Related Experiment Video
Updated: May 10, 2026
A Protocol for Constructing a Rat Wound Model of Type 1 Diabetes
Published on: February 17, 2023
Amelioration in wound healing in diabetic toll-like receptor-4 knockout mice
Mohan R Dasu1, Ishwarlal Jialal
1Department of Dermatology, University of California at Davis, Sacramento, CA 95816, USA.
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.
Insights
Toll-like receptor-4 (TLR4) drives prolonged inflammation in diabetic wounds. Blocking TLR4 signaling may reduce inflammation and improve wound healing in diabetes.
Area of Science:
- Immunology
- Endocrinology
- Wound Healing Research
Background:
- Toll-like receptor-4 (TLR4) is crucial in inflammation and diabetes complications.
- Diabetic wounds exhibit prolonged inflammation, impacting healing.
- The role of TLR4 in diabetic wound inflammation requires further investigation.
Purpose of the Study:
- To investigate the contribution of Toll-like receptor-4 (TLR4) expression and activation to prolonged inflammation in diabetic wounds.
- To assess the impact of TLR4 knockout on inflammation and healing in a mouse model of diabetes.
Main Methods:
- Diabetes was induced in C57BL/6J and TLR4 knockout (KO) mice using streptozotocin (STZ).
- Full-thickness excision wounds were created on diabetic and non-diabetic mice.
- TLR4 mRNA and protein expression, IL-6, TNF-α, and NF-κB activation were analyzed using real-time PCR and Western blot. Wound healing was assessed by measuring wound size.
Main Results:
- TLR4 mRNA and protein expression were significantly increased in diabetic mouse wounds compared to non-diabetic controls.
- Interleukin-6 (IL-6), Tumor Necrosis Factor-alpha (TNF-α) concentrations, and nuclear factor-kappaB (NF-κB) activation were elevated in diabetic wounds.
- Knockout of TLR4 in diabetic mice (TLR4 KO) reduced inflammation and improved wound healing.
Conclusions:
- Increased TLR4 expression and activation contribute significantly to the prolonged inflammation observed in diabetic wounds.
- The absence of TLR4 may lead to decreased inflammation and enhanced wound healing in diabetic conditions.
- Targeting TLR4 presents a potential therapeutic strategy for improving diabetic wound healing.
