The Preventive and Therapeutic Potential of the Flavonoids in Liver Cirrhosis: Current and Future Perspectives

Investigating the protective effects of luteolin and gallic acid from Luffa acutangulavar. amara (Roxb.) C. B. Clarke. Fruit pericarp against alcohol-induced liver toxicity: Extraction, bioactivity-guided fractionation, molecular docking, and dynamics studies

ETHNOPHARMACOLOGICAL RELEVANCE

Luffa acutangula var. amara (Roxb.) C.B. Clarke, known as 'Katu Koshataki' in Ayurveda, is a traditional medicinal plant in India. The juice of these fruits is recommended for chronic alcohol-induced liver diseases.

AIM OF THE STUDY

This study aimed to validate the hepatoprotective and antioxidant properties of Luffa acutangula var. amara fruit pericarp ethanolic extract (EOLA) against ethanol-induced chronic hepatotoxicity in rats, isolate bioactive phytochemicals and in silico evaluation.

MATERIALS AND METHODS

Ethanolic extract of L. acutangula var. amara fruit pericarp was evaluated in chronic alcohol-induced hepatitis (20% ethanol orally twice daily for 28 days) at doses of 100 and 200 mg/kg p.o. Additionally, in vivo anti-inflammatory and antioxidant potential were assessed. Luteolin and gallic acid were isolated using bioactivity guided fractionation. Furthermore, these phytochemicals were assessed for hepatoprotective potential using molecular docking and molecular dynamics studies against different targets.

RESULTS

The EOLA demonstrated efficacy in stabilizing elevated biochemical markers and antioxidant levels associated with ethanol-induced hepatotoxicity in rats, and it preserved the normal architecture of hepatocytes in histological analyses compared to the ethanol control group. The EOLA was subjected to fractionation using hexane: chloroform (8:2 → 2:8), followed by chloroform: methanol (8:2 → 2:8) to yield a total eight fractions. The fractions 1, 2, and 3 showed potent antioxidant potential, yielding luteolin and gallic acid as LAC-1 and LAC-3 from fractions 1 and 8, respectively. Gallic acid and luteolin were investigated using molecular docking and molecular dynamic simulation techniques to assess their interactions with key proteins such as Cytochrome P450 2C9, Superoxide Dismutase, Glutathione Peroxidase, Glutathione S-Transferase, Catalase, Peroxisome Proliferator-Activated Receptor-ϒ, Vanin-1, and Cannabinoid Receptor CB2. The metabolites exhibit strong binding stability, with a root mean square deviation range of less than 2.8 Å.

CONCLUSIONS

It can be concluded that the fruit pericarp of L. acutangula var. amara could be used as a functional food for reducing the liver damage caused by alcohol and other factors.

Prevention of fenitrothion induced hepatic toxicity by saponarin via modulating TLR4/MYD88, JAK1/STAT3 and NF-κB signaling pathways

Fenitrothion (FEN) is an organophosphate insecticidal agent that is considered as major source of organs toxicity. Saponarin (SAP) is a naturally occurring novel flavone that exhibits a wide range of medicinal properties. The current trial was conducted to evaluate the ameliorative potential of SAP against FEN instigated liver toxicity in rats. Thirty-two male albino rats were apportioned into four groups including control, FEN (10 mg/kg), FEN (10 mg/kg) + SAP (80 mg/kg), and SAP (80 mg/kg) alone treated group. It was revealed that FEN administration upregulated the gene expression of TNF-α, TLR4, IL-1β, MYD88, IL-6, TRAF6, COX-2, NF-κB, JAK1 and STAT3 while reducing the gene expression of IκB. Moreover, the levels of reactive oxygen species (ROS) and malondialdehyde (MDA) were increased while the activities of catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD), heme-oxygenase-1 (HO-1) and glutathione reductase (GSR) were decreased after FEN exposure. Furthermore, FEN administration notably escalated the levels of hepatic enzymes including alanine transaminase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT) and alkaline phosphatase (ALP) whereas reduced the levels of total proteins and albumin. Besides, FEN intake upregulated the levels of Caspase-9, Bax and Caspase-3 while reducing the levels of Bcl-2. Hepatic histology was impaired after FEN intoxication. Nonetheless, SAP treatment remarkably protected the normal state of liver via regulating abovementioned irregularities. Our in-silico analysis confirmed that SAP hold that potential to interact with binding pocket of these proteins, highlighting its ability as a therapeutic compound to alleviate FEN-induced liver damage.

Swertia cincta and its main active ingredients regulate the PPAR-α pathway in anti-cholestatic liver injury

ETHNOPHARMACOLOGICAL RELEVANCE

Swertia cincta is a traditional remedy for cholestasis commonly utilised in Yunnan, China. Despite its widespread use, the specific active components and underlying mechanisms of action remain poorly understood.

AIM OF THIS STUDY

This study aimed to investigate the therapeutic properties, mechanisms, and active compounds of Swertia cincta in an animal model of cholestasis induced by alpha-naphthylisothiocyanate (ANIT).

MATERIALS AND METHODS

UHPLC/Q-TOF-MS and high-performance liquid chromatography (HPLC) were utilised to analyse the blood components of Swertia cincta. An ANIT-induced cholestatic liver injury animal model was established, and metabolomics was employed to explore the potential mechanisms of Swertia cincta in treating cholestatic liver injury. Hepatocellular injury induced by taurochenodeoxycholic acid was evaluated in vitro, and key bioactive components of Swertia cincta for cholestatic liver injury treatment were identified and confirmed using the ANIT-induced mouse model.

RESULTS

The established HPLC method demonstrates good specificity and reproducibility, enabling the simultaneous determination of six components in Swertia cincta. Results from serum biochemical indicators and liver pathology analysis indicated that Swertia cincta exhibits promising anti-cholestasis liver injury effects. Specifically, gentiopicroside, loganic acid, and isoorientin were identified as key active ingredients in treating cholestatic liver injury. Their mechanism of action primarily involves regulating PPAR-α, FXR, CYP3A4, NTCP, CAR, and CPT2. By modulating PPAR-α and bile acid metabolism-related proteins, reducing pro-inflammatory factors, enhancing bile acid transport, and promoting fatty acid oxidation to reduce lipid accumulation, Swertia cincta exerts protective and therapeutic effects against cholestatic liver injury. Notably, gentian bitter glycosides appear to be the most critical components for this effect.

CONCLUSION

Swertia cincta may improve cholestatic liver injury by activating the peroxisome proliferator-activated receptor alpha pathway, and the key active compounds were gentiopicroside, loganic acid, and isoorientin.

Enhanced anti-inflammatory and anti-fibrotic effects of nanoparticles loaded with a combination of Aloe vera-Moringa oleifera extracts

Metabolic associated steatohepatitis characterized by lipid accumulation, inflammation and fibrosis, is a growing global health issue, contributing to severe liver-related mortality. With limited effective treatments available, there is an urgent need for novel therapeutic strategies. Moringa oleifera, rich in antioxidants, offers potential for combating steatohepatitis, but its cytotoxicity presents challenges. Aloe vera, renowned for its cytocompatibility and anti-inflammatory effects, shows promise in mitigating these risks. Using infrared spectrometry and mass spectrometry, we identified 1586 metabolites from both plants across 84 chemical classes. By encapsulating these phytochemicals in nanoparticles, we achieved increased solubility, cytocompatibility, and gene modulation to hepatic stellate cells affected by steatohepatitis. Chemoinformatic analysis revealed bioactive metabolites, including hesperetin analogs, known to inhibit TGF-β. Our results demonstrate that these nanoparticles not only improved gene expression modulation related to metabolic associated steatohepatitis, particularly TGF-β and COL1A1, but also outperformed free compounds, highlighting their potential as a novel therapeutic approach.

The potential of flavonoids in hepatic fibrosis: A comprehensive review

BACKGROUND

Hepatic fibrosis is a pathophysiological process of extracellular matrix abnormal deposition induced by multiple pathogenic factors. Currently, there is still a lack of effective and non-toxic drugs for treating fibrosis in clinic. Flavonoids are polyphenolic compounds synthesized in plants and modern pharmacological studies confirmed flavonoids exhibit potent hepatoprotective effect.

PURPOSE

Summarize literature to elaborate the mechanism of HF and evaluate the potential of flavonoids in HF, aiming to provide a new perspective for future research.

METHODS

The literatures about hepatic fibrosis and flavonoids are collected via a series of scientific search engines including Google Scholar, Elsevier, PubMed, CNKI, WanFang, SciFinder and Web of Science database. The key words are "flavonoids", "hepatic fibrosis", "pharmacokinetic", "toxicity", "pathogenesis" "traditional Chinese medicine" and "mechanism" as well as combination application.

RESULTS

Phytochemical and pharmacological studies revealed that about 86 natural flavonoids extracted from Chinese herbal medicines possess significantly anti-fibrosis effect and the mechanisms maybe through anti-inflammatory, antioxidant, inhibiting hepatic stellate cells activation and clearing activated hepatic stellate cells.

CONCLUSIONS

This review summarizes the flavonoids which are effective in HF and the mechanisms in vivo and in vitro. However, fewer studies are focused on the pharmacokinetics of flavonoids in HF model and most studies are limited to preclinical studies, therefore there is no reliable data from clinical trials for the development of new drugs. Further in-depth research related it can be conducted to improve the bioavailability of flavonoids and serve the development of new drugs.

Exploring the effectiveness of flavone derivatives for treating liver diseases: Utilizing DFT, molecular docking, and molecular dynamics techniques

In exploring nature's potential in addressing liver-related conditions, this study investigates the therapeutic capabilities of flavonoids. Utilizing in silico methodologies, we focus on flavone and its analogs (1-14) to assess their therapeutic potential in treating liver diseases. Molecular change calculations using density functional theory (DFT) were conducted on these compounds, accompanied by an evaluation of each analog's physiochemical and biochemical properties. The study further assesses these flavonoids' binding effectiveness and locations through molecular docking studies against six target proteins associated with human cancer. Tropoflavin and taxifolin served as reference drugs. The structurally modified flavone analogs (1-14) displayed a broad range of binding affinities, ranging from -7.0 to -9.4 kcal mol⁻¹, surpassing the reference drugs. Notably, flavonoid (7) exhibited significantly higher binding affinities with proteins Nrf2 (PDB:1 × 2 J) and DCK (PDB:1 × 2 J) (-9.4 and -8.1 kcal mol⁻¹) compared to tropoflavin (-9.3 and -8.0 kcal mol⁻¹) and taxifolin (-9.4 and -7.1 kcal mol⁻¹), respectively. Molecular dynamics (MD) simulations revealed that the docked complexes had a root mean square deviation (RMSD) value ranging from 0.05 to 0.2 nm and a root mean square fluctuation (RMSF) value between 0.35 and 1.3 nm during perturbation. The study concludes that 5,7-dihydroxyflavone (7) shows substantial promise as a potential therapeutic agent for liver-related conditions. However, further validation through in vitro and in vivo studies is necessary. Key insights from this study include:•Screening of flavanols and their derivatives to determine pharmacological and bioactive properties using ADMET, molinspiration, and pass prediction analysis.•Docking of shortlisted flavone derivatives with proteins having essential functions.•Analysis of the best protein-flavonoid docked complexes using molecular dynamics simulation to determine the flavonoid's efficiency and stability within a system.

Biological Role and Related Natural Products of SIRT1 in Nonalcoholic Fatty Liver

Non-alcoholic fatty liver disease(NAFLD) is an umbrella term for a range of diseases ranging from hepatic fat accumulation and steatosis to non-alcoholic steatohepatitis (NASH) in the absence of excessive alcohol consumption and other definite liver damage factors. The incidence of NAFLD has increased significantly in recent years and will continue to grow in the coming decades. NAFLD has become a huge health problem and economic burden. SIRT1 is a member of Sirtuins, a group of highly conserved histone deacetylases regulated by NAD+, and plays a vital role in regulating cholesterol and lipid metabolism, improving oxidative stress, inflammation, and insulin resistance through deacetylating some downstream transcription factors and thus improving NAFLD. Although there are no currently approved drugs for treating NAFLD and some unresolved limitations in developing SIRT1 activators, SIRT1 holds promise as a proper therapeutic target for NAFLD and other metabolic diseases. In recent years, natural products have played an increasingly important role in drug development due to their safety and efficacy. It has been discovered that some natural products may be able to prevent and treat NAFLD by targeting SIRT1 and its related pathways. This paper reviews the mechanism of SIRT1 in the improvement of NALFD and the natural products that regulate NAFLD through SIRT1 and its associated pathways, and discusses the potential of SIRT1 as a therapeutic target for treating NAFLD and the effectiveness of these related natural products as clinical drugs or dietary supplements. These works may provide some new ideas and directions for finding new therapeutic targets for NAFLD and the development of anti-NAFLD drugs with good pharmacodynamic properties.

Montelukast prevents mice against carbon tetrachloride- and methionine-choline deficient diet-induced liver fibrosis: Reducing hepatic stellate cell activation and inflammation

AIMS

Montelukast is an antagonist of cysteinyl leukotriene receptor 1 (CysLTR1) that protects against inflammation and oxidative stress. However, the function of montelukast in liver fibrosis remains unknown. In this study, we examined whether the pharmacological inhibition of CysLTR1 could protect mice against hepatic fibrosis.

MATERIALS AND METHODS

Carbon tetrachloride (CCl₄) and methionine-choline deficient (MCD) diet models were used in this study. The expression of CysLTR1 in liver were detected by RT-qPCR and Western blot analysis. Liver hydroxyproline levels, fibrotic genes expression, serum biochemical indexes and inflammatory factors were used to evaluate the effect of montelukast on liver fibrosis, injury, and inflammation. In vitro, we used the RT-qPCR and Western blot analysis to assess CysLTR1 in mouse primary hepatic stellate cell (HSC) and human LX-2 cell line. The role of montelukast on HSC activation and the underlying mechaisms were determined using RT-qPCR analysis, Western blot and immunostaining assays.

KEY FINDINGS

Chronic stimulation from CCl₄ and MCD diet upregulated the mRNA and protein levels of CysLTR1 in the liver. Pharmacological inhibition of CysLTR1 by montelukast ameliorated liver inflammation and fibrosis in both models. Mechanistically, montelukast suppressed HSC activation by targeting the TGFβ/Smad pathway in vitro. The hepatoprotective effect of montelukast was also associated with reduced liver injury and inflammation.

SIGNIFICANCE

Montelukast suppressed CCl₄- and MCD-induced chronic hepatic inflammation and liver fibrosis. CysLTR1 might be a therapeutic target for treating liver fibrosis.