Anti-inflammatory and Antifibrotic Effects of Harpullia cupanioides L. Leaves in Thioacetamide-Induced Liver Fibrosis in Rats

Introduction: Inflammation is mainly caused by cellular and vascular factors. Lymphocytes and macrophages are among the circulating cellular constituents. It is indisputable that macrophages play a part in inflammation. Harpullia cupanioides (Sapindaceae) methanol extract was investigated in vitro against the RAW 264.7 murine macrophage cell line to discover its cytotoxic and anti-inflammatory activities. An in vivo study was conducted to investigate the anti-inflammatory and anti-fibrotic effects of Harpullia cupanioides (HC) in Thioacetamide–induced rats (TAA), through the determination of oxidative stress markers Glutathione (GSH), lipid peroxide (MDA), and Total Antioxidant Capacity (TAC). Additionally, lipid profile, liver function enzyme activities, Gamma-Glutamyl Transferase (GGT), total bilirubin, Tumor Necrosis Factor-α (TNF-α), Interleukin-6 (IL-6), collagen type I, Tumor Growth Factor-β (TGF-β), and Metalloproteinase-9 (MMP-9) were assessed. Material and Methods: This research aimed to investigate the beneficial impact of HC extract in vitro and in vivo in rats induced by TAA, as determined by the measurement of several biomarkers. Fibrosis was triggered through the administration of TAA (200 mg/kg, intraperitoneally) twice a week for a duration of six weeks. The activities of serum transaminases (AST, ALT), inflammatory cytokines, including TNF-α, IL-6, TGF-β, and fibrotic biomarkers (collagen 1V and MMP-9), as well as liver histopathological alterations, were evaluated. results: TAA induced marked histopathological changes in liver tissues coupled with elevations in serum transaminases activities. Furthermore, hepatic content of lipid peroxidation (MDA) and tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), collagen 1V and TGF β were elevated, together with a reduction of metalloproteinase -9 (MMP-9) in the liver. Treatment with Harpullia cupanoide ameliorated liver tissue against TAA-induced liver fibrosis, as proved by the alleviation of inflammatory and fibrotic biomarkers. Results: TAA caused marked histopathological alterations in liver tissues, accompanied by an elevation in hepatic lipid peroxide (MDA, 71.66%), while there was a significant reduction in TAC and GSH levels (64.86% and 56.73%, respectively) in fibrotic rats. Treatment of liver fibrosis with HC showed remarkable improvement, as evidenced by 17.11%, 17.78%, and 71.66% reductions in TAC, GSH, and MDA, respectively, compared with the silymarin reference drug (26.13%, 26.18%, 95%, and 95.00%, respectively). Marked elevation in liver function enzyme activities in serum of fibrotic rats reached 184.15%, 436.13% and 470.57%, respectively, for ALP, ALT, and AST. Upon treatment of fibrotic rats with HC, more or less normalization in the liver enzymes with improvement percentages of 96.79%, 190.29%, and 170.00%, respectively, for ALP, ALT, and AST, compared to the standard drug (105.96%, 291.67%, and 225.61%). The present results showed a significant increase in TGF-β and type IV collagen, while a significant reduction in metalloproteinase-9 (MMP-9) was observed in TAA-induced liver fibrosis with percentages of 368.96%, 104.23% and 35.34%, respectively. A noticeable improvement in the fibrotic markers post-treatment of HC extract reached 160.83%, 73.24%, and 14.81% for TGF-β, type IV collagen, and MMP-9, respectively, compared to the Silymarin reference drug. Discussion: The creation of fibrosis and cirrhosis models in rats is a well-established technique that involves the delivery of TAA both orally and intraperitoneally. TAA is a necrogenic sulfur-containing molecule and a carcinogen. It is frequently employed to cause fulminant hepatic failure and liver cirrhosis in animal models. During the biotransformation of TAA, the enzymes flavin-containing monooxygenase (FMO) and cytochrome P450 facilitate the conversion of dioxygen into superoxide anion, leading to the production of hydrogen peroxide (H2O2). As a result, oxidative stress-related liver damage occurs, and the release of liver enzymes into the circulation is associated with an elevation in inflammatory markers and collagen deposition. The administration of crude extract from Harpullia cupanioides effectively decreased the oxidative damage and inflammation in the liver caused by TAA administration. In particular, the treatment of crude extract made MDA, TAC, IL-6, and TNF-α levels roughly normal, reversing the effects of TAA-induced hepatic fibrosis in rats, this may be due to Harpullia cupanioide's potent antioxidant activity it possesses anti-inflammatory properties that modulate the immunological response of macrophages, restrict the secretion of proinflammatory cytokines (TNF-α and IL-6) and reverse the course of fibrosis, steatosis, and inflammation by repressing macrophage activation. Conclusion: The effects of HC were found to be similar to those of Silymarin, a natural antioxidant, suggesting that the extract may possess anti-inflammatory and anti-fibrotic properties. The findings of this study further demonstrated the anti-inflammatory effects of this plant. However, further research is recommended to investigate its therapeutic potential in treating inflammatory disorders.