RESUMO
Obesity and its associated disorders constitute a growing epidemic across the world. Numerous studies have demonstrated the presence of systemic oxidative stress in patients with obesity. In this study, we show the effects of oxidative stress present in the blood from obese patients on recombinant human insulin. Insulin was incubated with whole blood (WB) from overweight subjects (OW), obese 1 patients (O1), or normal weight volunteers (NW) (n=16 for each group). Whole blood from OW and O1, unlike WB from NW, increased the carbonyl content of insulin; however, only whole blood from O1 patients increased the amount of formazan present in the hormone. Interestingly, the incubation of insulin with WB from O1 provoked a decrease in the hypoglycemic activity of the hormone (18%), an effect due to insulin polymerization. In addition, we showed that the formation of the insulin polymer generated the formation of new epitopes and the development of a new immunogenicity. These observations show that oxidative stress present in the WB of O1 patients can result in abolition of the biological activity of insulin and contribute to the development of an immune response to the hormone.
Assuntos
Hipoglicemiantes/química , Resistência à Insulina , Insulina Regular Humana/química , Obesidade/sangue , Estresse Oxidativo , Adulto , Animais , Reações Antígeno-Anticorpo , Biomarcadores/sangue , Índice de Massa Corporal , Feminino , Formazans/análise , Humanos , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/farmacologia , Insulina Regular Humana/isolamento & purificação , Insulina Regular Humana/farmacologia , Camundongos , Obesidade/imunologia , Sobrepeso/sangue , Sobrepeso/imunologia , Oxirredução , Polimerização , Carbonilação Proteica , Proteínas Recombinantes/química , Adulto JovemRESUMO
BACKGROUND: Mexico has a high rate of cervical cancer which represents an important public health issue. The treatment for this disease depends on the extension of the tumor; for the initial stages surgery is recommended, and for locally advanced tumors, a combination of chemotherapy and radiotherapy is used. All this process affects natural antioxidant consumption and Quality of Life (QoL). OBJECTIVE: To find out the effect that supplementation with antioxidants (ß-carotene, vitamin C y vitamin E) has on oxidative stress, and quality of life in patient diagnosed with cervical cancer during treatments with cisplatin and radiotherapy. MATERIALS AND METHODS: We conducted a randomized, blind clinical trial in women with cervical cancer whose antineoplasic treatment was radiotherapy in and radiotherapy with cisplatin. Patients were randomly assigned to receive antioxidant therapy or a placebo. Plasma concentrations of malondialdehyde (MDA), free carbonyls, dityrosines, and carbonyl/protein rate in two different moments, before oncologic therapy, and after finishing oncology treatment, we also evaluated food consumption by using a validated food frequency questionnaire and a QOL questionnaire before treatment and after it was over. The effect of the antioxidant treatment was assessed by the use t-student test for independent and paired samples, as well as frequencies and X² for categorical variables. RESULTS: We evaluated 103 patients who were randomly assigned to receive treatment with antioxidants 49 (47.60%) and placebo 54 (52.40%). We did not find statistically significant differences in food or antioxidant consumption according to the food frequency questionnaires. Most of the patients consumed more energy than needed to meet their requirement, but they did not consume enough of most of the antioxidants according to the Recommended Dailiy Allowance (RDA) recommendation. Serum levels of plasma free carbonyls and carbonil/mg of protein ratio were statistically significant (p < 0.009) which shows protein protection regarding oxidative stress in the supplemented group, this information was similar to the one found in the QOL questionnaire, which showed that Global QOL was better in the supplemented group (p < 0.025). Most of the patients had lower α-tocopherol and retinol plasma levels than the recommended values. CONCLUSIONS: Antioxidant supplementation showed to be effective in reducing oxidative stress in proteins, but it did not on food ingestion, patients did not meet their antioxidants requirement in their diets, in spite of an excess in energy consumption. Antioxidant plasma levels in most of the patients were lower than normal. QoL score was better in the supplemented group.
Assuntos
Antioxidantes/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Qualidade de Vida , Neoplasias do Colo do Útero/psicologia , Adulto , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Antioxidantes/metabolismo , Terapia Combinada , Dieta , Suplementos Nutricionais , Método Duplo-Cego , Ingestão de Alimentos , Feminino , Humanos , México , Pessoa de Meia-Idade , Política Nutricional , Radioterapia/efeitos adversos , Neoplasias do Colo do Útero/terapiaRESUMO
BACKGROUND: Atherosclerotic ischaemic heart disease is the second leading cause of general mortality in Mexico due to the growing prevalence of atherosclerotic risk factors in our society. The data of the FRIMEX study (Factores de Riesgo en México, Risk Factors in Mexico), considered together with those of other contemporary epidemiological surveys, will aid in our comprehension of the current state of cardiovascular epidemics in Mexico. METHODS: Frequencies of obesity, hypertension and smoking, and total cholesterol and glucose in capillary blood were estimated in a non-probabilistic sample comprised of 140017 individuals (aged 44+/-13 years; 42% men and 58% women), from six Mexican cities (Mexico City, Guadalajara, Monterrey, Puebla, Leon and Tijuana). RESULTS: Obesity or overweight status was found in 71.9% of participants. Hypertension was found in 26.5%, and the proportions of awareness, treatment and control for this disease were 49.3, 73 and 36%, respectively. Prevalence of hypertension increased with age; while it was higher in men under 60 years of age, in the more aged individuals it was higher in women. Hypercholesterolaemia was found in 40% of the individuals and cholesterolaemia > or =240 mg/dl was significantly higher in women. Thirty-five and a half percent of men and 18.1% of women were smokers. Type 2 diabetes mellitus was found in 10.4% of participants. There was significant Pearson's correlation between body mass index and blood pressure, between hypertension and glucose levels, and between hypertension and total cholesterol concentrations. CONCLUSIONS: We conclude that this population has a high cardiovascular risk profile and a high probability of the occurrence of metabolic syndrome.