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1.
Nutrients ; 14(1)2021 Dec 23.
Article in English | MEDLINE | ID: mdl-35010917

ABSTRACT

Citrulline (CIT) and nitrate-rich beetroot extract (BR) are ergogenic aids and nitric oxide (NO) precursors. In addition, both supplements seem to have other actions at the level of muscle metabolism that can benefit strength and aerobic power performance. Both supplements have been studied in numerous investigations in isolation. However, scientific evidence combining both supplements is scarce, and to the best of the authors' knowledge, there is no current study of endurance athletes. Therefore, the main purpose of this study was to determine the effect of 9 weeks of CIT plus BR supplementation on maximal and endurance-strength performance and aerobic power in male triathletes. This study was a randomized double-blind, placebo-controlled trial where participants (n = 32) were randomized into four different groups: placebo group (PLG; n = 8), CIT plus BR group (CIT- BRG; 3 g/kg/day of CIT plus 3 mg/kg/day of nitrates (NO3-); n = 8), CIT group (CITG; 3 g/kg/day; n = 8) and BR group (BRG; 3 mg/kg/day of NO3-; n = 8). Before (T1) and after 9 weeks (T2), four physical condition tests were carried out in order to assess sport performance: the horizontal jump test (HJUMP), handgrip dynamometer test, 1-min abdominal tests (1-MAT) and finally, the Cooper test. Although, no significant interactions (time × supplementation groups) were found for the strength tests (p > 0.05), the CIT- BRG supplementation presented a trend on HJUMP and 1-MAT tests confirmed by significant increase between two study moments in CIT-BRG. Likewise, CIT-BRG presented significant interactions in the aerobic power test confirmed by this group's improve estimated VO2max during the study with respect to the other study groups (p = 0.002; η2p = 0.418). In summary, supplementing with 3 g/day of CIT and 2.1 g/day of BR (300 mg/day of NO3-) for 9 weeks could increase maximal and endurance strength. Furthermore, when compared to CIT or BR supplementation alone, this combination improved performance in tests related to aerobic power.


Subject(s)
Athletes , Beta vulgaris/chemistry , Citrulline/administration & dosage , Performance-Enhancing Substances/administration & dosage , Physical Endurance , Plant Extracts/administration & dosage , Administration, Oral , Adult , Dietary Supplements , Double-Blind Method , Hand Strength , Humans , Male , Muscle, Skeletal/drug effects , Nitrates/administration & dosage , Nitrates/analysis
2.
Nutrients ; 12(5)2020 May 02.
Article in English | MEDLINE | ID: mdl-32370176

ABSTRACT

Nitric oxide related ergogenic aids such as arginine (Arg) have shown to impact positively on sport performance through several physiological and metabolic mechanisms. However, research results have shown to be controversial. The great differences regarding required metabolic pathways and physiological demands between aerobic and anaerobic sport disciplines could be the reasons. The aim of this systematic review and meta-analysis was to evaluate the effects of Arg supplementation on aerobic (≤VO2max) and anaerobic (>VO2max) performance. Likewise, to show the effective dose and timing of this supplementation. A structured search was carried out in accordance with PRISMA® (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement and PICOS guidelines in PubMed/MEDLINE, Web of Science (WOS), and Scopus databases from inception to January 2020. Eighteen studies were included which compare Arg supplementation with placebo in an identical situation and testing its effects on aerobic and anaerobic performance tests. Trials analyzing supplementation with other supplements were removed and there was not athlete's level, gender, ethnicity, or age filters. The performed meta-analysis included 15 studies and random effects model and pooled standardized mean differences (SMD) were used according to Hedges' g. Results revealed that Arg supplementation could improve aerobic (SMD, 0.84; 95% CI, 0.12 to 1.56; magnitude of SMD (MSMD), large; I2, 89%; p = 0.02) and anaerobic (SMD, 0.24; 95% CI, 0.05 to 0.43; MSMD, small; I2, 0%; p = 0.01) performance tests. In conclusion, acute Arg supplementation protocols to improve aerobic and anaerobic performance should be adjusted to 0.15 g/kg of body weight ingested between 60-90 min before. Moreover, chronic Arg supplementation should include 1.5-2 g/day for 4-7 weeks in order to improve aerobic performance, and 10-12 g/day for 8 weeks to enhance anaerobic performance.


Subject(s)
Arginine/administration & dosage , Arginine/pharmacology , Athletic Performance , Dietary Supplements , Energy Metabolism/drug effects , Performance-Enhancing Substances/administration & dosage , Performance-Enhancing Substances/pharmacology , Aerobiosis , Anaerobiosis , Body Weight , Female , Humans , Male , Nitric Oxide/metabolism
3.
J Immigr Minor Health ; 22(1): 110-119, 2020 Feb.
Article in English | MEDLINE | ID: mdl-30810968

ABSTRACT

In Mexico, tattooed migrants face discrimination and are at high-risk of incarceration, thus, we assessed whether receiving laser tattoo removal affected the likelihood of incarceration. In 2015-2016, 89 adults ages ≥ 18 years with visible tattoos were recruited at a free-clinic to receive laser tattoo removal or assigned to the wait-list; all completed baseline and 6-month questionnaires. Overall, 97.8% of participants ever migrated to the USA. In multivariate analyses restricted to migrants (n = 87), those receiving laser tattoo removal [Adjusted Odds Ratio (AOR) 0.27, 95% CI 0.07-0.89] and possessing a Mexican Voting card (AOR 0.14; 95% CI 0.03-0.58) were significantly less likely than wait-list participants to be incarcerated at 6-months. Previously incarcerated participants were significantly more likely to be incarcerated at follow-up. Tattoo removal may reduce incarceration among Mexican migrants. Future studies can assess other health and social benefits of tattoo removal for migrants/deportees returning to Mexico.


Subject(s)
Low-Level Light Therapy/statistics & numerical data , Mexican Americans/statistics & numerical data , Prisoners/statistics & numerical data , Tattooing/statistics & numerical data , Transients and Migrants/statistics & numerical data , Adult , Age Factors , Female , Humans , Interpersonal Relations , Lasers, Solid-State , Male , Mexico/ethnology , Middle Aged , Sex Factors , Socioeconomic Factors , Time Factors , United States/epidemiology , Waiting Lists
4.
J Sci Food Agric ; 99(8): 4003-4010, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30723911

ABSTRACT

BACKGROUND: Fruit dips in calcium ions solutions have been shown as an effective treatment to extend strawberries (Fragaria × ananassa, Duch) quality during storage. In the present work, strawberry fruit were treated with 10 g L-1 calcium chloride solution and treatment effects on cell wall enzymes activities and the expression of encoding genes, as well as enzymes involved in fruit defense responses were investigated. RESULTS: Calcium treatment enhanced pectin methylesterase activity while inhibited those corresponding to pectin hydrolases as polygalacturonase and ß-galactosidase. The expression of key genes for strawberry pectin metabolism was up-regulated (for FaPME1) and down-regulated (for FaPG1, FaPLB, FaPLC, FaßGal1 and FaAra1) by calcium dips. In agreement, a higher firmness level and ionically-bound pectins (IBPs) amount were detected in calcium-treated fruit compared with controls. The in vitro and in vivo growth rate of fungal pathogen Botrytis cinerea was limited by calcium treatment. Moreover, the activities of polyphenol oxidases, chitinases, peroxidases and ß-1,3-glucanases were enhanced by calcium ion dips. CONCLUSION: News insights concerning the biochemical and molecular basis of cell wall preservation and resistance to fungal pathogens on calcium-treated strawberries are provided. © 2019 Society of Chemical Industry.


Subject(s)
Calcium Chloride/pharmacology , Cell Wall/drug effects , Food Preservatives/pharmacology , Fragaria/drug effects , Cell Wall/enzymology , Cell Wall/metabolism , Fragaria/enzymology , Fragaria/genetics , Fragaria/metabolism , Fruit/drug effects , Fruit/enzymology , Fruit/metabolism , Gene Expression Regulation, Plant/drug effects , Pectins/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Polygalacturonase/genetics , Polygalacturonase/metabolism , beta-Galactosidase/genetics , beta-Galactosidase/metabolism
5.
Plant Physiol Biochem ; 130: 334-344, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30053739

ABSTRACT

Modification of cell wall polymers composition and structure is one of the main factors contributing to textural changes during strawberry (Fragaria x ananassa, Duch.) fruit ripening and storage. The present study aimed to provide new data to understand the molecular basis underlying the postharvest preservation of strawberry cell wall structure by heat treatment. Ripe fruit (cv. Aroma) were heat-treated in air oven (3 h at 45 °C) and then stored 8 days at 4 °C + 2 days at 20 °C, while maintaining a set of non-treated fruit as controls. The effect of heat stress on the expression pattern of key genes controlling strawberry cell wall metabolism, as well as some enzymatic activities was investigated. The expression of genes proved to be relevant for pectin disassembly and fruit softening process (FaPG1, FaPLB, FaPLC, FaAra1, FaßGal4) were down-regulated by heat treatment, while the expression of genes being involved in the reinforcement of cell wall as pectin-methylesterase (FaPME1) and xyloglucan endo-transglycosilase (FaXTH1) was up-regulated. Total cell wall amount as well as cellulose, hemicellulose, neutral sugars and ionically and covalently bounded pectins were higher in heat-stressed fruit compared to controls, which might be related to higher firmness values. Interestingly, heat stress was able to arrest the in vitro cell wall swelling process during postharvest fruit ripening, suggesting a preservation of cell wall structure, which was in agreement with a lower growth rate of Botrytis cinerea on plates containing cell walls from heat-stressed fruit when compared to controls.


Subject(s)
Cell Wall/metabolism , Fragaria/metabolism , Fruit/metabolism , Anthocyanins/metabolism , Carboxylic Ester Hydrolases/metabolism , Cell Wall/enzymology , Fragaria/enzymology , Fruit/enzymology , Gene Expression Regulation, Plant , Genes, Plant , Glycoside Hydrolases/metabolism , Heat-Shock Response , Hot Temperature , Hydrogen-Ion Concentration , Phenols/metabolism , Polygalacturonase/metabolism , Polysaccharides/metabolism , Real-Time Polymerase Chain Reaction , Sugars/metabolism , Xylosidases/metabolism , beta-Galactosidase/metabolism
6.
Parasite ; 24: 17, 2017.
Article in English | MEDLINE | ID: mdl-28560955

ABSTRACT

During Trypanosoma cruzi infection, oxidative stress is considered a contributing factor for dilated cardiomyopathy development. In this study, the effects of astaxanthin (ASTX) were evaluated as an alternative drug treatment for Chagas disease in a mouse model during the acute infection phase, given its anti-inflammatory, immunomodulating, and anti-oxidative properties. ASTX was tested in vitro in parasites grown axenically and in co-culture with Vero cells. In vivo tests were performed in BALB/c mice (4-6 weeks old) infected with Trypanosoma cruzi and supplemented with ASTX (10 mg/kg/day) and/or nifurtimox (NFMX; 100 mg/kg/day). Results show that ASTX has some detrimental effects on axenically cultured parasites, but not when cultured with mammalian cell monolayers. In vivo, ASTX did not have any therapeutic value against acute Trypanosoma cruzi infection, used either alone or in combination with NFMX. Infected animals treated with NFMX or ASTX/NFMX survived the experimental period (60 days), while infected animals treated only with ASTX died before day 30 post-infection. ASTX did not show any effect on the control of parasitemia; however, it was associated with an increment in focal heart lymphoplasmacytic infiltration, a reduced number of amastigote nests in cardiac tissue, and less hyperplasic spleen follicles when compared to control groups. Unexpectedly, ASTX showed a negative effect in infected animals co-treated with NFMX. An increment in parasitemia duration was observed, possibly due to ASTX blocking of free radicals, an anti-parasitic mechanism of NFMX. In conclusion, astaxanthin is not recommended during the acute phase of Chagas disease, either alone or in combination with nifurtimox.


Subject(s)
Chagas Disease/drug therapy , Trypanocidal Agents/therapeutic use , Trypanosoma cruzi/drug effects , Animals , Chlorocebus aethiops , Disease Models, Animal , Drug Therapy, Combination , Female , Heart/parasitology , Malondialdehyde/blood , Mice , Mice, Inbred BALB C , Myocardium/pathology , Nifurtimox/pharmacology , Nifurtimox/therapeutic use , Nifurtimox/toxicity , Organ Size , Parasitemia , Spleen/parasitology , Spleen/pathology , Trypanocidal Agents/pharmacology , Trypanocidal Agents/toxicity , Vero Cells/drug effects , Xanthophylls/pharmacology , Xanthophylls/therapeutic use , Xanthophylls/toxicity
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