Improvement in insulin sensitivity and prevention of high fat diet-induced liver pathology using a CXCR2 antagonist

Abstract

Background Liver pathology (LP) characteristic of non-alcoholic fatty acid disease (NAFLD)/non-alcoholic steatohepatitis (NASH) is a prevalent co-morbidity of type 2 diabetes (T2D). Accumulating evidence indicates that neutrophils driving insulin resistance (IR), including hepatic IR, precipitate T2D-associated NAFLD/NASH. We hypothesized that targeting neutrophil accumulation into insulin-sensitive tissues in mice using a CXCR2 antagonist under T2D-precipitating high fat diet (HFD) could improve insulin sensitivity and prevent the progression towards liver pathology reminiscent of NAFLD/NASH. Methods Mice were age-matched and on standard rodent chow prior to 1:1 randomization into control and HFD formulated with the CXCR2 antagonist AZD5069 or with biologically inactive substitute. They were monitored for metabolic changes including insulin sensitivity using the hyperinsulinemic-euglycemic clamp and hepatic histopathologic evaluation in H&E-stained sections as well as via immunofluorescence microscopy of liver sections for leukocyte markers, collagen 1A1 formation, α-smooth muscle actin (SMA), and galectin-3 expression, for 16 weeks. Statistical tests used to determine significant differences among study groups and outcomes include Student’s t-test, one-way ANOVA, repeated measures two-way ANOVA, and Fisher’s exact test, depending on the analytical question. Results Compared to mice on HFD, mice in the AZD5069-formulated HFD exhibited improved insulin sensitivity, a modest reduction in weight gain, and a significant improvement in LP and markers related to NAFLD/NASH. Mice in the AZD5069-formulated HFD also exhibited reduced neutrophil accumulation into the liver at the end of the 16 week study period. Conclusions These results show, for the first time, the effectiveness of a selective CXCR2 antagonist to improve insulin sensitivity, concomitantly preventing the progression towards LP characteristic of NAFLD/NASH. This represents a novel approach to target IR and developing LP under T2D-susceptible conditions using a single agent. Furthermore, our data extend the growing evidence in support of neutrophils as a leukocyte population that imprints and maintains a chronic inflammatory state in the progression of dysregulated metabolism in liver-specific co-morbid conditions.

Single-cell immune profiling of mouse liver aging reveals Cxcl2 + macrophages recruit neutrophils to aggravate liver injury

“…The recruitment of neutrophils and the formation of NETs led to an impairment in liver repair in aged mice. Previous studies have reported that CXCR2 antagonists (eg, SB225002 and AZD5069) reduce neutrophil infiltration in the liver 42–44 . Based on our findings, targeting CXCL2 led to reduced recruitment of neutrophils by intrahepatic macrophages in aged mice.…”

“…Previous studies have reported that CXCR2 antagonists (eg, SB225002 and AZD5069) reduce neutrophil infiltration in the liver. [42][43][44] Based on our findings, targeting CXCL2 led to reduced recruitment of neutrophils by intrahepatic macrophages in aged mice. Using an HIRI model, we confirmed that an anti-CXCL2 antibody effectively reduced neutrophil recruitment and NET formation, thereby significantly alleviating HIRI in the aged liver.…”

Fluoride Exposure Suppresses Proliferation and Enhances Endoplasmic Reticulum Stress and Apoptosis Pathways in Hepatocytes by Downregulating Sirtuin-1

“…Based on the research reported [ 25 ], at the end of the experiment, all rats were decollated to death, and liver tissues were taken. The liver tissues were fixed in 4% neutral formaldehyde for 48 h, dehydrated in ethanol gradient, and embedded in paraffin wax to produce pathological sections of 3 μ m thickness.…”

Emerging novel targets for nonalcoholic fatty liver disease treatment: Evidence from recent basic studies

“…AZD5069 is a small-molecule inhibitor of CXCR2. AZD5069 can significantly improve liver pathology in NAFLD, with reduced lipid content and hepatic neutrophil accumulation and improved insulin sensitivity[ 65 ]. In addition, AZD5069-mediated CXCR2 inhibition induces reprogramming of the tumor immune microenvironment, which promotes immune checkpoint inhibition in NASH-HCC[ 63 ], suggesting that blocking infiltrating neutrophil CXCR2 can restore sensitivity to immunotherapy in the NASH liver[ 66 ].…”