A potential association between Toxoplasma gondii infection and schizophrenia in mouse models.

Schizophrenia is a serious neuropsychiatric disease of uncertain etiology, which causes human mental disorder and affects about 1% of the population. In recently years, some studies showed that some cases of schizophrenia may be associated with Toxoplasma gondii infection. In order to investigate a potential association between Toxoplasma infection and schizophrenia, we investigated the relative clinical symptom of schizophrenia such as learning and memory capability, depression and stereotypy to find some useful information by behavioral test in mouse models. Our results demonstrated that mice from Toxoplasma infection and MK-801 administration (as the model of schizophrenia) were impaired in learning and memory capability, and they had more serious depression and stereotypy compared with the control mice, especially the mice from congenital Toxoplasma infection. In addition, our results clearly showed that the number of cysts in brain tissue of congenital Toxoplasma infection mice was significantly low than in acquired Toxoplasma infected mice. Collectively, these results suggested a potential association between Toxoplasma infection and schizophrenia.

[Study on the processing technique of enzyme hydrolysis Eupolyphaga sinensis peptide and innunoregulatory effect].

OBJECTIVE: Using papain to prepare polypeptide from Eupolyphaga sinensis, then study the immune function of polypeptide from Eupolyphaga sinensis in vivo. METHODS: Used hydrolysis degree as index, pH value, enzyme dosage, thermometer reaction time were optimized. Studied the influence of polyeptide on the mice immune functions through mice immune organs index, phagocytic function and the level of IL-2. RESULTS: The optimum enzymolysis condition was as follows: pH 8.0, enzyme 1%, temperature 55 degrees C, reaction time 4. 5 h. In vivo test of mice demonstraed that, Eupolyphaga sinensis could elevate index of thymus and spleen, enhance the phagocytic function of macrophage and promote the level of IL-2 in serum. CONCLUSION: Eupolyphaga sinensis has immunoregulatory effect.

[Effects of neonatal isolation stress on hyperlocomotion of complexin II knockout mouse].

The aim of this study was to investigate the influence of neonatal isolation stress on hyperlocomotion in complexin II knockout mouse (Cplx2(-/-)). The mice were randomly divided into 4 groups: Cplx2(-/-) with stress, Cplx2(+/+) with stress, Cplx2(-/-) without stress and Cplx2(+/+) without stress. Isolation stress was employed on the pups of stress groups from the 2nd day after the postnatal to the 21st day. The PCR was used to determine the gene type and the hyperlocomotion test was employed to detect the change of animal behavior after methamphetamine or saline injection (i.p.). The results showed that the animals of all groups increased their movement after injection of 0.2 mg/kg methamphetamine in different levels (P < 0.01), compared with those injected with saline. The Cplx2(-/-) mouse with stress revealed a significant increase in the distance of free movement after injection of 0.2 mg/kg methamphetamine compared with the knockout mouse without stress (P < 0.001). When Cplx2(-/-) mouse with stress was compared with wild type with stress, Cplx2(-/-) mouse with stress had more movement (P < 0.001), indicating that Cplx2 has effect on the hyperlocomotion as well. These results suggest an involvement of stress and Cplx2 in the movement behavior of mice.

[Study on purification and property of polysaccharide from Scolopendra subspinipes mutilans].

OBJECTIVE: To obtain polysaccharide from Scolopendra subspinipes mutilans and study its partial properties. METHODS: A raw polysaccharide was isolated from Chinese medicine Scolopendra subspinipes mutilans, and three groups were isolated by DEAE-52. The thin layer chromatography and gel filtration chromatography were used to detect the main monosaccharide composition and molecular weight of the group I. The inhibitory effect of the group I on tumor cells was detected by MTT assay. RESULTS: The molecular weight of the group I was 33.1 kD. The inhibitory effect of the group I on Hela cells was obvious, as its inhibitive rate was 60.8% on Hela cells when the polysaccharide's concentration was 3.13 microg/mL, but it had no effect on the Eca 109 cells. CONCLUSION: The group I has specific effects on different tumor cells.

[Expression of miR-140-5p and prediction of its target gene in human mesenchymal stem cells during adipogenic differentiation].

OBJECTIVE: To screen the differentially expressed miRNAs and their target genes in adipogenic differentiation of human bone marrow mesenchymal stem cells (hMSCs) to better understand the mechanism for regulating the balance between osteoblast and adipocyte differentiation. METHODS: Cultured hMSCs were induced for adipogenic differentiation, and at 0, 7, 14, and 21 days of induction, the cells were examined for miRNA and mRNA expression profiles using miRNA chip and transcriptome sequencing (RNA-seq) techniques. Correlation analysis was carried out for the miRNAs and mRNAs of potential interest. The databases including TargetScan, PicTar and miRanda were used to predict the target genes of the differentially expressed miRNA. RESULTS: The expression of miR-140-5p was down-regulated and leukemia inhibitory factor receptor (LIFR) expression increased progressively during adipogenic differentiation of hMSCs, showing a negative correlation between them. Target gene prediction using the 3 databases identified LIFR as the target gene of miR-140-5p. CONCLUSION: miRNA-140-5p may play an important role by regulating its target gene LIFR during adipogenic differentiation of hMSCs.