Excessive production of very lowdensity lipoproteins vldls the primary lipid abnormality in the insulinresistant state

The primary metabolic abnormality associated with insulin-resistant states is overproduction of VLDLs. Because newly secreted VLDL particles are TG rich, the result is mild-to-moderate hypertriglyceridemia. If the overproduction of VLDLs is accompanied by other defects, such as Apo C-II deficiency (which reduces lipoprotein lipase activation), or a defect in the hepatic clearance of TG-rich Apo B-containing lipopro-teins, the result can be more severe hypertriglyceridemia (Fredrickson Types IV and V) and/or mixed dyslipidemia, involving elevations in TG and LDL-C (Types IIB and III).

Two features of the insulin-resistant state are centrally involved in the pathogenesis of VLDL overproduction: elevated circulating levels of FFAs and hyperinsulinemia. It appears that both must be present to generate overproduction of VLDLs. For example, in subjects with normal insulin sensitivity, a glucose infusion will not only increase the plasma insulin concentration but also lower levels of FFAs and reduce hepatic VLDL secretion (1). In contrast, patients with poorly controlled type 1 diabetes have low insulin levels and high concentrations of FFA but do not have elevated VLDL secretion (1). However, among insulin-resistant subjects with abdominal obesity, fasting and postprandial levels of circulating insulin are elevated, but this hyperinsulinemia does not normally suppress FFA release into the circulation; thus, both insulin and FFA levels are elevated, resulting in VLDL overproduction.

Increased hepatic exposure to FFAs inhibits Apo B degradation and leads to increased VLDL synthesis (9). Insulin promotes lipogenesis, which contributes to the TG pool available for incorporation into VLDL particles. In addition, insulin's ability to enhance Apo B degradation may be impaired in the insulin-resistant patient (9).

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Supplements For Diabetics

All you need is a proper diet of fresh fruits and vegetables and get plenty of exercise and you'll be fine. Ever heard those words from your doctor? If that's all heshe recommends then you're missing out an important ingredient for health that he's not telling you. Fact is that you can adhere to the strictest diet, watch everything you eat and get the exercise of amarathon runner and still come down with diabetic complications. Diet, exercise and standard drug treatments simply aren't enough to help keep your diabetes under control.

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