**4. Conclusion**

It is very clear that mechanisms responsible for the development of NAFLD, which can occur through a diet, typically western diet, rich in saturated fat and fructose, in addition to other simple sugars, promotes metabolic disorders. This initially affects processes such as liver lipogenesis, resistance to insulin, and even as it is now known, negative consequences due to an unbalanced microbiota, with greater release of LPS. Studies on the mechanisms involved in the development of NAFLD and progression to NASH has steadily increased, due to the increasing number of obesity and liver disorders worldwide. The combination of factors that interfere with etiology such as weight gain, dietary ingredients and genetics are factors that further instigate the urgency to elucidate its effects on the liver using animal models of human diseases.

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