Evaluation of Immunomodulatory (humoral As Well As Cell-Mediated) and Cytokines (Tnf-Α & IL-10) Regulating Potential of Neolamarckia Cadamba Fruit Extract in Wistar Albino Rats

Current work has been designed to investigate the immunomodulatory efficacy with particular reference to humoral, cell-mediated and cytokine-modulating potential of hot aqueous extract of Neolamarckia cadamba (HAENC) fruits in Wistar albino rats. The effect of different concentrations of HAENC fruits over cell-mediated immune response was assessed using six groups (Gp-I as control, Gp-II with 20 µg/mL, Gp-III with 50 µg/mL, Gp-IV with 100 µg/mL, Gp-V with 250 µg/mL, and Gp-VI with 500 µg/mL) of Wistar albino rats having six animals in each. The amount of tumor necrosis factor-α (TNF-α) and interleukin (IL)-10 was measured by sandwich ELISA with different concentrations of HAENC (50–500 µg/mL) in splenocyte culture supernatant and their expression was determined by qRT-PCR Humoral immune response was determined by measuring the serum antibody titer of Wistar albino rats against Salmonella typhimurium ‘O’ antigen using four groups containing six animals each (Gp-I as control, Gp II, III & IV were respectively fed orally with 125, 250, and 500 mg/Kg body weight using HAENC fruits). LC–MS analysis suggested the presence of cadambine, chlorogenic acid, cadambagenic acid, stearic acid, octadecanoic acid ethyl ether, and 7-hydroxy-5,2'-4'-trimethoxyflavonon in the extract based on their m / z ratio. The result suggested significant ( p < 0.01) dose-dependent proliferation of Concanavalin A (Con A)-treated splenocytes, depicting cell-mediated immunostimulatory potential of HAENC fruits. A dose-dependent significant decrease ( p < 0.01) was found in the amount of TNF-α and IL-10 was found to increase significantly ( p < 0.01) as extract concentrations increased. TNF-α and IL-10 expressions were confirmed at the molecular level by qRT-PCR analysis of mRNA transcripts of TNF-α and IL-10 genes. Fold expression of TNF-α and IL-10 gene was 0.197 and 3.58 at 250 µg/mL, 0.02 and 20.11 at 500 µg/mL concentrations of HAENC respectively in comparison to control. Serum antibody titer was significantly increased ( p < 0.01) in animals fed with different doses of HAENC fruits. The present study suggested the anti-inflammatory effect of HAENC fruits which also influences the networking of cytokines, implying that it may play a role in regulating the activity of the host's immune system and can serve as a potent herbal drug with immuno-stimulatory potential.