Novel antidiabetic medications for non-alcoholic fatty liver disease with type 2 diabetes mellitus

Comparative Efficacy of Magnetic Resonance Cholangiopancreatography vs. Percutaneous Transhepatic Cholangiography With Percutaneous Transhepatic Biliary Drainage Stenting in Evaluating Obstructive Jaundice: A Prospective Study in South India

Introduction Obstructive jaundice due to proximal biliary obstruction presents significant diagnostic and therapeutic challenges. Accurate and timely diagnosis is essential for effective management. Objective/aim This study aimed to evaluate and compare the diagnostic accuracy of magnetic resonance cholangiopancreatography (MRCP) and percutaneous transhepatic cholangiography (PTC) along with percutaneous transhepatic biliary drainage (PTBD) stenting in obstructive jaundice, while also incorporating the comparison of ultrasonography (USG) and computed tomography (CT) findings. Materials and methods A prospective study was conducted at a tertiary healthcare center in South India from January 2020 to June 2022. Comprehensive diagnostic evaluations were performed using USG, contrast-enhanced computed tomography (CECT), MRCP, and PTC. The diagnostic outcomes from USG and CECT were initially assessed, followed by MRCP for every patient. These results were then compared with PTC, focusing on identifying the causes and levels of biliary obstruction. Results Fifty patients with suspected obstructive jaundice were included in the study. The study predominantly involved patients aged between the fourth and eighth decades (80%). Choledocholithiasis was identified as the leading cause (30%). MRCP demonstrated superior sensitivity in identifying both the cause (80%) and level (88%) of obstruction. It was particularly effective in detecting hilar masses with 100% sensitivity. Conversely, PTC, while less sensitive in detection, offered the advantage of simultaneous therapeutic intervention through stenting, with a sensitivity rate of 93% in detecting hilar masses. Conclusion MRCP outperforms PTC in diagnostic sensitivity for obstructive jaundice caused by proximal biliary obstruction. However, the advantage of PTC lies in its capacity for immediate therapeutic intervention via stent placement, addressing both diagnostic and treatment needs.

Linalool attenuates lipid accumulation and oxidative stress in metabolic dysfunction-associated steatotic liver disease via Sirt1/Akt/PPRA-α/AMPK and Nrf-2/HO-1 signaling pathways

INTRODUCTION

Linalool is a monoterpene that occurs naturally in various aromatic plants and is identified in our previous study as a potential candidate for protection against high-fat diet (HFD)-induced metabolic dysfunction-associated steatotic liver disease (MASLD). However, little is known about its direct effects on hepatic lipid metabolism and oxidative stress. Therefore, this study aims to investigate the therapeutic effect of linalool against MASLD and the underlying mechanism.

METHODS

To establish a rat model of MASLD, male Wistar rats were fed HFD for 16 weeks and orally administered linalool (100 mg/kg body weight) for 45 days starting from week 14.

RESULTS

Linalool significantly reduced HFD-induced liver lipid accumulation and restored altered adipokine levels. Mechanistically, linalool downregulated the mRNA expression of sterol regulatory element binding protein 1 and its lipogenesis target genes fatty acid synthase and acetyl-CoA carboxylase, and upregulated the mRNA expression of genes involved in fatty acid oxidation (peroxisome proliferator-activated receptor (PPAR)-alpha [PPAR-α], lipoprotein lipase and protein kinase B [Akt]) as well as the upstream mediators sirtuin 1 (Sirt1) and AMP-activated protein kinase (AMPK) in the liver of MASLD rats. In addition, linalool also curbed oxidative stress by increasing antioxidant enzymes and activating nuclear erythroid-2-related factor 2 (Nrf-2) and its downstream target genes involved in antioxidant properties.

CONCLUSION

Therefore, this study concludes that linalool attenuates lipid accumulation in the liver by inhibiting de novo lipogenesis, promoting fatty acid oxidation, and attenuating oxidative stress by regulating Sirt1/Akt/PPRA-α/AMPK and Nrf-2/ HO-1 signaling pathways.

ZSP1601, a novel pan-phosphodiesterase inhibitor for the treatment of NAFLD, A randomized, placebo-controlled phase Ib/IIa trial

Non-alcoholic fatty liver disease is a growing health burden with limited treatment options worldwide. Herein we report a randomized, double-blind, placebo-controlled, multiple-dose trial of a first-in-class pan-phosphodiesterase inhibitor ZSP1601 in 36 NAFLD patients (NCT04140123). There were three cohorts. Each cohort included twelve patients, nine of whom received ZSP1601 50 mg once daily, 50 mg twice daily, or 100 mg twice daily, and three of whom received matching placebos for 28 days. The primary outcomes were the safety and tolerability of ZSP1601. A total of 27 (27/36, 75%) patients experienced at least one treatment-emergent adverse event (TEAE). Most TEAEs were mild to moderate. There was no Serious Adverse Event. Diarrhea, transiently elevated creatinine and adaptive headache were frequently reported adverse drug reaction. We conclude that ZSP1601 is well-tolerated and safe, showing effective improvement in liver chemistries, liver fat content and fibrosis in patients with NAFLD.

[Clinical effectiveness and pharmacokinetics of gliflozin from the point of view of individual genetic characteristics: A review]

A review of publications devoted to the analysis of genetic polymorphisms and features of the functioning of genes that affect the pharmacokinetics and pharmacodynamics of sodium-glucose cotransporter-2 inhibitors (SGLT2i) is presented. Objective of the study was to reveal information about genes whose polymorphism may affect the effectiveness of SGLT2i. The review was carried out in accordance with the PRISMA 2020 recommendations, the search for publications was carried out in the PubMed databases (including Medline), Web of Science, as well as Russian scientific electronic libraries eLIBRARY.RU from 1993 to 2022. Polymorphisms in the structure of several genes (SLC5A2, UGT1A9, ABCB1, PNPLA3) have been described that may affect the treatment of type 2 diabetes mellitus complicated by diseases such as chronic heart failure, chronic kidney disease, or non-alcoholic fatty liver disease. The information found on the genetic features of the development of the effects of SGLT2i is limited to a description of the differences in their pharmacokinetics. The relevance of currently available pharmacogenetic studies is largely constrained by small sample sizes.

Effect and Safety of Pioglitazone-Metformin Tablets in the Treatment of Newly Diagnosed Type 2 Diabetes Patients with Nonalcoholic Fatty Liver Disease in Shaanxi Province: A Randomized, Double-Blinded, Double-Simulated Multicenter Study

Objective

The aim of study was to evaluate the effect and safety of pioglitazone-metformin combined treatment in the newly diagnosed type 2 diabetes patients with nonalcoholic fatty liver disease.

Methods

A total of 120 newly diagnosed type 2 diabetes patients with nonalcoholic fatty liver disease from 8 centers were randomly divided into the control group (metformin hydrochloride) and the test group (pioglitazone hydrochloride and metformin hydrochloride).

Results

Compared to the control group, after treatment, the proportion of people with mild and moderate fatty liver increased, and the proportion of people with severe fatty liver decreased, and this change was more obvious in the population with moderate and severe fatty liver. The level of γ-GT decreased in both groups before and after treatment, which was statistically significant, and there was also a statistically significant difference in the level of γ-GT between the two groups after 24 weeks. There were no significant statistically differences in blood lipid, body weight, and waist circumference between the test group and the control group. Logistic regression analysis found that BMI is one of the risk factors for fatty liver. There was also no significant difference in the incidence of serious adverse events between the two groups (control group: 10.00% and test group: 6.67%, P = 0.74).

Conclusion

Combined treatment with pioglitazone-metformin can effectively reduce liver fat content and gamma-GT level in newly diagnosed diabetic patients with nonalcoholic fatty liver disease, and adverse events do not increase compared with the control group, showing good safety and tolerance. This trial is registered with ClinicalTrials.gov NCT03796975.

Association of Dipeptidyl Peptidase-4 Inhibitors Use with Reduced Risk of Hepatocellular Carcinoma in Type 2 Diabetes Patients with Chronic HBV Infection

Previous studies have indicated that HBV infection and T2DM are the factors that increase the risk of developing HCC. The experimental evidence has shown that antiglycemic agents may reduce the risk of HCC. However, the effect of dipeptidyl peptidase-4 inhibitors (DPP-4 inhibitors) on the risk of HCC in T2DM patients with chronic HBV infection remains unclear. In this retrospective cohort study, we extracted patients with T2DM and chronic HBV infection from the National Health Insurance Research Database (NHIRD) in Taiwan. The cases were divided into DPP-4 inhibitors use and non-use groups, according to whether they received DPP-4 inhibitors treatment, and the risk of HCC was compared between the two groups. At the end of the follow-up, approximately 2.33% of DPP-4 inhibitors users had received an HCC diagnosis compared with 3.33% of non-DPP-4 inhibitors users (p < 0.0001). After multivariate adjustment, DPP-4 inhibitors users showed a significant reduction in HCC risk (adjusted hazard ratios (aHRs): 0.53; 95% confidence intervals (CIs): 0.44-0.65). In conclusion, this population-based retrospective cohort study indicated that, in T2DM patients with chronic HBV infection, the use of DPP-4 inhibitors significantly reduced the risk of developing HCC compared with non-DPP-4 inhibitors use.

Comparative efficacy of diabetes medications on liver enzymes and fat fraction in patients with nonalcoholic fatty liver disease: A network meta-analysis,

OBJECTIVES

This network meta-analysis (NMA) aimed to evaluate the relative rank-order of existing diabetes medications in patients with nonalcoholic fatty liver disease (NAFLD) with or without type 2 diabetes mellitus (T2DM).

METHODS

A systematic literature search was conducted using the Medline, Embase and Cochrane databases. Clinical trials comparing the efficacy of diabetes medications with other interventions, including lifestyle modification and placebo, in patients with NAFLD were included. The results from the NMA are presented as the weighted mean difference (WMD) of the continuous results and the corresponding 95% confidence intervals (95% CIs).

RESULTS

The articles presented the results of 49 trials involving 3,836 subjects published between 2013 and 2021. According to our results, thiazolidinedione (TZD) was ranked as the best diabetes medication in the reduction of alanine aminotransferase (ALT) (WMD = -10.10, 95% CI: -15.18, -5.01), followed by dipeptidyl peptidase-4 inhibitor (DPP4i) (WMD = -8.90, 95% CI: -14.41, -3.40). DPP4i also resulted in the greatest reduction in aspartate aminotransferase (AST) (WMD = -6.89, 95% CI: -11.72, -2.07). γ-Glutamyl transferase (γ-GT) reduction was highest in patients treated with glucagon-like peptide 1 receptor agonists (GLP1RAs) (WMD = -15.48, 95% CI: -30.93, -0.02). Ultimately, SGLT2is and GLP1RAs were superior to other diabetes medications or placebo in reducing liver fat fraction (LFF) (WMD = -6.09, 95% CI: -10.50, -1.68; WMD = -5.55, 95% CI: -10.40, -0.69, respectively).

CONCLUSION

Diabetes medications, including TZD, DPP4i and GLP1RAs, were found to be suitable alternatives for liver enzyme reduction in the treatment of NAFLD patients. SGLT2is are considered the most effective therapies for lipid modulation in these patients.

Personalizing Diabetes Management in Liver Transplant Recipients: The New Era for Optimizing Risk Management

Post-transplant diabetes mellitus (PTDM) is a significant contributor to morbidity and mortality in liver transplant recipients (LTRs). With concurrent comorbidities and use of various immunosuppression medications, identifying a safe and personalized regimen for management of PTDM is needed. There are many comorbidities associated with the post-transplant course including chronic kidney disease, cardiovascular disease, allograft steatosis, obesity, and de novo malignancy. Emerging data suggest that available diabetes medications may carry beneficial or, in some cases, harmful effects in the setting of these co-existing conditions. Sodium-glucose co-transporter 2 inhibitors and glucagon-like peptide 1 receptor agonists have shown the most promising beneficial results. Although there is a deficiency of LTR-specific data, they appear to be generally safe. Effects of other medications are varied. Metformin may reduce the risk of malignancy. Pioglitazone may be harmful in patients combatting obesity or heart failure. Insulin may exacerbate obesity and increase the risk of developing malignancy. This review thoroughly discusses the roles of these extra-glycemic effects and safety considerations in LTRs. Through weighing the risks and benefits, we conclude that alternatives to insulin should be strongly considered, when feasible, for personalized long-term management based on risk factors and co-morbidities.

Ipragliflozin attenuates non-alcoholic steatohepatitis development in an animal model

Non-alcoholic steatohepatitis (NASH) is a common chronic liver disease with no decisive treatment. The sodium glucose cotransporter 2 (SGLT2) inhibitor ipragliflozin was developed as a new oral hypoglycemic drug, which can improve NASH via an insulin-independent glucose-lowering effect by inhibiting glucose reabsorption in the renal proximal tubules. However, ipragliflozin appears to modulate steatosis or inflammation via different pathways. To elucidate the new mechanism of ipragliflozin for the treatment of NASH, we evaluated its effects in a NASH mouse model (STAM mice) with beta cell depletion, and compared the expression of microRNAs (miRNAs) in STAM mice treated with or without ipragliflozin (16.7 μg/day for 5 weeks). Ipragliflozin reduced aspartate transaminase and alanine aminotransferase levels, along with reduced hepatic steatosis, hepatocyte ballooning, lobular inflammation, and liver fibrosis. In addition, ipragliflozin upregulated mitochondrial transport-related and antioxidant defensive system-related genes in the liver. Among 2555 mouse miRNA probes, miR-19b-3p was commonly differentially expressed with ipragliflozin treatment for 5 weeks in both the liver and serum but in different directions, with a decrease in the liver and increase in the serum. Therefore, ipragliflozin can improve NASH development likely through the antioxidative stress pathway and by regulating miR-19b-3p.

Tocopheryl quinone improves non-alcoholic steatohepatitis (NASH) associated dysmetabolism of glucose and lipids by upregulating the expression of glucagon-like peptide 1 (GLP-1) via restoring the balance of intestinal flora in rats

CONTEXT

Glucagon-like peptide 1 (GLP-1) and α-tocopheryl quinone can promote the growth of intestinal flora and affect the pathogenesis of non-alcoholic steatohepatitis (NASH).

OBJECTIVE

This study determines the molecular mechanism of the effect of tocopheryl quinone in the treatment of high cholesterol and cholate diet (HFCC)-induced NASH.

MATERIALS AND METHODS

Thirty-two male Sprague Dawley (SD) rats grouped as lean control (LC), LC + tocopheryl quinone (1 mL of 3 × 10⁶ dpm tocopheryl quinone via i.p. injection), HFCC (5.1 kcal/g of fat diet), and HFCC + tocopheryl quinone. Profiles of intestinal flora were assessed by 16S ribosomal ribonucleic acid-based analysis. Levels and activity of GLP-1, interleukin 6 (IL-6) and tumour necrosis factor alpha (TNF-α) in intestinal tissues were detected by immunohistochemistry (IHC), Western blot and enzyme-linked immunosorbent assay (ELISA).

RESULTS

HFCC rats presented higher levels of cholesterol, low-density lipoprotein (LDL) and high-density lipoprotein (HDL), while tocopheryl quinone reversed the effects of HFCC. HFCC dysregulated malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), Vitamin E, 12-hydroxyeicosatetraenoic acid (12-HETE), 13-hydroxyoctadecadienoic acid (13-HODE) and nuclear factor kappa B (NF-κB), and the effects of HFCC were reversed by the treatment of tocopheryl quinone. Also, GLP-1 in the HFCC group was down-regulated while the IL-6 and TNF-α activity and endotoxins were all up-regulated. HFCC significantly decreased the number and diversity of bacteria, whereas tocopheryl quinone substantially restored the balance of intestinal flora and promoted the growth of both Bacteroides and Lactobacilli in vitro.

DISCUSSION AND CONCLUSIONS

α-Tocopheryl quinone relieves HFCC-induced NASH via regulating oxidative stress, GLP-1 expression, intestinal flora imbalance, and the metabolism of glucose and lipids.

The impact of sodium glucose co-transporter 2 inhibitors on non-alcoholic fatty liver disease

Affecting one fourth of the global population, non-alcoholic fatty liver disease (NAFLD) is the commonest chronic liver disorder. It encompasses the simple liver fat accumulation to more progressive steatosis, inflammation, and fibrosis characterized as non-alcoholic steatohepatitis (NASH) and in some cases cirrhosis and hepatocellular carcinoma. NAFLD regularly coexists with metabolic disorders, such as obesity and mostly type 2 diabetes mellitus (T2DM). A relatively new class of antidiabetic drugs, the sodium glucose co-transporter 2 (SGLT2) inhibitors exert their action by increasing the urinary glucose and calorie excretion leading to ameliorated plasma glucose levels and lower bodyweight. Recently, several animal studies and human clinical trial have emphasized the possible beneficial impact of SGLT2 inhibitors on NAFLD and its progression to NASH. In this present review, we summarize the current literature regarding the efficacy of the aforementioned category of drugs on anthropometric, laboratory, and histological features of patients with NAFLD. Conclusively, as SGLT2 inhibitors seem to be an appealing therapeutic opportunity for NAFLD management, we identify the open issues and questions to be addressed in order to clarify the impact in choosing antidiabetic medication to treat NAFLD patients associated with T2DM.

Safety, tolerability, and pharmacokinetics of the novel pan-phosphodiesterase inhibitor ZSP1601 in healthy subjects: a double-blinded, placebo-controlled first-in-human single-dose and multiple-dose escalation and food effect study

Background: The pharmacokinetics (PK), safety, and tolerability profiles of ZSP1601, a first-in-class pan-phosphodiesterase (PDE) inhibitor, were evaluated in healthy Chinese volunteers.Research design and methods: This Phase 1a study consisted of a double-blinded, randomized, placebo-controlled single ascending dose (SAD) (25 to 350 mg), multiple ascending doses (MAD) (50 or 100 mg QD), and a two-period crossover food effect study (100 mg).Results: ZSP1601 was quickly absorbed, with maximum plasma concentrations (C_max) reached at 1.25 to 2.50 h (median T_max). The exposures exhibited dose-proportional increases, while the mean half-life (t1/2) ranged from 6.34-8.64 h. Steady-state was reached within seven days in the MAD study. The mean steady trough concentrations were 423 and 588 ng/mL, respectively. ZSP1601 accumulation was low, with ratios ≤ 1.5. The bioavailability of ZSP1601 was equivalent under fasted and fed states. All adverse events (AEs) were assessed as mild or moderate, with headaches as the most common. The highest single doses (275 and 350 mg) yielded more AEs, yet the rates were similar with the placebo cohorts in the MAD study.Conclusions: The safety and PK profiles of ZSP1601 support further efficacy evaluation in nonalcoholic steatohepatitis patients.Trial registration: The trial is registered at ClinicalTrials.gov (CT.gov identifier: NCT03392779).

Unexpected Pleiotropic Effects of SGLT2 Inhibitors: Pearls and Pitfalls of This Novel Antidiabetic Class

Sodium-glucose co-transporter 2 (SGLT2) inhibitors facilitate urine glucose excretion by reducing glucose reabsorption, leading to ameliorate glycemic control. While the main characteristics of type 2 diabetes mellitus are insufficient insulin secretion and insulin resistance, SGLT2 inhibitors have some favorable effects on pancreatic β-cell function and insulin sensitivity. SGLT2 inhibitors ameliorate fatty liver and reduce visceral fat mass. Furthermore, it has been noted that SGLT2 inhibitors have cardio-protective and renal protective effects in addition to their glucose-lowering effect. In addition, several kinds of SGLT2 inhibitors are used in patients with type 1 diabetes mellitus as an adjuvant therapy to insulin. Taken together, SGLT2 inhibitors have amazing multifaceted effects that are far beyond prediction like some emerging magical medicine. Thereby, SGLT2 inhibitors are very promising as relatively new anti-diabetic drugs and are being paid attention in various aspects. It is noted, however, that SGLT2 inhibitors have several side effects such as urinary tract infection or genital infection. In addition, we should bear in mind the possibility of diabetic ketoacidosis, especially when we use SGLT2 inhibitors in patients with poor insulin secretory capacity.

Constitutive Androstane Receptor-Mediated Inhibition of Metformin on Phase II Metabolic Enzyme SULT2A1

BACKGROUND

Metformin, as a first-line treatment for diabetes, interacts with many protein kinases and transcription factors which affect the expression of downstream target genes governing drug metabolism. Sulfotransferase, SULT2A1, one phase II metabolic enzyme, sulfonates both xenobiotic and endobiotic compounds to accelerate drug excretion. Herein, we designed experiments to investigate the effects and mechanisms of metformin on SULT2A1 expression in vitro.

METHODS

The hepatocellular carcinoma cell line, HepaRG, was cultured with different concentrations of metformin. The cell viability was measured using CCK8 kit. HepaRG was used to evaluate the protein expression of pregnane X receptor (PXR), the constitutive androstane receptor (CAR), SULT2A1, AMP-activated protein kinase (AMPK), and phosphorylation of AMPK (p-AMPK), respectively, at different concentrations of metformin with or without rifampin (human PXR activator) and CITCO (human CAR activator). The coregulators with CAR on SULT2A1 promoter response elements have also been characterized.

RESULTS

We showed that metformin did not affect the basic expression of SULT2A1 but could suppress the expression of SULT2A1 induced by the activator of human CAR. Investigations revealed that metformin which could block CAR nuclear translocation further suppress SULT2A1. In addition, we found that the prevented CAR transfer into the nucleus by metformin was partially an AMPK-dependent event.

CONCLUSION

The present study indicated that the activation of AMPK-CAR pathway mediated the suppression of SULT2A1 by metformin. Metformin may affect the metabolism and clearance of drugs which are SULT2A1 substrates. The results that emerged from this work provide substantial insights into an appropriate medication in the treatment of diabetes patients.

A Review of the Epidemiology, Pathophysiology, and Efficacy of Anti-diabetic Drugs Used in the Treatment of Nonalcoholic Fatty Liver Disease

In recent years, epidemiological studies have consistently demonstrated that the coexistence of nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM) is strongly associated with increased mortality and morbidity related to hepatic- and extrahepatic causes. Indeed, compared with the general population, patients with T2DM are more likely to be diagnosed with more severe forms of NAFLD (i.e., nonalcoholic steatohepatitis (NASH) with liver fibrosis). There is an ongoing debate whether NALFD is a consequence of diabetes or whether NAFLD is simply a component and manifestation of the metabolic syndrome, since liver fat (steatosis) and even more advanced stages of liver fibrosis can occur in the absence of diabetes. Nevertheless, insulin resistance is a key component of the mechanism of NAFLD development; furthermore, therapies that lower blood glucose concentrations also appear to be effective in the treatment of NAFLD. Here, we will discuss the pathophysiological and epidemiological associations between NAFLD and T2DM. We will also review currently available anti-diabetic agents with their regard to their efficacy of NAFLD/NASH treatment.

Newer second-line glucose-lowering drugs versus thiazolidinediones on cirrhosis risk among older US adult patients with type 2 diabetes

AIMS

Type 2 diabetes (T2D) accelerates progression of chronic liver disease to cirrhosis, yet the effects of most glucose-lowering drugs (GLDs) on cirrhosis risk in T2D are unknown. To address this gap, we compared cirrhosis risk following initiation of newer second-line GLDs vs. thiazolidinediones (TZDs), which improve histology in non-alcoholic fatty liver disease.

MATERIALS AND METHODS

Using the US Medicare Fee-for-Service database (2007-2015) and an active comparator, new-user design, we estimated crude incidence rates (IRs) and propensity-score adjusted hazard ratios (aHR) for incident cirrhosis, comparing newer GLDs (dipeptidyl peptidase-4 inhibitors (DPP4i), glucagon-like peptide-1 receptor agonists (GLP1RA), and sodium-glucose co-transporter 2 inhibitors (SGLT2i)) vs. TZDs.

RESULTS

Among 239,549 total initiators, we observed 318, 151, and < 30 cirrhosis events when comparing DPP4i vs. TZD, GLP1RA vs. TZD, and SGLT2i vs. TZD, respectively. IRs ranged from 1.7 [95% CI, 0.8-3.6] to 3.6 [2.5-5.2] events per 1000 person-years. Point aHR estimates for cirrhosis were elevated among newer GLD initiators vs. TZD (DPP4i: 1.15 [0.89-1.50]; GLP1RA: 1.34 [0.82-2.20]; SGLT2i: 1.16, [0.44-3.08]), although estimates were imprecise due to short durations of drug exposure.

CONCLUSIONS

We observed mildly elevated cirrhosis risk with newer GLDs vs. TZD; however, uncertainty remains due to imprecise and statistically non-significant effect estimates.

Latin American Association for the study of the liver (ALEH) practice guidance for the diagnosis and treatment of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) currently represents an epidemic worldwide. NAFLD is the most frequently diagnosed chronic liver disease, affecting 20-30% of the general population. Furthermore, its prevalence is predicted to increase exponentially in the next decades, concomitantly with the global epidemic of obesity, type 2 diabetes mellitus (T2DM), and sedentary lifestyle. NAFLD is a clinical syndrome that encompasses a wide spectrum of associated diseases and hepatic complications such as hepatocellular carcinoma (HCC). Moreover, this disease is believed to become the main indication for liver transplantation in the near future. Since NAFLD management represents a growing challenge for primary care physicians, the Asociación Latinoamericana para el Estudio del Hígado (ALEH) has decided to organize this Practice Guidance for the Diagnosis and Treatment of Non-Alcoholic Fatty Liver Disease, written by Latin-American specialists in different clinical areas, and destined to general practitioners, internal medicine specialists, endocrinologists, diabetologists, gastroenterologists, and hepatologists. The main purpose of this document is to improve patient care and awareness of NAFLD. The information provided in this guidance may also be useful in assisting stakeholders in the decision-making process related to NAFLD. Since new evidence is constantly emerging on different aspects of the disease, updates to this guideline will be required in future.

Metabolic liver disease in diabetes - From mechanisms to clinical trials

Non-alcoholic fatty liver disease (NAFLD) comprises fatty liver (steatosis), non-alcoholic steatohepatitis (NASH) and fibrosis/cirrhosis and may lead to end-stage liver failure or hepatocellular carcinoma. NAFLD is tightly associated with the most frequent metabolic disorders, such as obesity, metabolic syndrome, and type 2 diabetes mellitus (T2DM). Both multisystem diseases share several common mechanisms. Alterations of tissue communications include excessive lipid and later cytokine release by dysfunctional adipose tissue, intestinal dysbiosis and ectopic fat deposition in skeletal muscle. On the hepatocellular level, this leads to insulin resistance due to abnormal lipid handling and mitochondrial function. Over time, cellular oxidative stress and activation of inflammatory pathways, again supported by multiorgan crosstalk, determine NAFLD progression. Recent studies show that particularly the severe insulin resistant diabetes (SIRD) subgroup (cluster) associates with NAFLD and its accelerated progression and increases the risk of diabetes-related cardiovascular and kidney diseases, underpinning the critical role of insulin resistance. Consequently, lifestyle modification and certain drug classes used to treat T2DM have demonstrated effectiveness for treating NAFLD, but also some novel therapeutic concepts may be beneficial for both NAFLD and T2DM. This review addresses the bidirectional relationship between mechanisms underlying T2DM and NAFLD, the relevance of novel biomarkers for improving the diagnostic modalities and the identification of subgroups at specific risk of disease progression. Also, the role of metabolism-related drugs in NAFLD is discussed in light of the recent clinical trials. Finally, this review highlights some challenges to be addressed by future studies on NAFLD in the context of T2DM.

Nonalcoholic Fatty Liver Disease (NAFLD) and Hepatic Cytochrome P450 (CYP) Enzymes

Nonalcoholic fatty liver disease (NAFLD) is characterized by excessive fat in the liver. An international consensus panel has recently proposed to rename the disease to metabolic dysfunction associated with fatty liver disease (MAFLD). The disease can range from simple steatosis (fat accumulation) to nonalcoholic steatohepatitis (NASH) which represents a severe form of NAFLD and is accompanied by inflammation, fibrosis, and hepatocyte damage in addition to significant steatosis. This review collates current knowledge of changes in human hepatic cytochrome P450 enzymes in NAFLD. While the expression of these enzymes is well studied in healthy volunteers, our understanding of the alterations of these proteins in NAFLD is limited. Much of the existing knowledge on the subject is derived from preclinical studies, and clinical translation of these findings is poor. Wherever available, the effect of NAFLD on these proteins in humans is debatable and currently lacks a consensus among different reports. Protein expression is an important in vitro physiological parameter controlling the pharmacokinetics of drugs and the last decade has seen a rise in the accurate estimation of these proteins for use with physiologically based pharmacokinetic (PBPK) modeling to predict drug pharmacokinetics in special populations. The application of label-free, mass spectrometry-based quantitative proteomics as a promising tool to study NAFLD-associated changes has also been discussed.

Ipragliflozin-induced improvement of liver steatosis in obese mice may involve sirtuin signaling

BACKGROUND

Sodium glucose cotransporter 2 (SGLT2) inhibitors are newly developed oral antidiabetic drugs. SGLT2 is primarily expressed in the kidneys and reabsorbs approximately 90% of the glucose filtered by the renal glomeruli. SGLT2 inhibitors lower glucose levels independently of insulin action by facilitating urinary glucose excretion. The SGLT2 inhibitor ipragliflozin has reportedly improved liver steatosis in animal models and clinical studies. However, the mechanisms by which SGLT2 inhibitors improve liver steatosis are not fully understood.

AIM

To investigate the ameliorative effects of ipragliflozin on liver steatosis and the mechanisms of these effects in obese mice.

METHODS

We analyzed 8-wk-old male obese (ob/ob) mice that were randomly divided into a group receiving a normal chow diet and a group receiving a normal chow diet supplemented with ipragliflozin (3 mg/kg or 10 mg/kg) for 4 wk. We also analyzed their lean sex-matched littermates receiving a normal chow diet as another control group. Body weight and liver weight were evaluated, and liver histology, immunoblotting, and reverse transcription-polymerase chain reaction analyses were performed.

RESULTS

Hepatic lipid accumulation was significantly ameliorated in ob/ob mice treated with 10 mg/kg ipragliflozin compared to untreated ob/ob mice irrespective of body weight changes. Ipragliflozin had no appreciable effects on hepatic oxidative stress-related gene expression levels or macrophage infiltration, but significantly reduced hepatic interleukin-1β (IL-1β) mRNA expression levels. Ipragliflozin increased both the mRNA and protein expression levels of sirtuin 1 (SIRT1) in the liver. The hepatic mRNA levels of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), peroxisome proliferator-activated receptor α (PPARα), and fibroblast growth factor-21 (FGF21) were also significantly higher in ipragliflozin-treated ob/ob mice than in untreated ob/ob mice.

CONCLUSION

Our study suggests that the liver steatosis-ameliorating effects of ipragliflozin in ob/ob mice may be mediated partly by hepatic SIRT1 signaling, possibly through the PGC-1α/PPARα-FGF21 pathway.

Determining whether the effect of liraglutide on non-alcoholic fatty liver disease depends on reductions in the body mass index

Background and Aim

Non‐alcoholic fatty liver disease (NAFLD) initially presents as steatosis, which can progress to non‐alcoholic steatohepatitis (NASH), and often presents clinically alongside metabolic syndromes. Glucagon‐like peptide‐1 receptor agonists (GLP‐1 RAs) are regularly utilized to treat type 2 diabetes mellitus. The GLP‐1 RA—liraglutide—ameliorates liver enzymes, histological features, and liver fat content of patients with NASH. However, few studies have examined whether the effect of GLP‐1 RAs depends on changes in the patient's body mass index (BMI). Therefore, this retrospective study aimed to investigate whether the efficacy of liraglutide depended on the baseline BMI or a reduction in BMI.

Methods

Fifty‐five Japanese patients with type 2 diabetes mellitus and NAFLD who received liraglutide treatment for 24 weeks were assessed. The association between BMI and liver function or fibrosis was evaluated based on the aspartate aminotransferase, alanine aminotransferase, and fibrosis‐4 indices.

Results

We found that 24 weeks of liraglutide treatment improved liver function and fibrosis in patients with type 2 diabetes mellitus and NAFLD, regardless of BMI changes or obesity status.

Conclusions

Our findings provide important insight into the impact of BMI on liver function and fibrosis in patients with type 2 diabetes mellitus and NAFLD who are treated with liraglutide.

Thyroid-stimulating hormone is an independent risk factor of non-alcoholic fatty liver disease

BACKGROUND AND AIM

Hypothyroidism might play a crucial role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). The association of subclinical hypothyroidism with NAFLD has been inconsistent. The relationship of NAFLD with thyroid function parameters and subclinical hypothyroidism was determined.

METHODS

This cross-sectional study included 70 patients with subclinical hypothyroidism and 70 controls with euthyroidism matched according to gender, age, and body mass index (BMI). NAFLD was diagnosed via abdominal ultrasonography. The association between NAFLD and subclinical hypothyroidism was analyzed.

RESULTS

The prevalence of NAFLD was significantly higher in patients with subclinical hypothyroidism than in those with euthyroidism. Multivariate analysis showed that subclinical hypothyroidism was an independent risk factor of NAFLD adjusted by metabolic-related factors, such as BMI, triglyceride, high-density lipoprotein-cholesterol, hypertension, and diabetes. Thyroid-stimulating hormone (TSH) was an independent risk factor of NAFLD adjusted by the same metabolic-related factors, but free thyroxine (FT4) was not a risk factor. The FIB-4 index, a noninvasive marker of liver fibrosis was significantly higher in patients with subclinical hypothyroidism than in those with euthyroidism. Compared with patients with euthyroidism, the proportion of the FIB-4 index ≥2.67 was significantly higher, and the proportion of the FIB-4 index <1.30 was lower in patients with subclinical hypothyroidism.

CONCLUSIONS

TSH elevation even within the euthyroid range is an independent risk factor of NAFLD and may influence the progression of liver fibrosis, even with a normal FT4 level.

Comparison of the effects of three kinds of glucose-lowering drugs on non-alcoholic fatty liver disease in patients with type 2 diabetes: A randomized, open-label, three-arm, active control study

Aims/Introduction

Non‐alcoholic fatty liver disease (NAFLD) is often observed in individuals with type 2 diabetes mellitus, and it is known that the presence of type 2 diabetes mellitus leads to the aggravation of NAFLD. The aim of this study was to compare the possible effects of three kinds of oral hypoglycemic agents on NAFLD in individuals with type 2 diabetes mellitus.

Materials and Methods

We carried out a prospective clinical trial (a randomized and open‐label study) in patients with type 2 diabetes mellitus and NAFLD. A total of 98 patients were randomly allocated either to the dapagliflozin (n = 32), pioglitazone (n = 33) or glimepiride (n = 33) group, and the patients took these drugs for 28 weeks. The primary end‐point was the change of the liver‐to‐spleen ratio on abdominal computed tomography.

Results

There was no difference in baseline clinical characteristics among the three groups. Dapagliflozin, pioglitazone and glimepiride ameliorated hyperglycemia similarly. Bodyweight and visceral fat area were significantly decreased only in the dapagliflozin group. Serum adiponectin levels were markedly increased in the pioglitazone group compared with the other two groups. Dapagliflozin and pioglitazone, but not glimepiride, significantly increased the liver‐to‐spleen ratio, and the effects of dapagliflozin and pioglitazone on the liver‐to‐spleen ratio were comparable.

Conclusions

The present study showed that the decrease of visceral fat area and the increase of adiponectin level contributed to the improvement of NAFLD in patients with type 2 diabetes mellitus. Furthermore, dapagliflozin and pioglitazone exerted equivalent beneficial effects on NAFLD in patients with type 2 diabetes mellitus, although it seemed that these two drugs had different mechanisms of action.

Current and new pharmacotherapy options for non-alcoholic steatohepatitis

INTRODUCTION

There is an unmet medical need for an effective anti-fibrotic treatment for NASH with advanced fibrosis.

AREAS COVERED

The authors review the current and novel agents for the treatment of NASH with fibrosis. They also consider the potential future strategies of combination therapies.

EXPERT OPINION

Farnesoid X receptor (FXR) agonist (obeticholic acid [OCA]) significantly ameliorated hepatic fibrosis in NASH stage 2/3 fibrosis in an interim analysis of phase 3 trial. Because OCA has several drawbacks such as itching and elevated low-density lipoprotein-cholesterol (LDL-C), non-bile acid FXR agonists are now under development. Selonsertib (apoptosis signaling kinase 1 inhibitor), emricasan (an irreversible pan-caspase inhibitor), and simtsuzumab (a monoclonal antibody against lysyl oxidase-like 2) were discontinued because of no efficacy over placebo. Peroxisome proliferator-activator receptor α/δ agonists, C-C motif chemokine receptor-2/5 antagonists, and thyroid β receptor agonist are ongoing in phase 3 trials. A variety of agents including fibroblast growth factor (FGF)-21 and FGF-19 agonists, as well as acetyl-CoA carboxylase inhibitors, are also expected. Among antidiabetic agents, semaglutide, a novel GLP-1 RA, is ongoing for NASH stage 1-3 fibrosis in a phase 2 trial. Furthermore, the combination of GLP-RA/glucagon receptor agonist and GLP-RA/gastrointestinal peptide agonist are promising future options.

Antidiabetic Therapy in the Treatment of Nonalcoholic Steatohepatitis

Liver-related diseases are the third-leading causes (9.3%) of mortality in type 2 diabetes (T2D) in Japan. T2D is closely associated with nonalcoholic fatty liver disease (NAFLD), which is the most prevalent chronic liver disease worldwide. Nonalcoholic steatohepatitis (NASH), a severe form of NAFLD, can lead to hepatocellular carcinoma (HCC) and hepatic failure. No pharmacotherapies are established for NASH patients with T2D. Though vitamin E is established as a first-line agent for NASH without T2D, its efficacy for NASH with T2D recently failed to be proven. The effects of pioglitazone on NASH histology with T2D have extensively been established, but several concerns exist, such as body weight gain, fluid retention, cancer incidence, and bone fracture. Glucagon-like peptide 1 (GLP-1) receptor agonists and sodium-glucose cotransporter 2 (SGLT2) inhibitors are expected to ameliorate NASH and NAFLD (LEAN study, LEAD trial, and E-LIFT study). Among a variety of SGLT2 inhibitors, dapagliflozin has already entered the phase 3 trial (DEAN study). A key clinical need is to determine the kinds of antidiabetic drugs that are the most appropriate for the treatment of NASH to prevent the progression of hepatic fibrosis, resulting in HCC or liver-related mortality without increasing the risk of cardiovascular or renal events. Combination therapies, such as glucagon receptor agonist/GLP-1 or gastrointestinal peptide/GLP-1, are under development. This review focused on antidiabetic agents and future perspectives on the view of the treatment of NAFLD with T2D.

Fructo-oligosaccharides ameliorate steatohepatitis, visceral adiposity, and associated chronic inflammation via increased production of short-chain fatty acids in a mouse model of non-alcoholic steatohepatitis

Background

Non-alcoholic fatty liver disease (NAFLD) is a hepatic manifestation of metabolic syndrome. Within the spectrum of NAFLD, non-alcoholic steatohepatitis (NASH) in combination with hepatic inflammation and fibrosis can lead to liver cirrhosis and hepatocellular carcinoma. Dysbiosis was reported to contribute to NASH pathogenesis. This study aimed to determine the effects of fructo-oligosaccharides (FOS) on steatohepatitis and visceral adiposity in an obese mouse model of NASH.

Methods

Twelve newborn C57BL/6 J male mice were subcutaneously injected with monosodium glutamate (MSG) to induce obesity on a conventional diet. Six mice were also administered 5% FOS via drinking water from 10 weeks of age. At 18 weeks, histological characteristics of the liver and epididymal fat were compared between the groups. Hepatic mRNA expression of lipid metabolism enzymes and SCFA in feces and sera were measured.

Results

Hepatic steatosis, inflammatory cell infiltration, and hepatocyte ballooning in the liver and increased hepatic mRNA expression of fatty acid synthase and glycerol-3-phosphate acyltransferase were observed in the MSG-treated mice. FOS treatment improved the liver pathology and blunted the increases in the mRNA expression levels of lipid metabolism enzymes. In addition, FOS inhibited adipocyte enlargement and formation of crown-like structures and reduced the M1 macrophage frequency in the epididymal fat of the MSG mice (39.4% ± 3.0% vs. 22.8% ± 0.7%; P = 0.001). FOS increased not only the fecal concentrations of n-butyric acid (0.04 ± 0.01 vs. 0.38 ± 0.14 mg/g, P = 0.02), propionic acid (0.09 ± 0.03 vs. 0.42 ± 0.16 mg/g, P = 0.02), and acetic acid (0.65 ± 0.16 vs. 1.48 ± 0.29 mg/g, P = 0.03) but also the serum concentration of propionic acid (3.9 ± 0.5 vs. 8.2 ± 0.5 μmol/L, P = 0.001).

Conclusions

FOS ameliorates steatohepatitis, visceral adiposity, and chronic inflammation by increasing SCFA production.

The Relationship Between Prostate Cancer and Metformin Consumption: A Systematic Review and Meta-analysis Study

INTRODUCTION

Prostate cancer is the most common malignant cancer in men worldwide and after lung cancer, it is the second leading cause of cancer mortality in men. The purpose of this study was to investigate the relationship between prostate cancer and metformin consumption in men.

METHODS

The current study is a systematic and meta-analysis review based on the PRISMA statement. To access the studies of domestic and foreign databases, Iran Medex, SID, Magiran, Iran Doc, Medlib, ProQuest, Science Direct, PubMed, Scopus, Web of Science and the Google Scholar search engine were searched during the 2009- 2018 period for related keywords. In order to evaluate the heterogeneity of the studies, Q test and I2 indicator were used. The data were analyzed using the STATA 15.1 software.

RESULTS

In 11 studies with a sample size of 877058, the odds ratio of metformin consumption for reducing prostate cancer was estimated at 0.89 (95%CI: 0.67-1.17). Meta-regression also showed there was no significant relationship between the odds ratio and the publication year of the study. However, there was a significant relationship between the odds ratio and the number of research samples.

CONCLUSION

Using metformin in men reduces the risk of prostate cancer but it is not statistically significant.

Abnormal CD44 activation of hepatocytes with nonalcoholic fatty accumulation in rat hepatocarcinogenesis

BACKGROUND

Prevalence of nonalcoholic fatty liver disease (NAFLD) is rapidly increasing, and NAFLD has become one of the most common chronic liver diseases worldwide. With abnormal CD44 activation, the severe form of NAFLD can progress to liver cirrhosis and hepatocellular carcinoma (HCC). Thus, the molecular mechanism of CD44 in NAFLD needs to be identified.

AIM

To investigate the relationship between CD44 activation and malignant transformation of rat hepatocytes under nonalcoholic lipid accumulation.

METHODS

Sprague-Dawley rats were fed a high-fat (HF) for 12 wk to entice NAFLD and then with HF plus 2-fluorenylacetamide (0.05%) to induce HCC. Rats were sacrificed every 2 wk, and subsequently divided into the groups based on liver pathological examination (hematoxylin and eosin staining): NAFLD, denaturation, precancerosis, HCC, and control. Liver CD44 mRNA was detected by OneArray. Liver fat as assessed by Oil red O staining or CD44 by immunohistochemical assay was compared with their integral optic density. Serum CD44, alanine aminotransferase, aspartate aminotransferase, triglyceride, total cholesterol, and AFP levels were quantitatively tested.

RESULTS

Elevated CD44 was first reported in hepatocarcinogenesis, with increasing expression from NAFLD to HCC at the protein or mRNA level. The CD44 integral optic density values were significantly different between the control group and the NAFLD (t = 25.433, P < 0.001), denaturation (t = 48.822, P < 0.001), precancerosis (t = 27.751, P < 0.001), and HCC (t = 16.239, P < 0.001) groups, respectively. Hepatic CD44 can be secreted into the blood, and serum CD44 levels in HCC or precancerous rats were significantly higher (P < 0.001) than those in any of the other rats. Positive correlations were found between liver CD44 and CD44 mRNA (rs = 0.373, P = 0.043) and serum CD44 (rs = 0.541, P = 0.002) and between liver CD44 mRNA and serum CD44 (rs = 0.507, P = 0.004). Moreover, significant correlations were found between liver CD44 and liver AFP (rs = 0.572, P = 0.001), between serum CD44 and serum AFP (rs = 0.608, P < 0.001), and between CD44 mRNA and AFP mRNA (rs = 0.370, P = 0.044).

CONCLUSION

The data suggested that increasing CD44 expression is associated with the malignant transformation of hepatocytes in NAFLD.

Effect of Saxagliptin, a Dipeptidyl Peptidase 4 Inhibitor, on Non-Alcoholic Fatty Liver Disease

BACKGROUND AND AIM

Non-alcoholic fatty liver disease (NAFLD) represents a broad spectrum of chronic liver disease characterized by aberrant accumulation of triglycerides (TG) in hepatocytes without excessive alcohol consumption. Hepatic lipotoxicity derived from overaccumulation of free fatty acids is considered as one of the typical hallmarks of NAFLD. Insulin resistance (IR) and chronic inflammation are widely recognized as the key etiological factors associated with NAFLD. Dipeptidyl peptidase 4 inhibitor (DPP4i) is a novel pharmacological agent extensively applied in the treatment of Type 2 Diabetes Mellitus (T2DM) for decades which also have a liver protective effect.

METHODS

In order to invest the therapeutic efficiency and underlying mechanism of DPP4i saxagliptin, we used high-fat diet (HFD) and streptozotocin-induced NAFLD treated with saxagliptin. Biochemical, histomorphological, genetic and protein expression of related pathways were investigated.

RESULTS

Fasting blood glucose (FBG), TG, total cholesterol (TC), and low-density lipoprotein cholesterin significantly increased in NAFLD group, which also exhibited severe steatosis. Other remarkable findings were hyperinsulinemia, increased DPP4, PTP-1B and TNF-α level and decreased GLP-1, ACOX-1, CPT-1A expression, concomitant with liver DPP4 expression enhancement and serum DPP4 elevation. These undesirable consequences were alleviated by saxagliptin to a certain degree.

CONCLUSION

DPP4i saxagliptin improves NAFLD by ameliorating IR, inflammation, downregulation of hepatic DPP4 and sDPP4, as well as subsequent steatosis. The elevation of hepatic DPP4 and sDPP4 and succedent post-treatment decrease suggested that DPP4 may involve in the development of NAFLD. The anti-lipotoxic effect of DPP4i may involve the activation of CPT1A and ACOX1 related β-oxidation signaling pathway suppression of TNF-α mediated inflammatory and PTP-1B. The results covered in this article showed that saxagliptin affects many aspects of the pathological characteristics of NAFLD, suggesting that DPP4i saxagliptin may offer a novel therapeutic option for NAFLD.

Liver Transplantation for Nonalcoholic Steatohepatitis: Pathophysiology of Recurrence and Clinical Challenges

Nonalcoholic steatohepatitis is the fastest-growing indication for the liver transplant and a leading cause of hepatocellular carcinoma among patients listed for liver transplantation in the USA. Post-transplant nonalcoholic hepatic steatosis and steatohepatitis are frequent complications of liver transplantation. Nonalcoholic steatohepatitis poses a significant challenge in both pre- and post-transplant period due to its association with metabolic syndrome, coronary artery disease, chronic kidney disease, and obstructive sleep apnea. While optimal therapy is not yet available in the post-liver transplant setting, lifestyle interventions continue to remain as the mainstay of therapy for post-transplant nonalcoholic steatohepatitis. Early recognition with protocol biopsies and noninvasive modalities, along with modification of known risk factors, are the most effective methods to curtail the progression of nonalcoholic steatohepatitis in the absence of FDA-approved pharmacologic therapy.

Phase 3 drug pipelines in the treatment of non-alcoholic steatohepatitis

Non-alcoholic steatohepatitis (NASH), which is a more severe form of non-alcoholic fatty liver disease, can at least partly lead to cirrhosis, hepatocellular carcinoma, and hepatic failure. Liver transplantation is the only option for NASH cirrhosis at this time. By 2020, NASH is projected to overtake hepatitis C as the leading cause of liver transplants in the USA. There are still no approved drugs for treating NASH. Although there are approximately 196 agents of investigational NASH therapies in various stages of development, we here mainly review phase 3 drug candidates in the pipeline for NASH. The NASH space across the seven major markets of the USA, France, Germany, Italy, Spain, the UK, and Japan, is set to rise from $618 million in 2016 to approximately $25.3 billion by 2026. However, the fact that the race to develop an effective drug against NASH has reached the home stretch, with five drug candidates (obeticholic acid, elafibranor, selonsertib, cenicriviroc, and resmetirom) in phase 3 stage of the trial, is welcome news for patients. The very earliest a NASH drug could hit the market is 2021, assuming all goes well as planned.

Combined effect of a farnesoid X receptor agonist and dipeptidyl peptidase-4 inhibitor on hepatic fibrosis

AIM

Non-alcoholic steatohepatitis (NASH) has a broad clinicopathological spectrum (inflammation to severe fibrosis). The farnesoid X receptor agonist obeticholic acid (OCA) ameliorates the histological features of NASH; satisfactory antifibrotic effects have not yet been reported. Here, we investigated the combined effects of OCA + a dipeptidyl peptidase-4 inhibitor (sitagliptin) on hepatic fibrogenesis in a rat model of NASH.

METHODS

Fifty Fischer 344 rats were fed a choline-deficient L-amino-acid-defined (CDAA) diet for 12 weeks. The in vitro and in vivo effects of OCA + sitagliptin were assessed along with hepatic fibrogenesis, lipopolysaccharide-Toll-like receptor 4 (TLR4) regulatory cascade and intestinal barrier function. Direct inhibitory effects of OCA + sitagliptin on activated hepatic stellate cells (Ac-HSCs) were assessed in vitro.

RESULTS

Treatment with OCA + sitagliptin potentially inhibited hepatic fibrogenesis along with Ac-HSC proliferation and hepatic transforming growth factor (TGF)-β1, α1(I)-procollagen, and tissue inhibitor of metalloproteinase-1 (TIMP-1) mRNA expression and hydroxyproline levels. Obeticholic acid inhibited hepatic TLR4 expression and increased hepatic matrix metalloproteinase-2 expression. Obeticholic acid decreased intestinal permeability by ameliorating CDAA diet-induced zonula occludens-1 disruption, whereas sitagliptin directly inhibited Ac-HSC proliferation. The in vitro suppressive effects of OCA + sitagliptin on TGF-β1 and α1(I)-procollagen mRNA expression and p38 phosphorylation in Ac-HSCs were almost consistent. Sitagliptin directly inhibited the regulation of Ac-HSC.

CONCLUSIONS

Treatment with OCA + sitagliptin synergistically affected hepatic fibrogenesis by counteracting endotoxemia induced by intestinal barrier dysfunction and suppressing Ac-HSC proliferation. Thus, OCA + sitagliptin could be a promising therapeutic strategy for NASH.

Concurrent nonalcoholic fatty liver disease and type 2 diabetes: diagnostic and therapeutic considerations

Introduction: The relationship between nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM) is complex and bidirectional. NAFLD increases the risk of incident diabetes and is very prevalent in T2DM patients and T2DM is an aggravating factor for NAFLD. Timely T2DM diagnosis and treatment in subjects with NAFLD and diagnosis, staging and treatment of NAFLD in those with T2DM are critical issues. Areas covered: PubMed/MEDLINE was searched for articles related to concomitant occurrence of NAFLD and T2DM between January 2013 and May 2019. Areas covered included epidemiological, diagnostic and therapeutic aspects. Expert opinion: there is a need for increased awareness on NAFLD adding liver disease as an end-organ complication of T2DM. Emphasis on use of simple non-invasive tools to triage patients with potentially severe liver disease should be made. Management of patients with NAFLD and T2DM relies on lifestyle optimization to achieve significant weight loss. Currently, there is no drug approved for treatment of NAFLD in patients with T2DM although Vitamin E and pioglitazone might be used in selected patients. Approved diabetic medications hold promise for NAFLD treatment and several liver-specific drugs are in evaluation clinical trials. A combination approach will likely represent the future of NAFLD therapeutics.

Role and effective therapeutic target of gut microbiota in NAFLD/NASH

Non-alcoholic fatty liver disease (NAFLD), the most prevalent chronic liver disease in the world, is affected by numerous extrinsic and intrinsic factors, including lifestyle, environment, diet, genetic susceptibility, metabolic syndrome and gut microbiota. Accumulating evidence has proven that gut dysbiosis is significantly associated with the development and progression of NAFLD, and several highly variable species in gut microbiota have been identified. The gut microbiota contributes to NAFLD by abnormal regulation of the liver-gut axis, gut microbial components and microbial metabolites, and affects the secretion of bile acids. Due to the key role of the gut microbiota in NAFLD, it has been regarded as a potential target for the pharmacological and clinical treatment of NAFLD. The present review provides a systematic summary of the characterization of gut microbiota and the significant association between the gut microbiota and NAFLD. The possible mechanisms of how the gut microbiota is involved in promoting the development and progression of NAFLD were also discussed. In addition, the potential therapeutic methods for NAFLD based on the gut microbiota were summarized.

A Comprehensive Study of High Cholesterol Diet-Induced Larval Zebrafish Model: A Short-Time In Vivo Screening Method for Non-Alcoholic Fatty Liver Disease Drugs

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease around the world. However, there is still no drug for NAFLD in the market, the study of potential therapeutic drugs on NAFLD is extraordinarily pressing and urgent. The rodent models for NAFLD drugs' study are always with a long time cost. Therefore, we aim to establish a short-time NAFLD drug screening model. A laboratory-made high cholesterol diet was used on larval zebrafish for 3 weeks to establish the NAFLD screen model. Lipid metabolism, oxidant stress, and pathology were studied to comprehensively demonstrate the whole spectrum of NAFLD on this model. Bezafibrate and pioglitazone were used to evaluate the model. Moreover, mechanism research was performed on this model.The NAFLD larval zebrafish model was established with the comprehensive process of NAFLD. Moreover, multiple index on lipid metabolism, oxidant stress, hepatic steatosis, and hepatic inflammation can be easily tested for drug screening. Furthermore, this model can be used to perform the mechanism research by testing mRNA expression. The NAFLD larval zebrafish model is a comprehensive short-time screening method for NAFLD drugs.

SGLT1 in pancreatic α cells regulates glucagon secretion in mice, possibly explaining the distinct effects of SGLT2 inhibitors on plasma glucagon levels

OBJECTIVES

It is controversial whether sodium glucose transporter (SGLT) 2 inhibitors increase glucagon secretion via direct inhibition of SGLT2 in pancreatic α cells. The role of SGLT1 in α cells is also unclear. We aimed to elucidate these points that are important not only for basic research but also for clinical insight.

METHODS

Plasma glucagon levels were assessed in the high-fat, high-sucrose diet (HFHSD) fed C57BL/6J mice treated with dapagliflozin or canagliflozin. RT-PCR, RNA sequence, and immunohistochemistry were conducted to test the expression of SGLT1 and SGLT2 in α cells. We also used αTC1 cells and mouse islets to investigate the molecular mechanism by which SGLT1 modulates glucagon secretion.

RESULTS

Dapagliflozin, but not canagliflozin, increased plasma glucagon levels in HFHSD fed mice. SGLT1 and glucose transporter 1 (GLUT1), but not SGLT2, were expressed in αTC1 cells, mouse islets and human islets. A glucose clamp study revealed that the plasma glucagon increase associated with dapagliflozin could be explained as a response to acute declines in blood glucose. Canagliflozin suppressed glucagon secretion by inhibiting SGLT1 in α cells; consequently, plasma glucagon did not increase with canagliflozin, even though blood glucose declined. SGLT1 effect on glucagon secretion depended on glucose transport, but not glucose metabolism. Islets from HFHSD and db/db mice displayed higher SGLT1 mRNA levels and lower GLUT1 mRNA levels than the islets from control mice. These expression levels were associated with higher glucagon secretion. Furthermore, SGLT1 inhibitor and siRNA against SGLT1 suppressed glucagon secretion in isolated islets.

CONCLUSIONS

These data suggested that a novel mechanism regulated glucagon secretion through SGLT1 in α cells. This finding possibly explained the distinct effects of dapagliflozin and canagliflozin on plasma glucagon levels in mice.

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.

Effect of luseogliflozin on hepatic fat content in type 2 diabetes patients with non-alcoholic fatty liver disease: A prospective, single-arm trial (LEAD trial)

AIMS

No pharmacological therapies are approved for non-alcoholic fatty liver disease (NAFLD). Luseogliflozin, a sodium glucose cotransporter 2 inhibitor, has been developed for the treatment of adults with type 2 diabetes (T2DM). The aim of this prospective, single-arm study is to evaluate the efficacy of luseogliflozin on hepatic fat content and glycated hemoglobin (HbA1c) in T2DM patients with NAFLD.

METHODS

Forty T2DM patients with NAFLD were treated with luseogliflozin 2.5 mg/day for 24 weeks. Primary end-points were changes in HbA1c and hepatic steatosis evaluated by magnetic resonance imaging-hepatic fat fraction from baseline. Secondary end-points were changes in metabolic and hepatic function-related parameters, including hepatic fibrosis markers (Fibrosis-4 index, NAFLD fibrosis score, type IV collagen 7S. and Wisteria floribunda agglutinin-positive Mac-2 binding protein).

RESULTS

Not only HbA1c and transaminase activities but also hepatic fat content were significantly decreased after 24 weeks of therapy with luseogliflozin. The reduction of hepatic fat content was significantly correlated with the reduction of alanine aminotransferase. Although hepatic fibrosis markers were unchanged, serum ferritin levels reduced and serum albumin significantly increased after the treatment.

CONCLUSION

Luseogliflozin can be a novel promising agent for the treatment of T2DM patients with NAFLD. Prospective randomized controlled trials are warranted to confirm this impact of luseogliflozin onT2DM with NAFLD.

Pharmacotherapy of type 2 diabetes in patients with chronic liver disease: focus on nonalcoholic fatty liver disease

INTRODUCTION

Pharmacotherapy used to treat type 2 diabetes mellitus (T2DM) is facing a paradigm shift in clinical practice with recent cardiovascular (CV) outcome trials having a substantial impact on drug prescription with treatment having a more tailored approach. In patients with T2DM, the issue of chronic liver disease is multifaceted. However, a clinical evidence is emerging on the beneficial effect of antidiabetic medications on nonalcoholic fatty liver disease (NAFLD).

AREAS COVERED

The authors provide a synopsis on the current and upcoming pharmacotherapy for NAFLD, including the challenges with their development, focusing on drugs for T2DM. Clinical data on the potential benefits and safety issues are assessed with the aim of proposing an individualized algorithm for patient management. Both MEDLINE and ClinicalTrials.Gov are used to derive the relevant information.

EXPERT OPINION

Considering the pivotal role of insulin resistance in NAFLD, insulin sensitizers should be the treatment of choice. Accordingly, pioglitazone is the only drug with a significant effect on liver fibrosis, the driver of disease progression and long-term outcome. Among new glucose-lowering drugs, glucagon-like-peptide 1 receptor agonists or sodium-glucose cotransporter type 2 inhibitors have shown positive effects in phase II studies and are qualifying as potential candidates for NAFLD treatment in diabetes.

A novel dual PPAR-γ agonist/sEH inhibitor treats diabetic complications in a rat model of type 2 diabetes

AIMS/HYPOTHESIS

The metabolic syndrome is a cluster of risk correlates that can progress to type 2 diabetes. The present study aims to evaluate a novel molecule with a dual action against the metabolic syndrome and type 2 diabetes.

METHODS

We developed and tested a novel dual modulator, RB394, which acts as a soluble epoxide hydrolase (sEH) inhibitor and a peroxisome proliferator-activated receptor-γ (PPAR-γ) agonist in rat models of the metabolic syndrome-the obese spontaneously hypertensive (SHROB) rat and the obese diabetic Zucker fatty/spontaneously hypertensive heart failure F1 hybrid (ZSF1) rat. In SHROB rats we studied the ability of RB394 to prevent metabolic syndrome phenotypes, while in ZSF1 obese diabetic rats we compared RB394 with the ACE inhibitor enalapril in the treatment of type 2 diabetes and associated comorbid conditions. RB394 (10 mg/kg daily) and enalapril (10 mg/kg daily) were administered orally for 8 weeks.

RESULTS

RB394 blunted the development of hypertension, insulin resistance, hyperlipidaemia and kidney injury in SHROB rats and reduced fasting blood glucose and HbA_1c, improved glucose tolerance, reduced blood pressure and improved lipid profiles in obese ZSF1 rats. A reduction in liver fibrosis and hepatosteatosis was evident in RB394-treated obese ZSF1 rats. Unlike RB394, enalapril did not demonstrate any positive effects in relation to diabetes, hyperlipidaemia or liver dysfunction in obese ZSF1 rats. RB394 ameliorated diabetic nephropathy by reducing renal interstitial fibrosis and renal tubular and glomerular injury in obese diabetic ZSF1 rats. Intriguingly, enalapril demonstrated a weaker action against diabetic nephropathy in obese ZSF1 rats.

CONCLUSIONS/INTERPRETATION

These findings demonstrate that a novel sHE inhibitor/PPAR-γ agonist molecule targets multiple risk factors of the metabolic syndrome and is a glucose-lowering agent with a strong ability to treat diabetic complications.

Metformin: An Old Drug with New Applications

Metformin is a biguanide drug that has been used to treat type 2 diabetes mellitus for more than 60 years. The United Kingdom Prospective Diabetic Study (UKPDS) has shown metformin to improve mortality rates in diabetes patients, and recent studies suggest metformin has additional effects in treating cancer, obesity, nonalcoholic fatty liver disease (NAFLD), polycystic ovary syndrome (PCOS), and metabolic syndrome. Metformin has also been shown to alleviate weight gain associated with antipsychotic medication. Metformin has recently been extensively studied and emerging evidence suggests metformin decreases hepatocyte triglyceride accumulation in NAFLD and prevents liver tumorigenesis. Interestingly, studies have also shown metformin reduces visceral fat, suppresses white-adipose-tissue (WAT) extracellular matrix remodeling, and inhibits obesity-induced inflammation. However, clinical evidence for using metformin to treat NAFLD, cancer, metabolic syndrome, or to prevent hepatocellular carcinoma in NAFLD patients is lacking. This review therefore addresses the potential beneficial effects of metformin on NAFLD, its role in protecting against cardiac ischemia–reperfusion (I/R) injury, atherosclerosis, glucotoxicity, and lipotoxicity induced oxidative and ER stress in pancreatic β-cell dysfunction, as well as its underlying molecular mechanisms of action.

Effects of dapagliflozin and n-3 carboxylic acids on non-alcoholic fatty liver disease in people with type 2 diabetes: a double-blind randomised placebo-controlled study

AIMS/HYPOTHESIS

The EFFECT-II study aimed to investigate the effects of dapagliflozin and omega-3 (n-3) carboxylic acids (OM-3CA), individually or combined, on liver fat content in individuals with type 2 diabetes and non-alcoholic fatty liver disease (NAFLD).

METHODS

This randomised placebo-controlled double-blind parallel-group study was performed at five clinical research centres at university hospitals in Sweden. 84 participants with type 2 diabetes and NAFLD were randomly assigned 1:1:1:1 to four treatments by a centralised randomisation system, and all participants as well as investigators and staff involved in the study conduct and analyses were blinded to treatments. Each group received oral doses of one of the following: 10 mg dapagliflozin (n = 21), 4 g OM-3CA (n = 20), a combination of both (n = 22) or placebo (n = 21). The primary endpoint was liver fat content assessed by MRI (proton density fat fraction [PDFF]) and, in addition, total liver volume and markers of glucose and lipid metabolism as well as of hepatocyte injury and oxidative stress were assessed at baseline and after 12 weeks of treatment (completion of the trial).

RESULTS

Participants had a mean age of 65.5 years (SD 5.9), BMI 31.2 kg/m² (3.5) and liver PDFF 18% (9.3). All active treatments significantly reduced liver PDFF from baseline, relative changes: OM-3CA, -15%; dapagliflozin, -13%; OM-3CA + dapagliflozin, -21%. Only the combination treatment reduced liver PDFF (p = 0.046) and total liver fat volume (relative change, -24%, p = 0.037) in comparison with placebo. There was an interaction between the PNPLA3 I148M polymorphism and change in liver PDFF in the active treatment groups (p = 0.03). Dapagliflozin monotherapy, but not the combination with OM-3CA, reduced the levels of hepatocyte injury biomarkers, including alanine aminotransferase, aspartate aminotransferase, γ-glutamyl transferase (γ-GT), cytokeratin (CK) 18-M30 and CK 18-M65 and plasma fibroblast growth factor 21 (FGF21). Changes in γ-GT correlated with changes in liver PDFF (ρ = 0.53, p = 0.02). Dapagliflozin alone and in combination with OM-3CA improved glucose control and reduced body weight and abdominal fat volumes. Fatty acid oxidative stress biomarkers were not affected by treatments. There were no new or unexpected adverse events compared with previous studies with these treatments.

CONCLUSIONS/INTERPRETATION

Combined treatment with dapagliflozin and OM-3CA significantly reduced liver fat content. Dapagliflozin monotherapy reduced all measured hepatocyte injury biomarkers and FGF21, suggesting a disease-modifying effect in NAFLD.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02279407 FUNDING: The study was funded by AstraZeneca.

Nonalcoholic Fatty Liver Disease and Diabetes Are Associated with Decreased CYP3A4 Protein Expression and Activity in Human Liver

Nonalcoholic fatty liver disease (NAFLD) is a major cause of chronic liver disease in the Western population. We investigated the association of nonalcoholic fatty liver disease (NAFLD) and diabetes mellitus on CYP3A4 activity in human liver tissue from brain dead donors ( n = 74). Histopathologically graded livers were grouped into normal ( n = 24), nonalcoholic fatty liver (NAFL, n = 26), and nonalcoholic steatohepatitis (NASH, n = 24) categories. The rate of conversion of midazolam to its 1-hydroxy metabolite was used to assess in vitro CYP3A4 activity in human liver microsomes (HLM). A proteomics approach was utilized to quantify the protein expression of CYP3A4 and related enzymes. Moreover, a physiologically based pharmacokinetic (PBPK) model was developed to allow prediction of midazolam concentration in NAFL and NASH livers. CYP3A4 activity in NAFL and NASH was 1.9- and 3.1-fold ( p < 0.05) lower than normal donors, respectively. Intrinsic clearance (CLint) was 2.7- ( p < 0.05) and 4.1-fold ( p < 0.01) lower in donors with NAFL and NASH, respectively. CYP3A4 protein expression was significantly lower in NAFL and NASH donors ( p < 0.05) and accounted for significant midazolam hydroxylation variability in a multiple linear regression analysis (β = 0.869, r² = 0.762, P < 0.01). Diabetes was also associated with decreased CYP3A4 activity and protein expression. Both midazolam CLint and CYP3A4 protein abundance decreased significantly with increase in hepatic fat accumulation. Age and gender did not exhibit any significant association with the observed alterations. Predicted midazolam exposure was 1.7- and 2.3-fold higher for NAFL and NASH, respectively, which may result in a longer period of sedation in these disease-states. Data suggests that NAFLD and diabetes are associated with the decreased hepatic CYP3A4 activity. Thus, further evaluation of clinical consequences of these findings on the efficacy and safety of CYP3A4 substrates is warranted.

Current and future pharmacological therapies for NAFLD/NASH

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent liver disease worldwide, and there is no approved pharmacotherapy. The efficacy of vitamin E and pioglitazone has been established in nonalcoholic steatohepatitis (NASH), a progressive form of NAFLD. GLP-1RA and SGLT2 inhibitors, which are currently approved for use in diabetes, have shown early efficacy in NASH, and also have beneficial cardiovascular or renal effects. Innovative NASH therapies include four main pathways. The first approach is targeting hepatic fat accumulation. Medications in this approach include modulation of peroxisome proliferator-activator receptors (e.g., pemafibrate, elafibranor), medications targeting farnesoid X receptor axis [obeticholic acid; OCA)], inhibitors of de novo lipogenesis (aramchol, ACC inhibitor), and fibroblast growth factor-21 analogues. A second target is oxidative stress, inflammation, and apoptosis. This class of drug includes apoptosis signaling kinase 1 (ASK1) inhibitor and emricasan (an irreversible caspase inhibitor). A third target is intestinal microbiomes and metabolic endotoxemia. Several agents are in ongoing trials, including IMMe124, TLR4 antagonist, and solithromycin (macrolide antibiotics). The final target is hepatic fibrosis, which is strongly associated with all-cause or liver-related mortality in NASH. Antifibrotic agents are a cysteine-cysteine motif chemokine receptor-2/5 antagonist (cenicriviroc; CVC) and galectin 3 antagonist. Among a variety of medications in development, four agents such as OCA, elafibranor, ASK1 inhibitor, and CVC are currently being evaluated in an international phase 3 trial for the treatment of NASH. Within the next few years, the availability of therapeutic options for NASH will hopefully curb the rising trend of NASH-related diseases.

The Improvement of the Hepatic Histological Findings in a Patient with Non-alcoholic Steatohepatitis with Type 2 Diabetes after the Administration of the Sodium-glucose Cotransporter 2 Inhibitor Ipragliflozin

The patient was a 67-year-old woman with type 2 diabetes and non-alcoholic steatohepatitis (NASH). The administration of the sodium-glucose cotransporter 2 (SGLT2) inhibitor, ipragliflozin improved her liver dysfunction clinically and histologically. The serum alanine aminotransferase (ALT) and ferritin levels decreased to normal limits after treatment for four months. Type IV collagen and hyaluronic acid, both of which were serum fibrotic markers, decreased after treatment. Ultrasonography and computed tomography showed a decrease in the fat deposits in her liver. Her liver sample showed marked improvement, especially in steatosis, inflammation, and ballooning. The SGLT2 inhibitor ipragliflozin may be useful as a specific therapeutic drug for NASH.