OBJECTIVE:

            To evaluate antiarthritic and anti-inflammatory activity of Solanum nigrum leaves extract on CFA-induced arthritic rat model.

METHODOLOGY:

            It was a 4-week pre-clinical experimental study, including 30 male Wistar albino rats divided in 5 groups as; Group-I Negative control, Group-II Positive control; Group-III Methotrexate (MTX); Group-IV Solanum nigrum (SN) 100mg/kg; Group-V Solanum nigrum (SN) 200mg/kg. Arthritis was induced by administering 0.1mL of CFA in right hind paw from Group-II to Group-V at day 0. Intraperitoneal injections of 0.9% normal saline (Group-I and II); MTX (Group-III), SN100 (Group-IV) and SN200 (Group-V) were administered at days 0, 7, 14 and 21. Paw size was measured by using Vernier caliper on day 0, 7, 14, 21 and 28. On the 29^th day, animals were anesthetized by an intraperitoneal injection of pentobarbital 100mg/kg and 10ml of blood was collected by cardiac puncture. Serum was separated by centrifugation to analyze IL-1, IL-2, IL-6, TNF-α and PG-E2 by ELISA. Results were analyzed by using SPSS version 22. ANOVA was applied for intergroup and intragroup comparison. P-value <0.05 will be considered significant at 95% confidence interval.

RESULTS:

            Paw circumference was significantly and equally decreased in MTX, SN100 and SN200 groups when compared with positive control group showing equal efficacy of SN as an anti-inflammatory agent. ELISA results revealed significant increase in all pro-inflammatory cytokines (IL-1, IL-2, IL-6, TNF-α and PG-E2) is positive control group. MTX and herbal treatment groups (IV and V) significantly suppressed these cytokines but SN200 exhibited maximum reduction.

CONCLUSION:

            Solanum nigrum can be used as an effective adjunctive with standard DMARDs like MTX to increase the efficacy in the treatment of rheumatoid arthritis.