The effects of PM10 on electrocardiogram parameters, blood pressure and oxidative stress in healthy rats: the protective effects of vanillic acid

Particulate matter (PM) inhalation is an established trigger of cardiovascular events such as cardiac arrhythmias that occur within hours to days after exposure. Higher daily PM levels are related to acute increases in systemic arterial blood pressure (BP). The aim of the present study was to evaluate the effects of PM₁₀ on electrocardiogram (ECG) parameters, blood pressure, lipid peroxidation (MDA), xanthine oxidase, and antioxidant enzyme in healthy rats and also to examine the protective effects of vanillic acid (VA) in this respect. Eighty male Wistar rats were divided into eight groups (n = 10), namely control (normal saline, gavage), VAc (10 mg/kg), sham (normal saline, intratracheal instillation), VA (10 mg/kg VA, 10 days gavage +0.1 ml normal saline, intratracheal instillation), PM1 (0.5 mg/kg), PM2 (2.5 mg/kg), PM3 (5 mg/kg), PM3 + VA (5 mg/kg, intratracheal instillation + 10 mg/kg VA, 10 days, gavage) groups. The rats were anesthetized and 0.1 ml of saline as well as a certain concentration of PM₁₀ was instilled into the trachea and it was repeated after 48 h, then 30 min after that, PR interval, QTc, and systolic blood pressure were measured. The activities of antioxidant enzymes, xanthine oxidase (XOX), and malondialdehyde (MDA) were measured in plasma by special Kits. A significant increase in blood pressure (BP), PR interval, QTc, MDA, and XOX and a significant decrease in antioxidant enzyme (CAT, SOD, and GPx) occurred in PM₁₀ groups. Vanillic acid ameliorated blood pressure, QTc, PR interval, XOX, MDA, and increased antioxidant enzymes (SOD, CAT, and GPx) significantly. In the present study, it was shown that PM₁₀ had devastating effects on the heart and blood pressure, probably due to the increased oxidative stress in healthy rats. Vanillic acid could improve the symptoms of PM₁₀ exposure and can be used as an antioxidant agent against the harmful effects of PM₁₀.