Obesity is more closely related with hepatic steatosis and fibrosis measured by transient elastography than metabolic health status

Characteristics of the epicardial adipose tissue measured by low-dose chest computed tomography according to the metabolic health/obesity status

BACKGROUND

Epicardial adipose tissue (EAT) is associated with the development of cardiovascular disease and long-term survival. This study aimed to assess the characteristics of EAT according to the metabolic health and obesity status using low-dose chest computed tomography (CT).

METHODS

A total of 1074 asymptomatic adults who underwent a medical health check-up were enrolled. Subjects were categorized into the following four groups according to the metabolic health and obesity status: metabolically healthy non-obese (MHNO); metabolically unhealthy non-obese (MUNO); metabolically healthy obese (MHO); and metabolically unhealthy obese (MUO). EAT on low-dose chest CT was measured by using automatic, quantitative measurement software.

RESULTS

MUO showed the highest EAT volume and lowest EAT radiodensity in comparison with MHNO (p < 0.001). The MUNO (n = 70), MHO (n = 259), and MUO (n = 231) groups had increased EAT volume (β [95 % CI], 37.65 [23.11,52.18], 56.79 [47.56,66.02], 84.85 [74.59,95.11] respectively, all p < 0.001), decreased EAT radiodensity (β [95 % CI], - 3.22 [- 4.59,- 1.85], - 4.48 [- 5.30,- 3.66], - 6.03 [- 6.90,- 5.16] respectively, all p < 0.001) in comparison with the MHNO (n = 514) group by using multivariable linear regression models.

CONCLUSIONS

Both metabolic abnormalities and obesity were closely associated with EAT characteristics. Characteristics of EAT are similar in MHO and MUNO. This finding suggests that MHO is not a favorable condition in terms of cardiac health, as assessed by the characteristics of EAT. The combination of obesity and metabolically unhealthy status has a synergistic adverse effect on EAT. Measurement of EAT could be a useful imaging biomarker for evaluation of an individual's metabolic health/obesity status.

Decreased Hepatic and Serum Levels of IL-10 Concur with Increased Lobular Inflammation in Morbidly Obese Patients

Background and Objectives: Non-alcoholic fatty liver disease (NAFLD) is associated with obesity and ranges from simple steatosis to non-alcoholic steatohepatitis (NASH), fibrosis, cirrhosis, and hepatocellular carcinoma. Accumulating evidence in animal models suggests that loss of interleukin-10 (IL-10) anti-inflammatory actions might contribute to lobular inflammation, considered one of the first steps toward NASH development. However, the role of IL-10 in lobular inflammation remains poorly explored in humans. We examined mRNA and protein levels of IL-10 in liver biopsies and serum samples from morbidly obese patients, investigating the relationship between IL-10 and lobular inflammation degree. Materials and Methods: We prospectively enrolled morbidly obese patients of both sexes, assessing the lobular inflammation grade by the Brunt scoring system to categorize participants into mild (n = 7), moderate (n = 19), or severe (n = 13) lobular inflammation groups. We quantified the hepatic mRNA expression of IL-10 by quantitative polymerase chain reaction and protein IL-10 levels in liver and serum samples by Luminex Assay. We estimated statistical differences by one-way analysis of variance (ANOVA) and Tukey's multiple comparison test. Results: The hepatic expression of IL-10 significantly diminished in patients with severe lobular inflammation compared with the moderate lobular inflammation group (p = 0.01). The hepatic IL-10 protein levels decreased in patients with moderate or severe lobular inflammation compared with the mild lobular inflammation group (p = 0.008 and p = 0.0008, respectively). In circulation, IL-10 also significantly decreased in subjects with moderate or severe lobular inflammation compared with the mild lobular inflammation group (p = 0.005 and p < 0.0001, respectively). Conclusions: In liver biopsies and serum samples of morbidly obese patients, the protein levels of IL-10 progressively decrease as lobular inflammation increases, supporting the hypothesis that lobular inflammation develops because of the loss of the IL-10-mediated anti-inflammatory counterbalance.

Visceral and subcutaneous abdominal fat is associated with non-alcoholic fatty liver disease while augmenting Metabolic Syndrome's effect on non-alcoholic fatty liver disease: A cross-sectional study of NHANES 2017-2018

BACKGROUND

The aim was to evaluate the effect different types of abdominal fat have on NAFLD development and the effects of abdominal fat has on the association between Metabolic Syndrome (MetS) and NALFD.

METHODS

Data was collected from the cross-sectional NHANES dataset (2017-2018 cycle). Using the controlled attenuation parameter (USG CAP, dB/m), which measures the level of steatosis, the cohort was stratified into two groups: NAFLD(+) (≥274 dB/m) and NAFLD(-). Using complex samples analyses, associations between liver steatosis or NAFLD and types of abdominal fat area [Total abdominal (TAFA), subcutaneous (SAT), and visceral (VAT)] were determined. Pearson's correlation coefficient (r) was calculated to evaluate the associations between adipose tissues and NAFLD. Logistic regression was used to determine the risk [odds ratio (OR) and 95% confidence interval (95%CI)]. Participants were also classified by MetS, using the Harmonizing Definition criteria.

RESULTS

Using 1,980 participants (96,282,896 weighted), there was a significant (p<0.001) correlation between USG CAP and TAFA (r = 0.569), VAT (r = 0.645), and SAT (r = 0.479). Additionally, the risk of developing NAFLD was observed for total abdominal obesity (OR = 19.9, 95%CI: 5.1-77.8, p<0.001), visceral obesity (OR = 9.1, 95%CI: 6.2-13.5, p<0.001) and subcutaneous obesity (OR = 4.8, 95%CI: 3.2-6.9, p<0.001). Using 866 participants (44,399,696 weighted), for visceral obesity, participants with MetS and visceral obesity (OR = 18.1, 95%CI: 8.0-41.3, p<0.001) were shown to have a greater risk than participants with MetS only (OR = 6.3, 95%CI: 2.6-15.2, p<0.001). For subcutaneous obesity, again, participants with MetS and subcutaneous obesity (OR = 18.3, 95%CI: 8.0-41.9, p<0.001) were shown to have a greater risk than the MetS-only group (OR = 10.3, 95%CI: 4.8-22.4, p<0.001).

CONCLUSION

TAFA, VAT, and SAT were positively associated with USG CAP values and increased the risk of developing NAFLD. Also, the type of abdominal fat depots did affect the association between MetS and NAFLD.

Stretchable ultrasonic arrays for the three-dimensional mapping of the modulus of deep tissue

Serial assessment of the biomechanical properties of tissues can be used to aid the early detection and management of pathophysiological conditions, to track the evolution of lesions and to evaluate the progress of rehabilitation. However, current methods are invasive, can be used only for short-term measurements, or have insufficient penetration depth or spatial resolution. Here we describe a stretchable ultrasonic array for performing serial non-invasive elastographic measurements of tissues up to 4 cm beneath the skin at a spatial resolution of 0.5 mm. The array conforms to human skin and acoustically couples with it, allowing for accurate elastographic imaging, which we validated via magnetic resonance elastography. We used the device to map three-dimensional distributions of the Young's modulus of tissues ex vivo, to detect microstructural damage in the muscles of volunteers before the onset of soreness and to monitor the dynamic recovery process of muscle injuries during physiotherapies. The technology may facilitate the diagnosis and treatment of diseases affecting tissue biomechanics.

Insulin Resistance Is the Main Characteristic of Metabolically Unhealthy Obesity (MUO) Associated with NASH in Patients Undergoing Bariatric Surgery

(1) Background: Metabolically healthy obesity (MHO) is a concept that applies to obese patients without any elements of metabolic syndrome (metS). In turn, metabolically unhealthy obesity (MUO) defines the presence of elements of metS in obese patients. The components of MUO can be divided into subgroups regarding the elements of inflammation, lipid and glucose metabolism and cardiovascular disease. MUO patients appear to be at greater risk of developing non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) compared to MHO patients. The aim of this study was to evaluate the influence of different MUO components on NAFLD and NASH in patients with morbid obesity undergoing bariatric surgery. (2) Methods: 141 patients undergoing bariatric surgery from September 2015 and October 2021 at RWTH Aachen university hospital (Germany) were included. Patients were evaluated pre-operatively for characteristics of metS and MUO (HbA1c, HOMA, CRP, BMI, fasting glucose, LDL, TG, HDL and the presence of arterial hypertension). Intraoperatively, a liver biopsy was taken from the left liver lobe and evaluated for the presence of NAFLD or NASH. In ordinal regression analyses, different factors were evaluated for their influence on NAFLD and NASH. (3) Results: Mean BMI of the patients was 52.3 kg/m² (36-74.8, SD 8.4). Together, the parameters HbA1c, HOMA, CRP, BMI, fasting glucose, LDL, TG, HDL and the presence of arterial hypertension accounted for a significant amount of variance in the outcome, with a likelihood ratio of χ² (9) = 41.547, p < 0.001, for predicting the presence of NASH. Only HOMA was an independent predictor of NASH (B = 0.102, SE = 0.0373, p = 0.007). Evaluation of steatosis showed a similar trend (likelihood ratio χ² (9) = 40.272, p < 0.001). Independent predictors of steatosis were HbA1c (B = 0.833, SE = 0.343, p = 0.015) and HOMA (B = 0.136, SE = 0.039, p < 0.001). (4) Conclusions: The above-mentioned model, including components of MUO, was significant for diagnosing NASH in patients with morbid obesity undergoing bariatric surgery. Out of the different subitems, HOMA independently predicted the presence of NASH and steatosis, while HbA1c independently predicted steatosis and fibrosis. Taken together, the parameter of glucose metabolism appears to be more accurate for the prediction of NASH than the parameters of lipid metabolism, inflammation or the presence of cardiovascular disease.

Evaluation of Liver Metabolism Biomarkers in Metabolic Associated Fatty Liver Disease According to Obesity Phenotype

OBJECTIVE

To analyze the relationship between the biochemical markers of liver metabolism in different stages of Metabolic Associated Fatty Liver Disease (MAFLD) according to the obesity phenotype.

METHODOLOGY

This is a cross-sectional study with individuals with class III obesity classified according to the obesity phenotypes proposed by the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) criteria. Biochemical and anthropometric variables were analyzed according to the staging of MAFLD and obesity phenotype.

RESULTS

A total of 50 subjects with MAFLD, 62% (n = 31) with steatosis and 38% (n = 19) with steatohepatitis without fibrosis; 36% were classified as metabolically healthy obesity (MHO) and 64% as metabolically unhealthy obesity (MUHO), respectively. Mean values of alkaline phosphatase were 85.44 ± 27.27 vs. 61.92 ± 17.57 (p = 0.006); gamma-glutamyl transpeptidase, 25.77 ± 15.36 vs. 30.63 ± 19.49 (p = 0.025); and albumin, 3.99 ± 0.34 vs. 4.24 ± 0.23 (p = 0.037), were lower and statistically significant in the MHO group with steatosis. The results show when considering individuals with IR, only AP is a predictor of unhealthy phenotype (B-0.934, 0.848- 1.029, p = 0.031).

CONCLUSION

MHO individuals with steatosis present lower severe changes related to markers of liver damage and function and AP is considered the predictor of MUHO phenotype.

Chemical Profiles and Antiobesity Effect of a Mixture of Astragalus membranaceus and Lithospermum erythrorhizon Extract in High Fat Diet Fed Mice

The present study aimed to evaluate the antiobesity potential and synergistic effects of ALM16, a mixture of Astragalus membranaceus (AM) and Lithospermum erythrorhizon (LE) extracts, in HFD-induced obese mice. C57BL/6 mice were fed a normal diet (ND), high-fat diet (HFD), HFD + AM, HFD + LE or HFD + ALM16 (50, 100, and 200 mg/kg) daily for 5 weeks. Compared to the ND group, HFD-fed mice showed significant increases in body weight, food efficiency ratio, weights of white adipose tissues, adipocytes size, liver weight, and hepatic steatosis grade. However, ALM16 significantly reduced those increases induced by HFD. Moreover, as compared to the HFD group, the ALM16 group significantly ameliorated serum levels of lipid profiles (TG, TC, HDL, and LDL), adipokines (leptin and adiponectin), and liver damage markers (AST and ALT levels). Notably, ALM16 was more effective than AM or LE alone and had a similar or more potent effect than Garcinia cambogia extracts, as a positive control, at the same dose. These results demonstrate that ALM16 synergistically exerts anti-obesity effects based on complementary interactions between each component. Also, metabolic profiling between each extract and the ALM16 was confirmed by UPLC-QTOF/MS, and the difference was confirmed by relative quantification.

Liver Stiffness in Obese Hypothyroid Patients Taking Levothyroxine

Background and Objectives: Thyroid dysfunction is associated with non-alcoholic fatty liver disease, but its role in the progression of liver damage in obese patients remains unclear. In addition, several case reports have suggested the existence of a levothyroxine-induced liver injury, which has been poorly investigated. Our aim was to verify whether a difference in the prevalence of liver fibrosis exists in a population of obese individuals taking Levothyroxine. Materials and Methods: We conducted a cross-sectional study on a population of 137 obese individuals, of which 49 were on replacement therapy with Levothyroxine. We excluded those who had hypertriglyceridemia and diabetes mellitus. All participants underwent a liver stiffness assessment by transient elastography as well as biochemical measurements. In subjects with liver fibrosis, other cause of liver fibrosis were ruled out. Results: Participants taking Levothyroxine had a higher prevalence of liver fibrosis than those not taking Levothyroxine (30.6% vs. 2.3%; p < 0.001), and these results were obtained after we made an adjustment for age (Exp(B) = 18.9; 95% CI = 4.1−87.4; p < 0.001). The liver stiffness value differed significantly between groups (6.0 ± 3.6 and 5.1 ± 1.2, p = 0.033). Of those subjects taking Levothyroxine, there were no significant differences in the dose of medication (1.21 ± 0.36 vs. 1.07 ± 0.42; p = 0.240) and treatment duration (13.7 ± 7.43 vs. 11.13 ± 6.23; p = 0.380) between those with and without liver fibrosis. Conclusions: We found, for the first time, a greater prevalence of liver fibrosis in obese individuals taking Levothyroxine than in those not taking this medication. This finding needs to be confirmed by longitudinal population studies as well as by cellular studies.

A Noninvasive Scoring System for Liver Fibrosis in Patients With Metabolic Dysfunction-Associated Fatty Liver Disease

Background and Aims

Metabolic dysfunction-associated fatty liver disease (MAFLD) is diagnosed in patients with hepatic steatosis who meet at least one of the following criteria: body mass index >25, diabetes mellitus type 2, and metabolic dysfunction. Given about one-third of Americans meet the criteria for MAFLD, there is an unmet need for a score to noninvasively triage patients who need transient elastography and possible biopsy. We determined the risk factors for advanced fibrosis (F3+ on transient elastography) in a cohort of 2671 MAFLD patients and developed the MAFLD fibrosis-4 (FIB-4) score to help clinicians predict the risk of advanced fibrosis.

Methods

Multivariate logistic regression analysis and independent t-tests were used to evaluate the relationship between physical exam parameters, lab values, and interview responses and risk of advanced fibrosis. The most significant risk factors were used to build the MAFLD FIB-4 score, equivalent to -46.55 + (7.89∗log[waist circumference]) + (1.25∗log[fasting plasma glucose]) + (0.85∗FIB-4 score).

Results

Risk factors for advanced fibrosis in MAFLD patients are elevated body mass index (odds ratio [OR] = 5.90; P < .01), waist circumference (OR = 3.53; P < .01), high fasting plasma glucose (OR = 2.45; P < .01), high homeostasis model assessment-estimated insulin resistance score (OR = 2.18; P = .02), high triglycerides (OR = 1.94; P = .03), positive hepatitis C RNA (OR = 14.92; P = .02), high ferritin (OR = 1.58; P = .05), and alanine transaminase > aspartate aminotransferase (OR = 1.54; P = .04). The MAFLD FIB-4 score has a specificity of 80%, sensitivity of 97%, and receiver operating characteristic of 0.85 (compared to the receiver operating characteristic of 0.60 for FIB-4 and 0.68 for nonalcoholic fatty liver disease existing scores) for the detection of advanced fibrosis in MAFLD patients.

Conclusion

Clinicians can utilize the MAFLD FIB-4 score to noninvasively identify patients with advanced fibrosis risk for further evaluation and management.

Obesity is an important determinant of severity in newly defined metabolic dysfunction-associated fatty liver disease

BACKGROUND

The recently proposed definition of metabolic dysfunction-associated fatty liver disease (MAFLD) is based on the co-existence of hepatic steatosis with other metabolic disorders, including obesity and metabolic risk abnormalities such as hyperglycemia, high blood pressure and dyslipidemia. This study aimed to assess MAFLD severity according to the presence of metabolic abnormalities and obesity.

METHODS

Using transient elastography, hepatic steatosis and fibrosis severity were assessed by measuring the controlled attenuation parameter and liver stiffness measurement. A total of 1163 patients with MAFLD were categorized into the following four groups according to metabolic risk abnormalities and obesity presence: non-obese without metabolic risk abnormality group (Group 1; reference group); non-obese with metabolic risk abnormality group (Group 2); obese without metabolic risk abnormality group (Group 3); and obese with metabolic risk abnormality group (Group 4). A multiple logistic regression analysis was performed to determine severe hepatic steatosis and fibrosis risk in each group in both unadjusted and adjusted models.

RESULTS

In the adjusted model, the odds ratios (ORs) [95% confidence interval (CI)] for severe hepatic steatosis in Groups 2, 3, and 4 were 1.07 (0.61-1.88), 2.43 (1.44-4.08), and 4.07 (2.56-6.48), respectively (P_trend < 0.001). For liver fibrosis, compared with Group 1, Group 2 showed no significant increases in OR, whereas Groups 3 and 4 (obese groups) showed significant increases (OR = 4.70, 95% CI: 1.24-17.82 and OR = 6.43, 95% CI: 1.88-22.02, respectively).

CONCLUSIONS

Obesity, rather than metabolic abnormality, is the principal determinant of severe hepatic steatosis and fibrosis in patients with MAFLD.

Polycystic Ovary Syndrome and Metabolic Syndrome: Clinical and Laboratory Findings and Non-Alcoholic Fatty Liver Disease Assessed by Elastography

OBJECTIVE

 To evaluate the association between polycystic ovary syndrome (PCOS) and metabolic syndrome (MetS), adding liver assessment through elastography and ultrasound, for correlation with non-alcoholic fatty liver disease (NAFLD). Metabolic syndrome occurs in ∼ 43% of women with PCOS, and NAFLD is the hepatic expression of MetS.

METHODS

 One hundred women, 50 with PCOS and 50 controls, matched by age (18-35 years) and body mass index (BMI) were included, restricted to patients with overweight and obesity grade 1, at the Assis Chateaubrian Maternity School, Universidade Federal do Ceará, Brazil. For the diagnosis of PCOS, we adopted the Rotterdam criteria, and for the diagnosis of MetS, the criteria of the National Cholesterol Education Program (NCEP/ATP III). Hepatic elastography and ultrasound were performed to assess liver stiffness and echotexture, respectively.

RESULTS

 The average ages were 29.1 (±5.3) and 30.54 (±4.39) years, for the PCOS and the control group, respectively. Patients with PCOS had a risk 4 times higher of having MetS, odds ratio (95% confidence interval) = 4.14, than those in the control group. Women with PCOS had higher average of abdominal circumference (100.9 ± 9.08 cm vs 94.96 ± 6.99 cm) and triglycerides (162 ± 54.63 mg/dL vs 137.54 ± 36.91 mg/dL) and lower average of HDL cholesterol (45.66 ± 6.88 mg/dL vs 49.78 ± 7.05 mg/dL), with statistically significant difference. Hepatic steatosis was observed on ultrasound in women with PCOS; however, with no statistically significant difference. There was no change to NAFLD at elastography in any group.

CONCLUSION

 Women with PCOS had 4-fold higher frequency of MetS and more hepatic steatosis, with no statistically significant difference. There was no change in liver stiffness between the groups at elastography. The results can be extended only to populations of overweight and obesity grade 1, with PCOS or not. They cannot be generalized to other untested groups.

The impact of metabolic health on non-alcoholic fatty liver disease (NAFLD). A single center experience

BACKGROUND

The role of patients' metabolic clinical and biochemical profile in NAFLD has not been extensively explored.

AIMS

The aim of the study was to assess the role of metabolic health in NAFLD patients and to examine liver disease progression in these populations.

METHODS

The medical charts of 569 patients diagnosed with fatty liver were thoroughly reviewed; 344 patients were excluded because of other chronic liver diseases. Metabolically healthy people were defined as those who met none of the following criteria: blood pressure ≥ 130/85 mmHg or under hypertension treatment, fasting glucose ≥ 100 mg/dl or under diabetes treatment, serum triglycerides > 150 mg/dl, high density lipoprotein-cholesterol <40/50 mg/dl for men/women. Study participants were followed-up over a median period of 22 months.

RESULTS

The present observational case-control study included 225 NAFLD patients; 14 (6.2%) were metabolically healthy. Metabolically healthy participants were younger (p = 0.006), had lower age at diagnosis (p = 0.002), lower levels of γ-GT (p = 0.013), fasting glucose (p <0.001) and triglycerides (p <0.001) and higher HDL-cholesterol (p = 0.005) compared to metabolically non-healthy. By the last follow up assessment, 8 metabolically healthy patients had developed dyslipidemia; 1 patient (14.4%) had presented liver disease progression compared to 8 patients (10.5%) from the unhealthy group (p = 0.567). In multivariate analysis, diabetes mellitus (p = 0.017) and hemoglobin levels (p = 0.009) were the sole independent predictors of disease progression. No significant difference was observed in liver disease progression-free survival rates among the two patient groups (p = 0.503).

CONCLUSIONS

Metabolically healthy NAFLD patients presented with a favorable biochemical profile; however, they were diagnosed with NAFLD at a younger age and the liver disease progression risk was similar to that of metabolically unhealthy patients. These findings suggest that metabolically healthy NAFLD may not constitute a benign condition and patients could potentially be at increased risk of metabolic syndrome and liver disease progression.

The Perirenal Fat Thickness Was Associated with Nonalcoholic Fatty Liver Disease in Patients with Type 2 Diabetes Mellitus

PURPOSE

Obesity is an important risk factor for nonalcoholic fatty liver disease (NAFLD). Perirenal fat and paranephric fat were seldom studied in NAFLD. We aimed to explore the relationship between perirenal fat thickness (PrFT) and paranephric fat thickness (PnFT) and NAFLD in patients with type 2 diabetes mellitus (T2DM).

PATIENTS AND METHODS

A total of 493 diabetic patients including 231 NAFLD patients were enrolled in our study from September 2019 to December 2020. Patients with NAFLD were categorized into three subgroups according to the severity and fibrosis risk of NAFLD. Anthropometric indices and clinical characteristics were collected from clinical records. PrFT and PnFT were measured via ultrasound. Multivariate logistic regression analysis was used to assess the association between PrFT, PnFT and presence, severity and advanced fibrosis risk of NAFLD.

RESULTS

Compared with non-NAFLD patients, those with NAFLD had significantly higher PrFT and PnFT. The PrFT and PnFT were independently associated with presence of NAFLD and the PrFT was independently associated with the advanced fibrosis risk of NAFLD after adjusting confounding factors.

CONCLUSION

The PrFT was independently associated with the presence and advanced fibrosis risk of NAFLD in patients with T2DM.

Potential metabolic activities of raspberry ketone

Novel food and food compounds interventions have attracted a lot of attention nowadays for the prevention and treatment of metabolic diseases. Raspberry ketone (RK) is aromatic compound found within red fruits and berries, has been used as an over-the-counter product for weight loss. However, actually, the effect of RK on weight loss is still controversial, and the mechanism is largely unknown. Besides, in vivo and in vitro studies have demonstrated the beneficial effect of RK on the development of other metabolic diseases. In this review, we comprehensively highlighted the synthesis, bioavailability, and metabolism of RK, and summarized the progress made in our understanding of the potential biological activities of RK, including antiobesity, antidiabetes, cardioprotection, and hepatoprotection, as well as their underlying mechanisms. This paper provides a critical overview about the current findings and proposes the future studies in the area of RK on human health. PRACTICAL APPLICATIONS: Raspberry ketone (RK) has been used for weight control for years, but this effect is controversial considering food intake. Additionally, RK is beneficial for T2DM, liver and heart injury. The underlying mechanisms of the protective effect of RK including accelerating fatty acid oxidation, balancing serum glucose level, anti-inflammation, antioxidant process, and so on. In this context, we provide a comprehensive analysis of the benefits of RK against many metabolic diseases and discuss the underlying molecular mechanisms. We hope our work will be helpful for further researches on RK and improve its public recognition.

Metabolically healthy and unhealthy obesity and the progression of liver fibrosis: A cross-sectional study

BACKGROUND

The development of liver fibrosis is the most important predictor of adverse outcomes in patients with non-alcoholic fatty liver disease (NAFLD). Little is known regarding the risk factors for the progression of NAFLD to liver fibrosis. The present cross-sectional study aimed to examine the association of liver fibrosis with metabolically healthy and unhealthy obesity among patients with NAFLD.

METHODS

The severity of fatty liver was examined using ultrasonography. We used the NAFLD fibrosis score to determine the severity of liver fibrosis. Anthropometric indices, physical activity, and body composition were assessed. Blood samples were collected to determine serum metabolic parameters. Participants without any component of metabolic syndrome and homeostasis model assessment of insulin resistance (HOMA-IR) <2.5 were considered as metabolically healthy. To examine the association of liver fibrosis with metabolically healthy and unhealthy obesity, multivariable-adjusted odds ratios (ORs) were applied.

RESULTS

The current study included a total of 246 patients with NAFLD and low probability of fibrosis. 46.3% of subjects were metabolically healthy and 53.7% were metabolically unhealthy. Among metabolically healthy subjects, multivariable-adjusted ORs (CIs) for worsening of NAFLD fibrosis score comparing body mass indexes (BMIs) 23.0-24.9, 25-29.9, and ≥30 with a BMI=18.5-22.9 kg/m² were 1.28 (1.09-1.56), 1.99 (1.49-2.63), and 3.96 (2.89-4.71), respectively. The corresponding ORs (95% CIs) among metabolically unhealthy subjects were 1.39 (1.32-1.64), 2.27 (1.98-2.49), and 4.11 (3.12-4.93), respectively. Moreover, in both healthy and unhealthy individuals, higher percentages of body fat and waist circumference were significantly associated with worsening of NAFLD fibrosis score.

CONCLUSION

Excess body fat contributes to the progression of liver fibrosis regardless of metabolic health status.

Metabolically healthy obesity and risk of non-alcoholic fatty liver disease severity independent of visceral fat

BACKGROUND AND AIM

Obesity and metabolic conditions may be related to non-alcoholic fatty liver disease (NAFLD). The study assesses the risk of NAFLD according to obesity and metabolic health status in a community-based population.

METHODS

A total of 1651 subjects were recruited from the community. Individuals were categorized into four groups according to obesity status (defined as a body mass index ≥ 25 kg/m² ) and metabolically healthy status: metabolically healthy nonobesity (MHNO), metabolically healthy obesity (MHO), metabolically unhealthy nonobesity (MUHNO), and metabolically unhealthy obesity (MUHO). NAFLD was diagnosed based on a semiquantitative ultrasonography measurement. Visceral fat was assessed through bioelectrical impedance analysis and is shown by tertile (T1, T2, and T3). A proportional odds model was used to assess the cumulative risk of NAFLD.

RESULTS

The NAFLD prevalence was 26.7%, 62.8%, 47.0%, and 76.7% in subjects with MHNO, MHO, MUHNO, and MUHO, respectively (P < 0.0001). After adjustment for age, sex, exercise habits, alcohol consumption, cigarette smoking, and visceral fat, the odds ratios for more severe NAFLD were 2.44 (95% confidence interval [CI]: 1.64-3.65), 2.75 (95% CI: 1.91-3.94), and 7.41 (95% CI: 4.94-11.12) in the MHO, MUHNO, and MUHO groups, respectively, compared with the MHNO group. In addition, the odds ratios for more severe NAFLD significantly increased with the increase in visceral fat level (T2 vs T1: 3.83, 95% CI: 2.65-5.53; T3 vs T1: 9.17, 95% CI: 5.33-15.79).

CONCLUSION

Both obesity and metabolically unhealthy status were associated with a higher risk of NAFLD independent of visceral fat level.

Racial differences in prevalence and severity of non-alcoholic fatty liver disease

The aim of this review is to assess the evidence regarding racial differences in the prevalence and severity of nonalcoholic fatty liver disease (NAFLD). We reviewed the published literature that reported prevalence, severity, and genetic associations of NAFLD in different ethnic groups. The metabolic syndrome (MetS) has been associated with NAFLD, but each component of the MetS is present in various races in different percentages and their effect on NAFLD appears to be dissimilar. An elevated triglyceride (TG) level seems to have the strongest association with NAFLD. The latter is more prevalent in Hispanic patients; Blacks have lower TG levels and a lower NAFLD prevalence, compared to Caucasians or Hispanics. The severity of liver fibrosis is lower in some, but not all biopsy-based studies of Black patients. No study has evaluated the severity of liver disease controlling for the individual components of MetS, especially TG. Important racial differences in the prevalence of selected genetic polymorphisms, particularly PNPLA-3 and MBOAT7 have been documented, together with their effects on the prevalence of liver steatosis and fibrosis. Data on overall and liver mortality have found no significant differences according to race/ethnicity, with the possible exception of one paper reporting lower cirrhosis mortality in Black patients. We conclude that NAFLD is more prevalent in Hispanics and less in Blacks. This is supported by differences in key genetic polymorphisms associated with hepatic fat storage. However, there is presently insufficient evidence to firmly conclude that race, per se, plays a role in the development of liver fibrosis and its complications. Further studies, appropriately controlled for diet, exercise, and individual MetS parameters are needed.

Clinical Impact of Liraglutide as a Treatment of Obesity

Obesity is defined as a chronic, complex, relapsing disease characterized by excessive adipose tissue. Obesity impacts an individual's health by increasing complications such as prediabetes, type 2 diabetes mellitus (T2DM), hypertension, dyslipidemia, metabolic syndrome, cardiovascular disease, nonalcoholic fatty liver disease (NAFLD), cancers (eg endometrial), and obstructive sleep apnea (OSA). With the increase of obesity prevalence and its negative influences on individuals' quality of life, there is a great need for therapy with a purpose to produce sustainable weight loss of more than 10% in order to improve or even reverse the progress of obesity related complications. The GLP-1 analogue, liraglutide reduce food consumption, promote weight reduction and improve metabolic functions. The primary mechanism of GLP-1 effect on food intake, metabolism, and weight reduction is mainly due to its actions on peripheral (vagal) and central pathways and activation of hindbrain and hypothalamus. The average weight reduction induced by liraglutide was significant and the weight loss was maintained as long as the patients on therapy. Liraglutide has advantages on weight loss maintenance and promoting cardiovascular disease (CVD) risk reduction, by decreasing systolic blood pressure and glycemic index. In this review, we aim to explain the mechanism of action of Liraglutide, its pharmacokinetic properties, its clinical impact on obesity and its safety and tolerability.

Validation of Controlled Attenuation Parameter Measured by FibroScan as a Novel Surrogate Marker for the Evaluation of Metabolic Derangement

BACKGROUND/OBJECTIVES

Renaming non-alcoholic fatty liver disease (NAFLD) to metabolic dysfunction-associated fatty liver disease (MAFLD) suggests a shift of emphasis to the accompanying metabolic disturbance. Controlled attenuation parameter (CAP) measured by FibroScan has been shown to be correlated with hepatic steatosis. We aim to validate its usefulness as a novel surrogate marker for evaluating metabolic derangement.

SUBJECTS/METHODS

Volunteers were recruited from medical staff at our hospital to undergo CAP measurements. Anthropometrics, CAP, and laboratory assessments for metabolic profiles and insulin resistance were collected. CAP < 238 dB/m denoted no hepatic steatosis, 238 ≤ CAP ≤ 259 dB/m denoted mild, 260 ≤ CAP ≤ 291 dB/m denoted moderate, and CAP > 291 dB/m denoted severe hepatic steatosis according to previous reports.

RESULTS

Data of 824 participants were included for analysis. The age was 53.2 ± 15.4 years, body mass index (BMI) was 23.6 ± 3.1 kg/m², 24.4% were male subjects, and 22.0% met the criteria for metabolic syndrome (MetS). Taking the group with CAP < 238 dB/m as control, subjects with mild, moderate, and severe hepatic steatosis had increased odds of MetS by 3.51-, 3.32-, and 5.12-fold, respectively, after adjusting for multiple confounders (p = 0.020). Metabolic profiles, insulin resistance, and presence of MetS were similar between normal-weight subjects with CAP ≥ 238 dB/m and overweight subjects with CAP < 238 dB/m. Even in subjects with no MetS components, those with CAP ≥ 238 dB/m had higher BMI, waist circumferences, uric acid, triglyceride, white blood cell count, and insulin resistance, whereas lower adiponectin and estimated glomerular filtration rate. Waist circumference [OR 1.11 (1.04, 1.18), p = 0.001] and homeostatic model assessment of insulin resistance (HOMA-IR) [OR 2.39 (1.18, 4.83), p = 0.016] were predictive of hepatic steatosis according to CAP ≥ 238 dB/m.

CONCLUSIONS

CAP is a convenient, sensitive, and non-invasive indicator for metabolic derangement. Prospective studies are needed to further validate its usefulness as a surrogate marker for the transition of metabolic status over time.

Correlation of the grade of hepatic steatosis between controlled attenuation parameter and ultrasound in patients with fatty liver: a multi-center retrospective cohort study

BACKGROUND/AIMS

The controlled attenuation parameter (CAP), based on transient elastography, is widely used for noninvasive assessment of the degree of hepatic steatosis (HS). We investigated the correlation of the degree HS between CAP and ultrasound (US) in patients with HS.

METHODS

In total, 986 patients with US-based HS who underwent transient elastography within 1 month were evaluated. The US-based grade of HS was categorized as mild (grade 1), moderate (grade 2), or severe (grade 3).

RESULTS

The CAP was significantly correlated with the US-based grade of HS (r = 0.458, p < 0.001). The median CAP value of each US-based HS grade showed a positive correlation with grade (271.1, 303.7, and 326.7 dB/m for grades 1, 2, and 3). In a multivariate analysis, the US-based HS grade, body mass index, serum albumin, alanine aminotransferase, and total cholesterol, and liver stiffness were all significantly correlated with the CAP value (all p < 0.05). The areas under the receiver operating characteristic curves for grade 2 to 3 and grade 3 HS were 0.749 (95% confidence interval [CI], 0.714 to 0.784) and 0.738 (95% CI, 0.704 to 0.772). The optimal cut-off CAP values to maximize the sum of the sensitivity and specificity for grade 2 to 3 and grade 3 HS were 284.5 dB/m (sensitivity 78.6%, specificity 61.7%) and 298.5 dB/m (sensitivity 84.6%, specificity 55.6%).

CONCLUSION

The correlation of the degree of HS between CAP and US was significantly high in patients with HS, and the optimal cut-off CAP values for grade 2 to 3 and grade 3 HS were 284.5 and 298.5 dB/m.

Clinical heterogeneity in patients with non-alcoholic fatty liver disease-associated hepatocellular carcinoma

INTRODUCTION

The indisputable increase in nonalcoholic Fatty Liver Disease (NAFLD) prevalence (25% of population) has consequently led to an increase in Hepatocellular Carcinoma (HCC) and liver-related mortality worldwide. The characteristics of patients with HCC, secondary to NAFLD, are older age, large tumors due to late diagnosis, often without cirrhosis and high prevalence of the metabolic syndrome components, leading to an increased mortality rate. Although the mechanisms of disease remain partially obscure, insulin resistance, oxidative stress, apoptosis, iron overload, and excessive local and systemic inflammation are identified as culprits for hepatocarcinogenesis in the presence of NAFLD.

AREA COVERED

In this review, the authors report that there are no uniform guidelines for surveillance and early diagnosis in this patient group. Barcelona Clinic Liver Cancer staging is generally applicable to HCC due to NAFLD and management depends on liver function, tumor characteristics, and cardiovascular comorbidity. Evidence suggests that HCC due to NAFLD can be associated with worse survival due to late diagnosis.

EXPERT OPINION

The need for effective early diagnosis and management of NAFLD is urgent, considering the galloping incidence of the obesity and the fact that liver cirrhosis and HCC due to NAFLD will become the first indication for liver transplantation in foreseeable future.

Elevated Glycated Hemoglobin Is Associated With Liver Fibrosis, as Assessed by Elastography, in a Population-Based Study of Mexican Americans

Diabetes is associated with liver disease and risk of hepatocellular carcinoma. In this study, we evaluated the association between liver fibrosis measured by transient elastography and four glucose metabolism measures in the Cameron County Hispanic Cohort, a population-based, randomly selected cohort of Mexican American Hispanics with high rates of diabetes and liver cancer. We measured liver fibrosis (a risk factor for hepatocellular carcinoma) in 774 well-characterized cohort participants using transient elastography. We evaluated the association of liver fibrosis with glycated hemoglobin (HbA1c), fasting blood glucose, insulin, and insulin resistance using multivariable linear regression models. In multivariable models, log-transformed HbA1c had the strongest association with liver fibrosis (β = 0.37, 95% confidence interval [CI] 0.04-0.69, P = 0.038), after controlling for waist circumference, aspartate aminotransferase, alanine aminotransferase, liver fat, and other known confounders. The association was statistically significant among women (β = 0.33, 95% CI 0.10-0.56, P = 0.009) and similar but nonsignificant among men (β = 0.41, 95% CI -0.17 to 0.98, P = 0.593). Waist circumference, platelet count, aspartate transaminase, and liver steatosis were each associated with liver stiffness. Conclusions: Elevated HbA1c is associated with liver fibrosis, a key risk factor for HCC, particularly among women. Our results indicate that Mexican Americans with uncontrolled HbA1c may benefit from routine screening by liver elastography to identify individuals at risk of liver disease progression.

Global prevalence, incidence, and outcomes of non-obese or lean non-alcoholic fatty liver disease: a systematic review and meta-analysis

BACKGROUND

Although non-alcoholic fatty liver disease (NAFLD) is commonly associated with obesity, it is increasingly being identified in non-obese individuals. We aimed to characterise the prevalence, incidence, and long-term outcomes of non-obese or lean NAFLD at a global level.

METHODS

For this systematic review and meta-analysis, we searched PubMed, Embase, Scopus, and the Cochrane Library from inception to May 1, 2019, for relevant original research articles without any language restrictions. The literature search and data extraction were done independently by two investigators. Primary outcomes were the prevalence of non-obese or lean people within the NAFLD group and the prevalence of non-obese or lean NAFLD in the general, non-obese, and lean populations; the incidence of NAFLD among non-obese and lean populations; and long-term outcomes of non-obese people with NAFLD. We also aimed to characterise the demographic, clinical, and histological characteristics of individuals with non-obese NAFLD.

FINDINGS

We identified 93 studies (n=10 576 383) from 24 countries or areas: 84 studies (n=10 530 308) were used for the prevalence analysis, five (n=9121) were used for the incidence analysis, and eight (n=36 954) were used for the outcomes analysis. Within the NAFLD population, 19·2% (95% CI 15·9-23·0) of people were lean and 40·8% (36·6-45·1) were non-obese. The prevalence of non-obese NAFLD in the general population varied from 25% or lower in some countries (eg, Malaysia and Pakistan) to higher than 50% in others (eg, Austria, Mexico, and Sweden). In the general population (comprising individuals with and without NAFLD), 12·1% (95% CI 9·3-15·6) of people had non-obese NAFLD and 5·1% (3·7-7·0) had lean NAFLD. The incidence of NAFLD in the non-obese population (without NAFLD at baseline) was 24·6 (95% CI 13·4-39·2) per 1000 person-years. Among people with non-obese or lean NALFD, 39·0% (95% CI 24·1-56·3) had non-alcoholic steatohepatitis, 29·2% (21·9-37·9) had significant fibrosis (stage ≥2), and 3·2% (1·5-5·7) had cirrhosis. Among the non-obese or lean NAFLD population, the incidence of all-cause mortality was 12·1 (95% CI 0·5-38·8) per 1000 person-years, that for liver-related mortality was 4·1 (1·9-7·1) per 1000 person-years, cardiovascular-related mortality was 4·0 (0·1-14·9) per 1000 person-years, new-onset diabetes was 12·6 (8·0-18·3) per 1000 person-years, new-onset cardiovascular disease was 18·7 (9·2-31·2) per 1000 person-years, and new-onset hypertension was 56·1 (38·5-77·0) per 1000 person-years. Most analyses were characterised by high heterogeneity.

INTERPRETATION

Overall, around 40% of the global NAFLD population was classified as non-obese and almost a fifth was lean. Both non-obese and lean groups had substantial long-term liver and non-liver comorbidities. These findings suggest that obesity should not be the sole criterion for NAFLD screening. Moreover, clinical trials of treatments for NAFLD should include participants across all body-mass index ranges.

FUNDING

None.

HWL-088, a new and highly effective FFA1/PPARδ dual agonist, attenuates nonalcoholic steatohepatitis by regulating lipid metabolism, inflammation and fibrosis

OBJECTIVES

Nonalcoholic fatty liver (NAFLD), a chronic progressive liver disease, is highly correlated with pathoglycemia, dyslipidemia and oxidative stress. The free fatty acid receptor 1 (FFA1) agonists have been reported to improve liver steatosis and fibrosis, and the peroxisome proliferator-activated receptor δ (PPARδ) plays a synergistic role with FFA1 in energy metabolism and fibrosis. HWL-088, a PPARδ/FFA1 dual agonist, exerts better glucose-lowering effects than the representative FFA1 agonist TAK-875. However, the ability of HWL-088 to protect NAFLD was unknown. This study aimed to discover a new strategy for the treatment of NAFLD.

METHODS

The methionine- and choline-deficient diet (MCD)-induced Nonalcoholic steatohepatitis (NASH) model was constructed to evaluate the effects of HWL-088.

KEY FINDINGS

Administration of HWL-088 exerted multiple benefits on glucose control, lipid metabolism and fatty liver. Further mechanism research indicated that HWL-088 promotes lipid metabolism by decreasing lipogenesis and increasing lipolysis. Moreover, HWL-088 attenuates NASH by regulating the expression levels of genes related to inflammation, fibrosis and oxidative stress.

CONCLUSIONS

These positive results indicated that PPARδ/FFA1 dual agonist HWL-088 might be a potential candidate to improve multiple pathogenesis of NASH.

Pathogenesis of non-alcoholic fatty liver disease and implications on cardiovascular outcomes in liver transplantation

Along with the obesity epidemic there has been a major increase in non-alcoholic fatty liver disease (NAFLD) prevalence, paralleling a steady increase in cirrhosis of the liver and hepatocellular cancer (HCC) related to NAFLD. Currently, NAFLD (related HCC and cirrhosis) is the second most common cause for liver transplantation (LT) and it is projected to take the top spot in the next 3-5 years. Patients with NAFLD cirrhosis and HCC have a unique set of comorbidities which potentially increases their risk for cardiovascular disease (CVD) and mortality. However, a review of the published data in NAFLD patients who undergo LT, does not paint a clear picture. While CVD is the most common cause of non-graft related mortality over the long-term, the short and intermediate-term survival post LT in NAFLD cirrhosis appears to be on par with other etiologies when age and comorbidities are factored. The cardiovascular complications are increased in the immediate post-transplant period but there is a shift from ischemic complications to arrhythmias and heart failure (HF). NAFLD recurs in 80-100% patients and occurs de novo in about 50% after LT, potentially impacting their long-term morbidity and mortality. This review summarizes the available data on CVD in NAFLD patients before and after LT, explains what is currently known about the epidemiology and pathogenesis of CVD in NAFLD and posits strategies to improve wait-list and post-transplant survival.

Epidemiology and pathophysiology of the association between NAFLD and metabolically healthy or metabolically unhealthy obesity

The prevalence of nonalcoholic fatty liver disease (NAFLD) is continuing to rise in many countries, paralleling the epidemic of obesity worldwide. In the last years, the concept of metabolically healthy obesity [MHO, generally defined as obesity without metabolic syndrome (MetS)] has raised considerable scientific interest. MHO is a complex phenotype with risks intermediate between metabolically healthy individuals with normal-weight (NWMH) and patients who are obese and metabolically unhealthy (MUO, i.e. obesity with MetS). In this review we aimed to examine the association and pathophysiological link of NAFLD with MHO and MUO. Compared to NWMH individuals, patients with obesity, regardless of the presence of MetS features, are at higher risk of all-cause mortality and cardiovascular events. Moreover, MHO patients have a greater risk of NAFLD development and progression compared to NWMH individuals. However, this risk is generally lower than that of MUO patients, suggesting a stronger adverse effect of coexisting MetS disorders than obesity per se on the severity of NAFLD. Nevertheless, since MHO is a dynamic state (with a significant proportion of MHO subjects progressing to MUO over time) and NAFLD itself may predict the transition from MHO to MUO, we believe that any effort should be made to identify NAFLD in all obese individuals, although they appear to be "metabolically healthy". Future research is needed to better understand the role of NAFLD and other pathogenic factors potentially involved in the transition from MHO to MUO and to elucidate how this transition may affect the presence and severity of NAFLD.

Impact of obesity and metabolic health status in the development of non-alcoholic fatty liver disease (NAFLD): A United Kingdom population-based cohort study using the health improvement network (THIN)

BACKGROUND

With the obesity epidemic reaching crisis levels, there has been attention around those who may be resilient to the effects of obesity, termed metabolically healthy obesity (MHO), who initially present without associated metabolic abnormalities. Few longitudinal studies have explored the relationship between MHO and non-alcoholic fatty liver disease (NAFLD), which we address using over 4 million primary care patient records.

METHODS

A retrospective population-based longitudinal cohort was conducted using The Health Improvement Network (THIN) database incorporating adults with no history of NAFLD or alcohol excess at baseline. Individuals were classified according to BMI category and metabolic abnormalities (diabetes, hypertension and dyslipidaemia). Diagnosis of NAFLD during follow-up was the primary outcome measure. NAFLD was identified by Read codes.

RESULTS

During a median follow-up period of 4.7 years, 12,867 (0.3%) incident cases of NAFLD were recorded in the cohort of 4,121,049 individuals. Compared to individuals with normal weight and no metabolic abnormalities, equivalent individuals who were overweight, or obese were at significantly greater risk of incident NAFLD (Adjusted HR 3.32 (95%CI 2.98-3.49), and 6.92 (6.40-7.48, respectively). Metabolic risk factors further increased risk, including in those with normal weight and 1 (2.27, 1.97-2.61) or = < 2 (2.39, 1.99-2.87) metabolic abnormalities.

CONCLUSIONS

MHO individuals are at greater risk of developing NAFLD compared to those with normal weight. This finding supports that the MHO phenotype is a temporary state, and weight must be considered a risk factor even before other risk factors develop. Being normal weight with metabolic abnormalities was also associated with risk of NAFLD.

Association between Serum Uric Acid and Nonalcoholic Fatty Liver Disease in Nonobese Postmenopausal Women: A Cross-sectional Study

This study aimed to determine the association between serum uric acid (sUA) and nonalcoholic fatty liver disease (NAFLD) in nonobese postmenopausal women. A total of 4323 female individuals over 18 years of age participated in this cross-sectional study. The subjects were divided into four groups according to menopause status and body mass index. sUA quartiles in this female population were categorized as follows: Q1 ≤ 230 mmol/L, Q2: 231-270 mmol/L, Q3: 271-310 mmol/L and Q4: ≥ 311 mmol/L. The presence or absence of NAFLD was assessed by abdominal ultrasonography. The prevalence of NAFLD was 38.8% in the general population, and the average age was 46.5 ± 11.3 years. Among nonobese and obese subjects, the prevalence of NAFLD was lower in nonmenopausal subjects than in postmenopausal subjects (nonobese: 20.74% vs 45.26%, respectively, P < 0.0001; obese: 70.51% vs 84.35%, respectively, P < 0.0001). After adjusting for age, current smoking status, current alcohol drinking status, diabetes, hypertension disease and triglyceride, the ORs (95% CIs) for NAFLD among individuals in Q2-Q4 were 1.518 (1.062-2.169), 1.431 (1.010-2.027) and 2.054 (1.442-2.927), respectively, P value for trend <0.0001. Higher sUA levels can be used as a predictive biomarker for NAFLD in nonobese postmenopausal women.

Obesity is an Independent Risk Factor for Mortality in Otherwise Healthy Patients After Hepatectomy

BACKGROUND

Obesity is often associated with comorbidities that limit remnant liver recovery after hepatectomy. The extent to which obesity, in the absence of comorbidities, impacts surgical risk after hepatectomy is unknown. We hypothesized that an obese population without major comorbidities would not be at increased risk of adverse outcomes after hepatectomies.

METHODS

We performed a retrospective analysis identifying patients who underwent hepatectomies from the American College of Surgeons National Surgical Quality Improvement Program data set 2005-2017. Outcomes of interest included the following: mortality, any morbidity, critical care complications, and failure to discharge home. Body mass index (BMI) was the primary variable of interest, grouped as ≥35 and <35 based on bivariate tests of associations with candidate cut-off points. In attempt to isolate the effect of obesity on outcomes among patients "without major comorbidities" (WOC), we included patients without diabetes, chronic obstructive pulmonary disease, renal insufficiency, and nonsmokers; remaining patients were grouped as "with major comorbidities" (WC). Multivariable logistic regression was used to test whether obesity is independently associated with the outcomes of interest after adjustment for other covariates.

RESULTS

A total of 36,396 patients were included. There were 13,754 patients in the WOC group and 22,642 in the WC group. Among patients in the WOC group, the adjusted odds of mortality were 2.2 times higher for patients with a BMI ≥35 versus a BMI <35. Among the patients in the WC group, a BMI ≥35 was not a statistically significant predictor of mortality after adjustment for other covariates. Obese patients had increased odds of each outcome among the WOC group.

CONCLUSIONS

Our hypothesis was refuted by these data. In fact, the adverse effect of obesity was more evident among healthy patients.

Orlistat-Induced Gut Microbiota Modification in Obese Mice

Introduction

Accumulating evidence has indicated that alterations of gut microbiota have been involved in various metabolic diseases. Orlistat, a reversible inhibitor of pancreatic and gastric lipase, has beneficial effects on weight loss and metabolism. However, the effect of orlistat on the composition of gut microbiota remains unclear.

Objective

We aimed to explore the effect of orlistat on gut microbiota in high-fat diet (HFD) fed C57BL/6J obese mice.

Methods

C57BL/6J mice were randomly divided into three groups: control (NCD), HFD, and HFD + orlistat (ORL). Mice in the NCD group were fed chow diet, while the other groups were fed HFD for 6 months, and orlistat was added in the final 3 months in the HFD + ORL group. After sacrifice, body weight and metabolic parameters were assessed, and the gut microbial composition was analyzed by 16S rRNA gene sequencing.

Results

Orlistat treatment exerted beneficial effects on body weight, plasma cholesterol, and glucose tolerance. Meanwhile, orlistat treatment modified the gut microbiota, presenting as reduced total microbial abundance and obvious upregulated bacteria. Moreover, the upregulated bacteria correlated with several metabolic pathways.

Conclusions

Orlistat may exert beneficial effects on body weight and glucose tolerance through modifying the composition of gut microbiota.

Dietary Silk Peptide Prevents High-Fat Diet-Induced Obesity and Promotes Adipose Browning by Activating AMP-Activated Protein Kinase in Mice

Obesity is associated with metabolic syndrome and other chronic diseases, and is caused when the energy intake is greater than the energy expenditure. We aimed to determine the mechanism whereby acid-hydrolyzed silk peptide (SP) prevents high-fat diet-induced obesity, and whether it induces browning and fatty acid oxidation (FAO) in white adipose tissue (WAT), using in vivo and ex vivo approaches. We determined the effects of dietary SP in high-fat diet-fed obese mice. The expression of adipose tissue-specific genes was quantified by western blotting, qRT-PCR, and immunofluorescence analysis. We also investigated whether SP directly induces browning in primarily subcutaneous WAT-derived adipocytes. Our findings demonstrate that SP has a browning effect in WAT by upregulating AMP-activated Protein Kinase (AMPK) phosphorylation and uncoupling protein 1 (UCP1) expression. SP also suppresses adipogenesis and promotes FAO, implying that it may have potential as an anti-obesity drug.

Childhood Obesity Risk in Relationship to Perilipin 1 (PLIN1) Gene Regulation by Circulating microRNAs

Childhood obesity is a growing public health burden in many countries. The lipid perilipin 1 (PLIN1) gene is involved in regulation of lipolysis, and thus represents a viable candidate mechanism for obesity genetics research in children. In addition, the regulation of candidate gene expression by circulating microRNAs (miRNAs) offers a new research venue for diagnostic innovation. We report new findings on associations among circulating miRNAs, regulation of the PLIN1 gene, and susceptibility to childhood obesity. In a sample of 135 unrelated subjects, 35 children with obesity (between ages 3 and 13) and 100 healthy controls (between ages 4 and 16), we examined the expression levels of four candidate miRNAs (hsa-miR-4777-3p, hsa-miR-642b-3p, hsa-miR-3671-1, and hsa-miR-551b-2) targeting the PLIN1 as measured by real-time polymerase chain reaction in whole blood samples. We found that the full genetic model, including the four candidate miRNAs and the PLIN1 gene, explained a statistically significant 12.7% of the variance in childhood obesity risk (p = 0.0034). The four miRNAs together explained 10.1% of the risk (p = 0.008). The percentage of variation in childhood obesity risk explained by hsa-miR-642b-3p and age was 19%. In accordance with biological polarity of the observed association, for example, hsa-miR-642b-3p was upregulated, while the PLIN1 expression decreased in obese participants compared to healthy controls. To the best of our knowledge, this is the first clinical association study of these candidate miRNAs targeting the PLIN1 in childhood obesity. These data offer new molecular leads for future clinical biomarker and diagnostic discovery for childhood obesity.

Clinic, Anthropometric And Metabolic Changes In Adults With Class III Obesity Classified As Metabolically Healthy And Metabolically Unhealthy

PURPOSE

To describe clinical, biochemical and anthropometric profiles in adults with class III obesity classified as metabolically healthy obesity (MHO) and metabolically unhealthy obesity (MUHO).

PATIENTS AND METHODS

This is a cross-sectional study with patients classified as MHO and MUHO according to the NCEP-ATP III. Anthropometric, biochemical and clinical variables were analyzed.

RESULTS

A total of 223 subjects were evaluated and 32.73% were classified as MHO and 67.26% as MUHO, respectively. The insulin resistance homeostasis model (HOMA-IR) showed elevation in the MUHO group (p=0.003) and anthropometric variables were correlated with bone markers [body index mass (BMI) vs phosphorus: r=0.31, p<0.001; BMI vs 25(OH)D: r=-0.31, p=0.041]. Visceral adiposity index was lower in MHO (p=0.001). Negative correlations between inflammatory markers and bone markers were observed in the MHO group (calcium vs C-reactive protein: -0.30, p=0.017; parathyroid hormone vs HOMA-IR: r=-0.28, p=0.017.

CONCLUSION

MHO individuals showed important metabolic changes, such as those observed in MUHO, despite lower prevalence and severity. Continuous monitoring of these individuals is suggested, given the transient nature of the MHO phenotype.

Examining the associations among intraocular pressure, hepatic steatosis, and anthropometric parameters

Emerging evidences had reported the positive relationship between obesity and intraocular pressure (IOP). The aim of the present study was to investigate the association between hepatic steatosis and IOP in an adult Taiwanese population.Seven thousand seven hundred twelve males and 6325 females who received a health examination at the Tri-Service General Hospital during the period from 2010 to 2016 were included in this study.IOP was measured by noncontact tonometry. Hepatic steatosis was diagnosed by abdominal ultrasound examination. Multivariate regression analyses were used to assess the associations among various anthropometric parameters and IOP.After adjusting for pertinent covariables, hepatic steatosis had a closer association with increased IOP than percentage body fat, body mass index, or waist circumference (β = 0.017, 95% confidence interval [CI] = 0.006, 0.028). This relationship remained significant among males in the study population (β = 0.015, 95% CI = 0.001, 0.029). Furthermore, hepatic steatosis was significantly correlated with increased risk of high IOP (odd ratios = 1.235, 95% CI = 1.041-1.465).Our study highlights that hepatic steatosis is a better index for assessing the relationship with increased IOP than other anthropometric parameters. Underlying pathophysiological mechanisms regulating the association between hepatic steatosis and increasing IOP and even the risk of glaucoma should be examined in further studies.

Metabolically healthy versus unhealthy obesity and risk of fibrosis progression in non-alcoholic fatty liver disease

BACKGROUND & AIMS

Little is known about the impact of metabolically healthy obesity on fibrosis progression in non-alcoholic fatty liver disease (NAFLD). We investigated the association of body mass index (BMI) category, body fat percentage and waist circumference with worsening of noninvasive fibrosis markers in metabolically healthy and unhealthy individuals with NAFLD.

METHODS

A cohort study was performed on 59 957 Korean adults with NAFLD (13 285 metabolically healthy and 46 672 metabolically unhealthy individuals) who were followed for a median of 7.7 years. Being metabolically healthy was defined as not having any metabolic syndrome component and having a homoeostasis model assessment of insulin resistance <2.5. Progression from low to intermediate or high probability of advanced fibrosis was assessed using the NAFLD fibrosis score (NFS).

RESULTS

During 339 253.1 person-years of follow-up, 9857 subjects with low NFS at baseline progressed to intermediate or high NFS. Among metabolically healthy individuals, the multivariable-adjusted HRs (95% CI) for NFS worsening comparing BMIs 23-24.9, 25-29.9 and ≥30 with a BMI of 18.5-22.9 kg/m² were 1.19 (1.00-1.42), 1.79 (1.52-2.10) and 3.52 (2.64-4.69), respectively, whereas the corresponding HRs (95% CI) in metabolically unhealthy individuals were 1.37 (1.24-1.52), 2.18 (1.99-2.39) and 4.26 (3.83-4.75). A similar trend was observed in the analyses using body fat and waist circumference.

CONCLUSION

In the large-scale cohort of young and middle-aged individuals with NAFLD, BMI was positively associated with worsening of noninvasive fibrosis marker regardless of metabolic health status. Excess adiposity per se, even without accompanying metabolic health status, may contribute to fibrosis progression in NAFLD.

Does the Metabolically Healthy Obese Phenotype Protect Adults with Class III Obesity from Biochemical Alterations Related to Bone Metabolism?

Obesity negatively affects the relationship between markers and micronutrients of bone metabolism. Testing the hypothesis that the metabolically healthy obese phenotype might be protected by those alterations was the aim of this study. A cross-sectional study was carried out in adults with class III obesity classified in Metabolically Healthy Obese (MHO) and Metabolically Unhealthy Obese (MUHO), according to the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (NCEP ATP III) criteria. Anthropometric, biochemical, and clinical variables were analyzed for sample characterization. To evaluate bone metabolism, markers (alkaline phosphatase and parathyroid hormone—PTH) and related nutrients (vitamin D, vitamin B12, calcium, phosphorus, magnesium, potassium and zinc) were analyzed. A total of 223 adults with class III obesity aged 41.20 ± 10.15 years were included. The MHO phenotype was identified in 32.73% of the sample. After logistic regression, it was observed that inadequacies of calcium (OR: 4.11; 95% CI: 2.33–6.66), phosphorus (OR: 3.03; 95% CI: 1.98–5.79), vitamin D (OR: 5.01; 95% CI: 2.92–6.71) and PTH (OR: 5.45; 95% CI: 4.49–6.74) were significantly higher in the MUHO group compared to the MHO Group. This study showed that the MHO phenotype does not protect adults from alterations in markers and micronutrients of bone metabolism. However, the MUHO phenotype presents a higher risk for alterations related to bone metabolism, which can favor the emergence of metabolic bone diseases.

Predictive effects of body mass index on immune reconstitution among HIV-infected HAART users in China

BACKGROUND

Body mass index (BMI) may contribute somewhat to drug metabolism, and thus affecting the efficacy of highly active antiretroviral therapy (HAART). This study aimed to determine the frequencies of underweight, normal and overweight/obesity at pre-HAART in a large cohort of HIV-infected Chinese patients, and investigate the prospective effects of BMI on immune reconstitution after HAART initiation.

METHODS

A longitudinal cohort study was performed to analyze the effects of BMI on immune reconstitution in HIV-infected patients treated with HAART. Multiple linear regression was used to evaluate the relationship between baseline BMI and increased CD4+ T lymphocyte levels at 12 and 30 months after initiating HAART. In addition, Cox proportional hazard model was used to assess the relationship between BMI and time to achieve immunologic reconstitution (CD4+ T lymphocytes>500cells/μL) during the follow-up period.

RESULTS

Among the 1612 enrolled patients, 283 (17.6%) were overweight/obese (BMI ≥ 25 kg/m²), 173 (10.7%) were underweight (BMI < 18.5 kg/m²) and the remaining were normal weight. Prior to HAART initiating, overweight HIV-infected patients were mostly males, older ages, exhibited higher CD4+ T lymphocytes and lower viral loads (p < 0.01 for all). Patients with higher baseline BMI had an independently positive effect on 30-month CD4+ T lymphocyte recovery (p = 0.028), but not 12-month CD4+ T lymphocyte gain (p = 0.104). In addition, a Cox proportional hazard model with baseline BMI as an independent variable indicated that BMI was correlated with an increased likelihood of achieving immunologic reconstitution over time (hazard ratios [HR] 1.03; 95% confidence intervals [CI] 1.01-1.06; p = 0.011), after adjusting for baseline age, gender, CD4+ T lymphocytes, CD4/CD8 ratio, viral load and WHO stage.

CONCLUSIONS

Higher baseline BMI could predict better immune reconstitution in HIV-infected patients after HAART initiating.

Betulinic acid alleviates endoplasmic reticulum stress-mediated nonalcoholic fatty liver disease through activation of farnesoid X receptors in mice

BACKGROUND AND PURPOSE

The molecular mechanism for the pathogenesis of nonalcoholic fatty liver disease (NAFLD) remains elusive. Both farnesoid X receptor (FXR) signalling and endoplasmic reticulum (ER) stress contribute to the progression of NAFLD; however, it is not clear whether the actions of these two pathways are dependent on each other. Moreover, the pharmacological benefits and mechanism of betulinic acid (BA) in controlling metabolic syndrome and NAFLD are largely unknown.

EXPERIMENTAL APPROACH

A reporter assay and a time-resolved FRET assay were used to identify BA as an agonist of the FXR. NAFLD was induced by a methionine and choline-deficient L-amino acid diet (MCD) and high-fat diet (HFD). The pharmacological effects of BA (100 mg·kg^-1 ·day^-1 ) and potential interactions between hepatic FXR activation and ER stress pathways were evaluated by FXR silencing, Western blot and RT-PCR analyses using control and FXR^-/- mice.

KEY RESULTS

Activation of the FXR inhibited intracellular PERK/EIF2α/ATF4 and CHOP signalling, thereby alleviating hepatic ER stress, whereas FXR silencing resulted in an opposite effect. Furthermore, we identified BA as an FXR agonist that effectively attenuated the progression of NAFLD and metabolic disorders in both HFD- and MCD diet-fed mice and restored the hepatocellular ER homeostasis by stimulating the FXR signalling pathway and blocking PERK/EIF2α signalling. In contrast, the effects of BA were attenuated in FXR^-/- mice.

CONCLUSIONS AND IMPLICATIONS

Our data demonstrate that pharmacological activation of the FXR by BA reduces hepatocellular ER stress and attenuates NAFLD in an animal model of hepatic steatosis.

Metabolically healthy versus metabolically unhealthy obesity

Obesity-related disease complications reduce life quality and expectancy and increase health-care costs. Some studies have suggested that obesity not always entails metabolic abnormalities and increased risk of cardiometabolic complications. Because of the lack of universally accepted criteria to identify metabolically healthy obesity (MHO), its prevalence varies widely among studies. Moreover, the prognostic value of MHO is hotly debated, mainly because it likely shifts gradually towards metabolically unhealthy obesity (MUO). In this review, we outline the differential factors contributing to the metabolic heterogeneity of obesity by discussing the behavioral, genetic, phenotypical, and biological aspects associated with each of the two metabolic phenotypes (MHO and MUO) of obesity and their clinical implications. Particular emphasis will be laid on the role of adipose tissue biology and function, including genetic determinants of body fat distribution, depot-specific fat metabolism, adipose tissue plasticity and, particularly, adipogenesis. Finally, the emerging role of gut microbiota in obesity and adipose tissue dysfunction as well as the search for novel biomarkers for the obesity-related metabolic traits and associated diseases will be briefly presented. A better understanding of the main determinants of a healthy metabolic status in obesity would allow promotion of this favorable condition by targeting the relevant pathways.

Pharmacotherapy of obesity: Available medications and drugs under investigation

Obesity is a chronic disease with a continuously rising prevalence that currently affects more than half a billion people worldwide. Energy balance and appetite are highly regulated via central and peripheral mechanisms, and weight loss triggers a homeostatic response leading to weight regain. Lifestyle and behavioral modifications are the cornerstones of obesity management; however, they often fail to achieve or sustain long-term weight loss. Pharmacotherapy added onto lifestyle modifications results in an additional, albeit limited, weight reduction. Regardless, this weight reduction of 5-10% conveys multiple cardiovascular and metabolic benefits. In this review, evidence on the food and drug administration (FDA)-approved medications, i.e., orlistat, lorcaserin, phentermine/topiramate, liraglutide and naltrexone/bupropion, is summarized. Furthermore, anti-obesity agents in the pipeline for potential future therapeutic use are presented.

Ultrasound/Elastography techniques, lipidomic and blood markers compared to Magnetic Resonance Imaging in non-alcoholic fatty liver disease adults

INTRODUCTION

Non-alcoholic fatty liver disease (NAFLD) may progress to steatohepatitis, cirrhosis and complicated hepatocellular carcinoma with defined differential symptoms and manifestations.

OBJECTIVE

To evaluate the fatty liver status by several validated approaches and to compare imaging techniques, lipidomic and routine blood markers with magnetic resonance imaging in adults subjects with non-alcoholic fatty liver disease.

MATERIALS AND METHODS

A total of 127 overweight/obese with NAFLD, were parallelly assessed by Magnetic Resonance Imaging (MRI), ultrasonography, transient elastography and a validated metabolomic designed test to diagnose NAFLD in this cross-sectional study. Body composition (DXA), hepatic related biochemical measurements as well as the Fatty Liver Index (FLI) were evaluated. This study was registered as FLiO: Fatty Liver in Obesity study; NCT03183193.

RESULTS

The subjects with more severe liver disease were found to have worse metabolic parameters. Positive associations between MRI with inflammatory and insulin biomarkers were found. A linear regression model including ALT, RBP4 and HOMA-IR was able to explain 40.9% of the variability in fat content by MRI. In ROC analyses a combination panel formed of ALT, HOMA-IR and RBP4 followed by ultrasonography, ALT and metabolomic test showed the major predictive ability (77.3%, 74.6%, 74.3% and 71.1%, respectively) for liver fat content.

CONCLUSIONS

A panel combination including routine blood markers linked to insulin resistance showed highest associations with MRI considered as a gold standard for determining liver fat content. This combination of tests can facilitate the diagnosis of early stages of non-alcoholic liver disease thereby avoiding other invasive and expensive methods.

The effects of metabolic status on non-alcoholic fatty liver disease-related outcomes, beyond the presence of obesity

BACKGROUND

Metabolically healthy obesity (MHO) shows a reduced risk compared with obese patients with adverse metabolic conditions. Lean people suffering some metabolic derangements also have non-alcoholic fatty liver disease (NAFLD)-related outcomes compared with non-obese subjects with a few metabolic risks.

AIM

To define the impact of the metabolic status on the NAFLD-related outcomes, beyond the presence of obesity.

METHODS

We designed a multicentre cross-sectional study, including 1058 biopsy-proven NAFLD patients. Metabolically healthy status was strictly defined by the lack of metabolic risk factors (diabetes mellitus, low HDL, hypertriglyceridemia, arterial hypertension). Non-alcoholic steatohepatitis (NASH) and significant fibrosis (F2-F4) were identified by liver biopsy. Chronic kidney disease epidemiology collaboration equation was calculated for kidney function and the atherogenic index of plasma (AIP) for cardiovascular risk.

RESULTS

Metabolically healthy (OR 1.88; P = 0.050) and unhealthy obesity (OR 3.47: P < 0.0001), and unhealthy non-obesity (OR 3.70; P < 0.0001) were independently associated with NASH together with homeostatic model assessment (HOMA), ALT, and platelets. Significant fibrosis was more frequently observed in the presence of adverse metabolic conditions in obese (OR 3.89; P = 0.003) and non-obese patients (OR 3.92; P = 0.002), and independently associated with platelets, albumin, ALT, HOMA, and age. The number of metabolic factors determined the risk of NASH and significant fibrosis. Glomerular filtration rate was lower in unhealthy (91.7 ± 18) than healthy metabolism (95.6 ± 17) (P = 0.007). AIP was higher in adverse metabolic conditions (P = 0.0001). Metabolically unhealthy non-obesity showed higher liver damage (NASH 55.8% vs 42.4%; P < 0.05; significant fibrosis 31.7% vs 11.4%; P < 0.0001) and cardiovascular risk (P < 0.0001) than healthy obesity.

CONCLUSIONS

Metabolic unhealthy status showed a greater impact on NASH, significant fibrosis, kidney dysfunction, and atherogenic profile than obesity. However, metabolically healthy obesity was not a full healthy condition. We should focus our messages especially on patients with adverse metabolic conditions.

Serum levels of advanced glycation end-products (AGEs) and the decoy soluble receptor for AGEs (sRAGE) can identify non-alcoholic fatty liver disease in age-, sex- and BMI-matched normo-glycemic adults

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a serious health problem affecting ~25% of the global population. While NAFLD pathogenesis is still unclear, multiple NAFLD parameters, including reduced insulin sensitivity, impaired glucose metabolism and increased oxidative stress are hypothesised to foster the formation of advanced glycation end-products (AGEs). Given the link of AGEs with end organ damage, there is scope to examine the role of the AGE/RAGE axis activation in liver injury and NAFLD.

METHODS

Age, sex and body mass index matched normo-glycemic NAFLD adults (n = 58) and healthy controls (n = 58) were enrolled in the study. AGEs were analysed by liquid chromatography-mass spectrometry (CML, CEL), fluorescence (pentosidine, AGE fluorescence), colorimetry (fructosamine) and ELISA (sRAGE). Their association with liver function, inflammation, fibrosis and stage of NAFLD was examined.

RESULTS

Early and advanced glycation end-products, except N^ε-carboxymethyl-L-lysine (CML), were 10-30% higher, sRAGE levels 1.7-fold lower, and glycation/sRAGE ratios 4-fold higher in the NAFLD cases compared to controls. While AGEs presented weak to moderate correlations with indices of liver function and damage (AST/ALT, HOMA-IR, TNF-α and TGF-β1), including sRAGE to characterize the AGEs/sRAGE axis strengthened the associations observed. High glycation/sRAGE ratios were associated with 1.3 to 14-fold likelihood of lower AST/ALT ratios. The sum of AGEs/sRAGE ratios accurately distinguished between healthy controls and NAFLD patients (area under the curve of 0.85). Elevated AGEs/sRAGE (>7.8 mmol/pmol) was associated with a 12-fold likelihood of the presence of NAFLD.

CONCLUSION

These findings strengthen the involvement of AGEs-RAGE axis in liver injury and the pathogenesis of NAFLD.

Hypothalamic endoplasmic reticulum stress as a key mediator of obesity-induced leptin resistance

Obesity is an epidemic disease that is increasing worldwide and is a major risk factor for many metabolic diseases. However, effective agents for the prevention or treatment of obesity remain limited. Therefore, it is urgent to clarify the pathophysiological mechanisms underlying the development and progression of obesity and exploit potential agents to cure and prevent this disease. According to a recent study series, obesity is associated with the development of endoplasmic reticulum stress and the activation of its stress responses (unfolded protein response) in metabolically active tissues, which contribute to the development of obesity-related insulin and leptin resistance, inflammation and energy imbalance. Hypothalamic endoplasmic reticulum stress is the central mechanism underlying the development of obesity-associated leptin resistance and disruption of energy homeostasis; thus, targeting endoplasmic reticulum stress offers a promising therapeutic strategy for improving leptin sensitivity, increasing energy expenditure and ultimately combating obesity. In this review, we highlight the relationship between and mechanism underlying hypothalamic endoplasmic reticulum stress and obesity-associated leptin resistance and energy imbalance and provide new insight regarding strategies for the treatment of obesity.

Clinical and Body Compositional Factors Associated with Metabolic Syndrome in Obese Koreans: A Cross-Sectional Study

BACKGROUND

Obesity and metabolic syndrome (MetS) are increasing rapidly worldwide, but metabolically healthy population exists. Thus, this study evaluated the proportion of obesity and MetS and investigated clinical and body compositional factors associated with MetS in obese Koreans.

METHODS

This cross-sectional observational study enrolled subjects from the Korea National Health and Nutrition Examination Survey (n = 15,408). Obesity was defined by body mass index (BMI) cutoff points of 25 and 27.5 kg/m². Clinical and laboratory parameters were compared by MetS presence and factors associated with insulin resistance or MetS in obese subjects were evaluated by multivariate or logistic regression analyses.

RESULTS

The proportion of obesity was 29.7% at a BMI cutoff point of 25 kg/m² and 10.4% at 27.5 kg/m². The proportion of MetS was greater in obese population and increased with higher obesity cutoff point, where men were more prevalent than women. The subjects with MetS showed higher age, glycated hemoglobin, insulin resistance, liver enzymes, and ferritin compared with metabolically healthy population in both obese genders. Factors associated with insulin level or presence of MetS were high trunk fat percentage, trunk-to-limb fat ratio, and trunk-to-leg fat ratio, but low limb fat percentage and leg fat percentage. Among body composition indices, trunk-to-limb fat ratio and trunk-to-leg fat ratio showed significantly high odds ratios for MetS in both obese genders regardless of BMI cutoff points.

CONCLUSIONS

MetS in obese population concurrently increased with higher obesity cutoff point. Higher age, insulin resistance, liver enzymes, ferritin, and higher proportion of truncal fat mass-to-limb or leg fat mass significantly contribute to MetS, where trunk-to-limb fat ratio and trunk-to-leg fat ratio could be helpful in identifying and preventing MetS in the obese Korean population.

The relationship between obesity and the severity of non-alcoholic fatty liver disease: systematic review and meta-analysis

A number of researches have explored the association between obesity and nonalcoholic fatty liver disease (NAFLD) liver function, histopathology, complications, genetic factors and prognosis, but the results were conflicting and inconclusive. Areas covered: In this meta-analysis, the liver function, histopathology, metabolic complications, patatin-like phospholipase domain-containing protein 3 (PNPLA3) genetic polymorphism and prognosis were compared between non-obese and obese NAFLD. Pubmed, EMBASE, Cochrane databases were searched to identify eligible studies. The odds ratio (OR) or standardized mean difference (SMD) with 95% confidence intervals (CI) were pooled using fixed- or random-effects models. Expert commentary: This meta-analysis indicated that for NAFLD patients, obesity (according to ethnic-specific BMI cut-off points to define obesity) could predict a worse long-term prognosis. However, obesity may not be an independent factor for the development of NASH or advanced fibrosis in NAFLD patients and NAFLD should be considered as potential population for pharmacologic treatment regardless of obesity. In addition, PNPLA3 rs738409 may be more relevant to the progression of non-obese NAFLD when compared to obese NAFLD. Importantly, large-sample, long-term follow-up cohort studies based on liver biopsy are highly needed due to limited liver pathology and long-term follow-up data at present.

Association of Adipokines with Development and Progression of Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is a chronic liver disease affecting 30% of the general population and 40% to 70% of obese individuals. Adipose tissue plays a crucial role in its pathogenesis, as it produces and secretes pro- and anti-inflammatory cytokines called adipokines. Adiponectin and leptin have well-determined actions in terms of NAFLD pathophysiology. Adiponectin deficiency is associated with a pro-inflammatory condition, as it is observed in obesity and other metabolic disorders. On the other hand, increased leptin levels, above the normal levels, act as a pro-inflammatory stimulus. Regarding other adipokines (resistin, visfatin, chemerin, retinol-binding protein 4, irisin), data about their contribution to NAFLD pathogenesis and progression are inconclusive. In addition, pharmacological agents like thiazolidinediones (pioglitazone and rosiglitazone), that are used in the management of NAFLD exert favourable effects on adipokine levels, which in turn may contribute to the improvement of liver function. This review summarizes the current knowledge and developments in the association between adipokines and NAFLD and discusses possible therapeutic implications targeting the modulation of adipokine levels as a potential tool for the treatment of NAFLD.