RESUMO
Mucositis is an inflammation of the gastrointestinal mucosa resulting from high doses of radio/chemotherapy treatment and may lead to interruption of antineoplasic therapy. Soluble fibres, like pectin, increase SCFA production, which play a role in gut homoeostasis and inflammation suppression. Due to the properties of pectin, the aim of the present study was to evaluate the effect of a high-fibre (HF) diet on chemotherapy-induced mucositis in a murine model. C57/BL6 mice received control (AIN93M), HF, low/zero fibre (LF) diets for 10 d prior to mucositis challenging with irinotecan (75 mg/kg), or they were treated with acetate added to drinking water 5 d prior to and during the mucositis induction. Mice that received the HF diet showed decreased immune cells influx and improved histopathological parameters in the intestine, compared with mice that received the normal diet. Furthermore, the HF diet decreased intestinal permeability induced in the mucositis model when compared with the control group. This effect was not observed for acetate alone, which did not improve gut permeability. For instance, mice that received the LF diet had worsened gut permeability, compared with mice that received the normal diet and mucositis. The effects of the HF and LF diets were shown to modulate the intestinal microbiota, in which the LF diet increased the levels of Enterobacteriaceae, a group associated with gut inflammation, whereas the HF diet decreased this group and increased Lactobacillus and Bifidobacterium (SCFA producers) levels. In conclusion, the results demonstrated the importance of dietary fibre intake in the modulation of gut microbiota composition and homoeostasis maintenance during mucositis in this model.
Assuntos
Antineoplásicos , Fibras na Dieta/administração & dosagem , Mucosite , Animais , Antineoplásicos/efeitos adversos , Modelos Animais de Doenças , Inflamação , Camundongos , Mucosite/induzido quimicamente , PectinasRESUMO
The use of probiotics to prevent or treat mucosal inflammation has been studied; however, the combined effect of probiotics and prebiotics is unclear. The aim of this study was to test whether oral administration of a synbiotic (Simbioflora®) preparation containing Lactobacillus paracasei, Lactobacillus rhamnosus, Lactobacillus acidophilus and Bifidobacterium lactis plus fructooligosaccharide could help control mucosal inflammation in experimental mucositis induced by 5-fluorouracil (5-FU). Male BALB/c mice were randomly divided into six groups: control (CTL), control + prebiotic (CTL+P), control + synbiotic (CTL+S), mucositis (MUC), mucositis + prebiotic (MUC+P), and mucositis + synbiotic (MUC+S). Mice from the CTL+S, MUC+S, CTL+P, and MUC+P groups received synbiotic or prebiotic daily by oral gavage for 13 days. Mice in the CTL and MUC groups received the same volume of saline. On day 11, mice in the MUC, MUC+P, and MUC+S groups received an intraperitoneal injection of 300 mg/kg 5-FU to induce mucositis. After 72 h, all mice were euthanised. Intestinal permeability, intestinal histology, and biochemical parameters were analysed. Group MUC showed a greater weight loss and increased intestinal permeability (0.020 counts per min [cpm]/g) compared to the CTL group (0.01 cpm/g) P<0.05. Both treatments attenuated weight loss compared to the MUC group. Nonetheless, the synbiotic caused a greater reduction in intestinal permeability (0.012 cpm/g) compared to the MUC (0.020 cpm/g) and MUC+P (0.016 cpm/g) groups P<0.05. Mice in groups MUC+P and MUC+S displayed significant recovery of lesions and maintenance of the mucus layer. There were no differences in the short-chain fatty acid concentrations in the faeces between the MUC and CTL groups (P>0.05). Increased acetate and propionate concentrations were evidenced in the faeces of the MUC+P and MUC+S groups. Only the synbiotic treatment increased the butyrate concentration (P<0.05). The results indicate that administration of synbiotic can decrease mucosal damage caused by mucositis.
Assuntos
Mucosite/prevenção & controle , Simbióticos/administração & dosagem , Administração Oral , Animais , Bifidobacterium animalis/crescimento & desenvolvimento , Bifidobacterium animalis/metabolismo , Peso Corporal , Ácidos Graxos Voláteis/análise , Fezes/química , Fluoruracila/administração & dosagem , Fluoruracila/toxicidade , Trato Gastrointestinal/patologia , Lactobacillus/crescimento & desenvolvimento , Lactobacillus/metabolismo , Camundongos Endogâmicos BALB C , Mucosite/induzido quimicamente , Oligossacarídeos/administração & dosagem , Oligossacarídeos/metabolismo , Resultado do TratamentoRESUMO
A malária é uma das doenças transmissíveis de maior importância para a saúde pública brasileira, apesar do ciclo de transmissão e das formas de prevenção e tratamento serem conhecidas há muito tempo. Mesmo sendo uma doença presente no Brasil desde o início da colonização, a malária foi pouco estudade no que diz respeito aos seus aspectos históricos. Esse artigo visa fornecer um panorama do comportamento da doença no Brasil e, em especial, no Estado de São Paulo. A pesquisa baseou-se em obras de história da saúde pública no Brasil e história das epidemias no Brasil e no mundo, além da documentação legislativa para o Estado de São Paulo. Até 1930, a malária grassou no Brasil sem que houvesse uma preocupação das autoridades sanitárias em desenvolver campanhas específicas para o combate à doença. Isto se explica por se tratar de uma doença que, frente a outras que também se apresentavam de forma endêmica ou epidêmica - como a varíola e a febre amarela - não representava uma grande ameaça por ser menor a sua taxa de mortalidade. Com o avanço no controle da malária, chegou-se a acreditar na sua erradicação, mas as mudanças sociais e econômicas que se acentuaram a partir da década de 1970 levaram sua incidência anual a aumentar mais de 10 vezes.