[Toxic effect and mechanism of Tripterygium glycosides on ovarian germline stem cells of mice in vitro by Notch signaling pathway].

The ovarian germline stem cells(OGSCs) cultured in the optimized culture system were used as the research object to observe the effect of Tripterygium glycosides(TG) on OGSCs and explore the mechanism of reproductive toxicity by the Notch signaling pathway. Cell counting kit-8(CCK-8) was used to observe the viability level of OGSCs in mice cultured in vitro by TG of 3.75, 7.5, and 15 µg·mL~(-1). Immunofluorescence technology and reverse transcription-polymerase chain reaction(RT-PCR) were used to detect the protein and gene expression level of OGSCs marker mouse vasa homologue(MVH) and octamer-binding transcription factor 4(Oct4) by TG of 3.75 µg·mL~(-1). RT-PCR detected the gene expression of neurogenic locus Notch homolog protein 1(Notch1), Hes family BHLH transcription factor 1(Hes1), and jagged canonical Notch ligand 1(Jagged1). The RNA was extracted for transcriptome analysis to analyze the mechanism of action of TG intervention on OGSCs. 3.75 µg·mL~(-1) of TG was combined with 40 ng·mL~(-1) Notch signaling pathway γ-secretagocin agonist jagged canonical notch ligand(Jagged) for administration. CCK-8 was used to detect the viability level of OGSCs. Double immunofluorescence technology was used to detect the protein co-expression of MVH with Hes1, Notch1, and Jagged1. The results showed that compared with the blank group, the TG administration group significantly inhibited the activity of OGSCs(P<0.01 or P<0.001). It could reduce the protein and gene expression of OGSC markers, namely MVH and Oct4(P<0.05, P<0.01, or P<0.001). It could significantly inhibit the gene expression of Notch1, Hes1, and Jagged1(P<0.001). Transcriptomic analysis showed that TG affected the growth and proliferation of OGSCs by intervening Jagged1, a ligand associated with the Notch signaling pathway. The experimental results showed that the combination of Notch signaling pathway γ-secretagorein agonist Jagged could significantly alleviate the decrease in OGSC viability induced by TG(P<0.001) and significantly increased the OGSC viability compared with the TG group(P<0.001). It also could significantly increase the co-expression of MVH/Jagged1, MVH/Hes1, and MVH/Notch1 proteins(P<0.01 or P<0.001). It suggested that TG play the role of γ-secretagorease inhibitors by downregulating the OGSC markers including MVH and Oct4 and Notch signaling pathway molecules such as Notch1, Hes1, and Jagged1, participate in the OGSC pathway, and mediate reproductive toxicity caused by the Notch signaling pathway.

[Salvianolic acid B alleviate the disruption of blood-brain barrier in rats after cerebral ischemia-reperfusion by inhibiting MAPK pathway].

The aim of the study is to investigate the effect of salvianolic acid B (SalB) on blood-brain barrier (BBB) in rats after cerebral ischemia-reperfusion, and to illustrate its possible mechanisms. Cerebral ischemia-reperfusion was induced by middle cerebral artery occlusion in rats. The break-down of BBB was indicated by extravasations of immunoglobulin (IgG) monitored with immunohistochemistry. The expression of MMP-9 and NOS2 in the brain was determined by immunohistochemistry, and the expression of p-p38 and p-ERK1/2 was detected by Western blotting. It was shown that on day 2 after ischemia-reperfusion the IgG accumulated around the vascular boundary zone, suggesting the break-down of BBB, and the expression of MMP-9 and NOS2 up-regulated at the same time. The result of Western blotting suggested that the expression of p-p38 and p-ERK1/2 increased. On day 7 after ischemia-reperfusion the. expression of MMP-9 and NOS2 was about the same level as day 2, the expression of p-p38 was higher than that on day 2 and the expression of p-ERK1/2 was slightly lower than that on day 2. SalB (1 and 10 mg x kg(-1)) significantly alleviated the extravasations of immunoglobulin induced by cerebral ischemia-reperfusion (P < 0.05). On day 2 and day 7 SalB attenuated the expression of MMP-9 and NOS2 (P < 0.05). SalB (10 mg x kg(-1)) reduced the expression of p-p38 and p-ERK1/2 apparently on day 2 and 7 after ischemia-reperfusion (P < 0.05). SalB (1 mg x kg(-1)) inhibited the expression of p-p38 on day 7 after ischemia-reperfusion (P < 0.05). The results indicate that SalB protects blood-brain barrier in rats after cerebral ischemia-reperfusion by inhibiting the MAPK pathway.