SIRT1/Nrf2/NF-κB Signaling Mediates Anti-Inflammatory and Anti-Apoptotic Activities of Oleanolic Acid in a Mouse Model of Acute Hepatorenal Damage

Medicina (Kaunas). 2023 Jul 24;59(7):1351. doi: 10.3390/medicina59071351.

Abstract

Background and objectives: Oleanolic acid (OA) is a penta-cyclic triterpene with diverse bioactivities such as anticarcinogenic, antiviral, antimicrobial, hepatoprotective, anti-atherosclerotic, hypolipidemic, and gastroprotective. However, its effects on hepatorenal damage remain unclear. The protective activity of OA, separated from Viscum schimperi (Loranthaceae), against TAA (thioacetamide)-produced acute hepatic and renal damage was explored. Materials and Methods: Mice were treated with OA for 7 days before TAA (200 mg/kg, i.p.). Serum indices of hepatorenal injury, pathological lesions, molecular biological indexes, and inflammatory/apoptotic genes were estimated. Results: The tissues of both organs were greatly affected by the TAA injection. That was evident through increased serum markers of hepato-renal injury as well as remarkable histopathological lesions. TAA-induced injury was associated with oxidative and inflammatory responses in both organs as there was an elevation of oxidative stress parameters (4-HNE (4-hydroxy-nonenal), MDA (malondialdehyde), NOx (nitric oxide)), decline of antioxidants (reduced glutathione (GSH), superoxide dismutase (SOD), and total antioxidant capacity (TAC)), and an increase in the gene expression/level of inflammatory mediators (interleukins (1β&6)). The inflammatory response was linked to a significant activation of NF-κB (nuclear-factor kappa-B)/TNF-α (tumor-necrosis factor-alpha) signaling. The inflammatory response in both organs was accompanied by apoptotic changes, including a rise in the gene expression and level of apoptotic parameters (caspase-3 and Bax) along with a decline in Bcl-2 (anti-apoptotic parameter) gene expression and level. These pathogenic events were found to be closely related to the suppression of the antioxidant signaling pathway, Nrf2 (nuclear-factor erythroid 2-related factor-2)/SIRT1 (sirtuin-1)/HO-1 (heme-oxygenase 1). On the other hand, OA significantly ameliorated TAA-induced injury in both organs. On the other hand, OA counterpoised the inflammatory response as it ameliorated NF-κB/TNF-α signaling and cytokine release. OA enhanced Nrf2/SIRT1/HO-1 signaling and counteracted apoptotic damage. Conclusions: OA showed anti-inflammation and antiapoptotic capacities that effectively suppressed TAA-induced acute hepatorenal damage.

Keywords: Bax/Bcl-2; SIRT1/Nrf2/NF-κB; Viscum schimperi; drug discovery; health and wellbeing; hepatorenal damage; oleanolic acid; thioacetamide.

MeSH terms

  • Animals
  • Anti-Inflammatory Agents / pharmacology
  • Anti-Inflammatory Agents / therapeutic use
  • Antioxidants / metabolism
  • Mice
  • NF-E2-Related Factor 2 / genetics
  • NF-kappa B* / metabolism
  • Oleanolic Acid* / pharmacology
  • Oleanolic Acid* / therapeutic use
  • Oxidative Stress
  • Signal Transduction
  • Sirtuin 1 / metabolism
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Anti-Inflammatory Agents
  • Antioxidants
  • NF-E2-Related Factor 2
  • NF-kappa B
  • Oleanolic Acid
  • Sirtuin 1
  • Tumor Necrosis Factor-alpha