Influence of hyperglycemia on liver inflammatory conditions in the early phase of non-alcoholic fatty liver disease in mice

Moderate and high-intensity interval training protect against diabetes-induced modulation of hepatic CD86 and CD206 expression associated with the amelioration of insulin resistance and inflammation in rats

Diabetes Mellitus (DM) can damage the function of metabolic tissues, including the liver. Liver macrophages are the first responders to tissue damage or exercise. We sought to determine whether eight weeks of interval training (HIIT & MIIT) protect against diabetes-induced modulation of hepatic CD86 and CD206 expression associated with the amelioration of insulin resistance and inflammation in rats. Thirty rats were divided into six groups, including a control group, MIIT, HIIT, DM, DM + MIIT, and DM + HIIT (n = 5 in each group). Diabetes was induced using a combination of a high-fat diet (HFD) and STZ. Wistar rats in the exercise groups were subjected to moderate and high-intensity interval training for eight weeks. After sample collection, liver tissue was removed and weighed. Serum levels of TNFα, IL-6, TGFβ, and IL-10 were measured by ELISA. Protein expression of the immune markers CD86 and CD206 in liver tissue was determined by immunohistochemical staining. Induction of diabetes increased glycemic indices, insulin resistance, and liver injury enzymes, especially in DM and DM + HIIT groups (p < 0.05). Moreover, diabetic groups showed an increase in liver CD86 protein expression, an increase in TNFα, IL-6, and TGFβ serum levels, and a decrease in liver CD206 and serum IL-10 (p < 0.05). Doing exercise while being diabetic, especially MIIT, significantly reversed the aforementioned factors and reduced insulin resistance (p < 0.05), except IL-10). We concluded that performing exercise training specially MIIT by decreasing CD86 and increasing CD206 in the liver, followed by decreasing pro-inflammatory factors (TNFα, IL-6) caused the regulation of liver enzymes and insulin resistance in diabetic rats. Therefore, it seems that exercise training by regulating macrophage markers CD86 and CD206 can reduce damage to the insulin-signaling pathway by reducing pro-inflammatory cytokines.

Association of post-smoking cessation changes in fasting serum glucose with changes in predicted fatty liver score

Major post-cessation metabolic changes include weight gain and hyperglycemia. However, the association of post-cessation change in fasting serum glucose (FSG) with risk of fatty liver remains unclear. A total of 111,106 participants aged 40 and above who underwent health screening at least once in two examination periods were extracted from the Korean National Health Insurance Service-National Sample Cohort. Fatty liver status was evaluated using the Korean National Health and Nutrition Examination Survey nonalcoholic fatty liver disease (K-NAFLD) score. Linear and logistic regression were used to calculate the adjusted mean (aMean) and adjusted odds ratio (aOR) with 95% confidence intervals. Compared to stable (aMean 0.10; 95% CI 0.03-0.18) and decline (aMean - 0.60; 95% CI - 0.71 to 0.49) groups, FSG elevation (aMean 1.28; 95% CI 1.16-1.39) was associated with higher K-NAFLD score even within different body mass index change groups. Risk of fatty liver was significantly reduced among participants with stable (aOR 0.38; 95% CI 0.31-0.45) and declined (aOR 0.17; 95% CI 0.13-0.22) FSG levels after smoking cessation compared to FSG elevation group. This study suggests that quitters with elevated FSG are associated with higher NAFLD risk and may benefit from careful monitoring of FSG levels and management of other cardiovascular risk factors.

Combinational administration of mesenchymal stem cell-derived exosomes and metformin reduces inflammatory responses in an in vitro model of insulin resistance in HepG2 cells

Diabetes is a highly common metabolic disorder in advanced societies. One of the causes of diabetes is insulin resistance, which is associated with a loss of sensitivity to insulin-sensitive cells. Insulin resistance develops in the body of a person prone to diabetes many years before diabetes development. Insulin resistance is associated with complications such as hyperglycemia, hyperlipidemia, and compensatory hyperinsulinemia and causes liver inflammation, which, if left untreated, can lead to cirrhosis, fibrosis, and even liver cancer. Metformin is the first line of treatment for patients with diabetes, which lowers blood sugar and increases insulin sensitivity by inhibiting gluconeogenesis in liver cells. The use of metformin has side effects, including a metallic taste in the mouth, vomiting, nausea, diarrhea, and upset stomach. For this reason, other treatments, along with metformin, are being developed. Considering the anti-inflammatory role of mesenchymal stem cells (MSCs) derived exosomes, their use seems to help improve liver tissue function and prevent damage caused by inflammation. This study investigated the anti-inflammatory effect of Wharton's jelly MSCs derived exosomes in combination with metformin in the HepG2 cells insulin resistance model induced by high glucose. This study showed that MSCs derived exosomes as an anti-inflammatory agent in combination with metformin could increase the therapeutic efficacy of metformin without needing to change metformin doses by decreasing inflammatory cytokines production, including IL-1, IL-6, and TNF-α and apoptosis in HepG2 cells.

When Sugar Reaches the Liver: Phenotypes of Patients with Diabetes and NAFLD

Type 2 diabetes mellitus (T2DM) and non-alcoholic fatty liver disease (NAFLD) have been traditionally linked to one another. Recent studies suggest that NAFLD may be increasingly common in other types of diabetes such as type 1 diabetes (T1DM) and less frequently ketone-prone and Maturity-onset Diabetes of the Young (MODY) diabetes. In this review, we address the relationship between hyperglycemia and insulin resistance and the onset and progression of NAFLD. In addition, despite the high rate of patients with T2DM and other diabetes phenotypes that can alter liver metabolism and consequently develop steatosis, fibrosis, and cirrhosis, NALFD screening is not still implemented in the daily care routine. Incorporating a clinical algorithm created around a simple, non-invasive, cost-effective model would identify high-risk patients. The principle behind managing these patients is to improve insulin resistance and hyperglycemia states with lifestyle changes, weight loss, and new drug therapies.

High prevalence of hepatic steatosis and hepatic fibrosis in patients with type 2 diabetes mellitus

AIM

To determine the prevalence of hepatic steatosis and fibrosis in patients with T2DM from North India.

RESEARCH DESIGN AND METHODS

In this cross-sectional study, Asian Indian patients with T2DM (n,250) underwent liver ultrasonography (USG), Fibroscan for assessment of hepatic steatosis (Controlled Attenuation Parameter, CAP) and hepatic fibrosis (Kilopascals, kPa) respectively. Pearson's correlation analysis & logistic regression analysis for significant predictors of hepatic steatosis and fibrosis were done. The cut-off value of liver span was calculated by ROC-AUC analysis.

RESULTS

Grade 3 hepatic steatosis was seen in 213 T2DM patients (85.2%). It was higher in males than females and in those with high BMI values. Any degree of fibrosis and severe fibrosis were seen in 205 (62%) and 46 (18.4%) patients, respectively; these were higher in males, specifically in those with BMI >30 kg/m², and diabetes of a duration more than 5 years. BMI and SGPT were the significant predictors of hepatic steatosis. An increase of 1 unit of BMI above 23 kg/m² led to 19.6 times increased risk of hepatic steatosis in T2DM patients aged 50 years and above. SGOT and GGTP were significant predictors of any degree of hepatic fibrosis. On ROC-AUC analysis, liver span cut-off values of ≥16.4 cms and ≥16.8 cm in males and females respectively, were predictive of hepatic fibrosis.

CONCLUSION

High prevalence of grade 3 hepatic steatosis and hepatic fibrosis needs increased vigilance and corrective lifestyle and pharmacological measures. Asian Indian patients with T2DM and BMI >30 kg/m², with duration of diabetes above 5 years & an ultrasound derived liver span ≥16.4 cms, should be further evaluated for hepatic fibrosis.

Insulin treatment improves liver histopathology and decreases expression of inflammatory and fibrogenic genes in a hyperglycemic, dyslipidemic hamster model of NAFLD

Background

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are highly prevalent comorbidities in patients with Type 2 diabetes. While many of these patients eventually will need treatment with insulin, little is known about the effects of insulin treatment on histopathological parameters and hepatic gene expression in diabetic patients with co-existing NAFLD and NASH. To investigate this further, we evaluated the effects of insulin treatment in NASH diet-fed hamsters with streptozotocin (STZ) -induced hyperglycemia.

Methods

Forty male Syrian hamsters were randomized into four groups (n = 10/group) receiving either a NASH-inducing (high fat, fructose and cholesterol) or control diet (CTRL) for four weeks, after which they were treated with STZ or sham-injected and from week five treated with either vehicle (CTRL, NASH, NASH-STZ) or human insulin (NASH-STZ-HI) for four weeks by continuous s.c. infusion via osmotic minipumps.

Results

NASH-STZ hamsters displayed pronounced hyperglycemia, dyslipidemia and more severe liver pathology compared to both CTRL and NASH groups. Insulin treatment attenuated dyslipidemia in NASH-STZ-HI hamsters and liver pathology was considerably improved compared to the NASH-STZ group, with prevention/reversal of hepatic steatosis, hepatic inflammation and stellate cell activation. In addition, expression of inflammatory and fibrotic genes was decreased compared to the NASH-STZ group.

Conclusions

These results suggest that hyperglycemia is important for development of inflammation and profibrotic processes in the liver, and that insulin administration has beneficial effects on liver pathology and expression of genes related to inflammation and fibrosis in a hyperglycemic, dyslipidemic hamster model of NAFLD.

The Association between Hepatic Encephalopathy and Diabetic Encephalopathy: The Brain-Liver Axis

Hepatic encephalopathy (HE) is one of the main consequences of liver disease and is observed in severe liver failure and cirrhosis. Recent studies have provided significant evidence that HE shows several neurological symptoms including depressive mood, cognitive dysfunction, impaired circadian rhythm, and attention deficits as well as motor disturbance. Liver disease is also a risk factor for the development of diabetes mellitus. Diabetic encephalopathy (DE) is characterized by cognitive dysfunction and motor impairment. Recent research investigated the relationship between metabolic changes and the pathogenesis of neurological disease, indicating the importance between metabolic organs and the brain. Given that a diverse number of metabolites and changes in the brain contribute to neurologic dysfunction, HE and DE are emerging types of neurologic disease. Here, we review significant evidence of the association between HE and DE, and summarise the common risk factors. This review may provide promising therapeutic information and help to design a future metabolic organ-related study in relation to HE and DE.

Critical Review on the Presence of Phthalates in Food and Evidence of Their Biological Impact

Phthalates are a huge class of chemicals with a wide spectrum of industrial uses, from the manufacture of plastics to food contact applications, children's toys, and medical devices. People and animals can be exposed through different routes (i.e., ingestion, inhalation, dermal, or iatrogenic exposure), as these compounds can be easily released from plastics to water, food, soil, air, making them ubiquitous environmental contaminants. In the last decades, phthalates and their metabolites have proven to be of concern, particularly in products for pregnant women or children. Moreover, many authors reported high concentrations of phthalates in soft drinks, mineral waters, wine, oil, ready-to-eat meals, and other products, as a possible consequence of their accumulation along the food production chain and their accidental release from packaging materials. However, due to their different physical and chemical properties, phthalates do not have the same human and environmental impacts and their association to several human diseases is still under debate. In this review we provide an overview of phthalate toxicity, pointing out the health and legal issues related to their occurrence in several types of food and beverage.

Could phthalates exposure contribute to the development of metabolic syndrome and liver disease in humans?

In the study, 305 patients of both genders were enrolled and divided into three groups: obese (BMI > 30 kg/m²), patients who were diagnosed type 2 diabetes mellitus (T2DM), and control, normal weight healthy volunteers. At least one of ten different phthalate metabolites was determined in the urine samples of 49.84% all enrolled participants. In the obese subgroup, the sum of all urinary phthalate metabolites was positively associated with TG levels (p = 0.031) together with derived TC/HDL and TG/HDL ratios (p = 0.023 and 0.015), respectively. Urinary MEP concentration was positively correlated with the HOMA-IR in T2DM subgroup (p = 0.016) while in the control subgroup, log₁₀MEP levels were negatively correlated with total cholesterol (p = 0.0051), and LDL serum levels (p = 0.0015), respectively. Also, in the control subgroup, positive linear correlations between urinary log₁₀MEP levels and TyG and TYG-BMI values (p = 0.028 and p = 0.027), respectively, were determined. Urinary MEHP levels were associated with glucose serum levels (p = 0.02) in T2DM subgroup, while in the control HDL values were negatively associated with log₁₀MEHP (p = 0.0035). Healthy volunteers exposed to phthalates had elevated AST levels in comparison to non-exposed ones (p = 0.023). In control subgroup, ALT and AST values were increased (p = 0.02 and p = 0.01, respectively) in MEP exposed while GGT levels were enhanced (p = 0.017) in MEHP exposed in comparison with non-exposed. Combined phthalates influence on glucose and lipid metabolism may increase the possibility for NAFLD and insulin resistance development among exposed individuals.

Gut microbiota dysbiosis correlates with a low-dose PCB126-induced dyslipidemia and non-alcoholic fatty liver disease

There is growing evidence that polychlorinated biphenyl 126 (PCB126) not only has adverse effects on host health but also has the ability to shift gut microbiota, which is recently recognized as a crucial factor determining numerous physiological processes. However, the interplay between the gut microbiota and host health remains largely unknown. Herein, adult female C57BL/6 mice were orally exposed to environmentally relevant low-dose of PCB126, at 50 μg/kg body weight once per week for 6 weeks. This study aims to illuminate how PCB126 influences gut microbiota variations and host disorders and to further identify the correlation between the gut microbiota and metabolic markers of host disorders. Obtained results demonstrated that the PCB126 administration induced gut microbiota dysbiosis in mice, with changes both in the gut microbiota constitution and structure. PCB126 administration also simultaneously altered the physiological status of serum and liver, as evaluated by dyslipidemia, liver lipid accumulation and injury, and non-alcoholic fatty liver disease. Importantly, Spearman's correlation analysis suggested that several specific bacterial taxa were positively and significantly related to metabolic markers of the mentioned disorders. Moreover, based on the co-occurrence network map, some of the bacterial taxa may synergistically regulate host physiology. This work provides new insight into the mechanism underlying the interaction between the gut microbiota and host disorders. It is expected that gut microbiota modulation should be another novel way used for the prevention and treatment of PCB126-triggered diseases.

DHA supplementation prevent the progression of NASH via GPR120 signaling

Nonalcoholic steatohepatitis (NASH) is one of the most common liver diseases involving chronic accumulation of fat and inflammation, often leading to advanced fibrosis, cirrhosis and carcinoma. However, the pathological mechanism for this is unknown. GPR120/FFAR4 has been recognized as a functional fatty acid receptor and an attractive therapeutic target for metabolic diseases. In this study, we investigated the involvement of GPR120/FFAR4 in the pathogenesis of NASH. Mice fed with a 0.1% methionine and choline deficient high-fat (CDAHF) diet showed a significant increase in plasma aspartate transaminase and alanine transaminase levels, fatty deposition, inflammatory cell infiltration, and mild fibrosis. Docosahexaenoic acid (DHA, GPR120/FFAR4 agonist) suppressed the inflammatory cytokines in the liver tissues and prevented fibrosis in the wild type (WT) mice fed CDAHF diet, but not GPR120/FFAR4 deficient (GPR120KO) mice. GPR120KO mice fed CDAHF diet showed increment of the number of crown like structures and the immunoreactivity for F4/80 positive cells, and increased TNF-α mRNA in the liver compared to WT mice fed CDAHF diet. GPR120 KO mice fed CDAHF diet showed more severe liver inflammation than that of WT mice fed CDAHF diet, but not fibrosis. Our findings suggest that DHA supplementation could be prevented the development of NASH via GPR120/FFAR4 signaling. Furthermore, decrease of GPR120/FFAR4 signaling could be facilitated an inflammatory response in the process of NASH progression.

Interactive effects of chronic stress and a high-sucrose diet on nonalcoholic fatty liver in young adult male rats

Glucocorticoids have been implicated in nonalcoholic fatty liver diseases (NAFLD). The influence of a palatable diet on the response to stress is controversial. This study explored whether a high-sucrose diet could protect from hepatic steatosis induced by chronic restraint stress in young adult rats. Male Wistar rats aged 21 days were allocated into four groups (n = 6-8 per group): control, chronic restraint stress, 30% sucrose diet, and 30% sucrose diet plus chronic restraint stress. After being exposed to either tap water or sucrose solution during eight weeks, half of the rats belonging to each group were subject or not to repeated restraint stress (1 h per day, 5 days per week) during four weeks. Triacylglycerol (TAG), oxidative stress, activity of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD-1), infiltration of immune cells, and glycogen amount in the liver were quantified. Serum concentrations of corticosterone and testosterone were also measured. The stressed group showed normal serum concentrations of corticosterone and did not have hepatic steatosis. However, this group showed increased glycogen, inflammation, mild fibrosis, oxidative stress, and a high activity of 11β-HSD-1 in the liver. The group exposed to the high-sucrose diet had lower concentrations of corticosterone, hepatic steatosis and moderate fibrosis. The group subject to high-sucrose diet plus chronic restraint stress showed low concentrations of corticosterone, hepatic steatosis, oxidative stress, and high concentrations of testosterone. Thus, restraint stress and a high-sucrose diet each generate different components of nonalcoholic fatty liver in young adult rats. The combination of both the factors could promote a faster development of NAFLD.