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Atherosclerosis (AS) is a progressive disease of multifactorial origin, which occurs in response to endothelial injury. Increased homocysteine (Hcy) is considered a major cause of endothelial dysfunction, oxidative stress and DNA methylation; however, the mechanisms remain to be fully elucidated. The aim of the present study was to investigate whether Hcy causes injury to endothelial cells (ECs) by the effect of lectin‑like oxidized‑low density lipoprotein receptor‑1 (LOX‑1) DNA methylation through toll‑like receptor 4(TLR4)/nuclear factor (NF)‑κB/DNA methyltransferase (DNMT)1. The ECs were treated with different concentrations of Hcy, and it was found that Hcy promoted the expression of TLR4, leading to EC injury. The effect of oxidative stress was analyzed by measuring superoxide dismutase, malondialdehyde and hydrogen peroxide in the ECs. In addition, the association between NF‑κB and DNMT1 was examined by treatment of the ECs with pyrrolidine dithiocarbamate (PDTC). The results suggested that Hcy induced LOX‑1 DNA hypomethyaltion to promote the expression levels of LOX‑1. Taken together, Hcy injured the ECs through the effect of methylation and trans‑sulfuration metabolism of LOX‑1 through TLR4/NF‑κB/DNMT1. Following injury to the ECs, lipids, particularly ox‑LDL, accumulated in the sub‑endothelial layer to promote the formation of AS.

Aloperine (ALO), one of the alkaloids isolated from Sophora alopecuroides L., is traditionally used for various diseases including neuronal disorders. This study investigated the protective effects of ALO on neonatal rat primary-cultured hippocampal neurons injured by oxygen–glucose deprivation and reperfusion (OGD/RP). Treatment with ALO (25, 50, and 100 mg/l) attenuated neuronal damage (p

Oxysophoridine (OSR) is a major active alkaloid extracted from Sophoraalopecuroides L. The aim of the present study was to investigate the induction of the apoptotic effects of OSR on colorectal cancer cells in vivo and in vitro. The results of the MTT and colony formation assays demonstrated that the proliferation of HCT116 cells was inhibited by OSR in vitro. The characteristics of cellular apoptosis in OSR-treated HCT116 cells were analyzed by Hoechst 33258 staining. It was also observed that the expression of caspase-3, B-cell lymphoma-2 (Bcl-2) associated X protein (Bax) and cytochrome c increased significantly upon OSR treatment. However, the expression of Bcl-2 and poly ADP-ribose polymerase-1 (PARP-1) was downregulated in OSR-treated cells compared with untreated cells. The in vivo experiments identified that OSR significantly inhibited the growth of the transplanted mouse CT26 tumor tissue, upregulated the expression of caspase-3, Bax and cytochrome c and downregulated the expression of Bcl-2 and PARP-1, as detected by reverse transcription-quantitative polymerase chain reaction and western blotting. It may be concluded that OSR significantly induced apoptotic effects on colorectal cancer cells in vivo and in vitro, and that its mechanism may be associated with the Bcl-2/Bax/caspase-3 signaling pathway.

Vascular smooth muscle cell (VSMC) proliferation is a primary pathological event in atherosclerosis (AS), and homocysteine (Hcy) is an independent risk factor for AS. However, the underlying mechanisms are still lagging. Studies have used the combination of methylation of promoters of multiple genes to diagnose tumors, thus the aim of the current study was to investigate the role of methylation status of several genes in VSMCs treated with Hcy. CpG islands were identified in the promoters of platelet‑derived growth factor (PDGF), p53, phosphatase and tensin homologue on chromosome 10 (PTEN) and mitofusin 2 (MFN2). Hypomethylation was observed to occur in the promoter region of PDGF, hypermethylation in p53, PTEN and MFN2, and hypomethylation in two global methylation indicators, aluminium (Alu) and long interspersed nucleotide element‑1 (Line‑1). This was accompanied by an increase in the expression of PDGF, and reductions of p53, PTEN and MFN2, both in mRNA and protein levels. An elevation of S‑adenosylmethionine (SAM) and a reduction of S‑adenosylhomocysteine (SAH) and the SAM/SAH ratio were also identified. In conclusion, Hcy impacted methylation the of AS‑associated genes and global methylation status that mediate the cell proliferation, which may be a character of VSMCs treated with Hcy. The data provided evidence for mechanisms of VSMCs proliferation in AS induced by Hcy and may provide a new perspective for AS induced by Hcy.

Lanthanum, a rare earth element, has been used to decrease serum phosphorus level in patients with chronic renal disease and hyperphosphatemia. We aimed to observe the effect and mechanism of two doses of lanthanum acetate (375 and 750 mg/kg/day) on vascular calcification induced by vitamin D3 plus nicotine treatment in rats for 4 weeks. As compared with control rats, rats with calcification showed widespread calcified nodules and irregular elastic fibers in calcified aorta on von Kossa calcium staining and increased aortic calcium and phosphorus contents, alkaline phosphatase (ALP) activity and bone-related protein expressions for osteopontin (OPN) and type III sodium dependent phosphate cotransporter Pit-1 (Pit-1). After treatment with either dose of lanthanum acetate, the calcified nodules and degree of irregular elastic fibers decreased in aortas. Lanthanum acetate at 750 mg/kg/day was more effective than 375 mg/kg/day in lessening vascular calcification by significantly reducing plasma phosphorus level, calcium × phosphorus product and ALP activity, by 30.3%, 28.6%, and 68.6%, respectively; reducing aortic phosphorus and calcium contents and ALP activity, by 48%, 53.1%, and 63.5% (all P < 0.01), respectively; reducing aortic mRNA level of OPN and Pit-1, by 55.8% ( P < 0.01) and 38.8% ( P < 0.05) and protein level of OPN and Pit-1, by 37.2% and 27.2% (both P < 0.01), respectively; and increasing carboxylated matrix Gla-protein (MGP) protein expression by 33.7% ( P < 0.05), as compared with rats treated with vitamin D3 and nicotine alone. Lanthanum acetate could effectively inhibit the pathogenesis of vascular calcification.

Our previous studies have demonstrated that oxysophoridine (OSR) has protective effects on cerebral neurons damage in vitro induced by oxygen and glucose deprivation. In this study, we further investigated whether OSR could reduce ischemic cerebral injury in vivo and its possible mechanism. Male Institute of cancer research mice were intraperitoneally injected with OSR (62.5, 125 and 250 mg/kg) for seven successive days, then subjected to brain ischemia induced by the model of middle cerebral artery occlusion. After reperfusion, neurological scores and infarct volume were estimated. Morphological examination of tissues was performed. Apoptotic neurons were detected by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling staining. Oxidative stress levels were assessed by measurement of malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels. The expression of various apoptotic markers as Caspase-3, Bax and Bcl-2 were investigated by immunohistochemistry and Western-blot analysis. OSR pretreatment groups significantly reduced infract volume and neurological deficit scores. OSR decreased the percentage of apoptotic neurons, relieved neuronal morphological damage. Moreover, OSR markedly decreased MDA content, and increased SOD, GSH-Px activities. Administration of OSR (250 mg/kg) significantly suppressed overexpression of Caspase-3 and Bax, and increased Bcl-2 expression. These findings indicate that OSR has a protective effect on focal cerebral ischemic injury through antioxidant and anti-apoptotic mechanisms.

Both tyrosine kinase and topoisomerase II (TopII) are important anticancer targets, and their respective inhibitors are widely used in cancer therapy. However, some combinations of anticancer drugs could exhibit mutually antagonistic actions and drug resistance, which further limit their therapeutic efficacy. Here, we report that HMNE3, a novel bis-fluoroquinolone chalcone-like derivative that targets both tyrosine kinase and TopII, induces tumor cell proliferation and growth inhibition. The viabilities of 6 different cancer cell lines treated with a range of HMNE3 doses were detected using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cellular apoptosis was determined using Hoechst 33258 fluorescence staining and the terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) assay. The expression of activated Caspase-3 was examined by immunocytochemistry. The tyrosine kinase activity was measured with a human receptor tyrosine kinase (RTK) detection kit using a horseradish peroxidase (HRP)-conjugated phosphotyrosine (pY20) antibody as the substrate. The topoisomerase II activity was measured using agarose gel electrophoresis with the DNA plasmid pBR322 as the substrate. The expression levels of the P53, Bax, Bcl-2, Caspase-3, -8, -9, p-cSrc, c-Src and topoisomerase II proteins were detected by western blot analysis. The proliferation of five of the six cancer cell lines was significantly inhibited by HMNE3 at 0.312 to 10 μmol/L in a time- and dose-dependent manner. Treatment of the Capan-1 and Panc-1 cells with 1.6 to 3.2 μM HMNE3 for 48 h significantly increased the percentage of apoptotic cells (P