title: Amelioration in wound healing in diabetic toll-like receptor-4 knockout mice.
abstract: Toll-like receptor-4 (TLR4) is a sentinel pathogen recognition receptor with a pivotal role in inflammation, tissue injury, diabetes and its complications. The aim of the study was to examine the contribution of TLR4 expression and activation to the prolonged inflammation observed in diabetic wounds. Diabetes was induced in male C57BL/6J and TLR4 knockout (KO) mice using streptozotocin (STZ) with matching non-diabetic mice as control. After 2weeks of persistent hyperglycemia in the mice, full-thickness excision wounds were made on the backs aseptically. Total RNA and protein were subjected to real-time PCR and western blot analyses. Wound sizes were measured using digital planimetry. TLR4 mRNA and protein expression increased significantly in wounds of diabetic mice compared with non-diabetic mice (P<0.05). IL-6, TNF-α concentration and nuclear factor-κB (NF-κB) activation were increased in diabetic wounds compared to non-diabetic wounds and knockout of TLR4 alleviates wound healing and decreases inflammation in diabetic TLR4 KO mice. Collectively, our findings show that increased TLR4 mRNA and protein expression and activation contribute to the prolonged inflammation in the diabetic wounds and that absence of TLR4 may result in decreased inflammation and improved wound healing.
authors.affiliation: Department of Dermatology, University of California at Davis, Sacramento, CA 95816, USA. Electronic address: ravi.dasu@ucdmc.ucdavis.edu.
authors.forename: Mohan R
authors.initials: MR
authors.lastname: Dasu
authors.forename: Ishwarlal
authors.initials: I
authors.lastname: Jialal
mesh_terms: D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000139:chemically induced / Q000235:genetics* / Q000503:physiopathology; D007249:Inflammation / Q000235:genetics / Q000503:physiopathology; D051218:Lymphocyte Antigen 96 / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D013311:Streptozocin; D051197:Toll-Like Receptor 4 / Q000235:genetics* / Q000378:metabolism; D014945:Wound Healing / Q000235:genetics*
chemical_list: C411728:Ly96 protein, mouse; D051218:Lymphocyte Antigen 96; C493487:Tlr4 protein, mouse; D051197:Toll-Like Receptor 4; D013311:Streptozocin
keywords: Diabetes Mellitus; Inflammation; TLR4; Wound healing