both inflammatory complications of pregnancy and when combined contribute to an increased risk of uncontrolled asthma during pregnancy and poor perinatal outcomes. Our previous work has identified the presence of maternal asthma is associated with a proinflammatory milieu in the placenta and reduced fetal growth. The current study was designed to determine the relationships between immunomodulatory metabolic pathways and inflammation and establish whether these pathways are associated with uncontrolled asthma in obese pregnant women.Fifty-three obese (BMI >30) pregnant women were recruited prospectively. Participants were classified as having no asthma, controlled asthma, and uncontrolled asthma based on a doctor diagnosis and assessment using the Asthma Control Questionnaire (ACQ). Circulating plasma concentrations of metabolic hormones leptin, adiponectin, insulin, glucose, and extracellular vesicle (EVs) associated cytokines were measured at 18- and 36-weeks gestation.Concentrations of metabolic and inflammatory markers among obese participants with or without asthma were not significantly different throughout gestation. However total adiponectin concentrations increased as gestation progressed in obese, non-asthmatic women but did not increase in women with asthma. Plasma adiponectin and leptin levels in women with uncontrolled asthma were positively correlated with EV inflammatory markers including GM-CSF, IL-6, TNFα and IFNγ protein.This study demonstrated that most metabolic markers remain unchanged with the presence and severity of asthma in obese pregnant women. However, differences in the associations between metabolic and inflammatory pathways were observed in women with asthma and may be one of the mechanisms contributing to uncontrolled asthma in obese pregnant women.

Predictive worth of estimated glucose disposal rate: evaluation in patients with non-ST-segment elevation acute coronary syndrome and non-diabetic patients after percutaneous coronary intervention

BACKGROUND

Measurement of estimated glucose disposal rate (eGDR) has been demonstrated to be an indicator of insulin resistance (IR) and a risk sign for long-term outcomes in those with ischemic heart disease and type 2 diabetes mellitus (T2DM) having coronary artery bypass grafting (CABG). After elective percutaneous coronary intervention (PCI), the usefulness of eGDR for prognosis in those with non-ST-segment elevation acute coronary syndrome (NSTE-ACS) and non-diabetes is yet unknown.

METHODS

1510 NSTE-ACS patients with non-diabetes who underwent elective PCI in 2015 (Beijing Anzhen Hospital) were included in this study. Major adverse cardio-cerebral events (MACCEs), such as all-cause mortality, non-fatal myocardial infarction, non-fatal ischemic stroke, and also ischemia-driven revascularization, were the main outcome of follow-up. The average number of follow-up months was 41.84.

RESULTS

After multivariate Cox regression tests with confounder adjustment, the occurrence of MACCE in the lower eGDR cluster was considerably higher than in the higher eGDR cluster, demonstrating that eGDR is an independent prognostic indicator of MACCEs. In particular, as continuous variate: hazard ratio (HR) of 1.337, 95% confidence interval (CI) of 1.201-1.488, P < 0.001. eGDR improves the predictive power of usual cardiovascular risk factors for the primary endpoint. Specifically, the results for the area under the receiver operating characteristic (ROC) curve, this is AUC, were: baseline model + eGDR 0.699 vs. baseline model 0.588; P for contrast < 0.001; continuous net reclassification improvement (continuous-NRI) = 0.089, P < 0.001; and integrated discrimination improvement (IDI) = 0.017, P < 0.001.

CONCLUSION

Low eGDR levels showed a strong correlation with poor NSTE-ACS prognosis for nondiabetic patients undergoing PCI.

Insulin resistance and related factors in patients with moderate and severe traumatic brain injury

BACKGROUND

Traumatic brain injury (TBI) is associated with atherosclerosis and cardiovascular mortality. However, the causal relationship between TBI and atherosclerosis is unclear.

AIMS

This study aimed to evaluate insulin resistance in patients with TBI and its relationship with clinical and demographic characteristics of the patients.

METHODS

The case-controlled study included 60 patients with moderate and severe TBI in the chronic phase and 60 healthy controls matched for sex, age, and body mass index (BMI). Demographic characteristics, serum insulin, and fasting blood glucose levels of both groups were assessed. Insulin resistance was determined by the Homeostasis Model Assessment insulin resistance. The clinical features of the TBI group were also recorded.

RESULTS

Insulin resistance was observed to be higher in the TBI group than in the control group (46.7% vs. 18.33%, P = 0.002). However, no significant difference was determined between TBI patients with and without insulin resistance in terms of all demographic and clinical parameters examined (all P > 0.05). Age, sex, BMI, and trauma severity were not significant predictors of insulin resistance in TBI patients.

CONCLUSION

Moderate-to-severe TBI patients have more prevalent insulin resistance than healthy controls. Evaluation of insulin resistance in these patients, who currently have limited participation in life activities and healthy lifestyles, may be useful to prevent cardiovascular diseases caused by insulin resistance.

Single Nucleotide Polymorphism in the ADIPOQ Gene Modifies Adiponectin Levels and Glycemic Control in Type Two Diabetes Mellitus Patients

Diabetes mellitus (DM) is the ninth leading cause of death worldwide. Mortality from DM is largely attributed to disease complications. Glycemic control of DM patients reduces mortality. Studies indicated that the lack of glycemic control in DM patients could be influenced by the genetic background of the patients. Evidence suggests that adiponectin levels are dysregulated in DM patients with poor glycemic control. Serum adiponectin level is a heritable trait influenced by single nucleotide polymorphisms (SNPs) in the ADIPOQ gene. It is hypothesized that SNPs in ADIPOQ could modify glycemic control in DM patients. To test this hypothesis, 375 type 2 DM (T2DM) patients were recruited. Patients were classified into good vs. poor glycemic control according to hemoglobin A1c levels. Study subjects were genotyped for variations of four SNPs in ADIPOQ (rs17300539, rs266729, rs2241766, and rs1501299). Adiponectin levels were measured from the serum. Our analysis showed that reduced serum adiponectin, a longer duration of treatment, and increased insulin resistance were all significant predictors of poor glycemic control. Moreover, the T allele and the TT genotype of rs2241766 were significantly more frequent in patients with poor glycemic control (P < 0.05). Individuals with the TT genotype of rs2241766 had significantly lower levels of serum adiponectin (P < 0.05). It was concluded that lower levels of serum adiponectin and the T allele of rs2241766 SNP in ADIPOQ were associated with poor glycemic control in T2DM patients.

The Nonlinear Correlation Between a Novel Metabolic Score for Insulin Resistance and Subclinical Myocardial Injury in the General Population

BACKGROUND

Growing studies have shown that insulin resistance (IR) is associated with cardiovascular disease (CVD), while the association between IR and subclinical myocardial injury (SC-MI) remains unclear. Hence we aimed to assess the association between IR and SC-MI.

METHODS

In this cross-sectional study, we enrolled 6043 individuals (age: 58.43 ± 13.08 years; 46.2% men) free from CVD from the third National Health and Nutrition Examination Survey. A novel metabolic score for insulin resistance (METS-IR) was used as alternative markers of IR. Multivariate logistic regression and restricted cubic spline were performed to evaluate the associations between METS-IR and SC-MI.

RESULTS

The multivariate logistic regression analysis showed that after adjusting for cardiovascular metabolic risk factors, higher METS-IR was independently correlated with higher risk of SC-MI [as a quartile variable, Q4 vs Q1, OR (95% CI): 1.395 (1.147, 1.698), P = 0.001, P for trend < 0.001; as a continuous variable, per 10-unit increment, OR (95% CI): 1.869 (1.524, 2.292), P < 0.001]. Restricted cubic spline indicated that there was a J-curve connection between METS-IR and SC-MI. Threshold effect analysis ascertained an inflection point of 37 of METS-IR. The ORs (95% CIs) of per 10-unit increase of METS-IR for SC-MI were 0.707 (0.538, 0.928) and 1.327 (1.210, 1.456) on the left and right sides of the inflection point (P < 0.05), respectively. Subgroup analysis showed that the association between METS-IR and SC-MI was only statistically significant in participants without diabetes.

CONCLUSIONS

METS-IR was nonlinearly related to SC-MI in the general population without CVD.

Vitamin D Deficiency Is Inversely Associated with Homeostatic Model Assessment of Insulin Resistance

The study was conducted to comprehensively assess the association of the concentration of vitamin D in the blood and insulin resistance in non-diabetic subjects. The objective was to pool the results from all observational studies from the beginning of 1980 to August 2021. PubMed, Medline and Embase were systematically searched for the observational studies. Filters were used for more focused results. A total of 2248 articles were found after raw search which were narrowed down to 32 articles by the systematic selection of related articles. Homeostatic Model Assessment of Insulin Resistance (HOMAIR) was used as the measure of insulin resistance and correlation coefficient was used as a measure of the relationship between vitamin D levels and the insulin resistance. Risk of bias tables and summary plots were built using Revman software version 5.3 while Comprehensive meta-analysis version 3 was used for the construction of forest plot. The results showed an inverse association between the status of vitamin D and insulin resistance (r = -0.217; 95% CI = -0.161 to -0.272; p = 0.000). A supplement of vitamin D can help reduce the risk of insulin resistance; however further studies, like randomized controlled trials are needed to confirm the results.

Exercise ameliorates insulin resistance and improves ASK1-mediated insulin signalling in obese rats

Increasing evidence reveals that physical exercise is an efficient therapeutical approach in the treatment of insulin resistance (IR) and related metabolic diseases. However, the potential beneficial effects of exercise on insulin resistance and its underlying mechanisms remain unclear. Recent findings elucidated the negative role of ASK1 in repressing the glucose uptake through JNK1‐IRS1‐Akt signalling in liver. Thus, a detailed investigation of the effect of ASK1‐mediated insulin signalling on exercise‐mediated improvement of insulin sensitivity and its underlying mechanism was implemented in this study. Using a high‐fat diet‐induced IR rat model of chronic or acute swimming exercise training, we here showed that body weight and visceral fat mass were significantly reduced after chronic exercise. Moreover, chronic exercise reduced serum FFAs levels and hepatic triglyceride content. Both chronic and acute exercise promoted glucose tolerance and insulin sensitivity. Meanwhile, both chronic and acute exercise decreased ASK1 phosphorylation and improved JNK1‐IRS1‐Akt signalling. Furthermore, exercise training decreased CFLAR, CREG and TRAF1 protein levels in liver of obese rats, which are positive regulator of ASK1 activity. These results suggested that swimming exercise demonstrated to be an effective ameliorator of IR through the regulation of ASK1‐mediated insulin signalling and therefore, could present a prospective therapeutic mean towards the treatment of IR and several metabolic diseases based on IR, containing NAFLD and type Ⅱ diabetes.

The Saturation Effect of Body Mass Index on Bone Mineral Density for People Over 50 Years Old: A Cross-Sectional Study of the US Population

Background: Previous studies had revealed that Body Mass Index (BMI) positively affected Bone Mineral Density (BMD). However, an excessively high BMI was detrimental to health, especially for the elderly. Moreover, it was elusive how much BMI was most beneficial for BMD in older adults to maintain.

Objective: To investigate whether there was a BMI saturation effect value that existed to maintain optimal BMD.

Methods: A cross-sectional study was conducted using the datasets of the National Health and Nutrition Examination Survey (NHANES) 2005–2006, 2007–2008, 2009–2010, 2013–2014, and 2017–2018. After adjusting for covariates, an analysis of the association between BMI and BMD in different femoral regions (Total femur, Femoral neck, Trochanter, Intertrochanter, and Ward's triangle) and lumbar spine regions (Total spine, L1, L2, L3, and L4) in the whole population was performed using the multivariate linear regression models, smoothing curve fitting, and saturation effects analysis models. Then, subgroup analyses were performed according to gender, age, and race.

Results: A total of 10,910 participants (5,654 males and 5,256 females) over 50 years were enrolled in this population-based study. Multivariate linear regression analyses in the population older than 50 years showed that BMI was positively associated with femoral BMD and lumbar spine BMD (P < 0.001, respectively). Smoothing curve fitting showed that the relationship between BMI and BMD was not simply linear and that a saturation value existed. The saturation effect analysis showed that the BMI saturation value was 26.13 (kg/m²) in the total femur, 26.82 (kg/m²) in the total spine, and showed site-specificity in L1 (31.90 kg/m²) and L2 (30.89 kg/m²). The saturation values were consistent with the whole participants in males, while there was high variability in the females. BMI saturation values remained present in subgroup analyses by age and race, showing specificity in some age (60–70 years old) groups and in some races.

Conclusions: Our study showed a saturation value association between BMI and BMD for people over 50 years old. Keeping the BMI in the slightly overweight value (around 26 kg/m²) might reduce other adverse effects while obtaining optimal BMD.

"Register-shift" insulin analogs uncover constraints of proteotoxicity in protein evolution

Globular protein sequences encode not only functional structures (the native state) but also protein foldability, i.e. a conformational search that is both efficient and robustly minimizes misfolding. Studies of mutations associated with toxic misfolding have yielded insights into molecular determinants of protein foldability. Of particular interest are residues that are conserved yet dispensable in the native state. Here, we exploited the mutant proinsulin syndrome (a major cause of permanent neonatal-onset diabetes mellitus) to investigate whether toxic misfolding poses an evolutionary constraint. Our experiments focused on an invariant aromatic motif (Phe^B24-Phe^B25-Tyr^B26) with complementary roles in native self-assembly and receptor binding. A novel class of mutations provided evidence that insulin can bind to the insulin receptor (IR) in two different modes, distinguished by a "register shift" in this motif, as visualized by molecular dynamics (MD) simulations. Register-shift variants are active but defective in cellular foldability and exquisitely susceptible to fibrillation in vitro Indeed, expression of the corresponding proinsulin variant induced endoplasmic reticulum stress, a general feature of the mutant proinsulin syndrome. Although not present among vertebrate insulin and insulin-like sequences, a prototypical variant ([Gly^B24]insulin) was as potent as WT insulin in a rat model of diabetes. Although in MD simulations the shifted register of receptor engagement is compatible with the structure and allosteric reorganization of the IR-signaling complex, our results suggest that this binding mode is associated with toxic misfolding and so is disallowed in evolution. The implicit threat of proteotoxicity limits sequence variation among vertebrate insulins and insulin-like growth factors.

Potential role of cinnamaldehyde and costunolide to counteract metabolic syndrome induced by excessive fructose consumption

Background

One of the serious public health problems in the world is metabolic syndrome. It includes visceral obesity, dyslipidemia, insulin resistance, hyperglycemia, and hypertension. As a contributor to almost all the classic signs of metabolic syndrome, fructose was the ideal choice. There are certain shortcomings with existing drugs for insulin-resistant treatment. Plants still represent the main source of most available medicines. Cinnamaldehyde (CNA) is an active principle of Cinnamomum zeylanicum. Costunolide (CE) is natural sesquiterpene lactones, which is the main bioactive constituent of Saussurea lappa. The main aim of the present study is to investigate the effect of the synthetic antidiabetic agent (metformin) in comparison with natural constituents (cinnamaldehyde, costunolide) after developing a reliable model for insulin resistance by using high fructose diet (HFD).

Results

It was found that HFD increased plasma glucose, insulin, glycosylated hemoglobin, HbA1c, serum total cholesterol, LDL-cholesterol, triglyceride, ALT, AST, creatinine, and uric acid. Moreover, HFD decreased hepatic reduced glutathione and superoxide dismutase levels. While oral administration of cinnamaldehyde and costunolide significantly decreased plasma glucose, HbA1c, total cholesterol, LDL-cholesterol, triglyceride, and increased level of hepatic reduced glutathione and superoxide dismutase activity. Also, cinnamaldehyde and costunolide restored the altered plasma levels of ALT, AST, creatinine, and uric acid to normal.

Conclusions

The results of this experimental study showed that cinnamaldehyde and costunolide could be used as safe drugs for treating different abnormalities of metabolic syndrome.

Inflammatory gene expression in adipose tissue according to diagnosis of anxiety and mood disorders in obese and non-obese subjects

Psychiatric disorders have been widely reported to be associated with systemic inflammation upregulation and adiposity. However, there are no data that link adipose tissue inflammation to these mental disorders. The analysis of adipokines and inflammation-related markers in adipose tissue could help to elucidate the potential association between obesity and mental health. An observational study was conducted in samples of patients consisting of non-obese and obese subjects, who were diagnosed with anxiety or mood disorders. Gene expression of adiponectin (ADIPOQ), leptin (LEP) and inflammatory markers (IL6, IL1B, TNF, CCL2, CSF3, ITGAM, and PLAUR) were determined in visceral (VAT) and subcutaneous (SAT) adipose tissues. Our results showed that the gene expression of adipokines and inflammation-related markers was higher in the VAT and SAT of obese subjects compared with non-obese subjects. Regarding mental disorders, all the inflammatory genes in the VAT were significantly higher in non-obese subjects with anxiety or mood disorders than in subjects without mental disorders, except for TNF and ITGAM. Additionally, IL6 expression was significantly lower in SAT. In contrast, obese patients diagnosed with anxiety or mood disorders only showed significantly lower expression levels of IL1B in VAT and ADIPOQ in SAT when compared with obese subjects without mental disorders. These data suggest the potential involvement of VAT inflammation in anxiety and mood disorders, involving complex mechanisms which are strongly affected by obesity.

Exercise counteracts lipotoxicity by improving lipid turnover and lipid droplet quality

The incidence of obesity and metabolic disease, such as type 2 diabetes mellitus (T2D), is rising globally. Dietary lipid over supply leads to lipid accumulation at ectopic sites, such as skeletal muscle. Ectopic lipid storage is highly correlated with insulin resistance and T2D, likely due to a loss of metabolic flexibility - the capacity to switch between fat and glucose oxidation upon insulin stimulation - and cellular dysfunction because of lipotoxicity. However, muscle lipid levels are also elevated in endurance-trained athletes, presenting a paradoxical phenotype of increased intramuscular lipids along with high insulin sensitivity - the 'athletes' paradox'. This review focuses on recent human data to characterize intramuscular lipid species in order to elucidate some of the underlying mechanisms driving skeletal muscle lipotoxicity. There is evidence that lipotoxicity is characterized by an increase in bioactive lipid species, such as ceramide. The athletes' paradox supports the notion that regular physical exercise has health benefits that might originate from the alleviation of lipotoxicity. Indeed, exercise training alleviates intramuscular ceramide content in obese individuals without a necessary decrease in ectopic lipid storage. Furthermore, evidence shows that exercise training elevates markers of lipid droplet dynamics such as the PLIN proteins, and triglyceride lipases ATGL and HSL, as well as mitochondrial efficiency, potentially explaining the improved lipid turnover and a reduction in the accumulation of lipotoxic intermediates observed with the athelets' paradox.

Bariatric Surgery Resistance: Using Preoperative Lifestyle Medicine and/or Pharmacology for Metabolic Responsiveness

Bariatric surgery is an effective and durable treatment for individuals with obesity and its associated comorbidities. However, not all patients meet weight loss and/or cardiometabolic goals following bariatric surgery, suggesting that some people are bariatric surgery resistant. The reason for this resistance is unclear, but potential factors, such as adiposity-derived inflammation, insulin resistance, hyperglycemia, and aerobic fitness prior to surgery, have been related to blunted surgery responsiveness. Exercise, diet, and/or pharmacology are effective at reducing inflammation and improving insulin action as well as physical function. Herein, we present data that supports the novel hypothesis that intervening prior to surgery can enhance disease resolution in people who are resistant to bariatric surgery.

Insulin resistance and overweight prolonged fertility-sparing treatment duration in endometrial atypical hyperplasia patients

Objective

Our previous study showed that insulin resistance (IR) was related to endometrial hyperplasia as well as endometrial cancer. But the exact impact of IR on fertility-sparing treatment in endometrial hyperplasic disease is unclear. This study investigated how IR affects fertility-sparing treatment in endometrial atypical hyperplasia (EAH) patients.

Methods

The 151 EAH patients received fertility-sparing treatment were retrospectively investigated. All patients received high-dose progestin combined with hysteroscopy. Therapeutic effects were evaluated by hysteroscopy every 3 months during the treatment.

Results

The median age was 33.0 years old (range, 21–54 years old). Sixty-one patients (40.4%) were insulin resistant. Three patients were excluded from the analysis because they chose hysterectomy within 3 months after initiation of progestin treatment. The 141 out of 148 (95.3%) patients achieved complete response (CR). No difference was found in cumulative CR rate between those with or without IR (90.2% vs. 95.6%, p=0.320). IR significantly affected therapeutic duration to achieve CR (8.1±0.5 months with IR vs. 6.1±0.4 months without IR, p=0.004). Overweight (body mass index [BMI]≥25 kg/m²) was associated with higher risk of treatment failure (odds ratio=5.61; 95% confidence interval=1.11–28.35; p=0.040) and longer therapeutic duration to achieve CR (7.6±0.5 months vs. 6.3±0.4 months, p=0.019). EAH patients with both IR and overweight (IR+BMI+) had the longest therapeutic time compared with other patients (8.8±0.6 months vs. 5.6±0.7, 6.3±0.4, and 6.4±0.8 months for IR−BMI+, IR−BMI−, and IR+BMI−, respectively, p=0.006).

Conclusion

IR and overweight were associated with longer therapeutic duration in EAH patients receiving progestin-based fertility-sparing treatment.

Protective effects of polyphenol-rich infusions from carob (Ceratonia siliqua) leaves and cladodes of Opuntia ficus-indica against inflammation associated with diet-induced obesity and DSS-induced colitis in Swiss mice

In the present study, we have investigated the effects of polyphenol-rich infusions from carob leaves and OFI-cladodes on inflammation associated with obesity and dextran sulfate sodium (DSS)-induced ulcerative colitis in Swiss mice. In vitro studies revealed that aqueous extracts of carob leaves and OFI-cladodes exhibited anti-inflammatory properties marked by the inhibition of IL-6, TNF-α and nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells concomitant with NF-κβ nucleus translocation inhibition. For in vivo investigations, Swiss male mice were subjected to control or high fat diet (HFD). At the 8th week after the start of study, animals received or not 1% infusion of either carob leaves or OFI-cladode for 4 weeks and were subjected to 2% DSS administration in drinking water over last 7 days. After sacrifice, pro-inflammatory cytokines levels in plasma and their mRNA expression in different organs were determined. Results showed that carob leaf and OFI-cladode infusions reduced inflammation severity associated with HFD-induced obesity and DSS-induced acute colitis indicated by decrease in pro-inflammatory cytokines expression (as such TNF-α, IL1b and IL-6) in colon, adipose tissue and spleen. In addition, plasma levels of IL-6 and TNF-α were also curtailed in response to infusions treatment. Thus, carob leaf and OFI-cladode infusions prevented intestinal permeability through the restoration of tight junction proteins (Zo1, occludins) and immune homeostasis. Hence, the anti-inflammatory effect of carob leaves and OFI-cladodes could be attributed to their polyphenols which might alleviate inflammation severity associated with obesity and colitis.

Customized Cooking Methods Enhance Antioxidant, Antiglycemic, and Insulin-Like Properties ofMomordica charantiaandMoringa oleifera

The current study compares antioxidant activities, total phenolic content (TPC), vitamin C content, and antiglycemic properties ofMomordica charantia(small bitter gourd) andMoringa oleifera(drumstick leaves) before and after subjecting to boiling and microwave heating for different durations. Both cooking methods enhanced the antioxidant activity and vitamin C content in the vegetables studied when cooked for five minutes and these properties declined when the cooking time was prolonged to 20 minutes. Cooking also retained or slightly improved theα-glucosidase enzyme inhibition activity of the vegetables; however, it reduced the ability of the vegetable extracts to inhibitα-amylase enzyme activity. The antioxidant activities were positively correlated with the TPC and vitamin C content in the vegetable extracts tested. The present study also evaluated the insulin-like properties (stimulation of adipogenesis) of selected vegetable extracts (five minutes microwaved). 3T3-L1 adipocytes treated with small bitter gourd extract significantly stimulated lipogenesis (in the absence of insulin) compared to drumstick leaves. Thus, the finding of this study negates the belief that cooking will reduce the nutritional value of the vegetables and also suggested that appropriate cooking method and duration for different vegetables could be selected to improve or preserve their nutritional value.

Outcomes of The BODY Project: A Program to Halt Obesity and Its Medical Consequences in High School Students

Adolescent obesity continues to be a major public health issue with a third of American adolescents being overweight or obese. Excess weight is associated with cardiovascular risk factors and pre-diabetes. High school students identified as carrying excess weight [body mass index (BMI) ≥25 kg/m(2), or BMI percentile ≥85 %] were invited to participate in The BODY Project, an intervention that included a medical evaluation and a personalized medical report of the results of that evaluation sent to the parent/guardian at home. The medical evaluation and report was repeated 12 months later. The reports also contained advice on how the individual student could modify their lifestyle to improve the specific medical parameters showing abnormalities. Outcomes were change in BMI, blood pressure, high-density lipoprotein (HDL), low-density lipoprotein (LDL), fasting glucose, and fasting insulin. Students participating in The BODY Project intervention demonstrated modest, yet significant, reductions in BMI (p < 0.001) 1 year later, and also had significant improvements in systolic blood pressure (p < 0.001) and cholesterol profile (HDL p = 0.002; LDL p < 0.001) at follow-up. The BODY Project, by means of a minimal educational program anchored on the principle of teachable moments around the students' increased perception of their own risk for disease from the medical abnormalities uncovered, demonstrates evidence of potential effectiveness in addressing adolescent obesity.

The early origins of obesity and insulin resistance: timing, programming and mechanisms

Maternal obesity is associated with an increased risk of developing gestational diabetes mellitus and it also results in an increased risk of giving birth to a large baby with increased fat mass. Furthermore, it is also contributes to an increased risk of obesity and insulin resistance in the offspring in childhood, adolescence and adult life. It has been proposed that exposure to maternal obesity may therefore result in an 'intergenerational cycle' of obesity and insulin resistance. There is significant interest in whether exposure to maternal obesity around the time of conception alone contributes directly to poor metabolic outcomes in the offspring and whether dieting in the obese mother before pregnancy or around the time of conception has metabolic benefits for the offspring. This review focusses on experimental and clinical studies that have investigated the specific impact of exposure to maternal obesity during the periconceptional period alone or extending beyond conception on adipogenesis, lipogenesis and on insulin signalling pathways in the fat, liver and muscle of the offspring. Findings from these studies highlight the need for a better evidence base for the development of dietary interventions in obese women before pregnancy and around the time of conception to maximize the metabolic benefits and minimize the metabolic costs for the next generation.

Minority Stress, Depression, Relationship Quality, and Alcohol Use: Associations with Overweight and Obesity Among Partnered Young Adult Lesbians

PURPOSE

Although lesbian women are more likely to be obese compared to heterosexual women, relatively little research has examined correlates of overweight and obesity among lesbians. The purpose of this study was to examine the association of minority stress and depression, relationship quality, and alcohol-use variables to overweight and obesity among lesbians in relationships.

METHOD

Self-identified lesbians (n=737) in current relationships completed measures of demographics, minority stress, depressive symptoms, relationship variables, and alcohol use.

RESULTS

Overweight and obesity were associated with more public identification as a lesbian, more depressive symptoms, increased heavy drinking, longer relationship length, and lower relationship consensus.

CONCLUSION

Health promotion and weight loss intervention programs for lesbians should incorporate psychological, relationship, and alcohol use components to reduce overweight and obesity among lesbians.

Leucaena leucocephala fruit aqueous extract stimulates adipogenesis, lipolysis, and glucose uptake in primary rat adipocytes

Leucaena leucocephala had been traditionally used to treat diabetes. The present study was designed to evaluate in vitro “insulin-like” activities of Leucaena leucocephala (Lam.) deWit. aqueous fruit extract on lipid and glucose metabolisms. The ability of the extract to stimulate adipogenesis, inhibit lipolysis, and activate radio-labeled glucose uptake was assessed using primary rat adipocytes. Quantitative Real-Time RT-PCR was performed to investigate effects of the extract on expression levels of genes (protein kinases B, AKT; glucose transporter 4, GLUT4; hormone sensitive lipase, HSL; phosphatidylinositol-3-kinases, PI3KA; sterol regulatory element binding factor 1, Srebp1) involved in insulin-induced signaling pathways. L. leucocephala aqueous fruit extract stimulated moderate adipogenesis and glucose uptake into adipocytes when compared to insulin. Generally, the extract exerted a considerable level of lipolytic effect at lower concentration but decreased gradually at higher concentration. The findings concurred with RT-PCR analysis. The expressions of GLUT4 and HSL genes were upregulated by twofold and onefold, respectively, whereas AKT, PI3KA, and Srebp1 genes were downregulated. The L. leucocephala aqueous fruit extract may be potentially used as an adjuvant in the treatment of Type 2 diabetes mellitus and weight management due to its enhanced glucose uptake and balanced adipogenesis and lipolysis properties.

Obesity - should we revise indications for treatment with metformin?

Introduction

Treatment of obesity with life style modifications often fails; therefore pharmacological treatment has become a very popular approach. Metformin is one of the examined possibilities. The aim of this study was to verify indications for metformin use in obese women based on metabolic and anthropometric parameters assessed by dual-X-ray absorptiometry (DXA), to establish the degree of insulin resistance and its correlations.

Material and methods

Anthropometry, fat measurement by bioimpedance and metabolic profile, including lipids, and oral glucose tolerance test (OGTT) with insulin (0 and 120 min) were performed in 50 female patients diagnosed with simple obesity, aged 18-40 years. Homeostatic model assessment HOMA-R was calculated for insulin resistance, and area under the curve (AUC) for insulin response. Total, android and gynoid fat distribution, and their ratio (A/G), were measured by DXA.

Results

From 50 women who entered the study, 33 were classified as insulin resistant (IR subgroup) and 17 as non-insulin resistant (non-IR subgroup), according to their HOMA-R indices. IR women presented higher waist circumference and DXA A/G ratio. The IR subgroup demonstrated elevated fasting triglycerides and glucose (but in the normal range) and a higher insulin response in OGTT (4.1-fold vs 2.5-fold). From different insulin measurements HOMA index turned out to have the strongest correlations with the metabolic parameters triglycerides and glucose. We found significant positive correlations between android fat and insulin: waist circumference and HOMA-R, WHR and HOMA-R, android fat and HOMA-R, A/G ratio and insulin after OGTT, and A/G ratio and HOMA-R. We found a strong correlation between WHR and A/R ratio.

Conclusions

67% of premenopausal obese women were insulin resistant. Measures of DXA visceral fat determined by android fat percentage and android/gynoid ratio were the strongest determinants of insulin resistance. Waist-to-hip ratio might be a simple method for determining the indications for metformin treatment.

AT1 receptor blockade attenuates insulin resistance and myocardial remodeling in rats with diet-induced obesity

BACKGROUND

Although obesity has been associated with metabolic and cardiac disturbances, the carrier mechanisms for these responses are poorly understood. This study analyzed whether angiotensin II blockade attenuates metabolic and cardiovascular disorders in rats with diet-induced obesity.

MATERIAL AND METHODS

Wistar-Kyoto (n = 40) rats were subjected to control (C; 3.2 kcal/g) and hypercaloric diets (OB; 4.6 kcal/g) for 30 weeks. Subsequently, rats were distributed to four groups: C, CL, OB, and OBL. L groups received Losartan (30 mg/kg/day) for five weeks. After this period we performed in vivo glucose tolerance and insulin tolerance tests, and measured triacylglycerol, insulin, angiotensin-converting enzyme activity (ACE), and leptin levels. Cardiovascular analyzes included systolic blood pressure (SBP), echocardiography, myocardial morphometric study, myosin heavy chain composition, and measurements of myocardial protein levels of angiotensin, extracellular signal-regulated (ERK1/2), c-Jun amino-terminal kinases (JNK), insulin receptor subunit β (βIR), and phosphatidylinositol 3-kinase (PI3K) by Western Blot.

RESULTS

Glucose metabolism, insulin, lipid, and ACE activity disorders observed with obesity were minimized by Losartan. Moreover, obesity was associated with increased SBP, myocardial hypertrophy, interstitial fibrosis and improved systolic performance; these effects were also minimized with Losartan. On a molecular level, OB exhibited higher ERK, Tyr-phosphorylated βIR, and PI3K expression, and reduced myocardial angiotensin and JNK expression. ERK and JNK expression were regulated in the presence of Losartan, while angiotensin, Tyr-βRI, total and Tyr-phosphorylated PI3K expression were elevated in the OBL group.

CONCLUSION

Angiotensin II blockade with Losartan attenuates obesity-induced metabolic and cardiovascular changes.

Differential effects of exposure to maternal obesity or maternal weight loss during the periconceptional period in the sheep on insulin signalling molecules in skeletal muscle of the offspring at 4 months of age

Exposure to maternal obesity before and/or throughout pregnancy may increase the risk of obesity and insulin resistance in the offspring in childhood and adult life, therefore, resulting in its transmission into subsequent generations. We have previously shown that exposure to maternal obesity around the time of conception alone resulted in increased adiposity in female lambs. Changes in the abundance of insulin signalling molecules in skeletal muscle and adipose tissue precede the development of insulin resistance and type 2 diabetes. It is not clear, however, whether exposure to maternal obesity results in insulin resistance in her offspring as a consequence of the impact of increased adiposity on skeletal muscle or as a consequence of the programming of specific changes in the abundance of insulin signalling molecules in this tissue. We have used an embryo transfer model in the sheep to investigate the effects of exposure to either maternal obesity or to weight loss in normal and obese mothers preceding and for one week after conception on the expression and abundance of insulin signalling molecules in muscle in the offspring. We found that exposure to maternal obesity resulted in lower muscle GLUT-4 and Ser 9 phospho-GSK3α and higher muscle GSK3α abundance in lambs when compared to lambs conceived in normally nourished ewes. Exposure to maternal weight loss in normal or obese mothers, however, resulted in lower muscle IRS1, PI3K, p110β, aPKCζ, Thr 642 phospho-AS160 and GLUT-4 abundance in the offspring. In conclusion, maternal obesity or weight loss around conception have each programmed specific changes on subsets of molecules in the insulin signalling, glucose transport and glycogen synthesis pathways in offspring. There is a need for a stronger evidence base to ensure that weight loss regimes in obese women seeking to become pregnant minimize the metabolic costs for the next generation.

Sugar-sweetened beverage intake and the risk of type I and type II endometrial cancer among postmenopausal women

BACKGROUND

Sugar-sweetened beverage (SSB) intake has been associated with an increased risk of obesity and type II diabetes. However, its association with endometrial cancer is unclear.

METHODS

We evaluated dietary intake of SSB, fruit juice, sugar-free beverages, sweets/baked goods, starch, and sugars among 23,039 postmenopausal women in the Iowa Women's Health Study. Incident estrogen-dependent type I and estrogen-independent type II endometrial cancers were identified via linkage with the Surveillance Epidemiology and End Results Registry. Risks of type I and type II endometrial cancers were separately compared by energy-adjusted dietary intake in Cox proportional hazards regression models.

RESULTS

From 1986 to 2010, 506 type I and 89 type II incident endometrial cancers were identified. An increased risk of type I endometrial cancer was observed with increasing SSB intake after adjustment for body mass index (BMI) and other cofounders (Ptrend = 0.0005). Compared with nondrinkers of SSB, the risk was 78% higher [95% confidence intervals (CI), 1.32-2.40] among women in the highest quintile of SSB intake. The observed association was not modified by BMI, physical activity, history of diabetes, or cigarette smoking. Higher risk of type I endometrial cancer was also observed with higher intake of sugars. None of the dietary items included in the analysis was associated with type II endometrial cancer risk.

CONCLUSION

Higher intake of SSB and sugars was associated with an increased risk of type I, but not type II, endometrial cancer.

IMPACT

SSB intake may be a risk factor for type I endometrial cancer regardless of other lifestyle factors.

The Banishing Obesity and Diabetes in Youth (BODY) Project: description and feasibility of a program to halt obesity-associated disease among urban high school students

Type 2 diabetes (T2DM) and cardiovascular disease (CVD) are rising dramatically in adolescents in parallel with excess weight. The Banishing Obesity and Diabetes in Youth (BODY) Project, is a school-based intervention that medically screens overweight and obese high school students, provides personalized feedback, and connects to appropriate healthcare. Body mass index (BMI) was determined for 1,526 students in one New York City public high school with a school-based health center (SBHC). Overweight and obese students (n = 640) were invited to complete a medical evaluation that included a survey, blood pressure and blood tests. 328/640 (51%) eligible students returned signed parental consent and participated. All participants received a personalized report detailing their results along with specific recommendations on how to improve their health. Parents of participants with results outside healthy ranges (82%; 270/328) were called and mailed referral letters to connect with healthcare services. Project staff reached by telephone 74% (199/270) of those families and 29% (58/199) stated that the report led them to make arrangements to see a healthcare provider. Most students (83%; 273/328) were registered at the SBHC, and we shared their medical results with them so they could follow-up with the students. The BODY Project is a feasible program for urban schools with a SBHC. This may allow effective prevention of T2DM, and CVD from dyslipidemia and hypertension.

Effect of chitosan, O-carboxymethyl chitosan, and N-[(2-hydroxy-3-N,N-dimethylhexadecyl ammonium)propyl] chitosan chloride on overweight and insulin resistance in a murine diet-induced obesity

Two water-soluble chitosan derivatives, O-carboxymethyl chitosan (O-CM-chitosan) and N-[(2-hydroxy-3-N,N-dimethylhexadecyl ammonium)propyl] chitosan chloride (N-CQ-chitosan), were prepared, and the therapeutic effects of chitosan, O-CM-chitosan, and N-CQ-chitosan on insulin resistance were simultaneously evaluated by rats fed on a high-fat diet. The parameters of high-fat diet-induced rats indicated that chitosan and its two derivatives not only have low cytotoxicity but can control overnutrition by fat and achieve insulin resistance therapy. However, the results in experiment in vivo showed that the therapeutic degree varied by the molecular weight and surface charge of chitosan, O-CM-chitosan, and N-CQ-chitosan. N-CQ-chitosan with a MW of 5 × 10(4) decreased body weight, the ratio of fat to body weight, triglyceride, fasting plasma glucose, fasting plasma insulin, free fatty acid, and leptin by 11, 17, 44, 46, 44, 87, and 64% and increased fecal lipid by 95%, respectively.

Study of the potential association of adipose tissue GLP-1 receptor with obesity and insulin resistance

The increase in glucagon-like peptide-1 (GLP-1) activity has emerged as a useful therapeutic tool for the treatment of type 2 diabetes mellitus. The actions of GLP-1 on β-cells and the nervous and digestive systems are well known. The action of this peptide in adipose tissue (AT), however, is still poorly defined. Furthermore, no relationship has been established between GLP-1 receptor (GLP-1R) in AT and obesity and insulin resistance (IR). We provide evidence for the presence of this receptor in AT and show that its mRNA and protein expressions are increased in visceral adipose depots from morbidly obese patients with a high degree of IR. Experiments with the 3T3-L1 cell line showed the lipolytic and lipogenic dose-dependent effect of GLP-1. Moreover, GLP-1 stimulated lipolysis in 3T3-L1 adipocytes in a receptor-dependent manner involving downstream adenylate cyclase/cAMP signaling. Our data also demonstrate that the expression of the GLP-1R in AT correlated positively with the homeostasis model assessment index in obese IR subjects. Furthermore, prospective studies carried out with patients that underwent biliopancreatic diversion surgery showed that subjects with high levels of GLP-1R expression in AT, which indicates a deficit of GLP-1 in this tissue, were those whose insulin sensitivity improved after surgery, suggesting the potential relationship between AT GLP-1R and insulin sensitivity amelioration in obese subjects. Altogether these results indicate that the GLP-1/GLP-1R system in AT represents another potential candidate for improving insulin sensitivity in obese patients.

The Banishing Obesity and Diabetes in Youth (BODY) Project: description and feasibility of a program to halt obesity-associated disease among urban high school students

Type 2 diabetes (T2DM) and cardiovascular disease (CVD) are rising dramatically in adolescents in parallel with excess weight. The Banishing Obesity and Diabetes in Youth (BODY) Project, is a school-based intervention that medically screens overweight and obese high school students, provides personalized feedback, and connects to appropriate healthcare. Body mass index (BMI) was determined for 1,526 students in one New York City public high school with a school-based health center (SBHC). Overweight and obese students (n = 640) were invited to complete a medical evaluation that included a survey, blood pressure and blood tests. 328/640 (51%) eligible students returned signed parental consent and participated. All participants received a personalized report detailing their results along with specific recommendations on how to improve their health. Parents of participants with results outside healthy ranges (82%; 270/328) were called and mailed referral letters to connect with healthcare services. Project staff reached by telephone 74% (199/270) of those families and 29% (58/199) stated that the report led them to make arrangements to see a healthcare provider. Most students (83%; 273/328) were registered at the SBHC, and we shared their medical results with them so they could follow-up with the students. The BODY Project is a feasible program for urban schools with a SBHC. This may allow effective prevention of T2DM, and CVD from dyslipidemia and hypertension.

Physiological hepatic nuclear vacuolation--how long does it persist?

AIMS

Nuclear vacuolation/glycogenation is a characteristic histological feature of non-alcoholic fatty liver disease (NAFLD) that can help distinguish it from alcohol-induced liver disease. There are, however, other associations of nuclear vacuolation of which the commonest is as a normal feature of childhood. The aim of this study was to identify how long this physiological nuclear vacuolation persists.

METHODS AND RESULTS

Liver biopsy specimens from 872 patients with chronic hepatitis B virus infection (a condition known not to be associated with nuclear vacuolation) were studied to assess the frequency of nuclear vacuolation at different ages. All the patients studied had a body mass index of <25 kg/m(2) and an alcohol intake of <15 units/week, as well as no other risk factors for liver disease. It was found that the frequency of nuclear vacuolation, in the absence of NAFLD, fell from 13% at age 20-24 years to 4% in the early 30s and to 0% at age 60-64 years.

CONCLUSIONS

Physiological hepatic nuclear vacuolation is common in the 20s and persists into the 30s. This knowledge can help in the assessment of liver biopsy specimens in which nuclear vacuolation is a feature.

Skin capillary density and microvascular reactivity in obese subjects with and without metabolic syndrome

Obesity is associated with increased cardiovascular morbidity and mortality. We hypothesized that microvascular function may be impaired in obese subjects with metabolic syndrome (OB-MetSnd) compared to obese subjects without MetSnd (OB) and healthy subjects (HS). In this cross-sectional study, we evaluated skin capillary density (SCD) in OB-MetSnd (n=20, 12 women, BMI=36.5±1.1kg/m(2)), OB (n=25, 16 women, BMI=34.5±0.7kg/m(2)), and HS (n=30, 22 women, BMI=22.8±0.3kg/m(2)) groups. SCD was evaluated by intravital video-microscopy at rest and after post-occlusive reactive hyperemia (PORH) and venous congestion (VC). OB-MetSnd subjects exhibited significant differences in the values of MetSnd components and in leptin and HOMA-IR levels compared to OB and HS individuals. There were no differences in SCD among groups in resting conditions. The OB-MetSnd group failed to show a significant increase in the number of recruited capillaries during PORH and VC compared to the SCD evaluated at rest. A negative correlation of SCD with waist circumference, BMI, blood pressure, and HOMA-IR was observed after PORH and VC. When obese subjects were analyzed according to their HOMA-IR quartiles, a significant decrease in SCD was observed during POHR (P=0.02). Our findings showed that obese subjects have structural and functional alterations in skin microcirculation that are proportional to the increase in the degree of global and central obesity. In addition, in OB-MetSnd subjects, the cutaneous capillaries at rest are already maximally recruited, indicating an absence of functional capillary reserve. This may be related to the insulin resistance observed in OB-MetSnd individuals.

Metformin 2,500 mg/day in the treatment of obese women with polycystic ovary syndrome and its effect on weight, hormones, and lipid profile

PURPOSE

The objective of this study was to assess the efficacy and safety of metformin at the dosage of 2,500 mg/day in the treatment of obese women with PCOS and also to evaluate its effect on weight, hormones, and lipid profile.

METHOD

This study was a 4-month open-label clinical trial. Sixty-nine PCOS patients aged 20-35 were recruited in the study. Testosterone, free testosterone, sex hormone-binding globulin (SHBG), fasting insulin, dehydroepiandrostenedione-sulphate (DHEAS), FBS, LDH, HDL, TG, total cholesterol, body mass index (BMI), and waist-to-hip ratio were measured before treatment and after 4 months of treatment.

RESULTS

Significant reductions in serum insulin, BMI, waist/hip ratio, and LDL were observed. In addition, a significant increase in SHBG was obtained. Over the 4 months of the trial, 12 patients faced nausea, six patients had bloating, five patients had diarrhea and two had headache; none of these symptoms were severe except for two cases that dropped out due to severe vomiting.

CONCLUSION

The results of this study show that 2,500 mg daily dose of metformin in obese patients with PCOS is effective in the reduction of BMI, waist hip/ratio, LDL, serum insulin and increases SHBG. In general this dose was relatively safe and well tolerated.

Macrovascular and microvascular dysfunction in the metabolic syndrome

The metabolic syndrome (MetS) is associated with increased risk of type-2 diabetes and cardiovascular disease (CVD). We hypothesized that both small and large arteries may be impaired in subjects with the MetS, even in the absence of known CVD or diabetes. We compared both skin capillary density (CD) and pulse-wave velocity (PWV) in 36 cases with the MetS with those from 108 age- and gender-matched controls from the SU.VIM.AX-2 cohort. Compared with controls, MetS subjects demonstrated increased PWV (12.2+/-2.8 vs. 10.7+/-1.9 m s(-1), P=0.005) and lower functional CD (83.1+/-15.7 vs. 89.4+/-14.2 capillaries per mm(2), P=0.03). Functional CD was inversely related to fasting glucose, triglycerides (TGs) and HOMA-IR (all P<0.05). On the other hand, no association was found between CD and BP or with PWV. In multivariate models, the odds ratios (95% confidence interval) for one standard deviation change, for having an impaired PWV (>or=12 m s(-1), n=44), were: 1.65 (1.11-2.45) for systolic BP and 1.93 (1.25-2.99) for TG only. For impaired CD (<or=80 capillaries per mm(2)), the odds ratios (95% confidence interval) were 1.45 (1.00-2.08) for TG and 1.65 (1.13-2.43) for fasting glucose, only. In conclusion, MetS subjects exhibited evidence of macro- and microcirculatory dysfunction, even in the absence of diabetes and CVD. The common mechanism linking MetS components to CVD risk through small- and large-artery dysfunctions may be mediated through metabolic factors related to insulin resistance, not to increased BP.

Targeted disruption of carcinoembryonic antigen-related cell adhesion molecule 1 promotes diet-induced hepatic steatosis and insulin resistance

Carcinoembryonic antigen-related cell adhesion molecule 1 (CC1) is a cell adhesion molecule within the Ig superfamily. The Tyr-phosphorylated isoform of CC1 (CC1-L) plays an important metabolic role in the regulation of hepatic insulin clearance. In this report, we show that CC1-deficient (Cc1(-/-)) mice are prone to hepatic steatosis, as revealed by significantly elevated hepatic triglyceride and both total and esterified cholesterol levels compared with age-matched wild-type controls. Cc1(-/-) mice were also predisposed to lipid-induced hepatic steatosis and dysfunction as indicated by their greater susceptibility to store lipids and express elevated levels of enzymatic markers of liver damage after chronic feeding of a high-fat diet. Hepatic steatosis in the Cc1(-/-) mice was linked to a significant increase in the expression of key lipogenic (fatty acid synthase, acetyl CoA carboxylase) and cholesterol synthetic (3-hydroxy-3-methylglutaryl-coenzyme A reductase) enzymes under the control of sterol regulatory element binding proteins-1c and -2 transcription factors. Cc1(-/-) mice also exhibited impaired insulin clearance, glucose intolerance, liver insulin resistance, and elevated hepatic expression of the key gluconeogenic transcriptional activators peroxisome proliferator-activated receptor-gamma coactivator-1 and Forkhead box O1. Lack of CC1 also exacerbated both glucose intolerance and hepatic insulin resistance induced by high-fat feeding, but insulin clearance was not further deteriorated in the high-fat-fed Cc1(-/-) mice. In conclusion, our data indicate that CC1 is a key regulator of hepatic lipogenesis and that Cc1(-/-) mice are predisposed to liver steatosis, leading to hepatic insulin resistance and liver damage, particularly when chronically exposed to dietary fat.

Factors determining inadequate hypoglycaemia during insulin tolerance testing (ITT) after pituitary surgery

BACKGROUND

Some patients fail to achieve adequate hypoglycaemia following a standard dose of intravenous insulin during the insulin tolerance test (ITT). Persistent acromegaly or Cushing's disease may contribute to inadequate hypoglycaemia. Aim To identify factors that predict failure to achieve adequate hypoglycaemia during an ITT after pituitary surgery.

METHODS

We reviewed consecutive ITTs performed over a 10-year period in 76 patients following pituitary surgery. Analyses were performed to determine if body mass index (BMI), fasting blood glucose (FBG), cortisol, GH status or underlying diagnosis influenced the outcome.

RESULTS

Adequate hypoglycaemia (blood glucose < 2.2 mmol/l) was not achieved in 33 patients (Group 1) following a standard dose of neutral insulin (0.1 units/kg); 43 patients (Group 2) achieved adequate hypoglycaemia. Group 1 had significantly higher BMI, FBG, baseline cortisol and peak cortisol concentrations than Group 2. Peak GH response was not different. Multiple regression analysis showed that FBG was the only independent predictor of adequate hypoglycaemia. An insulin dose of 0.2 units/kg achieved adequate hypoglycaemia in 80% of patients with FBG >or= 5.5 mmol/l. In patients with acromegaly or Cushing's disease, failure to achieve adequate hypoglycaemia was associated with persistent disease.

CONCLUSION

FBG is an important determinant of the dose of insulin required to achieve adequate hypoglycaemia during an ITT in patients after pituitary surgery. A standard insulin dose of 0.1 U/kg is insufficient for adequate hypoglycaemia in patients with FBG > 5.5 mmol/l. Adequate response to a standard dose of insulin suggests a likelihood of cure of acromegaly or Cushing's disease after pituitary surgery.

Insulin sensitizers for women with polycystic ovarian syndrome

Polycystic ovarian syndrome (PCOS) is the most frequent endocrine disorder and most common cause of anovulation in women of reproductive age. It is a heterogeneous disorder, characterized by excess androgen, ovulatory dysfunction and/or polycystic ovaries. The syndrome is known for its association with several reproductive problems, including infertility and obstetric adverse effects. In addition, significant long-term health problems have been strongly linked to PCOS, with women suffering from the disorder having a significantly higher risk of diabetes, cardiovascular risk and some types of cancer, such as endometrial cancer. Although its etiology is unknown, insulin resistance is believed to play a pivotal role in its pathophysiology, with insulin sensitizers found to provide an exciting option in managing health problems associated with PCOS. Almost a decade ago, we proposed a non-insulin-sensitizing mechanism of action for insulin sensitizers through their effect on steroidogenesis. Accumulating evidence supported such an assumption, with solid evidence for a modulating effect on steroidogenesis by metformin and glitazones in the ovaries, adrenal glands and fat cells. Furthermore, other exciting positive roles for insulin sensitizers, in particular glitazones, have been reported at the level of endothelial function. Studying the value of insulin sensitizers in preventing long-term health problems in women with PCOS is still in the stage of infancy.

A novel single nucleotide polymorphism of INSR gene for polycystic ovary syndrome

OBJECTIVE

To investigate several single nucleotide polymorphisms (SNPs) in the insulin receptor (INSR) gene that have significant associations with pathogenesis of polycystic ovary syndrome (PCOS) in a Korean population.

DESIGN

Case-control study.

SETTING

University-based hospital.

PATIENT(S)

134 patients with PCOS and 100 healthy women as controls.

INTERVENTION(S)

All exons of INSR in DNA samples from 100 healthy women and 134 women with PCOS were sequenced and compared.

MAIN OUTCOME MEASURE(S)

Frequencies of genotypes for several SNPs in INSR gene that were found as specifically expressed SNPs in a Korean population.

RESULT(S)

Among nine SNPs analyzed in a large population, the genotypic frequencies of eight SNPs were similar, and they had no statistically significant association with PCOS. However, the frequency of a minor allele for one novel SNP, +176477 C>T, was higher in the control group than the patient group.

CONCLUSION(S)

Among the analyzed SNPs, +176477 C>T, a novel SNP in the INSR gene, was associated with the pathogenesis of PCOS in a Korean population.

Critical care issues in the patient after major joint replacement

Admission rates of orthopedic patients to intensive care units are increasing. Thus, an intensivist's familiarity with specific problems associated with major joint replacement surgery is of utmost importance in order to meet the needs of this particular patient population. In this article, the authors review the most commonly encountered complications after major hip and knee arthroplasty. Perioperative risk factors for morbidity and mortality and the epidemiology, diagnosis, and treatment of cardiopulmonary complications in this patient population are discussed. Procedure-specific complications such as fat embolism and acrylic bone cement-related issues are reviewed.

Beneficial associations of physical activity with 2-h but not fasting blood glucose in Australian adults: the AusDiab study

OBJECTIVE

We examined the associations of physical activity with fasting plasma glucose (FPG) and with 2-h postload plasma glucose (2-h PG) in men and women with low, moderate, and high waist circumference.

RESEARCH DESIGN AND METHODS

The Australian Diabetes, Obesity and Lifestyle (AusDiab) study provided data on a population-based cross-sectional sample of 4,108 men and 5,106 women aged >or=25 years without known diabetes or health conditions that could affect physical activity. FPG and 2-h PG were obtained from an oral glucose tolerance test. Self-reported physical activity level was defined according to the current public health guidelines as active (>or=150 min/week across five or more sessions) or inactive (<150 min/week and/or less than five sessions). Sex-specific quintiles of physical activity time were used to ascertain dose response.

RESULTS

Being physically active and total physical activity time were independently and negatively associated with 2-h PG. When physical activity level was considered within each waist circumference category, 2-h PG was significantly lower in active high-waist circumference women (beta -0.30 [95% CI -0.59 to -0.01], P = 0.044) and active low-waist circumference men (beta -0.25 [-0.49 to -0.02], P = 0.036) compared with their inactive counterparts. Considered across physical activity and waist circumference categories, 2-h PG levels were not significantly different between active moderate-waist circumference participants and active low-waist circumference participants. Associations between physical activity and FPG were nonsignificant.

CONCLUSIONS

There are important differences between 2-h PG and FPG related to physical activity. It appears that 2-h PG is more sensitive to the beneficial effects of physical activity, and these benefits occur across the waist circumference spectrum.

Molecular mechanisms of insulin resistance and associated diseases

Insulin resistance is a state in which higher than normal concentrations of insulin are required for normal response. The most common underlying cause is central obesity, although primary insulin resistance in normal-weight individuals is also possible. Excess abdominal adipose tissue has been shown to release increased amounts of free fatty acids which directly affect insulin signalling, diminish glucose uptake in muscle, drive exaggerated triglyceride synthesis and induce gluconeogenesis in the liver. Other factors presumed to play the role in insulin resistance are tumour necrosis factor alpha, adiponectin, leptin, IL-6 and some other adipokines. Hyperinsulinaemia which accompanies insulin resistance may be implicated in the development of many pathological states, such as hypertension and hyperandrogenaemia. Insulin resistance underlies metabolic syndrome and is further associated with polycystic ovary syndrome and lipodystrophies. When beta-cells fail to secrete the excess insulin needed, diabetes mellitus type 2 emerges, which is, besides coronary heart disease, the main complication of insulin resistance and associated diseases.

Leptin and insulin response to long-term total parenteral nutrition depends on body fat mass

BACKGROUND & AIMS

Circulating leptin and insulin concentrations are physiologically representing energy homeostasis. However, the artificial situation of long-term total parenteral nutrition (TPN) and its effects on serum leptin and insulin is not fully understood.

METHODS

We studied 42 gastroenterological patients who received TPN for 19+/-11 days. Serum leptin and insulin levels as well as body composition assessed by bioelectrical impedance analysis were evaluated on days 0, 7 and 14. Insulin sensitivity was estimated by calculating the QUICKI.

RESULTS

Before the start of TPN, leptin correlated positively with female gender (P<0.03), BMI (P<0.02), fat mass (P<0.02), insulin levels (P<0.001) and QUICKI (P<0.001). Within the first week of TPN, an increase of leptin levels was found only in patients with a body fat mass of >30% (P<0.02). As these were predominantly women, their leptin levels increased likewise (P<0.003). In regression analysis, fat mass (P<0.001), female gender (P<0.04), insulin levels (P<0.03), and i.v. glucose supply rates (P<0.05) were independently associated to leptin levels.

CONCLUSIONS

TPN-especially glucose-induces a neurohumoral response as shown here for leptin and insulin that is mainly depending on the fat mass. Better understanding of this regulatory mechanism during artificial nutrition could offer a new approach to improve its therapeutic effects.

Adipokines: implications for female fertility and obesity

Obesity is associated with a diverse set of metabolic disorders, and has reproductive consequences that are complex and not well understood. The adipose tissue-produced leptin has dominated the literature with regards to female fertility complications, but it is pertinent to explore the likely role of other adipokines--adiponectin and resistin--as our understanding of their biological functions emerge. Leptin influences the developing embryo, the functioning of the ovary and the endometrium, interacts with the release and activity of gonadotrophins and the hormones that control their synthesis. In this review such biological actions and potential roles of the adipokines leptin, adiponectin and resistin are explored in relation to female fertility and the complexity of the obese metabolic state.