Obesity, adipocyte hypertrophy, fasting glucose, and resistin are potential contributors to nonalcoholic fatty liver disease in South Asian women

The association between visceral adipocyte hypertrophy and NAFLD in subjects with different degrees of adiposity

OBJECTIVE

To investigate the association between visceral adipocyte hypertrophy and the onset and development of non-alcoholic fatty liver disease (NAFLD) in subjects with different degrees of adiposity.

METHODS

Omental adipose tissue and liver biopsies were collected from obese subjects. NAFLD was defined according to the NASH Clinical Research Network scoring system. Adipocyte size was measured using pathological section analysis. Adipose tissue insulin resistance (Adipo-IR) was calculated as fasting insulin (pmol/L) × fasting free fatty acid concentration (mmol/L).

RESULTS

In total, 275 obese patients were enrolled, including 158 females and 58 males with NAFLD. In females, adipocyte size was significantly larger in NAFLD participants as compared to the controls (99.37 ± 14.18 vs. 84.14 ± 12.65 [Formula: see text]m, p < 0.001). Moreover, adipocyte size was larger in females with non-alcoholic steatohepatitis (NASH) as compared to those with non-alcoholic fatty liver (NAFL) (101.45 ± 12.77 vs. 95.79 ± 15.80 [Formula: see text]m, p = 0.015). Mediation analysis showed that adipocyte size impacted the NAFLD activity score through Adipo-IR (b = 0.007 [95% bootstrap CI 0.002, 0.013]). Furthermore, the females were divided into: Q1 (BMI < 32.5 kg/m²), Q2 (BMI 32.5-35.5 kg/m²), Q3 (BMI 35.5-38.8 kg/m²) and Q4 (BMI ≥ 38.8 kg/m²) according to BMI quartiles. Omental adipocyte size was larger in NAFLD subjects in Q1-Q3, but not in Q4. No similar results were observed in males.

CONCLUSION

For the first time, we reported that visceral adipocyte hypertrophy was associated with the onset and progression of NAFLD in mild to moderate adiposity but not in severe obesity, which may be mediated by adipose tissue insulin resistance.

The Beneficial Additive Effect of Silymarin in Metformin Therapy of Liver Steatosis in a Pre-Diabetic Model

The combination of plant-derived compounds with anti-diabetic agents to manage hepatic steatosis closely associated with diabetes mellitus may be a new therapeutic approach. Silymarin, a complex of bioactive substances extracted from Silybum marianum, evinces an antioxidative, anti-inflammatory, and hepatoprotective activity. In this study, we investigated whether metformin (300 mg/kg/day for four weeks) supplemented with micronized silymarin (600 mg/kg/day) would be effective in mitigating fatty liver disturbances in a pre-diabetic model with dyslipidemia. Compared with metformin monotherapy, the metformin-silymarin combination reduced the content of neutral lipids (TAGs) and lipotoxic intermediates (DAGs). Hepatic gene expression of enzymes and transcription factors involved in lipogenesis (Scd-1, Srebp1, Pparγ, and Nr1h) and fatty acid oxidation (Pparα) were positively affected, with hepatic lipid accumulation reducing as a result. Combination therapy also positively influenced arachidonic acid metabolism, including its metabolites (14,15-EET and 20-HETE), mitigating inflammation and oxidative stress. Changes in the gene expression of cytochrome P450 enzymes, particularly Cyp4A, can improve hepatic lipid metabolism and moderate inflammation. All these effects play a significant role in ameliorating insulin resistance, a principal background of liver steatosis closely linked to T2DM. The additive effect of silymarin in metformin therapy can mitigate fatty liver development in the pre-diabetic state and before the onset of diabetes.

Managing cardiovascular disease risk in South Asian kidney transplant recipients

South Asians (SA) are at higher cardiovascular risk than other ethnic groups, and SA kidney transplant recipients (SA KTR) are no exception. SA KTR experience increased major adverse cardiovascular events both early and late post-transplantation. Cardiovascular risk management should therefore begin well before transplantation. SA candidates may require aggressive screening for pre-transplant cardiovascular disease (CVD) due to their ethnicity and comorbidities. Recording SA ethnicity during the pre-transplant evaluation may enable programs to better assess cardiovascular risk, thus allowing for earlier targeted peri- and post-transplant intervention to improve cardiovascular outcomes. Diabetes remains the most prominent post-transplant cardiovascular risk factor in SA KTR. Diabetes also clusters with other metabolic syndrome components including lower high-density lipoprotein cholesterol, higher triglycerides, hypertension, and central obesity in this population. Dyslipidemia, metabolic syndrome, and obesity are all significant CVD risk factors in SA KTR, and contribute to increased insulin resistance. Novel biomarkers such as adiponectin, apolipoprotein B, and lipoprotein (a) may be especially important to study in SA KTR. Focused interventions to improve health behaviors involving diet and exercise may especially benefit SA KTR. However, there are few interventional clinical trials specific to the SA population, and none are specific to SA KTR. In all cases, understanding the nuances of managing SA KTR as a distinct post-transplant group, while still screening for and managing each CVD risk factor individually in all patients may help improve the long-term success of all kidney transplant programs catering to multi-ethnic populations.

Tuina for diabetes with obesity: Protocol for a systematic review and meta-analysis

BACKGROUND

Obesity is an independent risk factor for the occurrence and development of diabetes. Patients with diabetes combined with obesity will face serious burdens such as increase in insulin resistance and difficulty in blood glucose control. As a safe, effective, economical, and simple intervention, Tuina is more acceptable to the public than drugs. The objective of this systematic evaluation and meta-analysis is to evaluate the efficacy and safety of Tuina for diabetes with obesity.

METHODS

We will search the following electronic databases: PubMed, Embase, Cochrane Library, Web of science, Chinese National Knowledge Infrastructure (CNKI), Sino Med, Wanfang, Chinese Clinical Trial Registry System, China Biomedical Literature Database (CBM). The time limit for retrieving studies is from establishment to November 2020 for each database. Randomized controlled clinical trials related to Tuina intervention on diabetes with obesity will be included. Data synthesis, sensitivity analysis, subgroup analysis as well as the assessment of bias risk will be conducted by using Stata V.13.0 and Review manager 5.3 software.

RESULTS

This study will provide a quantitative and standardized evaluation for the efficacy of Tuina therapy on diabetes with obesity.

CONCLUSION

This systematic review and meta-analysis will provide the high-quality evidence of whether Tuina is an effective intervention for diabetes with obesity.

REGISTRATION NUMBER

INPLASY2020110106.

Investigating the Relationship Between Insulin Resistance and Fatty Liver in a Random Population of Tehran

Background: Insulin resistance can be a predictor of adverse fatty liver disease and health problems. Objectives: The present study aimed to investigate the effect of insulin resistance on fatty liver disease. Methods: This study used the data of 2,160 individuals registered in a cross-sectional study who were randomly selected from among clients of a nutrition clinic in Tehran from April to December 2019. Insulin resistance and beta-cell activity were calculated by the homeostasis model assessment formula. The study outcome was defined as having fatty liver disease. The odds ratio (95% CI) was calculated using logistic regression models. Results: The mean age was 35 (± 9) in healthy subjects and 49 (± 8) in fatty liver disease patients (age range: 16 to 42 years). Nearly 34.5% of the individuals had fatty liver disease. According to the adjusted results of the logistic regression model, the risk of NAFLD was 1.05 (P < 0.001) for one unit increase in fasting insulin and 1.01 (P < 0.001) for one unit increase in 2-h insulin, which indicated the statistically significant relationship of NAFLD with fasting insulin and 2-h insulin. Also, the risk of NAFLD was 1.01 P < 0.001) for one unit increase in FPG, which was statistically significant. Moreover, the adjusted risk of NAFLD was 1.00 (P < 0.001) for one unit increase in 2-h glucose, which was not statistically significant. Finally, the adjusted risk of NAFLD was 1.29 (P < 0.001) for one unit increase in HOMA-IR, which was statistically significant. Conclusions: The findings of the present study demonstrated that insulin resistance could increase the risk of fatty liver disease. Also, each one-unit increase in fasting blood sugar, fasting insulin, and 2-h insulin increased the risk of fatty liver disease. Therefore, the results of this study may be useful for health policymakers to design suitable preventive and therapeutic interventions for those with NAFLD to prevent and control this disease.

Effects of Curcumin in a Mouse Model of Very High Fat Diet-Induced Obesity

Worldwide rates of Western-diet-induced obesity epidemics are growing dramatically. Being linked with numerous comorbidities and complications, including cardiovascular disease, type 2 diabetes, cancer, chronic inflammation, and osteoarthritis (OA), obesity represents one of the most threatening challenges for modern healthcare. Mouse models are an invaluable tool for investigating the effects of diets and their bioactive components against high fat diet (HFD)-induced obesity and its comorbidities. During recent years, very high fat diets (VHFDs), providing 58–60% kcal fat, have become a popular alternative to more traditional HFDs, providing 40–45% total kcal fat, due to the faster induction of obesity and stronger metabolic responses. This project aims to investigate if the 60% fat VHFD is suitable to evaluate the protective effects of curcumin in diet-induced obesity and osteoarthritis. B6 male mice, prone to diet-induced metabolic dysfunction, were supplemented with VHFD without or with curcumin for 13 weeks. Under these experimental conditions, feeding mice a VHFD for 13 weeks did not result in expected robust manifestations of the targeted pathophysiologic conditions. Supplementing the diet with curcumin, in turn, protected the animals against obesity without significant changes in white adipocyte size, glucose clearance, and knee cartilage integrity. Additional research is needed to optimize diet composition, curcumin dosage, and duration of dietary interventions to establish the VHFD-induced obesity for evaluating the effects of curcumin on metabolic dysfunctions related to obesity and osteoarthritis.

Association between fasting plasma glucose and nonalcoholic fatty liver disease in a nonobese Chinese population with normal blood lipid levels: a prospective cohort study

Background

Fasting plasma glucose (FPG) is an easily quantifiable and inexpensive metabolic marker, which is often used to assess cardiovascular disease and diabetes. However, there have been limited studies on the association between FPG and nonalcoholic fatty liver disease (NAFLD) risk in nonobese people, especially in Chinese individuals. The purpose of this study was to investigate the association between FPG and NAFLD in nonobese Chinese people with normal blood lipid levels.

Methods

In this prospective cohort study, 9767 nonobese participants with normal blood lipid levels without NAFLD were recruited and prospectively followed for 5 years. The Cox proportional hazard model was used to evaluate the risk factors of NAFLD. Moreover, a Cox model with cubic spline functions and smooth curve fitting (the cubic spline smoothing) were used to identify the nonlinear association between FPG and NAFLD.

Results

During the 5-year follow-up, 841 (8.61%) participants were diagnosed with NAFLD. The good functional results (without NAFLD) estimated by the Kaplan-Meier method for 1 year, 2 years, 3 years, 4 years, and 5 years were 98.84, 95.35, 91.67%, 87.57 and 74.86%, respectively. Additionally, through the Cox proportional hazard model, after adjusting for other covariates, there was an independent positive correlation between FPG and increased NAFLD risk (HR:1.21, 95% CI:1.15–1.28, P < 0.0001), and the NAFLD risk was incrementally higher with the rising FPG quartile. The nonlinear association between FPG and NAFLD was visualized by cubic spline smoothing technique. It was calculated that the inflection point of FPG was 5.54. When FPG ≤ 5.54, there was a positive correlation between FPG and the risk of NAFLD (HR:2.20, 95% CI:1.78–2.73, P < 0.0001). When FPG > 5.54, the risk of NAFLD increased by 50% (HR:1.10, 95% CI:1.02–1.18, P = 0.0159) compared with the left side of the inflection point and gradually leveled off.

Conclusions

In a nonobese Chinese population with normal lipid levels, there is an independent nonlinear association between FPG and NAFLD, and the increase in FPG may indicate an increased risk of NAFLD. Additionally, this independent association is more obvious in the short stature population.

Association between ratio of γ-glutamyl transpeptidase to high-density lipoprotein cholesterol and prevalence of nonalcoholic fatty liver disease and metabolic syndrome: a cross-sectional study

Background

Metabolic risk factors including obesity, insulin resistance, dyslipidemia, metabolic syndrome (MS), and diabetes are associated with nonalcoholic fatty liver disease (NAFLD). γ-Glutamyl transpeptidase (GGT) and high-density lipoprotein cholesterol (HDL-C) are associated with insulin resistance, dyslipidemia, oxidative stress, and obesity. We investigated the associations between GGT/HDL-C ratio and prevalence of NAFLD in a Chinese population.

Methods

The study included 1,813 NAFLD (526 females, 1,287 males) and 4,513 non-NAFLD (3,077 females, 1,436 males) participants. The diagnosis of NAFLD was based on ultrasonography.

Results

Participants with NAFLD had higher GGT/HDL-C ratio, BMI, WC, TG, TC, and HOMA-IR, but lower HDL-C than participants without NAFLD. GGT/HDL-C ratio was significantly associated with prevalence of NAFLD. Specifically, for each 1 unit increase in GGT/HDL-C ratio, the prevalence of NAFLD will increase by 0.3%. As GGT/HDL-C ratio quartiles increased, prevalence of NAFLD/MS in Q4 (highest GGT/HDL-C ratio quartile) was 6.362/3.968 times higher than that in Q1 (lowest GGT/HDL-C ratio quartile). The AUC [0.799 (0.788-0.810)] for GGT/HDL-C ratio was significantly higher than those for GGT and HDL-C alone.

Conclusions

The present results suggest that GGT/HDL-C ratio can be used as a predictive factor for prevalence of NAFLD after adjustment for confounding variables.