Evaluation of the Neuroendocrine System and the cytokine pattern in warm and cold nature persons

Introduction: Traditional Iranian medicine (TIM) is accompanied by little side effects in experience. The mechanisms involved in TIM are not much clear. The purpose of this study is assessment of differences of warm and cold nature persons in neuroendocrine system and cytokine pattern (Th1/Th2) of immune responses. Methods: Thirty seven 20 to 40 years old male volunteers were divided into 2 groups of warm and cold nature using a standard questioner. Warmth/coldness ratio of all volunteers was assessed according the results of the questioner. Plasma concentrations of epinephrine, norepinephrine, cortisol and the concentration of IFN-γ and IL-4 produced by peripheral blood mononuclear cells were measured. Results: The results showed that norepinephrine/epinephrine and norepinephrine/cortisol ratios in the hot nature volunteers were significantly more than cold nature volunteers. The IL-4/IFN-γ ratio in the hot nature group was more than in the cold nature group and this difference was approximately significant (P = 0.08). Also there was a significant positive linear correlation between the norepinephrine/epinephrine and warmth/coldness ratio (P = 0.008) and a nonlinear significant association between IL-4/IFN-γ and warmth/coldness ratio (P = 0.022). Conclusion: Therefore, it can be deduced that the hot nature persons had a more peripheral sympathetic nervous system activity, less adrenal sympathetic, adrenal corticosteroid and parasympathetic nervous system activities and more deviation of immune system toward Th2 responses. Also the activity of sympathetic nervous system was increased and adrenal sympathetic was decreased with growing of warmth/coldness ratio. When the nature went toward severe warmth or severe coldness, the deviation of immune system toward Th2 like responses would increase, but this increasing was very more severe with going toward severe warmth than that of going toward severe coldness.