Repercussões metabólicas e uso dos medicamentos sensibilizadores da insulina em mulheres com síndrome dos ovários policísticos / Metabolic repercussions and use of insulin-sensitizing drugs in women with polycystic ovary syndrome

A síndrome dos ovários policísticos (SOP) é um distúrbio endócrino-metabólico muito frequente no período reprodutivo. Quando associado ao distúrbio metabólico, as mulheres com SOP podem ter ainda risco acrescido para doença cardiovascular. O objetivo deste manuscrito é descrever as repercussões metabólicas, incluindo quais as principais, como investigar e as consequências desse distúrbio sobre a saúde da mulher. É uma revisão narrativa mostrando a implicação da resistência insulínica, das dislipidemias e da síndrome metabólica sobre o sistema reprodutor e sobre o risco cardiovascular da mulher com SOP, bem como do uso de sensibilizadores de insulina no seu tratamento. Conclui-se que a correção dos distúrbios metabólicos na SOP é benéfica tanto para o sistema reprodutor quanto para o cardiovascular. A primeira linha de tratamento é a mudança de estilo de vida e a perda de peso. Na resposta inadequada, o tratamento medicamentoso está recomendado. Nas mulheres com obesidade mórbida que não tiveram bons resultados com o tratamento clínico, a cirurgia bariátrica é uma opção.(AU)

Pretreatment with D-myo-inositol trisphosphate reduces infarct size in rabbit hearts: role of inositol trisphosphate receptors and gap junctions in triggering protection.

Pretreatment with D-myo-inositol-1,4,5-trisphosphate hexasodium (D-myo-IP(3)), the sodium salt of the second messenger inositol 1,4,5-trisphosphate (IP(3)), is cardioprotective and triggers a reduction of infarct size comparable in magnitude to that obtained with ischemic preconditioning. However, this observation is enigmatic; whereas IP(3) signaling is conventionally initiated by receptor binding, IP(3) receptors are typically considered to be intracellular, and D-myo-IP(3) is membrane-impermeable. We propose that this paradox is explained by the presence of poorly characterized external IP(3) receptors and hypothesize that: 1) infarct size reduction with D-myo-IP(3) is receptor-mediated; and 2) communication via gap junctions and/or hemichannels is required to initiate this protection. To investigate the role of receptor binding, isolated buffer-perfused rabbit hearts underwent 30 min of coronary occlusion (CO) and 2 h of reflow. Prior to CO, hearts received no treatment (controls), D-myo-IP(3), L-myo-IP(3) (enantiomer not recognized by the IP(3) receptor), D-myo-IP(3) + the IP(3) receptor inhibitor xestospongin C (XeC), or XeC alone. Infarct size, assessed by tetrazolium staining, was reduced with D-myo-IP(3) treatment, whereas hearts that received L-myo-IP(3) or D-myo-IP(3) + XeC showed no protection. To evaluate the contribution of gap junctions/hemichannels, additional control and D-myo-IP(3)-treated cohorts received a 5-min infusion of heptanol or Gap 27, two structurally distinct gap junction inhibitors, administered at doses confirmed to attenuate intercellular transmission of a gap junction-permeable fluorescent dye. There was no infarct-sparing effect of D-myo-IP(3) in inhibitor-treated hearts. These data support the concepts that infarct size reduction with D-myo-IP(3) is triggered by receptor binding and that communication via gap junctions/hemichannels is involved in initiating this protection.