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1.
J Funct Biomater ; 14(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37754867

RESUMO

The gastrointestinal tract (GIT) environment has an intricate and complex nature, limiting drugs' stability, oral bioavailability, and adsorption. Additionally, due to the drugs' toxicity and side effects, renders are continuously seeking novel delivery systems. Lipid-based drug delivery vesicles have shown various loading capacities and high stability levels within the GIT. Indeed, most vesicular platforms fail to efficiently deliver drugs toward this route. Notably, the stability of vesicular constructs is different based on the different ingredients added. A low GIT stability of liposomes and niosomes and a low loading capacity of exosomes in drug delivery have been described in the literature. Bilosomes are nonionic, amphiphilic, flexible surfactant vehicles that contain bile salts for the improvement of drug and vaccine delivery. The bilosomes' stability and plasticity in the GIT facilitate the efficient carriage of drugs (such as antimicrobial, antiparasitic, and antifungal drugs), vaccines, and bioactive compounds to treat infectious agents. Considering the intricate and harsh nature of the GIT, bilosomal formulations of oral substances have a remarkably enhanced delivery efficiency, overcoming these conditions. This review aimed to evaluate the potential of bilosomes as drug delivery platforms for antimicrobial, antiviral, antifungal, and antiparasitic GIT-associated drugs and vaccines.

2.
Nutrients ; 15(18)2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37764715

RESUMO

The human gut microbiome, an intricate ecosystem housing trillions of microorganisms within the gastrointestinal tract, holds significant importance in human health and the development of diseases. Recent advances in technology have allowed for an in-depth exploration of the gut microbiome, shedding light on its composition and functions. Of particular interest is the role of diet in shaping the gut microbiome, influencing its diversity, population size, and metabolic functions. Precision nutrition, a personalized approach based on individual characteristics, has shown promise in directly impacting the composition of the gut microbiome. However, to fully understand the long-term effects of specific diets and food components on the gut microbiome and to identify the variations between individuals, longitudinal studies are crucial. Additionally, precise methods for collecting dietary data, alongside the application of machine learning techniques, hold immense potential in comprehending the gut microbiome's response to diet and providing tailored lifestyle recommendations. In this study, we investigated the complex mechanisms that govern the diverse impacts of nutrients and specific foods on the equilibrium and functioning of the individual gut microbiome of seven volunteers (four females and three males) with an average age of 40.9 ± 10.3 years, aiming at identifying potential therapeutic targets, thus making valuable contributions to the field of personalized nutrition. These findings have the potential to revolutionize the development of highly effective strategies that are tailored to individual requirements for the management and treatment of various diseases.

3.
Arch Microbiol ; 205(6): 252, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37249707

RESUMO

Inflammatory bowel disease (IBD) is a chronic recurrent inflammation of the gastrointestinal tract (GIT). IBD patients are susceptible to various infections such as viral infections due to the long-term consumption of immunosuppressive drugs and biologics. The antiviral and IBD protective traits of flavonoids have not been entirely investigated. This study objective included an overview of the protective role of flavonoids quercetin and silymarin in viral-associated IBD. Several viral agents such as cytomegalovirus (CMV), Epstein-Barr virus (EBV), varicella zoster virus (VZV) and enteric viruses can be reactivated and thus develop or exacerbate the IBD conditions or eventually facilitate the disease remission. Flavonoids such as quercetin and silymarin are non-toxic and safe bioactive compounds with remarkable anti-oxidant, anti-inflammatory and anti-viral effects. Mechanisms of anti-inflammatory and antiviral effects of silymarin and quercetin mainly include immune modulation and inhibition of caspase enzymes, viral binding and replication, RNA synthesis, viral proteases and viral assembly. In the nutraceutical sector, natural flavonoids low bioavailability and solubility necessitate the application of delivery systems to enhance their efficacy. This review study provided an updated understanding of the protective role of quercetin and silymarin against viral-associated IBD.


Assuntos
Infecções por Vírus Epstein-Barr , Doenças Inflamatórias Intestinais , Silimarina , Humanos , Herpesvirus Humano 4/genética , Quercetina/farmacologia , Silimarina/farmacologia , Flavonoides , Doenças Inflamatórias Intestinais/tratamento farmacológico , Antivirais/farmacologia , Antivirais/uso terapêutico
4.
J Int Soc Sports Nutr ; 18(1): 15, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33588872

RESUMO

BACKGROUND: chicken meat extract is a popular functional food in Asia. It is rich in the bioactive compounds carnosine and anserine, two histidine-containing dipeptides (HCD). Studies suggest that acute pre-exercise ingestion of chicken extracts has important applications towards exercise performance and fatigue control, but the evidence is equivocal. This study aimed to evaluate the ergogenic potential of the pre-exercise ingestion of a homemade chicken broth (CB) vs a placebo soup on a short-lasting, high-intensity cycling exercise. METHODS: fourteen men participated in this double-blind, placebo-controlled, crossover intervention study. Subjects ingested either CB, thereby receiving 46.4 mg/kg body weight of HCD, or a placebo soup (similar in taste without HCD) 40 min before an 8 min cycling time trial (TT) was performed. Venous blood samples were collected at arrival (fasted), before exercise and at 5 min recovery. Plasma HCD were measured with UPLC-MS/MS and glutathione (in red blood cells) was measured through HPLC. Capillary blood samples were collected at different timepoints before and after exercise. RESULTS: a significant improvement (p = 0.033; 5.2%) of the 8 min TT mean power was observed after CB supplementation compared to placebo. Post-exercise plasma carnosine (p <  0.05) and anserine (p <  0.001) was significantly increased after CB supplementation and not following placebo. No significant effect of CB supplementation was observed either on blood glutathione levels, nor on capillary blood analysis. CONCLUSIONS: oral CB supplementation improved the 8 min TT performance albeit it did not affect the acid-base balance or oxidative status parameters. Further research should unravel the potential role and mechanisms of HCD, present in CB, in this ergogenic approach.


Assuntos
Anserina/farmacologia , Ciclismo/fisiologia , Carnosina/farmacologia , Carne , Substâncias para Melhoria do Desempenho/farmacologia , Equilíbrio Ácido-Base , Análise de Variância , Animais , Anserina/administração & dosagem , Anserina/sangue , Desempenho Atlético , Capilares , Carnosina/administração & dosagem , Carnosina/sangue , Galinhas , Cromatografia Líquida , Estudos Cross-Over , Método Duplo-Cego , Alimentos , Glutationa/sangue , Humanos , Masculino , Substâncias para Melhoria do Desempenho/administração & dosagem , Substâncias para Melhoria do Desempenho/sangue , Placebos/administração & dosagem , Espectrometria de Massas em Tandem , Fatores de Tempo
5.
Eur J Sport Sci ; 21(1): 61-68, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31944160

RESUMO

In this study, we aimed to determine the exercise intensities eliciting the highest (FATmax) and the lowest (FATmin) fat oxidation rate in male cyclists and to compare these intensities with their individual aerobic (AeT) and anaerobic (AnT) thresholds, respectively. Twenty-two moderately trained male cyclists performed a 2-min stage graded exercise test until exhaustion using breath-by-breath gas analysis to determine maximal oxygen consumption (VO2max). The fat oxidation rate was calculated using a stoichiometric equation, with metabolic thresholds being determined by ventilatory gas analysis. In the present group of subjects, FATmax was found at a 21.34 ± 3.64 ml·kg-1·min-1 corresponding to 45.05 ± 7.68% VO2max. AeT occurred at an exercise intensity of 22.15 ± 4.84 ml·kg-1·min-1, matching 46.76 ± 10.24% VO2max. AnT and FATmin were located at intensities equivalent to 32.56 ± 5.52 ml·kg-1·min-1 and 32.30 ± 5.35 ml·kg-1·min-1 which corresponded to 68.74 ± 11.65 and 68.19 ± 11.29% VO2max, respectively. The correlation between FATmax and AeT was strong (r = 0.80, p < 0.05). No statistical difference was observed between FATmin and AnT (r = 0.99, p < 0.05). The strong relationship between observed indices can be used to provide a more tailored exercise approach.


Assuntos
Ciclismo/fisiologia , Exercício Físico/fisiologia , Metabolismo dos Lipídeos/fisiologia , Consumo de Oxigênio/fisiologia , Resistência Física/fisiologia , Adulto , Limiar Anaeróbio/fisiologia , Desempenho Atlético/fisiologia , Teste de Esforço , Humanos , Masculino , Oxirredução
6.
J Sci Food Agric ; 99(13): 5680-5686, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31150113

RESUMO

BACKGROUND: Poultry meat has high levels of histidine-containing dipeptides (HCD) and consumption of meat rich in HCD may elicit certain health benefits. The aim of this work was to compare the HCD content (anserine and carnosine) in the breast and thigh muscles of two broiler strains differing in growth rate, feeding regime, and age at slaughter. A 3 (production system) × 2 (sex) × 2 (age at slaughter) full factorial arrangement was applied with fast-growing Ross 308 chicks fed ad libitum (ROSS-AL), slow-growing Sasso T451 chicks fed ad libitum (SASSO-AL), and Ross 308 chicks given limited feeding (ROSS-LIM). At the age of 40 and 62 days, eight birds per production system × sex combination were randomly selected for sampling of the breast and thigh muscle. Muscle HCD content was determined by high-performance liquid chromatography (HPLC). RESULTS: Across treatments, levels of anserine were 2.5- and 1.9-fold higher than carnosine in breast and thigh muscle respectively (P < 0.001), and levels of anserine and carnosine were 2.2- and 2.8-fold higher respectively in breast versus thigh muscle (P < 0.001). In breast muscle, SASSO-AL had higher levels of HCD than ROSS-AL and ROSS-LIM (P < 0.001). Considering different market meat types, breast muscle of 62-day-old SASSO-AL birds had more than threefold higher content of HCD compared to thigh muscle of 40-day-old ROSS-AL birds (P < 0.001). CONCLUSION: Large differences in muscle HCD content were found, varying according to type of muscle and broiler. © 2019 Society of Chemical Industry.


Assuntos
Anserina/análise , Carnosina/análise , Galinhas/metabolismo , Histidina/metabolismo , Músculo Esquelético/química , Ração Animal/análise , Animais , Anserina/metabolismo , Carnosina/metabolismo , Galinhas/crescimento & desenvolvimento , Feminino , Masculino , Carne/análise , Músculo Esquelético/metabolismo
7.
Amino Acids ; 51(1): 103-114, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30302566

RESUMO

Carnosine (beta-alanyl-L-histidine) and its methylated analogue anserine are present in relevant concentrations in the omnivore human diet. Several studies reported promising therapeutic potential for carnosine in various rodent models of oxidative stress and inflammation-related chronic diseases. Nevertheless, the poor serum stability of carnosine in humans makes the translation of rodent models hard. Even though anserine and carnosine have similar biochemical properties, anserine has better serum stability. Despite this interesting profile, the research on anserine is scarce. The aim of this study was to explore the bioavailability and stability of synthesized anserine by (1) performing in vitro stability experiments in human plasma and molecular modelling studies and by (2) evaluating the plasma and urinary pharmacokinetic profile in healthy volunteers following different doses of anserine (4-10-20 mg/kg body weight). A bio-analytical method for measuring anserine levels was developed and validated using liquid chromatography-electrospray mass spectrometry. Both plasma (CMAX: 0.54-1.10-3.12 µM) and urinary (CMAX: 0.09-0.41-0.72 mg/mg creatinine) anserine increased dose-dependently following ingestion of 4-10-20 anserine mg/kg BW, respectively. The inter-individual variation in plasma anserine was mainly explained by the activity (R2 = 0.75) and content (R2 = 0.77) of the enzyme serum carnosinase-1. Compared to carnosine, a lower interaction energy of anserine with carnosinase-1 was suggested by molecular modelling studies. Conversely, the two dipeptides seems to have similar interaction with the PEPT1 transporter. It can be concluded that nutritionally relevant doses of synthesized anserine are well-absorbed and that its degradation by serum carnosinase-1 is less pronounced compared to carnosine. This makes anserine a good candidate as a more stable carnosine-analogue to attenuate chronic diseases in humans.


Assuntos
Anserina/análise , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Adulto , Anserina/sangue , Anserina/farmacocinética , Anserina/urina , Carnosina/metabolismo , Feminino , Voluntários Saudáveis , Humanos , Masculino
8.
J Physiol ; 594(17): 4849-63, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27062388

RESUMO

KEY POINTS: Using recombinant DNA technology, the present study provides the first strong and direct evidence indicating that ß-alanine is an efficient substrate for the mammalian transaminating enzymes 4-aminobutyrate-2-oxoglutarate transaminase and alanine-glyoxylate transaminase. The concentration of carnosine and anserine in murine skeletal and heart muscle depends on circulating availability of ß-alanine, which is in turn controlled by degradation of ß-alanine in liver and kidney. Chronic oral ß-alanine supplementation is a popular ergogenic strategy in sports because it can increase the intracellular carnosine concentration and subsequently improve the performance of high-intensity exercises. The present study can partly explain why the ß-alanine supplementation protocol is so inefficient, by demonstrating that exogenous ß-alanine can be effectively routed toward oxidation. ABSTRACT: The metabolic fate of orally ingested ß-alanine is largely unknown. Chronic ß-alanine supplementation is becoming increasingly popular for improving high-intensity exercise performance because it is the rate-limiting precursor of the dipeptide carnosine (ß-alanyl-l-histidine) in muscle. However, only a small fraction (3-6%) of the ingested ß-alanine is used for carnosine synthesis. Thus, the present study aimed to investigate the putative contribution of two ß-alanine transamination enzymes, namely 4-aminobutyrate-2-oxoglutarate transaminase (GABA-T) and alanine-glyoxylate transaminase (AGXT2), to the homeostasis of carnosine and its methylated analogue anserine. We found that, when transfected into HEK293T cells, recombinant mouse and human GABA-T and AGXT2 are able to transaminate ß-alanine efficiently. The reaction catalysed by GABA-T is inhibited by vigabatrin, whereas both GABA-T and AGXT2 activity is inhibited by aminooxyacetic acid (AOA). Both GABA-T and AGXT2 are highly expressed in the mouse liver and kidney and the administration of the inhibitors effectively reduced their enzyme activity in liver (GABA-T for vigabatrin; GABA-T and AGXT2 for AOA). In vivo, injection of AOA in C57BL/6 mice placed on ß-alanine (0.1% w/v in drinking water) for 2 weeks lead to a 3-fold increase in circulating ß-alanine levels and to significantly higher levels of carnosine and anserine in skeletal muscle and heart. By contrast, specific inhibition of GABA-T by vigabatrin did not affect carnosine and anserine levels in either tissue. Collectively, these data demonstrate that homeostasis of carnosine and anserine in mammalian skeletal muscle and heart is controlled by circulating ß-alanine levels, which are suppressed by hepatic and renal ß-alanine transamination upon oral ß-alanine intake.


Assuntos
Anserina/metabolismo , Carnosina/metabolismo , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , Transaminases/metabolismo , beta-Alanina/metabolismo , Ácido Amino-Oxiacético/farmacologia , Animais , Encéfalo/metabolismo , Inibidores Enzimáticos/farmacologia , GABAérgicos/farmacologia , Células HEK293 , Homeostase , Humanos , Rim/metabolismo , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , RNA Mensageiro/metabolismo , Transaminases/antagonistas & inibidores , Transaminases/genética , Vigabatrina/farmacologia , beta-Alanina/sangue , beta-Alanina/urina
9.
Obesity (Silver Spring) ; 24(5): 1027-34, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27040154

RESUMO

OBJECTIVE: Carnosine is a naturally present dipeptide in humans and an over-the counter food additive. Evidence from animal studies supports the role for carnosine in the prevention and treatment of diabetes and cardiovascular disease, yet there is limited human data. This study investigated whether carnosine supplementation in individuals with overweight or obesity improves diabetes and cardiovascular risk factors. METHODS: In a double-blind randomized pilot trial in nondiabetic individuals with overweight and obesity (age 43 ± 8 years; body mass index 31 ± 4 kg/m(2) ), 15 individuals were randomly assigned to 2 g carnosine daily and 15 individuals to placebo for 12 weeks. Insulin sensitivity and secretion, glucose tolerance (oral glucose tolerance test), blood pressure, plasma lipid profile, skeletal muscle ((1) H-MRS), and urinary carnosine levels were measured. RESULTS: Carnosine concentrations increased in urine after supplementation (P < 0.05). An increase in fasting insulin and insulin resistance was hampered in individuals receiving carnosine compared to placebo, and this remained significant after adjustment for age, sex, and change in body weight (P = 0.02, P = 0.04, respectively). Two-hour glucose and insulin were both lower after carnosine supplementation compared to placebo in individuals with impaired glucose tolerance (P < 0.05). CONCLUSIONS: These pilot intervention data suggest that carnosine supplementation may be an effective strategy for prevention of type 2 diabetes.


Assuntos
Carnosina/administração & dosagem , Glucose/metabolismo , Adulto , Glicemia/análise , Peso Corporal , Diabetes Mellitus Tipo 2/sangue , Suplementos Nutricionais , Método Duplo-Cego , Jejum , Feminino , Intolerância à Glucose , Teste de Tolerância a Glucose , Humanos , Insulina/sangue , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Sobrepeso/sangue , Projetos Piloto , Placebos , Fatores de Risco
10.
J Gen Virol ; 91(Pt 2): 521-30, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19812262

RESUMO

Human papillomavirus type 16 (HPV-16) is the cause of cervical cancer. The HPV genome encodes three transforming proteins, E5, E6 and E7. E6 and E7 are the main transforming proteins of HPV, while the role of E5 is still poorly understood. Using three dimensional organotypic raft cultures we show that HaCaT human keratinocytes expressing HPV-16 E5 form a very perturbed epithelium, with simultaneous hyperkeratinization of some cells and defective differentiation of other cells. The basal layer is disturbed and many cells invade the collagen matrix. Many cells among the differentiated layers show characteristics of basal cells: progression through the cell cycle, expression of cytokeratin 14, lack of cytokeratin 1 and production of matrix metalloproteases (MMP). Using deletion mutants which encompass the three hydrophobic domains of E5, we have assigned the ability to promote invasion of the matrix to the first hydrophobic domain, and the capacity to induce MMP9 to the C-terminal four amino acids. We also show that invasion and production of MMP9 can be dissociated, as mutants that are still capable of invasion do not produce MMP9 and vice versa.


Assuntos
Células Epiteliais/virologia , Papillomavirus Humano 16/genética , Proteínas Oncogênicas Virais/química , Proteínas Oncogênicas Virais/metabolismo , Infecções por Papillomavirus/virologia , Deleção de Sequência , Diferenciação Celular , Membrana Celular/metabolismo , Membrana Celular/virologia , Transformação Celular Viral , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Papillomavirus Humano 16/química , Papillomavirus Humano 16/metabolismo , Humanos , Queratina-14/metabolismo , Queratinócitos/citologia , Queratinócitos/metabolismo , Queratinócitos/virologia , Metaloproteinase 9 da Matriz/metabolismo , Proteínas Oncogênicas Virais/genética , Infecções por Papillomavirus/metabolismo , Estrutura Terciária de Proteína
11.
Naturwissenschaften ; 91(7): 342-5, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15257390

RESUMO

The burrowing activity of the invasive red-swamp crayfish, Procambarus clarkii, was studied along a 25-m-long transect in an irrigation ditch system in Italy. Our objective was to understand the factors inducing this species' intense digging, which can result in bank collapse and consequently in severe damage to both agricultural fields and natural ecosystems. Burrow morphology and position, together with their occupancy by crayfish and digging, were recorded once every 6 h for 10 consecutive days. The majority of burrows were simple, although a few had a chimney and were constructed at a farther distance from the water surface than simple burrows. Burrow occupancy and digging, together with their plugged/unplugged status, were constant throughout a 24-h cycle and were not related to any abiotic parameter of the habitat. Crayfish occupied and dug a burrow for a relatively short time (6 h on average). Once abandoned, old burrows were rarely reoccupied and often collapsed, while crayfish excavated new ones. As a result, the overall number of burrows increased. This massive use of banks by P. clarkii seems to be related to soil composition and humidity, which favour crayfish digging but also cause the easy collapse of burrows.


Assuntos
Astacoidea/fisiologia , Ecossistema , Meio Ambiente , Análise de Variância , Animais
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