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Five new steroidal glycosides, named as stauntosides D 1 ( 1 ), D 2 ( 2 ), D 3 ( 3 ), I 1 ( 4 ), and I 2 ( 5 ), were isolated from the 95% ethanol extract of the roots of Cynanchum stauntonii . Their structures were elucidated by extensive spectroscopic analyses, including 1D, 2D NMR, and HRESI–MS, and qualitative chemical methods. All compounds were tested for cytotoxicity against five human tumor cell lines (HCT-8, Bel-7402, BGC-823, A549, and A2780) where they were found to be inactive. Their significance in terms of the chemotaxonomy of C. stauntonii is discussed. [ABSTRACT FROM AUTHOR]

Circadian rhythm disturbance (CRD) is one of the iconic manifestations in Alzheimer’s disease (AD), a disease tightly associated with age, but the characteristics and gender difference of CRD occurred in AD have not been well demonstrated. Using 6-month-old triple transgenic AD mouse model (3xTg-AD) without obvious brain pathological changes, we demonstrated the gender difference of CRD at this age. We further showed abnormal Per gene expression in the central clock suprachiasmatic nucleus (SCN) of the 3xTg-AD mice. Specifically, compared with the wide type (WT) mice, the 3xTg-AD mice showed disrupted circadian locomotor rhythms both at LD (light-dark 12 h:12 h) and DD (constant dark) conditions, such as increased activities in the resting phase, decreased and scattered activities in the active phase, decreased overall activity intensities, amplitude, robustness, and increased intradaily variability. We further observed that 3xTg-AD female mice showed obviously less CRD compared with the 3xTg-AD male mice, and female mice of both WT and 3xTg-AD were more active in locomotor activity. Accordingly, 3xTg-AD mice showed a phase delay in the expression of Per1 and Per2 mRNA in the SCN, with the levels of Per1 and Per2 mRNA were significantly lower than that of WT mice at specific time points. We conclude that 3xTg-AD mice exhibit behavioral CRD at the age of six months with male gender preference, and these phenomena are at least partly associated with the alteration of Per1 and Per2 transcription patterns in the SCN. [ABSTRACT FROM AUTHOR]

Diallyl trisulfide (DATS), a natural agent derived from garlic, has been tested for its antigastric cancer activities in various preliminary studies. However, more systematic pharmacodymatic (PD) and mechanistic evaluations are clearly needed. The aim of this study was to investigate the antitumor effects of DATS in the treatment of human gastric cancer cell SGC-7901 both in vitro and in vivo using widely recommended study procedures. DATS suppressed cancer cells proliferation and induced cell cycle arrest accompanied by an increase in the expressions of cyclin A2 and cyclin B1 in SGC-7901 cancer cells. DATS also caused an increase in apoptotic cell death, which involved in accumulations of bax, p53, and cytochrome C and reduction of Bcl-2 expressions. Besides, activation of JNK, ERK and p38 phosphorylation in DATS-treated cells suggested that mitogen-activated protein kinase (MAPKs) pathways were involved in DATS-induced apoptosis. Meanwhile, DATS significantly inhibited tumor growth and promoted tumor apoptosis in a xenograft model of gastric cancer cell SGC-7901. DATS inhibited tumor migration and invasion by modulating MMP9 and E-cadherin protein expressions. In addition, DATS treatment evidently increased the cytokine secretions of IL-12, TNF-α and IFN-γ (p < 0.05). Biochemical serum analysis and histopathological examination indicated no obvious side effects in major mouse organs. Therefore, our findings provide a framework for further exploration of DATS as a novel chemotherapeutic for human gastric cancer. [ABSTRACT FROM AUTHOR]

The anti -cancer effects of oil-soluble organosulfur compounds in garlic in the initiation phase of carcinogenesis are known. However, there are few experimental studies investigating S -allylmercaptocysteine (SAMC), a water-soluble derivative of garlic. This study investigated whether SAMC prevented the carcinogen benzo(a)pyrene (B(a)P) from inducing precancerous activity in human lung cells (A549 cell line). A549 cells were either pre-treated (PreTM) or concurrently treated (CoTM) with 1 μM B(a)P and either 10 or 50 μM SAMC. The 50 μM PreTM group inhibited B(a)P-induced cell proliferation by approximately 100%. The 50 μM SAMC PreTM and CoTM inhibited the B(a)P-induced G2/M phase shift by 100% and 97%, respectively. Furthermore, the PreTM and CoTM groups exhibited the potential to reduce the generation of reactive oxygen species (ROS) relative to the B(a)P group by at least 78%. The SAMC PreTM elevated superoxide dismutase (SOD) by approximately 100%. In this study, we revealed the mechanisms involved in SAMC inhibition of B(a)P-induced carcinogenesis, including suppression of cell proliferation, cell cycle regulation, attenuation of ROS formation, inhibition of DNA damage, increase of SOD activity and inhibition of nuclear factor-kappa B (NF-κB) activity. SAMC appears to be a novel therapeutic candidate for the prevention and treatment of B(a)P-induced human lung cancer. [ABSTRACT FROM AUTHOR]

Diallyl trisulfide (DATS) is a garlic organosulfide that may have a therapeutic potential in the treatment of some diseases. We sought to determine whether DATS could inhibit naphthalene-induced oxidative injury and the production of inflammatory responses in vitro and in vivo. A549 cells were either pre-treated (PreTx, prevention) or concurrently treated (CoTx, treatment) with 20 μM naphthalene and either 5 or 10 μM DATS. PreTx and CoTx showed the prevention and the treatment potential of DATS to inhibit the generation of naphthalene-induced reactive oxygen species (ROS) in the A549 cells. DATS showed antioxidative activity by elevating the SOD activities in the low dose groups. The mechanistic study showed that the DATS-mediated inhibition of naphthalene-induced oxidative injury and the production of inflammatory responses (i.e., TNF-α, IL-6, and IL-8) were attributed to inhibiting the activity of nuclear factor-kappa B (NF-κB). In addition, DATS inhibited the production of serum nitric oxide NO and myeloperoxidase (MPO) in the lungs of Kunming mice. The histological analysis results indicate that DATS inhibited the naphthalene-induced lung damage, which is consistent with the in vitro study results. The in vivo and in vitro results suggest that DATS may be an effective attenuator of naphthalene-induced lung damage. [ABSTRACT FROM AUTHOR]

[Display omitted] The repair of vascular endothelial cell dysfunction is an encouraging approach for the treatment of vascular complications associated with diabetes. It has been demonstrated that members of C1q/tumor necrosis factor-related protein (CTRP) family may improve endothelial function. Nevertheless, the protective properties of CTRPs in diabetic microvascular complications continue to be mostly unknown. Here, we demonstrate that the C1q-like globular domain of CTRP3, CTRP5, and CTRP9 (gCTRP3, 5, 9) exerted a vasorelaxant effect on the microvasculature, of which gCTRP3 was the most powerful one. In a murine model of type 2 diabetes mellitus, serum gCTRP3 level and endothelial function decreased markedly compared with controls. Two weeks of gCTRP3 treatment (0.5 μg/g/d) enhanced endothelium-dependent relaxation in microvessels, increased nitric oxide (NO·) production, and reduced retinal vascular leakage. In addition, Western blotting in human retinal microvascular endothelial cells indicated that gCTRP3 triggered AMP-activated protein kinase-α (AMPKα), hence increasing the endothelial NO synthase (eNOS) level and NO· production. In addition, incubation with gCTRP3 in vitro ameliorated the endothelial dysfunction induced by high glucose in the branch of the mesenteric artery. Blockade of either eNOS or AMPKα completely abolished the effects of gCTRP3 described above. Taken together, we demonstrate for the first time that gCTRP3 improves impaired vasodilatation of microvasculature in diabetes by ameliorating endothelial cell function through the AMPK/eNOS/NO· signaling pathway. This finding may suggest an effective intervention against diabetes-associated microvascular complications. [ABSTRACT FROM AUTHOR]

Atherosclerotic vascular disease remains the principal cause of death and disability among patients with type 2 diabetes. Unfortunately, the problem is not adequately resolved by therapeutic strategies with currently available drugs or approaches that solely focus on optimal glycemic control. To identify the key contributors and better understand the mechanism of diabetic atherosclerotic vascular disease, we aimed to elucidate the key genetic characteristics and pathological pathways in atherosclerotic vascular disease through nonbiased bioinformatics analysis and subsequent experimental demonstration and exploration in diabetic atherosclerotic vascular disease. Sixty-eight upregulated and 23 downregulated genes were identified from the analysis of gene expression profiles (GSE30169 and GSE6584). A comprehensive bioinformatic assay further identified that ferroptosis, a new type of programmed cell death and HMOX1 (a gene that encodes heme oxygenase), were vital factors in atherosclerotic vascular disease. We further demonstrated that diabetes significantly increased ferroptosis and HMOX1 levels compared to normal controls. Importantly, the ferroptosis inhibitor ferrostatin-1 (Fer-1) effectively attenuated diabetic atherosclerosis, suggesting the causative role of ferroptosis in diabetic atherosclerosis development. At the cellular level, Fer-1 ameliorated high glucose high lipid-induced lipid peroxidation and downregulated ROS production. More importantly, HMOX1 knockdown attenuated Fe2+ overload, reduced iron content and ROS, and alleviated lipid peroxidation, which led to a reduction in ferroptosis in diabetic human endothelial cells. We demonstrated that HMOX1 upregulation is responsible for the increased ferroptosis in diabetic atherosclerosis development, suggesting that HMOX1 may serve as a potential therapeutic or drug development target for diabetic atherosclerosis. [ABSTRACT FROM AUTHOR]

Since an outbreak of vaping-related deaths in the US has been reported as a public health crisis, the cardiovascular safety of nicotine nowadays receives increasing attention due to use of tobacco cigarette alternatives, such as electronic cigarettes. However, whether and how nicotine contributes to cardiac detrimental effects are in great controversy, especially less understood in young adult population. We report that chronic nicotine exposure, a major component of Electronic cigarettes, resulted in directly inhibited cardiomyocytes viability, increased cardiac fibrosis, and markedly suppressed cardiac function compared with sham. Gene array combined with bioinformatics analysis identified cardiac apoptosis and mitophagy were the key signals responsible for nicotine induced cardiac detrimental effect. Mechanistically, nicotine exposure markedly increased cleaved Caspase 3 and cleaved Caspase 9 indicating the involvement of intrinsic apoptotic pathway (mitochondrial cell death pathway). Meanwhile, nicotine-induced ROS outbreak promoted lysomal alkalization, furthermore blocked mitophagic degradation, thereby disrupted mitophagic flux promoted mitochondrial cell death cascade. Taken together, these findings indicate that nicotine confers cardiotoxicity via ROS-induced mitophagic flux blockage and provide the first demonstration of a causative link between nicotine and cardiac toxicity in young adult rat which may suggest nicotine induces cardiomyocytes impairment leading to cardiotoxicity in young adult population. [ABSTRACT FROM AUTHOR]

Arrhythmogenesis of chronic myocardial infarction (MI) is associated with the prolongation of action potential, reduction of inward rectifier potassium (I K1 , Kir) channels and hyper-activity of Calcium/calmodulin-dependent kinase II (CaMKII) in cardiomyocytes. Zacopride, a selective I K1 agonist, was applied to clarify the cardioprotection of I K1 agonism via a CaMKII signaling on arrhythmias post-MI. Male SD rats were implanted wireless transmitter in the abdominal cavity and subjected to left main coronary artery ligation or sham operation. The telemetric ECGs were monitored per day throughout 4 weeks. At the endpoint, isoproterenol (1.28 mg/kg, i.v.) was administered for provocation test. The expressions of Kir2.1 (dominant subunit of I K1 in ventricle) and CaMKII were detected by Western-blotting. In the telemetric rats post-MI, zacopride significantly reduced the episodes of atrioventricular conduction block (AVB), premature ventricular contraction (PVC), ventricular tachycardia (VT) and ventricular fibrillation (VF), without significant effect on superventricular premature contraction (SPVC). In provocation test, zacopride suppressed the onset of ventricular arrhythmias in conscious PMI or sham rats. The expression of Kir2.1 was significantly downregulated and p -CaMKII was upregulated post-MI, whereas both were restored by zacopride treatment. I K1 /Kir2.1 might be an attractive target for pharmacological controlling of lethal arrhythmias post MI. [ABSTRACT FROM AUTHOR]