Five Different Noise Intensities Robustly Affects Corticosterone, Gastrin and Endothelin-1 Responses and Initiated Gastric Tissue Damage in Wistar Rats

Likewise other stress response noise stress is also affects the homeostasis of the biological systems and produce stress response in the form of Corticosterone to prevent the damage but if the exposure is longer with higher magnitude it may disrupt the robust ability of the homeostasis and could produce the damage to the biological systems. The goal of our study was to see how five different noise intensities affected stomach tissue damage. 42 healthy rats were divided into five different stress exposure group, normal control (NC) and sham control (SC) groups. Noise stress exposure was delivered for 1 hour per day continued for 30 days in all five noise exposed groups by specially designed noise chamber whereas sham control group of animals kept in noise chamber for 1 hour per day continued for 30 days without noise stress exposure and control group of animals neither exposed to noise stress of any intensities and nor kept in noise chamber without noise but remain in the same experimental room in their homecage for 30 days respectively. Results of the study showed that animals exposed to 60 and 80 dB noise give habituated and not significant Corticosterone, Gastrin and Endothelin-1 responses compared to NC and SC groups while animals exposed to 100, 120 and 140 dB had significantly higher Corticosterone, Gastrin and Endothelin-1 response and also chronic gastric damage was observed compared to later two noise exposed groups respectively. Study concluded that not only higher but also lower noise intensities also initiated the gastric damage even after the adaptation.

Polissacarídeos naturais como abordagem terapêutica experimental no trato gastrointestinal: uma revisão sistemática

O objetivo desse trabalho foi realizar uma análise sistemática da literatura acerca dos principais efeitos dos polissacarideos naturais extraídos de plantas e algas em modelos experimentais de distúrbios gastrointestinais (DGI). Esta revisão se concentra em avanços recentes em estudos experimentais com polissacarídeos naturais no tratamento de doença de refluxo gastroesofágico (DRGE), gastrite, colite e diarreia. Trata-se de uma pesquisa bibliográfica, com abordagem qualitativa, tendo em vista os procedimentos de análise e interpretação dos dados obtidos, realizada através de buscas nas bases de dados: Medical Literature Analysis and Retrievel System Online (Medline), Scientific Electronic Library Online (Scielo) e Biblioteca Nacional de Medicina dos Estados Unidos (PubMed), utilizando os descritores: gum, sulfated polysaccharide, polysaccharide, gastric damage, antidiarrheal, gastroesophageal reflux e colitis em diferentes combinações utilizando o operador booleano “and”. Os artigos incluídos no estudo foram somente os que estavam inclusos nas plataformas, sendo considerados artigos, teses e dissertações, incluídos e indexados no período entre 2011 e 2021, que tivessem como metodologia principal estudos experimentais, pré-clínicos em espectro de atividades in vitro e in vivo sobre os efeitos dos polissacarídeos naturais em modelos de distúrbios gastrointestinais. Os demais artigos que não se enquadravam nesses critérios foram excluídos, chegando a amostra final de 35 trabalhos. Os mecanismos e a efetividade dos polissacarídeos são apresentados e discutidos em detalhes. Em geral, por apresentarem propriedades anti-inflamatória, antioxidante, gastroprotetora e antidiarreica, com boa eficácia e segurança, os estudos sugerem que os polissacarídeos naturais são uma alternativa interessante para o desenvolvimento de terapias inovadoras para DGI.

The Protective Effect of Dapsone Against Ethanol, Stress, and Indomethacin-Induced Gastric Erosion in Rats

Several factors contribute to the development of gastric erosions, including corticosteroids and nonsteroidal anti-inflammatory drugs (NSAIDs), alcohol, and stress. These factors can cause or worsen gastrointestinal ulcers by activating inflammatory pathways or by altering gastric mucosal blood flow. Dapsone is an antimicrobial compound with anti-inflammatory properties. The aim of this study was to evaluate the protective effects of dapsone against gastric erosions induced by alcohol, stress, or indomethacin. Gastric damage was induced in male rats in three different experimental models: ethanol (5 ml/kg, p.o.)-, water-immersion stress-, and indomethacin (30 mg/kg, p.o.)- induced ulcer. Rats in each of these three experimental models were divided into five groups: Normal group, 2. Control group (gastric damage+vehicle), 3. Gastric damage+dapsone 1 mg/kg, 4. Gastric damage+dapsone 3 mg/kg, 5. Gastric damage+dapsone 10 mg/kg. In this study, the J- score ulcer index and histopathological assessment were performed. In addition, inflammatory cytokines levels, NF-κB expression, and MPO activity were determined. Dapsone reduced the tissue injuries and erosion area in all three experimental groups compared to the control group. In addition, serum levels of inflammatory cytokines, TNF-alpha, and IL-1β were reduced in the dapsone treatment groups. The expression of NF-κB and tissue concentration of myeloperoxidase (a marker of neutrophil activation) was also reduced in rats given dapsone. To conclude, dapsone exhibits significant protective effects against the development of experimental gastric erosions in rats, and these effects seem to be related to its anti-inflammatory and antioxidant properties.

The Protective Effects of Probiotic Bacteria on Indomethacin-Induced Gastric Ulcer in Rats

Indomethacin is an anti-inflammatory drug that causes ulcers on the gastric mucosa as a result of its use. For this reason, many experimental studies have been performed to search for new agents in order to treat or prevent gastric ulcers. Probiotic bacteria are live microorganisms, and it has been stated by various studies that these bacteria have antioxidant and anti-inflammatory effects. In this study, we investigated the possible protective effect of various types of probiotic bacteria against acute gastric mucosal damage caused by indomethacin. Our research used 40 female Wistar albino rats that were divided into four groups, with 10 in each group: Control group - Physiological saline was administered daily for 10 days. Indo group - Physiological saline was administered daily for 10 days. On day 11, a single 100mg/kg dose of indomethacin was given. Ranitidine + Indo group - A ranitidine dose of 5mg/kg was administered daily for 5 days. On day 11, a single dose of 100mg/kg of indomethacin was given to the same group. Probiotic + Indo group - A dose of 1 ml/kg of oral probiotic bacteria was administered daily for 10 days. On day 11, a single 100mg/kg dose of indomethacin was given to the same group. After application, rats were killed in appropriate conditions, and stomach tissues were obtained. The obtained gastric tissues were used in the biochemical and histopathological analyzes discussed below. As a result, the administration of indomethacin caused gastric damage, stimulating oxidative stress, inflammation, and apoptosis. However, we found that the use of probiotic bacteria reduces oxidative stress (TOC), increases the activity of antioxidant enzymes (TAC), suppresses inflammation (IL-6, IL-1β, Tnf-α, and COX-2) and inhibits apoptosis (Bax and Bcl-2). This suggests that probiotic bacteria inhibit indomethacin-induced apoptosis. Probiotic treatment can mitigate gastric damage and apoptosis caused by indomethacin-induced gastric damage in rats. Probiotic also enhances the restoration of biochemical oxidative enzymes as it has anti-inflammatory, antioxidant and antiapaptotic properties.