1Universitätsmedizin der Johannes Gutenberg-Universität Mainz Labor für Molekulare Kardiologie Mainz, Deutschland; 2Universitätsmedizin der Johannes Gutenberg-Universität Mainz Kardiologie 1, Zentrum für Kardiologie Mainz, Deutschland; 3Universitätsmedizin der Johannes Gutenberg-Universität Mainz Klinik und Poliklinik für Herz-, Thorax- und Gefäßchirurgie Mainz, Deutschland; 4Universitätsmedizin der Johannes Gutenberg-Universität Mainz Zentrum für Kardiologie Mainz, Deutschland; 5Universitätsmedizin der Johannes Gutenberg-Universität Mainz Institut für Kardiologie - Vaskuläre Kardiologie Mainz, Deutschland
Background: Diabetes mellitus is a chronic metabolic disease characterized by hyperglycemia caused by impaired production or response to insulin. This leads to severe cardio- and neurovascular complications. It has been shown that diabetic patients have a two times higher chance of developing cardiovascular disease compared to healthy people. In the last decade, traffic noise has been recognized as an important environmental risk factor. We have previously shown that aircraft noise exposure causes oxidative stress-mediated cardiovascular damage. Despite epidemiological data indicating, that traffic noise increases the risk of metabolic diseases such as diabetes, the interaction of these two risk factors has not yet been investigated. Therefore, we studied the effects of aircraft noise exposure on cardiovascular complications, specifically microvascular dysfunction and perivascular adipose tissue inflammation, in 3 different murine models of diabetes mellitus.
Methods and Results: C57BL/6 mice were treated with streptozotocin (i.p. injections, 50 mg/kg/d for 5 days) to induce type I diabetes and treated with S961 (subcutaneous osmotic minipumps, 0.57 mg/kg/d for 7 days) or fed a high-fat diet (Western Diet, 20 weeks) to induce type II diabetes. To investigate the effects of aircraft noise, we exposed control and diabetic mice to aircraft noise (maximum sound pressure level of 85 dB(A), average sound pressure level of 72 dB(A)) for the last 4 days of the treatment period.
Our data show, that aircraft noise exposure worsens the diabetes-induced microvascular dysfunction of the mesenteric artery and of cerebral arterioles. This was revealed by endothelium-dependent relaxation in response to acetylcholine. There is evidence that adipose tissue inflammation and dysfunction leads to insulin resistance and therefore type II diabetes. We were able to show, that exposure to aircraft noise has additive effects on the perivascular adipose tissue dysfunction present in diabetic animals. Namely, we observed an increase in markers of oxidative stress and inflammation.
Conclusion: We investigated the effects of aircraft noise exposure on diabetes mellitus-associated cardiovascular complications. Our preclinical data indicate that exposure to aircraft noise may have additive effects on perivascular adipose tissue inflammation and microvascular dysfunction. Aircraft noise exposure poses an increased danger to patients at high cardiovascular risk, with pre-existing cardio-metabolic diseases such as diabetes.
Support or Funding Information: Boehringer Ingelheim Stiftung (BIS) - Research Consortium „Novel and neglected risk factors“, continuous funding by the Deutsches Zentrum für Herz-Kreislauf-Forschung (DZHK).