Background: Oxidative stress-induced endothelial cell death, such as apoptosis and autophagy, plays a critical role in ischemia-reperfusion injury. Protocatechualdehyde (PCA) is a major bioactive component of the traditional Chinese medicine Salvia miltiorrhiza Bunge (Lamiaceae), and it has been proved to be effective in the prevention and treatment of ischemic cardiovascular and cerebrovascular diseases. However, its role in oxidative stress-induced endothelial cell death and its underlying mechanisms remains unclear. This study aims to investigate the effects and mechanisms of PCA on endothelial cell apoptosis and autophagy induced by oxygen-glucose deprivation/reoxygenation (OGD/R) injury.Methods: After OGD/R induction, human umbilical vein endothelial cells (HUVECs) were treated with different concentrations of PCA. Cell viability, apoptosis, and autophagy were detected by Cell Counting Kit-8 assay, flow cytometry, and monodansylcadaverine assay, respectively. Western blot was applied to explore the effects of PCA on the expression levels of relevant protein factors.Results: The results show that PCA significantly promoted cell survival rate and cell proliferation and enhanced the antioxidant activity in OGD/R-induced HUVECs. PCA inhibited HUVECs apoptosis, as evidenced by decreased expression of cleaved-caspase-3, Bcl2-associated X (BAX), and increased expression of Bcl-2. PCA induced autophagy by reducing the expression of P62 while increasing the expression of Beclin-1 and LC3 II/I. Meanwhile, PCA enhanced the expression of Sirtuin 1 (SIRT1) and suppressed the expression of P53. When SIRT1 was inhibited by selisistat or SIRT1 small-interfering RNA, the anti-apoptotic and pro-autophagy abilities of PCA were attenuated.Conclusion: These results demonstrated that PCA rescued HUVECs from OGD/R-induced injury by promoting autophagy and inhibiting apoptosis through SIRT1 and could be developed as a potential therapeutic agent against ischemic diseases.

Background: As a traditional Chinese medicine, Polygonatum has been demonstrated to have immunomodulatory, antibacterial, anti-inflammatory, anti-aging, anti-cancer, hypoglycemic and other pharmacological effects. However, the germplasm resources of Polygonatum have been destroyed in recent years and the research on its genetic diversity is extremely scarce. In this study, the genetic diversity of 28 Polygonatum germplasms from 11 different provinces in China was evaluated by Start codon targeted (SCoT) marker. Results: A total of 365 bands were generated by 15 SCoT primers, of which 355 were polymorphic, with a high polymorphism of 97.3%. And the genetic similarity coefficient is between 0.59 and 0.75, indicating a high genetic diversity. UPGMA (Unweighted Pair Group Method with Arithmetic Mean) dendrogram, PCoA (Principal Coordinate Analysis) and Structure analysis have similar results in grouping Polygonatum germplasm and they are all divided into two populations. We found that there was a certain correlation between the genetic distance and geographical distance of Polygonatum germplasm. By analyzing other valid genetic diversity parameters (Na, Ne, H, I), it is clarified that Polygonatum has abundant alleles and abundant genetic diversity among populations. Conclusions: This study suggests that Polygonatum germplasm resources from different provenances have rich genetic diversity. The SCoT molecular marker is a valuable marker system and can be used for genetic analysis of Polygonatum resources. This will be helpful to further study the preservation and genetic improvement of Polygonatum germplasm.