Induction of Anti-inflammatory and Altered T-Cell Proliferative Responses by the Ethanol Root Extract of Plumbago zeylanica. in Adjuvant-Induced Arthritic Rats

ABSTRACT

The ethanol root extract of Plumbago zeylanica. L. (PZE) was investigated for anti-inflammatory activity in adjuvant-induced arthritic (AIA) rats. The AIA rats were treated with PZE (20 mg/kg body weight) daily from day 0 to day 13. The PZE reduced the paw thickness and paw volume of AIA rats. The effect of PZE treatment was assessed in cutaneous delayed type hypersensitivity (DTH) response to Mycobacterium. tuberculin (MT) in development of AIA. The results demonstrated that PZE inhibited the development of cutaneous DTH response in AIA rats. The T-cell proliferation induced by concanavalin A (Con A), a mitogen, was depressed in three different strains of AIA rats (Wistar, Lewis, and Fischer) when compared with that of normal; however, the PZE treatment of AIA rats reversed the decrease of T-cell proliferation to the normal levels. The treatment of AIA rats with PZE on splenic T-cell proliferation was also compared with T-cell proliferation of rats that were treated with the known anti-inflammatory compounds such as cyclophosphamide and indomethacin.

Keywords:

• Adjuvant-induced arthritis
• anti-inflammatory activity
• Con A
• intraperitoneal
• mitogen
• Plumbago zeylanica
• subcutaneous
• T-cell proliferation