RESUMO
OBJECTIVES: ABCB1 gene polymorphisms can modify P-glycoprotein function with clinical consequences. METHODS: The 3435C>T polymorphism prevalence was analyzed using oligonucleotide probes and next-generation sequencing in 421 unrelated healthy individuals living in Cuba. Data were stratified by gender, ethnic background and residence. The genotype and allelic frequencies were determined. RESULTS: The genotype distribution met the Hardy-Weinberg equilibrium assumption. The allelic frequency was 63.5% for the 3435C variant. The genotype frequencies were 41.1% for CC, 44.9% for CT and 14.0% for TT. The allele and genotype distributions differed between individuals living in La Habana and Santiago de Cuba (p<0.05) when ethnic background was analyzed. The allelic distribution was similar among Admixed and Black subjects, and they differed from Caucasians. The CC genotype was equally distributed among Admixed and Black subjects, and they differed from Caucasians. The TT genotype frequency differed between Caucasians and Admixed. The CT genotype was distributed differently among the three groups. Similar distribution was obtained in Brazilians, whereas some similarities were observed in African, Spanish and Chinese populations, consistent with the mixed Cuban ethnic origin. CONCLUSIONS: This is the first report on allele and genotype frequencies of the 3435C>T polymorphism in Cuba, which may support personalized medicine programs.
Assuntos
Polimorfismo de Nucleotídeo Único , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Frequência do Gene/genética , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único/genética , PrevalênciaRESUMO
BACKGROUND: The aqueous extract of the Allophylus cominia (L) Sw (Sapindaceae) leaves has shown anti-diabetic, anti-obesity and anti-inflammatory properties. In the Caribbean region, it is typically used for the treatment of type-2 diabetes. METHODS: Considering the herb-drug interaction, the aim of this study was to evaluate the potential effects of the A. cominia extract on the cytochrome P450 (CYP) (rat hepatocyte model) and P-glycoprotein (P-gp) (4T1 cell line) systems. RESULTS: The extract did not decrease the cell viability after being assayed by the MTT test at up to 1500 µg/mL for 72 h. The exposure of the cultured rat hepatocytes to the product (up to 250 µg/mL) for 48 h increased the activities of CYP-1A2, 2C9, and 2E1 by 1.46-, 1.60-, and 1.51-fold, respectively, compared with the controls. The activities of CYP-2B6, 2D6, and 3A4 were not significantly altered, whereas the activity of P-gp decreased by 2- and 4-fold. In addition, the extracts at 100 and 200 µg/mL significantly increased doxorubicin cytotoxicity in these cells 24 h after treatment. CONCLUSIONS: The findings indicate that the A. cominia extract modulates the CYP and P-gp systems increasing sensitivity to doxorubicin. Further studies are necessary to evaluate the potential herb-drug interaction or chemosensitive properties.
Assuntos
Sistema Enzimático do Citocromo P-450/efeitos dos fármacos , Sistema Enzimático do Citocromo P-450/metabolismo , Interações Ervas-Drogas , Extratos Vegetais/farmacologia , Sapindaceae/química , Subfamília B de Transportador de Cassetes de Ligação de ATP/efeitos dos fármacos , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Doxorrubicina/farmacologia , Feminino , Masculino , Camundongos , Extratos Vegetais/química , Folhas de Planta/química , RatosRESUMO
The chemical composition and biological properties of Ulva fasciata aqueous-ethanolic extract were examined. Five components were identified in one fraction prepared from the extract by gas chromatography-mass spectrometry, and palmitic acid and its ethyl ester accounted for 76% of the total identified components. Furthermore, we assessed the extract's antioxidant properties by using the DPPH, ABTS, and lipid peroxidation assays and found that the extract had a moderate scavenging effect. In an experiment involving preexposition and coexposition of the extract (1-500 µg/mL) and benzo[a]pyrene (BP), the extract was found to be nontoxic to C9 cells in culture and to inhibit the cytotoxicity induced by BP. As BP is biotransformed by CYP1A and CYP2B subfamilies, we explored the possible interaction of the extract with these enzymes. The extract (25-50 µg/mL) inhibited CYP1A1 activity in rat liver microsomes. Analysis of the inhibition kinetics revealed a mixed-type inhibitory effect on CYP1A1 supersome. The effects of the extract on BP-induced DNA damage and hepatic CYP activity in mice were also investigated. Micronuclei induction by BP and liver CYP1A1/2 activities significantly decreased in animals treated with the extract. The results suggest that Ulva fasciata aqueous-ethanolic extract inhibits BP bioactivation and it may be a potential chemopreventive agent.
RESUMO
One of the difficulties in the comparison of results between laboratories working with the comet assay is the great diversity of parameters used to express DNA damage and the lack of conversion factors between the majority of them. Here we report a scorer-independent conversion curve to transform the values of DNA damage reported in arbitrary units (AU) into estimated percentage of DNA in the tail (E%T), and the results obtained in an intercomparison exercise where the effectiveness of this curve and two others proposed in the literature (E%T=AU/4 and E%T=(AU/5)+10) were tested. To obtain the conversion curve, human lymphocytes were first treated with radiation or H(2)O(2). Percentage of DNA in tail (%T) was then measured in 2100 comets (300 comets per treatment) using Casp image analysis software. Subsequently, using these values of %T, categories of 0, 1, 2, 3, and 4 were assigned to comets with %T [0-1), [1-25), [25-45), [45-70), and >70, and DNA damage was calculated in AU, as usual. DNA damage was induced in the interval 24-315AU (1.54-65.23%T). The best-fit conversion curve obtained by regression analysis was E%T=(AU-25.87)/4.46. In the intercomparison exercise, ten scorers from nine laboratories analyzed the same comet images (recorded on a compact disc) visually. The values reported in comet categories were transformed into AU and subsequently into E%T, using the three approaches mentioned above. The best agreement between E%T and %T measured by the software (S%T) was obtained with the conversion curve reported here, where the slope of E%T versus S%T from the ten scorers was not different from 1. Using this conversion curve, the overall mean difference between E%T and S%T was 1.4±2.62 and 57 (81%) of E%T values differ from S%T by less than 5 units. These findings show the strength of the scorer-independent conversion curve as a tool to compare results reported in AU or %T by different laboratories.