Air-polluting diesel exhaust particles, already linked to cardiovascular and respiratory diseases, also can delay diabetic wound healing, according to South Korean researchers.

The team examined the effect of such pollutants on rats, measuring levels of post-exposure inflammation in normal and diabetic fibroblasts, critical collagen-producing cells found in connective tissue.

The pollutants upregulated pro-inflammatory behaviors in three specific cytokines, which had previously been shown to delay wound healing. One of the cytokines, cyclooxygenase-2, is normally undetectable but can be induced with pro-inflammatory stimuli. In this study, exposure to diesel exhaust particles increased cyclooxygenase-2, already implicated in processes related to diabetic neuropathy.

The resulting inflammation can be particularly dangerous for patients with diabetic ulcers.

“Wound healing requires complex cellular and molecular events that can lead to either accelerated or delayed healing, the latter of which can result in chronic wounds,” researchers wrote.

 The full study was published in the March issue of Wounds