Hyperinsulinemia predisposes to NAFLD

Hyoscyamus albus nortropane alkaloids reduce hyperglycemia and hyperinsulinemia induced in HepG2 cells through the regulation of SIRT1/NF-kB/JNK pathway

BACKGROUND

Chronic superphysiological glucose and insulin concentrations are known to trigger several tissue and organ failures, including insulin resistance, oxidative stress and chronic low-grade inflammation. Hence, the screening for molecules that may counteract such conditions is essential in current existing therapeutic strategies, thereby the use of medicinal plant derivatives represents a promising axis in this regard.

METHODS

In this study, the effect of a selected traditional medicinal plant, Hyoscyamus albus from which, calystegines have been isolated, was investigated in an experimental model of hyperinsulinemia and hyperglycemia induced on HepG2 cells. The mRNA and protein expression levels of different insulin signaling, gluconeogenic and inflammatory pathway- related molecules were examined. Additionally, cell viability and apoptosis, oxidative stress extent and mitochondrial dysfunctions were assayed using flow cytometric and qRT-PCR techniques.

RESULTS

Treatment of IR HepG2 cells with calystegines strongly protected the injured cells from apoptosis, oxidative stress and mitochondrial integrity loss. Interestingly, nortropane alkaloids efficiently regulated the impaired glucose metabolism in IR HepG2 cells, through the stimulation of glucose uptake and the modulation of SIRT1/Foxo1/G6PC/mTOR pathway, which is governing the hepatic gluconeogenesis. Furthermore, the alkaloidal extract restored the defective insulin signaling pathway, mainly by promoting the expression of Insr at the mRNA and protein levels. What is more, treated cells exhibited significant mitigated inflammatory response, as evidenced by the modulation and the regulation of the NF- κB/JNK/TLR4 axis and the downstream proinflammatory cytokines recruitment.

CONCLUSION

Overall, the present investigation demonstrates that calystegines from Hyoscyamus albus provide cytoprotection to the HepG2 cells against insulin/glucose induced insulin resistance and apoptosis due to the regulation of SIRT1/Foxo1/G6PC/mTOR and NF-κB/JNK/TLR4 signaling pathways. Video Abstract.

Association of dietary insulinaemic potential and odds of non-alcoholic fatty liver disease among adults: A case-control study

BACKGROUND

Hyperinsulinaemia is considered as a major risk factor for the development of a myriad of chronic diseases. We examined the association between the dietary insulinaemic potential and the odds of non-alcoholic fatty liver disease (NAFLD) among Iranian adults.

METHODS

After being subjected to a liver ultrasound, 166 patients with NAFLD and 200 controls were included in the study. The dietary intakes and the physical activity levels of the participants were evaluated using a validated semi-quantitative food frequency questionnaire and the International Physical Activity Questionnaire (short IPAQ), respectively. The insulinaemic potential of the diet was assessed by computing the scores of the Empirical Dietary Index for Hyperinsulinemia (EDIH) and the Empirical Dietary Index for Insulin Resistance (EDIR).

RESULTS

Compared with the control subjects, patients with NAFLD were significantly older; had higher values for body mass index, fasting blood sugar, triglycerides, low-density lipoprotein cholesterol, total cholesterol and alanine transaminase; and were more likely to smoke. Moreover, NAFLD patients had significant lower levels of high-density lipoprotein cholesterol and were less likely to perform physical activity. The risk of NAFLD was higher in the individuals in the highest tertile of the EDIH (odds ratio [OR] = 2.79; 95% confidence interval [CI] = 1.32-5.90; p value for trend < 0.05) and EDIR (OR = 2.42; 95% CI = 1.22-4.79; p value for trend < 0.05) compared to those in the lowest tertile of these scores.

CONCLUSIONS

Our study indicates that a higher dietary insulinaemic potential is associated with an increased risk of NAFLD.

The association between food insulin index and odds of non-alcoholic fatty liver disease (NAFLD) in adults: a case-control study

AIM

This research aimed to study the association of food insulin index and biochemical parameters with the odds of developing NAFLD in adult Iranians.

BACKGROUND

Hyperinsulinemia may play an important role in the development of non-alcoholic fatty liver disease (NAFLD) because of the relationship between insulin response and body fat accumulation.

METHODS

A case-control study of 169 NAFLD patients and 200 healthy adults aged 18-55 years was conducted. Dietary data was collected using a validated 168-item quantitative food frequency questionnaire (FFQ). Food insulin index (FII) was calculated by dividing the total insulin load by total energy intake (kcal/day). Total insulin load (ILoverall) was also calculated using a standard formula.

RESULTS

Mean participant age was 43.9 ± 5.9 years. Patients with NAFLD were significantly associated with higher body mass index, levels of liver enzymes, triglyceride, low density lipoprotein-cholesterol (LDL), total cholesterol, and fasting blood sugar (FBS) compared to the healthy subjects (p < 0.05). The highest tertiles of FII were associated with higher odds of NAFLD (OR=1.4, 95% CI: 0.88-2.48, p for trend <0.001) and obesity (OR=2.33, 95% CI: 0.97-5.75) compared to the lowest tertiles. Potential confounders for the association were controlled.

CONCLUSION

This study found that adherence to a diet with high FII was associated with greater odds of NAFLD and overweight or obesity. Additional studies are required to better understand this association.

Antidiabetic Drugs and Statins in Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) has become the most prevalent liver disease worldwide. Despite its high prevalence and rising incidence, there are currently no specific targeted pharmacotherapies approved by the Food and Drug Administration (FDA) for nonalcoholic steatohepatitis (NASH). Current therapies for patients with NAFLD include lifestyle modification. Vitamin E and pioglitazone are recommended for those confirmed to have NASH. However, there are concerns about the long-term safety of both pioglitazone and vitamin E in higher doses. Metformin is essential for managing the abnormal metabolic parameters in patients with NAFLD. Glucagon-like peptide-1 analogue, sodium-dependent glucose cotransporter inhibitors, and peroxisome proliferator-activated receptor agonists have shown benefits in improving metabolic parameters and reducing hepatic lipid accumulation and inflammation. However, the role of these antidiabetic agents in specifically reversing NASH needs to be established. Indeed, statins have been underprescribed in patients with NASH owing to fear of hepatotoxicity despite coronary artery disease being a common cause of death in patients with NAFLD. Statins reduce the risk of cardiovascular morbidity and mortality in patients with NASH and dyslipidemia. However, their use specifically for treatment of NASH needs further evaluation. Optimizing the control of risk factors remains the main strategy for treatment until targeted pharmacotherapies for NASH are available.

The value of neck circumference (NC) as a predictor of non-alcoholic fatty liver disease (NAFLD)

Aims

To analyze the correlation between neck circumference (NC) and non-alcoholic fatty liver disease (NAFLD) and compare the predictive value of NC for NAFLD with that of other simple anthropometric measures and other biochemical profiles.

Methods

2761 subjects, undergoing a medical check-up at the Changhai Hospital between October 01, 2012 and November 30, 2012, were recruited to the study. NC, other simple anthropometric measures, and biochemical profiles were analyzed.

Results

NC in NAFLD subjects with or without elevated ALT were 38.94 ± 2.62 cm and 37.21 ± 3.06 cm respectively, which was significantly higher than that in subjects with other metabolic disorders (NC: 35.33 ± 3.03 cm) and in normal controls (NC: 32.60 ± 2.37) (both P < 0.001). NC in women with NAFLD increased by 1 cm and fasting insulin (FINS) and homeostasis model assessment-insulin resistance (HOMA-IR) increased by 1.87 mIU/L and 1.43, respectively. Compared with other anthropometric measures, neck circumference-height ratio (NHtR) had a significant impact both on the incidence of NAFLD. After adjustment for sex, abdominal obesity and other influencing factors, the incidence of NAFLD still tended to positively correlate with NC. Optimal cut-off points of NC and NHtR for predicting NAFLD in males were 37.25 cm and 0.224, respectively, and such points in females were 32.90 cm and 0.208, respectively.

Conclusion

NC was wider in NAFLD patients than in healthy subjects and other metabolic disorder sufferers. NC and NHtR could be used as simple predictive tools for NAFLD.

Study of metabolic syndrome and its risk components in patients attending tertiary care center of uttarakhand

Metabolic syndrome is a complex of metabolic factors which includes central obesity, insulin-resistance, dyslipidemia and hypertension. Metabolic syndrome is associated with increased risk of cardiovascular disease. This study aimed to know the rate of metabolic syndrome in outpatients presenting to medicine department of our hospital and their profile. The metabolic syndrome was diagnosed using International Diabetes Federation criteria. The parameters analyzed included age, sex, blood pressure, BMI, fasting plasma glucose, HDL and triglycerides. The rate of metabolic syndrome was 21.1 % in our study. The younger population was most susceptible to metabolic derangements. Further, females were found to be affected more than males. The extremely significant parameters were deranged fasting plasma glucose, HDL, triglycerides while hypertension was found to be insignificant. Being overweight maybe a strong predictor for presence of metabolic syndrome in our region of study, and all overweight persons should be assessed and appropriately treated to prevent future cardiovascular events.

A Study of Carotid Atherosclerosis in Patients with Non-alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease shares many features of metabolic syndrome and its presence could signify a substantial cardiovascular risk above and beyond that conferred by individual risk factors. This study is an attempt to investigate the association of non-alcoholic fatty liver disease with carotid intima-media thickness and plaque as surrogate measures of increased cardiovascular risk. The study was conducted on 645 non diabetic, non alcoholic subjects in the age range of 20-60 years. Metabolic syndrome was assessed by using ATP III and ADA (2005) criteria. Anthropometric factors-waist circumference and blood pressure were measured. Fasting serum samples were analyzed for glucose, triglyceride, cholesterol and its fractions, insulin, alanine and aspartate transaminases, gamma glutamyl transferase and free fatty acids. Insulin resistance and secretion were calculated by homeostasis model and insulin sensitivity by QUICKI index. Liver ultrasonographic scanning was used for assessing fatty liver. Carotid atherosclerosis was assessed by B-mode ultrasonography of common carotid artery and internal carotid artery. The prevalence of non-alcoholic fatty liver disease was 15.6 % in non alcoholic population and 68.5 % of non-alcoholic fatty liver disease had metabolic syndrome, which was associated with hyperinsulinemia, insulin resistance, insulin insensitivity along with elevated levels of waist circumference, blood pressure, triglyceride, FFA and decreased HDL cholesterol. NAFLD patients had markedly greater carotid intima media thickness than non NAFLD subjects with MCIMT of 591.6 ± 108 and 489.5 ± 132.4 μm (P < 0.001) and plaque prevalence of 19.2 and 2.2 %, respectively, thus the carotid intima media thickness is associated with NAFLD.