Effects of an L-arginine-based multi ingredient product on endothelial function in subjects with mild to moderate hypertension and hyperhomocysteinemia - a randomized, double-blind, placebo-controlled, cross-over trial.

BACKGROUND: Nutrition plays an important role in prevention and management of cardiovascular diseases (CVD) in early stages. Recent research demonstrated beneficial effects of various nutritional ingredients on vascular health. The aim of the current study was to evaluate the effects of an L-arginine-based multi ingredient product (AbMIP) on vascular function. METHODS: Twenty-five male and female subjects, aged between 45 and 65 years with elevated blood pressure and hyperhomocysteinemia were included in this cross-over trial. Subjects were randomly assigned to one of the two sequence groups (AbMIP -placebo or placebo - AbMIP). AbMIP and placebo were taken for 4 weeks, each. Endothelial function under fasting conditions, blood pressure, postprandial endothelial function after consumption of a high fat meal, homocysteine, asymmetric dimethyl arginine (ADMA) and Hba1c were determined. RESULTS: AbMIP significantly improved fasting endothelial function determined by EndoPAT™ when compared to placebo (p = 0.047). Similarly, homocysteine levels were significantly decreased after verum supplementation when compared to placebo (p < 0.0001). Systolic blood pressure decreased significantly under AbMIP (p = 0.002) and the reduction was more pronounced when compared to placebo. However, due to placebo-effects no significant difference could be found between groups (p = 0.586). The effects on postprandial endothelial function were stronger for AbMIP when compared with placebo but did not reach significance (p = 0.201). No significant effects of AbMIP were observed regarding HbA1c, ADMA and diastolic blood pressure. CONCLUSIONS: Due to improvement on endothelial function, decrease of elevated homocysteine levels and excellent tolerability, AbMIP was demonstrated to be a beneficial option for dietary treatment of endothelial dysfunction and hyperhomocysteinemia in early stages of CVD. TRIAL REGISTRATION: The clinical trials.gov identifier is NCT02392767 , November 14, 2014.

Reduced muscular fatigue after a 12-week leucine-rich amino acid supplementation combined with moderate training in elderly: a randomised, placebo-controlled, double-blind trial.

BACKGROUND: Age-related muscle loss is characterised by a progressing decrease in muscle mass, strength and function. Besides resistance training and physical activity, appropriate nutrition that is rich in protein, especially branched-chain amino acids, is very important to support training effects and positively influence the protein synthesis to degradation ratio. AIM: The purpose of this study was to evaluate the effect of a 12-week leucine-rich amino acid supplementation in combination with moderate training. METHODS: Forty-eight healthy subjects exercised for 30 min three times per week and received either a leucine-rich amino acid supplementation or a placebo. Before and after supplementation, volunteers performed an exhaustive eccentric exercise protocol. Maximal concentric strength, muscle soreness, creatine kinase (CK), type II collagen collagenase cleavage neoepitope (C2C), C propeptide of type II procollagen (CP2) and safety assessments were performed before exercise and after 3, 24, 48 and 72 hours. RESULTS: The supplementation with leucine resulted in reduced loss of strength at 0 and 3 hours after downhill walking compared with the placebo (p=0.0439). The reduction of C2C/CP2 ratio deflection was significantly increased (p=0.038) due to leucine compared with the placebo. The same tendency could be observed for the recovery phase. No significant supplement effects for muscle soreness and CK could be observed. CONCLUSION: The principle findings show that leucine-rich amino acid supplementation can counteract the negative effects of eccentric exercise. The treatment resulted in a reduction of exercise-induced strength loss.

Spatial orientation of the subtalar joint axis is different in subjects with and without Achilles tendon disorders.

BACKGROUND: There are many possible predisposing factors for Achilles tendon disorders suggested in the literature but their pathogenetic relevance is not proven in most cases. The asymmetric mechanical load distribution within the Achilles tendon during locomotion is frequently addressed as a major risk factor for Achilles tendon disorders. The spatial orientation of the subtalar joint axis (STA) may influence the Achilles tendon loading possibly leading to overload injuries. Hypothesis There is a significant difference between the orientation of the STA in subjects with and without Achilles tendon pathologies. MATERIALS AND METHODS: 614 subtalar joint axes determined in 307 long-distance runners with and without Achilles tendon disorders were included. Achilles tendon disorders were defined as any Achilles tendon-related pain during or following running, existing for more than 2 weeks in the past. Motion analysis of the foot was performed using an ultrasonic pulse-echo-based measurement system. The orientation of the STA was expressed by two angles. RESULTS: The mean inclination angle was 42 ± 16° and the mean deviation angle was 11 ± 2 3°. There was a significant difference (p=0.002) between the mean deviation angle measured in subjects with Achilles tendon pathologies (18 ± 23°) and those without (10 ± 23°). CONCLUSIONS: The results demonstrate a wide interindividual variability of the spatial orientation of the STA. In addition, the mean deviation angle in people with Achilles tendon pathologies is significantly more oblique than in people without. This finding indicates that the spatial orientation of the STA is related to the incidence of overuse injuries of the Achilles tendon in the investigated sample.