Hormonal response to L-arginine supplementation in physically active individuals

Background: Nutritional supplements based on the amino acid L-arginine have been hypothesized to improve exercise performance by increasing levels of insulin and growth hormone (GH). Changes of these parameters in response to L-arginine supplementation may clarify the mechanisms underlying its putative physiological effects on physical performance. Objective: The aim of the study was to evaluate the effect of L-arginine supplementation on serum insulin, GH, Growth Factor Insulin-like (IGF-1), and cortisol in response to exercise. Exercise performance was also evaluated. Design: Fifteen trained runners were divided into groups supplemented with 6 g of L-arginine (ARG) or placebo (PLA). Blood samples were collected before supplementation (T0), immediately after the first exercise session (T1), after the second exercise session (T2), and after 20 min of rest (T3). The exercise consisted of two bouts of 5 km time-trial running test. Results: There was a significant increase in serum GH (T0: 3.28±0.95 vs. 3.21±0.5 ng/mL; T1: 4.35±0.23 vs. 4.17±0.13 ng/mL; T2: 4.22±0.25 vs. 4.17±0.09 ng/mL; T3: 4.14±0.29 vs. 4.13±0.18 ng/mL) and cortisol (T0: 198.71±53.77 vs. 207.57±69.51 nmol/L; T1: 458.16±116.12 vs. 433.26±101.77 nmol/L; T2: 454.61±125.21 vs. 431.88±74.82 nmol/L; T3: 311.14±102.91 vs. 362.26±110.42 nmol/L) after T1, T2, and T3, with no significant difference between the ARG and PLA groups, respectively. There was also no significant difference observed in the variables of IGF-1, insulin, and total running time between the ARG and PLA groups. Conclusions: The supplementation of L-arginine did not appear to stimulate the production of insulin, GH, and IGF-1 and, thus, provided no benefit in hormonal response or exercise performance in trained runners

Association between Femoral Artery Flow-Mediated Dilation and Muscle Oxygen Saturation Parameters in Healthy, Young Individuals

Flow-mediated dilation (FMD) and muscle oxygen saturation (StO2) are measurements utilized to assess macro- and microvascular function, respectively. Macro- and microvascular dysfunction may occur differently depending on the clinical condition. Since microvascular responsiveness can influence upstream conduit artery hemodynamics, the present study aimed to investigate whether a correlation between FMD and muscle StO2 parameters exists. Sixteen healthy, young individuals were enrolled in this study. Femoral artery FMD and tibial anterior muscle StO2 were evaluated by ultrasound and near-infrared spectroscopy, respectively. The FMD and muscle StO2 parameters were assessed by employing a vascular occlusion test (VOT). The oxygen resaturation rate was determined by calculating the upslope of StO2 immediately after occlusion and the magnitude of reperfusion as the difference between the highest and lowest StO2 value achieved during the reperfusion phase. The oxygen desaturation rate and the magnitude of desaturation during the VOT were also evaluated. A significant correlation between the FMD and oxygen resaturation rate (r = 0.628; p = 0.009), magnitude of reperfusion (r = 0.568; p = 0.022), oxygen desaturation rate (r = −0.509; p = 0.044), and magnitude of desaturation (r = 0.644; p = 0.007) was observed. This study demonstrated a moderate association between the femoral artery FMD and tibial anterior StO2 parameters in young individuals

Physicochemical, nutritional, and sensory analyses of a nitrate-enriched beetroot gel and its effects on plasmatic nitric oxide and blood pressure

Background: Beetroot (Beta vulgaris L.) is a dietary source of natural antioxidants and inorganic nitrate (NO3–). It is well known that the content of antioxidant compounds and inorganic nitrate in beetroot can reduce blood pressure (BP) and the risk of adverse cardiovascular effects. Objective: The aim of the present study was to formulate a beetroot gel to supplement dietary nitrate and antioxidant compounds able to cause beneficial health effects following acute administration. Design and subjects: A beetroot juice produced from Beta vulgaris L., without any chemical additives, was used. The juice was evaluated by physicochemical and microbiological parameters. The sample was tested in five healthy subjects (four males and one female), ingesting 100 g of beetroot gel. Results: The formulated gel was nitrate enriched and contained carbohydrates, fibers, saponins, and phenolic compounds. The formulated gels possess high total antioxidant activity and showed adequate rheological properties, such as high viscosity and pleasant texture. The consumer acceptance test for flavor, texture, and overall acceptability of beetroot gel flavorized with synthetic orange flavor had a sensory quality score >6.6. The effects of acute inorganic nitrate supplementation on nitric oxide production and BP of five healthy subjects were evaluated. The consumption of beetroot gel increased plasma nitrite threefold after 60 min of ingestion and decreased systolic BP (−6.2 mm Hg), diastolic BP (−5.2 mm Hg), and heart rate (−7 bpm)

Antimicrobial and anti-inflammatory activities of Apis mellifera honey on the Helicobacter pylori infection of Wistar rats gastric mucosa

Abstract Considering that Helicobacter pylori, a bacterium able to colonize the upper gastrointestinal tract and cause mucosal injury, not always can be effectively eradicated by the traditional approaches, there is an interest in alternative therapies until a vaccine be available. Honey is a food supplement with high carbohydrate content and antioxidant activity, as well as broad antimicrobial spectrum. After analyzing the physicochemical and in vitro antimicrobial properties of an Apis mellifera honey from the Atlantic forest of Alagoas / Brazil, the purpose of the present work was evaluate its in vivo effects against Helicobacter pylori in the gastric mucosa of Wistar rats. First, it was verified the success of inoculation/infection of the pathogen in the gastric mucosa of the rats, through the subsequent removal of their stomachs for histological analysis (hematoxylin and eosin stain and Giemsa stain). Then, four groups of animals were treated with sterilized distilled deionized water, the Apis mellifera honey, a combination of omeprazole, amoxicillin and clarithromycin, and an association of such medicines and honey (1:1). Except the control, all treatments were effective in combating infection, however, honey reduced the inflammatory process, whilst the antibiotics increase the number of eosinophils

Antimicrobial and anti-inflammatory activities of Apis mellifera honey on the Helicobacter pylori infection of Wistar rats gastric mucosa

<div><p>Abstract Considering that Helicobacter pylori, a bacterium able to colonize the upper gastrointestinal tract and cause mucosal injury, not always can be effectively eradicated by the traditional approaches, there is an interest in alternative therapies until a vaccine be available. Honey is a food supplement with high carbohydrate content and antioxidant activity, as well as broad antimicrobial spectrum. After analyzing the physicochemical and in vitro antimicrobial properties of an Apis mellifera honey from the Atlantic forest of Alagoas / Brazil, the purpose of the present work was evaluate its in vivo effects against Helicobacter pylori in the gastric mucosa of Wistar rats. First, it was verified the success of inoculation/infection of the pathogen in the gastric mucosa of the rats, through the subsequent removal of their stomachs for histological analysis (hematoxylin and eosin stain and Giemsa stain). Then, four groups of animals were treated with sterilized distilled deionized water, the Apis mellifera honey, a combination of omeprazole, amoxicillin and clarithromycin, and an association of such medicines and honey (1:1). Except the control, all treatments were effective in combating infection, however, honey reduced the inflammatory process, whilst the antibiotics increase the number of eosinophils.</p></div

12,500+ and counting: biodiversity of the Brazilian Pampa

Knowledge on biodiversity is fundamental for conservation strategies. The Brazilian Pampa region, located in subtropical southern Brazil, is neglected in terms of conservation, and knowledge of its biodiversity is fragmented. We aim to answer the question: how many, and which, species occur in the Brazilian Pampa? In a collaborative effort, we built species lists for plants, animals, bacteria, and fungi that occur in the Brazilian Pampa. We included information on distribution patterns, main habitat types, and conservation status. Our study resulted in referenced lists totaling 12,503 species (12,854 taxa, when considering infraspecific taxonomic categories [or units]). Vascular plants amount to 3,642 species (including 165 Pteridophytes), while algae have 2,046 species (2,378 taxa) and bryophytes 316 species (318 taxa). Fungi (incl. lichenized fungi) contains 1,141 species (1,144 taxa). Animals total 5,358 species (5,372 taxa). Among the latter, vertebrates comprise 1,136 species, while invertebrates are represented by 4,222 species. Our data indicate that, according to current knowledge, the Pampa holds approximately 9% of the Brazilian biodiversity in an area of little more than 2% of Brazil’s total land. The proportion of species restricted to the Brazilian Pampa is low (with few groups as exceptions), as it is part of a larger grassland ecoregion and in a transitional climatic setting. Our study yielded considerably higher species numbers than previously known for many species groups; for some, it provides the first published compilation. Further efforts are needed to increase knowledge in the Pampa and other regions of Brazil. Considering the strategic importance of biodiversity and its conservation, appropriate government policies are needed to fund studies on biodiversity, create accessible and constantly updated biodiversity databases, and consider biodiversity in school curricula and other outreach activities