Pathophysiological role of leptin in patients with chronic renal failure, in kidney transplant patients, in patients with essential hypertension, andin pregnant women with preeclampsia

This paper is a summary of results obtained in our studies on leptinemia in patients with chronic renal failure treated with recombinant human erythro poietin (rHuEPO), in kidney transplant patients, in patients with essential hypertension, and in pregnant women with preeclampsia. Tn this study, we f ound that rHuEPO treatment has a suppressive effect on leptinemia in patien ts with endstage renal failure. These results suggest that the appetite sti mulating effect of rHuEPO may be mediated by a reduction of leptin synthesi s and release; At the early stage of successful kidney transplantation, a s ignificant decline of leptinemia was noticed, which was not related either to the excretory function of the graft or the kind and dose of immunosuppre ssants. In kidney transplant patients with grafts functioning well for 2.5 years, significantly elevated leptinemia was found. From these results, we may conclude that factors other than the excretory function of the graft an d the kind and dosage of immunosuppressants may be involved in the pathogen esis of abnormal leptinemia in these patients. Both in normotensive subject s and patients with essential hypertension, a positive correlation was foun d between leptinemia and mean blood pressure, suggesting that leptin may be involved in the regulation of blood pressure. Both healthy and preeclampti c pregnant women show higher leptinemia than nonpregnant women. In preeclam ptic women, leptin levels in maternal vein blood, umbilical cord blood, and amniotic fluid were significantly higher than respective values found in h ealthy pregnant women. In contrast to healthy pregnant and nonpregnant wome n, in women with preeclampsia, no correlation was found between the body ma ss index (BMT) and leptinemia. In preeclamptic women the abnormally elevate d leptinemia was not related to blood pressure. Finally, no correlation was found between leptinemia in maternal and umbilical cord blood. From these studies, it follows that the elucidation of abnormal leptin secretion in th e pathogenesis of preeclampsia needs further study.