Reduction of Hepatic Steatosis, Oxidative Stress, Inflammation, Ballooning and Insulin Resistance After Therapy with Safranal in NAFLD Animal Model: A New Approach

Anti-obesity effects and underlying molecular mechanisms of the ethanolic extract of figs from Ficus hispida using high fat-fed wister rats

Obesity is a known risk factor for many chronic diseases and a substantial threat to public health. We investigated the effects of figs sourced from Ficus hispida on a high fat-fed experimental rat model. We found that a 500-mg dose of ethanolic extract of figs (EFH) reduced oxidative stress markers nitric oxide (NO), malondialdehyde (MDA), and advanced oxidation protein products (AOPP), which were increased in high fat-fed rats. Antioxidant enzymes superoxide dismutase (SOD), catalase, reduced glutathione (GSH), and myeloperoxidase (MPO), found elevated in high fat-fed rats, were also normalized to nearly regular levels by fig treatment. Administration of EFH further reduced fat deposition and expression of adipogenic genes leptin, fatty acid synthase (FAS), peroxisome proliferator-activated receptor gamma (PPARγ), and sterol regulatory element-binding protein-1c (SERBP-1c). Our results suggest that figs have significant effects on reducing oxidative stress and mitigating obesity-associated liver and adipose tissue abnormalities via suppressing adipogenesis. Thus, we propose that F. hispida has potential benefits in reducing obesity.

Exploration of the Key Genes Involved in Non-alcoholic Fatty Liver Disease and Possible MicroRNA Therapeutic Targets

Background

MicroRNAs (miRNAs) are promising therapeutic agents for non-alcoholic fatty liver disease (NAFLD). This study aimed to identify key genes/proteins involved in NAFLD pathogenesis and progression and to evaluate miRNAs influencing their expression.

Methods

Gene expression profiles from datasets GSE151158, GSE163211, GSE135251, GSE167523, GSE46300, and online databases were analyzed to identify significant NAFLD-related genes. Then, protein-protein interaction networks and module analysis identified hub genes/proteins, which were validated using real-time PCR in oleic acid-treated HepG2 cells. Functional enrichment analysis evaluated signaling pathways and biological processes. Gene-miRNA interaction networks identified miRNAs targeting critical NAFLD genes.

Results

The most critical overexpressed hub genes/proteins included: TNF, VEGFA, TLR4, CYP2E1, ACE, SCD, FASN, SREBF2, and TGFB1 based on PPI network analysis, of which TNF, TLR4, SCD, FASN, SREBF2, and TGFB1 were up-regulated in oleic acid-treated HepG2 cells. Functional enrichment analysis for biological processes highlighted programmed necrotic cell death, lipid metabolic process response to reactive oxygen species, and inflammation. In the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, the highest adjusted P-value signaling pathways encompassed AGE-RAGE in diabetic complications, TNF, and HIF-1 signaling pathways. In gene-miRNA network analysis, miR-16 and miR-124 were highlighted as the miRNAs exerting the most influence on important NAFLD-related genes.

Conclusion

In silico analyses identified NAFLD therapeutic targets and miRNA candidates to guide further experimental investigation.

Association of the triglyceride-glucose index variability with blood pressure and hypertension: a cohort study

BACKGROUND

Several studies have indicated that the triglyceride-glucose index (TyG) index is associated with hypertension; however, evidence on the association of change in the TyG index with blood pressure and hypertension is limited.

AIMS

To assess the association of the TyG index with blood pressure and hypertension.

DESIGN

A cohort study.

METHODS

We included 17 977 individuals with a mean age of 60.5 years from the Dongfeng-Tongji cohort. The TyG index was calculated as ln [fasting triglyceride (mg/dl)×fasting glucose (mg/dl)/2]. Hypertension was defined as blood pressure ≥140/90 mmHg, self-reported current use of antihypertensive medication or self-reported physician diagnosis of hypertension.

RESULTS

In the longitudinal analyses, we found a linear dose-response relationship between changes in the TyG index and change in blood pressure. Each one-unit change in the TyG index was associated with a 1.93 (1.23-2.63) mmHg increase in systolic blood pressure (SBP) and a 1.78 (1.42-2.16) mmHg increase in diastolic blood pressure (DBP). During a median follow-up of 9.37 years, a total of 3594 individuals were newly diagnosed with hypertension. We also found a linear dose-response relationship between the TyG index and the incidence of hypertension. The hazard ratio (HR) of hypertension for each one-unit increase in the TyG index was 1.21 (1.13-1.29). In addition, the best cut-off point of TyG for predicting hypertension was 8.4797, with sensitivity, and specificity of 57.85% and 55.40%, respectively.

CONCLUSIONS

The TyG index had a positive dose-response relationship with blood pressure and could be used to predict the risk of hypertension.

Effects of carnosine supplementation on markers for the pathophysiological development of metabolic dysfunction-associated steatotic liver disease in a diet-induced model

Consumption of diets high in sugar and fat is related to the development of Metabolic dysfunction-associated steatotic liver disease (MASLD). Carnosine (CAR) is a dipeptide with antioxidant and anti-inflammatory action and has been studied for treating diseases. This work aimed to evaluate the effects of CAR on diet-induced MASLD in rats. Male Wistar rats were distributed into 2 groups (17 weeks): normocaloric (Co, n = 12), and hypercaloric diet rich in lipids and simple carbohydrates (MASLD, n = 12). After, the animals were redistributed to begin the treatment with CAR (4 weeks): Co (n = 6), Co + CAR (n = 6), MASLD (n = 6), and MASLD + CAR (n = 6), administered intraperitoneally (250 mg/kg). Evaluations included nutritional, hormonal and metabolic parameters; hepatic steatosis, inflammatory and oxidative markers. MASLD group had a higher adiposity index, systolic blood pressure, glucose, plasma and liver triglycerides and cholesterol, insulin, hepatic steatosis, oxidative markers, and lower PPAR-α (Peroxisome Proliferator-activated receptor α), compared to the Co. CAR attenuated plasma and hepatic triglyceride and cholesterol levels, hepatic steatosis, CD68+ macrophages, and hepatic oxidative markers, in addition to increasing HDL cholesterol levels and PPAR-α, compared to the untreated MASLD group. CAR acts in importants pathophysiological processes of MASLD and may be a therapeutic compound to control the disease.

The Effects of Chia Defatted Flour as a Nutritional Supplement in C57BL/6 Mice Fed a Low-Quality Diet

Today, consumption of diets rich in saturated fat and fructose, associated with a variety of metabolic deregulations, has increased. The aim of this study was to evaluate the effect of dietary supplementation with a residue of defatted chia seed on a diet with low nutritional quality. To do this, C57BL/6 male mice were fed with the Control (C), Low-Nutritional-Quality (LNQ), or supplemented-with-chia-defatted-flour (LNQ+C) diets. After 12 weeks, the glucose and lactate levels were determined in the serum, liver, and kidney, along with reactive oxygen species (ROS) levels, antioxidant enzyme activity, reduced glutathione (GSH), and protein oxidation (AOPP). The LNQ diet increased the glucose and lactate levels (+25% and +50% approx. in the liver, with respect to the control group) and generated oxidative stress by modifying the levels of ROS and the activity of antioxidant enzymes, causing oxidative damage to proteins (+12% in the liver, with respect to the control). Chia supplementation helped to restore the glucose to control levels and modulate the endogenous antioxidant system, resulting in a decrease in protein oxidation products with no differences compared to the control group. In conclusion, supplementation with chia showed beneficial effects on the general health of mice, even when fed a low-nutritional-quality diet.

Galectin-3 and Severity of Liver Fibrosis in Metabolic Dysfunction-Associated Fatty Liver Disease

Metabolic dysfunction-associated Fatty Liver Disease (MAFLD) is a chronic liver disease characterized by the accumulation of fat in the liver and hepatic steatosis, which can progress to critical conditions, including Metabolic dysfunction-associated Steatohepatitis (MASH), liver fibrosis, hepatic cirrhosis, and hepatocellular carcinoma. Galectin-3, a member of the galectin family of proteins, has been involved in cascades that are responsible for the pathogenesis and progression of liver fibrosis in MAFLD. This review summarizes the present understanding of the role of galectin-3 in the severity of MAFLD and its associated liver fibrosis. The article assesses the underlying role of galectin-3-mediated fibrogenesis, including the triggering of hepatic stellate cells, the regulation of extracellular degradation, and the modulation of immune reactions and responses. It also highlights the assessments of the potential diagnostic and therapeutic implications of galectin-3 in liver fibrosis during MAFLD. Overall, this review provides insights into the multifaceted interaction between galectin-3 and liver fibrosis in MAFLD, which could lead to the development of novel strategies for diagnosis and treatment of this prevalent liver disease.

Extracellular matrix turnover: phytochemicals target and modulate the dual role of matrix metalloproteinases (MMPs) in liver fibrosis

Extracellular matrix (ECM) resolution by matrix metalloproteinases (MMPs) is a well-documented mechanism. MMPs play a dual and complex role in modulating ECM degradation at different stages of liver fibrosis, depending on the timing and levels of their expression. Increased MMP-1 combats disease progression by cleaving the fibrillar ECM. Activated hepatic stellate cells (HSCs) increase expression of MMP-2, -9, and -13 in different chemicals-induced animal models, which may alleviate or worsen disease progression based on animal models and the stage of liver fibrosis. In the early stage, elevated expression of certain MMPs may damage surrounding tissue and activate HSCs, promoting fibrosis progression. At the later stage, downregulation of MMPs can facilitate ECM accumulation and disease progression. A number of phytochemicals modulate MMP activity and ECM turnover, alleviating disease progression. However, the effects of phytochemicals on the expression of different MMPs are variable and may depend on the disease models and stage, and the dosage, timing and duration of phytochemicals used in each study. Here, we review the most recent advances in the role of MMPs in the effects of phytochemicals on liver fibrogenesis, which indicates that further studies are warranted to confirm and define the potential clinical efficacy of these phytochemicals.

Effect of saffron, black seed, and their main constituents on inflammatory cytokine response (mainly TNF-α) and oxidative stress status: an aspect on pharmacological insights

Tumor necrosis factor-α (TNF-α), an inflammatory cytokine, is produced by monocytes and macrophages. It is known as a 'double-edged sword' because it is responsible for advantageous and disadvantageous events in the body system. The unfavorable incident includes inflammation, which induces some diseases such as rheumatoid arthritis, obesity, cancer, and diabetes. Many medicinal plants have been found to prevent inflammation, such as saffron (Crocus sativus L.) and black seed (Nigella sativa). Therefore, the purpose of this review was to assess the pharmacological effects of saffron and black seed on TNF-α and diseases related to its imbalance. Different databases without time limitations were investigated up to 2022, including PubMed, Scopus, Medline, and Web of Science. All the original articles (in vitro, in vivo, and clinical studies) were collected on the effects of black seed and saffron on TNF-α. Black seed and saffron have therapeutic effects against many disorders, such as hepatotoxicity, cancer, ischemia, and non-alcoholic fatty liver, by decreasing TNF-α levels based on their anti-inflammatory, anticancer, and antioxidant properties. Saffron and black seed can treat a variety of diseases by suppressing TNF-α and exhibiting a variety of activities such as neuroprotective, gastroprotective, immunomodulatory, antimicrobial, analgesic, antitussive, bronchodilator, antidiabetic activity, anticancer, and antioxidant effects. To uncover the beneficial underlying mechanisms of black seed and saffron, more clinical trials and phytochemical research are required. Also, these two plants affect other inflammatory cytokines, hormones, and enzymes, implying that they could be used to treat a variety of diseases.

Coagulation Dysfunctions in Non-Alcoholic Fatty Liver Disease-Oxidative Stress and Inflammation Relevance

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases. Its incidence is progressively rising and it is possibly becoming a worldwide epidemic. NAFLD encompasses a spectrum of diseases accounting for the chronic accumulation of fat within the hepatocytes due to various causes, excluding excessive alcohol consumption. In this study, we aimed to focus on finding evidence regarding the implications of oxidative stress and inflammatory processes that form the multifaceted pathophysiological tableau in relation to thrombotic events that co-occur in NAFLD and associated chronic liver diseases. Recent evidence on the pathophysiology of NAFLD suggests that a complex pattern of multidirectional components, such as prooxidative, proinflammatory, and prothrombotic components, better explains the multiple factors that promote the mechanisms underlying the fatty acid excess and subsequent processes. As there is extensive evidence on the multi-component nature of NAFLD pathophysiology, further studies could address the complex interactions that underlie the development and progression of the disease. Therefore, this study aimed to describe possible pathophysiological mechanisms connecting the molecular impairments with the various clinical manifestations, focusing especially on the interactions among oxidative stress, inflammation, and coagulation dysfunctions. Thus, we described the possible bidirectional modulation among coagulation homeostasis, oxidative stress, and inflammation that occurs in the various stages of NAFLD.

HBx induced upregulation of FATP2 promotes the development of hepatic lipid accumulation

The hepatitis B Virus X (HBx) protein plays a crucial role in the HBV-induced hepatic steatosis. Fatty acid transport protein 2 (FATP2) is a key protein that is involved in hepatic lipogenesis, and it was found to be highly expressed in various metabolic diseases. However, Whether FATP2 is a key factor in the pathogenesis of HBx-induced hepatic steatosis remains unclear. In this study, we found that FATP2 was up-regulated by HBx in vitro and in vivo and participated in HBx-induced hepatic lipid accumulation. Treatment of HBx-expressing cell lines and mice with FATP2 inhibitor (FATP2i) lipofermata ameliorated HBx-induced lipid accumulation and reduced oxidative stress and inflammation caused by lipid accumulation. Moreover, the liver injury of mouse was restored after FATP2i treatment. In summary, our results reveal that FATP2 is a key driver factor for HBx-induced hepatic lipid accumulation, and inhibition of FATP2 can ameliorates lipid accumulation caused by HBx. This study provides new insights into the mechanism of HBV-induced hepatic steatosis.

Utility of Human Relevant Preclinical Animal Models in Navigating NAFLD to MAFLD Paradigm

Fatty liver disease is an emerging contributor to disease burden worldwide. The past decades of work established the heterogeneous nature of non-alcoholic fatty liver disease (NAFLD) etiology and systemic contributions to the pathogenesis of the disease. This called for the proposal of a redefinition in 2020 to that of metabolic dysfunction-associated fatty liver disease (MAFLD) to better reflect the current understanding of the disease. To date, several clinical cohort studies comparing NAFLD and MAFLD hint at the relevancy of the new nomenclature in enriching for patients with more severe hepatic injury and extrahepatic comorbidities. However, the underlying systemic pathogenesis is still not fully understood. Preclinical animal models have been imperative in elucidating key biological mechanisms in various contexts, including intrahepatic disease progression, interorgan crosstalk and systemic dysregulation. Furthermore, they are integral in developing novel therapeutics against MAFLD. However, substantial contextual variabilities exist across different models due to the lack of standardization in several aspects. As such, it is crucial to understand the strengths and weaknesses of existing models to better align them to the human condition. In this review, we consolidate the implications arising from the change in nomenclature and summarize MAFLD pathogenesis. Subsequently, we provide an updated evaluation of existing MAFLD preclinical models in alignment with the new definitions and perspectives to improve their translational relevance.

Luteolin loaded on zinc oxide nanoparticles ameliorates non-alcoholic fatty liver disease associated with insulin resistance in diabetic rats via regulation of PI3K/AKT/FoxO1 pathway

OBJECTIVE

Non-alcoholic fatty liver disease (NAFLD) is a worldwide health problem with high prevalence and morbidity associated with obesity, insulin resistance, type 2 diabetes mellitus (T2DM), and dyslipidemia. Nano-formulation of luteolin with Zn oxide in the form of Lut/ZnO NPs may improve the anti-diabetic property of each alone and ameliorate the insulin resistance thus management of NAFLD. This study aimed to measure the efficiency of Lut/ZnO NPs against insulin resistance coupled with NAFLD and T2DM.

METHODS

A diabetic rat model with NAFLD was induced by a high-fat diet and streptozotocin (30 mg/kg I.P). Serum diabetogenic markers levels, lipid profile, and activity of liver enzymes were measured beside liver oxidative stress markers. Moreover, the hepatic expressions of PI3K/AKT/FoxO1/SERBP1c as well as heme oxygenase-1 were measured beside the histopathological examination.

RESULTS

Lut/ZnO NPs treatment effectively reduced hyperglycemia, hyperinsulinemia, and ameliorated insulin resistance. Additionally, Lut/ZnO NPs improved the hepatic functions, the antioxidant system, and reduced the oxidative stress markers. Furthermore, the lipid load in the liver, as well as the circulating TG and TC, was minified via the suppression of lipogenesis and gluconeogenesis. Moreover, Lut/ZnO NPs activated the PI3K/AKT signaling pathway, hence inactivating FoxO1, therefore enhancing the hepatic cells' insulin sensitivity.

CONCLUSION

Lut/ZnO NPs have a hepatoprotective effect and may relieve the progression of NAFLD by alleviating insulin resistance, ameliorating the antioxidant status, and regulating the insulin signal pathway.

Rho-kinase inhibition ameliorates non-alcoholic fatty liver disease in type 2 diabetic rats

Non-alcoholic fatty liver disease (NAFLD) is linked to type 2 diabetes mellitus (T2DM), obesity, and insulin resistance. The Rho/ROCK pathway had been involved in the pathophysiology of diabetic complications. This study was designed to assess the possible protective impacts of the Rho/Rho-associated coiled-coil containing protein kinase (Rho/ROCK) inhibitor fasudil against NAFLD in T2DM rats trying to elucidate the underlying mechanisms. Animals were assigned into control rats, non-treated diabetic rats with NAFLD, and diabetic rats with NAFLD that received fasudil treatment (10 mg/kg per day) for 6 weeks. The anthropometric measures and biochemical analyses were performed to assess metabolic and liver function changes. The inflammatory and oxidative stress markers and the histopathology of rat liver tissues were also investigated. Groups with T2DM showed increased body weight, serum glucose, and insulin resistance. They exhibited disturbed lipid profile, enhancement of inflammatory cytokines, and deterioration of liver function. Fasudil administration reduced body weight, insulin resistance, and raised liver enzymes. It improved the disturbed lipid profile and attenuated liver inflammation. Moreover, it slowed down the progression of high fat diet (HFD)-induced liver injury and reduced the caspase-3 expression. The present study demonstrated beneficial amelioration effect of fasudil on NAFLD in T2DM. The mechanisms underlying these impacts are improving dyslipidemia, attenuating oxidative stress, downregulated inflammation, improving mitochondrial architecture, and inhibiting apoptosis.

The obesity and nonalcoholic fatty liver disease mouse model revisited: Liver oxidative stress, hepatocyte apoptosis, and proliferation

The study revisited the diet-induced obesity (DIO) mice and the nonalcoholic fatty liver disease (NAFLD) pathogenesis to serve as a translational model. Hepatic beta-oxidation pathways, lipogenesis, oxidative stress, hepatocyte apoptosis, and proliferation were investigated in obese mice. Three-month-old male mice were divided according to their diet for fifteen weeks, the control diet (C group, containing 10% energy from fat) and the high-fat diet (HF group, containing 50% energy from fat). Body weight (BW), liver mass, and steatosis were higher in the HF group than in the C group. Also, gene expression related to beta-oxidation and lipogenesis showed an adverse profile, and insulin and glucose signaling pathways were impaired in the HF group compared to the C group. As a result, steatosis was prevalent in the HF group but not in the C group. Furthermore, the pathways that generate NAFLD were negatively modulated by oxidative stress in the HF animals than in the C ones. The caspase 3 immunolabeled HF hepatocytes with increased gene and protein expressions related to apoptosis while proliferating cell nuclear antigen labeled C hepatocytes. In conclusion, the findings in the DIO mouse model reproduce the NAFLD profile relative to the human NAFLD's apoptosis, insulin signaling, lipogenesis, beta-oxidation, and oxidative stress. Therefore, the model is adequate for a translational perspective's morphological, biochemical, and molecular research on NAFLD.

Downregulation of hepatic fat accumulation, inflammation and fibrosis by nerolidol in purpose built western-diet-induced multiple-hit pathogenesis of NASH animal model

Western diet style (fast food), which includes fatty frozen junk food, lard, processed meats, whole-fat dairy foods, cream, mayonnaise, butter, snacks, and fructose, is a primary etiological determinant for developing nonalcoholic steatohepatitis (NASH) worldwide. Here the primary focus is to see the impact of naturally identified essential oil on disease mechanisms developed in an animal model using the same ingredients. Currently, symptomatic therapies are recommended for the management of NASH due to non-availability of specific treatments. Therefore, the present study was designed to evaluate the potential anti-NASH effect of nerolidol in a rat model fed with a purpose-built diet. The diet substantially induced insulin resistance, hepatic steatosis, dyslipidemia, and elevation of liver enzymes in the experimental animals. The levels of liver oxidative stress markers, nitrites (NO₂^-), serum pro-inflammatory cytokine (TNF-α) and hepatic collagen were increased in disease control rats. Nerolidol oral treatment in ascending dose order of 250 and 500 mg/kg substantially reduced the steatosis (macrovesicular and microvesicular), degeneration of hepatocytes, and inflammatory cells infiltration. The amounts of circulatory TNF-α and tissue collagen were also reduced at 500 mg/kg dose of nerolidol, expressing its anti-fibrotic effect. The current study described the multiple-hit pathophysiology of NASH as enhanced steatosis, pro-inflammatory markers, and oxidative stress in rats, which resulted in the development of vicious insulin resistance. Nerolidol treatment significantly reduced hepatic lipid accumulation and halted disease progression induced by a hypercaloric diet.