Role of LTB4 and nitric oxide in the gastroprotective effect of Prosthechea karwinskii leaves extract in the indomethacin-induced gastric injury in the rat.

Gastric injury is mainly described by inflammation of the gastric epithelium. Recently, our group of work demonstrated that Prosthechea karwinskii leaves extract induces both an in vitro antioxidative action and an in vivo gastroprotective effect in a rat. However, the molecules involved in the gastroprotective action by Prosthechea karwinskii are not known. Thus, the aim of this study is to determine whether Prosthechea karwinskii extract modifies anti-inflammatory and antioxidative biomarkers in an in vivo rat model of indomethacin-induced gastric injury. Rats were orally administered with indomethacin and Prosthechea karwinskii leaf extract. Our results suggest that the gastroprotective effect of Prosthechea karwinskii leaf extract is related to the reduction in leukocyte infiltration and antioxidative action in a model of indomethacin-induced gastric injury. Further studies are warranted to investigate the role of the compounds identified in the gastroprotective action of Prosthechea karwinskii leaves extract.

Clinical study of the effects on asthma-related QOL and asthma management of a medical food in adult asthma patients.

BACKGROUND: Asthma can have a negative impact on quality of life although this is not well correlated with objective evaluations of pulmonary function. A medical food, EFF1009, containing the fatty acids gamma-linolenic acid (GLA) and eicosapentaenoic acid (EPA) decreases leukotriene B(4) synthesis in patients with asthma. Two previous clinical studies with EFF1009 provided preliminary evidence that the medical food improves asthma-related quality of life (ARQOL) and asthma management. OBJECTIVE: To evaluate the impact on ARQOL of EFF1009 in adults with asthma. RESEARCH DESIGN AND METHODS: The study was a randomized, prospective, double-blind, placebo-controlled, parallel group study in twenty-one (N = 21 evaluable) subjects with mild to moderate persistent asthma who consumed the medical food emulsion or placebo emulsion daily for 28 days. All participants continued their asthma medications throughout the study. ARQOL, including asthma signs and symptoms, and asthma control were measured using the Mini Asthma Quality of Life Questionnaire (MiniAQLQ) and the Asthma Control Questionnaire (ACQ), administered at baseline, Day 14 and Day 28. Safety and tolerability parameters, including adverse events, were monitored. RESULTS: Baseline ARQOL scores, forced expiratory volume in one second (FEV(1)) and other characteristics were balanced between both groups. Mean (standard error) total MiniAQLQ scores changed by 0.73 (0.38) and -0.22 (0.36) in the EFF1009 and placebo groups, respectively, (p < 0.05). The MiniAQLQ symptom domain score was improved in the EFF1009 group (p < 0.05). Total scores for the ACQ were not significantly improved in either group. Levels of the fatty acid EPA in plasma increased in the EFF1009 group but not the placebo group (p < 0.03). The medical food was well tolerated and no safety concerns were identified. CONCLUSIONS: The dietary addition of the medical food EFF1009 to asthma management regimens can improve patient perceived, ARQOL and can also improve asthma management as evidenced by reduced asthma symptoms. An additional study of the medical food, with larger subject population and longer treatment duration, is warranted to confirm these findings.

Dietary polyunsaturated fatty acids and inflammatory mediator production.

Many antiinflammatory pharmaceutical products inhibit the production of certain eicosanoids and cytokines and it is here that possibilities exist for therapies that incorporate n-3 and n-9 dietary fatty acids. The proinflammatory eicosanoids prostaglandin E(2) (PGE(2)) and leukotriene B(4) (LTB(4)) are derived from the n-6 fatty acid arachidonic acid (AA), which is maintained at high cellular concentrations by the high n-6 and low n-3 polyunsaturated fatty acid content of the modern Western diet. Flaxseed oil contains the 18-carbon n-3 fatty acid alpha-linolenic acid, which can be converted after ingestion to the 20-carbon n-3 fatty acid eicosapentaenoic acid (EPA). Fish oils contain both 20- and 22-carbon n-3 fatty acids, EPA and docosahexaenoic acid. EPA can act as a competitive inhibitor of AA conversion to PGE(2) and LTB(4), and decreased synthesis of one or both of these eicosanoids has been observed after inclusion of flaxseed oil or fish oil in the diet. Analogous to the effect of n-3 fatty acids, inclusion of the 20-carbon n-9 fatty acid eicosatrienoic acid in the diet also results in decreased synthesis of LTB(4). Regarding the proinflammatory ctyokines, tumor necrosis factor alpha and interleukin 1beta, studies of healthy volunteers and rheumatoid arthritis patients have shown < or = 90% inhibition of cytokine production after dietary supplementation with fish oil. Use of flaxseed oil in domestic food preparation also reduced production of these cytokines. Novel antiinflammatory therapies can be developed that take advantage of positive interactions between the dietary fats and existing or newly developed pharmaceutical products.