Efficacy of Sodium-Glucose Cotransporter 2 Inhibitors in Patients With Concurrent Type 2 Diabetes Mellitus and Non-Alcoholic Steatohepatitis: A Review of the Evidence

Steatotic Liver Disease: Pathophysiology and Emerging Pharmacotherapies

Steatotic liver disease (SLD) displays a dynamic and complex disease phenotype. Consequently, the metabolic dysfunction-associated steatotic liver disease (MASLD)/metabolic dysfunction-associated steatohepatitis (MASH) therapeutic pipeline is expanding rapidly and in multiple directions. In parallel, noninvasive tools for diagnosing and monitoring responses to therapeutic interventions are being studied, and clinically feasible findings are being explored as primary outcomes in interventional trials. The realization that distinct subgroups exist under the umbrella of SLD should guide more precise and personalized treatment recommendations and facilitate advancements in pharmacotherapeutics. This review summarizes recent updates of pathophysiology-based nomenclature and outlines both effective pharmacotherapeutics and those in the pipeline for MASLD/MASH, detailing their mode of action and the current status of phase 2 and 3 clinical trials. Of the extensive arsenal of pharmacotherapeutics in the MASLD/MASH pipeline, several have been rejected, whereas other, mainly monotherapy options, have shown only marginal benefits and are now being tested as part of combination therapies, yet others are still in development as monotherapies. Although the Food and Drug Administration (FDA) has recently approved resmetirom, additional therapeutic approaches in development will ideally target MASH and fibrosis while improving cardiometabolic risk factors. Due to the urgent need for the development of novel therapeutic strategies and the potential availability of safety and tolerability data, repurposing existing and approved drugs is an appealing option. Finally, it is essential to highlight that SLD and, by extension, MASLD should be recognized and approached as a systemic disease affecting multiple organs, with the vigorous implementation of interdisciplinary and coordinated action plans. SIGNIFICANCE STATEMENT: Steatotic liver disease (SLD), including metabolic dysfunction-associated steatotic liver disease and metabolic dysfunction-associated steatohepatitis, is the most prevalent chronic liver condition, affecting more than one-fourth of the global population. This review aims to provide the most recent information regarding SLD pathophysiology, diagnosis, and management according to the latest advancements in the guidelines and clinical trials. Collectively, it is hoped that the information provided furthers the understanding of the current state of SLD with direct clinical implications and stimulates research initiatives.

Diagnosis of hepatic steatosis and steatohepatitis in people with new-onset type 2 diabetes: a multidisciplinary approach

AIMS

Non-Alcoholic-Fatty-Liver-Disease (NAFLD) is the most common cause of chronic liver disease in Western countries; closely linked to obesity and type 2 diabetes (T2DM), it is an additional cardiovascular risk factor. The aim of this study is to investigate the prevalence of NAFLD at T2DM onset.

METHODS

122 newly diagnosed T2DM patients were enroled; NAFLD was diagnosed using ultrasound and fibrosis risk calculated with an FIB4-score. Intermediate and high-risk patients were referred to a hepatologist and underwent transient elastography (TE).

RESULTS

At T2DM diagnosis, 25% of patients were overweight, 47% were obese; ultrasound steatosis was present in 79% of patients; the average FIB-4 score was 1.4 (0.7). The NAFLD population was characterised by higher presence of obesity (60%, p 0.06); hypertension (56%, p 0.00); AST (26.3 (23.6) UI/L; p 0.00); ALT (49.3(41.0) UI/L p 0.00); FIB-4 score (1.6 (0.8); p 0.00). Among patients referred to a hepatologist, at TE, 65% had severe steatosis, 22% significant fibrosis and 25% advanced fibrosis.

CONCLUSION

This is the first proposal of a NAFLD screening model at T2DM diagnosis. The high prevalence of fibrosis found at the early stage T2DM confirms the compelling need for early management of NAFLD through cost-effective screening and long-term monitoring algorithms.

SGLT2 inhibitors and AMPK: The road to cellular housekeeping?

Sodium-glucose co-transporter-2 (SGLT2) inhibitors, known as Gliflozins, are a class of Glucose-lowering drugs in adults with type 2 diabetes (T2D) that induce glucosuria by blocking SGLT2 co-transporters in the proximal tubules. Several lines of evidence suggest that SGLT2 inhibitors regulate multiple mechanisms associated with the regulation of varying cellular pathways. The 5'-adenosine monophosphate-activated protein kinase (AMPK) pathway plays an important role in metabolic homeostasis by influencing cellular processes. Recently, it has been shown that SGLT2 inhibitors can affect the AMPK pathway in differing physiological and pathological ways, resulting in kidney, intestinal, cardiovascular, and liver protective effects. Additionally, they have therapeutic effects on nonalcoholic fatty liver disease and diabetes mellitus-associated complications. In this review, we summarize the results of studies of AMPK-associated therapeutic effects of SGLT2 inhibitors in different organelle functions.

Effect of Policaptil Gel Retard on Liver Fat Content and Fibrosis in Adults with Metabolic Syndrome and Type 2 Diabetes: A Non-invasive Approach to MAFLD

INTRODUCTION

Non-alcoholic fatty liver disease (NAFLD) is part of a disease spectrum ranging from steatosis to steatohepatitis (NASH), fibrosis, and cirrhosis, and when associated with metabolic syndrome (MS), and overt diabetes is defined as metabolic NAFLD (MAFLD). Some easily available, inexpensive biomarkers have been validated based on common anthropometric and laboratory parameters, including the Fatty Liver Index (FLI), the Fibrosis (FIB)-4 Score (FIB-4), and the NAFLD Fibrosis Score (NFS). In people with overweight/obesity, MS, and diabetes, the pathogenesis of fatty liver involves parameters known to be positively affected by Policaptil Gel Retard (PGR), a phytocomplex already successfully used in adolescents and adults with MS and type 2 diabetes mellitus (T2DM). This study's primary outcome was to assess PGR's ability to improve indirect validated signs of liver steatosis and fibrosis, i.e., FLI, FIB-4, and NFS Scores; as the secondary outcome, we aimed to confirm PGR's positive effects on anthropometric parameters and lipid levels and to assess any eventually occurring cytolysis liver marker changes in patients with MS/T2DM and MAFLD/NASH.

METHODS

In this spontaneous, longitudinal, single-blind, randomized clinical study, 245 outpatients with MS/T2DM were enrolled and randomized to PGR or placebo for 24 weeks. All underwent a low-calorie diet (20-25% less than the calories required to maintain current weight) and were encouraged to intensify physical activity. Fat distribution, liver fat content/fibrosis, and biochemical parameters were evaluated at baseline and after 24 weeks.

RESULTS

Our data show for the first time in adults with MAFLD that, when added to lifestyle changes including a hypocaloric diet and intensified physical activity, PGR improves lipid and glucose metabolism-related parameters, including insulin-resistance, and significantly reduces not only visceral fat but also liver fat content and related liver fibrosis severity. The prevalence of subjects with severe steatosis (FLI > 60) significantly decreased from 95.08 to 47.53% (p < 0.001) only in the treatment group, which also displayed a significantly decreased prevalence of medium-severe cases (F3-F4) from 83.62% to 52.35% (p < 0.001) and a markedly increased prevalence of low degree cases (F0-F1) from 9.01 to 42.15% (p < 0.001).

CONCLUSIONS

The effect of PGR is related to a reduction in the post-meal blood glucose and insulin peaks. As glucose absorption (GA) directly regulates pancreatic insulin release, the attenuated insulin response is likely due to delayed GA with decreased body weight, visceral fat, and cardiovascular risk. Also, an effect on the intestinal microbiota, already documented in the animal model, cannot be excluded, especially considering the reported PGR-related shift from the Firmicutes, notoriously responsible for increased lipid gut absorption, to the Bacteroides phylum.

The Ketogenic Effect of SGLT-2 Inhibitors-Beneficial or Harmful?

Sodium-glucose cotransporter-2 (SGLT-2) inhibitors, also called gliflozins or flozins, are a class of drugs that have been increasingly used in the management of type 2 diabetes mellitus (T2DM) due to their glucose-lowering, cardiovascular (CV), and renal positive effects. However, recent studies suggest that SGLT-2 inhibitors might also have a ketogenic effect, increasing ketone body production. While this can be beneficial for some patients, it may also result in several potential unfavorable effects, such as decreased bone mineral density, infections, and ketoacidosis, among others. Due to the intricate and multifaceted impact caused by SGLT-2 inhibitors, this initially anti-diabetic class of medications has been effectively used to treat both patients with chronic kidney disease (CKD) and those with heart failure (HF). Additionally, their therapeutic potential appears to extend beyond the currently investigated conditions. The objective of this review article is to present a thorough summary of the latest research on the mechanism of action of SGLT-2 inhibitors, their ketogenesis, and their potential synergy with the ketogenic diet for managing diabetes. The article particularly discusses the benefits and risks of combining SGLT-2 inhibitors with the ketogenic diet and their clinical applications and compares them with other anti-diabetic agents in terms of ketogenic effects. It also explores future directions regarding the ketogenic effects of SGLT-2 inhibitors.

Therapies for patients with coexisting heart failure with reduced ejection fraction and non-alcoholic fatty liver disease

Heart failure with reduced ejection fraction (HFrEF) and nonalcoholic fatty liver disease (NAFLD) are two common comorbidities that share similar pathophysiological mechanisms. There is a growing interest in the potential of targeted therapies to improve outcomes in patients with coexisting HFrEF and NAFLD. This manuscript reviews current and potential therapies for patients with coexisting HFrEF and NAFLD. Pharmacological therapies, including angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, mineralocorticoids receptor antagonist, and sodium-glucose cotransporter-2 inhibitors, have been shown to reduce fibrosis and fat deposits in the liver. However, there are currently no data showing the beneficial effects of sacubitril/valsartan, ivabradine, hydralazine, isosorbide nitrates, digoxin, or beta blockers on NAFLD in patients with HFrEF. This study highlights the importance of considering HFrEF and NAFLD when developing treatment plans for patients with these comorbidities. Further research is needed in patients with coexisting HFrEF and NAFLD, with an emphasis on novel therapies and the importance of a multidisciplinary approach for managing these complex comorbidities.

Sodium-Glucose Cotransporter-2 Inhibitors in Depression

ABSTRACT

Novel treatment strategies that refract existing treatment algorithms for depressive disorders are being sought. Abnormal brain bioenergetic metabolism may represent an alternative, therapeutically targetable neurobiological basis for depression. A growing body of research points to endogenous ketones as candidate neuroprotective metabolites with the potential to enhance brain bioenergetics and improve mood. Sodium-glucose cotransporter-2 (SGLT2) inhibitors, originally approved for the treatment of diabetes, induce ketogenesis and are associated with mood improvement in population-based studies. In this column, we highlight the rationale for the hypothesis that ketogenesis induced by SGLT2 inhibitors may be an effective treatment for depressive disorders.

Factors related to hypermetabolism in individuals with type 2 diabetes mellitus and non-alcoholic fatty liver disease

Considering the progressive prevalence and co-occurrence of type 2 diabetes mellitus (T2DM) and non-alcoholic fatty liver disease (NAFLD), as well as the current evidence suggesting the elevated levels of basal metabolic rate (BMR) among these individuals, the present study aimed to identify factors determining hypermetabolism in such subjects. This cross sectional study was conducted in 30 to 53-year-old individuals with concurrent T2DM and NAFLD (controlled attenuation parameter score ≥ 260 dB/m). Resting energy expenditure (REE) was determined by an indirect calorimetry device. Hypermetabolism was defined as an elevated measured REE > 110% of the predicted REE. The multivariate logistic regression test was used for detecting factors associated with hypermetabolism. Between September, 2017, and March, 2018, a total of 95 eligible participants (64.40% male) with both T2DM and NAFLD were included, while 32.63% of them were classified as hypermetabolic. Overall, the mean recruitment age ± standard deviation and median (interquartile range) body mass index were 44.69 ± 5.47 years and 30.20 (27.80-33.30) kg/m², respectively. Demographic, anthropometric and biochemical variables did not vary significantly across two groups except for total body water, low-density lipoprotein cholesterol and dipeptidyl peptidase 4 (DPP-4) inhibitors (p < 0.05). According to the results of multivariable logistic regression analyses, hypermetabolism had a positive association with adiponectin (odds ratio [OR] 1.167, 95% confidence interval [CI] 1.015-1.342, p = 0.030), physical activity (OR 1.134, 95% CI 1.002-1.284, p = 0.046), alanine transaminase (OR 1.062, 95% CI 1.006-1.122, p = 0.031) and diastolic blood pressure (OR 1.067, 95% CI 1.010-1.127, p = 0.021). However, fat free mass was inversely related to hypermetabolism (OR 0.935, 95% CI 0.883-0.991, p = 0.023). Adiponectin, alanine transaminase, physical activity, diastolic blood pressure and fat free mass were independently associated with hypermetabolism in subjects with NAFLD and T2DM.

The effect of metabolic dysfunction-associated fatty liver disease and diabetic kidney disease on the risk of hospitalization of heart failure in type 2 diabetes: a retrospective cohort study

BACKGROUND

Diabetes mellitus is a major risk factor for heart failure. A recent consensus statement recommended annual cardiac biomarker testing (e.g. natriuretic peptide or high-sensitivity cardiac troponin) for all patients with diabetes. We aimed to identify patients at a higher risk of hospitalization for heart failure among patients with type 2 diabetes to prioritize those who would require screening.

METHODS

Overall, 1,189,113 patients who underwent two medical health checkup cycles (2009-2012 and 2011-2014) and had stable diabetic kidney disease (DKD) phenotype in the Korean National Health Insurance Service database were included in this study. After excluding those with concurrent proteinuria (PU) and reduced estimated glomerular filtration rate, three groups (no-DKD, PU⁺DKD, and PU^-DKD) were identified. A fatty liver index of ≥ 60 was defined as metabolic dysfunction-associated fatty liver disease (MAFLD). Patients were followed up until December 2018 or until outcomes developed. The Cox proportional hazard model was used to compare the risk of hospitalization for heart failure across groups.

RESULTS

During an average of 6.6 years of follow-up, 5781 patients developed hospitalization for heart failure. After adjusting for covariates, the risk of hospitalization for heart failure was highest in the PU⁺DKD group [HR 3.12, 95% CI (2.75-3.55)], followed by the PU^-DKD group [HR 1.85, 95% CI (1.73-1.99)] using the no-DKD group as the reference category. The risk of hospitalization for heart failure was comparable regardless of MAFLD status in patients who already had DKD. However, in the no-DKD group, the risk of hospitalization for heart failure was 1.4 times higher in patients with MAFLD than in those without [HR 1.41, 95% CI (1.31-1.52)].

CONCLUSIONS

In lines with the international consensus statement, we suggest that annual cardiac biomarker testing should be conducted at least in patients with DKD and/or MAFLD.

Lessons on Drug Development: A Literature Review of Challenges Faced in Nonalcoholic Fatty Liver Disease (NAFLD) Clinical Trials

NAFLD is the most common chronic liver disease worldwide, occurring in both obese and lean patients. It can lead to life-threatening liver diseases and nonhepatic complications, such as cirrhosis and cardiovascular diseases, that burden public health and the health care system. Current care is weight loss through diet and exercise, which is a challenging goal to achieve. However, there are no FDA-approved pharmacotherapies for NAFLD. This review thoroughly examines the clinical trial findings from 22 drugs (Phase 2 and above) and evaluates the future direction that trials should take for further drug development. These trialed drugs can broadly be categorized into five groups-hypoglycemic, lipid-lowering, bile-pathway, anti-inflammatory, and others, which include nutraceuticals. The multitude of challenges faced in these yet-to-be-approved NAFLD drug trials provided insight into a few areas of improvement worth considering. These include drug repurposing, combinations, noninvasive outcomes, standardization, adverse event alleviation, and the need for precision medicine with more extensive consideration of NAFLD heterogenicity in drug trials. Understandably, every evolution of the drug development landscape lies with its own set of challenges. However, this paper believes in the importance of always learning from lessons of the past, with each potential improvement pushing clinical trials an additional step forward toward discovering appropriate drugs for effective NAFLD management.

SGLT2 Inhibitors as the Most Promising Influencers on the Outcome of Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD), the most frequent liver disease in the Western world, is a common hepatic manifestation of metabolic syndrome (MetS). A specific cure has not yet been identified, and its treatment is currently based on risk factor therapy. Given that the initial accumulation of triglycerides in the liver parenchyma, in the presence of inflammatory processes, mitochondrial dysfunction, lipotoxicity, glucotoxicity, and oxidative stress, can evolve into non-alcoholic steatohepatitis (NASH). The main goal is to identify the factors contributing to this evolution because, once established, untreated NASH can progress through fibrosis to cirrhosis and, ultimately, be complicated by hepatocellular carcinoma (HCC). Several drugs have been tested in clinical trials for use as specific therapy for NAFLD; most of them are molecules used to cure type 2 diabetes mellitus (T2DM), which is one of the main risk factors for NAFLD. Among the most studied is pioglitazone, either alone or in combination with vitamin E, glucagon-like peptide-1 (GLP-1) receptor agonists, dipeptidyl peptidase-4 (DPP-4) inhibitors. Actually, the most promising category seems to be sodium-glucose cotransporter (SGLT2) inhibitors. Their action is carried out by inhibiting glucose reabsorption in the proximal renal tubule, leading to its increased excretion in urine and decreased levels in plasma. Experimental studies in animal models have suggested that SGLT2 inhibitors may have beneficial modulatory effects on NAFLD/NASH, and several trials in patients have proven their beneficial effects on liver enzymes, BMI, blood lipids, blood glucose, and insulin resistance in NAFLD patients, thus creating strong expectations for their possible use in preventing the evolution of liver damage in these patients. We will review the main pathogenetic mechanisms, diagnostic modalities, and recent therapies of NAFLD, with particular attention to the use of SGLT2 inhibitors.