Induction of CYP1A1, CYP1A2, CYP1B1, increased oxidative stress and inflammation in the lung and liver tissues of rats exposed to incense smoke.

Incense smoke is increasingly being recognized as a potential environmental contaminant and is linked to malignant and non-malignant respiratory diseases. The detoxification of environmental contaminants including polycyclic aromatic hydrocarbons (PAHs) involves the induction of cytochrome P-450 family enzymes (CYPs) by PAHs. However, the detoxification of PAHs also results in the generation of reactive and unstable intermediary metabolites which are implicated in the oxidative stress, DNA damage, and inflammation. It is unclear whether CYPs are similarly induced by incense smoke, which incidentally contains substantial amounts of PAHs. Here, we examined the impact of long-term incense smoke exposure on the induction of CYPs in male Wister Albino rats. Incense smoke exposure significantly induced the expression of CYP1A1, CYP1A2, and CYP1B1 mRNAs in both lung and liver tissues. The extent of CYP1A1 and CYP1B1 induction was significantly higher in the liver compared to that in the lung, while that of CYP1A2 was greater in the lung than in liver. Incense smoke exposure also increased malondialdehyde and reduced glutathione levels in lung and liver tissues, and the catalase activity in the liver tissues to significant levels. Furthermore incense smoke exposure led to a marked increase in TNF-α and IL-4 levels. The data demonstrate for the first time the capacity of incense smoke to induce CYP1 family enzymes in the target and non-target tissues. Induction of CYPs increased oxidative stress and inflammation appear to be intimately linked to promote the carcinogenesis and health complications in people chronically exposed to incense smoke.

Ultrastructural changes, increased oxidative stress, inflammation, and altered cardiac hypertrophic gene expressions in heart tissues of rats exposed to incense smoke.

Incense smoke exposure has recently been linked to cardiovascular disease risk, heart rate variability, and endothelial dysfunction. To test the possible underlying mechanisms, oxidative stress, and inflammatory markers, gene expressions of cardiac hypertrophic and xenobiotic-metabolizing enzymes and ultrastructural changes were measured, respectively, using standard, ELISA-based, real-time PCR, and transmission electron microscope procedures in heart tissues of Wistar rats after chronically exposing to Arabian incense. Malondialdehyde, tumor necrosis alpha (TNF)-α, and IL-4 levels were significantly increased, while catalase and glutathione levels were significantly declined in incense smoke-exposed rats. Incense smoke exposure also resulted in a significant increase in atrial natriuretic peptide, brain natriuretic peptide, ß-myosin heavy chain, CYP1A1 and CYP1A2 messenger RNAs (mRNAs). Rats exposed to incense smoke displayed marked ultrastructural changes in heart muscle with distinct cardiac hypertrophy, which correlated with the augmented hypertrophic gene expression as well as markers of cardiac damage including creatine kinase-myocardial bound (CK-MB) and lactate dehydrogenase (LDH). Increased oxidative stress, inflammation, altered cardiac hypertrophic gene expression, tissue damage, and architectural changes in the heart may collectively contribute to increased cardiovascular disease risk in individuals exposed to incense smoke. Increased gene expressions of CYP1A1 and CYP1A2 may be instrumental in the incense smoke-induced oxidative stress and inflammation. Thus, incense smoke can be considered as a potential environmental pollutant and its long-term exposure may negatively impact human health.

The relationship between a Mediterranean diet and circulating adiponectin levels is influenced by cigarette smoking.

AIM: Adherence to a Mediterranean diet has been shown to lower the risk of developing several chronic diseases. The ability to augment circulating adiponectin levels is proposed as an underlying mechanism mediating the beneficial effects of this diet. We aimed to examine whether the positive relationship between the Mediterranean diet and adiponectin is altered by cigarette smoking, taking potential confounders into consideration. METHODS: Plasma adiponectin levels were enzymatically measured in 45 never smokers, 61 smokers and 34 ex-smokers who adhered to a Mediterranean style diet and in 41 never smokers who did not adhere to the diet. RESULTS: Plasma adiponectin levels increased significantly in nonsmoking diet adherents compared to nonsmoking non-diet adherents. Among the diet adherents adiponectin decreased significantly in both moderate and heavy smokers compared to never smokers and significantly increased in quitters compared to smokers. Multiple regression analysis, controlling for age, obesity, Mediterranean diet and insulin resistance revealed an independent inverse association of smoking with adiponectin. Adiponectin levels remained significant and similar in subjects stratified according to age (50 years), BMI (25 kg/m(2)) and HOMA-IR (1.6). CONCLUSIONS: Despite its positive effects on adiponectin, the Mediterranean diet failed to negate the adiponectin-lowering effect of cigarette smoking, demonstrating the profound and independent capacity of cigarette smoke to negatively influence human health.