4'-O-methylbavachalcone alleviates ischemic stroke injury by inhibiting parthanatos and promoting SIRT3.

Cerebral ischemia-reperfusion injury (CIRI) can induce massive death of ischemic penumbra neurons via oxygen burst, exacerbating brain damage. Parthanatos is a form of caspase-independent cell death involving excessive activation of PARP-1, closely associated with intense oxidative stress following CIRI. 4'-O-methylbavachalcone (MeBavaC), an isoprenylated chalcone component in Fructus Psoraleae, has potential neuroprotective effects. This study primarily investigates whether MeBavaC can act on SIRT3 to alleviate parthanatos of ischemic penumbra neurons induced by CIRI. MeBavaC was oral gavaged to the middle cerebral artery occlusion-reperfusion (MCAO/R) rats after occlusion. The effects of MeBavaC on cerebral injury were detected by the neurological deficit score and cerebral infarct volume. In vitro, PC-12 cells were subjected to oxygen and glucose deprivation/reoxygenation (OGD/R), and assessed cell viability and cell injury. Also, the levels of ROS, mitochondrial membrane potential (MMP), and intracellular Ca2+ levels were detected to reflect mitochondrial function. We conducted western blotting analyses of proteins involved in parthanatos and related signaling pathways. Finally, the exact mechanism between the neuroprotection of MeBavaC and parthanatos was explored. Our results indicate that MeBavaC reduces the cerebral infarct volume and neurological deficit scores in MCAO/R rats, and inhibits the decreased viability of PC-12 cells induced by OGD/R. MeBavaC also downregulates the expression of parthanatos-related death proteins PARP-1, PAR, and AIF. However, this inhibitory effect is weakened after the use of a SIRT3 inhibitor. In conclusion, the protective effect of MeBavaC against CIRI may be achieved by inhibiting parthanatos of ischemic penumbra neurons through the SIRT3-PARP-1 axis.

VX-509 attenuates the stemness characteristics of colorectal cancer stem-like cells by regulating the epithelial-mesenchymal transition through Nodal/Smad2/3 signaling.

BACKGROUND: Colorectal cancer stem cells (CCSCs) are heterogeneous cells that can self-renew and undergo multidirectional differentiation in colorectal cancer (CRC) patients. CCSCs are generally accepted to be important sources of CRC and are responsible for the progression, metastasis, and therapeutic resistance of CRC. Therefore, targeting this specific subpopulation has been recognized as a promising strategy for overcoming CRC. AIM: To investigate the effect of VX-509 on CCSCs and elucidate the underlying mechanism. METHODS: CCSCs were enriched from CRC cell lines by in conditioned serum-free medium. Western blot, Aldefluor, transwell and tumorigenesis assays were performed to verify the phenotypic characteristics of the CCSCs. The anticancer efficacy of VX-509 was assessed in HCT116 CCSCs and HT29 CCSCs by performing cell viability analysis, colony formation, sphere formation, flow cytometry, and western blotting assessments in vitro and tumor growth, immunohistochemistry and immunofluorescence assessments in vivo. RESULTS: Compared with parental cells, sphere cells derived from HCT116 and HT29 cells presented increased expression of stem cell transcription factors and stem cell markers and were more potent at promoting migration and tumorigenesis, demonstrating that the CRC sphere cells displayed CSC features. VX-509 inhibited the tumor malignant biological behavior of CRC-stem-like cells, as indicated by their proliferation, migration and clonality in vitro, and suppressed the tumor of CCSC-derived xenograft tumors in vivo. Besides, VX-509 suppressed the CSC characteristics of CRC-stem-like cells and inhibited the progression of epithelial-mesenchymal transition (EMT) signaling in vitro. Nodal was identified as the regulatory factor of VX-509 on CRC stem-like cells through analyses of differentially expressed genes and CSC-related database information. VX-509 markedly downregulated the expression of Nodal and its downstream phosphorylated Smad2/3 to inhibit EMT progression. Moreover, VX-509 reversed the dedifferentiation of CCSCs and inhibited the progression of EMT induced by Nodal overexpression. CONCLUSION: VX-509 prevents the EMT process in CCSCs by inhibiting the transcription and protein expression of Nodal, and inhibits the dedifferentiated self-renewal of CCSCs.

Effects of Astragalus membranaceus on systemic lupus erythematosus in a mouse model of pregnancy.

BACKGROUND: This study used astragalus membranaceus (AM) to treat systemic lupus erythematosus (SLE) model mice during pregnancy, aiming to explore the role of AM in Helper T cell 17 (Th17) differentiation and SLE during pregnancy. METHODS: We used lipopolysaccharide to constructed the SLE mouse model. AM decoction given by intragastric administration lasted from the eighth week of the mouse age until the mouse was killed. We estimated the messenger RNA  levels of IL-17a and Rorc, counted the Th17 cell number and examined the levels of cytokines including interleukin (IL)-12, tumor necrosis factor α, interferon gamma, IL-17A in mouse serum. Periodic acid-Schiff staining and renal glomerular/tubulointerstitial (TI) score were used to evaluate the progression of lupus nephritis (LN). RESULTS: AM treatment improved the conception rate and increased the number and average weight of fetuses in SLE mice. It significantly decreased the urinary albumin/creatinine ratios and reduced the glomerular scores and TI scores in the pregnant SLE mice. AM gavage significantly decreased the weight of spleen, mesenteric lymph node, total splenocytes and T cells, and the expression of proinflammatory factors. Furthermore, AM treatment reduced the ratio of Th17 cells and the expression levels of RORγt and IL-17A. CONCLUSION: AM significantly improved pregnancy outcomes and inhibited lupus nephritis during pregnancy in SLE mice.

[Significance of beta-catenin and Cyclin D1 express in glioma].

AIM: To investigate the expression and the significance of beta-catenin and Cyclin D1 in gliomas. METHODS: The SABC immunohistochemistry were used to detect the expression of beta-catenin and Cyclin D1 in 49 brain gliomas and 5 normal brain tissues. RESULTS: The beta-catenin positive ratio in normal brain tissues and glioma samples are 2/5 and 38/49(P<0.01) respectively, and the Cyclin D1 positive ratio in normal brain tissues and gliomas are 1/5 and 42/49(P<0.01); Compared with the normal brain tissue, both the immunohistochemical expression of beta-catenin and Cyclin D1 were up-regulated(P<0.05), and the expression of beta-catenin and Cyclin D1 between the normal brain tissues and gliomas exhibited significantly difference (P<0.01). CONCLUSION: beta-catenin and Cyclin D1 increased in gliomas may be precipitate the tumorigenesis of glioma.

[Flow injection analysis of trace amounts of doxycycline with inhibited chemiluminescence detection].

A novel flow injection chemiluminescence method has been developed for the determination of doxycycline (DC) based on the inhibition of chemiluminescence reaction of Luminol-KMnO4 by using DC in sodium hydroxide medium. Using different concentrations of KMnO4, a series of good linear regression equations of decreased chemiluminescence intensity and the concentration of DC were obtained with different subsections in the concentration range of 0.005-5.0 microg x mL(-1). The detection limit (3sigma) is 2.0 x 10(-3) microg x mL(-1). The method has been successfully applied to the determination of DC in a pharmaceutical preparation.