Mycobacterial PE12 protein promotes bacterial survival through inhibiting cell apoptosis.

Mycobacterial PE_PGRS family proteins play key roles in pathogen-host interaction. However, the function of most PE_PGRS proteins remains unknown. In this study, we characterized the role of PE12 of Mycobacterium bovis (M. bovis) on bacterial growth, bacterial survival, and host cell apoptosis. Transcriptome sequencing of infected THP-1 cells was also performed. Compared to Ms_Vec, we found that M. bovis PE12 did not alter the colony morphology of M. smegmatis. The survival of Ms_PE12 was obviously higher than that of Ms_Vec. Furthermore, PE12 significantly suppressed the apoptosis of THP-1 induced by M. smegmatis infection. Transcriptome analysis results showed that there were 70 downregulated genes in the Ms_PE12 infection group in comparison with the Ms_Vec infection group, and these differentially expressed genes were enriched in 240 downregulated GO terms and 6 KEGG pathways. The downregulated expression genes are involved in cell adhesion, phagocytosis, apoptosis, inflammatory response, glycolysis and transmembrane transporter activity. Taken together, our study reveals that PE12 can suppress apoptosis and inhibit proinflammatory cytokine response. We propose that PE12 is related to macrophage phagocytosis and apoptosis, providing useful information to the pathogenic mechanisms of M. bovis.

Exploring the pharmacological mechanism of compound kushen injection in the treatment of breast cancer using in vitro experiments: Coupling network pharmacology with GEO database.

Background: Breast cancer (BC) is one of the most common malignant tumors in women and poses a serious threat to their health. Compound Kushen injection (CKI) has shown therapeutic effects on a variety of cancers, including BC, and it can significantly improve the lives of patients. However, the underlying mechanism remains unclear and needs to be fully elucidated. Methods: The active constituents of CKI were identified through a literature review, and the anti-BC targets of CKI were determined using multiple databases and a ChIP data analysis. Subsequently, the target was analyzed on the DAVID database through GO and KEGG to identify the key pathway that CKI affects to exhibit anti-BC activity. In addition, MCF-7 and MDA-MB-231 cells were treated with CKI for 24 and 48 hours at five concentrations, and the effects of CKI on cell proliferation and apoptosis were measured using MTT and annexin V/propidium iodide staining assays, respectively. The genes and protein identified to be involved in this pathway were verified using real-time quantitative PCR (qPCR) and western blot(WB) in BC cells. Results: Twelve CKI anti-BC targets were obtained by a comprehensive analysis of the targets collected in the databases and results from the ChIP analysis. Bioinformatics analysis was performed for 12 targets. KEGG analysis showed that the 12 targets were mainly related to the VEGF, ErbB, and TNF signaling pathways. We focused our study on the VEGF signaling pathway as the p-value for the VEGF signaling pathway was the lowest among the three pathways. In vitro experiments showed that CKI significantly inhibited the proliferation of BC cells and induced apoptosis. Furthermore, qPCR and WB experiments showed that the expression of VEGF signaling pathway genes PIK3CA and NOS3 were significantly increased meanwhile SRC was significantly decreased after CKI intervention. Conclusion: CKI significantly inhibited the proliferation of BC cells and induced apoptosis. The main mechanism for the anti-BC effect of CKI may be that it regulates the VEGF signaling pathway by increasing the expression of PIK3CA, SRC, and NOS3. Macrozamin and lamprolobine may be the main active components of CKI against BC.

Hepatoprotective effect of total flavonoids of Mallotus apelta (Lour.) Muell.Arg. leaf against carbon tetrachloride-induced liver fibrosis in rats via modulation of TGF-ß1/Smad and NF-κB signaling pathways.

ETHNOPHARMACOLOGICAL RELEVANCE: The Mallotus apelta (Lour.) Muell.Arg. is a well-known traditional Chinese medicine (TCM) used for anti-inflammatory, hemostasis and chronic hepatitis. AIM: The purpose of this study was to explore the antifibrotic effect of total flavonoids of Mallotus apelta leaf (TFM) and its potential mechanism. METHODS: Hepatic fibrosis was induced by carbon tetrachloride (CCl4) in rats. The CCl4-induced rats received intragastric administration of colchicine (0.2 mg/kg per day), TFM (25, 50, 100 mg/kg per day) and the equal vehicle was given to normal rats. Pathological evaluation in hepatic tissue were examined by hematoxylin and eosin (HE) staining. And the levels of serum biochemical parameters were detected by automatic biochemical analysis. Meanwhile, the collagen deposition in liver was observed by staining with Masson's trichrome. Collagenic parameters and inflammatory factors were measured by enzyme-linked immunosorbent assay (ELISA) kits. Additionally, corresponding assay kit was used to estimate the antioxidant enzyme and lipid peroxidation. In order to explore the potential mechanism of anti-fibrotic effects in TFM, the expressions of liver fibrosis related gene and protein were analyzed by real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot. RESULTS: The CCl4-induced hepatic fibrosis were inhibited dose-dependently in rats by TFM. The results showed that the key hallmarks of liver injury including aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), albumin (ALB) and total protein (TP) in the serum were reversed in CCl4-induced hepatic fibrosis rats which were treated by TFM. Furthermore, TFM significantly alleviates collagen accumulation and reduces the contents of hydroxyproline (Hyp), Type III precollagen (PC-III), collagen I (Col I), hyaluronic acid (HA) and laminin (LN). RT-PCR and Western blot results showed that TFM markedly inhibits liver fibrosis hallmark factor α-smooth muscle actin (α-SMA) expressions in CCl4-induced hepatic fibrosis rats. Moreover, TFM alleviated the oxidative stress and lipid peroxidation in rats induced by CCl4. TFM also attenuated the pro-inflammatory cytokines including interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) via inhibiting nuclear factor-κB (NF-κB) activation. Meanwhile, transforming growth factor-ß1 (TGF-ß1)/Smad signaling pathway was inhibited by TFM treatment. CONCLUSIONS: TFM can alleviate CCl4-induced hepatic fibrosis in rats, which potential mechanism may be due to its ability of reducing ECM accumulation, improving antioxidant and regulating TGF-ß1/Smad signaling pathways and NF-κB-dependent inflammatory response.

Oral administration of docosahexaenoic acid activates the GDNF-MAPK-CERB pathway in hippocampus of natural aged rat.

CONTEXT: Docosahexaenoic acid (DHA) is one of the critical fatty acids for optimal health, which affect the expression of nerve growth factor and brain-derived neurotrophic factor in brain. OBJECTIVE: This study investigates whether DHA supplementation affects lipid peroxidation and activates the glial-derived neurotrophic factor (GDNF)-mitogen-activated protein kinase pathway (MAPK pathway) in hippocampus of natural aged rat. MATERIALS AND METHODS: Rats were randomly divided into four groups; DHA was orally administered at 80 and 160 mg/kg/day to 24-month female rats for 50 days. The antioxidant parameters and GDNF-GDNF family receptor α-1 (GFRα1)-tyrosine-protein kinase receptor (RET)-MAPK-cyclic AMP response element-binding protein (CERB) pathway were assayed in natural aged rat's hippocampus. RESULTS AND DISCUSSION: The results demonstrated that DHA supplementation significantly increased the activities of superoxide dismutase (SOD) by 37.39 and 57.69%, glutathione peroxidase (GSH-Px) by 27.62 and 32.57% decreased TBARS level by 28.49 and 49.05%, respectively, but did not significantly affect catalase (CAT), in hippocampus, when compared with the aged group. DHA supplementation in diet resulted in an increase of DHA level in hippocampus. Furthermore, we found that DHA supplementation markedly increased the levels of GDNF and GFRα1 and the phosphorylation of RET, and led to the activation of the MAPK pathway in hippocampus tissue. CONCLUSION: DHA supplementation can change fatty acids composition, improve antioxidant parameters and activate the GDNF-MAPK pathway in natural aged rat's hippocampus.

[Metabolism of mangiferin by human intestinal bacteria in vitro].

OBJECTIVE: To study the metabolism of mangiferin by human intestinal bacteria in vitro. METHOD: Human intestinal bacteria and mangiferin were incubated under anaerobic conditions in vitro. The metabolite was separated and purified by D101 macroporous resin column and preparation high performance liquid chromatography, and its structure was identified by MS and NMR. RESULT: After 12 h incubation with human intestinal bacteria, the content of mangiferin metabolite reached the maximum, and it was determined as 1, 3, 6, 7-tetrahydroxyxanthen by MS and NMR. CONCLUSION: Mangiferin can be metabolized in vitro by human intestinal bacteria into its aglycone (1, 3, 6, 7-tetrahydroxyxanthen).

[Hypoglycemic effect of extracts of cactus pear fruit polysaccharide in rats].

OBJECTIVE: To study the hypoglycemic effect and mechanism of the extracts of cactus pear fruit polysaccharide (CPFP) in diabetic rats induced by streptozotocin (STZ). METHODS: The diabetic rats were induced by STZ in SD rats, and randomly divided into model group, insulin group,cactus pear juice group, high dose CPFP group,low dose CPFP group. The experimental rats were administrated for 8 weeks. During the experiment, the contents of blood glucose and blood limit of the rats were detected and body weight were recorded. The pathology of beta cell and alpha cell in pancreas of experimental rats were observed by immunohistochemistry. RESULTS: Compared with model group, the contents of blood glucose, total cholesterol and triglyceride were remarkably decreased in high and low dose CPFP groups. At the same time the body weight was significantly increased in high dose and low dose CPFP groups. The results of immunohistochemical stain demonstrated that the number of islet beta cells was increased and that of islet alpha cells was unchanged in the treatment groups. CONCLUSION: CPFP can markedly decrease blood glucose and blood limit in STZ-induced diabetic rats. Its mechanism may be related to stimulating the secretion of insulin from beta cells.