Anti-inflammatory activity of Nerium indicum by inhibition of prostaglandin E2 in murine splenic lymphocytes.
OBJECTIVE
Nerium indicum Mill (syn. N. oleander L. and N. odorum Aiton; family: Apocynaceae) is a medicinal plant, used in the treatment of diverse ailments including various chronic inflammatory diseases in traditional medicine. We have previously demonstrated the immunomodulatory activity of a bioactive fraction of Nerium indicum leaf (NILE) by studying up-regulation of interleukin-2 (IL-2), IL-10, interferon-gamma and down regulation of IL-4, tumor necrosis factor-alpha (TNF-α), nitric oxide, cyclooxygenase-1 (COX-1) and COX-2 activities. Therefore, this study aimed to confirm the anti-inflammatory activity of NILE by inhibition of prostaglandin E₂ (PGE₂) activity in murine splenic lymphocytes in vitro.


METHODS
Murine lymphocytes were isolated from spleen and stimulated with 5 ΅g/mL concanavalin A in RPMI-1640, supplemented with 50 U/mL penicillin, 50 U/mL streptomycin, 50 U/mL nystatin and 10% fetal bovine serum. Different concentrations (0-80 μg/mL) of NILE were added and the cells were cultured for 48 h. The culture supernatants were thereafter collected by centrifugation and assayed for expression of PGE₂ level. The data were analyzed statistically.


RESULTS
The results demonstrated a 2.26-fold inhibition of PGE2 level at 80 μg/mL of NILE. Half maximum inhibitory concentration (IC₅₀) was calculated to be 44.95 ± 0.45 ΅g/mL. Linear correlation analysis of the dose-dependent PGE₂ inhibition with other pro- and anti-inflammatory mediators demonstrated high inter-correlation between the parameters.


CONCLUSIONS
Thus, the present study remains in accordance with our previous report and confirms the anti-inflammatory claim of N. indicum, mentioned in the traditional medicine.
Department of Zoology, Cellular Immunology Laboratory, University of North Bengal, Siliguri, West Bengal, India.
Priyankar
P
Dey
Department of Zoology, Cellular Immunology Laboratory, University of North Bengal, Siliguri, West Bengal, India.
Tapas Kumar
TK
Chaudhuri
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D015232:Dinoprostone / Q000037:antagonists & inhibitors*; D004305:Dose-Response Relationship, Drug; D007249:Inflammation / Q000188:drug therapy / Q000473:pathology; D018836:Inflammation Mediators / Q000378:metabolism; D020128:Inhibitory Concentration 50; D008214:Lymphocytes / Q000187:drug effects / Q000378:metabolism; D008519:Medicine, Traditional; D051379:Mice; D030007:Nerium / Q000737:chemistry*; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology*; D018515:Plant Leaves; D013154:Spleen / Q000166:cytology
D000893:Anti-Inflammatory Agents; D018836:Inflammation Mediators; D010936:Plant Extracts; D015232:Dinoprostone
Anti-inflammatory; cyclooxygenase; lymphocyte; nerium; prostaglandin