Efeito do dolutegravir sobre a disfunção endotelial induzida pela LDL oxidada

Abstract

Cardiovascular diseases (CVD) are a serious public health problem and are identified as the main cause of death worldwide. Therefore, they are a matter of concern for the general population, the scientific community and especially for people with the human immunodeficiency virus (HIV). Many CVDs are directly or indirectly related to the progression of atherosclerotic disease, which in turn is preceded by endothelial dysfunction. Over the years, knowledge about HIV infection has increased and, consequently, more efficient antiretrovirals (ART) have emerged, which have contributed to increasing the life expectancy of individuals living with the virus. These, in turn, began to live with diseases related to aging, the presence of HIV in the body and the adverse effects of ART, such as diabetes and dyslipidemia, which are risk factors for the occurrence of CVD. Recent work demonstrates that, regardless of viral infection, some ART therapies are associated with severe dyslipidemia with cardiovascular impact. Currently, 2nd generation integrase inhibitors, especially Dolutegravir (DTG - research object of this work), have been widely used in ART therapy, as they have good results in viral infection control and promise of few effects. adverse. However, its use time is relatively short and there are no detailed studies of its effects on the endothelium and vascular function. Given the above, this work verifies the effect of DTG on endothelial homeostasis and on endothelial dysfunction induced by oxidized LDL. Therefore, thoracic aorta rings from mice and human endothelial cells were exposed and incubated for 24 hours with LDLox, DTG or both stimuli simultaneously. Vascular reactivity, flow cytometry, ELISA and immunofluorescence studies were performed. The results found showed that LDLox was effective in promoting vascular dysfunction, as it reduced the contractile response induced by phenylephrine via increased NO bioavailability. In endothelial cell culture, it reduced eNOS and nNOS expression, increased iNOS expression, production of pro- inflammatory mediators (CCl-2, TNF and IL-6) and increased oxidative stress by increasing superoxide radicals. When associated with LDLox, DTG did not change the pattern of contraction induced by LDLox in aortic preparations. In endothelial cells, it prevented the increase of NO in the basal state or stimulated with ACh but did not alter the levels of superoxide radicals. Furthermore, among the constitutive NOS, only the concentration of 10 μM prevented the reduction of eNOS expression. However, DTG was able to reduce the increase in iNOS induced by LDLox, despite not reducing the levels of CCL-2, TNF and IL-6. Alone, DTG potentiated the vascular contraction induced by phenylephrine, associated with a lower bioavailability of NO. In endothelial cells, DTG did not alter basal or stimulated production of NO and superoxide radicals, did not alter eNOS and iNOS expression but reduced nNOS expression. Alone, DTG also did not alter the production of CCL-2, TNF and IL-6. Therefore, it can be concluded that DTG can worsen LDLox-induced vascular dysfunction despite reducing iNOS levels. Furthermore, regardless of exposure to LDLox, DTG was able to induce vascular dysfunction associated with a down-regulation of the NO pathway.