Study on the promotion effect mechanism of ethanol extract from Atractylodes macrocephala on microglia phagocytosis and degradation of Aβ based on regulating PPAR-γ signaling pathway / 中国药房

OBJECTIVE To explore the effect mechanism of ethanol extract from Atractylodes macrocephala （EEAM） on microglial phagocytosis and degradation of amyloid β （Aβ） based on peroxisome proliferator-activated receptor γ （PPAR- γ） signaling pathway. METHODS Taking neuromicroglial cell BV2 as subjects， confocal microscopy was used to observe the effects of EEAM （0.3， 0.4， 0.5 mg/mL， similarly hereinafter） on phagocytosis and degradation of Aβ in microglia. Human embryonic kidney cell HEK293 was used to investigate the effects of EEAM on luciferase transcriptional activity of PPAR-γ. The effect of EEAM on nuclear translocation of PPAR-γ was investigated by immunofluorescence. Alzheimer’s disease BV2 cell model was induced by Aβ1-42， and quantitative polymerase chain reaction was used to investigate the effects of EEAM on mRNA expressions of PPAR-γ downstream target genes （Lxra， Lxrb， Abca1， Abcg1， Cd36， Sra and Apoe）. RESULTS The results of Aβ uptake experiment showed that after the intervention of medium and high doses of EEAM， fluorescence intensity of Aβ in BV2 cells increased significantly （P＜0.05）. The degradation experiment of Aβ showed that after the intervention of medium and high doses of EEAM， fluorescence intensity of Aβ in BV2 cells decreased significantly （P＜0.05）. After the intervention of different doses of EEAM， luciferase transcriptional activity of PPAR-γ in HEK293 cells increased significantly （P＜0.05）； fluorescence intensity of PPAR-γ in BV2 cells and nuclei （except for low-dose group） increased significantly （P＜0.05）. mRNA expressions of Lxra， Lxrb， Abca1， Abcg1， Cd36， Sra and Apoe in BV2 cells were increased significantly （P＜0.05）. CONCLUSIONS EEAM can promote the uptake and degradation of Aβ in microglia by activating PPAR-γ signaling pathway， thus improving Alzheimer’s disease.

The toxic effects of imidacloprid exposure on HepG2 cell based on non-targeted metabolomics / 环境与职业医学

Background Imidacloprid is a neonicotinoid insecticide that is widely used in agricultural production, with a high detection rate in human biological samples. Previous studies have shown a high correlation between imidacloprid exposure and liver injury, but the specific mechanism is still unknown. Objective To observe potential toxic effects of HepG2 cells and its perturbation of non-targeted metabolic profile after imidacloprid exposure, and to explore possible molecular mechanisms of hepatotoxicity of imidacloprid by analyzing invovlved biological processes and signaling pathways. Methods HepG2 cell suspension was prepared and seeded in a 96-well plate, which was divided into blank control group, dimethyl sulfoxide (DMSO) solvent control group and imidacloprid exposure groups with multiple concentrations. Each group was set with 5 parallel samples. The viability of HepG2 cells viability were determined after 8 h of exposure to different concentrationsof imidacloprid (1, 2.5, 5, 7.5, 10 mmol·L−1), and the dose-effect relationship was analyzed. A proper concentration (3 mmol·L−1 with 80% viability) was chosen for imidacloprid exposure, non-targeted metabolomic analysis was applied to the cultivated HepG2 cells using UHPLC-Q-TOF/MS technology, the differential metabolites between groups were screened, and the bioprocess and related signaling pathways of their enrichment were annotated using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Results Compared to the other two groups, the survival rates of HepG2 cells in the imidacloprid exposure groups decreased. A survival rate of about 86% of HepG2 cells was found in HepG2 cells exposed to 2.5 mmol·L−1 imidacloprid exposure. The non-targeted metabolomics studies showed that 61 metabolites were significantly affected in HepG2 cells after 3 mmol·L−1 imidacloprid exposure, including creatine (variable importance in projection VIP=1.11, P<0.001), arginine (VIP=1.47, P=0.048), taurine (VIP=4.28, P=0.001), and α-D-glucose (VIP=1.90, P=0.006). The differential metabolites enriched in bioprocess and related signaling pathways were mainly directed to mTOR signaling pathways (P<0.001), arginine and proline metabolism (P=0.002), and galactose metabolism (P=0.015). Conclusion Imidacloprid exposure can significantly inhibit the survival rate of HepG2 cells, and interfere with the mTOR signaling pathway, arginine and proline metabolism, galactose metabolism, and so on.

Study on the mechanism of Yishen tongluo formula improving abnormal lipid metabolism based on SREBPs pathway / 中国药房

OBJECTIVE To explore the mechanism of Yishen tongluo formula （YSTLF） in improving abnormal lipid metabolism based on the sterol regulatory element binding proteins （SREBPs） pathway. METHODS Using C57BLKS/J （db/db） mice as model and C57BLKS/J （db/m） mice as normal control， the mechanism of 1， 2.5 and 5 g/kg YSTLF improving abnormal lipid metabolism of db/db mice was investigated by determining the liver coefficient， the contents of serum total cholesterol （TC）， triglyceride （TG）， low-density lipoprotein （LDL） and high-density lipoprotein （HDL）， observing steatosis and lipid accumulation in liver tissue of mice， detecting the protein expressions of SREBP-1 and SREBP-2 as well as mRNA transcription levels of Srebp- 1c， Srebp-2 and their downstream lipid metabolism-related target genes （Fasn， Acc1， Scd5， Fads1， Hmgcr， Dhcr24， Insig-1， Fdps） in liver tissue of mice. Using low-fat cultured human liver cancer cell HepG2 as an in vitro cell model for abnormal lipid metabolism， and 25-HC （SREBPs inhibitor， 10 μmol/L） as the control， the effects of 125， 250 and 500 μg/mL YSTLF on protein expressions of SREBP-1 and SREBP-2 as well as mRNA transcription of SREBP-1c， SREBP-2 and their downstream lipid metabolism-related target genes were investigated to verify the mechanism in vitro. RESULTS 1， 2.5， 5 g/kg YSTLF significantly reduced the levels of TC， TG and LDL， the percentage of lipid droplet-positive region in liver tissue and liver coefficient， significantly down-regulated protein expressions of Pre-SREBP-1， n-SREBP-1， Pre-SREBP-2 and n-SREBP-2， and mRNA transcription of Srebp-1c， Srebp-2 and their downstream target genes in liver tissue， while significantly increased HDL level， with statistical significance （P＜0.05 or P＜0.01）. In the cell experiment in vitro， the expressions of the above-mentioned proteins and genes in the cells treated with YSTLF at 125， 250 and 500 μg/mL for 24 hours were consistent with those in the animal experiment； there was no significant difference in the expressions of the above-mentioned proteins and genes between inhibitor control group and 250， 500 μg/mL YSTLF groups （P＞0.05）. CONCLUSIONS YSTLF can regulate the expression of transcription factor SREBPs， so as to inhibit the high expression of fatty acid and cholesterol synthesis-related genes， promote the degradation of TC and TG， improve the abnormality of lipid metabolism and inhibit lipid accumulation， thus playing the role of lipid-lowering.

Optimization of SARS-CoV-2 spike protein receptor binding domain expression in Pichia pastoris and evaluation of its immunogenicity / 中华微生物学和免疫学杂志

Objective:To effectively express the receptor binding domain (RBD) of SARS-CoV-2 spike protein in Pichia pastoris and to evaluate its immunogenicity. Methods:The gene encoding the RBD protein was synthesized and cloned into the pPICZαA plasmid. After linearization, the plasmid was transferred and integrated into the genome of Pichia pastoris. The expressed RBD protein in culture supernatant was analyzed by Western blot and Biolayer interferometry. After screening, a single clone expressing the RBD protein was selected. The high-level expression of RBD protein was achieved by optimizing the fermentation process, including the salt concentration adjusting of the medium and induction condition optimization (pH, temperature and duration). The immunogenicity of the expressed RBD protein was evaluated in a mouse model. Results:A single clone with a high expression level of RBD protein was obtained and named RBD-X33. The expression level of RBD protein in the fermentation supernatant reached up to 240 mg/L after optimization of the induction condition (HBSM medium, pH=6.5±0.3, 22℃ and 120 h). In the mouse experiment, the recombinant RBD protein was formulated with Alum+ CpG dual adjuvant and injected into mice. The binding IgG antibody levels were up to 2.7×10 6 tested by ELISA and the neutralizing antibody levels were up to 726.8 tested by live virus neutralizing antibody assay (prototype). Conclusions:The RBD protein could be efficiently expressed in Pichia pastoris and induce stronger immune response in animals. This study suggested that the recombinant SARS-CoV-2 RBD protein expressed in Pichia pastoris could serve as a candidate antigen in the development of SARS-CoV-2 vaccine.

Effect of age on urodynamic parameters of women with urinary incontinence / 北京大学学报(医学版)

Objective:To investigate age related changes in urodynamic parameters of women with uri-nary incontinence.Methods:From May 2008 to October 2015,a total of 214 patients diagnosed with urinary incontinence in Peking University People’s Hospital was involved in this study.Average age was (56.97 ±10.68)years,ranging from 30 to 82 years,and average history was (8.44 ±8.85)years, ranging from one month to 50 years.Urodynamic examinations of each patient were taken before operation routinely in Department of Urology,Peking University People’s Hospital.The urodynamic study was composed of non-invasive and invasive procedures.Analysis included maximal flow rate (Qmax ),average flow rate,time to Qmax ,voiding time,detrusor pressure at Qmax ,maximal detrusor pressure,voided volume,post-void residual urine volume (PVR),the total capacity of bladder,first-,strong-,and urge-desire to void,cough leak point pressure (CLPP),and Valsalva leak point pressure (VLPP).Patients were divided into four groups according to age,Kolmogorov-Smirnov test and one-way ANOVA were used for data analysis.Results:A total of 214 patients were enrolled in this study.The data of Qmax ,average flow rate,voided volume,and total capacity of bladder decreased with statistical significance.The value of residual urine volume and voiding time increased without statistical significance,while the value of maximal detrusor pressure decreased.Conclusion:Urodynamic examination data of females with urinary incontinence changes along with the elapse of age,which was mainly observed as age ascends,and the changes in urodynamic parameters of women with urinary incontinence suggest that the value of Qmax , average flow rate,voided volume,and total capacity of bladder decreased significantly,while the value of PVR and the voiding time increased and the value of maximal detrusor pressure decreased.

The synergistic effect of lidamycin and rituximab on human B cell lymphoma / 药学学报

This study aimed to investigate the synergistic effect of lidamycin (LDM) and rituximab on human B cell lymphoma Ramos cells. Cell proliferation was measured using MTS assay, cell apoptosis was analyzed by Annexin V-FITC/PI assay, the expression of apoptosis related proteins was analyzed by Western blotting, and the in vivo lymphoma inhibition was verified using BALB/c mice inoculated via tail vein using Ramos cells which stably expressed pEGFP-N1 plasmid. The results showed that, after the pretreatment with rituximab for 48 h, rituximab and LDM showed significantly synergistic effects on cell proliferation. Cells in combined treatment group had a higher apoptosis rate than that in LDM treatment group. Compared with the LDM treatment group, the expression of apoptosis-related proteins such as Cleaved caspase-3, Cleaved caspase-7, Cleaved caspase-9 and Cleaved PARP in combined treatment groups increased, and expression of cIAP-2 and Bcl-2 decreased. The result of in vivo experiment showed that, in the combined treatment group, the survival time of BALB/c mice was significantly longer than the mice in control group and LDM treatment group, and the degree of tumor accumulation and metastasis to lymph nodes and spleen was lower.