## 4 Discussion  
The entry of bacteria or their antigens into the mucosa due to the disruption of the epithelial layer of the intestine is considered the causative event in the prognosis of enterocolitis [33]. As shown previously, intestinal inflammation can be easier or more readily induced in animal models where the factors that damage the epithelial layer are clear. [PERSON] et al., in a landmark study, confirmed that mucosal inflammation could be  
Figure 6: Microscopic damage score. The mice treated with 2.5% DSS gained significantly higher colitis scores than the 1.5% DSS group. Although, the 3.5% DSS-treated mice had an even higher score than the 2.5% and 1.5% DSS-treated mice. N = five mice per group (*** \(p<\) 0.0001 and ** \(p<\) 0.001). Figure 7: Effect of DSS on the expression levels of TNF \(\alpha\) (graph (**A**)) and MPO (graph (**B**)) in colon tissue. N = five mice per group (*** \(p<\) 0.0001 and ** \(p<\) 0.001). prevented with a healthy, intact epithelium, where cadherins perform a very crucial role in their adhesion [34]. As discussed before, several types of animal models have been evaluated to study intestinal inflammation. Proper selection of an animal model that can mimic human disease is crucial for the development of new drugs. Dextran sulfate sodium (DSS) is known to induce colitis in animal models by disrupting the intestinal epithelial barrier and causing an inflammatory response. One consequence of this disruption is alteration in the constitution of the gut microbiota. Experimental studies have shown that DSS treatment leads to a decrease in the diversity of gut microbial communities in mice. Specifically, DSS treatment is associated with a decrease in the relative abundance of beneficial bacteria such as Lactobacillus and Bifidobacterium, while increasing the relative abundance of potentially pathogenic bacteria such as Enterococcus and Proteobacteria [35]. These changes in microbial composition and diversity can contribute to the development and progression of colitis by altering host-microbe interactions and promoting inflammation. However, it is important to note that the effects of DSS on the gut microbiota can vary depending on the DSS concentration used, the duration of treatment, and other experimental factors [36]. In the present work, we examined DSS because of its easy availability, low cost, and short time to induce inflammation in mice. DSS-induced colitis causes a series of events that damage the colon epithelium. These events result in an innate immune response that alters the function of the epithelial barrier. The effect of the different concentrations on the degree of damage to the epithelial barrier was carefully evaluated in this study. We have selected three different concentrations of DSS based on previous studies reported in the literature and studies carried out in our laboratory [23; 27]. The administration of 1.5% DSS \(w/v\) DSS in drinking water causes cryptic structures, cytokine damage, and cryptic abscesses. For a short period of time, 1.5% DSS \(w/v\) of DSS could cause reproducible acute inflammation limited to the colon. With 3.5% DSS \(w/v\) in drinking water, we observed a more damaged cryptic structure, infiltration of cytokines, and cryptic abscesses. DSS-induced colitis inflammation is independent of T-cell-mediated immunity, as demonstrated in immunodeficient mice such as SCID4 and Rag1. This indicates that the cytokines produced by the innate immune cells are sufficient to produce inflammation in colitis [37; 38]. Several studies have confirmed the crucial roles of macrophages and neutrophils in mucosal inflammation [39; 40; 41]. This makes the DSS-induced colitis models more useful for the investigation of the innate immune response. These findings are crucial, which indicates that the cytokines produced by the macrophages are very crucial in regulating the functions of epithelial cells. The DSS models are also found to be very crucial in exploring the molecular events of the innate immune system in colitis, especially those of TLR [42; 43].