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Background: Anticonvulsants are drugs used in the treatment of seizures; their pharmacology includes promoters of brain inhibition and inhibitors of brain activity. Of the latter, voltagedependent sodium channel blockers (VGSCB) are the most widely used in therapeutics. Objective: The study aimed at proposing the structural requirements of VGSC blockers through a quantitative structure-activity relationship analysis of drugs with proven activity. Methods: IC50 values of anticonvulsant drugs on VGSCs were considered under similar experimental conditions; some physicochemical properties of the molecules that were correlated with their biological activity were determined in silico. Results: Relationships were observed between the dipole moment, pKa, EHOMO, and MR with the biological activity, which infers that between greater polarity and basicity of the drugs, their activity as blockers will increase. Subsequently, the structural subclassification of the drugs was carried out, based on the urea derivation, the groups of which were: Group 1 (direct and bioisostere derivatives) and Group 2 (homologue and vinylogue derivatives of urea). Conclusion: The biological activity depends on the polarity, basicity, and electronic density of the drugs. The derivation of urea is essential, which is present in its original substituted form or a bioisosteric form. Urea can be in the form of a homologue or a vinylogue at the ends of the molecule. Aromatic substitution to the urea portion is necessary.

Inorganic arsenic (iAs) exposure is a serious health problem that affects more than 140 million individuals worldwide, mainly, through contaminated drinking water. Acute iAs poisoning produces several symptoms such as nausea, vomiting, abdominal pain, and severe diarrhea, whereas prolonged iAs exposure increased the risk of several malignant disorders such as lung, urinary tract, and skin tumors. Another sensitive endpoint less described of chronic iAs exposure are the non-malignant health effects in hepatic, endocrine, renal, neurological, hematological, immune, and cardiovascular systems. The present review outlines epidemiology evidence and possible molecular mechanisms associated with iAs-toxicity in several non-carcinogenic disorders.

Diabetes mellitus (DM) is a chronic metabolic disorder characterized by impaired glucose homeostasis, insulin resistance and hyperglycemia. Among its serious multisystemic complications is diabetic retinopathy (DR), which develops slowly and often insidiously. This disorder-the most common cause of vision loss in working-age adults-is characterized by functional and morphological changes in the retina. It results from the exacerbation of ischemic and inflammatory conditions prompted by alterations in the blood vessels, such as the development of leukostasis, thickening of the basement membrane, retinal neovascularization and fibrovascular tissue formation at the vitreoretinal interface. The pathogenic alterations are usually triggered at the biochemical level, involving a greater activity in 4 pathways: the polyol pathway, the hexosamine pathway, the formation of advanced glycation end-products and the activation of protein kinase C isoforms. When acting together, these pathways give rise to increased levels of reactive oxygen species and decreased levels of endogenous antioxidant agents, thus generating oxidative stress. All current therapies are aimed at the later stages of DR, and their application implies side effects. One possible strategy for preventing the complications of DM is to counteract the elevated superoxide production stemming from a high level of blood glucose. Accordingly, some treatments are under study for their capacity to reduce vascular leakage and avoid retinal ischemia, retinal neovascularization and macular edema. The present review summarizes the biochemical aspects of DR and the main approaches for treating it.

Arsenic, a metalloid and naturally occurring element, is one of the most abundant elements in the earth's crust. Water is contaminated by arsenic through natural sources (underground water, minerals and geothermal processes) and anthropogenic sources such as mining, industrial processes, and the production and use of pesticides. Humans are exposed to arsenic mainly by drinking contaminated water, and secondarily through inhalation and skin contact. Arsenic exposure is associated with the development of vascular disease, including stroke, ischemic heart disease and peripheral vascular disease. Also, arsenic increases the risk of tumors of bladder, lungs, kidneys and liver, according to the International Agency for Research on Cancer and the Food and Drug Administration. Once ingested, an estimated 70-90% of inorganic arsenic is absorbed by the gastrointestinal tract and widely distributed through the blood to different organs, primarily to the liver, kidneys, lungs and bladder and secondarily to muscle and nerve tissue. Arsenic accumulates in the organs, especially in the liver. Its excretion mostly takes place through urination. The toxicokinetics of arsenic depends on the duration of exposure, pathway of ingestion, physicochemical characteristics of the compound, and affected biological species. The present review outlines of arsenic toxic effects focusing on different cancer types whit highest prevalence's by exposure to this metalloid and signaling pathways of carcinogenesis.

Aims To evaluate the effects of (-)-epicatechin (Epi) in the progression of kidney damage. Material and methods We assessed the effects of Epi [0.01–20 mg/kg of body weight/day] during 14 days, in a 5/6 nephrectomy model in mice. Key findings Nephrectomy-induced systolic arterial hypertension was significantly reduced in a dose dependent manner with Epi treatment. Increased serum creatinine and urea were reduced almost to normal values. The concentration of tetrahydrobiopterin (BH4), used as subrogate of endothelial dysfunction, decreased in nephrectomyzed animals, Epi treatment increased BH4 levels almost reaching normal values. The expression of angiotensin II receptor (AT1-R) and NADPH oxidase-4 (NOX-4) and 3-nitrotyrosine levels increased with nephrectomy and were reduced with Epi treatment. Renal tissue morphology in the remaining tissue was conserved with Epi treatment in a dose dependent manner. Significance. Chronic kidney disease (CKD) is an independent cardiovascular risk factor associated with a mortality rate 10 to 20 times higher than that of the general population. High blood pressure, endothelial dysfunction and oxidative stress are important factors determining kidney damage progression. Findings of this study indicate that Epi is able to counteract the deleterious effects of subtotal nephrectomy and the structural and functional changes in the remnant kidney tissue, decreasing the progression of CKD. These results warrant the possibility of implement clinical trials to limit the progression of CKD in humans.

Type 2 diabetes (T2D), which causes many adverse effects such as endothelial dysfunction and cardiovascular disease, affects approximately 425 million people worldwide. However, about half have not yet been diagnosed. For what is recommended the use of screening tools to identify individuals at risk for T2D or in the early stages of the disease in order to impement preventive strategies or early treatment. According to a widely used survey, the FINDRISC scale, a hereditary family history of T2D (FH-T2D) is as important a risk factor as having had high glucose levels. The aim of the present study was to carry out non-probabilistic sampling in a Mexican population to evaluate key factors in the development of diabetes. The participants were divided into three groups: with and without FH-T2D and diagnosed with T2D. A comparison of the groups with and without FH-T2D revealed higher values in the former for body mass index (BMI: 24.5 vs 21.9 kg/m2), glycosylated hemoglobin [Hb1Ac: 5.775% (39 mmol/mol) vs 4.825% (29 mmol/mol)] and triglycerides (164.18 vs 68.12 mg/dL), and a lower value for the BH4/BH2 index (0.7846 vs 1.6117). These results indicate significant metabolic alterations and endothelial dysfunction for the FH-T2D group. This strongly suggests the need to screen individuals with a family history of inherited T2D based on their level of HbA1c, triglycerides and BH4.

An increase in the generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS) leads to complications during chronic kidney disease (CKD). This increase essentially derives from the impairment of natural antioxidant systems of the organism. The resulting oxidative stress produces damage to kidney tissue, especially by affecting nephrons and more generally by disrupting the function and structure of the glomerulus and interstitial tubule. This leads to a rapid decline in the condition of the patient and finally renal failure. Possible causes of kidney tissue damage are explored, as are different therapies, especially those related to the administration of antioxidants.

This work was performed to study the effect of allicin on hypertension and cardiac function in a rat model of CKD. The groups were control, CKD (5/6 nephrectomy), and CKD-allicin treated (CKDA) (40 mg/kg day/p.o.). Blood pressure was monitored (weekly/6 weeks). The cardiac function, vascular response to angiotensin II, oxidative stress, and heart morphometric parameters were determined. The CKD group showed hypertension and proteinuria. The coronary perfusion and left ventricular pressures were decreased in CKD group. In contrast, the vascular response to angiotensin II and expression of angiotensin II type 1 receptor (AT1R) were increased. These data were associated with the increment in morphometric parameters (weight of heart and left ventricle, heart/BW and left ventricular mass index, and wall thickness). Concurrently, the oxidative stress was increased and correlated inversely with the expression of Nrf2, Keap1, and antioxidant enzymes Nrf2-regulated. Allicin treatment attenuated hypertension and improved the renal and the cardiac dysfunctions; furthermore, it decreased the vascular reactivity to angiotensin II, AT1R overexpression, and preserved morphometric parameters. Allicin also downregulated Keap1 and increased Nrf2 expression, upregulated the antioxidant enzymes, and reduced oxidative stress. In conclusion, allicin showed an antihypertensive, nephroprotective, cardioprotective, and antioxidant effects, likely through downregulation of AT1R and Keap1 expression.

In this study, 1-(4-di-hydroxy-3,5-dioxa-4-borabicyclo[4.4.0]deca-7,9,11-trien-9-yl)-2-(tert-butylamino)ethanol, (BR-AEA), was designed, synthesized, characterized and tested in docking studies and in vitro. Previous to its synthesis, a set of compounds, including well-known ligands and boron containing compounds, were studied under docking simulations. BR-AEA showed greater affinity than these well-known agonists and was found to be slightly closer than salbutamol to the residues in the TM5 and TM3 of the beta(2) adrenoceptor (beta(2)AR), making a greater number of interactions with them, including some that are apparently key to greater affinity and beta(2)AR activation. This study suggests that affinity is closely related to the interactions of the boron atom, as well as the capacity of boronic acid moieties to make a network of hydrogen bonds with the beta(2)AR. In vitro, the relaxing effects of BR-AEA on isolated guinea pig tracheal rings were compared with salbutamol. The EC(50) values for BR-AEA were at least five-fold lower than for salbutamol, showing the greater potency of the former. Additionally, propranolol and ICI 118,551 showed competitive antagonism in relation to the relaxing effect of the test compound (pA(2) 6.204+/-0.367 and 9.089+/-0.470, respectively).

SUMMARY: Aim Reduction in nitric oxide (NO) levels during kidney failure has been related to the reaction of NO with superoxide anions to yield peroxynitrite which possesses the biological activity responsible for renal damage. However, stimulation of the NO pathway ameliorates the progression of kidney failure. Thus, it is unclear whether NO prevents or acts as the compound responsible for the cytotoxicity observed during kidney failure. Methods We evaluated the development of kidney failure in animals that were wild type and deficient in endothelial NO synthase (eNOS (−/−)) and tested the effects of an antioxidant treatment and NO precursors on the generation of superoxide anion and kidney failure parameters. Results In wild-type mice, five-sixths nephrectomy increased proteinuria from 3.0 ± 0.35 to 14.5 ± 0.76 mg protein/24 h (P

Peripheral arterial occlusive disease (PAD) describes vascular disorders associated with ischemia and PAD affects about 8 million people in the United States. Moreover, PAD's prevalence can increase dramatically if cardiovascular disease is present. In healthy individuals reducing blood flow through the lower extremity is followed by a physiological process to limit ischemia in the distal tissue. This process is called revascularization and impairing revascularization results in PAD. Studies suggest nitric oxide (NO) maybe involved in the ischemia-dependent hindlimb revascularization process. NO is increased in the ischemic hindlimb and eliminating NO impairs the revascularization process. Moreover, restoring NO improves hindlimb revascularization. NO may be acting through its effects on vascular tone, cell migration, or extracellular matrix degradation. The present review illustrates nitric oxide's critical role in the ischemia-induced hindlimb revascularization. Thus, restoring normal NO levels in diseased arteries may represent a viable therapeutic avenue by supplementing exogenous NO or employing therapeutic strategies to either increase NO synthesis and its messengers or decrease NO catabolism.

Obesity is a worldwide epidemic that is characterized not only by excessive fat deposition but also by systemic microinflammation, high oxidative stress, and increased cardiovascular risk factors. While diets enriched in natural antioxidants showed beneficial effects on oxidative stress, blood pressure, and serum lipid composition, diet supplementation with synthetic antioxidants showed contradictive results. Thus, we tested in C57Bl/6 mice whether a daily dosage of an antioxidative mixture consisting of vitamin C, vitamin E, L-arginine, eicosapentaenoic acid, and docosahexaenoic acid (corabion) would affect cardiovascular risk factors associated with obesity. Obese mice showed increased serum triglyceride and glucose levels and hypertension after eight weeks of being fed a high-fat diet (HFD). Importantly, corabion ameliorated all of these symptoms significantly. Oxidative stress and early signs of systemic microinflammation already developed after two weeks of high-fat diet and were significantly reduced by daily doses of corabion. Of note, the beneficial effects of corabion could not be observed when applying its single antioxidative components suggesting that a combination of various nutrients is required to counteract HFD-induced cardiovascular risk factors. Thus, daily consumption of corabion may be beneficial for the management of obesity-related cardiovascular complications.

The density of Angiotensin II (Ang) receptors on tissue surfaces is regulated by multiple hormones, cytokines and metabolic factors and is profoundly affected by various pathological conditions, such as age, diet and environmental conditions. The participation of several cardiovascular risk factors in the regulation of Angiotensin II receptor expression has been incompletely studied. We performed an ex-vivo study with human aortic postsurgical specimens to test the hypothesis that Ang AT1 and AT2 receptor expression in human aortic arteries is associated with the presence of cardiovascular risk factors. We included 31 Mexican patients with coronary artery disease. We evaluated Angiotensin II receptor expression by immunostaining and angiotensin converting enzyme insertion/deletion (ACE I/D) polymorphisms by polymerase chain reaction. AT1 and AT2 receptor expression was increased in the aortic segments from the cardiovascular patients compared with control arteries and in patients with the DD genotype. There was a correlation between increased AT1 receptor expression and the number of cardiovascular risk factors present in the patient. Furthermore, reduction of AT1 expression correlated with the number of drug combinations used in the patients. These correlations were not present with respect to AT2 receptor expression. We suggest that increased AT1 receptor expression is associated with the DD genotype. Thus the presence of several cardiovascular risk factors as well as DD genotype, induce AT1 expression increasing the probability to develop coronary occlusive disease.

The increase of reactive oxygen species (ROS) in diabetes potentiates the vascular effects of phenylephrine through nitric oxide (NO) impairment, facilitating the development of diabetic nephropathy. We propose that the combination of an antioxidant and L-arginine as diet supplements could prevent the increased vascular response to phenylephrine in diabetic animals.Changes in the adrenergic system play an important role in the development of vascular complications in the prediabetic condition. The vasoconstrictor effects of phenylephrine are regulated by NO, and the impairment of endothelium-dependent vasodilation in diabetes is associated with ROS.Diabetes was induced with a low dose (55 mg/kg body weight) of streptozotocin in 7-week-old rats. Diabetic rats were fed with a diet supplement containing a combination of vitamin E, vitamin C, eicosapentaenoic acid, docosahexaenoic acid, and L-arginine, and the effects on phenylephrine-induced renal vascular responses were evaluated.Phenylephrine increased the renal perfusion pressure of isolated perfused kidneys from diabetic rats compared with nondiabetic rats. This effect was associated with reduced nitrite release as well as reduced plasma tetrahydrobiopterin and increased superoxide anions in the renal tissue. Diet supplementation with a combination of L-arginine and vitamins in diabetic rats partially prevented the generation of superoxide associated with recovery of the renal release of NO and decreased phenylephrine-induced vasoconstrictor effects, compared with untreated diabetic rats. However, the administration of L-arginine or vitamins alone did not affect phenylephrine-induced vasoconstriction. Vitamin treatment alone did decrease superoxide generation.The protective mechanism of NO on the vasoconstrictor effects of phenylephrine in the kidney is lost during the development of diabetes, probably via the actions of ROS through a decrease in tetrahydrobiopterin, thus contributing to the pathogenesis of diabetic nephropathy. Restoration of this protective NO mechanism can be achieved by simultaneously stimulating NO synthesis and preventing the effects of ROS through the use of L-arginine and a combination of vitamins E and C as diet supplementation.