Relationship Between Serum Protein Factors And Clinical Symptoms In First-episode Schizophrenic Patients

Objective:1. To investigate the serum levels of interleukin 6 (IL-6), Calcium binding protein (S100β), Neurotrophin-3 (NT-3), and the association with these serum levels with scores of PANSS in schizophrenic patients characterized by positive or negative symptoms.2. To investigate the relationship between the serum concentration of IL-6, S100β, NT-3 and the cognitive functions in schizophrenic patients characterized by positive or negative symptoms.Methods: ①The study was case-control study. The serum concentration of three protein factors in 44 schizophrenic patients characterized by positive symptoms、38 schizophrenic patients characterized by negative symptoms and 78 healthy controls were assayed by ELISA respectively. PANSS was used to evaluate the symptoms of patients with first-episode schizophrenia. ②And the system evaluation tool-MCCB was applied to assess cognitive function in 44 schizophrenic patients characterized by positive symptoms,36 schizophrenic patients characterized by negative symptoms and 50 healthy controls. The correlation between the serum levels of three protein factors and their cognitive function and the correlation between the scores of PANSS and their cognitive function in the three groups were investigated.Results:The first study ① The difference of IL-6 serum levels in three groups was statistically significant (F=31.338, P<0.01), further pairwise comparisons, the IL-6 serum levels in control group was lower than those in the group of positive symptoms and negative symptoms groups. IL-6 concentrations in positive symptoms group is lower than those in negative symptoms group; ②The difference of S100β serum level in three groups was statistically significant (F= 9.18, P<0.01), further pairwise comparisons, the S100 β serum levels in control group were lower than those in the group of positive symptoms and negative symptoms groups; ③The difference of NT-3 serum level in three groups was statistically significant (F= 10.45. P<0.01), further pairwise comparisons, NT-3 serum levels in control group was higher than those in the positive symptoms or negative symptoms group. Based on analysis of the correlation between serum proteins and PANSS scores in patients characterized by positive symptoms or negative symptoms, we found that the NT-3 concentration in the patients with positive symptoms was statistically associated with the general symptom scores in PANSS (P<0.05). However, no statistical correlation was found in other correlation analysis(P>0.05) The second study①In cognition part, IL-6、S100 β concentrations in schizophrenic patients characterized by positive or negative symptoms were higher than those in healthy controls and the different was statistically significant. NT-3 concentrations in schizophrenic patients characterized by positive or negative symptoms were lower than those in healthy controls and the different was statistically significant. Furthermore, IL-6 concentrations in schizophrenic patients characterized by positive symptoms were lower than those in schizophrenic patients characterized by negative symptoms [5.07±1.17)vs(5.74± 0.999)ng/L] and the different was statistically significant. ② In schizophrenic patients characterized by positive symptoms, there were a positive correlation between the IL-6 serum concentration and the BVMT-R score in MCCB(r=0.365, P<0.01), and a positive correlation between the NT-3 serum concentration and the BVMT-R score in MCCB(r=0.39, P<0.01).Conclusions:The first study ①The IL-6, S100β serum concentration of in schizophrenic patients characterized by positive or negative symptoms were significantly higher than the control group, but the NT-3 level in schizophrenic patients characterized by positive or negative symptomswas lower than the control group. It shows during pro-inflammatory state, nerve injury and nerve nutritional deficiencies have been in existence in the early stages of schizophrenia. ② IL-6 serum concentrations in schizophrenic patients characterized by positive symptoms are lower than those in patients characterized by negative symptoms (P<0.05), however the level of S100-β, NT-3 were no significant differences between these two groups.This implies the inflammatory reaction in the first-episode schizophrenia characterize by negative symptoms was stronger than that of the first-episode schizophrenia characterize by positive symptoms. We speculated that with schizophrenia characterize by positive and negative symptoms may have different pathological mechanisms. The second study ① According to the study of cognitive function, the results of the three groups of peripheral serum protein concentrations were in agreement with the first study. The TMT scores in patients characterize by positive symptoms or patients characterize by negative symptoms were higher than those in healthy control group, BACS SC, HVLT-R WMS-Ⅲ, SS, NAB, BVMT-R, CF in patients characterize by positive symptoms or by negative symptoms were lower than those in healthy control group. There were no statistical difference in the MCCB scores between the patients with positive symptoms and negative symptoms. It indicates that the overall cognitive function in the early stage of schizophrenia was significantly lower than that of the healthy control group. The cognitive function of the patients characterize by positive symptoms was the same as that of the patients characterize by with negative symptoms. The IL-6 serum concentration and NT-3 concentration in the patients characterize by positive symptoms were positively correlated with the BVMT-R score in the MCCB test. However in the patients characterize by negative symptoms and the control group, there was no correlation between cytokines and their MCCB scores. There was no significant correlation between PANSS scores and MCCB test scores in each group. It suggested that the serum protein factors may be related to the cognitive impairment in schizophrenic patients.