Grape Seed Extract Attenuates Demyelination in Experimental Autoimmune Encephalomyelitis Mice by Inhibiting Inflammatory Response of Immune Cells / 中国结合医学杂志

OBJECTIVE@#To examine the anti-inflammatory effect of grape seed extract (GSE) in animal and cellular models and explore its mechanism of action.@*METHODS@#This study determined the inhibitory effect of GSE on macrophage inflammation and Th1 and Th17 polarization in vitro. Based on the in vitro results, the effects and mechanisms of GSE on multiple sclerosis (MS)-experimental autoimmune encephalomyelitis (EAE) mice model were further explored. The C57BL/6 mice were intragastrically administered with 50 mg/kg of GSE once a day from the 3rd day to the 27th day after immunization. The activation of microglia, the polarization of Th1 and Th17 and the inflammatory factors such as tumor necrosis factor- α (TNF- α), interleukin-1 β (IL-1 β), IL-6, IL-12, IL-17 and interferon-γ (IFN-γ) secreted by them were detected in vitro and in vivo by flow cytometry, enzyme linked immunosorbent assay (ELISA), immunofluorescence staining and Western blot, respectively.@*RESULTS@#GSE reduced the secretion of TNF-α, IL-1 β and IL-6 in bone marrow-derived macrophages stimulated by lipopolysaccharide (P<0.01), inhibited the secretion of TNF-α, IL-1 β, IL-6, IL-12, IL-17 and IFN-γ in spleen cells of EAE mice immunized for 9 days (P<0.05 or P<0.01), and reduced the differentiation of Th1 and Th17 mediated by CD3 and CD28 factors (P<0.01). GSE significantly improved the clinical symptoms of EAE mice, and inhibited spinal cord demyelination and inflammatory cell infiltration. Peripherally, GSE downregulated the expression of toll-like-receptor 4 (TLR4) and Rho-associated kinase (ROCKII, P<0.05 or P<0.01), and inhibited the secretion of inflammatory factors (P<0.01 or P<0.05). In the central nervous system, GSE inhibited the infiltration of CD45+CD11b+ and CD45+CD4+ cells, and weakened the differentiation of Th1 and Th17 (P<0.05). Moreover, it reduced the secretion of inflammatory factors (P<0.01), and prevented the activation of microglia (P<0.05).@*CONCLUSION@#GSE had a beneficial effect on the pathogenesis and progression of EAE by inhibiting inflammatory response as a potential drug and strategy for the treatment of MS.

Mechanism of bilobalide promoting neuroprotection of macrophages / 中国中药杂志

This study aims to explore the neuroprotective effect of bilobalide(BB) and the mechanisms such as inhibiting inflammatory response in macrophage/microglia, promoting neurotrophic factor secretion, and interfering with the activation and differentiation of peripheral CD4~+ T cells. BB of different concentration(12.5, 25, 50, 100 μg·mL~(-1)) was used to treat the RAW264.7 and BV2 cells for 24 h. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay and cell counting kit-8(CCK-8) were employed to detect the cytotoxicity of BB and appropriate concentration was selected for further experiment. Lipopolysaccharide(LPS) was applied to elicit inflammation in RAW264.7 and BV2 cells, mouse bone marrow-derived macrophages(BMDMs), and primary microglia, respectively. The effect of BB on cell proliferation and secretion of inflammatory cytokines and neurotrophic factors was detected by enzyme-linked immunosorbent assay(ELISA). Spleen monocytes of C57BL/6 female mice(7-8 weeks old) were isolated, and CD4~+ T cells were separated by magnetic beads under sterile conditions. Th17 cells were induced by CD3/CD28 and the conditioned medium for eliciting the inflammation in BMDMs. The content of IL-17 cytokines in the supernatant was detected by ELISA to determine the effect on the activation and differentiation of CD4~+ T cells. In addition, PC12 cells were incubated with the conditioned medium for eliciting inflammation in BMDMs and primary microglia and the count and morphology of cells were observed. The cytoto-xicity was determined by lactate dehydrogenase(LDH) assay. The result showed that BB with the concentration of 12.5-100 μg·mL~(-1) had no toxicity to RAW264.7 and BV2 cells, and had no significant effect on the activity of cell model with low inflammation. The 50 μg·mL~(-1) BB was selected for further experiment, and the results indicated that BB inhibited LPS-induced secretion of inflammatory cytokines. The experiment on CD4~+ T cells showed that the conditioned medium for LPS-induced inflammation in BMDMs promoted the activation and differentiation of CD4~+ T cells, while the conditioned medium of the experimental group with BB intervention reduced the activation and differentiation of CD4~+ T cells. In addition, BB also enhanced the release of neurotrophic factors from BMDMs and primary microglia. The conditioned medium after BB intervention can significantly reduce the death of PC12 neurons, inhibit neuronal damage, and protect neurons. To sum up, BB plays a neuroprotective role by inhibiting macrophage and microglia-mediated inflammatory response and promoting neurotrophic factors.

Effects of gestational weight on the association between serum high sensitivity C reaction protein and gestational diabetes mellitus among twin gestations: A cohort study / 北京大学学报(医学版)

OBJECTIVE@#To investigate the association between serum high sensitivity C-reaction protein (hsCRP) in early pregnancy and gestational diabetes mellitus (GDM) among twin pregnant women, and to explore the effects of the pre-pregnant body mass index (BMI) and gestational weight gain (GWG) status on such association.@*METHODS@#Twin pregnant women with pre-pregnant BMI greater than or equal to 18.5 kg/m2 were recruited at Department of Obstetrics and Gynecology of Peking University Third Hospital from March 2017 to December 2020. Serum samples collected in early pregnancy were analyzed for hsCRP using particle-enhanced immunoturbidimetric method. In the following visits, the information about GWG and GDM were prospectively collected in every trimester. The association effect between hsCRP tertiles and GDM were estimated using Logistic regression, and further converted into risk ratio (RR). Cochran-Mantel-Haenszel test and mediation analysis were used to explore the effects of BMI and GWG status on the association.@*RESULTS@#Among the included 570 twin pregnant women, 31.6% deve-loped GDM, 26.1% were pre-pregnant overweight or obesity, and 49.5% with GWG out of referenced range. After adjustment for confounding factors, risk of developing GDM in twin gestations with the middle tertile and highest tertile of serum hsCRP in early pregnancy were 1.42 fold (95%CI: 1.02-1.89) and 1.54 fold (95%CI: 1.12-2.02), respectively, compared with the lowest tertile of serum hsCRP, and there existed significantly linear trend (P=0.022). Findings from mediation analysis illustrated that pre-pregnant BMI had partial mediating effect on the association, and BMI accounted for 23.84% (P < 0.001) of the increasing GDM risks with elevated hsCRP. Joint analysis with hsCRP and GWG found that those who were with GWG out of referenced range accompanied with the higher hsCRP tertiles (>1.21 mg/L) had significantly 2.31 fold increased risk according to those who were with GWG in the referenced range accompanied with the lowest hsCRP tertile (≤1.21 mg/L, P < 0.01).@*CONCLUSION@#Elevated hsCRP in early pregnancy significantly increased GDM risk among twin pregnant women. The hsCRP-GDM association was dependent on GWG status, and pre-pregnant BMI had partial mediating effect on such association. It is suggested that twin pregnant women should consider systemic inflammation and gestational weight at the same time to reduce GDM risk.

Associations of distribution of time spent in physical activity and sedentary behavior with obesity / 北京大学学报(医学版)

OBJECTIVE@#To explore associations of distribution of time spent in physical activity (PA) and sedentary behavior (SB) with obesity with taking account that time is finite during the day of adult residents in Wuhai City.@*METHODS@#A cross-sectional study was undertaken in Wuhai City, and we carried out a sampling of local residents aged 18-79 by using multiple stratified cluster sampling method. Data about social demographic characteristics, time spent in PA and SB, diet intake, controlling situation of chronic disease and other covariates were obtained by qualified investigators for face-to-face questionnaire survey. Data about height, weight, and waist circumstance, were obtained by doctors in a secondary hospital or above for body measurements. The statistical method used in our study was known as compositional data analysis, which had been used to process compositional data in many fields. Liner regression analysis with compositional data was used to synthetically analyze the associations of distribution of time spent in PA and SB with obesity,and to investigate the effect of re-allocating time from one behavior to another one whilst the remaining one was kept stable.@*RESULTS@#The investigation revealed the special advantage of compositional data analysis in processing time-use data. The result of liner regression analysis with the compositional data showed that after controlling the potential confounding factors, the associations of distribution of time spent in PA and SB was significantly associated with body mass index (BMI, P<0.001) and the negative natural logarithm of waist to height ratio (-lnWHtR, P<0.001). Among them, in professional population, the proportion of time spent in moderate-to-vigorous physical activity (MVPA) was negatively correlated with -lnWHtR (β=-0.008, P=0.022), while the proportion of time spent in SB was positively correlated with BMI and -lnWHtR (β=0.117, P=0.003; β=0.007, P=0.005). However, in nonprofessional population, the proportion of time spent in MVPA was only negatively correlated with BMI (β=-0.079, P=0.041). Nevertheless, the proportion of time spent in low-intensity physical activity (LIPA) was not significantly associated with BMI and -lnWHtR in both professional and nonprofessional population. In addition, the effects of MVPA replacing another behavior and of MVPA being displaced by another behavior were not symmetrical, and 10 minutes of MVPA replacing LIPA or SB had a greater influence on intervention and prevention of obesity than 10 minutes MVPA being replaced by LIPA or SB.@*CONCLUSION@#The research has resulted in a solution of the associations of the distribution of time spent in PA, SB with health risk. Our results suggest that public health messages should target the health effects of the distribution of time of PA and SB synergistically in developing PA guidelines and health management practice, rather than simply increasing or decreasing the absolute time of PA or SB, so that we can provide scientific suggestions to make people get a profounder healthy effect.