Relationship between IL-8 Circulating Levels and TLR2 Hepatic Expression in Women with Morbid Obesity and Nonalcoholic Steatohepatitis

Figure 1. Pro- and anti-inflammatory cytokines involved in the physiopathology of NAFLD progression. IL-1β promotes fat accumulation in hepatocytes and then, it induces liver inflammation and stimulates liver fibrosis in a late stage of the disease [21,31]; TGF-β performs the same function [29]. TNF-α mediates the early stage of NAFLD by fat accumulation in hepatocytes and also facilitates disease progression to a more advanced stage. IL-8 and MCP-1 activate monocytes and macrophages and attract polymorphonuclear leukocytes to the site of inflammation inducing a proinflammatory microenvironment [22,32]. IL-6 induces insulin resistance in hepatocytes [23]. IL-13 appears to activate distinct profibrotic mechanisms during the progression of NAFLD [24]. PAI-1 is a primary regulator of the fibrinolytic system in NASH [25]. A more accentuated proinflammatory stage in NASH patients is indicated by a decrease of the IL-10/IL-17 ratio [26]. IL-7 is known to suppress expression of several molecules known to promote fibrosis and stimulates the expression of factors that protect against it [27]. Adiponectin regulates hepatic insulin resistance and is related to hepatic fat content [22,33]. IL-22 has a…

Figure 2. Circulating levels of IL-8 in women with morbid obesity with normal liver and with nonalcoholic fatty liver disease (A), and women with morbid obesity according to liver damage (B). NAFLD, women with morbid obesity (MO) with nonalcoholic fatty liver disease; NL, women with MO with normal liver; SS, women with MO with simple steatosis; NASH, women with MO with steatohepatitis. p < 0.05 is considered statistically significant.

Figure 3. Circulating levels of IL-8 and adiponectin in women with MO according to the presence or absence of lobular inflammation (A,C) and hepatocellular ballooning (B,D). Data are expressed as medians (10–90th). p < 0.05 is considered statistically significant.

Figure 4. Receiver operating characteristic (ROC) curves for NASH diagnosis. (A) ROC curve for the association between plasma IL-8 levels (pg/mL) and NASH diagnosis in MO patients. (B) ROC curve for the association between plasma adiponectin levels (ng/mL) and no NASH diagnosis in MO patients. The dashed line is a reference line indicating chance prediction. AUC denotes area under the curve.