Changes in Oxidative Stress and Inflammatory Biomarkers in Fragile Adults over Fifty Years of Age and in Elderly People Exclusively Fed Enteral Nutrition.

We aim to evaluate whether exclusive feeding of an enteral formula enriched with n-3 long chain polyunsaturated fatty acids (n-3 LC-PUFA) affects oxidative stress and the antioxidant defence system and may improve the levels of some relevant inflammatory, and cardiovascular biomarkers in frail adults over fifty years of age and in elderly subjects. Fifty-five patients were divided into two groups and were exclusively fed a newly designed normoproteic and isocaloric enteral formula enriched with eicosapentaenoic (98 mg/d) and docosahexaenoic acids (46 mg/d) (n = 26) or a reference enteral diet (n = 29). Oxidative, inflammatory and cardiovascular risk biomarkers and red blood cell fatty acid profiles were determined at the beginning and after 90 and 180 days of feeding. The n-3 LC-PUFA percentage tended to be higher (P = 0.053) in the experimental group than in the reference group. Administration of the n-3 LC-PUFA diet did not increase oxidative stress or modify plasma antioxidant capacity but decreased antioxidant enzymatic activities. MMP-9 plasma concentration decreased with both formulae, whereas tPAI-1 tended to decrease (P = 0.116) with the administration of the experimental formula. In conclusion, administration of the new n-3 LC-PUFA-enriched product for 6 months did not negatively alter the oxidative status and improved some cardiovascular risk biomarkers.

Impact of nutritional status on the oral bioavailability of leucine administered to rats as part of a standard enteral diet.

BACKGROUND: To investigate the absorption and relative bioavailability of leucine administered orally as part of an enteral diet in well and malnourished animals. METHODS: Two groups - RN (regular nutrition) and PCR (protein-calorie restricted) - were fed with different diets for 23-25 days. Rats from each group were assigned randomly to one of three treatments (water, T-Diet Plus Standard(®) (problem) or Isosource ST(®) (reference)) administered in single (N = 76) or multiple (N = 39) doses. Blood samples were assayed for leucine content. Area under the curve (AUC) was calculated by non-compartmental analysis. Log-transformed AUC(s) were statistically compared by analysis of variance, and 90% confidence intervals (CI 90%) of the ratio of the log-transformed AUC(s) between problem and reference diets, and between enteral diet and water were determined. RESULTS: The AUC (last) between the problem and reference diets was not statistically different. 90% CIs for single and multiple doses were 58.4-137.5% and 78-134.6% for RN and 76.7-172.2% and 72-167.2% for PCR, respectively. Leucine absorption was 12% higher among malnourished animals when multiple doses were administered, but the differences detected were not statistically different. CONCLUSIONS: In spite of the different composition of proteins in the enteral diets tested, the absorption of leucine, even though slightly higher in the malnourished state, is similar in both of them.

Influence of an eicosapentaenoic and docosahexaenoic acid-enriched enteral nutrition formula on plasma fatty acid composition and biomarkers of insulin resistance in the elderly.

BACKGROUND & AIMS: n-3 Polyunsaturated fatty acids may improve cardiovascular outcomes in elderly. The aim of this study was to determine the effect of feeding elderly patients exclusively with an n-3 polyunsaturated fatty acid-enriched diet specifically designed for enteral nutrition for 6 months, evaluating modifications in plasma fatty acid profile and some biomarkers of insulin resistance (IR). METHODS: Thirty-two patients >65 years were fed a new enteral formula (T-Diet Plus) containing 75 mg/l of eicosapentaenoic acid (EPA) and 35 mg/l of docosahexaenoic acid (DHA) and 33 were fed an enteral diet intended for elderly (Jevity). Blood samples were drawn at the beginning and after 3 and 6 months of feeding. Plasma lipids, total plasma and lipid fraction fatty acid profiles, and some IR-associated adipokines were analysed. RESULTS: Feeding on T-Diet Plus allowed EPA and DHA incorporation into plasma lipids and normalised blood triacylglycerols (TAG) levels after 3 months without major changes in IR, leptin and adiponectin. CONCLUSIONS: Feeding the elderly exclusively with an enteral formula enriched with EPA and DHA improves their plasma lipid fatty acid profile and lowers TAG, a well known cardiovascular risk biomarker, without affecting IR.