Icariin alleviates ferroptosis-related atherosclerosis by promoting autophagy in xo-LDL-induced vascular endothelial cell injury and atherosclerotic mice.

Vascular endothelial cells (VECs) are located between the blood plasma and the vascular tissue, and the ferroptosis (iron-dependent programmed cell death) of VECs can lead to a range of cardiovascular diseases. Icariin is the main active ingredient of Epimedium brevicornum Maxim., which can improve endothelial cell dysfunction. In the present study, the protective effects of icariin on oxidised low-density lipoprotein (ox-LDL)-treated VECs and high-fat diet-fed Apolipoprotein E-deficient mice were investigated. Inflammatory fibrosis in tissues and inflammatory factors in serum and cell supernatants were detected, and mitochondrial membrane potential and the expression levels of ferroptosis-associated proteins were also detected. The results revealed that icariin reduced the endothelial atherosclerotic plaque area and collagen fibres in aortic sinus tissue, and increased the viability and mitochondrial membrane potential, whereas it reduced the reactive oxygen species levels of VECs. The nucleation of transcription factor EB (TFEB) and subsequent autophagy were negatively associated with ferroptosis in endothelial cells, and the more prominent the autophagy, the lower the levels of ferroptosis. Furthermore, by co-treating the cells with icariin and the two autophagy inhibitors, Bafilomycin A1 (blocking autophagosome and lysosome fusion) and 3-methyladenine (blocking autophagosome formation), respectively, the promoting effects of icariin on autophagy were found to be mediated through the process of autophagosome-lysosome fusion. In in vivo experiments, icariin reduced ferroptosis, alleviated atherosclerotic lesions and increased the rate of TFEB nucleation. Additionally, it was found that ARG304, THR308 and GLN311 were the optimal binding sites for the interaction between icariin and TFEB. Taken together, these results suggest that the fusion of autophagosomes and lysosomes promoted by icarrin enhances autophagy and thus reduces ferroptosis. Therefore, icariin may be a potential candidate for the prevention of ferroptosis of VECs and, thus, for the treatment of cardiovascular diseases.

[Astragali Radix-Curcumae Rhizoma combination inhibits proliferation, migration, and invasion of colon cancer HT-29 cells by regulating EMT].

This study aims to investigate the effect of Astragali Radix-Curcumae Rhizoma(AC) combination on the proliferation, migration, and invasion of colon cancer HT-29 cells based on epithelial-mesenchymal transition(EMT). HT-29 cells were respectively treated with 0, 3, 6 and 12 g·kg~(-1) AC-containing serum for 48 h. The survival and growth of cells were measured by thiazole blue(MTT) colorimetry, and the proliferation, migration, and invasion of cells were detected by 5-ethynyl-2'-deoxyuridine(EdU) test and Transwell assay. Cell apoptosis was examined by flow cytometry. The BALB/c nude mouse model of subcutaneous colon cancer xenograft was established, and then model mice were classified into blank control group, 6 g·kg~(-1) AC group, and 12 g·kg~(-1) AC group. The tumor weight and volume of mice were recorded, and the histopathological morphology of the tumor was observed based on hematoxylin-eosin(HE) staining. The expression of apoptosis-associated proteins B-cell lymphoma-2-associated X protein(Bax), cysteine-aspartic acid protease-3(caspase-3), and cleaved caspase-3, and EMT-associated proteins E-cadherin, MMP9, MMP2 and vimentin in HT-29 cells and mouse tumor tissues after the treatment of AC was determined by Western blot. The results showed that cell survival rate and the number of cells at proliferation stage decreased compared with those in the blank control group. The number of migrating and invading cells reduced and the number of apoptotic cells increased in the administration groups compared with those in the blank control group. As for the in vivo experiment, compared with the blank control group, the administration groups had small tumors with low mass and shrinkage of cells and karyopycnosis in the tumor tissue, indicating that the AC combination may improve EMT. In addition, the expression of Bcl2 and E-cadherin increased and the expression of Bax, caspase-3, cleaved caspase-3, MMP9, MMP2, and vimentin decreased in HT-29 cells and tumor tissues in each administration group. In summary, the AC combination can significantly inhibit the proliferation, invasion, migration, and EMT of HT-29 cells in vivo and in vitro and promote the apoptosis of colon cancer cells.

Salvianolic acid A alleviates atherosclerosis by inhibiting inflammation through Trc8-mediated 3-hydroxy-3-methylglutaryl-coenzyme A reductase degradation.

BACKGROUND: Atherosclerosis is the most prevalent cardiovascular disease and remains the major contributor to death and mortality globally. Salvianolic acid A (SalA) is a water-soluble phenolic acid that benefits atherosclerosis. However, the mechanisms of SalA protecting against atherosclerosis remain unclear. PURPOSE: We aimed to determine whether SalA prevents atherosclerosis by modulating 3-Hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) degradation via the ubiquitin-proteasomal pathway. METHODS: The animal and cellular models of atherosclerosis were established by subjecting apolipoprotein E (ApoE) knockout mice to a high-fat diet (HFD) and exposing human umbilical vein endothelial cells (HUVECs) to oxidized low-density lipoprotein (ox-LDL), respectively. RESULTS: Our results showed that similar to atorvastatin, SalA suppressed atherosclerotic plaque formation, improved serum lipid accumulation, and reduced cholesterol levels in HFD-fed ApoE-/- mice. Moreover, SalA protected HUVECs from ox-LDL-caused cell viability reduction and lipid accumulation. The mechanism study revealed that SalA reduced the production of proinflammatory cytokines tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, and IL-6, and augmented the generation of the anti-inflammatory cytokine IL-10 in ApoE-/- mice and HUVECs, accompanied by increased HMGCR ubiquitination and degradation via translocation in renal carcinoma on chromosome 8 (Trc8), insulin-induced gene (Insig)1 and Insig2. Furthermore, the knockdown of Trc8 abolished the SalA-induced HMGCR degradation and anti-atherosclerosis activity. CONCLUSION: SalA rescues atherosclerosis by inhibiting inflammation through the Trc8-regulated degradation of HMGCR. These findings underscore Trc8 as a potential target of atherosclerosis.

Agrimol B inhibits colon carcinoma progression by blocking mitochondrial function through the PGC-1α/NRF1/TFAM signaling pathway.

Background: The activation of peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) stimulates the transcription of the downstream target proteins, mitochondrial transcription factor A (TFAM) and nuclear respiratory factor 1 (NRF1), which induces mitochondrial biogenesis and promotes colorectal tumorigenesis. Agrimol B (Agr) is a constituent of Agrimonia pilosa Ledeb. that exerts anticancer effects. Herein, we aimed to investigate the antitumor activity of Agr and its mechanism of action. Methods: The interaction between Agr and PGC-1α was predicted by molecular docking. After the treatment with different concentrations of Agr (0, 144, 288, and 576 nM), the cell viability, migration rate, proliferation rate, and apoptosis rate of human colon cancer HCT116 cells were determined. Mitochondrial activity, cellular reactive oxygen species (ROS), and mitochondrial membrane potential were assessed to measure the regulatory effect of Agr on mitochondrial function. Western blotting (WB) assay was used to examine the expression of PGC-1α, NRF1, and TFAM, as well as of the pro-apoptotic proteins, Bax and Caspase-3, and the antiapoptotic protein (Bcl-2). Finally, subcutaneous tumor xenograft model mice were used to evaluate the effect of Agr on colorectal cancer (CRC) in vivo. Results: The molecular docking results revealed a high likelihood of Agr interacting with PGC-1α. Agr inhibited the proliferation and migration of HCT116 cells, promoted ROS production and mitochondrial oxidative stress, inhibited mitochondrial activity, and decreased mitochondrial membrane potential. Agr induced cell apoptosis and, in combination with PGC-1α, impaired mitochondrial biogenesis and suppressed the expression of NRF1 and TFAM. Agr also suppressed the expression of Bcl-2 and Cleaved-Caspase-3 and increased the expression of Bax and Caspase-3. In addition, the in vivo antitumor effect and mechanism of Agr were confirmed by using a subcutaneous tumor xenograft mouse model. Conclusions: Our findings demonstrated that Agr regulates the expression of PGC-1α, thereby inducing mitochondrial dysfunction and promoting tumor cell apoptosis. This work highlights the potential of Agr as a promising therapeutic candidate in CRC.