Genetic toxicology and preliminaryin vivostudies of nitric oxide donor tocopherol analogs as potential new class of antiatherogenic agents

Genetic association between eNOS gene polymorphisms and risk of carotid atherosclerosis : A meta-analysis

BACKGROUND

Endothelial nitric oxide synthase (eNOS) has been reported to be involved in the atherosclerotic process. A number of studies have investigated the association between eNOS gene polymorphisms and the risk of carotid atherosclerosis (CAS). However, the results are conflicting and inconclusive. The aim of this study was to evaluate precisely the association between the eNOS T786C, G894T, and 4a/4b polymorphisms and CAS risk.

MATERIAL AND METHODS

A meta-analysis was carried out by retrieving relevant studies from PubMed, Embase, China National Knowledge Infrastructure (CNKI), and Cochrane databases without a restriction on publication year. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were used to describe the strength of the association with CAS.

RESULTS

Data were obtained from eight case-control studies comprising 2975 cases and 2624 controls. Significant associations were detected between the allelic and recessive models of the eNOS T786C polymorphism (allelic: p = 0.04; OR, 95% CI = 1.57 [1.01, 2.44]; recessive: p = 0.03; OR, 95% CI = 1.53 [1.04, 2.24]), as well as the allelic and dominant models of the eNOS 4a/4b polymorphism, and CAS risk in an Asian subgroup (allelic: p = 0.02; OR, 95% CI = 1.49 [1.07, 2.07]; dominant: p = 0.01; OR, 95% CI = 1.50 [1.09, 2.05]), but not in a Caucasian subgroup (p > 0.05). No association was observed between the eNOS G894T polymorphism and CAS risk (p > 0.05).

CONCLUSION

Our study provides evidence that the allelic and recessive models of the eNOS T786C polymorphism and the allelic and dominant models of the eNOS 4a/4b polymorphism may increase the risk of CAS in Asian populations.

Identification of N-Oxide-Containing Aromatic Heterocycles as Pharmacophores for Rumen Fermentation Modifiers

Different strategies have been used to mitigate greenhouse gas emissions from domesticated ruminants, including the removal of protozoa (defaunation). The objective of the present work was to analyze the potential of different N-oxide-containing aromatic heterocycles with known antiprotozoal activity as rumen-gas-abating agents. Nineteen pure compounds, belonging to seven different N-oxide chemotypes from our chemo-library were studied together with monensin in an in vitro rumen simulation assay. Fermentation profiles, i.e., gas production, pH, and short carboxylic acid concentrations, were compared to an untreated control at 96 h post inoculation. In our study, we investigated whole-ruminal fluid, with and without compound treatments, by NMR spectroscopy focusing on concentrations of the metabolites acetate, propionate, butyrate, and lactate. From data analysis, three of the compounds from different N-oxide chemotypes, including quinoxaline dioxide, benzofuroxan, and methylfuroxan, were able to diminish the production of gases such as monensin with similar gas production lag times for each of them. Additionally, unlike monensin, one methylfuroxan did not decrease the rumen pH during the analyzed incubation time, shifting rumen fermentation to increase the molar concentrations of propionate and butyrate. These facts suggest interesting alternatives as feed supplements to control gas emissions from dairy ruminants.

First Example of Catalytic Synthesis of Difurazanohexahydrohexaazapyrenes and in Vitro Study of Their Antitumor Activity

Catalytic method for synthesis of hexahydrohexaazapyrenes bearing two annelated furazan moieties has been successfully developed. Structures of synthesized hexahydrodioxadecaazadicyclopenta[e,l]pyrenes have been determined on the basis of NMR data using 2D techniques, MALDI TOF/TOF mass spectrometry, and X-ray analysis. Primary screening of hexahydrodioxadecaazadicyclopenta[e,l]pyrenes for cytotoxic activity against the K562, Jurkat, U937, and HeLa tumor cell lines has been performed. Studies on the induction of apoptosis and the effect of the synthesized compounds on the cell cycle have been successfully implemented. The synthesized compounds have been found to induce apoptosis of cancer cells in the K562, Jurkat, U937, and HeLa lines.

Pharmacokinetics and pharmacodynamics of nitric oxide mimetic agents

Drug discovery focusing on NO mimetics has been hamstrung due to its unconventional nature. Central to these challenges is the fact that direct measurement of molecular NO in biological systems is exceedingly difficulty. Hence, drug development of NO mimetics must rely upon measurement of the NO donating specie (i.e., a prodrug) and a downstream marker of efficacy without directly measuring the molecule, NO, that is responsible for biological effect. The focus of this review is to catalog in vivo attempts to monitor the pharmacokinetics (PK) of the NO donating specie and the pharmacodynamic (PD) readout of NO bioactivity.

Identification in silico and experimental validation of novel phosphodiesterase 7 inhibitors with efficacy in experimental autoimmune encephalomyelitis mice

A neural network model has been developed to predict the inhibitory capacity of any chemical structure to be a phosphodiesterase 7 (PDE7) inhibitor, a new promising kind of drugs for the treatment of neurological disorders. The numerical definition of the structures was achieved using CODES program. Through the validation of this neural network model, a novel family of 5-imino-1,2,4-thiadiazoles (ITDZs) has been identified as inhibitors of PDE7. Experimental extensive biological studies have demonstrated the ability of ITDZs to inhibit PDE7 and to increase intracellular levels of cAMP. Among them, the derivative 15 showed a high in vitro potency with desirable pharmacokinetic profile (safe genotoxicity and blood brain barrier penetration). Administration of ITDZ 15 in an experimental autoimmune encephalomyelitis (EAE) mouse model results in a significant attenuation of clinical symptoms, showing the potential of ITDZs, especially compound 15, for the effective treatment of multiple sclerosis.

Design, synthesis, and pharmacological evaluation of novel hybrid compounds to treat sickle cell disease symptoms. part II: furoxan derivatives

Phthalimide derivatives containing furoxanyl subunits as nitric oxide (NO)-donors (3a-g) were designed, synthesized, and evaluated in vitro and in vivo for their potential uses in the oral treatment of sickle cell disease symptoms. All compounds (3a-g) demonstrated NO-donor properties at different levels. Moreover, compounds 3b and 3c demonstrated analgesic activity. Compound 3b was determined to be a promising drug candidate for the aforementioned uses, and it was further evaluated in K562 culture cells to determine its ability to increase levels of γ-globin expression. After 96 h at 5 μM, compound 3b was able to induce γ-globin expression by nearly three times. Mutagenic studies using micronucleus tests in peripheral blood cells of mice demonstrated that compound 3b reduces the mutagenic profile as compared with hydroxyurea. Compound 3b has emerged as a new leading drug candidate with multiple beneficial effects for the treatment of sickle cell disease symptoms and provides an alternative to hydroxyurea treatment.