Restoration of Electric Footshock-Induced Immunosuppression in Mice by <em>Gynostemma pentaphyllum </em>Components

Abstract

The immunomodulatory effects of the ethanol extract of <em>Gynostemma pentaphyllum </em>(GP-EX) were examined in electric footshock (EFS)-stressed mice. The mice were orally administered various doses of GP-EX for 7 days before exposure to EFS (duration: 3 min, interval: 10 s, intensity: 2 mA) once a day from day 8 for 14 days with continuous daily feeding of GP-EX. Oral administration of GP-EX to mice prevented EFS stress-induced immunosuppression as determined by the lymphoid organ (thymus and spleen) weight and cellularity. In addition, oral administration of GP-EX restored EFS-suppressed functional properties of mature lymphocytes in terms of concanavalin A-induced proliferation of splenocytes and lipopolysaccharide-induced cytokine production (TNF-α, IL-1β). Furthermore, we found that mice that were orally administered with GP-EX generated much more potent ovalbumin-specific cytotoxic T lymphocyte responses upon intravenous ovalbumin injection compared to the untreated controls. These results demonstrate that oral administration of the ethanol extract of <em>Gynostemma pentaphyllum</em> could increase host defense in immunocompromised situations such as stress-induced immunosuppression.

Keywords

• &lt;em&gt;Gynostemma pentaphyllum&lt;/em&gt;
• electric footshock
• stress
• immunomodulation
• cytotoxic T lymphocytes