RESUMEN
Immunosenescence is marked by a systemic process named inflammaging along with a series of defects in the immunological activity that results in poor responses to infectious agents and to vaccination. Inflammaging, a state of low-grade chronic inflammation, usually leads to chronic inflammatory diseases and frailty in the elderly. However, some elderly escape from frailty and reach advanced age free of the consequences of inflammaging. This process has been called immunological remodeling, and it is the hallmark of healthy aging as described in the studies of centenarians in Italy. The biological markers of healthy aging are still a matter of debate, and the studies on the topic have focused on inflammatory versus remodeling processes and molecules. The sub-clinical inflammatory status associated with aging might be a deleterious event for populations living in countries where chronic infectious diseases are not prevalent. Nevertheless, in other parts of the world where they are, two possibilities may occur. Inflammatory responses may have a protective effect against these infectious agents. At the same time, the long-term consequences of protective immune responses during chronic infections may result in accelerated immunosenescence in these individuals. Therefore, the biological markers of healthy aging can vary according to environmental, cultural, and geographical settings that reflect worldwide, and in a non-biased, non-westernized perspective, the changes that we experience regarding our contacts with microorganisms and the outcomes of such contacts.
Asunto(s)
Envejecimiento/fisiología , Enfermedades Transmisibles/inmunología , Inflamación/inmunología , Microbiota/inmunología , Animales , Enfermedades Transmisibles/epidemiología , Enfermedades Transmisibles/microbiología , Dieta Occidental , Enfermedades Endémicas , Fragilidad , Envejecimiento Saludable , Humanos , Inmunosenescencia , Inflamación/epidemiología , Inflamación/microbiología , Italia/epidemiologíaRESUMEN
BACKGROUND: Arginine has been shown to have several immunological and trophic properties in stressful diseases. Its metabolites, nitric oxide (NO) and polyamines, are related to arginine's effects. Thus, the aim of this study was to determine the effects of the NO donor L-arginine and the role of inducible NO synthase (iNOS) on intestinal permeability and bacterial translocation in a model of intestinal obstruction (IO) induced by a simple knot in the terminal ileum. MATERIAL AND METHODS: Male C57BL6/J wild-type (WT) and iNOS knockout (iNOS-/-) mice were randomized into 6 groups: Sham and Sham-/- (standard chow), IO and IO-/- (standard chow +IO), and Arg and Arg-/- (standard chow supplemented with arginine + IO). After 7 days of treatment with standard or supplemented chows, IO was induced and intestinal permeability and bacterial translocation were evaluated. The small intestine and its contents were harvested for histopathological and morphometric analysis and the determination of polyamine concentration. RESULTS: Pretreatment with arginine maintained intestinal permeability (P > .05; Arg and Arg-/- groups vs Sham and Sham-/- groups), increased polyamine concentration in intestinal content (P < .05; Arg vs IO group), and decreased bacterial translocation in WT animals (Arg group vs IO and IO-/- groups). Absence of iNOS also presented a protective effect on permeability but not on bacterial translocation. CONCLUSION: Arginine supplementation and synthesis of NO by iNOS are important factors in decreasing bacterial translocation. However, when intestinal permeability was considered, NO had a detrimental role.
Asunto(s)
Arginina/administración & dosificación , Traslocación Bacteriana/efectos de los fármacos , Escherichia coli/fisiología , Intestino Delgado/metabolismo , Intestino Delgado/microbiología , Óxido Nítrico Sintasa de Tipo II/genética , Animales , Íleon/efectos de los fármacos , Íleon/metabolismo , Íleon/patología , Obstrucción Intestinal/metabolismo , Obstrucción Intestinal/microbiología , Obstrucción Intestinal/patología , Intestino Delgado/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Permeabilidad , Poliaminas/metabolismoRESUMEN
BACKGROUND: Citrulline has been shown to be an important marker of gut function, regulator of protein metabolism, and precursor of arginine. The authors assessed the effects of citrulline on gut barrier integrity and bacterial translocation (BT) in mice undergoing intestinal obstruction. METHODS: Mice were divided into 3 groups: sham, intestinal obstruction (IO), and citrulline (CIT). The CIT group received a diet containing 0.6% citrulline; the IO and sham groups were fed a standard chow diet. On the eighth day of treatment, all animals received a diethylenetriamine pentaacetic acid (DTPA) solution labeled with (99m)Technetium ((99m)Tc-DTPA) by gavage for the intestinal permeability study. Terminal ileum was ligated except the sham group, which only underwent laparotomy. After 4, 8, and 18 hours, blood was collected to determine radioactivity. Samples of ileum were removed 18 hours after intestinal obstruction for histological analysis. In another set of animals, BT was evaluated. Animals received 10(8) CFU/mL of (99m)Tc-Escherichia coli by gavage; 90 minutes later, they underwent ileum ligation. Intestinal fluid and serum were collected to measure sIgA and cytokines. RESULTS: The CIT group presented decreased intestinal permeability and BT when compared with the IO group (P < .05). Histopathology showed that citrulline preserved the ileum mucosa. The sIgA concentration was higher in the CIT group (P < .05). The IO group presented the highest levels of interferon-γ (P < .05). CONCLUSIONS: Pretreatment with citrulline was able to preserve barrier integrity and also modulated the immune response that might have affected BT decrease.
Asunto(s)
Citrulina/farmacología , Íleon/efectos de los fármacos , Mucosa Intestinal/efectos de los fármacos , Obstrucción Intestinal/tratamiento farmacológico , Animales , Arginina/farmacología , Traslocación Bacteriana/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Íleon/metabolismo , Íleon/microbiología , Inmunoglobulina A Secretora/sangre , Interferón gamma/sangre , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología , Obstrucción Intestinal/microbiología , Masculino , Ratones , Ácido Pentético/administración & dosificación , PermeabilidadRESUMEN
Este estudo teve como objetivos investigar o teor de alfa-caroteno, beta-caroteno e calcular o valor de vitamina A em hortaliças comercializadas no mercado formal e informal de Viçosa, Estado de Minas Gerais, bem como avaliar a influência das quatro estações do ano e do local de comercialização sobre o conteúdo desses nutrientes. As hortaliças (bertalha, cebolinha, coentro, manjericão e salsa) foram analisadas utilizando-se a cromatografia líquida de alta eficiência (CLAE). Devido ao conteúdo inexpressivo de alfa-caroteno em todas as amostras, foi possível quantificar apenas o beta-caroteno. Não se verificou diferença estatisticamente significativa (alfa = 0,05) no conteúdo de beta-caroteno das hortaliças entre os diferentes estabelecimentos, nem entre as estações do ano. As hortaliças mostraram-se excelentes fontes de provitamina A, e se consumidas regularmente, contribuem de forma importante na adequação diária de vitamina A para adultos e crianças. Além disso, esses alimentos são acessíveis à população por apresentarem baixo custo e serem facilmente encontrados.
This study aimed to investigate the level of alpha-carotene, beta-carotene and to calculate the value of vitamin A in vegetables sold at local markets and informal markets of Viçosa, Minas Gerais State, as well as to evaluate the seasonal and commercial effects on the content of these pigments. The vegetables (basella, green onion, cilantro, sweet basil and parsley) were analyzed through high-performance liquid chromatography (HPLC), being alpha-carotene the only pigment present in all the analyzed samples. No significant statistical differences (beta = 0.05) were found in the contents of beta-carotene of the vegetables either among the different stores, or among the different seasons. The vegetables analyzed are great provitamin A sources and, if eaten on a regular basis, they can fit the daily requirements of vitamin A for adults and children. Besides, these foods are very accessible due to their low cost and availability in the market.