Non-alcoholic Fatty Liver Disease: A Review of Anti-diabetic Pharmacologic Therapies

The Triad of Risk: Linking MASLD, Cardiovascular Disease and Type 2 Diabetes; From Pathophysiology to Treatment

Metabolic dysfunction-associated steatotic liver disease (MASLD) is an emerging global health concern, and it is not only the keystone precursor of eventual liver-related morbidity, but it also places patients at considerably higher cardiovascular risk, which is still a leading cause of death in these patients. The most important common underlying pathophysiological mechanisms in these diseases are primarily related to insulin resistance, chronic inflammation and oxidative stress. The presence of MASLD with cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM) elevates the risk for poor outcomes, thus this review highlights a method to the therapeutic approaches. Given the intertwined nature of MASLD, T2DM, and CVD, there is an urgent need for therapeutic strategies that address all three conditions. Although lifestyle changes are important as treatment, medication plays a crucial role in managing hyperglycemia, enhancing liver function and lowering cardiovascular risk. The onset and progression of MASLD should be addressed through a multifaceted therapeutic approach, targeting inflammatory, immune, metabolic, oxidative stress, hormonal and gutaxis pathways, alongside the treatment strategies for T2DM. In this review, we discuss the effects of antidiabetic drugs with an impact on both liver outcomes and cardiovascular risk in patients affected by MASLD, T2DM and CDV.

Efficacy and Safety of GLP-1 Receptor Agonists in Patients With Metabolic Dysfunction-Associated Steatotic Liver Disease: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Metabolic dysfunction-associated steatotic liver disease (MASLD) poses a major global health challenge. glucagon-like peptide-1 receptor agonists (GLP-1RAs) have shown potential therapeutic benefits for MASLD patients, including improvements in liver function, inflammation, and fibrosis. This study aims to systematically review and meta-analyze randomized controlled trials (RCTs) to evaluate the efficacy and safety of GLP-1RAs in MASLD patients, focusing on hepatic outcomes, cardiovascular outcomes, anthropometric measurements, and mortality. Following PRISMA guidelines, a comprehensive database search was conducted to include RCTs assessing GLP-1RAs' effects on MASLD. Quality assessment was conducted using the Revised Cochrane Risk of Bias tool. Our meta-analysis used a random-effects model, calculating standardized mean differences for continuous outcomes to determine the agents' efficacy and safety. Additionally, funnel plots were generated to assess publication bias, ensuring the integrity of our meta-analytical findings. The review included 27 trials, revealing GLP-1RAs significantly improved hepatic function markers (alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, and liver fat content) and cardiovascular risk factors (fasting blood sugar, HbA1c levels, lipid profiles). Additionally, GLP-1RAs were associated with significant reductions in body weight, BMI, subcutaneous fat, and waist circumference. GLP-1RAs demonstrate a promising therapeutic role in managing MASLD, offering benefits that extend to improving liver function, mitigating cardiovascular risk, and promoting weight loss. Further research is needed to confirm these findings and optimize GLP-1RAs' usage in MASLD treatment.

NON-ALCOHOLIC FATTY LIVER DISEASE AND EXTRA-HEPATIC CANCER: A NARRATIVE REVIEW

BACKGROUND

Recently, significant associations between non-alcoholic fatty liver disease (NAFLD) and extra-hepatic cancer have been reported.

OBJECTIVE

To carry out a comprehensive review of the current evidence in the literature on the association between NAFLD and extra-hepatic cancer.

METHODS

A narrative literature review was performed through an online search for the MeSH terms "fatty liver" and "cancer" in MEDLINE (via PubMed) and LILACS (via BVS). Original studies that described the impact of NAFLD on different types of extra-hepatic malignancies were included.

RESULTS

After careful analysis, nine prospective cohort studies, one retrospective cohort study, three case-control studies, and three cross-sectional studies were selected.

CONCLUSION

There is consistent evidence on the association between NAFLD and extra-hepatic carcinogenesis, especially in relation to colorectal, gastric, pancreatic, breast, prostate, and bladder cancers.

Effect of ipragliflozin on liver enzymes in type 2 diabetes mellitus: a meta-analysis of randomized controlled trials

INTRODUCTION

Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) is estimated to affect upto 70-80% of people with type 2 diabetes mellitus (T2DM). Although several anti-hyperglycemic drugs have been shown to be effective in such patients, there remains an unmet need for newer drugs. The objective of this meta-analysis was to analyze the effect of ipragliflozin on aspartate aminotransferase (AST), alanine transaminase (ALT), and gamma-glutamyl transpeptidase (GGT) levels in patients with T2DM.

METHODS

A literature search on electronic databases was conducted to identify potential randomized clinical trials (RCT) as per predetermined study selection criteria. Mean difference (MD) was calculated using Cochrane review manager.

RESULTS

Twelve studies were included in the meta-analysis, including 1349 subjects. Compared to the control group, ipragliflozin as a monotherapy showed a significant reduction in levels of ALT at week 12 (p = 0.02) and at week 24 (p = 0.007), GGT at week 12 (p < 0.00001). Ipragliflozin as an add-on therapy showed significant reduction in levels of AST at week 24 (p < 0.00001), ALT at week 12 (p = 0.002), ALT at week 24 (p < 0.00001), and GGT at week 24 (p < 0.00001).

CONCLUSION

Findings suggest the beneficial effects of ipragliflozin on liver enzymes. Further large-scale RCTs are required to confirm ipragliflozin's role for liver-related conditions in T2DM.

Comparison of efficacy of anti-diabetics on non-diabetic NAFLD: A network meta-analysis

Objective: This study aimed to assess the efficacy of currently used anti-diabetic medications in the treatment of non-alcoholic fatty liver disease (NAFLD) without diabetes.

DESIGN

The efficacy of various anti-diabetic medicines on non-alcoholic fatty liver disease in the absence of diabetes was evaluated by searching Pubmed, Embase, Cochrane Library, and Web of Science for randomized controlled trials (RCT) only. The methodological quality was evaluated using the Revised Cochrane risk-of-bias tool for randomized trials (RoB2), and the data were analyzed using Stata software (version 15.1).

RESULTS

All papers published between the time of the pooling and September 2022 were searched. There were a total of 18 randomized controlled studies with a total sample size of 1141 cases. The outcomes of interest included variations in alanine transaminase (ALT) and aspartate transaminase (AST). Rosiglitazone (SUCRA: 100%) and vildagliptin (SUCRA: 99.9%) were the best anti-diabetic medicines to improve ALT and AST, respectively, in patients with NAFLD without diabetes, according to the findings of this network meta-analysis.

CONCLUSION

In accordance with the Network Ranking plot, Rosiglitazone was the best anti-diabetic medicine for improving ALT, and vildagliptin was the best for improving AST in patients with non-diabetic NAFLD.

Comparison of Efficacy of Glimepiride, Alogliptin, and Alogliptin-Pioglitazone as the Initial Periods of Therapy in Patients with Poorly Controlled Type 2 Diabetes Mellitus: An Open-Label, Multicenter, Randomized, Controlled Study

BACKGROUND

The choice of an optimal oral hypoglycemic agent in the initial treatment periods for type 2 diabetes mellitus (T2DM) patients remains difficult and deliberate. We compared the efficacy and safety of glimepiride (GLIM), alogliptin (ALO), and alogliptin-pioglitazone (ALO-PIO) in poorly controlled T2DM patients with drug-naïve or metformin failure.

METHODS

In this three-arm, multicenter, open-label, randomized, controlled trial, poorly controlled T2DM patients were randomized to receive GLIM (n=35), ALO (n=31), or ALO-PIO (n=33) therapy for 24 weeks. The primary endpoint was change in the mean glycosylated hemoglobin (HbA1c) levels at week 24 from baseline. Secondary endpoints were changes in HbA1c level at week 12 from baseline, fasting plasma glucose (FPG) levels, lipid profiles at weeks 12 and 24, and parameters of glycemic variability, assessed by continuous glucose monitoring for 24 weeks.

RESULTS

At weeks 12 and 24, the ALO-PIO group showed significant reduction in HbA1c levels compared to the ALO group (-0.96%±0.17% vs. -0.37%±0.17% at week 12; -1.13%±0.19% vs. -0.18%±0.2% at week 24). The ALO-PIO therapy caused greater reduction in FPG levels and significant increase in high-density lipoprotein cholesterol levels at weeks 12 and 24 than the ALO therapy. Compared to low-dose GLIM therapy, ALO-PIO therapy showed greater improvement in glycemic variability. The adverse events were similar among the three arms.

CONCLUSION

ALO-PIO combination therapy during the early period exerts better glycemic control than ALO monotherapy and excellency in glycemic variability than low-dose sulfonylurea therapy in uncontrolled, drug-naïve or metformin failed T2DM patients.

The Role of STAMP2 in Pathogenesis of Chronic Diseases Focusing on Nonalcoholic Fatty Liver Disease: A Review

Nonalcoholic fatty liver disease (NAFLD) is a major health issue. NAFLD can progress from simple hepatic steatosis to nonalcoholic steatohepatitis (NASH). NASH can progress to cirrhosis or hepatocellular carcinoma. Unfortunately, there is no currently approved pharmacologic therapy for NAFLD patients. The six transmembrane protein of prostate 2 (STAMP2), a metalloreductase involved in iron and copper homeostasis, is well known for its critical role in the coordination of glucose/lipid metabolism and inflammation in metabolic tissues. We previously demonstrated that hepatic STAMP2 could be a suitable therapeutic target for NAFLD. In this review, we discuss the emerging role of STAMP2 in the dysregulation of iron metabolism events leading to NAFLD and suggest therapeutic strategies targeting STAMP2.

Impact of sodium glucose cotransporter-2 inhibitors on liver steatosis/fibrosis/inflammation and redox balance in non-alcoholic fatty liver disease

BACKGROUND

Sodium glucose cotransporter-2 inhibitors (SGLT2-I) are the most recently approved drugs for type 2 diabetes (T2D). Recent clinical trials of these compounds reported beneficial cardiovascular (CV) and renal outcomes. A major cause of vascular dysfunction and CV disease in diabetes is hyperglycemia associated with inflammation and oxidative stress. Pre-clinical studies demonstrated that SGLT2-I reduce glucotoxicity and promote anti-inflammatory effects by lowering oxidative stress.

AIM

To investigate the effects of SGLT2-I on markers of oxidative stress, inflammation, liver steatosis, and fibrosis in patients of T2D with non-alcoholic fatty liver disease (NAFLD).

METHODS

We referred fifty-two consecutive outpatients treated with metformin monotherapy and exhibiting poor glycemic control to our centre. We introduced the outpatients to an SGLT2-I (dapagliflozin, empagliflozin, or canagliflozin; n = 26) or a different hypoglycemic drug [other glucose-lowering drugs (OTHER), n = 26]. We evaluated circulating interleukins and serum hydroxynonenal (HNE)- or malondialdehyde (MDA)-protein adducts, fatty liver index (FLI), NAFLD fibrosis score, aspartate aminotransferase (AST)/alanine aminotransferase (ALT) ratio, AST-to-platelet-ratio index (APRI), and fibrosis-4 on the day before (T0) and following treatment for six months (T1). We also performed transient elastography at T0 and T1.

RESULTS

Add-on therapy resulted in improved glycemic control and reduced fasting blood glucose in both groups. Of note, following treatment for six months, a reduction of FLI and APRI, as well as of the FibroScan result, was reported in patients treated with SGLT2-I, but not in the OTHER group; furthermore, in the SGLT2-I group, we reported lower circulating levels of interleukin (IL)-1β, IL-6, tumor necrosis factor, vascular endothelial growth factor, and monocyte chemoattractant protein-1, and higher levels of IL-4 and IL-10. We did not observe any modification in circulating interleukins in the OTHER group. Finally, serum HNE- and MDA-protein adducts decreased significantly in SGLT2-I rather than OTHER patients and correlated with liver steatosis and fibrosis scores.

CONCLUSION

The present data indicate that treatment with SGLT2-I in patients with T2D and NAFLD is associated with improvement of liver steatosis and fibrosis markers and circulating pro-inflammatory and redox status, more than optimizing glycemic control.

Discovery of dipeptidyl peptidase-4 inhibitor specific biomarker in NAFLD mouse models using modified basket trial

Background/Aims

We aimed to define an optimal target population and drug-specific biomarkers that may predict dipeptidyl peptidase (DPP)-4 inhibitor responses in non-alcoholic fatty liver disease (NAFLD).

Methods

An exploration study (study I) was performed using three different NAFLD models (basket study design; high-fat diet [HFD], methionine choline-deficient diet [MCD], and high-cholesterol Western diet [WD] models). RNA transcriptome analysis was performed on pre-studied liver tissues to identify biomarkers that could predict the response to DPP-4 inhibitors. In the validation study (study II), the HFD-induced NAFLD model was divided into high and low hepatic insulin-like growth factor binding protein 1 (Igfbp-1) groups based on the pre-study liver biopsy.

Results

DPP-4 inhibitor attenuated the NAFLD activity score and fibrosis stage in the HFD model but not in the WD and MCD models. The overall response rate was 19% across the modified basket NAFLD trial and 42%, 25%, and 0% in the HFD, WD, and MCD models. Hepatic Igfbp-1 expression was higher in the responder group than in the non-responder group in pre-study biopsy samples. In contrast, hepatic Igfbp-1 expression was lower in the responder group than in the non-responder group in the end-study biopsy samples. DPP-4 inhibitor response rates were 83% and 17% in the baseline hepatic high Igfbp-1 and low Igfbp-1 groups, respectively. Hepatic messenger RNA Igfbp-1 expression was positively correlated with serum IGFBP-1 levels.

Conclusions

The DPP-4 inhibitor response was higher in the HFD phenotype and pre-treatment levels of hepatic or serum IGFBP-1 were high.

Meta-analysis of the effect of sodium-glucose cotransporter 2 inhibitors on hepatic fibrosis in patients with type 2 diabetes mellitus complicated with non-alcoholic fatty liver disease

AIM

This study aimed to analyze the effects of sodium-glucose cotransporter 2 (SGLT2) inhibitors on the indexes of liver fibrosis in patients with type 2 diabetes mellitus complicated with non-alcoholic fatty liver disease, and also to observe the effects on liver enzymes and liver fat.

METHODS

This meta-analysis was performed using RevMan 5.3 statistical software.

RESULTS

SGLT2 inhibitors could significantly reduce the level of hepatic fibrosis index: fibrosis-4 (mean difference [MD] 0.25, 95% CI -0.39 to -0.11, p = 0.0007); serum type Ⅳ collagen 7s (MD 0.32, 95% CI -0.59 to -0.04, p = 0.02); and ferritin (MD 26.7, 95% CI 50.64, 2.76, p = 0.03). SGLT2 inhibitors could significantly reduce the level of liver enzymes: alanine aminotransferase (MD 3.49, 95% CI -5.1 to 1.58, p < 0.0001); aspartate aminotransferase (MD 3.64, 95% CI -5.10 to -2.18, p < 0.00001); and glutamate aminotransferase (MD 7.13, 95% CI -12.95 to -1.32, p = 0.02). SGLT2 inhibitors could significantly reduce the level of liver fat: liver-to-spleen attenuation ratio (MD 0.16, 95% CI 0.10-0.22, p < 0.00001); magnetic resonance imaging proton density fat fraction (MD 1.97, 95% CI -3.49 to -0.45, p = 0.01); liver controlled attenuation parameter (MD 0.29, 95% CI -26.95 to -13.64, p < 0.00001); liver fat score (MD 0.55, 95% CI 1.04 to -0.05, p = 0.03); and liver fat index (MD 11.21, 95% CI -16.53 to -5.89, p < 0.0001).

CONCLUSION

SGLT2 inhibitors could improve liver fibrosis, liver enzymes, liver fat, and metabolic indexes in patients with type 2 diabetes mellitus complicated with non-alcoholic fatty liver disease.

The Evaluation of Drug Delivery Nanocarrier Development and Pharmacological Briefing for Metabolic-Associated Fatty Liver Disease (MAFLD): An Update

Current research indicates that the next silent epidemic will be linked to chronic liver diseases, specifically non-alcoholic fatty liver disease (NAFLD), which was renamed as metabolic-associated fatty liver disease (MAFLD) in 2020. Globally, MAFLD mortality is on the rise. The etiology of MAFLD is multifactorial and still incompletely understood, but includes the accumulation of intrahepatic lipids, alterations in energy metabolism, insulin resistance, and inflammatory processes. The available MAFLD treatment, therefore, relies on improving the patient's lifestyle and multidisciplinary pharmacotherapeutic options, whereas the option of surgery is useless without managing the comorbidities of the MAFLD. Nanotechnology is an emerging approach addressing MAFLD, where nanoformulations are suggested to improve the safety and physicochemical properties of conventional drugs/herbal medicines, physical, chemical, and physiological stability, and liver-targeting properties. A wide variety of liver nanosystems were constructed and delivered to the liver, only those that addressed the MAFLD were discussed in this review in terms of the nanocarrier classes, particle size, shape, zeta potential and offered dissolution rate(s), the suitable preparation method(s), excipients (with synergistic effects), and the suitable drug/compound for loading. The advantages and challenges of each nanocarrier and the focus on potential promising perspectives in the production of MAFLD nanomedicine were also highlighted.

Berberine inhibits liver damage in rats with non-alcoholic fatty liver disease by regulating TLR4/MyD88/NF-κB pathway

BACKGROUND/AIMS

This study aimed to explore the therapeutic effects and underlying mechanism of berberine (BBR) on the non-alcoholic fatty liver disease (NAFLD) induced by high-fat diet (HFD).

MATERIALS AND METHODS

Rats were randomly divided into the following 4 groups: control (normal diet), model (HFD), polyene phosphatidylcholine HFD+PPC, and BBR (HFD+BBR) group. The NAFLD models were prepared by feeding with HFD for 12 weeks. The liver tissues were observed by oil red O staining. H-E staining was used to detect pathological changes in the liver tissues. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) were detected by an automatic biochemical analyzer. ELISA was performed to observe the inflammatory cytokines (TNF-α, IL-6, and IL-1β) expressions. The levels of TLR4, MyD88, and NF-κB p65 were analyzed using western blot and qRT-PCR, respectively. The nuclear translocation levels of NF-κB in the primary liver cells were measured using flow cytometry.

RESULTS

BBR could significantly alleviate the liver tissue steatosis and inflammatory cell infiltration; reduce the NAFLD activity scores and serum levels of ALT, AST, TC, and LDL-C; decrease the levels of TNF-α, IL-6, and IL-1β, and reduce the expression of TLR4, MyD88, and NF-κB in the liver tissues. BBR could also reverse the nuclear translocation of NF-κB in the primary liver cells.

CONCLUSION

BBR alleviated the progress of NAFLD and liver damage, which might contribute to inhibit the nuclear translocation of NF-κB via the TLR4/MyD88/NF-κB pathway.

Liver Fibrosis in Non-alcoholic Fatty Liver Disease: From Liver Biopsy to Non-invasive Biomarkers in Diagnosis and Treatment

An increasing percentage of people have or are at risk to develop non-alcoholic fatty liver disease (NAFLD) worldwide. NAFLD comprises different stadia going from isolated steatosis to non-alcoholic steatohepatitis (NASH). NASH is a chronic state of liver inflammation that leads to the transformation of hepatic stellate cells to myofibroblasts. These cells produce extra-cellular matrix that results in liver fibrosis. In a normal situation, fibrogenesis is a wound healing process that preserves tissue integrity. However, sustained and progressive fibrosis can become pathogenic. This process takes many years and is often asymptomatic. Therefore, patients usually present themselves with end-stage liver disease e.g., liver cirrhosis, decompensated liver disease or even hepatocellular carcinoma. Fibrosis has also been identified as the most important predictor of prognosis in patients with NAFLD. Currently, only a minority of patients with liver fibrosis are identified to be at risk and hence referred for treatment. This is not only because the disease is largely asymptomatic, but also due to the fact that currently liver biopsy is still the golden standard for accurate detection of liver fibrosis. However, performing a liver biopsy harbors some risks and requires resources and expertise, hence is not applicable in every clinical setting and is unsuitable for screening. Consequently, different non-invasive diagnostic tools, mainly based on analysis of blood or other specimens or based on imaging have been developed or are in development. In this review, we will first give an overview of the pathogenic mechanisms of the evolution from isolated steatosis to fibrosis. This serves as the basis for the subsequent discussion of the current and future diagnostic biomarkers and anti-fibrotic drugs.

Adipose tissue in health and disease

Adipose, or fat, tissue (AT) was once considered an inert tissue that primarily existed to store lipids, and was not historically recognized as an important organ in the regulation and maintenance of health. With the rise of obesity and more rigorous research, AT is now recognized as a highly complex metabolic organ involved in a host of important physiological functions, including glucose homeostasis and a multitude of endocrine capabilities. AT dysfunction has been implicated in several disease states, most notably obesity, metabolic syndrome and type 2 diabetes. The study of AT has provided useful insight in developing strategies to combat these highly prevalent metabolic diseases. This review highlights the major functions of adipose tissue and the consequences that can occur when disruption of these functions leads to systemic metabolic dysfunction.

SGLT2 inhibitors in patients with type 2 diabetes with non-alcoholic fatty liver diseases: an umbrella review of systematic reviews

INTRODUCTION

Sodium glucose co-transporter 2 (SGLT2) inhibitors have been reported to benefit liver functions in patients with type 2 diabetes (T2D) with non-alcoholic fatty liver disease (NAFLD). The aim of this study is to critically appraise existing systematic reviews in order to consolidate evidence associating the use of SGLT2 inhibitors with beneficial hepatic results for patients with T2D with NAFLD.

METHODS

This umbrella review searched relevant published systematic reviews of clinical trials from PubMed and Embase between inception and September 16, 2020. Two independent investigators appraised study quality using AMSTAR2 (Assessment of Multiple Systematic Reviews 2). The hepatic effects from SGLT2 inhibitors were summarized based on liver enzymes, liver fat, liver histology, liver cirrhosis and liver cancer.

RESULTS

Of 25 screened potential systematic reviews, we ultimately included 7 in this study. However, none of them could be rated as being of high methodological quality. Five systematic reviews indicated that SGLT2 inhibitors could effectively decrease liver fat and liver parameters of alanine aminotransferase and gamma-glutamyl transferase in patients with NAFLD. Two systematic reviews indicated that SGLT2 inhibitors could reduce hepatosteatosis, as supported by biopsy-proven evidence of improvement from a small clinical trial, but no evidence of liver fibrosis improvement was found.

CONCLUSIONS

There is some association between SGLT2 inhibitor use and observed benefits to liver functions in patients with T2D with NAFLD, although the quality of current systematic reviews remains relatively low. Further evaluation of long-term liver outcomes with SGLT2 inhibitors in cases of liver cirrhosis and liver cancer is warranted.

Metabolic Syndrome and Abnormal Peri-Organ or Intra-Organ Fat (APIFat) Deposition in Chronic Obstructive Pulmonary Disease: An Overview

Chronic obstructive pulmonary disease (COPD) is a common disorder with an increasing prevalence, characterised by persistent respiratory symptoms and airflow limitation. Systemic inflammation is involved in the pathogenesis of COPD and can also predispose to metabolic disorders (e.g., metabolic syndrome (MetS) and non-alcoholic fatty liver disease (NAFLD)). Such comorbidities can negatively affect COPD outcomes, cardiovascular risk, and quality of life. Apart from NAFLD, abnormal peri-organ or intra-organ fat (APIFat) could be considered as markers for cardiometabolic diseases and even for COPD. The present narrative review considers the associations of COPD with MetS, NAFLD, and other APIFat, including epicardial, perirenal, peripancreatic, and intramuscular adipose tissue. Further research is needed to define these relationships and identify any potential clinical implications.

Post-transplant diabetes mellitus and preexisting liver disease - a bidirectional relationship affecting treatment and management

Liver cirrhosis and diabetes mellitus (DM) are both common conditions with significant socioeconomic burden and impact on morbidity and mortality. A bidirectional relationship exists between DM and liver cirrhosis regarding both etiology and disease-related complications. Type 2 DM (T2DM) is a well-recognized risk factor for chronic liver disease and vice-versa, DM may develop as a complication of cirrhosis, irrespective of its etiology. Liver transplantation (LT) represents an important treatment option for patients with end-stage liver disease due to non-alcoholic fatty liver disease (NAFLD), which represents a hepatic manifestation of metabolic syndrome and a common complication of T2DM. The metabolic risk factors including immunosuppressive drugs, can contribute to persistent or de novo development of DM and NAFLD after LT. T2DM, obesity, cardiovascular morbidities and renal impairment, frequently associated with metabolic syndrome and NAFLD, may have negative impact on short and long-term outcomes following LT. The treatment of DM in the context of chronic liver disease and post-transplant is challenging, but new emerging therapies such as glucagon-like peptide-1 receptor agonists (GLP-1RAs) and sodium–glucose cotransporter 2 inhibitors (SGLT2i) targeting multiple mechanisms in the shared pathophysiology of disorders such as oxidative stress and chronic inflammation are a promising tool in future patient management.

Ghrelin regulates adipose tissue metabolism: Role in hepatic steatosis

Fatty liver is the earliest and most common response of the liver to consumption of excessive alcohol. Steatosis can predispose the fatty liver to develop progressive liver damage. Chief among the many mechanisms involved in development of hepatic steatosis is dysregulation of insulin-mediated adipose tissue metabolism. Particularly, it is the enhanced adipose lipolysis-derived free fatty acids and their delivery to the liver that ultimately results in hepatic steatosis. The adipose-liver axis is modulated by hormones, particularly insulin and adiponectin. In recent studies, we demonstrated that an alcohol-induced increase in serum ghrelin levels impairs insulin secretion from pancreatic β-cells. The consequent reduction in circulating insulin levels promotes adipose lipolysis and mobilization of fatty acids to the liver to ultimately contribute to hepatic steatosis. Because many tissues, including adipose tissue, express ghrelin receptor we hypothesized that ghrelin may directly affect energy metabolism in adipocytes. We have exciting new preliminary data which shows that treatment of premature 3T3-L1 adipocytes with ghrelin impairs adipocyte differentiation and inhibits lipid accumulation in the tissue designed to store energy in the form of fat. We further observed that ghrelin treatment of differentiated adipocytes significantly inhibited secretion of adiponectin, a hepatoprotective hormone that reduces lipid synthesis and promotes lipid oxidation. These results were corroborated by our observations of a significant increase in serum adiponectin levels in ethanol-fed rats treated with a ghrelin receptor antagonist verses the un-treated ethanol-fed rats. Interestingly, in adipocytes, ghrelin also increases secretion of interleukin-6 (IL-6) and CCL2 (chemokine [C-C motif] ligand 2), cytokines which promote hepatic inflammation and progression of liver disease. To summarize, the alcohol-induced increase in serum ghrelin levels dysregulates adipose-liver interaction and promotes hepatic steatosis by increasing the free fatty acid released from adipose for hepatic uptake, and by altering adiponectin and cytokine secretion. Taken together, our data indicates that targeting the activity of ghrelin may be a powerful treatment strategy.

Practical application of short-term intensive insulin therapy based on the concept of "treat to target" to reduce hypoglycaemia in routine clinical site

The aim is to devise a new short-term intensive insulin therapy (N-SIIT) based on the concept of "treat to target" to avoid hypoglycaemia and was applied it to various diabetic state. We determined dosage of 1 basal and 3 bolus "treat" insulin based on "target" blood glucose level and changed each insulin dose by small units (2 units) every day for 2 weeks. We evaluated the effects of N-SIIT in 74 subjects with type 2 diabetes (male 45, female 29, 64.9 ± 16.6 years old, HbA1c 10.4 ± 2.6%). Glargine U300 ("treat") and morning blood glucose level ("target") was significantly correlated with increasing insulin dose and decreasing blood glucose level in day 1-7, indicating that insulin amount was determined by target blood glucose level and lowered next target blood glucose level. Remission rates were 67.3% (Hypoglycaemia rate 5.6 %) in N-SIIT and 47.3% (Hypoglycaemia rate 38.1%) in conventional SIIT. Required amount of insulin would be automatically determined, depending on each patient pathophysiology and life style. This method is pretty simple, flexible and cheap, and provides information about the dynamic pathophysiological alteration of insulin resistance and glucotoxicity from the profile of blood glucose levels and insulin shot.

Dipeptidyl peptidase-4 inhibition prevents nonalcoholic steatohepatitis-associated liver fibrosis and tumor development in mice independently of its anti-diabetic effects

Nonalcoholic steatohepatitis (NASH) is a hepatic phenotype of the metabolic syndrome, and increases the risk of cirrhosis and hepatocellular carcinoma (HCC). Although increasing evidence points to the therapeutic implications of certain types of anti-diabetic agents in NASH, it remains to be elucidated whether their effects on NASH are independent of their effects on diabetes. Genetically obese melanocortin 4 receptor–deficient (MC4R-KO) mice fed Western diet are a murine model that sequentially develops hepatic steatosis, NASH, and HCC in the presence of obesity and insulin resistance. In this study, we investigated the effect of the dipeptidyl peptidase-4 (DPP-4) inhibitor anagliptin on NASH and HCC development in MC4R-KO mice. Anagliptin treatment effectively prevented inflammation, fibrosis, and carcinogenesis in the liver of MC4R-KO mice. Interestingly, anagliptin only marginally affected body weight, systemic glucose and lipid metabolism, and hepatic steatosis. Histological data and gene expression analysis suggest that anagliptin treatment targets macrophage activation in the liver during the progression from simple steatosis to NASH. As a molecular mechanism underlying anagliptin action, we showed that glucagon-like peptide-1 suppressed proinflammatory and profibrotic phenotypes of macrophages in vitro. This study highlights the glucose metabolism–independent effects of anagliptin on NASH and HCC development.

Effects of (-)-epicatechin on the time course of the expression of perilipins in a diet-induced model of nonalcoholic steatohepatitis

The existing treatments for nonalcoholic steatohepatitis (NASH) are not completely effective. The need for new alternatives without adverse effects and low cost, such as the flavonoid (-)-epicatechin (EC), which has beneficial effects on lipid metabolism and cardiovascular diseases, arises. The objective of this work was to analyze EC effects in the NASH induced by a Paigen-type diet (PD). Mice were administered with (1) normal chow and water, (2) PD + fructose 30% and (3) PD + fructose 30% + EC (1 mg/kg) per gavage during 9 weeks. At the end of each treatment, serum was collected for analysis of the biochemical profile and liver enzymes. The liver was collected for microscopic analysis and for the evaluation of the relative expression of Plin2, Plin3, CD36, adiponectin and UCP2. Results showed that EC reduced weight gain and decreased triglyceride (TG), low-density lipoprotein cholesterol, TG/high-density lipoprotein and the activity of liver enzymes (alanine aminotransferase and alkaline phosphatase), suggesting lower liver damage. The microscopic analysis showed less "balloonization" of the hepatocyte, small drops of lipids, less accumulation of collagen and infiltration of inflammatory cells as compared to nontreated group. Finally, a decrease in the expression of Plin 2 was observed. While CD36 decreased, adiponectin and UCP2 increased. In conclusion, EC improves the biochemical profile, the microscopic characteristics and protein expression. Therefore, it may be a possible therapeutic approach for NASH since it prevents the progression of the hepatic and metabolic damage induced by high-fat diets.

A round trip from nonalcoholic fatty liver disease to diabetes: molecular targets to the rescue?

Evidence suggests a close relationship between nonalcoholic fatty liver disease (NAFLD) and type two diabetes (T2D). On the grounds of prevalence of disease, both conditions account for a significant financial cost for health care systems and individuals. Aim of this review article is to explore the epidemiological basis and the putative molecular mechanisms underlying the association of NAFLD with T2D. Epidemiological studies have shown that NAFLD is associated to the development of incident T2D and either reversal or improvement of NAFLD will result into decreased risk of developing incident T2D. On the other side of the coin data have shown that T2D will worsen the course of NAFLD doubling the risk of disease progression (i.e. evolution from simple steatosis to advanced fibrosis, cirrhosis, hepatocellular carcinoma, liver transplant and death). Conversely, NAFLD will contribute to metabolic decompensation of T2D. The pathogenesis of T2D in NAFLD patients may be mediated by several hepatokines impairing metabolic control. Among these, Fetuin-B, which causes glucose intolerance and is increased in patients with T2D and NAFLD with fibrosis is one of the most promising. T2D may affect the progression of NAFLD by acting at different levels of the pathogenic cascade involving gut microbiota and expanded, inflamed, dysfunctional adipose tissue. In conclusion, T2D and NAFLD are mutually, closely and bi-directionally associated. An improved understanding of molecular pathogenesis underlying this bi-directional association may allow us to be able to prevent the development of T2D by halting the progression of NAFLD.

Identification of 8-miRNAs as biomarkers for nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) poses serious threats to humans. Several studies have studied the biomarkers associated with NAFLD; however, the results vary because of the differences in the sequencing platform, sample selection, and filter conditions. This study aimed to explore the key microRNAs (miRNAs) of NAFLD by a systematic bioinformatics analysis. A total of 10 qualified NAFLD miRNA data sets were selected through a literature review. Signature miRNAs were identified by overlap comparison. The target genes of miRNAs were predicted by TargetScan software and functional enrichment, and transcription factor (TF) binding analysis of target genes was carried out by the database for annotation, visualization, and integrated discovery and Tfacts database, respectively. A total of three upregulated miRNAs and five downregulated miRNAs were identified in the NAFLD tissue. The target genes of upregulated miRNAs mainly enriched in the RNA polymerase II promoter transcriptional regulation, chromatin remodeling process, and O-glycan synthesis, circadian rhythm, and endocytosis; the target genes of downregulated miRNAs mainly enriched in the transcriptional regulation of DNA as a template, negative regulation process of protein phosphorylation, and Fc epsilon RI signaling pathways, Ras signaling pathways and the interaction between cytokines and cytokines. Besides, 136 interactions were formed between 62 TFs and 45 target genes of upregulated miRNA, whereas 157 interactions were formed between 72 TFs and 45 target genes of downregulated miRNA. Both contained 102 TFs, and 32 TFs were present in both target genes. To summarize, we identified an eight-miRNA set as a signature for NAFLD, which will benefit the clinical treatment of NAFLD.

Beneficial effects of SGLT2 inhibitors on fatty liver in type 2 diabetes: A common comorbidity associated with severe complications

Patients with type 2 diabetes mellitus (T2DM) are exposed to non-alcoholic fatty liver disease (NAFLD), a comorbidity associated with cardiovascular disease and chronic kidney disease, and which may progress to non-alcoholic steatohepatitis (NASH), fibrosis and cirrhosis. Sodium-glucose cotransporter type-2 (SGLT2) inhibitors are glucose-lowering agents that improve glucose control while promoting weight loss and lowering serum uric acid levels. These agents may exert cardiovascular and renal protection in T2DM patients with established cardiovascular disease. Recent findings from both randomized controlled trials and open-label studies have also shown that SGLT2 inhibitors are able to reduce fatty liver content, as assessed by different imaging techniques, and improve biological markers of NAFLD, especially serum liver enzymes, in patients with T2DM. In addition, there are emerging data to suggest a mechanism beyond the reduction of hyperglycaemia and body weight, and a potential role for the decrease in low-grade inflammation and oxidative stress associated with SGLT2 inhibitor therapy. This positive effect of SGLT2 inhibitors on NAFLD complements their already well-known effects on cardiovascular and chronic kidney diseases.

Liraglutide Attenuates Nonalcoholic Fatty Liver Disease through Adjusting Lipid Metabolism via SHP1/AMPK Signaling Pathway

A glucagon-like peptide-1 (GLP-1) receptor agonist liraglutide (LR) had been experimentally and clinically shown to ameliorate nonalcoholic fatty liver disease (NAFLD). This study aimed to investigate the beneficial effect of LR on NAFLD in vivo and in vitro and its underlying molecular mechanism. The effects of LR were examined on the high-fat diet-induced in vivo model in mice and in vitro model of NAFLD in human HepG2 cells. Liver tissues and HepG2 cells were procured for measuring lipid metabolism, histological examination, and western blot analysis. LR administration significantly lowered the serum lipid profile and lipid disposition in vitro and in vivo because of the altered expression of enzymes on hepatic gluconeogenesis and lipid metabolism. Moreover, LR significantly decreased Src homology region 2 domain-containing phosphatase-1 (SHP1) and then increased the expression of phosphorylated-AMP-activated protein kinase (p-AMPK). However, the overexpression of SHP1 mediated by lentivirus vector reversed LR-induced improvement in lipid deposition. Moreover, SHP1 silencing could further increase the expression of p-AMPK to ameliorate lipid metabolism and relative lipogenic gene induced by LR. In addition, abrogation of AMPK by Compound C eliminated the protective effects of LR on lipid metabolism without changing the expression of SHP1. LR markedly prevented NAFLD through adjusting lipid metabolism via SHP1/AMPK signaling pathway.

Signaling through non-membrane nuclear phosphoinositide binding proteins in human health and disease

Phosphoinositide membrane signaling is critical for normal physiology, playing well-known roles in diverse human pathologies. The basic mechanisms governing phosphoinositide signaling within the nucleus, however, have remained deeply enigmatic owing to their presence outside the nuclear membranes. Over 40% of nuclear phosphoinositides can exist in this non-membrane state, held soluble in the nucleoplasm by nuclear proteins that remain largely unidentified. Recently, two nuclear proteins responsible for solubilizing phosphoinositides were identified, steroidogenic factor-1 (SF-1; NR5A1) and liver receptor homolog-1 (LRH-1; NR5A2), along with two enzymes that directly remodel these phosphoinositide/protein complexes, phosphatase and tensin homolog (PTEN; MMAC) and inositol polyphosphate multikinase (IPMK; ipk2). These new footholds now permit the assignment of physiological functions for nuclear phosphoinositides in human diseases, such as endometriosis, nonalcoholic fatty liver disease/steatohepatitis, glioblastoma, and hepatocellular carcinoma. The unique nature of nuclear phosphoinositide signaling affords extraordinary clinical opportunities for new biomarkers, diagnostics, and therapeutics. Thus, phosphoinositide biology within the nucleus may represent the next generation of low-hanging fruit for new drugs, not unlike what has occurred for membrane phosphatidylinositol 3-kinase drug development. This review connects recent basic science discoveries in nuclear phosphoinositide signaling to clinical pathologies, with the hope of inspiring development of new therapies.