Nonalcoholic fatty liver disease: multimodal treatment options for a pathogenetically multiple-hit disease

Osteokines in Nonalcoholic Fatty Liver Disease

PURPOSE OF REVIEW

To critically summarize evidence on the potential role of osteokines in the pathogenesis and progression of nonalcoholic fatty liver disease (NAFLD).

RECENT FINDINGS

There are emerging data supporting that certain osteokines, which are specific bone-derived proteins, may beneficially or adversely affect hepatic metabolism, and their alterations in the setting of osteoporosis or other bone metabolic diseases may possibly contribute to the development and progression of NAFLD. There is evidence showing a potential bidirectional association between NAFLD and bone metabolism, which may imply the existence of a liver-bone axis. In this regard, osteocalcin, osteoprotegerin, bone morphogenic protein 4 (BMP4) and BMP6 appear to have a positive impact on the liver, thus possibly alleviating NAFLD, whereas osteopontin, receptor activator of nuclear factor kappa Β ligand (RANKL), sclerostin, periostin, BMP8B, and fibroblast growth factor 23 (FGF23) appear to have a negative impact on the liver, thus possibly exacerbating NAFLD. The potential implication of osteokines in NAFLD warrants further animal and clinical research in the field that may possibly result in novel therapeutic targets for NAFLD in the future.

Menopause and metabolic dysfunction-associated steatotic liver disease

Nonalcoholic fatty liver disease, recently proposed to be renamed metabolic dysfunction-associated steatotic liver disease, is a highly prevalent disease (25-30 % of the global general population) whose prevalence increases after menopause. Apart from the rates of simple steatosis, the severity of the disease (e.g., hepatic fibrosis) increases after menopause. Menopause is associated with higher abdominal adiposity and dysmetabolism of carbohydrate and lipid metabolism, which may contribute to the development and severity of metabolic dysfunction-associated steatotic liver disease and the higher cardiovascular risk observed after menopause. The association between menopause and metabolic dysfunction-associated steatotic liver disease renders menopausal hormone therapy an appealing way to reverse hepatic disease in parallel with the benefits of menopausal hormone therapy in other tissues. In this regard, most animal studies have shown a beneficial effect of estrogens on metabolic dysfunction-associated steatotic liver disease. Still, clinical studies are few, and their data are conflicting. The effect of menopausal hormone therapy on metabolic dysfunction-associated steatotic liver disease may be distinct among estrogen monotherapies and the combinations of estrogens and progestogens. It may also depend on the type of progestogen and the route of administration. However, more studies specifically designed for these aims are needed to draw secure conclusions. This review summarizes the data related to the association between menopause and metabolic dysfunction-associated steatotic liver disease, as well as between menopausal hormone therapy and metabolic dysfunction-associated steatotic liver disease, with a special focus on clinical studies.

Partial validation of a six-month high-fat diet and fructose-glucose drink combination as a mouse model of nonalcoholic fatty liver disease

PURPOSE

The need to investigate the pathogenesis and treatment of nonalcoholic fatty liver disease (NAFLD) has led to the development of multiple mouse models. The aim of this study was to validate a fast food diet (FFD) mouse model that is introduced as being close to the human disease.

METHODS

Eight to nine weeks old male and female C57BL/6 J mice were randomly allocated to a FFD group or to a chow diet (CD) group. Every four weeks, mice were weighed, and blood samples were collected for the measurement of glucose, alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglycerides (TGs) and total cholesterol. After 25 weeks, mice were sacrificed, and liver tissue was histologically evaluated.

RESULTS

FFD mice gained more weight (p = 0.049) and presented a higher liver-to-body weight ratio (p < 0.001) compared to CD mice. FFD group presented with greater steatosis, hepatocellular ballooning and NAFLD activity score (NAS), whereas lobular inflammation and fibrosis were not significantly different compared to CD. When stratified by sex, NAS was different between FFD and CD groups in both male and female mice. Group by time interaction was significant for weight, ALT and cholesterol, but not for glucose, AST and TGs.

CONCLUSION

FFD mice presented with morphologic and biochemical features of NAFLD and with greater hepatic steatosis, hepatocellular ballooning and NAS, but not lobular inflammation and fibrosis, compared to CD mice. These results only partly validate the FFD mouse model for NAFLD, at least for a 6-month feeding period.

Role of Glucocorticoids in Metabolic Dysfunction-Associated Steatotic Liver Disease

PURPOSE OF THE REVIEW

To summarize published data on the association between glucocorticoids and metabolic dysfunction-associated steatotic liver disease (MASLD), focusing on the possible pathophysiological links and related treatment considerations.

RECENT FINDINGS

Glucocorticoids, commonly used for managing many inflammatory and autoimmune diseases, may contribute to the development and progression of MASLD. Glucocorticoids may induce hyperglycemia and hyperinsulinemia, thus increasing systemic and hepatic insulin resistance, a hallmark of MASLD pathogenesis. Furthermore, glucocorticoids increase adipose tissue lipolysis, and hepatic de novo lipogenesis and decrease hepatic fatty acid β-oxidation, thus promoting MASLD development. Preclinical evidence also suggests that glucocorticoids may adversely affect hepatic inflammation and fibrosis. 11beta-hydroxysteroid dehydrogenase type 1 (11β-HSD1) and 5α-reductase are implicated in the link between glucocorticoids and MASLD, the former enzyme increasing and the latter reducing the glucocorticoid action on the liver. Treatment considerations exist due to the pathogenic link between glucocorticoids and MASLD. Since iatrogenic hypercortisolism is common, glucocorticoids should be used at the minimum daily dose to control the subjective disease. Furthermore, the pharmacologic inhibition of 11β-HSD1 has provided favorable results in MASLD, both in preclinical studies and early MASH clinical trials. Glucocorticoids are closely linked to MASLD pathophysiology, with specific clinical and therapeutic implications.

Non-alcoholic fatty liver disease changes the expression and activity of hepatic drug-metabolizing enzymes and transporters in rats

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases, which can cause serious complications and gradually increase the mortality rate. However, the effects of NAFLD on drug-metabolizing enzymes and transporters remain unclear, which may cause some confusion regarding patient medication. In this study, a NAFLD rat model was constructed by feeding rats with methionine and choline deficiency diets for 6 weeks, and the mRNA and protein levels of drug-metabolizing enzymes and transporter were analyzed by real-time fluorescent quantitative PCR and Western blot, respectively. The activity of drug-metabolizing enzymes was detected by cocktail methods. In the NAFLD rat model, the mRNA expression of phase I enzymes, phase II enzymes, and transporters decreased. At the protein level, only CYP1A1, CYP1B1, CYP2C11, and CYP2J3 presented a decrease. In addition, the activities of CYP1A2, CYP2B1, CYP2C11, CYP2D1, CYP3A2, UGT1A1, UGT1A3, UGT1A6, and UGT1A9 decreased. These changes may be caused by the alteration of FXR, HNF4α, LXRα, LXRβ, PXR, and RXR. In conclusion, NAFLD changes the expression and activity of hepatic drug-metabolizing enzymes and transporters in rats, which may affect drug metabolism and pharmacokinetics. In clinical medication, drug monitoring should be strengthened to avoid potential risks.

Circulating leptin in patients with nonalcoholic fatty liver disease-related liver fibrosis: a systematic review and a meta-analysis

BACKGROUND AND AIM

Clinical data on the association between leptin levels and nonalcoholic fatty liver disease (NAFLD)-related liver fibrosis are conflicting. This meta-analysis aimed to compare circulating leptin between NAFLD patients with versus without liver fibrosis or non-NAFLD controls.

METHODS

A systematic search was conducted in PubMed, Scopus, and the Cochrane Library. Fifteen studies were included, reporting data from 964 individuals (422 NAFLD patients with fibrosis, 297 NAFLD patients without fibrosis, 245 no-NAFLD controls).

RESULTS

Leptin standardized mean difference (SMD) was higher in NAFLD patients with fibrosis (F1-F4) than in controls (SMD: 2.27; 95% confidence interval [CI]: 0.81-3.73); however, this association did not remain robust after the exclusion of studies with morbidly obese individuals. No difference was observed in leptin SMD between NAFLD patients with fibrosis and those without fibrosis (F0), and NAFLD patients without fibrosis versus controls. Heterogeneity was high (I2: 66-98%) among studies. Meta-regression analysis revealed a positive association of leptin SMD with homeostasis model assessment-insulin resistance, when comparing NAFLD patients with fibrosis versus NAFLD patients without fibrosis (beta: 0.53; 95% CI: 0.04-1.03), and a negative association of leptin SMD with age, when comparing NAFLD patients with fibrosis versus controls (beta: -0.29; 95% CI: -0.53 to -0.05).

CONCLUSION

Circulating leptin was higher in NAFLD patients with liver fibrosis than non-NAFLD controls, an association, however, attenuated after the exclusion of a study with morbidly obese individuals. Circulating leptin was not different between NAFLD patients with and without fibrosis, or NAFLD patients without fibrosis and controls.

A revisit of drugs and potential therapeutic targets against non-alcoholic fatty liver disease: learning from clinical trials

PURPOSE

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease, with a worldwide prevalence of 25%. Although numerous clinical trials have been conducted over the last few decades, an effective treatment has not been approved yet. Extensive research has accumulated a large amount of data and experience; however, the vast number of clinical trials and new therapeutic targets for NAFLD make it impossible to keep abreast of the relevant information. Therefore, a systematic analysis of the existing trials is necessary.

METHODS

Here, we reviewed clinical trials on NAFLD registered in the mandated federal database, ClinicalTrials.gov, to generate a detailed overview of the trials related to drugs and therapeutic targets for NAFLD treatment. Following screening for pertinence to therapy, a total of 440 entries were identified that included active trials as well as those that have already been completed, suspended, terminated, or withdrawn.

RESULTS

We summarize and systematically analyze the state, drug development pipeline, and discovery of treatment targets for NAFLD. We consider possible factors that may affect clinical outcomes. Furthermore, we discussed these results to explore the mechanisms responsible for clinical outcomes.

CONCLUSION

We summarised the landscape of current clinical trials and suggested the directions for future NAFLD therapy to assist internal medicine specialists in treating the whole clinical spectrum of this highly prevalent liver disease.

Animal studies on glucagon-like peptide-1 receptor agonists and related polyagonists in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is a prevalent metabolic liver disease closely associated with the epidemics of obesity and type 2 diabetes mellitus (T2DM), but without licensed pharmacological treatment to date. As glucagon-like peptide-1 (GLP-1) receptor agonists (GLP-1RAs) are approved anti-diabetic and anti-obesity medications, they were also considered a potential therapeutic option for NAFLD. Preclinical studies suggest that GLP-1RAs have a beneficial effect on major NAFLD histological outcomes, i.e., hepatic steatosis and inflammation, through multiple intrahepatic mechanisms, including increased fatty acid β-oxidation, activation of autophagy, suppression of inflammation, and oxidative stress. Data on hepatic fibrosis are limited or inconclusive, although some studies reported improvement in indices of fibrosis or prevention of fibrosis initiation or reduction of collagen deposition. Whether the positive impact of GLP-1RAs on hepatic histology is indirect, i.e., through their action on extrahepatic tissues, or whether their action is direct, i.e., through activating GLP-1R on the hepatocytes, is still a controversial issue. Alongside GLP-1RAs, newly emerging peptide polyagonists (i.e., synthetic molecules that combine the amino acid sequences of more than one peptide, thus having the ability to bind more than one receptor) are now being investigated in NAFLD with high expectations. This review summarizes the existing knowledge derived from animal studies on the effects of GLP-1RAs and GLP-1RA related peptide polyagonists on NAFLD in an attempt to illuminate areas of uncertainty and provide the groundwork for future animal and clinical research in the field.

Tumor Necrosis Factor-Alpha and Adiponectin in Nonalcoholic Fatty Liver Disease-Associated Hepatocellular Carcinoma

Nonalcoholic fatty liver disease (NAFLD) is emerging as an important risk factor for hepatocellular carcinoma (HCC), whose prevalence is rising. Although the mechanisms of progression from NAFLD to HCC are not fully elucidated, tumor necrosis factor-α (TNF-α) and adiponectin, as well as their interplay, which seems to be antagonistic, may contribute to the pathophysiology of NAFLD-associated HCC. TNF-α initially aims to protect against hepatocarcinogenesis, but during the progression of NAFLD, TNF-α is increased, thus probably inducing hepatocarcinogenesis in the long-term, when NAFLD is not resolved. On the other hand, adiponectin, which is expected to exert anti-tumorigenic effects, is decreased during the progression of the disease, a trend that may favor hepatocarcinogenesis, but is paradoxically increased at end stage disease, i.e., cirrhosis and HCC. These observations render TNF-α and adiponectin as potentially diagnostic biomarkers and appealing therapeutic targets in the setting of NAFLD-associated HCC, possibly in combination with systematic therapy. In this regard, combination strategy, including immune checkpoint inhibitors (ICIs) with anti-TNF biologics and/or adiponectin analogs or medications that increase endogenous adiponectin, may warrant investigation against NAFLD-associated HCC. This review aims to summarize evidence on the association between TNF-α and adiponectin with NAFLD-associated HCC, based on experimental and clinical studies, and to discuss relevant potential therapeutic considerations.

Sarcopenia, sarcopenic obesity and nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD), sarcopenia and sarcopenic obesity (SO) are highly prevalent conditions that may coexist, especially in the aging population, without any approved pharmacologic treatment for all of them. There are multiple pathophysiologic mechanisms suggested to explain an association between NAFLD and sarcopenia or SO, including alterations in the adipokines, cytokines, hepatokines and myokines, which may interplay with other factors, such as aging, diet and physical inactivity. In clinical terms, most observational studies support an association between NAFLD and sarcopenia or SO; importantly, there are few cohort studies indicating higher mortality in patients with NAFLD and sarcopenia. Their association also bears some treatment considerations: for example, pioglitazone or vitamin E, suggested as off label treatment for selected patients with nonalcoholic steatohepatitis, may be recommended in the coexistence of sarcopenia or SO, since limited evidence did not show adverse effects of them on sarcopenia and abdominal obesity. In this review, evidence linking sarcopenia and SO with NAFLD is summarized, with a special focus on clinical data. A synopsis of the major pathophysiological links between NAFLD and sarcopenia/SO is initially presented, followed by selected clinical studies and, finally, treatment considerations in patients with NAFLD and sarcopenia or SO are discussed.

The role of glucagon-like peptide-1 receptor agonists in nonalcoholic fatty liver disease

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) is a highly prevalent disease, associated with obesity, type 2 diabetes mellitus and dyslipidemia, which can lead to liver cirrhosis and hepatocellular carcinoma in some patients. Apart from lifestyle modifications, which are the cornerstone for its management, several drugs are under evaluation, including glucagon-like peptide-1 receptor agonists (GLP-R1RAs). In this review, we summarized major clinical data concerning the effects of GLP-1RAs on NAFLD, trying to highlight existing knowledge and to elucidate areas of uncertainty, thus providing clues to potential clinical implications and research.

AREAS COVERED

Selected clinical studies on GLP-R1As in NAFLD are presented in this narrative review.

EXPERT OPINION

There is evidence that treatment with GLP-R1As in NAFLD has beneficial effects on NAFLD, i.e. improvement in liver function tests and histological improvement in hepatic steatosis and inflammation, but not fibrosis. Further research is required toward the early use of GLP-R1Αs, i.e. in NAFLD patients without fibrosis to evaluate whether they may prevent the progression to fibrosis, or in patients with advanced disease in combination with other medications, which may have additive or even synergistic effects on NAFLD.

Unraveling the pathophysiologic role of galectin-3 in chronically injured liver

Galectin-3 (Gal-3) previously referred to as S-type lectins, is a soluble protein that specifically binds to β-galactoside carbohydrates with high specificity. Gal-3 plays a pivotal role in a variety of pathophysiological processes such as cell proliferation, inflammation, differentiation, angiogenesis, transformation and apoptosis, pre-mRNA splicing, metabolic syndromes, fibrosis, and host defense. The role of Gal-3 has also been implicated in liver diseases. Gal-3 is activated upon a hepatotoxic insult to the liver and its level has been shown to be upregulated in fatty liver diseases, inflammation, nonalcoholic steatohepatitis, fibrosis, cholangitis, cirrhosis, and hepatocellular carcinoma (HCC). Gal-3 directly interacts with the NOD-like receptor family, pyrin domain containing 3, and activates the inflammasome in macrophages of the liver. In the chronically injured liver, Gal-3 secreted by injured hepatocytes and immune cells, activates hepatic stellate cells (HSCs) in a paracrine fashion to acquire a myofibroblast like collagen-producing phenotype. Activated HSCs in the fibrotic liver secrete Gal-3 which acts via autocrine signaling to exacerbate extracellular matrix synthesis and fibrogenesis. In the stromal microenvironment, Gal-3 activates cancer cell proliferation, migration, invasiveness, and metastasis. Clinically, increased serum levels and Gal-3 expression were observed in the liver tissue of nonalcoholic steatohepatitis, fibrotic/cirrhotic, and HCC patients. The pathological role of Gal-3 has been experimentally and clinically reported in the progression of chronic liver disease. Therefore, this review discusses the pathological role of Gal-3 in the progression of chronic liver diseases.

Circulating adiponectin in patients with nonalcoholic fatty liver disease-related liver fibrosis: A systematic review and a meta-analysis

BACKGROUND AND AIM

There are conflicting data on adiponectin concentrations in nonalcoholic fatty liver disease (NAFLD). The main aim was to compare circulating total adiponectin concentrations in NAFLD patients with versus without liver fibrosis.

METHODS

A systematic search was performed in PubMed, Scopus, and Cochrane Library. Twenty-two studies comprising 1753 biopsy-proven NAFLD individuals (1290 with and 463 without fibrosis) were included in the meta-analysis.

RESULTS

There was no difference in adiponectin concentration between NAFLD patients with versus without fibrosis (standardized mean difference [SMD]: -0.15; 95% confidence interval [95% CI]: -0.35 to 0.05). Heterogeneity was moderate among studies (Ι² : 60%, P < 0.001); no risk of publication bias was observed (Egger's test; P = 0.37). The sensitivity analysis, performed after the exclusion of studies with (i) children/adolescents and morbidly obese patients (n = 3) and (ii) adiponectin measurement with other methods than enzyme-linked immunosorbent assay (ELISA) (n = 9), revealed significantly lower adiponectin concentrations in NAFLD patients with fibrosis (i) SMD: -0.23, 95% CI: -0.41 to -0.04; (ii) SMD: -0.30, 95% CI: -0.55 to -0.04, respectively). Meta-regression analysis revealed no significant association of adiponectin SMD with age, alanine aminotransferase, aspartate aminotransferase, γ-glutamyl-transferase, homeostasis model assessment insulin resistance and the proportion of men.

CONCLUSIONS

Overall, patients with NAFLD and fibrosis had similar adiponectin concentrations with patients with NAFLD without fibrosis. However, adiponectin concentration was lower in NAFLD patients with fibrosis than those without fibrosis within the adult patients without morbid obesity and in studies in which adiponectin was measured with the same method (ELISA).

Nonalcoholic fatty liver disease and osteoporosis: A potential association with therapeutic implications

Nonalcoholic fatty liver disease (NAFLD) and osteoporosis are two highly prevalent metabolic diseases. Increasing experimental evidence supports a pathophysiological link between NAFLD and osteoporosis. A key feature could be chronic, low-grade inflammation, which characterizes NAFLD and possibly affects bone metabolism. In this context, several factors, including but not limited to receptor activator of nuclear factor kappa-B ligand, osteoprotegerin, osteopontin and osteocalcin, may serve as mediators. In the clinical setting, most but not all epidemiological evidence indicates that NAFLD is associated with lower bone mineral density or osteoporosis in adults. Although an association between NAFLD and osteoporosis has not yet been established, and thus remains speculative, pharmacological considerations already exist. Some of the current and emerging pharmacological options for NAFLD have shown possible anti-osteoporotic properties (eg, vitamin E, obeticholic acid, semaglutide), while others (eg, pioglitazone, canagliflozin) have been associated with increased risk of fractures and may be avoided in patients with NAFLD and concomitant osteoporosis, especially those at high fracture risk. Conversely, some anti-osteoporotic medications (denosumab) might benefit NAFLD, while others (raloxifene) might adversely affect it and, consequently, may be avoided in patients with osteoporosis and NAFLD. If an association between NAFLD and osteoporosis is established, a medication that could target both diseases would be a great advancement. This review summarizes the main experimental and clinical evidence on the potential association between NAFLD and osteoporosis and focuses on treatment considerations derived from this potential association.

Menopausal hormone therapy in women with dyslipidemia and nonalcoholic fatty liver disease

The cessation of ovarian function is associated with an increase in abdominal adipose tissue, dyslipidemia, and nonalcoholic fatty liver disease (NAFLD), which may contribute to the augmented cardiovascular risk observed in postmenopausal women. After ovarian function stops, circulating triglyceride, total cholesterol, and low-density lipoprotein-cholesterol (LDL-C) concentrations increase, whereas high-density lipoprotein-cholesterol (HDL-C) and lipoprotein (Lp(a)) remain essentially unchanged. Similarly, the rates of NAFLD, possibly including the advanced forms of the disease (e.g., hepatic fibrosis), increase in postmenopausal compared with premenopausal women. These effects make menopausal hormone therapy (MHT) an attractive way to restore them. Estrogen per os decreases LDL-C and Lp(a) and increases HDL-C and triglyceride concentrations. The transdermal administration of estrogen has a more neutral effect on triglycerides, albeit a less beneficial effect on LDL-C, HDL-C, and Lp(a). Co-administration of a progestagen diminishes the effect of estrogen on LDL-C, HDL-C, and Lp(a), which, however, remains beneficial. Importantly, the effect may vary with different progestagens, being lesser with natural progesterone and dydrogesterone. Regarding the effect of MHT on NAFLD, though experimental data are currently favorable, clinical evidence is to date limited and controversial. Therefore, there is a need for specifically designed clinical trials, ideally with paired liver biopsies, to demonstrate the effect of different MHT schemes on NAFLD, which is of considerable importance, given that NAFLD is more prevalent after the cessation of ovarian function.

Anti-obesity Medications for the Management of Nonalcoholic Fatty Liver Disease

PURPOSE OF REVIEW

Obesity is closely associated with nonalcoholic fatty liver disease (NAFLD), a highly prevalent disease without any approved medication. The aim of this review was to summarize the evidence on the effect of anti-obesity medications on NAFLD, especially focusing on hepatic histology.

RECENT FINDINGS

Orlistat and some glucagon-like peptide-1 receptor analogs, including liraglutide and semaglutide, have beneficial effects on hepatic steatosis and inflammation, but not fibrosis. Other anti-obesity medications, including lorcaserin, setmelanotide, phentermine hydrochloric, phentermine/topiramate, and naltrexone/bupropion, have been minimally investigated in NAFLD. Furthermore, medications like sodium-glucose cotransporter-2 inhibitors and farnesoid X receptor have shown beneficial effects in both NAFLD and obesity, but they have not been licensed for either disease. Liraglutide, semaglutide, and orlistat may be currently used in selected patients with obesity and NAFLD. Further research is warranted, since targeting obesity may provide additional benefits on its comorbidities, including NAFLD.

Total Flavonoids from Chimonanthus nitens Oliv. Leaves Ameliorate HFD-Induced NAFLD by Regulating the Gut–Liver Axis in Mice

Non-alcoholic fatty liver disease (NAFLD) is one of the chronic liver diseases with high incidence in the world. This study aimed to investigate whether total flavonoids from Chimonanthus nitens Oliv. leaves (TFC) can ameliorate NAFLD. Herein, a high-fat diet (HFD)-induced NAFLD mice model was established, and TFC was administered orally. The results showed that TFC reduced the body weight and liver index and decreased the serum and hepatic levels of triglyceride (TG) and total cholesterol (TC). TFC significantly reduced the activity of liver functional transaminase. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) decreased by 34.61% and 39.57% in serum and 22.46% and 40.86% in the liver, respectively. TFC regulated the activities of oxidative-stress-related enzymes and upregulated the protein expression of nuclear factor E2-related factor (Nrf2)/heme oxygenase (HO-1) pathway in NAFLD mice, and the activities of total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-PX) in serum were increased by 89.76% and 141.77%, respectively. In addition, TFC reduced the levels of free fatty acids (FFA), endotoxin (ET), and related inflammatory factors in mouse liver tissue and downregulated the expression of proteins associated with inflammatory pathways. After TFC treatment, the levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-1β in the liver tissues of NAFLD mice were downregulated by 67.10%, 66.56%, and 61.45%, respectively. Finally, TFC reduced liver fat deposition, oxidative stress, and inflammatory response to repair liver damage and alleviate NAFLD. Further studies showed that TFC regulated the expression of intestinal-barrier-related genes and improved the composition of gut microbiota. Therefore, TFC reduced liver inflammation and restored intestinal homeostasis by regulating the gut–liver axis. Overall, our findings revealed a novel function of TFC as a promising prophylactic for the treatment of NAFLD.

Combination Therapies for Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is considered a highly prevalent disease associated with various co-morbidities that lead to socioeconomic burden. Despite large-scale investigation, no pharmacological treatment has been approved specifically for NAFLD to date. Lifestyle modifications and diet are regarded as highly beneficial for the management of NAFLD, albeit with poor compliance, thus rendering pharmacological treatment highly important. Based on the current failure to discover a “magic bullet” to treat all patients with NAFLD and considering the multifaceted pathophysiology of the disease, combination therapies may be considered to be a rational alternative approach. In this regard, several drug categories have been considered, including, but not limited to, lipid-lowering, anti-hypertensive, glucose-lowering, anti-obesity, anti-oxidant, anti-inflammatory and anti-fibrotic medications. The aim of this review is, in addition to summarizing some of the multiple factors contributing to the pathophysiology of NAFLD, to focus on the efficacy of pharmacological combinations on the management of NAFLD. This may provide evidence for a more personalized treatment of patients with NAFLD in the future.

Nonalcoholic fatty liver disease: lifestyle and quality of life

Nonalcoholic fatty liver disease (NAFLD) is a metabolic disorder whose current rapidly expanding prevalence is causing it to develop into a major global health concern. NAFLD is closely linked to the modern, unhealthy lifestyle. The Western diet, characterized by excessive energy intake, frequent consumption of red meat, processed meat and foods, soft drinks, and sugar-sweetened beverages (SSBs), irregular meal distribution throughout the day, and unhealthy ways of cooking, predisposes to development of NAFLD. Low levels of physical activity and prolonged sedentary time are additional lifestyle risk factors for NAFLD. Given the present lack of effective pharmacological treatment, lifestyle modifications are regarded as the cornerstone of NAFLD management. Reducing daily calorie intake together with following the Mediterranean diet (MD) is an increasingly accepted approach. Furthermore, increasing the level of physical activity and limiting sedentary behavior are additional measures proposed to improve the outcomes of the disease. Apart from being affected by lifestyle, NAFLD may also affect patients' quality of life (QoL), mostly in the domain of physical function. In this regard, while the early and more benign form of the disease, i.e., simple hepatic steatosis, may not affect QoL, there is evidence, though conflicting, of the impact of nonalcoholic steatohepatitis (NASH) on this index, with, however, most studies showing that QoL is consistently affected in advanced disease, i.e., hepatic fibrosis, cirrhosis, and hepatocellular carcinoma. Considering all the above, appropriate management of lifestyle is likely to attenuate the severity of the disease and improve the QoL of NAFLD patients.

Dietary Selenium Alleviated Mouse Liver Oxidative Stress and NAFLD Induced by Obesity by Regulating the KEAP1/NRF2 Pathway

Nonalcoholic fatty liver disease (NAFLD) occurs when excess fat is stored in the liver and it is strongly linked with metabolic syndrome and oxidative stress. Selenium (Se) is an essential micronutrient in animals, which has a variety of biological functions, including antioxidant and anti-inflammatory. However, the exact effect of dietary selenium on NAFLD and the underlying molecular mechanism are not yet clear. Herein, we fed a high-fat diet (HFD) to C57BL/6 mice to construct an in vivo NAFLD model, treated AML-12 cells with palmitic acid (PA) to construct an in vitro NAFLD model, and AML-12 cells were stimulated with H₂O₂ to induce hepatocyte oxidative stress and then treated with adequate selenium. We observed that adequate selenium significantly improved the hepatic injury and insulin resistance in HFD mice, and decreased the fat accumulation and the expression of lipogenic genes in PA-induced AML-12 cells. Meanwhile, selenium significantly inhibited the production of reactive oxygen species (ROS), inhibited apoptosis, and restored mitochondrial number and membrane potential in PA- induced AML-12 cells. In addition, selenium can promote selenoproteinP1 (SEPP1) synthesis to regulate the Kelch-like ECH-associated protein 1 (KEAP1)/NF-E2-related factor 2 (NRF2) pathway, so as to defend against hepatocyte oxidative stress. These findings suggest that dietary selenium supplementation can effectively resist hepatic injury and insulin resistance during NAFLD development, and regulate the KEAP1/NRF2 pathway to resist oxidative stress by promoting SEPP1 synthesis.

Jaboticaba (Myrciaria jaboticaba) powder consumption improves the metabolic profile and regulates gut microbiome composition in high-fat diet-fed mice

The consumption of a high-fat diet can cause metabolic syndrome and induces host gut microbial dysbiosis and non-alcoholic fatty liver disease (NAFLD). We evaluated the effect of polyphenol-rich jaboticaba peel and seed powder (JPSP) on the gut microbial community composition and liver health in a mouse model of NAFLD. Three-month-old C57BL/6 J male mice, received either a control (C, 10% of lipids as energy, n = 16) or high-fat (HF, 50% of lipids as energy, n = 64) diet for nine weeks. The HF mice were randomly subdivided into four groups (n = 16 in each group), three of which (HF-J5, HF-J10, and HF-J15) were supplemented with dietary JPSP for four weeks (5%, 10%, and 15%, respectively). In addition to attenuating weight gain, JPSP consumption improved dyslipidemia and insulin resistance. In a dose-dependent manner, JPSP consumption ameliorated the expression of hepatic lipogenesis genes (AMPK, SREBP-1, HGMCoA, and ABCG8). The effects on the microbial community structure were determined in all JPSP-supplemented groups; however, the HF-J10 and HF-J15 diets led to a drastic depletion in the species of numerous bacterial families (Bifidobacteriaceae, Mogibacteriaceae, Christensenellaceae, Clostridiaceae, Dehalobacteriaceae, Peptococcaceae, Peptostreptococcaceae, and Ruminococcaceae) compared to the HF diet, some of which represented a reversal of increases associated with HF. The Lachnospiraceae and Enterobacteriaceae families and the Parabacteroides, Sutterella, Allobaculum, and Akkermansia genera were enriched more in the HF-J10 and HF-J15 groups than in the HF group. In conclusion, JPSP consumption improved obesity-related metabolic profiles and had a strong impact on the microbial community structure, thereby reversing NAFLD and decreasing its severity.

Review article: non-alcoholic fatty liver disease and cardiovascular diseases: associations and treatment considerations

BACKGROUND

There are increasing data on the association between non-alcoholic fatty liver disease (NAFLD) and cardiovascular diseases (CVD).

AIM

To summarise evidence on the association between NAFLD and CVD in the clinical setting and provide potential therapeutic implications.

METHODS

We searched PubMed. Evidence was primarily derived from meta-analyses. and then, if data were insufficient, from clinical trials, and then from observational studies.

RESULTS

NAFLD has been linked to arterial hypertension, arterial stiffness, atherosclerosis, coronary artery disease, atrial fibrillation and aortic valvular sclerosis. Advanced liver fibrosis is a crucial prognostic factor for end-stage liver disease and for cardiovascular and overall mortality. Weight loss through lifestyle modifications (diet and exercise) remains the cornerstone of the management of both NAFLD and CVD, but is difficult to achieve and possibly more difficult to sustain long term. Therefore, pharmacological management of NAFLD seems to be important, although no licenced medication currently exists. Pioglitazone, proposed for non-alcoholic steatohepatitis (NASH) by most guidelines, increases weight and should be avoided in congestive heart failure. Statins should not be avoided in NAFLD patients at risk for CVD. Glucagon-like peptide 1 receptor agonists and sodium-glucose cotransporter-2 inhibitors, two classes of anti-diabetic drugs, have shown promising results in NAFLD and CVD, but more studies with hard end points are needed. Obeticholic acid, a promising medication for NASH under investigation, should be carefully considered, owing to its adverse effect on lipid profile.

CONCLUSIONS

NAFLD is associated with CVD, which may have certain clinical and therapeutic implications.

Impact of protocatechuic acid on high fat diet-induced metabolic syndrome sequelae in rats

The study aimed to assess the possible protective impact of protocatechuic acid (PCA) on high fat diet (HFD)-induced metabolic syndrome (Mets) sequelae in rats. Forty-two male Sprague-Dawley (SD) rats were randomly grouped as follows: CTR group; PCA group; HFD group; HFD-PCA group and HFD-MET group. Rats were fed on standard diet or HFD for 14 weeks. HFD-fed rats exhibited significant decreases in food intake and adiponectin (ADP) level; yet, body weight and anthropometrical parameters were significantly increased. Moreover, insulin sensitivity was impaired as indicated by significant elevation in glucose AUC during oral glucose tolerance test (OGTT), fasting serum glucose, fasting serum insulin and homeostasis model assessment of insulin resistance (HOMA-IR) index. Furthermore, chronic HFD feeding elicited significant increases in serum lipid profile and free fatty acids (FFAs) with concomitant hepatic steatosis. Additionally, serum C-reactive protein (CRP), interleukin 1b (Il-1b) and monocyte chemoattractant protein 1(MCP-1) levels were increased. Also, HFD-fed rats exhibited an increase in MDA level, while superoxide dismutase (SOD) and glutathione (GSH) activities were decreased. Moreover, the insulin-signaling pathway was markedly impaired in soleus muscles as indicated by a decrease in insulin-induced AKT phosphorylation. Histopathologically, adipose tissues showed significant increase in adipocyte size. Also, flow cytometry analysis of adipose tissue confirmed a significant increase in the percentage of number of CD68+ cells. PCA administration succeeded to attenuate HFD-induced obesity, insulin resistance, oxidative stress and inflammation. In conclusion, PCA administration could protect against HFD-induced Mets, possibly via its hypoglycemic, insulin-sensitizing, anti-oxidant and anti-inflammatory effects.

Current innovations in nutraceuticals and functional foods for intervention of non-alcoholic fatty liver disease

As innovations in global agricultural production and food trading systems lead to major dietary shifts, high morbidity rates from non-alcoholic fatty liver disease (NAFLD), accompanied by elevated risk of lipid metabolism-related complications, has emerged as a growing problem worldwide. Treatment and prevention of NAFLD and chronic liver disease depends on the availability of safe, effective, and diverse therapeutic agents, the development of which is urgently needed. Supported by a growing body of evidence, considerable attention is now focused on interventional approaches that combines nutraceuticals and functional foods. In this review, we summarize the pathological progression of NAFLD and discuss the beneficial effects of nutraceuticals and the active ingredients in functional foods. We also describe the underlying mechanisms of these compounds in the intervention of NAFLD, including their effects on regulation of lipid homeostasis, activation of signaling pathways, and their role in gut microbial community dynamics and the gut-liver axis. In order to identify novel targets for treatment of lipid metabolism-related diseases, this work broadly explores the molecular mechanism linking nutraceuticals and functional foods, host physiology, and gut microbiota. Additionally, the limitations in existing knowledge and promising research areas for development of active interventions and treatments against NAFLD are discussed.

The preventive effect of liraglutide on the lipotoxic liver injury via increasing autophagy

INTRODUCTION AND OBJECTIVES

The incidence of non-alcoholic fatty liver disease (NAFLD) is increasing. Previous studies indicated that Liraglutide, glucagon-like peptide-1 analogue, could regulate glucose homeostasis as a valuable treatment for Type 2 Diabetes. However, the precise effect of Liraglutide on NAFLD model in rats and the mechanism remains unknown. In this study, we investigated the molecular mechanism by which Liraglutide ameliorates hepatic steatosis in a high-fat diet (HFD)-induced rat model of NAFLD in vivo and in vitro.

MATERIALS AND METHODS

NALFD rat models and hepatocyte steatosis in HepG2 cells were induced by HFD and palmitate fatty acid treatment, respectively. AMPK inhibitor, Compound C was added in HepG2 cells. Autophagy-related proteins LC3, Beclin1 and Atg7, and AMPK pathway-associated proteins were evaluated by Western blot and RT-PCR.

RESULTS

Liraglutide enhanced autophagy as showed by the increased expression of the autophagy markers LC3, Beclin1 and Atg7 in HFD rats and HepG2 cells treated with palmitate fatty acid. In vitro, The AMPK inhibitor exhibited an inhibitory effect on Liraglutide-induced autophagy enhancement with the deceased expression of LC3, Beclin1 and Atg7. Additionally, Liraglutide treatment elevated AMPK levels and TSC1, decreased p-mTOR expression.

CONCLUSIONS

Liraglutide could upregulate autophagy to decrease lipid over-accumulation via the AMPK/mTOR pathway.

Seroprevalence of Helicobacter pylori and its association with metabolic syndrome in a rural community of Bangladesh

BACKGROUND AND AIM

As the interrelationship between Helicobacter pylori, metabolic syndrome (MetS), and non-alcoholic fatty liver disease (NAFLD) is controversial, we undertook a community-based study with the aim to find the seroprevalence of H. pylori and its relationship with MetS and NAFLD.

METHODS

This door-to-door survey was conducted among the adult subjects (≥18 years) of two villages (Charcharia of Dhaka district and Kharrah of Munshiganj district) of Bangladesh. Interviews using a structured questionnaire, clinical examination, anthropometric measurements, ultrasonogram of the liver, and biochemical tests were performed.

RESULTS

Of 1021 subjects, 781 responded (76.49%), and 767 were included in the final analysis (mean age 40.35 ± 15.56 years; female 63.5%). Anti-H. pylori antibodies were found in 418 of 767 (54.5%). There were no H. pylori serostatus association with MetS and diabetes mellitus (DM) in univariate or multivariate analysis (all P > 0.05). However, H. pylori seropositive subjects had lower systolic blood pressure (odds ratio [OR] = -2.95 [-5.58, -0.32]) and low density lipoprotein -cholesterol (OR -7.79 [-15, -0.57]) compared to seronegative subjects in the linear regression model. Seronegativity of H. pylori was associated with NALFD in univariate (P = 0.007) but not multivariate analysis (P = 0.086). There were no differences in the frequency of H. pylori seropositivity among the participants with nonobese compared to obese NAFLD (19/42 [45%] vs 43/99 [43.4%], P = 0.844).

CONCLUSION

In a rural community of Bangladesh, about 55% of the population were H. pylori seropositive, which was more common among the underweight than normal or obese subjects. However, there was no relationship observed between H. pylori seroprevalence and MetS, DM, or NAFLD.

Epidemiology, Pathogenesis, Diagnosis and Emerging Treatment of Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, with an estimated rising prevalence, in concert with the epidemics of obesity and type 2 diabetes. The pathogenesis of NAFLD is not fully elucidated. Besides weight gain and insulin resistance, many other factors seem to contribute, including adipokines, gut microbiota and genetic predisposition. The disease starts as hepatic steatosis, which may proceed to nonalcoholic steatohepatitis (NASH); if fibrosis is added, the risk of cirrhosis and/or hepatocellular carcinoma is augmented. Liver biopsy is considered the gold standard for the diagnosis and staging of NAFLD; the early use of reliable and easily applied diagnostic tools, such as noninvasive biomarkers, is needed to identify patients at different-preferably early-stages of disease however. Whilst lifestyle modification is the first step to manage NAFLD, there is poor compliance, leading to the need of drug therapy. Accordingly, a variety of medications is under investigation. Given the multifaceted pathophysiology of NAFLD, probably, a combination of approaches in an individualized basis may be a more appropriate management. This review summarizes evidence on the epidemiology, pathogenesis, diagnosis and treatment of NAFLD.

Treatment of nonalcoholic fatty liver disease with an anti-osteoporotic medication: A hypothesis on drug repurposing

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a disease of high prevalence without any approved treatment. Nonalcoholic steatohepatitis (NASH) is an advanced phenotype of the disease and the main focus of ongoing clinical trials. Denosumab, a human monoclonal antibody, which binds and inhibits the receptor activator of nuclear factor kappa-B ligand (RANKL), is a licensed medication for postmenopausal, male and glucocorticoid-induced osteoporosis, as well as for metastatic bone disease associated with specific cancers. Hepatic RANKL upregulation has been shown in a transgenic mice model.

HYPOTHESIS

We hypothesized that hepatic RANKL upregulation may be associated with hepatic steatosis and inflammation, thus playing a role in the pathogenesis of NAFLD.

CONCLUSION

If this hypothesis is verified, denosumab, an established anti-osteoporotic medication, may be considered as a candidate for NASH in drug-repurposing studies.

Comparative effectiveness of glucagon-like peptide-1 receptor agonists versus dipeptidyl peptidase-4 inhibitors on noninvasive indices of hepatic steatosis and fibrosis in patients with type 2 diabetes mellitus

BACKGROUND AND AIMS

Nonalcoholic fatty liver disease (NAFLD) is highly prevalent in patients with type 2 diabetes mellitus (T2DM). There is currently no approved treatment for NAFLD. The main aim was the evaluation of the effect of glucagon-like peptide-1 receptor agonists (GLP-1 RA) vs. dipeptidyl peptidase-4 inhibitor (DPP-4i) treatment on noninvasive indices of hepatic steatosis and fibrosis in patients with T2DM.

METHODS

In this retrospective study, three noninvasive indices of hepatic steatosis [HSI, NAFLD ridge score, and triglycerides (TG) to high-density lipoprotein cholesterol (HDL-C) ratio] and five of fibrosis (APRI, FIB-4, NAFLD fibrosis score, BAAT and BARD) were calculated before and after (6-18 months) the addition of a DPP-4i (n = 152) or a GLP-1 RA (n = 37) in patients with T2DM.

RESULTS

Regarding steatosis indices, NAFLD ridge score was significantly decreased in the GLP-1 RA group (baseline: 0.90 ± 0.34, follow-up: 0.67 ± 0.24; p = 0.001), but not in the DPP-4i group (p = 0.25); the difference for group∗time interaction was significant (p = 0.02). HSI showed a trend between groups, being significantly different at baseline and follow-up (p < 0.001) with no significant difference in group∗time interaction. Indices of fibrosis were not essentially changed within or between groups.

CONCLUSIONS

NAFLD ridge score was significantly decreased after the addition of GLP-1 RA in patients with T2DM. This study warrants further prospective clinical trials.

Current and emerging pharmacological options for the treatment of nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is a highly prevalent disease and important unmet medical need. Current guidelines recommend, under specific restrictions, pioglitazone or vitamin E in patients with NASH and significant fibrosis, but the use of both remains off-label. We summarize evidence on medications for the treatment of nonalcoholic steatohepatitis (NASH), since NASH has been mainly associated with higher morbidity and mortality. Some of these medications are currently in phase 3 clinical trials, including obeticholic acid (a farnesoid X receptor agonist), elafibranor (a peroxisome proliferator activated receptor [PPAR]-α/δ dual agonist), cenicriviroc (a CC chemokine receptor antagonist), MSDC-0602 K (a PPAR sparing modulator), selonsertib (an apoptosis signal-regulating kinase-1 inhibitor) and resmetirom (a thyroid hormone receptor agonist). A significant research effort is also targeting PPARs and selective PPAR modulators, including INT131 and pemafibrate, with the expectation that novel drugs may have beneficial effects similar to those of pioglitazone, but without the associated adverse effects. Whether these and other medications could offer tangible therapeutic benefits, alone or in combination, apparently on a background of lifestyle modification, i.e. exercise and a healthy dietary pattern (e.g. Mediterranean diet) remain to be proven. In conclusion, major advances are expected for the treatment of NASH.

Making progress in nonalcoholic fatty liver disease (NAFLD) as we are transitioning from the era of NAFLD to dys-metabolism associated fatty liver disease (DAFLD)

• This is a special issue of “Metabolism” dedicated to nonalcoholic fatty liver disease. • Experts in the field provide an overview of recent progress and developments in NAFLD and offer their expert opinion on future directions. • NAFLD remains a highly prevalent disease without an approved treatment.

The therapeutic potential of C-C chemokine receptor antagonists in nonalcoholic steatohepatitis

Pooled prevalence of nonalcoholic fatty liver disease (NAFLD) globally is about 25%. Nonalcoholic steatohepatitis (NASH) with advanced fibrosis has been linked with substantial morbidity and mortality, without having to-date any licensed treatment. C-C chemokine receptor (CCR) antagonists have been investigated as candidates for the treatment of NASH. Inhibition of CCR2 is expected to mitigate hepatic inflammation, through reducing the activation of Kupffer cells, as well as the infiltration of monocytes and macrophages into the liver. Inhibition of CCR5 is expected to mitigate hepatic fibrogenesis, through impairing the activation of hepatic stellate cells, as well as to mitigate hepatic inflammation, through impairing the activation of Kupffer cells and macrophages. Cenicriviroc (CVC) is the first in class, dual inhibitor of CCR2 and CCR5. After exhibiting favorable results in animal models, CVC was shown to be beneficial in NASH patients with more severe fibrosis at a phase 2b trial (CENTAUR) and is currently at a phase 3 clinical trial (AURORA). Apart from CVC, other CCR5 mono-antagonists, such as maraviroc, are under evaluation in clinical trials with human immunodeficiency virus patients with NAFLD. The aim of this review was to summarize existing evidence on CVC and other CCR antagonists in NASH patients, primarily focusing on their clinical efficacy and safety.

Menopause and Non-Alcoholic Fatty Liver Disease: A Review Focusing on Therapeutic Perspectives

There is increasing evidence that menopause is associated with the progression and severity of non-alcoholic fatty liver disease (NAFLD). Estrogen deficiency worsens non-alcoholic steatohepatitis (NASH) in mice models with fatty liver. The prevalence of NAFLD seems to be higher in postmenopausal compared with premenopausal women. Although more data are needed, lower serum estradiol levels are associated with NASH in postmenopausal women. Apart from estrogen deficiency, relative androgen excess and decrease in sex hormone-binding protein are observed in postmenopausal women. These hormonal changes seem to interplay with an increase in abdominal adipose mass, also observed in postmenopausal women, and aging, which are both closely related to the severity and progressive forms of NAFLD. NAFLD adds extra morbidity to postmenopausal women, possibly increasing the risk of type 2 diabetes mellitus and cardiovascular disease. Improving parameters of the metabolic syndrome via modifications in diet and physical exercise may reduce the risk of NAFLD and its related morbidity. Limited studies have shown a beneficial effect of hormone replacement therapy (HRT) on NAFLD, although adverse hepatic effects have been attributed to progesterone in one study. Phytoestrogens may be alternatives to HRT, but their long-term efficacy and safety remain to be shown. The aim of this review was to summarize evidence linking menopause with NAFLD with a special focus on potential therapeutic perspectives.

Implications of hydrogen sulfide in liver pathophysiology: Mechanistic insights and therapeutic potential

Background

Over the last several decades, hydrogen sulfide (H₂S) has been found to exert multiple physiological functions in mammal systems. The endogenous production of H₂S is primarily mediated by cystathione β-synthase (CBS), cystathione γ-lyase (CSE), and 3-mercaptopyruvate sulfurtransferase (3-MST). These enzymes are widely expressed in the liver tissues and regulate hepatic functions by acting on various molecular targets.

Aim of Review

In the present review, we will highlight the recent advancements in the cellular events triggered by H₂S under liver diseases. The therapeutic effects of H₂S donors on hepatic diseases will also be discussed.

Key Scientific Concepts of Review

As a critical regulator of liver functions, H₂S is critically involved in the etiology of various liver disorders, such as nonalcoholic steatohepatitis (NASH), hepatic fibrosis, hepatic ischemia/reperfusion (IR) injury, and liver cancer. Targeting H₂S-producing enzymes may be a promising strategy for managing hepatic disorders.

Selenium and selenoprotein P in nonalcoholic fatty liver disease

Conflicting data link nonalcoholic fatty liver disease (NAFLD), a disease with no currently approved treatment, with selenium (Se) and selenoprotein P (SELENOP), a glycoprotein synthesized and primarily secreted by the hepatocytes, functioning as a Se transporter from the liver to other tissues. This review aims to summarize the evidence between Se, SELENOP, and NAFLD, which may hopefully clarify whether current data on Se and SELENOP in NAFLD warrant further investigation for their diagnostic and therapeutic potential. Most, albeit not all, experimental data show a favorable effect of Se on hepatic steatosis, inflammation, and fibrosis. It seems that Se may exert an antioxidant effect on the liver, at least partly via increasing the activity of glutathione peroxidase, whose depletion contributes to the pathogenesis of hepatic inflammation and fibrosis. Se may also affect metalloproteinases, cytokines, and growth factors participating in the pathogenesis of NAFLD and, most importantly, may induce the apoptosis of hepatic stellate cells, the key players in hepatic fibrosis. However, the association between Se or SELENOP and insulin resistance, which is a principal pathogenetic factor of NAFLD, remains inconclusive. Clinical studies on Se or SELENOP in NAFLD are conflicting, apart from those in advanced liver disease (cirrhosis or hepatocellular carcinoma), in which lower circulating Se and SELENOP are constant findings. Existing data warrant further mechanistic studies in valid animal models of human NAFLD. Prospective cohort studies and possibly randomized controlled trials are also needed to elucidate the diagnostic and therapeutic potential of Se supplementation in selected NAFLD individuals with Se deficiency.

Farnesoid X nuclear receptor agonists for the treatment of nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) affects 20-40% of the general population. Despite significant disease burden and mortality associated with advanced disease, i.e., nonalcoholic steatohepatitis (NASH), there is currently no approved medication for NASH. Farnesoid X receptor agonists have been investigated as candidates for the treatment of NASH. Obeticholic acid, approved for the treatment of primary biliary cholangitis, has gained significant attention after showing promising results in patients with NASH and fibrosis. Three trials investigating the effect of obeticholic acid in patients with NASH have been completed and the preliminary results of an ongoing one have also been made public. Generally, treatment with obeticholic acid improved hepatic histology, including inflammation and fibrosis, the latter being the main histological predictor of advanced disease. Nonetheless, there were adverse effects, the most common being pruritus and unfavorable changes in the lipid profile. Pruritus led to discontinuation of treatment in some patients. Obeticholic acid, however, is not the only farnesoid X receptor agonist currently investigated for the treatment of NASH. Another farnesoid X receptor agonist, cilofexor, in combination with firsocostat, an acetyl-CoA carboxylase inhibitor, improved hepatic steatosis, liver stiffness, liver function tests and serum fibrosis markers, without causing pruritus after 12 weeks of treatment. In conclusion, current evidence regarding the effect of farnesoid X receptor agonists on hepatic histology in patients with NASH is promising, but several safety issues need further evaluation.

The effect of total anthocyanin-base standardized (Cornus mas L.) fruit extract on liver function, tumor necrosis factor α, malondealdehyde, and adiponectin in patients with non-alcoholic fatty liver: a study protocol for a double-blind randomized clinical trial

Background

Nonalcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases worldwide. Evidence showed that anthocyanins might have effects on NAFLD. Protective effects of Cornelian cherry (Cornus mas L.) extract, as an anthocyanins-rich source, on liver were reported in animal studies. However, very few clinical trials were conducted in this regard. Thus, the aim of this research will be to evaluate the effect of supplementation with total anthocyanin-base standardized cornelian cherry fruit extract on liver function (Serum levels of Alanine aminotransferase (ALT), Aspartate aminotransferase (AST), cytokeratin-18 fragment M30 (CK-18 M30), as well as steatosis and fibrosis of liver), tumor necrosis factor α (TNF-α), malondealdehyde (MDA), and adiponectin in patients with NAFLD.

Methods

In a double-blind randomized clinical trial, 80 NAFLD patients will be studied. The patients will be randomly assigned into two groups. The intervention group will receive the cornelian cherry extract, containing 320 mg.d^− 1 anthocyanins, per day for 12 weeks. The control group will also take the placebo daily for 12 weeks. Liver function (Serum levels of AST, ALT and CK-18 M30; steatosis and fibrosis of liver), serum levels of TNF-α, MDA, and adiponectin will be measured at the baseline and the end of trial for both groups and their results will be compared.

Discussion

Considering evidences about the useful impacts of anthocyanins on NAFLD, the effects of supplementation with cornelian cherry extract will be investigated on the important variables related to NAFLD.

Trial registration

Iranian Registry of Clinical Trials (IRCT20180419039359N1).

Fatty liver in lipodystrophy: A review with a focus on therapeutic perspectives of adiponectin and/or leptin replacement

Lipodystrophy is a group of clinically heterogeneous, inherited or acquired, disorders characterized by complete or partial absence of subcutaneous adipose tissue that may occur simultaneously with the pathological, ectopic, accumulation of fat in other regions of the body, including the liver. Fatty liver adds significantly to hepatic and extra-hepatic morbidity in patients with lipodystrophy. Lipodystrophy is strongly associated with severe insulin resistance and related comorbidities, such as hyperglycemia, hyperlipidemia and nonalcoholic fatty liver disease (NAFLD), but other hepatic diseases may co-exist in some types of lipodystrophy, including autoimmune hepatitis in acquired lipodystrophies, or viral hepatitis in human immunodeficiency virus (HIV)-associated lipodystrophy. The aim of this review is to summarize evidence linking lipodystrophy with hepatic disease and to provide a special focus on potential therapeutic perspectives of leptin replacement therapy and adiponectin upregulation in lipodystrophy.

A Simple Index for Nonalcoholic Steatohepatitis-HUFA-Based on Routinely Performed Blood Tests

Background and objectives: Data suggests that nearly 30% of the general population have steatosis and up to 5% of this population develops nonalcoholic steatohepatitis (NASH). Liver biopsy is still considered to be the gold standard for the diagnosis of NASH. Great effort is being made toward the identification of sensitive diagnostic tests that do not involve invasive procedures to address a common concern in patients with the nonalcoholic fatty liver disease—whether they have NASH or simple steatosis. We aimed to investigate the independent predictors and develop a non-invasive, easy-to-perform, low-cost set of parameters that may be used in clinical practice to differentiate simple steatosis from NASH. Methods: А cross-sectional study of nonalcoholic fatty liver disease (NAFLD) patients divided into two groups: group I—simple steatosis (SS) and group II—biopsy-proven NASH. Strict inclusion criteria and stepwise analysis allowed the evaluation of a vast number of measured/estimated parameters. Results: One hundred and eleven patients were included—82 with simple steatosis and 29 with biopsy-proven NASH. The probability of NASH was the highest when homeostatic model assessment of insulin resistance (HOMA-IR) was above 2.5, uric acid above 380 µmol/L, ferritin above 100 µg/L and ALT above 45 U/L. An acronym of using first letters was created and named the HUFA index. This combined model resulted in an area under the receiver operator characteristic curve (AUROC) of 0.94, provided sensitivity, specificity, positive predictive value and a negative predictive value for NASH of 70.3%, 95.1%, 83.1% and 90.0%, respectively. Conclusion: We suggest a simple non-invasive predictive index HUFA that encompasses four easily available parameters (HOMA-IR, uric acid, ferritin and ALT) to identify patients with NASH, which may reduce the need for a liver biopsy on a routine basis in patients with NAFLD.

Obesity and nonalcoholic fatty liver disease: From pathophysiology to therapeutics

The obesity epidemic is closely associated with the rising prevalence and severity of nonalcoholic fatty liver disease (NAFLD): obesity has been linked not only with simple steatosis (SS), but also with advanced disease, i.e., nonalcoholic steatohepatitis (NASH), NASH-related cirrhosis and hepatocellular carcinoma. As a consequence, apart from increasing all-cause mortality, obesity seems to increase liver-specific mortality in NAFLD patients. Given the lack of approved pharmacological interventions for NAFLD, targeting obesity is a rational option for its management. As the first step, lifestyle modification (diet and exercise) is recommended, although it is difficult to achieve and sustain. When the first step fails, adding pharmacotherapy is recommended. Several anti-obesity medications have been investigated in NAFLD (e.g., orlistat, glucagon-like peptide-1 analogs), other anti-obesity medications have not been investigated (e.g., lorcaserin, phentermine hydrochloric, phentermine/topiramate and naltrexone/bupropion), whereas some medications with weight-lowering efficacy have not been approved for obesity (e.g., sodium-glucose cotransporter-2 inhibitors, farnesoid X receptor ligands). If the combination of lifestyle modification and pharmacotherapy also fails, then bariatric surgery should be considered in selected morbidly obese individuals. This review summarizes best evidence linking obesity with NAFLD and presents related therapeutic options.