Objective: To determine whether fish oil supplementation (primary objective) or aspirin use (secondary objective) is effective in reducing arteriovenous fistula failure.
Design, Setting, and Participants: The Omega-3 Fatty Acids (Fish Oils) and Aspirin in Vascular Access Outcomes in Renal Disease (FAVOURED) study was a randomized, double-blind, controlled clinical trial that recruited participants with stage 4 or 5 chronic kidney disease from 2008 to 2014 at 35 dialysis centers in Australia, Malaysia, New Zealand, and the United Kingdom. Participants were observed for 12 months after arteriovenous fistula creation.
Interventions: Participants were randomly allocated to receive fish oil (4 g/d) or matching placebo. A subset (n = 406) was also randomized to receive aspirin (100 mg/d) or matching placebo. Treatment started 1 day prior to surgery and continued for 12 weeks.
Main Outcomes and Measures: The primary outcome was fistula failure, a composite of fistula thrombosis and/or abandonment and/or cannulation failure, at 12 months. Secondary outcomes included the individual components of the primary outcome.
Results: Of 1415 eligible participants, 567 were randomized (359 [63%] male, 298 [53%] white, 264 [47%] with diabetes; mean [SD] age, 54.8 [14.3] y). The same proportion of fistula failures occurred in the fish oil and placebo arms (128 of 270 [47%] vs 125 of 266 [47%]; relative risk [RR] adjusted for aspirin use, 1.03; 95% CI, 0.86-1.23; P = .78). Fish oil did not reduce fistula thrombosis (60 [22%] vs 61 [23%]; RR, 0.98; 95% CI, 0.72-1.34; P = .90), abandonment (51 [19%] vs 58 [22%]; RR, 0.87; 95% CI, 0.62-1.22; P = .43), or cannulation failure (108 [40%] vs 104 [39%]; RR, 1.03; 95% CI, 0.83-1.26; P = .81). The risk of fistula failure was similar between the aspirin and placebo arms (87 of 194 [45%] vs 83 of 194 [43%]; RR, 1.05; 95% CI, 0.84-1.31; P = .68).
Conclusions and Relevance: Neither fish oil supplementation nor aspirin use reduced failure of new arteriovenous fistulae within 12 months of surgery.
Trial Registration: anzctr.org.au Identifier: CTRN12607000569404.
PRACTICAL APPLICATION: Kenaf seed oil-in-water nanoemulsion (KSON) has the potential to be used as a natural alternative to the synthetic hypocholesterolemic drug in the future. However, larger sample size and clinical trial are needed to confirm on this potential application. In addition, treatment with KSON was suggested to prevent cardiovascular disease and fatty liver.
METHODS: Palm kernel oil esters (PKOEs)-based nanoemulsions were loaded with P. urinaria extract using a spontaneous method and characterized with respect to particle size, zeta potential, and rheological properties. The release profile of the extract was evaluated using in vitro Franz diffusion cells from an artificial membrane and the antioxidant activity of the extract released was evaluated using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) method.
RESULTS: Formulation F12 consisted of wt/wt, 0.05% P. urinaria extract, 1% cetyl alcohol, 0.5% glyceryl monostearate, 12% PKOEs, and 27% Tween 80/Span 80 (9/1) with a hydrophilic lipophilic balance of 13.9, and a 59.5% phosphate buffer system at pH 7.4. Formulation F36 was comprised of 0.05% P. urinaria extract, 1% cetyl alcohol, 1% glyceryl monostearate, 14% PKOEs, 28% Tween 80/Span 80 (9/1) with a hydrophilic lipophilic balance of 13.9, and 56% phosphate buffer system at pH 7.4 with shear thinning and thixotropy. The droplet size of F12 and F36 was 30.74 nm and 35.71 nm, respectively, and their nanosizes were confirmed by transmission electron microscopy images. Thereafter, 51.30% and 51.02% of the loaded extract was released from F12 and F36 through an artificial cellulose membrane, scavenging 29.89% and 30.05% of DPPH radical activity, respectively.
CONCLUSION: The P. urinaria extract was successfully incorporated into a PKOEs-based nanoemulsion delivery system. In vitro release of the extract from the formulations showed DPPH radical scavenging activity. These formulations can neutralize reactive oxygen species and counteract oxidative injury induced by ultraviolet radiation and thereby ameliorate skin aging.
METHODS: Animals were divided into three groups: (i) normal non-diabetic (NDM), (ii) diabetic treated (tocotrienol-rich fractions - TRF) and (iii) diabetic untreated (non-TRF). The treatment group received oral administration of tocotrienol-rich fractions (200 mg/kg body weight) daily for eight weeks. The normal non-diabetic and the diabetic untreated groups were fed standard rat feed. Blood glucose and lipid profiles, oxidative stress markers and morphological changes of the thoracic aorta were evaluated.
RESULTS: Tocotrienol-rich fractions treatment reduced serum glucose and glycated hemoglobin concentrations. The tocotrienol-rich fractions group also showed significantly lower levels of plasma total cholesterol, low-density lipoprotein cholesterol, and triglyceride, as compared to the untreated group. The tocotrienol-rich fractions group had higher levels of high-density lipoprotein cholesterol, as compared to the untreated group. Superoxide dismutase activity and levels of vitamin C in plasma were increased in tocotrienol-rich fractions-treated rats. The levels of plasma and aorta malondealdehyde + 4-hydroxynonenal (MDA + 4-HNE) and oxidative DNA damage were significant following tocotrienol-rich fractions treatment. Electron microscopic examination showed that the normal morphology of the thoracic aorta was disrupted in STZ-diabetic rats. Tocotrienol-rich fractions supplementation resulted in a protective effect on the vessel wall.
CONCLUSION: These results show that tocotrienol-rich fractions lowers the blood glucose level and improves dyslipidemia. Levels of oxidative stress markers were also reduced by administration of tocotrienol-rich fractions. Vessel wall integrity was maintained due to the positive effects mediated by tocotrienol-rich fractions.
METHODS: Adult male Sprague-Dawley rats were divided into 11 groups; the control group was fed with rat chow, and the other groups were fed with chow that was mixed with 15% weight/weight palm or soy oils, which were either in a fresh form or heated once, twice, five, or ten times. Blood pressures were measured at the baseline and throughout the 24-week study. Plasma nitric oxide levels were assessed prior to treatment and at the end of the study. Following 24 weeks, the rats were sacrificed to investigate their vascular reactivity using the thoracic aorta.
RESULTS: Palm and soy oils had no detrimental effects on blood pressure, and they significantly elevated the nitric oxide contents and reduced the contractile responses to phenylephrine. However, trials using palm and soy oils that were repeatedly heated showed an increase in blood pressure, enhanced phenylephrine-induced contractions, reduced acetylcholine- and sodium nitroprusside-induced relaxations relative to the control and rats that were fed fresh vegetable oils.
CONCLUSIONS: The blood pressure-raising effect of the heated vegetable cooking oils is associated with increased vascular reactivity and a reduction in nitric oxide levels. The chronic consumption of heated vegetable oils leads to disturbances in endogenous vascular regulatory substances, such as nitric oxide. The thermal oxidation of the cooking oils promotes the generation of free radicals and may play an important contributory role in the pathogenesis of hypertension in rats.