Objectives: The aim of this study was to investigate the proliferative and protective effects of striatisporolide A (SA) obtained from the rhizomes of Athyrium multidentatum (Doell.) Ching on human umbilical vein endothelial cells (HUVECs). Methods: Cell viability was measured by the MTT method. Cell apoptosis was determined by flow cytometry. Intracellular ROS was measured by the 2,7-dichlorodihydrofluorescein diacetate (DCFH-DA) fluorescent probe. Results: The viability rate in cells treated with 100 µM SA alone was increased to 128.72% ± 0.19% and showed a significant difference compared with the control group (p < 0.05). Meanwhile, SA augmented the cell viabilities in H₂O₂-treated HUVECs, and the cell viability was enhanced to 56.94% ± 0.13% (p < 0.01) when pre-incubated with 50 µM SA. The cell apoptosis rates were reduced to 2.17% ± 0.20% (p < 0.05) and 3.1% ± 0.34% (p < 0.01), respectively, after treatment with SA alone or SA/H₂O₂. SA inhibited the overproduction of reactive oxygen species (ROS) in HUVECs induced by H₂O₂ and the fluorescent intensity was abated to 9.47 ± 0.61 after pre-incubated with 100 μM SA. Conclusions: The biological activities of SA were explored for the first time. Our results stated that SA exhibited significant cytoproliferative and minor cytoprotective effects on HUVECs. We presume that the mechanisms of the proliferation and protection actions of SA involve interference with the generation of ROS and the cell apoptosis. These findings provide a new perspective on the biological potential of butenolides.

It has been reported that oxidative stress plays a prominent role in diabetic macrovascular diseases. 3,4‑Dihydroxyacetophenone (3,4‑DHAP) has been found to have a variety of biological activities. However, few studies have assessed the antioxidant capacity of 3,4‑DHAP and the underlying mechanisms. Thus, the aim of the present study was to explore the effects of 3,4‑DHAP on oxidative stress in human umbilical vein endothelial cells (HUVECs). HUVECs were pre‑treated with 3,4‑DHAP and then exposed to high glucose conditions. Cell viability and cytotoxicity were measured using an MTT assay. Reactive oxygen species (ROS) levels were measured using an inverted fluorescence microscope and a fluorescent enzyme labeling instrument. Protein expression levels of nuclear factor E2‑related factor 2 (Nrf2), heme oxygenase‑1 (HO‑1), microtubule‑associated protein 1A/1B‑light chain 3 (LC3) and poly ADP‑ribose polymerase‑1 (PARP‑1) were measured using western blotting, and mRNA expression of Nrf2 and HO‑1 were measured through reverse transcription‑quantitative PCR (RT‑qPCR). Nrf2 nuclear translocation was evaluated using immunofluorescence analysis and autophagosomes were observed using transmission electron microscope (TEM). The results of the present study demonstrated that compared with the control group, cell viability of the high glucose group was reduced and cell cytotoxicity of the high glucose group was increased. ROS production in the high glucose group was clearly enhanced. In addition, high glucose upregulated Nrf2 and HO‑1 protein and mRNA expression levels. Nuclear translocation of Nrf2 in the high glucose group was also increased. The formation of autophagosomes in the high glucose group was also higher than that in the control group. Furthermore, LC3‑II/LC3‑I and PARP‑1 protein expression levels were increased after treatment with high glucose. However, compared to the high glucose group, 3,4‑DHAP (10 µmol/l) significantly enhanced cell viability. 3,4‑DHAP markedly decreased the production of ROS, increased Nrf2 and HO‑1 protein and mRNA expression levels, and promoted nuclear translocation of Nrf2 in HUVECs. In addition, 3,4‑DHAP promoted the formation of autophagosomes, and notably increased the protein expression levels of LC3‑II/LC3‑I and PARP‑1. Moreover, it was determined that compared to the 3,4‑DHAP group, treatment with 3,4‑DHAP and ML385 enhanced cell viability, and decreased ROS production, Nrf2 and HO‑1 protein and mRNA expression levels, nuclear translocation of Nrf2, and LC3‑II/LC3‑I and PARP‑1 protein expression levels. Collectively, the results of the present study showed that 3,4‑DHAP protected HUVECs against oxidative stress via regulation of the Nrf2/HO‑1 pathway, by increasing autophagy and promoting DNA damage repair.