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1.
Nutrients ; 16(11)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38892699

RESUMO

BACKGROUND: Maintaining adequate hydration is critical to optimal health, well-being, and performance. Those who are physically active in stressful environments, such as warm and/or humid scenarios, may be at particular risk for dehydration with ensuing loss of electrolytes, leading to sluggishness and impaired physical performance. METHODS: We evaluated an electrolyte and amino acid product containing L-alanine and L-glutamine, as well as select vitamins [B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B12 (cobalamin), and vitamin C (ascorbic acid)]. Subjects (n = 40; four groups, n = 10) were randomized to consume either a placebo packet or one, two, or three packets daily of the test product for 4 weeks with site visits at 0, 2, and 4 weeks. We tested safety and tolerability by analyzing hematological parameters (complete blood counts), metabolic parameters (hepatic, renal, acid-base balance), urinalysis end products, thyroid status [T3 (triiodothyronine), T4 (thyroxine), TSH (thyroid-stimulating hormone)], tolerability (via questionnaire), vital signs, and dietary intake. RESULTS: Statistical analyses displayed ten significant main effects (p < 0.05) with white blood cells, lymphocytes, neutrophils, urinary pH, thyroxine, urination frequency, calcium, calories, fat, and cholesterol. Interactions for time and group (p < 0.05) were observed for MCV, eGFR, potassium, overall tolerability, bloating, and cramping-demonstrating mild GA disturbances. Little to no change of physiological relevance was noted for any outcome variable, regardless of dosing level. CONCLUSIONS: Our results indicate the product was well-tolerated at all dosing levels and no significant adverse changes occurred in any of the test parameters compared to the placebo group, indicating relative safety of ingestion over a 4-week treatment period, at the volumes used, and outside the context of physical stress.


Assuntos
Aminoácidos , Humanos , Feminino , Masculino , Adulto , Aminoácidos/sangue , Bebidas , Adulto Jovem , Desidratação , Método Duplo-Cego , Pessoa de Meia-Idade , Eletrólitos , Vitaminas/administração & dosagem , Equilíbrio Hidroeletrolítico/efeitos dos fármacos
2.
Cureus ; 16(3): e55661, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38590496

RESUMO

Objective This study aimed to assess the impact of acute and short-term supplementation with NAD3®, a theacrine-containing supplement, on circulating adult stem cell numbers in a healthy male and female population aged 40-70 years. Methods This was a double-blind, placebo-controlled crossover study with 12 participants randomized to receive either NAD3® or a placebo for seven days. Blood samples were collected after an overnight fast, before and after the seven-day supplementation period, and one and two hours after the final supplement dose. Using flow cytometry, circulating stem cells, including lymphocytoid CD34+ stem cells (CD45dimCD34+), stem cells associated with vascular maintenance and repair (CD45dimCD34+CD309+), CD34+ stem cells linked to a progenitor phenotype (CD45dimCD34+CD309neg), circulating endothelial stem cells (CD45negCD31+CD309+), and mesenchymal stem cells (CD45negCD90+) were quantified. Results Acute NAD3® supplementation did not result in the mobilization of stem cells from the bone marrow. However, seven days of daily NAD3® supplementation resulted in selective changes in circulating stem cell numbers. A significant time*treatment interaction was observed for CD45dimCD34+ cells (p=0.04) and CD45dimCD34+CD309neg cells (p=0.04), indicating a decrease in cell numbers with supplementation. There was also a trend toward an increase in circulating endothelial cells (p=0.08) with seven days of NAD3®supplementation. Conclusion Short-term NAD3® supplementation demonstrated an effect on the quantity of bone marrow-derived stem cells in circulation. The study suggests that this theacrine-containing supplement may play a role in modulating adult stem cell populations, emphasizing the potential impact of NAD3® on regenerative processes. Further research with extended supplementation periods and larger sample sizes is warranted to elucidate the functional consequences of these changes and explore the therapeutic implications for age-related declines in stem cell function.

3.
BMC Biochem ; 13: 4, 2012 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-22305293

RESUMO

BACKGROUND: Bird species show a high degree of variation in the composition of their preen gland waxes. For instance, galliform birds like chicken contain fatty acid esters of 2,3-alkanediols, while Anseriformes like goose or Strigiformes like barn owl contain wax monoesters in their preen gland secretions. The final biosynthetic step is catalyzed by wax synthases (WS) which have been identified in pro- and eukaryotic organisms. RESULTS: Sequence similarities enabled us to identify six cDNAs encoding putative wax synthesizing proteins in chicken and two from barn owl and goose. Expression studies in yeast under in vivo and in vitro conditions showed that three proteins from chicken performed WS activity while a sequence from chicken, goose and barn owl encoded a bifunctional enzyme catalyzing both wax ester and triacylglycerol synthesis. Mono- and bifunctional WS were found to differ in their substrate specificities especially with regard to branched-chain alcohols and acyl-CoA thioesters. According to the expression patterns of their transcripts and the properties of the enzymes, avian WS proteins might not be confined to preen glands. CONCLUSIONS: We provide direct evidence that avian preen glands possess both monofunctional and bifunctional WS proteins which have different expression patterns and WS activities with different substrate specificities.


Assuntos
Aciltransferases/genética , Proteínas Aviárias/genética , Galinhas/genética , Gansos/genética , Estrigiformes/genética , Aciltransferases/química , Aciltransferases/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Proteínas Aviárias/química , Proteínas Aviárias/metabolismo , Membrana Celular/enzimologia , Galinhas/metabolismo , Glândulas Exócrinas/enzimologia , Perfilação da Expressão Gênica , Lipídeos/biossíntese , Dados de Sequência Molecular , Especificidade de Órgãos , Filogenia , Saccharomyces cerevisiae , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
4.
Lipids ; 47(4): 371-81, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22160552

RESUMO

Multifunctional acyltransferases are able to catalyze the esterification of various acyl-acceptors with activated fatty acids. Here we describe the identification of four proteins from Tetrahymena thermophila that share certain properties with mammalian acyltransferases regarding their predicted transmembrane structure, their molecular mass and the typical acyltransferase motif. Expression of the Tetrahymena sequences results in production of triacylglycerols and wax esters in recombinant yeast when appropriate substrates are provided. The in vitro characterization shows, that these enzymes are capable of esterifying different acyl-acceptors including fatty alcohols, diols, diacylglycerols and isoprenols with acyl-CoA thioesters. Based on these catalytic activities and the sequence similarities of the Tetrahymena proteins with acyl-CoA:diacylglycerol acyltransferase 2 (DGAT2) family members, we conclude that we identified a new group of DGAT2-related multifunctional acyltransferases from protozoan organisms.


Assuntos
Aciltransferases/metabolismo , Proteínas de Protozoários/metabolismo , Tetrahymena thermophila/enzimologia , Triglicerídeos/biossíntese , Aciltransferases/química , Aciltransferases/genética , Sequência de Aminoácidos , Clonagem Molecular , Ésteres/metabolismo , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Dados de Sequência Molecular , Filogenia , Estrutura Terciária de Proteína , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Especificidade por Substrato , Tetrahymena thermophila/genética , Ceras/metabolismo
5.
BMC Biochem ; 12: 64, 2011 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-22151413

RESUMO

BACKGROUND: Birds clean and lubricate their feathers with waxes that are produced in the uropygial gland, a holocrine gland located on their back above the tail. The type and the composition of the secreted wax esters are dependent on the bird species, for instance the wax ester secretion of goose contains branched-chain fatty acids and unbranched fatty alcohols, whereas that of barn owl contains fatty acids and alcohols both of which are branched. Alcohol-forming fatty acyl-CoA reductases (FAR) catalyze the reduction of activated acyl groups to fatty alcohols that can be esterified with acyl-CoA thioesters forming wax esters. RESULTS: cDNA sequences encoding fatty acyl-CoA reductases were cloned from the uropygial glands of barn owl (Tyto alba), domestic chicken (Gallus gallus domesticus) and domestic goose (Anser anser domesticus). Heterologous expression in Saccharomyces cerevisiae showed that they encode membrane associated enzymes which catalyze a NADPH dependent reduction of acyl-CoA thioesters to fatty alcohols. By feeding studies of transgenic yeast cultures and in vitro enzyme assays with membrane fractions of transgenic yeast cells two groups of isozymes with different properties were identified, termed FAR1 and FAR2. The FAR1 group mainly synthesized 1-hexadecanol and accepted substrates in the range between 14 and 18 carbon atoms, whereas the FAR2 group preferred stearoyl-CoA and accepted substrates between 16 and 20 carbon atoms. Expression studies with tissues of domestic chicken indicated that FAR transcripts were not restricted to the uropygial gland. CONCLUSION: The data of our study suggest that the identified and characterized avian FAR isozymes, FAR1 and FAR2, can be involved in wax ester biosynthesis and in other pathways like ether lipid synthesis.


Assuntos
Aldeído Oxirredutases/metabolismo , Proteínas Aviárias/metabolismo , Aves/metabolismo , Aldeído Oxirredutases/química , Aldeído Oxirredutases/genética , Sequência de Aminoácidos , Animais , Proteínas Aviárias/química , Proteínas Aviárias/genética , Aves/classificação , Aves/genética , Galinhas , Evolução Molecular , Gansos , Humanos , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Alinhamento de Sequência , Estrigiformes , Especificidade por Substrato
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