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Interspecies variation in the susceptibility of adult Pacific salmon to toxic urban stormwater runoff
2018
McIntyre, Jenifer K. | Lundin, Jessica I. | Cameron, James R. | Chow, Michelle I. | Davis, Jay W. | Incardona, John P. | Scholz, Nathaniel L.
Adult coho salmon (Oncorhynchus kisutch) prematurely die when they return from the ocean to spawn in urban watersheds throughout northwestern North America. The available evidence suggests the annual mortality events are caused by toxic stormwater runoff. The underlying pathophysiology of the urban spawner mortality syndrome is not known, and it is unclear whether closely related species of Pacific salmon are similarly at risk. The present study co-exposed adult coho and chum (O. keta) salmon to runoff from a high traffic volume urban arterial roadway. The spawners were monitored for the familiar symptoms of the mortality syndrome, including surface swimming, loss of orientation, and loss of equilibrium. Moreover, the hematology of both species was profiled by measuring arterial pH, blood gases, lactate, plasma electrolytes, hematocrit, and glucose. Adult coho developed behavioral symptoms within a few hours of exposure to stormwater. Various measured hematological parameters were significantly altered compared to coho controls, indicating a blood acidosis and ionoregulatory disturbance. By contrast, runoff-exposed chum spawners showed essentially no indications of the mortality syndrome, and measured blood hematological parameters were similar to unexposed chum controls. We conclude that contaminant(s) in urban runoff are the likely cause of the disruption of ion balance and pH in coho but not chum salmon. Among the thousands of chemicals in stormwater, future forensic analyses should focus on the gill or cardiovascular system of coho salmon. Because of their distinctive sensitivity to urban runoff, adult coho remain an important vertebrate indicator species for degraded water quality in freshwater habitats under pressure from human population growth and urbanization.
Afficher plus [+] Moins [-]Gallic acid suppresses inflammation and oxidative stress through modulating Nrf2-HO-1-NF-κB signaling pathways in elastase-induced emphysema in rats
2021
Sohrabi, Farzaneh | Dianat, Mahin | Badavi, Mohammad | Radan, Maryam | Mard, Seyyed Ali
Emphysema is associated with an abnormal airspace enlargement distal to the terminal bronchioles accompanied by destructive changes in the alveolar walls and chronic inflammation. Air pollution can cause respiratory diseases such as chronic obstructive pulmonary disease (COPD) and emphysema in urban areas. As a natural antioxidant compound, gallic acid may be effective in controlling inflammation and preventing disease progression. In this research, we investigated the protective role of gallic acid in the inflammatory process and the possible signaling pathway in the elastase-induced emphysema. Forty-eight rats were divided into six different groups including the following: control, gallic acid (7.5, 15, and 30 mg/kg), porcine pancreatic elastase (PPE), and PPE+gallic acid 30 mg/kg. Oxidative stress indexes such as malondialdehyde and antioxidant enzyme activity were measured in all groups. The gene expression levels of heme oxygenase-1 (HO-1), nuclear factor (erythroid-derived 2)-like 2 (Nrf2), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) were determined as key regulators of antioxidant and inflammation system. The PPE group showed pulmonary edema and a significant change in arterial blood gas values, which was associated with decreased antioxidant activity of enzymes and changes in NF-κB, HO-1, and Nrf2 gene expression in comparison to the control group. Co-treatment with gallic acid preserved all these changes approximately to the normal levels. The results confirmed that elastase-induced emphysema leads to lung injuries, which are associated with oxidative stress and inflammation. Also, the results suggested that gallic acid as a natural antioxidant agent can modulate the Nrf2 signaling pathway to protect the lung against elastase-induced emphysema. Therefore, we documented the evidence for the importance of NF-κB inhibitors and Nrf2 activators as a target for new treatments in respiratory dysfunction caused by oxidative agents.
Afficher plus [+] Moins [-]Air quality improvement during 2010 Asian games on blood coagulability in COPD patients
2016
Zhang, Zili | Wang, Jian | Guo, Meihua | Xiong, Mingmei | Zhou, Qipeng | Li, Defu | Shu, Jiaze | Lu, Wenju | Sun, Dejun
Exposure to elevated levels of ambient air pollutants can lead to adverse cardiovascular effects. Perturbation of the coagulation balance is one of the potential mechanisms. However, evidence regarding the impact of improvement in air pollution on blood coagulability in COPD patients has never been reported. Coagulation processes are known to be of relevance for cardiovascular pathology; therefore, this study aimed to investigate the association of short-term air pollution exposure with blood marker (D-dimer) of coagulation. A 3-year (through the Asian game) cohort study based on the GIRD COPD Biobank Project was conducted in 36 COPD patients to estimate whether changes in measurements of D-dimer were associated with changes in pollutant concentration, comparing for 51 intervention days (November 1–December 21) in 2010 with the same calendar date of baseline years (2009 and 2011). Daily mean concentrations of air pollutants and meteorological variables were measured during the time. Daily PM₁₀ decreased from 65.86 μg/m³ during the baseline period to 62.63 μg/m³ during the Asian Games period; daily NO₂ decreased from 51.33 to 42.63 μg/m³. SO₂ and other weather variables did not differ substantially. We did not observe statistically significant improvements in D-dimer levels by 9.86 % from a pre-Asian game mean of 917 ng/ml to a during-Asian game mean of 1007 ng/ml, platelet number by 11.66 %, PH by −0.15 %, PCO₂ by −6.54 %, and PO₂ by −1.16 %. In the post-Asian game period, when pollutant concentrations increased, most outcomes approximated pre-Asian game levels, and similar effects were also demonstrated in D-dimer, platelet number, and arterial blood gas. For D-dimer and platelet number, we observed statistically significant increases associated with increases in NO₂ at lag 1–3 and SO₂ at lag 2–4. For PH, PCO₂, and PO₂, any significant effect was not demonstrated. This study gives no support to the hypothesis that reduction in air pollution levels during the 2010 Asian game is associated with activation of blood coagulation with COPD patients. However, one step forward has been made on the gap between improved air pollution and blood coagulability. Meanwhile, our study also provides evidence for the presence of a hypercoagulative state in systemic circulation in COPD patients. Additional studies employing other susceptible populations and endpoints are pending.
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