The Effect of Rosemary (Rosmarinus officinalis. L) Plant Extracts on the Immune Response and Lipid Profile in Mice

The hypolipidemic activity of leaves of rosemary (Rosmarinus officinalis), a herbal plant was
studied. Three groups of BALB/c mice were treated as following: the first group was fed with
normal diet (sugar & water), the second group was fed with high cholesterol (HC) (2% by
weight) and coconut oil (25% by weight), for 36 days, and the third group was fed with HC
diet and given 100 mg/kg rosemary extract (10% w/v) during the last 15 days of treatment
period. There was a significant decrease (P < 0.001) in plasma total cholesterol (TC)(-
68.57%), low density lipoprotein (LDL) (- 56.34%), and triglycerides (TG) (- 182.61%). A
significant increase in high density lipoprotein (HDL) (38.53%) was obtained in
rosemary-fed mice compared to HC mice. In another experiment, the immunomodulatory
activity of aqueous extract of R. officinalis was evaluated in BALB/c mice. Mice were treated
with three doses of extract (10, 50, 100 mg/kg body weight) for 8 weeks. Humoral immunity
against membrane proteins of sheep erythrocytes measured by ELISA showed that IgM
(Immunoglobulin M) response significantly increased by 26.95%, 36.5%, 70.78%
respectively, in mice fed with 10, 50, and 100 mg/kg of rosemary as compared to the control
group (P < 0.05). IgG (Immunoglobulin G) response increased significantly at all antibody
titers, in mice fed with rosemary at doses of 10, 50, and 100 mg/kg. Meanwhile, there was no
significant different in IgM and IgG responses between 50 and 100 mg/kg (P > 0.05). On the
other hand, concanavalin A-stimulated proliferation of spleen cells from mice fed with 100
mg rosemary extract was significantly higher by 57% than that of cells from the
corresponding control animals.