Effect Of Tryptophan On Regulation Of Immune Function Neurotransmitter And Behavior For Stress Mice

The investigation was conducted to evaluate the effect of tryptophan on Immune Suppression and Chronic Unpredictable Stress (CUS) model mice, in addition, the related index were analyzed, then use the effect of tryptophan on oxidative stress, immune system,levels of monoamine neural transmitter and spatial learning ability et al to further discuss the possible mechanisms of tryptophan on immune system and the role of anti-stress.Immune Suppression model, 60 mice were divided randomly into 4 groups: the normal control group(NC), CTX group, CTX-L group, CTX-H group. During the experiment, intraperitoneal injection of cyclophosphamide, irrigation stomach saline and tryptophan. when the experiment was end, collect samples of blood and organs, neutral red method was used to measure macrophages cell engulf ability, IFN-γand cortisol content were measured by ELISA kit. Chronic Unpredictable Stress model, 60 mice were divided as follows: the normal control group(NC), the chronic unpredictable stress(CUS) group, low-dose tryptophan(CUS-L) group, high-dose tryptophan (CUS-H) group. During the experiment, irrigation stomach saline and tryptophan. when the experiment was end, collect samples of blood and organs, 5-HT and NE content were measured by ELISA kit, morris water maze was used to measure the spatial learning and memory of stress mice.The results were as follows: (1) Tryptophan can decrease the level of reactive oxygen species ROS and the content of lipid peroxide MDA in stress mice(P<0.05), increase the ability of total antioxidant capacity T-AOC and superoxide dismutase SOD(P<0.05). (2) Tryptophan can enhance the viscera index of stress mice, increase abdominal macrophages cell engulfed ability and splenic lymphocytes proliferation ability, add IFN-γand IL-2 content in serum(P<0.05), but reduce IgG and cortisol level in serum(P<0.05). (3) Trp can shorten the escape latency of stress mice in orientation navigation experiment(P<0.05),also shorten the first time that stress mice reach the platform and increase number of times for mice cross the platform in space search experiment(P<0.05). (4) Trp can increase 5-HT content in hypothalamus(P<0.05), and reduce NE in hypothalamu(sP<0.05), also trp can improve the sugar water preference and prolong the ice water swimming time of stress mice(P<0.05) Conclusion: Tryptophan can increase anti-oxidative capacity and reduce oxidative stress of CTX stress mice; After supplementation of tryptophan for immune suppression mice, level of serum IFN-γwas elevated while level of serum cortisol was descended, also the abdominal macrophages cell ability and spleen lymphocyte proliferation ability were increased, which mean tryptophan can improve immune system of immune suppression mice caused by CTX; On the other hand, the supplementation of tryptophan can increased level of hypothalamus 5-HT and decreased level of hypothalamus NE, also time for ice water swimming of stress mice was extended which enhanced anti-fatigue capability of stress mice, meanwhile, level of serum IL-2 was elevated while content of serum IgG was descended, all changes show that tryptophan can regulate the immunity, special learning memory ability and behavior of stress mice.