ABSTRACT Ongoing insulin therapy maintains LDL receptors at highly expressed state in Type-1 diabetic people; yet Type-1 diabetics are liable of having higher plasma LDL level. This disparity has raised doubt on the probability of existence of functionally active LDL receptor in such people. Confocal microscopy and immunoprecipitation have made it evident that a portion of insulin and LDL receptors remain together in a co-localized mode, which only gets freed in presence of insulin. The findings of this study have shown that insulin therapy protects Type-1 diabetic people from the pathogenesis of atherosclerosis by decimating the inactivity of the co-localized LDL receptors in addition to its regular effect of having increased glucose tolerance. The existence of co-localized state of these two receptors and their dependence on insulin for independent activity has, at least, presented a reason for developing hypercholesterolemia and advanced coronary atherosclerotic lesion in chronic Type-1 diabetic subjects.
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