Anti-endotoxin effects of terpenoids fraction from Hygrophila auriculata in lipopolysaccharide-induced septic shock in rats

Context: Hygrophila auriculata (K. Schum) Heine (Acanthaceae) has been traditionally used for the treatment of various ailments such as inflammation, rheumatism, jaundice and malaria.

Objective: The present study aims to separate terpenoid fraction (TF) from alcohol (70%) extract of the whole plant of Hygrophila auriculata and assess its anti-inflammatory activity.

Materials and methods: HPTLC analysis of TF was performed for the estimation of lupeol. Edema was induced in Wistar albino rats by subplanter injection of 0.1?ml of 1% (w/v) carrageenan into the right hind paw after 1?h of TF administration (100 and 200?mg/kg oral). Septic shock was induced by intraperitoneal administration of LPS (100?μg/kg) in rats and interleukins (IL-1β and IL-6), tumor necrosis factor (TNF-α), superoxide dismutase (SOD), lipid peroxidation (LPO), and nitric oxide (NO) were measured in serum. AutoDock 4.2 was used for molecular docking.

Results: Administration of TF significantly (p?0.005) restored the serum levels of cytokines, LPO (7.77?±?0.034 versus 4.59?±?0.059?nmole of TBARS), NO (9.72?±?0.18 versus 4.15?±?0.23?µmol nitrite/mg of wet tissue), and SOD (4.89?±?0.036 versus 7.83?±?0.033?Unit/mg protein) compared with the LPS-challenged rats. Analysis of in silico results revealed that TNF-α is the most appropriate target in eliciting anti-inflammatory activity.

Conclusion: The present findings suggest that TF of Hygrophila auriculata possesses great promise as an anti-inflammatory agent which may be due to its antioxidant effect. Molecular docking results could be exploited for lead optimization and development of suitable treatment of inflammatory disorders.