Search results for "NADP"

Cellular mechanisms of IL-17-induced blood-brain barrier disruption.

2009

Recently T-helper 17 (Th17) cells were demonstrated to disrupt the blood-brain barrier (BBB) by the action of IL-17A. The aim of the present study was to examine the mechanisms that underlie IL-17A-induced BBB breakdown. Barrier integrity was analyzed in the murine brain endothelial cell line bEnd.3 by measuring the electrical resistance values using electrical call impedance sensing technology. Furthermore, in-cell Western blots, fluorescence imaging, and monocyte adhesion and transendothelial migration assays were performed. Experimental autoimmune encephalomyelitis (EAE) was induced in C57BL/6 mice. IL-17A induced NADPH oxidase- or xanthine oxidase-dependent reactive oxygen species (ROS)…

Polyoxypregnanes as safe, potent, and specific ABCB1-inhibitory pro-drugs to overcome multidrug resistance in cancer chemotherapy in vitro and in vivo

2021

Multidrug resistance (MDR) mediated by ATP binding cassette subfamily B member 1 (ABCB1) is significantly hindering effective cancer chemotherapy. However, currently, no ABCB1-inhibitory drugs have been approved to treat MDR cancer clinically, mainly due to the inhibitor specificity, toxicity, and drug interactions. Here, we reported that three polyoxypregnanes (POPs) as the most abundant constituents of Marsdenia tenacissima (M. tenacissima) were novel ABCB1-modulatory pro-drugs, which underwent intestinal microbiota-mediated biotransformation in vivo to generate active metabolites. The metabolites at non-toxic concentrations restored chemosensitivity in ABCB1-overexpressing cancer cells v…

Inhibitory effects on mitochondrial complex I of semisynthetic mono-Tetrahydrofuran acetogenin derivatives

2003

Modifications in the terminal alpha,beta-unsaturated gamma-methyl-gamma-lactone moiety or in the alkyl chain that links this terminal gamma-lactone with the alpha,alpha'-dihydroxylated THF system of the natural mono-tetrahydrofuranic acetogenins, annonacin and annonacinone, led to the preparation of eight semisynthetic derivatives. Their inhibitory effects on mitochondrial complex I is discussed and compared with that of the classical complex I inhibitor, rotenone.

Prevalence of methylenetetrahydrofolate reductase 677T and 1298C alleles and folate status: a comparative study in Mexican, West African, and Europea…

2006

Background: Methylenetetrahydrofolate reductase (MTHFR) 677C→T polymorphism is heterogeneously distributed worldwide, with the highest and lowest frequencies of the T allele in Mexico and Africa, respectively, and a south-to-north gradient in Europe. Distribution of MTHFR 1298A→C is less well known. It has been hypothesized that 677T frequency could result in part from gene-nutrient interactions. Objective: The objective was to compare the association of 677T and 1298C alleles with plasma concentrations of homocysteine, folate, and vitamin B-12 in geographical areas with contrasting 677T allele frequencies. Design: Healthy young adults (n = 1:277) were recruited in Mexico City, the West Afr…

Inadequate Cytoplasmic Antioxidant Enzymes Response Contributes to the Oxidative Stress in Human Hypertension

2006

Untreated hypertensive patients show increased oxidative stress and decreased antioxidant enzyme activity in mononuclear cells. Therefore, the objective of this study was to determine whether or not the low antioxidant enzyme activity observed in mononuclear cells of hypertensive subjects is in part dependent on a defective activity of antioxidant mechanisms. Activity and mRNA level of antioxidant enzymes, CuZn- and Mn-superoxide dismutases, catalase, glutathione peroxidase type 1, and glutathione reductase were simultaneously measured in mononuclear cells of controls (n = 38) and hypertensive subjects (n = 35), in the absence of and during antihypertensive treatment. An increase in oxidati…

Cyclooxygenase 2-selective and nonselective nonsteroidal anti-inflammatory drugs induce oxidative stress by up-regulating vascular NADPH oxidases.

2008

Cyclooxygenase 2-selective inhibitors (coxibs) and nonselective nonsteroidal anti-inflammatory drugs (NSAIDs) are associated with an increase in cardiovascular events. The current study was designed to test the effect of coxibs and nonselective NSAIDs on vascular superoxide and nitric oxide (NO) production. mRNA expression of endothelial NO synthase (eNOS) and of the vascular NADPH oxidases was studied in spontaneously hypertensive rats (SHR) and in human endothelial cells. The expression of Nox1, Nox2, Nox4, and p22phox was increased markedly by the nonselective NSAIDs diclofenac or naproxen and moderately by rofecoxib or celecoxib in the aorta and heart of SHR. The up-regulation of NADPH …

Migraine mediates the influence of C677T MTHFR genotypes on ischemic stroke risk with a stroke-subtype effect.

2007

Background and Purpose— The objective was to investigate the role of C677T MTHFR polymorphism in migraine pathogenesis and in the migraine–ischemic stroke pathway. Methods— A first genotype–migraine association study was conducted on 100 patients with migraine with aura (MA), 106 with migraine without aura (MO), and 105 subjects without migraine, which provided evidence in favor of association of the TT677 MTHFR genotype with increased risk of MA compared with both control subjects (OR, 2.48; 95% CI, 1.11 to 5.58) and patients with MO (OR, 2.21; 95% CI, 1.01 to 4.82). Based on these findings, mediational models of the genotype–migraine–stroke pathway were fitted on a group of 106 patients …

Superficial venous thrombosis: Prevalence of common genetic risk factors and their role on spreading to deep veins

2008

Introduction. Superficial venous thrombosis (SVT) has been considered for a long time a limited clinical condition with a low importance, but this approach has changed in recent years, when several studies demonstrated spreading to deep veins occurring from 7.3 to 44%, with high prevalence of pulmonary embolism . Materials and Methods. To evaluate the prevalence of genetic risk factors for VTE in patients suffering from SVT on both normal and varicose vein, and to evaluate their role on spreading to deep veins, we studied 107 consecutive outpatients with symptomatic SVT. Ultrasound examination was performed, and the presence of FV Leiden, Prothrombin G20210A mutation, MTHFR C677T mutation w…

Coexistence of thrombophilic gene polymorphisms among 559 unrelated consecutive patients with a history of thrombosis.

2001

Association of C677T polymorphism in MTHFR gene, high homocysteine and low HDL cholesterol plasma values in heterozygous familial hypercholesterolemi…

2010

Aim: to investigate the association of C677T polymorphism in the methylene tetrahydrofolate reductase (MTHFR) gene, homocysteine plasma values (Hcy), and plasma HDL cholesterol in heterozy-gous familial hypercholesterolemia (hFH).Methods: One hundred and twenty-five hFH subjects were studied. Plasma lipid, lipoprotein, vitamin B12, folic acid and Hcy values were determined. C677T polymorphism in the MTHFR gene was detected by SSCP-PCR. Genetic diagnosis of FH was determined by a three-step protocol using SSCP-PCR, Southern blot, long PCR and automatic sequencing.Results: We found significant differences in plasma HDL-C (CC 1.39±0.34, CT 1.33±0.39 and TT 1.14±0.26 mmol/L, p=0.028) between th…