N′-(3-Phenyl­allyl­idene)nicotinohydrazide monohydrate

In the title compound, C15H13N3O·H2O, the dihedral angle between the pyridine and phenyl rings is 35.45 (7)°. Inter­molecular O—H⋯O, O—H⋯N, N—H⋯O and C—H⋯O hydrogen bonds are found in the crystal structure. In addition, C—H⋯π inter­actions involving the pyridine and phenyl rings are also found

N′-(2-Methyl-3-phenyl­allyl­idene)nicotinohydrazide monohydrate

The asymmetric unit of the title compound, C16H15N3O·H2O, contains an N′-(2-methyl-3-phenyl­allyl­idene)nicotino­hydra­zide mol­ecule and a water solvent mol­ecule. The dihedral angle between the pyridine ring and the phenyl ring is 47.26 (5)°. Inter­molecular O—H⋯N, O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds are found in the crystal structure. Furthermore, C—H⋯π inter­actions involving the pyridine and phenyl rings are also found

Role of Dietary Antioxidants in the Preservation of Vascular Function and the Modulation of Health and Disease

In vascular diseases, including hypertension and atherosclerosis, vascular endothelial dysfunction (VED) occurs secondary to altered function of endothelial nitric oxide synthase (eNOS). A novel redox regulated pathway was identified through which eNOS is uncoupled due to S-glutathionylation of critical cysteine residues, resulting in superoxide free radical formation instead of the vasodilator molecule, nitric oxide. In addition, the redox sensitive cofactor tetrahydrobiopterin, BH4, is also essential for eNOS coupling. Antioxidants, either individually or combined, can modulate eNOS uncoupling by scavenging free radicals or impairing specific radical generating pathways, thus preventing oxidative stress and ameliorating VED. Epidemiological evidence and dietary guidelines suggest that diets high in antioxidants, or antioxidant supplementation, could preserve vascular health and prevent cardiovascular diseases (CVDs). Therefore, the purpose of this review is to highlight the possible role of dietary antioxidants in regulating eNOS function and uncoupling which is critical for maintenance of vascular health with normal blood flow/circulation and prevention of VED. We hypothesize that a conditioned dietary approach with suitable antioxidants may limit systemic oxidation, maintain a beneficial ratio of reduced to oxidized glutathione, and other redox markers, and minimize eNOS uncoupling serving to prevent CVD and possibly other chronic diseases

Targeting the Nrf2/ARE Signalling Pathway to Mitigate Isoproterenol-Induced Cardiac Hypertrophy: Plausible Role of Hesperetin in Redox Homeostasis

Cardiac hypertrophy is the underlying cause of heart failure and is characterized by excessive oxidative stress leading to collagen deposition. Therefore, understanding the signalling mechanisms involved in excessive extracellular matrix deposition is necessary to prevent cardiac remodelling and heart failure. In this study, we hypothesized that hesperetin, a flavanone that elicits the activation of Nrf2 signalling and thereby suppresses oxidative stress, mediated pathological cardiac hypertrophy progression. A cardiac hypertrophy model was established with subcutaneous injection of isoproterenol in male Wistar rats. Oxidative stress markers, antioxidant defense status, and its upstream signalling molecules were evaluated to discover the impacts of hesperetin in ameliorating cardiac hypertrophy. Our results implicate that hesperetin pretreatment resulted in the mitigation of oxidative stress by upregulating antioxidant capacity of the heart. This curative effect might be owing to the activation of the master regulator of antioxidant defense system, known as Nrf2. Further, analysis of Nrf2 revealed that hesperetin enhances its nuclear translocation as well as the expression of its downstream targets (GCLC, NQO1, and HO-1) to boost the antioxidative status of the cells. To support this notion, in vitro studies were carried out in isoproterenol-treated H9c2 cells. Immunocytochemical analysis showed augmented nuclear localization of Nrf2 implicating the action of hesperetin at the molecular level to maintain the cellular redox homeostasis. Thus, it is conceivable that hesperetin could be a potential therapeutic candidate that enhances Nrf2 signalling and thereby ameliorates pathological cardiac remodelling

Chronic cigarette smoking causes hypertension, increased oxidative stress, impaired NO bioavailability, endothelial dysfunction, and cardiac remodeling in mice

Cigarette smoking is a major independent risk factor for cardiovascular disease. While the association between chronic smoking and cardiovascular disease is well established, the underlying mechanisms are incompletely understood, partly due to the lack of adequate in vivo animal models. Here, we report a mouse model of chronic smoking-induced cardiovascular pathology. Male C57BL/6J mice were exposed to whole body mainstream cigarette smoke (CS) using a SCIREQ “InExpose” smoking system (48 min/day, 5 days/wk) for 16 or 32 wk. Age-matched, air-exposed mice served as nonsmoking controls. Blood pressure was measured, and cardiac MRI was performed. In vitro vascular ring and isolated heart experiments were performed to measure vascular reactivity and cardiac function. Blood from control and smoking mice was studied for the nitric oxide (NO) decay rate and reactive oxygen species (ROS) generation. With 32 wk of CS exposure, mice had significantly less body weight gain and markedly higher blood pressure. At 32 wk of CS exposure, ACh-induced vasorelaxation was significantly shifted to the right and downward, left ventricular mass was significantly larger along with an increased heart-to-body weight ratio, in vitro cardiac function tended to be impaired with high afterload, white blood cells had significantly higher ROS generation, and the blood NO decay rate was significantly faster. Thus, smoking led to blunted weight gain, hypertension, endothelial dysfunction, leukocyte activation with ROS generation, decreased NO bioavailability, and mild cardiac hypertrophy in mice that were not otherwise predisposed to disease. This mouse model is a useful tool to enable further elucidation of the molecular and cellular mechanisms of smoking-induced cardiovascular diseases