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2.
Hum Exp Toxicol ; 38(1): 82-94, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29896975

RESUMEN

OBJECTIVE:: Nitrogen oxide (NOx) pollution and human immunodeficiency virus (HIV)/AIDS intensify inflammation during pregnancy and linked with adverse birth outcomes (ABOs). MicroRNA (miRNA)-146a plays a crucial role in regulating inflammation in the NF-κB pathway. The G/C rs2910164 dampens miRNA-146a activity and linked with inflammatory diseases. The present study investigated whether HIV/AIDS and NOx exposure throughout pregnancy further intensifies ABO in Black South African women genotyped for the rs2910164. METHODS:: Pregnant women ( n = 300) were subdivided into low, medium and high NOx exposure groups, genotyped for the miRNA-146a G/C rs2910164 using polymerase chain reaction-restriction fragment length polymorphism, and further stratified based on HIV status. RESULTS:: Unstratified data (HIV+ and HIV- mothers combined): Mothers from the high NOx group with the variant C-allele had low blood iron levels ( p = 0.0238), and had babies with reduced birthweights ( p = 0.0283). As NOx increased, the prevalence of preterm birth and low birth weight also increased in mothers with the variant C-allele versus wildtype G-allele. HIV-infected mothers: In all NOx exposure groups, mothers with the variant C-allele had higher systolic blood pressure (low: p = 0.0386, medium: p = 0.0367 and high: p = 0.0109) and had babies with lower Appearance, Pulse, Grimace, Activity and Respiration scores at 1 min (low: p = 0.0190, medium: p = 0.0301 and high: p = 0.0361). CONCLUSION:: Maternal rs2910164 variant C-allele, NOx pollution and HIV/AIDS might collectively play a role in intensifying gestational hypertension and ABO.


Asunto(s)
Contaminantes Atmosféricos/análisis , Desarrollo Fetal , Infecciones por VIH/epidemiología , MicroARNs/genética , Óxidos de Nitrógeno/análisis , Nacimiento Prematuro/epidemiología , Adulto , Exposición a Riesgos Ambientales , Femenino , Genotipo , Infecciones por VIH/genética , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Polimorfismo de Nucleótido Simple , Embarazo , Sudáfrica , Adulto Joven
3.
Int J Immunogenet ; 45(2): 54-62, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29431293

RESUMEN

Interleukin (IL-)17A, plays a role in pathogenic defence, but is implicated in chronic inflammatory diseases, and has recently been associated with variable pregnancy outcomes. We investigated the role of maternal IL-17-[G197A]-specific effects of third-trimester IL-17 mRNA expression, NOx exposure levels and other variables on gestational age, in the Mother and Child in the Environment (MACE) birth cohort in South Africa. A total of 327 participants were genotyped for IL-17-[G197A] by polymerase chain reaction restriction-fragment length polymorphism (PCR-RFLP). Quantitative real-time PCR was used to quantitate IL-17-mRNA expression in whole blood. Multivariate linear regression analysis, stratified by IL-17-[G197A] genotype, was used to test for effects of NOx , IL17A/GAPDH, haemoglobin, body mass index, HIV-1 positivity, maternal education and income level on gestational age. Lower expression was associated with the IL-17-GG versus GA in the cohort and HIV-1-negative group (p = .0007, p = .0058), while no difference was observed in the HIV-1 positives. Elevated IL-17A expression was observed in the high NOx exposure groups, within IL-17[G197G] (p = .0004). IL-17[G197G] was associated with PTB (p < .0001), and the PTB group had lower IL-17A expression compared to the full-term group (p = .0002). IL-17 expression was associated with an increase in gestational age (p = .038), and NOx was associated with a decrease in gestational age in the IL-17[G197G] model (p = .046).


Asunto(s)
Exposición a Riesgos Ambientales/análisis , Interleucina-17/genética , Óxidos de Nitrógeno/análisis , Polimorfismo de Nucleótido Simple , Adolescente , Adulto , Estudios de Cohortes , Femenino , Expresión Génica , Predisposición Genética a la Enfermedad/genética , Genotipo , Edad Gestacional , Humanos , Recién Nacido , Modelos Lineales , Análisis Multivariante , Embarazo , Nacimiento Prematuro/genética , Sudáfrica , Adulto Joven
4.
Andrology ; 6(1): 166-175, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29179260

RESUMEN

Highly active antiretroviral therapy has evolved over the years, leading to a boost in the quality of life in people living with HIV and AIDS. However, growing evidence has shown that highly active antiretroviral therapy has deleterious effects on the testes and the overall reproductive capacity. Therefore, this study is to determine the adjuvant potential of Naringenin on highly active antiretroviral therapy-induced perturbations in fertility of male Sprague-Dawley rats. Thirty adult male Sprague-Dawley rats were divided into six groups viz - Control; H: 30 mg/kg of highly active antiretroviral therapy (EFV, 600 mg + FTC, 200 mg + TDF, 300 mg); N40: Naringenin, 40 mg/kg; N80: Naringenin, 80 mg/kg; HN40: highly active antiretroviral therapy + Naringenin, 40 mg/kg; HN80: highly active antiretroviral therapy + Naringenin, 80 mg/kg. The rats were euthanized after 4 weeks. Results showed that there was a significant decrease in sperm count (p < 0.001), spermatozoa with normal morphology (p < 0.001) and progressive sperm motility (p < 0.05) of H compared to the control and the HN groups. Likewise, fragmentations increased (p < 0.05) in tail lengths of sperm DNA in H compared to control. HN40 and HN80 decreased tail lengths compared to H (p < 0.001). There was also a decrease in %tail DNA and tail moment in HN40 (p < 0.001) compared to H. Luteinizing hormone significantly increased (p < 0.05) in HN40, HN80, and N40 (p < 0.001) but decreased in H (p < 0.05) compared to control. The diameter of the seminiferous tubules also decreased (p < 0.05) in H compared to control, N80, and HN40. Likewise, the area of the seminiferous tubules in group H decreased (p < 0.05) compared to N80 and HN80. The seminiferous tubules epithelium increased (p < 0.05) in N40 and HN40 compared to H. This study establishes that highly active antiretroviral therapy has deleterious effects on the testicular microanatomy, sperm parameters, and sperm DNA of Sprague-Dawley rats, which may impair fertility but Naringenin is a potential complimentary adjuvant.


Asunto(s)
Terapia Antirretroviral Altamente Activa/efectos adversos , Fragmentación del ADN/efectos de los fármacos , Antagonistas de Estrógenos/farmacología , Flavanonas/farmacología , Espermatozoides/efectos de los fármacos , Animales , Masculino , Ratas , Ratas Sprague-Dawley , Espermatozoides/patología
5.
Hum Exp Toxicol ; 37(7): 679-689, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28875725

RESUMEN

OBJECTIVE: Cytokines, molecules within the immune system that affect either a pro- or anti-inflammatory response, have previously been shown to influence birth outcomes. The maternal cytokine gene-environment interactions are thought to alter their expression, potentially influencing susceptibility to adverse birth outcomes. The aim of this study was to determine the association between the maternal interleukin-1ß (IL-1ß) haplotype and expression variation with oxides of nitrogen (NOx) levels, and thereafter investigate the IL-1ß haplotype-specific effects of NOx exposure levels, IL-1ß mRNA expression and other variables on gestational age. MATERIAL AND METHODS: Using the prospective Mother and Child in the Environment (MACE) birth cohort in Durban, South Africa, 335 participants were genotyped for the IL-1ß haplotype. Previous studies showed that three single nucleotide polymorphisms (SNPs), IL-1ß-1464G/C, -511C/T and -31C/T, constitute the IL-1ß functional haplotype. These SNPs were genotyped using a restriction fragment length polymorphism assay, while IL-1ß mRNA expression was measured using a quantitative real-time polymerase chain reaction assay. Individual estimates of NOx exposure were obtained by land use regression modelling. A multivariate linear regression analysis was employed to test for significant effects on gestational age. RESULTS: IL-1ß mRNA expression was found to possess a haplotype-dependent effect ( p = 0.0001) and its expression levels positively correlated with NOx levels ( r = 0.34; p = 0.006). In the high haplotype model, a unit increase in NOx exposure level was associated with a decrease in gestational age by 1 week ( p = 0.02). Furthermore, gestational age decreased by 0.9 weeks for every unit increase of IL-1ß mRNA expression level ( p = 0.025). HIV-1 positivity was associated with a 0.2-week decrease in gestational age ( p = 0.035) in the intermediate haplotype model and a 0.4-week decrease in the high haplotype model ( p = 0.044). CONCLUSION: These data have implications for better understanding the effect of prenatal NOx exposure on gestational age and demonstrate the role of the IL-1ß haplotype in modulating the effects of NOx exposure.


Asunto(s)
Contaminantes Atmosféricos/análisis , Exposición a Riesgos Ambientales/análisis , Edad Gestacional , Interleucina-1beta/genética , Óxidos de Nitrógeno/análisis , Adolescente , Adulto , Femenino , Genotipo , Haplotipos , Humanos , Polimorfismo de Nucleótido Simple , ARN Mensajero/metabolismo , Sudáfrica , Adulto Joven
6.
Hum Exp Toxicol ; 37(7): 762-771, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29027485

RESUMEN

The geographical distribution of oesophageal cancer is linked to the exposure of fumonisin B1 (FB1), a mycotoxin produced by fungi that contaminates staple food worldwide. Non-genotoxic carcinogens like FB1 disturb homeostasis through increased cell proliferation or suppression of apoptosis. This study investigated the involvement of FB1 (0-20 µM) in spindle-shaped N-cadherin (+) CD45 (-) osteoblastic (SNO) cell death. Cell viability and death were assessed using the MTS and Annexin V-Fluos assays, respectively. Caspase activities were determined luminometrically and the comet assay assessed DNA damage. Induction of oxoguanine glycosylase 1 (OGG1) was measured using quantitative Polymerase Chain Reaction (qPCR), while cleaved poly (ADP-ribose) polymerase 1 (PARP-1) and Bax were determined by western blotting. Cell viability and PARP-1 cleavage were not affected by 1.25 µM FB1, but phosphatidylserine externalization, Bax protein expression, caspase activity, comet tail length and OGG1 transcripts were increased. The reduced cell viability in 10 µM FB1-treated cells was accompanied by corresponding increases in externalized phosphatidylserine, Bax, caspase-3/7 activity and cleaved PARP-1. The OGG1 transcripts were not significantly increased, but comet tails were increased. Bax, caspase-3/7 activities and cleaved PARP-1 were inhibited at 20 µM FB1. In addition, the OGG1 transcript levels were decreased ( p < 0.0001) along with comet lengths ( p < 0.0001). This study showed that FB1-induced apoptosis in SNO cells may be caspase-dependent or caspase-independent; the pathway used depends on the exposure concentration.


Asunto(s)
Apoptosis/efectos de los fármacos , Fumonisinas/toxicidad , Caspasas/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ensayo Cometa , Relación Dosis-Respuesta a Droga , Neoplasias Esofágicas , Humanos
7.
J Photochem Photobiol B ; 173: 626-639, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28709077

RESUMEN

The world has a rich diversity of indigenous medicinal plants. The World Health Organization (WHO) gives high priority to eco-friendly, non-hazardous and cost effective healthcare such as the use of medicinal plants to treat various illnesses, including Human immunodeficiency virus (HIV) infection and Acquired immune deficiency syndrome (AIDS), tuberculosis (TB), diabetes mellitus (DM), malaria, and cancer. In developing countries, a high proportion of the population tends to use complementary and alternative medicines (CAM) together with conventional prescription drugs. Globally, CAM has been used in both developed and developing countries. In China, 30-50% of medicinal use is based on traditional alternative medicine. In Africa, it is estimated that 80% of primary health care is CAM, whilst in the USA, about 158 million people us CAM. This increase is due to three main influences: improve their eminence of life, relieve symptoms and preclude long-term complications. Despite the advances and advantages of conventional pharmaceutical medication, these are associated with long-term side effects and pose risks of inefficacy for treatment of chronic diseases such as cancer and DM. The biosynthesis of metal nanoparticles (NPs) using medicinal plants has received considerable attention as a proper alternative to using hazardous chemical and physical synthetic techniques. Plants are being exploited for their unique metal tolerance and effective production of gold metal NPs. A single medicinal plant contains an orchestra of chemical elements (e.g. proteins, vitamins, enzymes, amino acids, polysaccharides and organic compounds) that are "environmentally benign, yet chemically complex" and therefore serve as ideal tools for enhanced medicinal applications. It is reported that phytocompounds such as terpenoids, polysaccharides, polyols and flavones take part in the bio-reduction, stabilization and bio-capping mechanisms to form stable gold and silver NPs. Also the inhibitory potential of plant compounds against diabetic targets followed by a study of enzyme inhibitor kinetics, ligand binding dynamics supported by in silico docking studies that reveal the mode of bioactive compounds and their inhibitory activities. The present review focuses on the potential anticancer, antidiabetic and antimicrobial activity of phyto-synthesized gold and silver NPs. In phytonanotherapy, synergistic features of plant and metal NPs are unique as they offer healing properties that may be the clinical bioequivalent to many synthetic drugs, with minimal side effects. This could provide alternative treatment for chronic diseases that is efficient to overcome the disadvantages of synthetic monotherapy and allows medicinal plant therapy to co-exist with current synthetic treatments. This creates a much needed paradigm shift for further clinical studies in non-communicable and communicable diseases.


Asunto(s)
Diabetes Mellitus/tratamiento farmacológico , Nanopartículas del Metal/química , Antibacterianos/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Diabetes Mellitus/patología , Oro/química , Tecnología Química Verde , Humanos , Hipoglucemiantes/química , Hipoglucemiantes/aislamiento & purificación , Hipoglucemiantes/uso terapéutico , Medicina Tradicional , Nanopartículas del Metal/uso terapéutico , Neoplasias/tratamiento farmacológico , Plantas Medicinales/química , Plantas Medicinales/metabolismo
8.
J Photochem Photobiol B ; 169: 75-82, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28288401

RESUMEN

The bio-synthesized DTAuNPs have an average size of 21nm. The aggregation extent depends on the concentration of melamine, which was validated by UV-vis spectra and visual method of melamine detection was developed. The major observation in this method was the color change of DTAuNPs from red to purple due to the aggregation of ligand capped gold nanoparticles instigated by melamine. The reaction of color changes were processed due to the shifting of bonding in hydrogen in between nanoparticles and melamine. The aggregation extent depends on the concentration of melamine, which can be validated UV-vis spectra and visual method of detecting melamine is developed. The electron density and conventional UV-vis, FTIR spectroscopy and DFT studies on the ligand was performed using computational methods. The theoretical and experimental data for the energy transitions and the molar extinction coefficients of the ligands studied has been obtained. Further, the ligand capped gold nanoparticles was assessed for cytotoxicity against A549 cells which resulted in significant decrease in cell viability was noted in 50µg/mL DTAu, 4-ATP and AXT treated cells at 2h (85% and 66%) and 6h (83% and 36%) respectively, (p<0.01) were studied and reported in this manuscript.


Asunto(s)
Nanopartículas del Metal/química , Triazinas/análisis , Células A549 , Aminas , Supervivencia Celular/efectos de los fármacos , Color , Oro/química , Humanos , Ligandos , Límite de Detección , Técnicas Psicológicas , Análisis Espectral , Compuestos de Sulfhidrilo
9.
Hum Exp Toxicol ; 36(3): 238-246, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27142357

RESUMEN

The objective of this study was to determine if the association between exposure to ambient air pollutants such as sulfur dioxide, nitrogen dioxde (NO2), nitrous oxide (NO), and PM10, and variation in lung function measures was modified by genotype. A validated questionnaire was administered to 71 African children to evaluate prevalence of respiratory symptoms. Atopy was evaluated by skin-prick testing and bihourly measures of lung function (spirometry) were collected. Gaseous air pollutant concentrations were monitored continuously. CD14 polymorphism was genotyped and plasma CD14 levels were measured. There was no statistically significant association between the CD14 (159) CT+TT polymorphism with any asthma-related phenotype. There was a significant association between lung function (forced expiratory volume in 1 second intraday variability) and NO2 and NO among participants carrying the CD14 CT/TT genotype for lags 1, 2, and the 5-day average. Similarly, statistically significant gene-pollutant interactions ( p < 0.05) were found with NO and CD14 CT/TT at lag 2 and for the 5-day average. While there was no association with any respiratory phenotype (as determined by symptoms), the CD14 CT/TT genotype appeared to be protective to increased exposure to NO2 and NO.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Receptores de Lipopolisacáridos/genética , Pulmón/efectos de los fármacos , Polimorfismo Genético , Niño , Femenino , Humanos , Pulmón/fisiopatología , Masculino , Pruebas de Función Respiratoria , Sudáfrica
10.
J Photochem Photobiol B ; 165: 87-95, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27776261

RESUMEN

The biosynthesis of nanostructured biopalladium nanoparticles (PdNPs) from an aqueous solution of crystalline palladium acetate is reported. For the synthesised PdNPs in solution, an agroforest biomass waste petal of Moringa oleifera derived bis-phthalate was used as natural reducing and biocapping agents. Continuous absorption in the UV region and subsequent brown colour change confirmed the formation of PdNPs. A strong surface plasmon peak for PdNPs occurred at 460nm. PdNPs were characterized by SEM with EDX, FTIR, TEM and DLS. The chemical composition of the aqueous extract was determined by GC-MS coupled with FTIR and 1NMR. The catalytic degradation effect by PdNPs on industrial organic toxic effluents p-nitrophenol (PNP) and methylene blue dye was monitored by UV Spectroscopy. On the other hand PdNPs catalysed the base mediated suzuki coupling reaction for biphenyl synthesis, in water. Moreover, PdNPs were found to be reusable catalysts. Toxicity studies of PdNPs showed that the death of brine shrimp to be <50%. Therefore, PdNPs displayed potential for further anticancer studies via tumour cell lines. The in vitro cytotoxicity evaluation of the extract capped nanoparticles was carried out using human lung carcinoma cells (A549) and peripheral lymphocytes normal cells by MTT cell viability assay. Also, PdNPs showed antibacterial activity against Enterococcus faecalis among the different tested strains, including Bacillus cereus, Staphylococcus aureus, Esherichia coli and Candida albicans, Candida utilis.


Asunto(s)
Flores/química , Nanopartículas del Metal , Moringa oleifera/química , Paladio/química , Extractos Vegetales/química , Catálisis , Línea Celular , Humanos , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Tamaño de la Partícula , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier
11.
Int. j. morphol ; 34(1): 102-109, Mar. 2016. ilus
Artículo en Inglés | LILACS | ID: lil-780482

RESUMEN

Testicular toxicity has been implicated in highly active anti-retroviral therapy (HAART) treatment. Hence there is need to identify an effective antioxidant product that can alleviate testicular necrosis due to HAART administration. Forty eight adult male Sprague-Dawley rats were used in this study. The animals were divided into eight (8) groups: A-H (n= 6). Group A animals received normal saline as the control; Group B was given Nevirapine (Nv); Group C was given Kolaviron (Kv); Group D was given vitamin C; Group E was given Nv and Kv; Group F was given Nv and Vitamin C; Group G was given Nv for 56 d and Kv for 28 d serving as a withdrawal group; Group H was given corn oil. Nv, Kv and Vit. C were given at 1.54, 200 and 250 (mg·kg)/bw respectively while all administrations were through oral gavage. The body weights were taken every other day. Thereafter, they were anaesthetized with halothane. The testes were excised, weighed, fixed in Bouin's fluid and stained with H&E while the epididymes removed for semen fluid analyses. The results showed a significant (P<0.05) decrease in sperm motility in group E (Nevirapine + kolaviron) when compared with group F (Nevirapine + Vitamin C) while Sperm count was not significantly different (P>0.05) across the groups. The testicular histoarchitectural studies revealed indistinct spermatogonia, necrotic interstititial endocrine cells in the altered interstitial space, fragmented spermatids, atrophy of mature spermatocytes, degenerated germ cells, obliterated seminiferous tubules lumen, undifferentiated spermatogonia and cellular debris in the somniferous tubules lumen of nevirapine administered group but normal across the other groups. In the testis, there were no significant reduction in SOD, Catalase and GPx activities but a significant decrease in GST activity (P<0.001) when group E was compared with group F. In conclusion, vitamin C presents a better remediation in nevirapine induced spermiotoxicity compared to kolaviron in Sprague-Dawley rats.


La toxicidad testicular ha sido implicada en la terapia antirretroviral altamente activa (TARAA). Por lo tanto existe la necesidad de identificar un producto antioxidante eficaz que pueda aliviar la necrosis testicular en la administración de la TARAA. Cuarenta y ocho ratas macho Sprague-Dawley adultas fueron utilizadas. Los animales se dividieron en ocho (8) grupos: AH (n= 6). Grupo A, animales recibieron solución salina normal como el control; Grupo B, recibió Nevirapina (Nv); Grupo C, recibió Kolaviron (Kv); Grupo D, recibió vitamina C; Grupo E, recibió Nv y Kv; Grupo F, recibió Nv y vitamina C; Grupo G, recibió Nv durante 56 d y Kv por 28 d como un grupo de retirada; Grupo H, recibió aceite de maíz. Nv, Kv y Vit. C se administraron en dosis de 1, 54, 200 y 250 (mg · kg) de peso corporal respectivamente; todas las administraciones fueron por sonda oral. Los pesos corporales se tomaron cada dos días. A partir de ese momento los animales fueron anestesiados con halotano. Los testículos fueron extirpados, pesados y fijados en solución de Bouin y teñidos con H&E, mientras que el epidídimo se retiró para analizar el semen. Los resultados mostraron un descenso (p<0,05) en la motilidad de los espermatozoides en el grupo E (Nevirapina + Kolaviron) en comparación con el grupo F (Nevirapina + vitamina C), mientras que el recuento espermático no mostró diferencias significativas (P>0,05) entre los grupos. El estudio de la histoarquitectura testicular reveló espermatogonias indiferenciadas, con células intersticiales necróticas en el espacio intersticial y espermátidas fragmentadas. Además, en el grupo que recibió Nevirapina mostró espermatocitos maduros atrofiados, degeneración de células germinales, lumen de los túbulos seminíferos obliterados, espermatogonias indiferenciadas y restos celulares en el lumen de los tubulos seminíferos. En el resto de los grupos los resultados fueron normales. En el testículo hubo una reducción significativa en las actividades de la superóxido dismutasa, catalasa y glutatión peroxidasa, pero una disminución significativa en la actividad glutatión S-transferasa (P <0,001) al comparar los grupo E y F.


Asunto(s)
Animales , Masculino , Ratas , Antioxidantes/farmacología , Garcinia kola/química , Nevirapina/toxicidad , Extractos Vegetales/farmacología , Superóxido Dismutasa/antagonistas & inhibidores , Testículo/efectos de los fármacos , Fármacos Anti-VIH/toxicidad , Ácido Ascórbico/farmacología , Biflavonoides/farmacología , Peso Corporal , Catalasa/antagonistas & inhibidores , Glutatión Peroxidasa/antagonistas & inhibidores , Ratas Sprague-Dawley , Semillas , Recuento de Espermatozoides , Motilidad Espermática/efectos de los fármacos , Testículo/enzimología , Testículo/patología
12.
Int Arch Occup Environ Health ; 89(5): 785-92, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26864539

RESUMEN

PURPOSE: To determine the effect of petrol exposure on DNA integrity in peripheral blood lymphocytes among petrol attendants and a non-exposed comparison population. METHODS: This cross-sectional study included 101 fuel station employees and 50 office-based non-exposed workers in Durban, South Africa. Participants were interviewed using a validated questionnaire. Genomic DNA was extracted from peripheral lymphocytes for the benzo(a)pyrene diol epoxide (BPDE)-DNA adduct assay (ELISA), and DNA damage was determined using the comet assay and reported as percentage tail DNA. RESULTS: The exposed (n = 101) and non-exposed participants (n = 50) varied with regard to age, housing, smoking, and proximity to industry and petrol stations. Among the exposed, the mean duration of employment in the fuel industry was 5.8 years (SD = 4.6), and among those pumping fuel (n = 75), the mean metric tons of petrol pumped in the past 12 months per worker was 199.2 (SD = 88.9). The mean percentage tail DNA varied significantly between exposed and non-exposed groups: 23.8 % (SD = 13.3) and 8.1 % (SD = 1.8) (p < 0.01), respectively. A significant difference existed between the groups for BPDE-DNA adducts: 30.0 ng/ml (SD = 12.7) and 18.1 ng/ml (SD = 18.2) (p < 0.0001), respectively. Regression models, adjusting for cigarette smoking, age, and sex, showed a 16.5 greater percentage tail DNA among the exposed compared to non-exposed (95 % CI 11.8-21.1 %), while the exposed group had a 12.9 ng/ml greater increase in BPDE-DNA adducts has compared to the unexposed (95 % CI 7.2-18.7 ng/ml). Cigarette smoking resulted in almost a 3.5 % increase in percentage tail DNA. CONCLUSION: Our study adds to the literature that long-term, low-dose exposure to vehicular fuels is likely to result in altered DNA integrity and genotoxicity among petrol attendants. These results strengthen the case that these workers must be afforded appropriate protection to prevent serious adverse outcomes.


Asunto(s)
Daño del ADN , ADN/efectos de los fármacos , Linfocitos/efectos de los fármacos , Exposición Profesional/efectos adversos , Contaminación por Petróleo/efectos adversos , Petróleo/toxicidad , 7,8-Dihidro-7,8-dihidroxibenzo(a)pireno 9,10-óxido , Adulto , Ensayo Cometa , Estudios Transversales , Aductos de ADN/efectos de los fármacos , Femenino , Humanos , Industrias , Masculino , Persona de Mediana Edad , Análisis de Regresión , Sudáfrica , Encuestas y Cuestionarios , Factores de Tiempo
13.
Toxicon ; 99: 1-5, 2015 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-25772858

RESUMEN

Patulin (PAT), a mycotoxin contaminant of apples and apple products, has been implicated in nephrotoxicity. PAT depletes glutathione (GSH) and elevates reactive oxygen species (ROS). The antioxidant (AO) response is activated by Nuclear erythroid 2-related factor (NRF2) and enhanced by Silent information regulator 3 (SIRT3). The effects of PAT on these molecules have yet to be examined. We investigated the effects of PAT on AO response survival pathways in human embryonic kidney cells (HEK293). PAT cytotoxicity on HEK293 cells was evaluated (MTT assay; 24 h; [0-100 µM]) to determine an IC50. GSH levels were measured using luminometry. Intracellular ROS was evaluated by flow cytometry. Protein expression of Keap1, NRF2, SIRT3 and PGC-1α was quantified by western blotting and gene expression of SOD2, CAT and GPx was evaluated by qPCR. PAT caused a dose dependent decrease in HEK293 cell viability and a significant increase in levels of intracellular ROS (p = 0.0006). A significant increase in protein expression (p = 0.029) was observed. PAT increased gene expression of SOD2 and CAT (p = 0.0043), however, gene expression of GPx was significantly reduced (p = 0.0043). These results show the up-regulation of NRF2 mediated AO mechanisms in response to PAT toxicity.


Asunto(s)
Regulación de la Expresión Génica/efectos de los fármacos , Riñón/efectos de los fármacos , Mutágenos/toxicidad , Factor 2 Relacionado con NF-E2/agonistas , Estrés Oxidativo/efectos de los fármacos , Patulina/toxicidad , Factores de Transcripción/agonistas , Supervivencia Celular/efectos de los fármacos , Glutatión/metabolismo , Células HEK293 , Humanos , Concentración 50 Inhibidora , Riñón/metabolismo , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Oxidación-Reducción , Oxidorreductasas/antagonistas & inhibidores , Oxidorreductasas/química , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Especies Reactivas de Oxígeno/agonistas , Especies Reactivas de Oxígeno/metabolismo , Sirtuina 3/genética , Sirtuina 3/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
14.
Hum Exp Toxicol ; 34(8): 838-47, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25403174

RESUMEN

Chronic air pollution exposure during pregnancy can cause oxidative stress leading to adverse birth outcomes. The aim of this study was to assess and compare oxidative stress response in peripheral lymphocytes isolated from pregnant women from a highly industrialized locale (south Durban (SD); n = 50) and a control with lower air pollutant levels (north Durban (ND); n = 50). Oxidative stress response was measured by quantifying malondialdehyde (MDA) levels and a SuperArray gene panel. Mitochondrial function (adenosine triphosphate (ATP) levels and mitochondrial depolarization), DNA integrity (comet assay and mitochondrial DNA (mtDNA) viability) and DNA repair (OGG1) were assessed. Antioxidant response was assessed by quantification of glutathione (GSH) and SOD2, nuclear factor erythroid 2-related factor 2 (Nrf2) and uncoupling protein 2 (UCP2) protein and messenger RNA (mRNA) expression. Levels of MDA (p = 0.9), mitochondrial depolarization (p = 0.88), ATP (1.89-fold), SOD2 (1.23-fold) and UCP2 (1.58-fold) gene expression were elevated in the SD group with significantly higher UCP2 protein levels (p = 0.05) and longer comet tail length (p = 0.0004). The expression of Nrf2 protein (p = 0.03) and mRNA levels (-1.37-fold), GSH concentration (p < 0.0001), mtDNA amplification (-2.04-fold) and OGG1 mRNA (-2.78-fold) activity were decreased in the SD group. Of the 84 oxidative stress-related genes evaluated, 26 were differentially regulated. Pregnant women exposed to higher air pollutant levels showed increased markers for oxidative stress and compromised DNA integrity and repair.


Asunto(s)
Contaminación del Aire , Exposición Materna , Estrés Oxidativo , Antioxidantes/metabolismo , Daño del ADN , Femenino , Humanos , Embarazo , Sudáfrica
15.
Andrology ; 2(5): 772-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24919589

RESUMEN

The increased accessibility of antiretroviral therapy continues to positively drive the reduction in viral load and survival of patients despite the attendant reproductive toxicities. We propose that testicular damage caused by highly active antiretroviral therapy (HAART) can be attenuated by antioxidant treatment by investigating the testicular histomorphologic and stereological effects of antiretroviral drugs and its interaction with antioxidants using an experimental animal model. Sprague-Dawley rats were divided into seven groups of six rats per group (A, B... G) using simple random sampling and treated orally with 0.9% normal saline as placebo, a HAART cocktail of stavudine, lamivudine and nevirapine using the adjusted human therapeutic doses of 200, 600 and 350-400 mg/day, respectively, and antioxidants ascorbic acid (vitamin C) and I.M α-tocopherol (vitamin E). Animals were killed after 4 weeks and testicular tissue harvested and processed for light microscopy and stereological evaluations. The results were interpreted by a Veterinary pathologist blinded to the study. No animal died during the experimental period. The histopathological assessment of the testis of animals treated with placebo, ascorbic acid alone and α-tocopherol alone as well as vitamin E + HAART displayed normal testicular microanatomy. Groups treated with HAART alone, HAART + vitamin C + vitamin E and vitamins C + HAART showed extensive seminiferous tubular atrophy, necrosis and hypocellularity in the histoarchitectural patterns. While testicular cross-sectional area of seminiferous tubules remained unaffected by HAART, epithelial heights significantly decreased (p < 0.05) when compared with controls. There was marked (p < 0.05) increased in testicular-body weight ratio in HAART group. The results show that vitamin E could be useful in protecting testicular tissue from toxicities of HAART regimes as these results mirrors stereological data for the groups. HAART presents with deleterious histopathological changes in the testes causing tubular atrophy with altered morphometric indices. Supplementation with vitamin E appears to be a better adjuvant antioxidant that ameliorates these deleterious effects.


Asunto(s)
Fármacos Anti-VIH/efectos adversos , Antioxidantes/uso terapéutico , Terapia Antirretroviral Altamente Activa/efectos adversos , Túbulos Seminíferos/patología , Animales , Fármacos Anti-VIH/farmacología , Ácido Ascórbico/uso terapéutico , Atrofia/patología , Atrofia/prevención & control , Lamivudine/farmacología , Masculino , Modelos Animales , Necrosis/patología , Necrosis/prevención & control , Nevirapina/farmacología , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Estavudina/farmacología , alfa-Tocoferol/uso terapéutico
16.
Colloids Surf B Biointerfaces ; 105: 87-91, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23352951

RESUMEN

Stable AgNPs were formed in vitro by reacting AgNO3 (aq) solution with the aqueous plant leaf extract. UV-vis revealed the surface plasmon resonance λmax at 448 nm and the absorbance steadily increased in intensity as a function of reaction time. Transmission electron microscope (TEM) and XRD studies were used to characterize the AgNPs; the size was 4-35 nm. Dynamic light scattering (DLS) was used as supporting evidence to determine hydrodynamic size and zeta potential recorded as 80.27 nm and -24.7 mV, respectively. FT-IR spectra suggest that AgNPs are capped with protein molecules and other water soluble phytocompounds such as saponins and glycosides which also behave as stabilizing agents; TEM images indicate a visible layer surrounding the AgNPs. Prominent absorption bands at 3380 and 1642 cm(-1) are assigned to alcohol and carbonyl groups, respectively. (1)H NMR of the neat aqueous plant extract indicates presence of a complex mixture of compounds; however the chemical shift at δ 6.0-8.0 and 1.0-4.0 ppm indicates the presence of few aromatic but abundant aliphatic compounds, respectively. Toxicity of AgNPs on lung cancer cells (A549) and normal healthy peripheral lymphocytes (PLs) at 10 µg/ml and 50 µg/ml was assessed using the MTT, ATP and lactate dehydrogenase assays. Viability data for A549 cells showed a 21% (10 µg/ml) and 73% (50 µg/ml) cell viability after 6h exposure to AgNPs compared to 117% (10 µg/ml) and 109% (50 µg/ml) cell viability of normal peripheral lymphocytes. Lactate dehydrogenase was only significantly altered at 50 µg/ml AgNPs treated cells from 2.43±0.04 units to 0.77±0.04 units.


Asunto(s)
Albizzia/química , Neoplasias Pulmonares/tratamiento farmacológico , Linfocitos/efectos de los fármacos , Nanopartículas del Metal/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Nitrato de Plata/química , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Humanos , L-Lactato Deshidrogenasa/metabolismo , Neoplasias Pulmonares/patología , Linfocitos/citología , Espectroscopía de Resonancia Magnética , Microscopía Electrónica de Transmisión , Espectroscopía Infrarroja por Transformada de Fourier , Resonancia por Plasmón de Superficie , Difracción de Rayos X
17.
Cardiovasc J Afr ; 23(10): 563-71, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23192261

RESUMEN

In humans and other multicellular organisms that have an extended lifespan, the leading causes of death are atherosclerotic cardiovascular disease and cancer. Experimental and clinical evidence indicates that these age-related disorders are linked through dysregulation of telomere homeostasis. Telomeres are DNA protein structures located at the terminal end of chromosomes and shorten with each cycle of cell replication, thereby reflecting the biological age of an organism. Critically shortened telomeres provoke cellular senescence and apoptosis, impairing the function and viability of a cell. The endothelial cells within atherosclerotic plaques have been shown to display features of cellular senescence. Studies have consistently demonstrated an association between shortened telomere length and coronary artery disease (CAD). Several of the CAD risk factors and particularly type 2 diabetes are linked to telomere shortening and cellular senescence. Our interest in telomere biology was prompted by the high incidence of premature CAD and diabetes in a subset of our population, and the hypothesis that these conditions are premature-ageing syndromes. The assessment of telomere length may serve as a better predictor of cardiovascular risk and mortality than currently available risk markers, and anti-senescence therapy targeting the telomere complex is emerging as a new strategy in the treatment of atherosclerosis. We review the evidence linking telomere biology to atherosclerosis and discuss methods to preserve telomere length.


Asunto(s)
Aterosclerosis/diagnóstico , Aterosclerosis/genética , Endotelio Vascular/patología , Homeostasis del Telómero , Telómero/fisiología , Animales , Apoptosis , Aterosclerosis/fisiopatología , Biomarcadores/metabolismo , Senescencia Celular , Endotelio Vascular/fisiopatología , Humanos , Pronóstico , Factores de Riesgo , Acortamiento del Telómero
18.
Methods Find Exp Clin Pharmacol ; 30(1): 25-35, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18389095

RESUMEN

Extracts of Persea americana Mill (Lauraceae) ("Avocado") have been traditionally used to treat hypertension and diabetes mellitus. Accordingly, we studied the hypoglycaemic and renal function effects of P. americana leaf ethanolic extracts (PAE) in STZ-induced diabetic rats. Oral glucose tolerance responses to various doses of PAE were monitored in fasted rats following a glucose load. Rats treated with deionized water or standard hypoglycaemic drugs acted as untreated and treated positive controls, respectively. Acute renal effects of PAE were investigated in anesthetized rats challenged with 0.077 M NaCl after a 3.5-h equilibration for 4 h comprising 1 h control, 1.5 h treatment and 1.5 h recovery periods. PAE was added to the infusate during the treatment period. Hepatic glycogen concentration was measured after 6 weeks of daily treatment with PAE. PAE induced dose-dependent hypoglycaemic responses in STZ-induced diabetic rats while subchronic PAE treatment additionally increased hepatic glycogen concentrations. Acute PAE infusion decreased urine flow and electrolyte excretion rates, whilst subchronic treatment reduced plasma creatinine and urea concentrations. These results indicate not only the basis of the ethnomedicinal use of P. americana leaf extract in diabetes management, but also of need for further studies to identify and evaluate the safety of PAE's bioactive compounds.


Asunto(s)
Glucemia/efectos de los fármacos , Diabetes Mellitus Experimental/tratamiento farmacológico , Persea , Fitoterapia/métodos , Insuficiencia Renal/prevención & control , Animales , Línea Celular , Relación Dosis-Respuesta a Droga , Gliburida/uso terapéutico , Hipoglucemiantes/uso terapéutico , Insulina/sangre , Pruebas de Función Renal , Túbulos Renales Distales/efectos de los fármacos , Túbulos Renales Proximales/efectos de los fármacos , Masculino , Metformina/uso terapéutico , Extractos Vegetales/uso terapéutico , Ratas , Ratas Wistar , Estreptozocina
19.
Phytomedicine ; 15(9): 699-709, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18406590

RESUMEN

Studies in our laboratories suggest that Sclerocarya birrea stem-bark ethanolic extract (SBE) has hypoglycemic properties. Accordingly, we investigated the effects of SBE on major complications of diabetes mellitus; blood glucose, renal function and mean arterial blood pressure (MAP) in non-diabetic and STZ-induced diabetic rats. Oral glucose tolerance test responses to various SBE doses (60, 120 and 240 mg kg(-1)) were studied in fasted rats following glucose load (0.86 g kg(-1), p.o.). Rats treated with deionized water (3 ml kg(-1) p.o.), or standard hypoglycemic drugs (insulin, 100 microg kg(-1), s.c.; metformin, 500 mg kg(-1), p.o. or glibenclamide, 500 microg kg(-1), p.o) acted as untreated and treated positive controls, respectively. Blood was collected in non-diabetic rats after 45 min of SBE, metformin or glibenclamide for plasma insulin determination. Acute SBE effects on renal function and MAP were studied in anesthetized rats challenged with hypotonic saline after 3.5h equilibration for 4h of 1h control, 1.5h treatment and 1.5h recovery periods. SBE was added to the infusate during the treatment period. Chronic effects were monitored for 5 weeks in animals daily treated with SBE (120 mg kg(-1) p.o.) while hepatic glycogen concentration was measured at the end of the experimental period. SBE exhibited dose-dependent reduction in blood glucose concentration. SBE and metformin did not affect plasma insulin secretion in non-diabetic rats, while glibenclamide increased plasma insulin concentration. The hypoglycemic effect of SBE treatment was associated with increased hepatic glycogen synthesis. Acute SBE administration did not significantly alter kidney function, but chronic SBE treatment for decreased plasma urea and creatinine concentrations of STZ-diabetic rats with concomitant increase in GFR by comparison with control rats at the corresponding period (0.7+/-0.2 vs. 1.4+/-0.3 ml min(-1)). SBE treatment reduced blood pressure in all groups of animals. The observations suggest that SBE has reno- and cardio-protective effects in diabetes mellitus. The current results indicate the basis for SBE use as complementary remedy in diabetes.


Asunto(s)
Anacardiaceae/química , Glucemia/análisis , Presión Sanguínea/efectos de los fármacos , Diabetes Mellitus Experimental/fisiopatología , Tasa de Filtración Glomerular/efectos de los fármacos , Extractos Vegetales/farmacología , Animales , Diabetes Mellitus Experimental/sangre , Etanol/química , Insulina/metabolismo , Secreción de Insulina , Masculino , Corteza de la Planta/química , Tallos de la Planta/química , Ratas , Ratas Wistar , Estreptozocina/administración & dosificación
20.
Ren Fail ; 29(4): 389-97, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17497459

RESUMEN

Previous observations indicate that Ficus thonningii (Blume) [Moraceae] stem-bark extracts may be useful in the control of diabetes mellitus. Accordingly, we investigated in some experimental animal paradigms the effects of F. thonningii stem-bark ethanolic extract (FTE) on renal and cardiovascular functions as complications of diabetes. Oral glucose tolerance tests were conducted in separate groups of non-diabetic and STZ-treated diabetic rats given glucose load (0.86 g x kg(-1), p.o.) after 18-h fast, followed by various FTE doses (60, 120, and 240 mg x kg(-1)). Rats treated with deionized water (3 mL x kg(-1) p.o.), or metformin (500 mg x kg(-1) p.o.) acted as untreated and treated positive controls, respectively. Blood glucose was monitored at 15-min intervals for the first hour, and hourly thereafter for 3 h. Acute effects of FTE on kidney function and mean arterial blood pressure (MAP) were investigated in anaesthetized rats challenged with hypotonic saline after a 3.5-h equilibration for 4 h of 1 h control, 1.5 h treatment, and 1.5 h recovery periods. FTE was added to the infusate during the treatment period. Chronic effects of FTE were studied in individually caged rats treated daily with FTE (120 mg x kg(-1), p.o.) for five weeks. Cytotoxicity of FTE was assessed by dye-reduction colorimetric (MTT) assay on MDBK and LLCPK1 kidney cell lines exposed for 24 h, 48 h, and 72 h to graded concentrations of the extract. Myocardial contractile performance was evaluated on rat isolated atrial muscle strips. FTE, like metformin, decreased blood glucose levels in non-diabetic and STZ-diabetic rats. Both acute and chronic FTE treatments did not affect renal function. In vitro studies demonstrated that FTE increased MDBK cell metabolic activity by an average of 15% (72 h), and LLCPK1 mirrored the controls. Acute intravenous infusion of FTE reduced the MAP from 119 +/- 1 mmHg to 98 +/- 4 mmHg. The MAP also was reduced throughout the five-week experimental study period. FTE also produced concentration-dependent, negative inotropic and chronotropic effects on rat isolated, electrically driven left-, and spontaneously beating right-, atrial muscle preparations. Our experimental findings suggest that FTE possesses reno- and cardio-protective effects in diabetes mellitus.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Diabetes Mellitus Experimental/tratamiento farmacológico , Ficus , Contracción Miocárdica/efectos de los fármacos , Fitoterapia , Animales , Células Cultivadas , Creatinina/sangre , Técnicas In Vitro , Riñón/efectos de los fármacos , Túbulos Renales Distales , Túbulos Renales Proximales , Masculino , Corteza de la Planta , Extractos Vegetales , Tallos de la Planta , Ratas , Ratas Wistar
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