linoleic-acid and Pneumonia

Alterations in arachidonic acid (AA) metabolism have been reported to occur in diabetes mellitus. The present study was carried out to verify if these alterations are due to the relative lack of insulin or to high levels of blood glucose. Male Wistar rats were rendered diabetic by alloxan injection (42 mg/kg, i.v.), 10 or 30 days before the experiments. Some diabetic rats received a single dose (4 IU, s.c.) of NPH insulin 2 h before an intratracheal instillation of lipopolysaccharide (LPS, 750 microg) or saline. Six hours after LPS challenge, the following parameters were analysed: blood glucose levels, total and differential leukocyte counts in bronchoalveolar lavage (BAL) fluid; linoleic acid and AA content in blood neutrophils (HPLC), and levels of prostaglandin (PG)E(2) in BAL (ELISA). Relative to controls, a reduced number of neutrophils (18%) and decreased amounts of PGE(2) (40%) were observed in the BAL fluid of diabetic rats in response to LPS. A single dose of insulin was not able to reduce blood sugar levels to normal values, but instead resulted in the normalization of both leukocyte migration to the lungs and levels of PGE(2). Accordingly, these abnormalities might be primarily linked to a continuing insulin deficiency rather than to secondary hyperglycaemia occurring in the diabetic rat. In conclusion, data presented suggest that insulin might regulate neutrophil migration and generation of PGE(2) during the course of acute lung injury induced by LPS.

Topics: Alloxan; Animals; Arachidonic Acid; Bronchoalveolar Lavage Fluid; Cyclooxygenase 2; Diabetes Mellitus, Experimental; Dinoprostone; Insulin; Linoleic Acid; Lipopolysaccharides; Male; Neutrophils; Pneumonia; Rats; Rats, Wistar

Essential fatty acids modulate inflammation and glucose metabolism and may alter infection risk.. We examined the association between intakes of n-6 and n-3 fatty acids and fish and the risk of community-acquired pneumonia.. We prospectively evaluated 38,378 male US health professionals aged 44-79 y at the outset. We updated medical and lifestyle information biennially through questionnaires and diet every 4 y with the use of a validated food-frequency questionnaire. We excluded men who reported pneumonia, myocardial infarction, stroke, other heart disease, arterial surgery, cancer, or asthma before 1990 or those with incomplete dietary data. Community-acquired pneumonia was determined by blinded medical record review of chest radiographs.. During 10 y of follow-up, there were 441 new cases of nonfatal community-acquired pneumonia. Pneumonia risk was lower in men in the highest energy-adjusted quintiles of intake than in men in the lowest quintiles of intake of linoleic acid [multivariate relative risk (RR): 0.70; 95% CI: 0.51, 0.96; P for trend = 0.01] and alpha-linolenic acid (multivariate RR: 0.68; 95% CI: 0.50, 0.93; P for trend = 0.01). Pneumonia risk decreased 4% for every 1-g/d increase in linoleic acid intake (multivariate RR: 0.96; 95% CI: 0.93, 0.99). Pneumonia risk was reduced by 31% for every 1-g/d increase in alpha-linolenic acid intake (multivariate RR: 0.69; 95% CI: 0.51, 0.93). Intakes of eicosapentaenoic acid and docosahexaenoic acid were not significantly related to pneumonia risk.. Higher intakes of alpha-linolenic and linoleic acids and possibly of fish may reduce the risk of pneumonia.

Topics: Adult; Aged; alpha-Linolenic Acid; Animals; Cohort Studies; Community-Acquired Infections; Confidence Intervals; Diet Surveys; Dietary Fats, Unsaturated; Fatty Acids, Omega-3; Fatty Acids, Omega-6; Fishes; Follow-Up Studies; Humans; Incidence; Life Style; Linoleic Acid; Male; Middle Aged; Multivariate Analysis; Pneumonia; Prospective Studies; Risk Factors; Surveys and Questionnaires; United States

Topics: Aspartic Acid; Child, Preschool; Humans; Infant; Linoleic Acid; Linoleic Acids; Pneumonia; Potassium Magnesium Aspartate