Hypersensitivity olipid mobilizing agents in essential fatty acid (EFA) deficient rats

Monounsaturatedn-9 fatty acids and adipocyte lipolysis in rats

To investigate the role of the monounsaturatedn-9 fatty acids (MUFA) in the lipolytic activity of adipocytes, a study was carried out in which an increase in MUFA was produced in the tissues by two different methods; by the dietary enrichment of oleic acid or by producing an essential fatty acid deficiency syndrome. For this, forty-five male Sprague–Dawley rats were fed with a normal-energy diet and were subdivided into three groups. The diets varied in the type of dietary fat; palmitic acid, olive oil, or soyabean oil+palmitic acid. At the end of the study measurements were taken of weight, plasma leptin, tissue concentration of fatty acids, fat-cell size in the epididymal and the omental adipose tissues, adipocyte lipolytic activity of both tissues after stimulation with adrenaline, and the capacity of insulin to inhibit lipolysis. The baseline and adrenaline-stimulated lipolytic activity were greater and the anti-lipolytic capacity of insulin lower in the animals undergoing an increase in MUFA in the tissues (palmitic-acid and olive-oil diets). The area under the curve of glycerol, used as an indicator of lipolytic activity, was positively correlated with the concentration of MUFA and negatively with polyunsaturated fatty acids in the adipose tissues. It is concluded that an increase in tissue MUFA, however obtained, induces an increase in lipolytic activity.

An expanded concept of "insurance" supplementation--broad-spectrum protection from cardiovascular disease

The preventive merits of "nutritional insurance" supplementation can be considerably broadened if meaningful doses of nutrients such as mitochondrial "metavitamins" (coenzyme Q, lipoic acid, carnitine), lipotropes, and key essential fatty acids, are included in insurance supplements. From the standpoint of cardiovascular protection, these nutrients, as well as magnesium, selenium, and GTF-chromium, appear to have particular value. Sophisticated insurance supplementation would likely have a favorable impact on many parameters which govern cardiovascular risk--serum lipid profiles, blood pressure, platelet stability, glucose tolerance, bioenergetics, action potential regulation--and as a life-long preventive health strategy might confer substantial benefit.

The relationship of dietary fats to prostaglandin biosynthesis

The direct and indirect evidence that the fatty acid composition of dietary fat is involved in the regulation of prostaglandin biosynthesis was reviewed. Direct evidence included effects of essential fatty acid deficiencies and excesses on endogenous tissue levels and production rates of prostaglandins by several tissues. Indirect evidence included lipolytic, platelet aggregatory, hypertensive, inflammatory and immune responses. In general, composition of dietary fat did not affect prostaglandin biosynthesis unless a biochemical essential fatty acid deficiency was induced or the linoleate to saturated fatty acids ratio of the dietary fat was greater than 5. Most results were interpreted in light of changing fatty acid composition; however, very few direct measurements have been made.

Prostaglandin production and lipolysis in isolated rat adipocytes as affected by dietary fat

The influence of dietary fat on prostaglandin production and lipolysis was tested in basal and norepinephrine stimulated adipocytes isolated from the epididymal fat pads of fasted rats. Seven diets varying in fat calories and polyunsaturation were utilized. No basal differences were noted for prostaglandin E2 production or lipolysis. Norepinephrine stimulated prostaglandin E2 and F2alpha production was significantly (P less than 0.01) increased with greater polyunsaturation of fat, but not by increased fat calories. Norepinephrine stimulated lipolysis was depressed by an increase in fat calories but was unaffected by the degree of polyunsaturation of fat. This is in vitro evidence against the concept that prostaglandins play a feedback regulator role in fat cell lipolysis since no correlation could be made between the two parameters.