Impact of prolonged exposure to occasional and regular waterpipe smoke on cardiac injury, oxidative stress and mitochondrial dysfunction in male mice

Regular waterpipe smoking (Reg-WPS) is well recognized for its deleterious effect on the heart. However, there is a paucity of experimental studies on the impact of occasional waterpipe smoking (Occ-WPS), also known as nondaily smoking, versus Reg-WPS on cardiac homeostasis, and the mechanisms underlying these effects. Hence, we aimed, in the present study, to investigate the effect of Occ-WPS (30 min/day, 1 day/week) versus Reg-WPS (30 min/day, 5 days/week) for 6 months on systolic blood pressure (SBP), cardiac injury, oxidative markers, chemokines, proinflammatory cytokines, DNA damage and mitochondrial function compared with air (control) exposed mice. Our results show that SBP was increased following exposure to either Occ-WPS or Reg-WPS compared with air-exposed mice. Moreover, we found that only Reg-WPS induced a significant elevation in the levels of troponin I, brain natriuretic peptide, lactate dehydrogenase, and creatine phosphokinase. However, the atrial natriuretic peptide (ANP) was significantly increased in both Occ-WPS and Reg-WPS groups. Compared with air-exposed mice, the levels of lipid peroxidation, reduced glutathione and monocyte chemoattractant protein-1 were only significantly augmented in the Reg-WPS. However, catalase, superoxide dismutase, and CXCL1 were significantly increased in both Occ-WPS and Reg-WPS. The concentrations of the adhesion molecules E-selectin, vascular cell adhesion molecule-1, and intercellular adhesion molecule-1 were solely elevated in the heart of mice exposed to Reg-WPS. Similarly, the concentrations of interleukin-1β and tumor necrosis factor α were only significantly augmented in the Reg-WPS. However, both Occ-WPS and Reg-WPS triggered significant augmentation in the levels of IL17 and DNA damage compared to the control groups. Furthermore, while Occ-WPS induced a slight but statistically insignificant elevation in the concentrations of mammalian targets of rapamycin and nuclear factor erythroid-derived 2-like 2 (Nrf2) expression, Reg-WPS exposure increased their levels substantially, in addition to p53 and mitochondrial complexes II & III, and IV activities compared with air-exposed mice. In conclusion, our findings show that while the long-term Occ-WPS exposure induced an elevation of SBP, ANP, antioxidant enzymes, IL17, CXCL1, and cardiac DNA damage, Reg-WPS exposure was consistently associated with the elevation of SBP and occurrence of cardiac damage, inflammation, oxidative stress, DNA damage and mitochondrial dysfunction

Comparative Study on the Chronic Vascular Responses Induced by Regular Versus Occasional Waterpipe Smoke Inhalation in Mice

BACKGROUND/AIMS: Waterpipe smoke (WPS) is the second most prevalent form of smoking in the world. There are ample evidences about the vascular alterations caused by regular WPS (Reg-WPS). Nonetheless, comparison of the chronic vascular response induced by regular versus occasional WPS (Occ-WPS) exposure is very scarce. METHODS: We investigated, in BALB/c mice, the effects of Occ-WPS (30 minutes/day, 1 day/week) versus Reg-WPS (30 minutes/day, 5 days/week) for 6 months on thrombogenicity and platelet aggregation in vivo and in vitro. Moreover, various markers of endothelial integrity, inflammation and oxidative stress were assessed by enzyme-linked immunosorbent assay and colorimetric assay. Control mice were exposed to air. RESULTS: Our results showed that either Occ-WPS or Reg-WPS exposure shortened the thrombotic time in pial microvessels in vivo. Moreover, in pial venules, this effect was more marked in Reg-WPS group (-47%) compared with Occ-WPS (-34%). Similarly, exposure to either Occ-WPS or Reg-WPS reduced the prothrombin time and activated partial thromboplastin time. Platelet count was increased only in Reg-WPS exposure. Exposure to either Occ-WPS or Reg-WPS induced platelet aggregation in vitro. In addition, there was a statistically significant difference between Occ-WPS and Reg-WPS groups in platelet count and aggregation. Plasma concentration of tissue factor (+98%), P-selectin (+14%) and E-selectin (+16%) were significantly increased in Occ-WPS group compared with air exposed group. Likewise, compared with air group Reg-WPS caused an increase in concentration of tissue factor (+193%), P-selectin (+21%) and E-selectin (+42%). Nevertheless, only Reg-WPS induced a decrease (-38%) in the plasma concentration of tissue plasminogen activator. Notably, our results showed a statistically significant difference between Occ-WPS and Reg-WPS groups in the concentration of tissue factor. Erythrocyte numbers, hemoglobin concentration, hematocrit and lactate dehydrogenase activity were augmented only in Reg-WPS group compared with either control or Occ-WPS groups. Likewise, only Reg-WPS induced an increase in proinflammatory cytokines, tumor necrosis factor-α and interleukin-1β compared with either control or Occ-WPS groups. However, markers of oxidative stress including 8-isoprostane and total antioxidants were enhanced in both Occ-WPS and Reg-WPS compared with control group. CONCLUSION: Our data confirm the vascular toxicity of the chronic Reg-WPS exposure and shows that even occasional chronic exposure to WPS caused thrombosis, platelet aggregation, endothelial alterations and oxidative stress. The latter findings are an additional cause of concern about the long-term toxicity of occasional waterpipe smoking

Cardiac Inflammation, Oxidative Stress, Nrf2 Expression, and Coagulation Events in Mice with Experimental Chronic Kidney Disease

Chronic kidney disease (CKD) is known to be associated with cardiovascular dysfunction. Dietary adenine intake in mice is also known to induce CKD. However, in this experimental model, the mechanisms underlying the cardiotoxicity and coagulation disturbances are not fully understood. Here, we evaluated cardiac inflammation, oxidative stress, DNA damage, and coagulation events in mice with adenine (0.2% w/w in feed for 4 weeks)-induced CKD. Control mice were fed with normal chow for the same duration. Adenine increased water intake, urine output, relative kidney weight, the plasma concentrations of urea and creatinine, and the urinary concentrations of kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin. It also decreased the body weight and creatinine clearance, and caused kidney DNA damage. Renal histological analysis showed tubular dilation and damage and neutrophilic influx. Adenine induced a significant increase in systolic blood pressure and the concentrations of troponin I, tumor necrosis factor-α, and interleukin-1β in heart homogenates. It also augmented the levels of markers of lipid peroxidation measured by malondialdehyde production and 8-isoprostane, as well as the antioxidants superoxide dismutase and catalase. Immunohistochemical analysis of the hearts showed that adenine increased the expression of nuclear factor erythroid-derived 2-like 2 by cardiomyocytes. It also caused cardiac DNA damage. Moreover, compared with the control group, adenine induced a significant increase in the number of circulating platelet and shortened the thrombotic occlusion time in pial arterioles and venules in vivo, and induced a significant reduction in the prothrombin time and activated partial thromboplastin time. In conclusion, the administration of adenine in mice induced CKD-associated cardiac inflammation, oxidative stress, Nrf2 expression, and DNA damage. It also induced prothrombotic events in vivo. Therefore, this model can be satisfactorily used to study the cardiac pathophysiological events in subjects with CKD and the effect of drug treatment thereon

The in Vitro Effect of Polyvinylpyrrolidone and Citrate Coated Silver Nanoparticles on Erythrocytic Oxidative Damage and Eryptosis

Background/Aims: Silver nanoparticles (AgNPs) are increasingly used as antimicrobial agents and drug carriers in various biomedical fields. AgNPs can encounter erythrocytes either directly following intravenous injection, or indirectly via translocation from the site of administration. However, information regarding the pathophysiological effects and possible mechanism of action of AgNPs on the erythrocytes are still inadequately studied. Thus, the aim of our study was to investigate the mechanism underlying the effect of coating and concentration of AgNPs on mouse erythrocytes in vitro. Methods: We studied the interaction of polyvinylpyrrolidone (PVP) and citrate (CT) coated AgNPs (10 nm) at various concentrations (2.5, 10, 40 µg/ml) with mouse erythrocytes in vitro using various techniques including transmission electron microscopy (TEM), hemolysis, and colorimetric measurement of markers of oxidative stress comprising malondialdehyde (MDA), reduced glutathione (GSH), and catalase (CAT). Intracellular calcium (Ca2+) was determined using Fura 2AM fluorescence. Annexin V was quantified using ELISA and the caspase 3 was determined both flurometrically and by western blot technique. Results: Following incubation of the erythrocytes with AgNPs, both PVP- and CT- AgNPs induced significant and dose - dependent increase in hemolysis. TEM revealed that both PVP- and CT- AgNPs were taken up by erythrocytes. The erythrocyte susceptibility to lipid peroxidation measured by MDA was significantly increased in both PVP-and CT- AgNPs. The concentration of GSH and CAT activity were significantly decreased by both types of AgNPs. Additionally, PVP- and CT- AgNPs significantly increased intracellular Ca2+ in a dose -dependent manner. Likewise, the concentration of the cellular protein annexin V was significantly and dose - dependently enhanced by both types of AgNPs. Furthermore, PVP- and CT- AgNPs induced significant increase in calpain activity in incubated erythrocytes. Conclusion: We conclude that both PVP- and CT- AgNPs causes hemolysis, and are taken up by erythrocytes. Moreover, we demonstrated that AgNPs induces oxidative stress and eryptosis. These findings provide evidence for the potential pathophysiological effect of PVP-and CT- AgNPs on erythrocyte physiology

Gum Arabic Ameliorates Impaired Coagulation and Cardiotoxicity Induced by Water-Pipe Smoke Exposure in Mice

Water-pipe smoking (WPS) is prevalent in the East and elsewhere. WPS exposure is known to induce thrombosis and cardiovascular toxicity involving inflammation and oxidative stress. Here, we have investigated the effect of Gum Arabic (GA), a prebiotic with anti-oxidant, anti-inflammatory and cytoprotective properties, on WPS exposure (30 min/day for 1 month) on coagulation and cardiac homeostasis, and their possible underlying mechanisms in mice. Animals received either GA in drinking water (15%, w/v) or water only for the entire duration of study. GA significantly mitigated thrombosis in pial microvessels in vivo, platelet aggregation in vitro, and the shortening of prothrombin time induced by WPS exposure. The increase in plasma concentrations of fibrinogen, plasminogen activator inhibitor-1 and markers of lipid peroxidation, 8-isoprostane and malondialdehyde, induced by WPS were significantly reduced by GA administration. Moreover, WPS exposure induced a significant increase in systolic blood pressure and the concentrations of the pro-inflammatory cytokines tumor necrosis factor-α and interleukin 1β in heart homogenates. GA significantly alleviated these effects, and prevented the decrease of reduced glutathione, catalase and total nitric oxide levels in heart homogenates. Immunohistochemical analysis of the hearts showed that WPS exposure increased nuclear factor erythroid-derived 2-like 2 (Nrf2) expressions by cardiac myocytes and endothelial cells, and these effects were potentiated by the combination of GA and WPS. WPS also increased DNA damage and cleaved caspase 3, and GA administration prevented these effects. Our data, obtained in experimental murine model of WPS exposure, show that GA ameliorates WPS-induced coagulation and cardiovascular inflammation, oxidative stress, DNA damage and apoptosis, through a mechanism involving Nrf2 activation

Exercise Training Mitigates Water Pipe Smoke Exposure-Induced Pulmonary Impairment via Inhibiting NF- κ

Water pipe smoking is a tobacco smoking method commonly used in Eastern countries and is gaining popularity in Europe and North America, in particular among adolescents and young adults. Several clinical and experimental studies have reported that exposure to water pipe smoke (WPS) induces lung inflammation and impairment of pulmonary function. However, the mechanisms of such effects are not understood, as are data on the possible palliative effect of exercise training. The present study evaluated the effects of regular aerobic exercise training (treadmill: 5 days/week, 40 min/day) on subchronic exposure to WPS (30 minutes/day, 5 days/week for 2 months). C57BL/6 mice were exposed to air or WPS with or without exercise training. Airway resistance measured using forced oscillation technique was significantly and dose-dependently increased in the WPS-exposed group when compared with the air-exposed one. Exercise training significantly prevented the effect of WPS on airway resistance. Histologically, the lungs of WPS-exposed mice had focal moderate interstitial inflammatory cell infiltration consisting of neutrophil polymorphs, plasma cells, and lymphocytes. There was a mild increase in intra-alveolar macrophages and a focal damage to alveolar septae in some foci. Exercise training significantly alleviated these effects and also decreased the WPS-induced increase of tumor necrosis factor α and interleukin 6 concentrations and attenuated the increase of 8-isoprostane in lung homogenates. Likewise, the lung DNA damage induced by WPS was significantly inhibited by exercise training. Moreover, exercise training inhibited nuclear factor kappa-B (NF-κB) expression induced by WPS and increased that of nuclear factor erythroid 2-related factor 2 (Nrf2). Our findings suggest that exercise training significantly mitigated WPS-induced increase in airway resistance, inflammation, oxidative stress, and DNA damage via mechanisms that include inhibiting NF-κB and activating Nrf2 signalling pathways