Air-exposed Group Research Articles

The respiratory health effects of acute in vivo diesel and biodiesel exhaust in a mouse model

BackgroundBiodiesel, a renewable diesel fuel that can be created from almost any natural fat or oil, is promoted as a greener and healthier alternative to commercial mineral diesel without the supporting experimental data to back these claims. The aim of this research was to assess the health effects of acute exposure to two types of biodiesel exhaust, or mineral diesel exhaust or air as a control in mice. Male BALB/c mice were exposed for 2-hrs to diluted exhaust obtained from a diesel engine running on mineral diesel, Tallow biodiesel or Canola biodiesel. A room air exposure group was used as a control. Twenty-four hours after exposure, a variety of respiratory related end point measurements were assessed, including lung function, responsiveness to methacholine and airway and systemic immune responses. ResultsTallow biodiesel exhaust exposure resulted in the greatest number of significant effects compared to Air controls, including increased airway hyperresponsiveness (178.1 ± 31.3% increase from saline for Tallow biodiesel exhaust exposed mice compared to 155.8 ± 19.1 for Air control), increased airway inflammation (63463 ± 13497 cells/mL in the bronchoalveolar lavage of Tallow biodiesel exhaust exposed mice compared to 40561 ± 11800 for Air exposed controls) and indications of immune dysregulation. In contrast, exposure to Canola biodiesel exhaust resulted in fewer significant effects compared to Air controls with a slight increase in airway resistance at functional residual capacity and indications of immune dysregulation. Exposure to mineral diesel exhaust resulted in significant effects between that of the two biodiesels with increased airway hyperresponsiveness and indications of immune dysregulation. ConclusionThese data show that a single, brief exposure to biodiesel exhaust can result in negative health impacts in a mouse model, and that the biological effects of exposure change depending on the feedstock used to make the biodiesel.

Recapitulation of human pathophysiology and identification of forensic biomarkers in a translational model of chlorine inhalation injury.

Chlorine gas (Cl2) has been repeatedly used as a chemical weapon, first in World War I and most recently in Syria. Life-threatening Cl2 exposures frequently occur in domestic and occupational environments, and in transportation accidents. Modeling the human etiology of Cl2-induced acute lung injury (ALI), forensic biomarkers, and targeted countermeasures development have been hampered by inadequate large animal models. The objective of this study was to develop a translational model of Cl2-induced ALI in swine to understand toxico-pathophysiology and evaluate whether it is suitable for screening potential medical countermeasures and to identify biomarkers useful for forensic analysis. Specific pathogen-free Yorkshire swine (30-40 kg) of either sex were exposed to Cl2 (≤240 ppm for 1 h) or filtered air under anesthesia and controlled mechanical ventilation. Exposure to Cl2 resulted in severe hypoxia and hypoxemia, increased airway resistance and peak inspiratory pressure, and decreased dynamic lung compliance. Cl2 exposure resulted in increased total leucocyte and neutrophil counts in bronchoalveolar lavage fluid, vascular leakage, and pulmonary edema compared with the air-exposed group. The model recapitulated all three key histopathological features of human ALI, such as neutrophilic alveolitis, deposition of hyaline membranes, and formation of microthrombi. Free and lipid-bound 2-chlorofatty acids and chlorotyrosine-modified proteins (3-chloro-l-tyrosine and 3,5-dichloro-l-tyrosine) were detected in plasma and lung tissue after Cl2 exposure. In this study, we developed a translational swine model that recapitulates key features of human Cl2 inhalation injury and is suitable for testing medical countermeasures, and validated chlorinated fatty acids and protein adducts as biomarkers of Cl2 inhalation.NEW & NOTEWORTHY We established a swine model of chlorine gas-induced acute lung injury that exhibits several features of human acute lung injury and is suitable for screening potential medical countermeasures. We validated chlorinated fatty acids and protein adducts in plasma and lung samples as forensic biomarkers of chlorine inhalation.

Integration of metagenome and metabolome analysis reveals the correlation of gut microbiota, oxidative stress, and inflammation in Coilia nasus under air exposure stress and salinity mitigation

Due to the strong response to air exposure, high mortality was occurred in Coilia nasus. Previous studies reported that 10 ‰ NaCl could significantly reduce mortality in C. nasus under air exposure. To investigate the mechanisms that 10 ‰ NaCl can alleviate stress, community structure and metabolism of the intestinal flora of C. nasus were detected via metagenome and metabolome. In this study, C. nasus were divided into control group (C), air exposure group without 10 ‰ NaCl (AE), and air exposure group with 10 ‰ NaCl (AES). After air exposure stress and salinity mitigation, the mortality, intestinal microorganisms, metabolites, and physiological biomarkers were analyzed. The results showed that the mortality rate of C. nasus was reduced after salinity reduction; the antioxidant capacity was elevated compared to the AE group; and anti-inflammatory capacity was increased in the AES group compared to the AE group. Metagenomic sequencing results showed that the levels of harmful bacteria (E. coli, Aeromonas) in the Candida nasus gut increased after air exposure; beneficial bacteria (Actinobacteria, Corynebacteria) in the C. nasus gut increased after salinity reduction. Metabolomics analyses showed that AE decreased the expression of beneficial metabolites and increased the expression of harmful metabolites; AES increased beneficial metabolites and decreased harmful metabolites. Correlation analysis showed that in the AE group, beneficial metabolites were negatively correlated with oxidative stress and inflammatory response, while harmful metabolites were positively correlated with oxidative stress and inflammatory response, and were associated with bacterial communities such as Gillisia, Alkalitalia, Avipoxvirus, etc.; the correlation of metabolites with oxidative stress and inflammatory response was opposite to that of AE in the case of AES, and was associated with Lentilactobacillus, Cyanobacterium, and other bacterial communities. Air exposure caused damage to Candida rhinoceros and 10 ‰ salinity was beneficial in alleviating C. nasus stress. These results will provide new insights into methods and mechanisms to mitigate stress in fish.

Desipramine ameliorates fine particulate matter-induced hepatic insulin resistance by modulating the ceramide metabolism in mice

Recent research has highlighted a correlation between exposure to ambient fine particulate matter (PM2.5) and the development of systemic insulin resistance (IR) along with an elevated risk of diabetes. Ceramide has emerged as one of the pathogenic mechanisms contributing to IR. The inhibition of acid sphingomyelinase (ASMase) activity by desipramine (DES) has been shown to effectively reduce ceramide levels. In the present study, 24 female C57BL/6 N mice were randomized into one of the four groups: the filtered air exposure (FA) group, the concentrated PM2.5 exposure (PM) group, the concentrated PM2.5 treated with low-dose DES (DL) group, and the concentrated PM2.5 treated with high-dose DES (DH) group. The PM, DL and DH groups were exposed to PM2.5 for an 8-week period within a whole-body exposure system. The study encompassed extensive examinations of glucose homeostasis, liver lipid profile, ceramide pathway, and insulin signaling pathway. Our results demonstrated that PM2.5 exposure caused impaired glucose tolerance, elevated ceramide levels, increased phosphorylation PP2A, reduced Akt phosphorylation, and hindered GLUT2 expression. Remarkably, DES administration mitigated PM2.5-induced IR by effectively lowering ceramide levels. In conclusion, the reduction of ceramide levels by DES may be a promising therapeutic strategy for coping PM2.5-induced IR.

Waterpipe smoke inhalation induces lung injury and aortic endothelial dysfunction in mice.

Waterpipe tobacco smoking (WPS) inhalation has been shown to trigger endothelial dysfunction and atherosclerosis. However, the mechanisms underlying these effects are still unknown. Here, we assessed the impact and underlying mechanism of WPS exposure for one month on endothelial dysfunction using aortic tissue of mice. The duration of the session was 30 min/day and 5 days/week. Control mice were exposed to air. Inhalation of WPS induced an increase in the number of macrophages and neutrophils and the concentrations of protein, tumor necrosis factor alpha (TNF alpha), interleukin (IL)-1beta, and glutathione in bronchoalveolar lavage fluid. Moreover, the concentrations of proinflammatory cytokines (TNF alpha, IL-6 and IL-1beta), adhesion molecules (intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin and P-selectin) and markers of oxidative stress (lipid peroxidation, glutathione, superoxide dismutase and nitric oxide) in aortic homogenates of mice exposed to WPS were significantly augmented compared with air exposed mice. Likewise, the concentration of galectin-3 was significantly increased in the aortic homogenates of mice exposed to WPS compared with control group. WPS inhalation induced vascular DNA damage assessed by comet assay and apoptosis characterized by a significant increase in cleaved caspase-3. While the aortic expression of phosphorylated nuclear factor kappaB (NF-kappaB) was significantly increased following WPS inhalation, the concentration of sirtuin 1 (SIRT1) was significantly decreased in WPS group compared with air-exposed group. In conclusion, our study provided evidence that WPS inhalation triggers lung injury and endothelial inflammation, oxidative stress and apoptosis which were associated with nuclear factor-kappaB activation and SIRT1 down-regulation.

Neuroinflammation, Oxidative Stress, Apoptosis, Microgliosis and Astrogliosis in the Cerebellum of Mice Chronically Exposed to Waterpipe Smoke

Waterpipe smoking (WPS) is prevalent in Asian and Middle Eastern countries and has recently gained worldwide popularity, especially among youth. WPS has potentially harmful chemicals and is associated with a wide range of adverse effects on different organs. However, little is known regarding the impact of WPS inhalation on the brain and especially on the cerebellum. Presently, we aimed at investigating inflammation, oxidative stress and apoptosis as well as microgliosis and astrogliosis in the cerebellum of BALB/C mice chronically (6 months) exposed to WPS compared with air-exposed mice (control). WPS inhalation augmented the concentrations of proinflammatory cytokines tumor necrosis factor, interleukin (IL)-6 and IL-1β in cerebellar homogenates. Likewise, WPS increased oxidative stress markers including 8-isoprostane, thiobarbituric acid reactive substances and superoxide dismutase. In addition, compared with the air-exposed group, WPS caused an increase in the oxidative DNA damage marker, 8-hydroxy-2'-deoxyguanosine, in cerebellar homogenates. Similarly, in comparison with the air group, WPS inhalation elevated the cerebellar homogenate levels of cytochrome C, cleaved caspase-3 and nuclear factor-κB (NF-κB). Immunofluorescence analysis of the cerebellum showed that WPS exposure significantly augmented the number of ionized calcium-binding adaptor molecule 1 and glial fibrillary acidic protein-positive microglia and astroglia, respectively. Taken together, our data show that chronic exposure to WPS is associated with cerebellar inflammation, oxidative stress, apoptosis, microgliosis and astrogliosis. These actions were associated with a mechanism involving NF-κB activation.

In vivo measurements of lung function using respiratory-gated micro-computed tomography in a smoke-exposure model of chronic obstructive pulmonary disease.

We hypothesize that in vivo respiratory-gated micro computed tomography (micro-CT) imaging can noninvasively provide structural and functional information about the lungs in a cigarette-exposure model of chronic obstructive pulmonary disease in mice. Female C57BL/6 mice were exposed to cigarette smoke or ambient air for 1, 3, or 6 months. Each mouse received a respiratory-gated micro-CT scan at baseline and another scan following the exposure period, while anaesthetized and free-breathing. Images were obtained representing end-expiration and peak inspiration, and measurements were performed to characterize the lung structure and compute functional metrics. Following the final micro-CT session, the mice were euthanized and the lungs prepared for histology. Following 6 months of smoke-exposure, the mice exhibited larger increases in end-expiration lung volume and functional residual capacity, and a reduction in weight gain when compared with air-exposed mice. The histogram of CT numbers in the lung obtained during end-expiration also showed a shift to lower CT numbers following 6 months of smoke-exposure, indicating increased air content within the lungs. The metrics suggested air-trapping in the lung, which is consistent with emphysema. In the 3-month exposure group, only the reduction in weight gain was significant compared with the air-exposed group. Histological analysis confirmed that the 6-month smoke-exposed mice likely developed centrilobular emphysema as measured by the mean linear intercept. Respiratory-gated micro-CT imaging of free-breathing mice at multiple respiratory phases is noninvasive and provides additional information about lung structure and function that complements postmortem techniques and could be used to monitor changes over time.

Waterpipe smoke inhalation potentiates cardiac oxidative stress, inflammation, mitochondrial dysfunction, apoptosis and autophagy in experimental hypertension

Cigarette smoking worsens the health of hypertensive patients. However, less is known about the actions and underlying mechanisms of waterpipe smoke (WPS) in hypertension. Therefore, we evaluated the effects of WPS inhalation in mice made hypertensive (HT) by infusing angiotensin II for six weeks. On day 14 of the infusion of angiotensin II or vehicle (normotensive; NT), mice were exposed either to air or WPS for four consecutive weeks. Each session was 30 min/day and 5 days/week. In NT mice, WPS increased systolic blood pressure (SBP) compared with NT air-exposed group. SBP increase was elevated in HT+WPS group versus either HT+air or NT+WPS. Similarly, the plasma levels of brain natriuretic peptide, C-reactive protein, 8-isoprostane and superoxide dismutase were increased in HT+WPS compared with either HT+air or NT+WPS. In the heart tissue, several markers of oxidative stress and inflammation were increased in HT+WPS group vs the controls. Furthermore, mitochondrial dysfunction in HT+WPS group was more affected than in the HT+air or HT+WPS groups. WPS inhalation in HT mice significantly increased cardiac DNA damage, cleaved caspase 3, expression of the autophagy proteins beclin 1 and microtubule-associated protein light chain 3B, and phosphorylated nuclear factor κ B, compared with the controls. Compared with HT+air mice, heart histology of WPS-exposed HT mice showed increased cardiomyocyte damage, neutrophilic and lymphocytic infiltration and focal fibrosis. We conclude that, in HT mice, WPS inhalation worsened hypertension, cardiac oxidative stress, inflammation, mitochondrial dysfunction, DNA damage, apoptosis and autophagy. The latter effects were associated with a mechanism involving NF-κB activation.

Hawthorn total flavonoids ameliorate ambient fine particulate matter-induced insulin resistance and metabolic abnormalities of lipids in mice

Recent studies have shown a strong correlation between ambient fine particulate matter (PM2.5) exposure and diabetes risk, including abnormal lipid accumulation and systemic insulin resistance (IR). Hawthorn total flavonoids (HF) are the main groups of active substances in Hawthorn, which showed anti-hyperlipidemic and anti-hyperglycemic effects. Therefore, we hypothesized that HF may attenuate PM2.5-induced IR and abnormal lipid accumulation. Female C57BL/6 N mice were randomly assigned to the filtered air exposure (FA) group, concentrated PM2.5 exposure (PM) group, PM2.5 exposure maintained on a low-dose HF diet (LHF) group, and PM2.5 exposure maintained on a high-dose HF diet (HHF) group for an 8-week PM2.5 exposure using a whole-body exposure device. Body glucose homeostasis, lipid profiles in the liver and serum, and enzymes responsible for hepatic lipid metabolism were measured. We found that exposure to PM2.5 impaired glucose tolerance and insulin sensitivity. In addition, triacylglycerol (TAG) in serum elevated, whereas hepatic TAG levels were decreased after PM2.5 exposure, accompanied by inhibited fatty acid uptake, lipogenesis, and lipolysis in the liver. HF administration, on the other hand, balanced the hepatic TAG levels by increasing fatty acid uptake and decreasing lipid export, leading to alleviated systemic IR and hyperlipidemia in PM2.5-exposed mice. Therefore, HF administration may be an effective strategy to protect against PM2.5-induced IR and metabolic abnormalities of lipids.

Effects of ozone sub-chronic exposure on lncRNA expression profiles in rat heart

Objective: This article aims to observe the changes in long noncoding RNA (lncRNA) expression profiles in rat hearts after ozone sub-chronic exposure. To provide scientific data to explore the role and mechanism of differentially expressed lncRNA in damaged hearts caused by ozone sub-chronic exposure. Methods: Eighteen Wistar rats were randomly divided into filtered air and ozone exposure groups, with nine rats in each group. The rats in filtered air group were exposed to filtered air, while the rats in ozone exposure group were exposed to ozone at 0.5 ppm(0.980 mg/m3)for 90 days at a frequency of 6 hours per day. After ozone exposure, cardiac tissues were collected and the total RNA was extracted. The expression level of lncRNA in the hearts of two groups was detected by microarray and qRT-PCR method and the potential functions of the differentially expressed lncRNA were analyzed by bioinformatics. Results: Compared with the filtered air group, lncRNA's expression profile was significantly altered in the rat hearts of ozone exposure group. A total of 167 lncRNA were up-regulated significantly and 64 lncRNA were down-regulated significantly. GO analysis indicated that the up-regulated lncRNA might involve in the process of regulating growth and development, and the down-regulated lncRNA might participate in nutrient catabolic. KEGG results showed that the up-regulated lncRNA might be involved in regulating the PI3K-Akt signaling pathway. The down-regulated lncRNA might regulate the metabolic processes of various vitamins and main energy-supplying substances. Conclusion: Ozone sub-chronic exposure can cause changes in the expression profile of lncRNA in rat hearts, which may regulate the effects of ozone sub-chronic exposure on the heart through the metabolism of energy and nutrients.

Inhaled Crystalline Silica Reduces Systemic Inflammation Induced by a Western Diet in the F344 Rat

Adipose tissue has a central role in the maintenance of whole-body energy homeostasis. In healthy individuals, adipose tissue releases adipokines, which contribute to maintenance of insulin sensitivity and lipid and glucose metabolism as well as the regulation of satiety and inflammation. Obesity disrupts adipocyte metabolism, which leads to chronic systemic inflammation and metabolic dysfunction (MetDys)(abdominal obesity, insulin resistance, dyslipidemia, hypertension and systemic inflammation), and are associated with impaired lung function, pulmonary hypertension, and asthma. Silicosis, an occupational lung disease, is caused by inhalation of respirable crystalline silica, which is characterized, in part, by chronic lung inflammation and fibrosis, and significant morbidity and mortality. The purpose of this study is to determine if silica inhalation, and silica inhalation combined with MetDys induced by consumption of a Western diet (WD), affects metabolic disorders as well. For this study, 6-wk-old male F344 rats were fed either a WD [fat 45% Kcal (lard 19.5%, soybean oil 3% by weight), carbohydrate 36.2% Kcal (sucrose 22.2% by weight), protein19% Kcal] or standard rat chow (STD) [fat 6.2% by weight, carbohydrate 45% by weight (grain sources), protein 18.0% by weight, fiber 4% by weight] for 16 wk to initate MetDys, followed by inhalation exposure to respirable crystalline silica (Min-U-Sil 5®, 15 mg/m3) or filtered air 6 h/day, 5 d/week, for 39 d. Endpoints were measured at 0, 4, and 8 wk post-exposure. Animals were maintained on their assigned diets throughout the study. WD increased body mass, abdominal girth, and fat pad weight; silica exposure had no effect on these parameters in STD or WD groups. At 8 wk post-exposure, silica reduced WD-induced increases in serum cholesterol, increased HDL compared to silica alone, and altered alkaline phosphatase, BUN, and BUN/creatine, but had no effect on fasting glucose. Insulin levels were altered by silica in the WD group at 0, 4 but not 8 wk. Leptin levels were decreased by silica exposure in both STD and WD groups. Silica inhalation increased tail arterial pulse frequency (Doppler method) in both STD and WD groups at 8 wk compared to pre-inhalation levels. Silica significantly reduced WD-induced serum inflammatory cytokines INF-γ, CXCL-1, TNF-α, IL-1β, IL-4, IL-5, IL-6, IL-10 and IL-13 compared to the WD air-exposed group at 8 wk post-exposure. Our results indicate that silica inhalation affects WD-induced adipose dysfunction, causing reduction of systemic inflammation and serum leptin in the F344 rat. MetDys-related conditions, including lipid profile, liver, kidney and arterial function, were altered by silica in WD-fed groups, although silica inhalation had no effect on WD-induced weight gain or fat pad mass. In conclusion, silica exposure does not increase the severity of WD-induced obesity but does alter changes in WD-induced organ function, including adipose endocrine function. Reduction of WD-induced inflammation by silica may be a result of a shift in the migration of immune cells to the lung, rather than the adipose tissue, thereby reducing adipose inflammation and subsequent systemic inflammation.

Effect of addition of salt on oxidant activity and apoptosis of Coilia nasus juveniles under air exposure stress

Air exposure, as a stressor, can cause death of most fish species in aquaculture. However, little has been known about the responses to the stress caused by air exposure. In the present study, the influence of addition of salt on mitigating the stress caused by air exposure was investigated in Coilia nasus juveniles for the first time. Five experimental groups (control (C), air exposure group without addition of salt (FAF), addition of salt after air exposure (FAS), addition of salt before air exposure (SAF), and addition of salt both before and after air exposure (SAS)) were analyzed in an acute air exposure stress model. The results showed that air exposure triggered high mortality; antioxidase activities and total antioxidant capacity were decreased; malondialdehyde (MDA) and lipid peroxide (LPO) were increased; and Caspase 3 expression was activated. The expression of genes associated with mitochondrial apoptosis (Caspase 9, Apaf1, Bax, Bcl-2), endoplasmic reticulum apoptosis (CHOP, PERK, ATF4), and death receptor apoptosis (CFLAR, TRADD) was activated after air exposure. Compared to FAF, mortality was decreased by 5-fold in the SAS group. Additionally, antioxidant activities were increased, and MDA and LPO levels were decreased. SAS could also inhibit expressions of the genes related to apoptosis. These results indicated that high mortality, oxidant stress, and apoptosis were caused by air exposure, but the addition of salt both before and after air exposure could significantly reduce mortality, inhibit oxidant stress and apoptosis. Our data demonstrated that the addition of salt both before and after air exposure would be an effective method to mitigate air exposure stress in C. nasus juveniles.

Isoflurane and low-level carbon monoxide exposures increase expression of pro-survival miRNA in neonatal mouse heart.

Anesthetics such as isoflurane are known to cause apoptosis in the developing mammalian brain. However, isoflurane may have protective effects on the heart via relieving ischemia and downregulating genes related to apoptosis. Ischemic preconditioning, e.g. through the use of low levels of carbon monoxide (CO), has promise in preventing ischemia-reperfusion injury and cell death. However, it is still unclear how it either triggers the stress response in neonatal hearts. For this reason, thirty-three microRNAs (miRNAs) known to be differentially expressed following anesthesia and/or ischemic or hypoxic heart damage were investigated in the hearts from neonatal mice exposed to isoflurane or low level of CO, using an air-exposed control group. Only miR-93-5p increased with isoflurane exposure, which may be associated with the suppression of cell death, autophagy, and inflammation. By contrast, twelve miRNAs were differentially expressed in the heart following CO treatment. Many miRNAs previously shown to be responsible for suppressing cell death, autophagy, and myocardial hypertrophy were upregulated (e.g., 125b-3p, 19-3p, and 21a-5p). Finally, some miRNAs (miR-103-3p, miR-1a-3p, miR-199a-1-5p) which have been implicated in regulating energy balance and cardiac contraction were also differentially expressed. Overall, this study demonstrated that CO-mediated miRNA regulation may promote ischemic preconditioning and cardioprotection based on the putative protective roles of the differentially expressed miRNAs explored herein and the consistency of these results with those that have shown positive effects of CO on heart viability following anesthesia and ischemia-reperfusion stress.

Cloning, functional characterization and expression analysis of nuclear factor erythroid-2-related factor-2 of golden pompano (Trachinotus ovatus) and its response to air-exposure

Nrf2 is an important component of Nrf2-ARE signaling pathway. However, information about Nrf2 in golden pompano (Trachinotus ovatus) is quiet limited. Thus, the full length of Nrf2 was cloned from T. ovatus in this study. The full-length cDNA sequence was 2376 bp in length and comprised of a 1848 bp ORF preceded by 123 bp 5′UTR, and followed by a 405 bp UTR. The putative amino acid sequence of the Nrf2 contained 615 residues, consisting of a conservative basic region leucin zipper. The N terminal portion of Nrf2 is rich in glutamic and aspartic acids and functioned as an acidic type of activation domain. The C terminus of the protein contained a region with heptad repeats of leucines. The phylogenetic tree showed that Seriola dumerili and T. ovatus were clustered as a branch, and combined with Mastacembelus armatus, Oreochromis niloticus and Takifugu rubripes. This branch of 5 species clustered with other branch of Oncorhynchus mykiss and Salmo salar. Nrf2 gene was predominantly expressed in liver and gut. The relative expression of Nrf2 in liver was significantly higher than that in brain, kidney, spleen and heart. After air-exposure, the expression level of HIF-1 alpha, keap1, Nrf2, HO-1, SOD and GSH-PX were significantly higher in air-exposure group than that in control group. This present study showed that Nrf2 plays a pivotal role in oxidative stress caused by air-exposure in T. ovatus, providing information about response to oxidative stress on the basis of the Nrf2-ARE pathway in T. ovatus.

Effect of hypoxia and air-breathing restricted on respiratory physiology of air-breathing loach (Paramisgurnus dabryanus).

This aim of this study was to determine the respiratory physiology response in the gill and gut of Paramisgurnus dabryanus under different breathing treatment patterns. The experimental design included the following three conditions: a control group without any stress treatments, an inhibited group with intestinal respiration inhibited, and an air-exposed group with gill respiration inhibited. The results indicated that the total static metabolic rate in the air-exposed group (188.92 ± 13.67 mg h-1 kg-1) was much higher than that of the other group after 7 days, decreased significantly after the first day of recovery (81.64 ± 7.85 mg h-1 kg-1). The air metabolic rate in the air-exposed group increased significantly after 7 days (P < 0.05). There was no significant difference among the groups. Histological observation on the gill and hindgut of P. dabryanus showed that the gill filament area of inhibited group became larger, while the gill structure of air exposed group showed some damage. The number of capillariesin the hindgut mucosal epithelial in air-exposed group showed a rapidly increase (P < 0.05). Likewise, the gas diffusion distance (1.24 ± 0.36 μm) became significantly shorter (P < 0.05). Lactate dehydrogenase activity of gill in the air-exposed group (846.68 ± 88.78 U mg-1 protein) significantly increased after 7 days whereas succinate dehydrogenase (1.02 ± 0.21 U mg-1 protein) and Na+/K+ ATPase (0.57 ± 0.20 U mg-1 protein) activity decreased significantly (P < 0.05). However, there was no significant change in the hindgut. After recovery, there was no significant difference in lactate dehydrogenase, succinate dehydrogenase, and Na+/K+ ATPase activity in the gill or hindgut in groups. P. dabryanus had a high viability in air-exposed condition. When recovery occurred under normoxic conditions, the physical levels of respiration returned back to the normal level quickly.

Prenatal Exposure to Electronic-Cigarette Aerosols Leads to Sex-Dependent Pulmonary Extracellular-Matrix Remodeling and Myogenesis in Offspring Mice.

Electronic-cigarette (e-cig) vaping is a serious concern, as many pregnant women who vape consider it safe. However, little is known about the harmful effects of prenatal e-cig exposure on adult offspring, especially on extracellular-matrix (ECM) deposition and myogenesis in the lungs of offspring. We evaluated the biochemical and molecular implications of maternal exposure during pregnancy to e-cig aerosols on the adult offspring of both sexes, with a particular focus on pulmonary ECM remodeling and myogenesis. Pregnant CD-1 mice were exposed to e-cig aerosols with or without nicotine, throughout gestation, and lungs were collected from adult male and female offspring. Compared with the air-exposed control group, female mice exposed to e-cig aerosols, with or without nicotine, demonstrated increased lung protein abundance of LEF-1 (lymphoid enhancer-binding factor 1), fibronectin, and E-cadherin, whereas altered E-cadherin and PPARγ (peroxisome proliferator-activated receptor γ) levels were observed only in males exposed to e-cig aerosols with nicotine. Moreover, lipogenic and myogenic mRNAs were dysregulated in adult offspring in a sex-dependent manner. PAI-1 (plasminogen activator inhibitor-1), one of the ECM regulators, was significantly increased in females exposed prenatally to e-cig aerosols with nicotine and in males exposed to e-cig aerosols compared with control animals exposed to air. MMP9 (matrix metalloproteinase 9), a downstream target of PAI-1, was downregulated in both sexes exposed to e-cig aerosols with nicotine. No differences in lung histology were observed among any of the treatment groups. Overall, adult mice exposed prenatally to e-cig aerosols could be predisposed to developing pulmonary disease later in life. Thus, these findings suggest that vaping during pregnancy is unsafe and increases the propensity for later-life interstitial lung diseases.

The influence of oxygen concentration during embryo culture on obstetric and neonatal outcomes: a secondary analysis of a randomized controlled trial.

Does oxygen concentration during 3-day embryo culture affect obstetric and neonatal outcomes? Oxygen concentration during 3-day embryo culture does not seem to affect the obstetric and neonatal outcomes measured. Atmospheric oxygen appears to be harmful during extended embryo culture. Embryo culture conditions might therefore be a potential risk factor for subsequent fetal development and the health of future children. No data are available concerning the obstetrics and neonatal outcomes after Day 3 transfer of embryos cultured under reduced and atmospheric oxygen tensions. A secondary analysis of a previous randomized controlled trial assessing clinical pregnancy outcomes was carried out. This analysis included 1125 consecutive oocyte donation cycles utilizing ICSI or IVF and Day 3 embryo transfers between November 2009 and April 2012. The whole cohort of donated oocytes from patients who agreed to participate in the study were randomly allocated (1:1 ratio) to a reduced O2 tension group (6% O2) or an air-exposed group (20% O2) based on a computer-generated randomization list. Fresh and vitrified oocytes were used for oocyte donation. Only those pregnancies with a live birth at or beyond 24 weeks of gestation were included. Day 3 embryos were cultured in an atmosphere of 5.5% CO2, 6% O2, 88.5% N2 versus a dual gas system in air. From the eligible 1125 cycles, 564 were allocated to the 6% O2 group and 561 cycles to the 20% O2 group. However, 50 and 62 cycles did not reach embryo transfer in the 6% and 20% O2 groups, respectively. No differences were found between 6% O2 and atmospheric O2 tension in the number of livebirths per embryo transfer (mean ± SD, 0.5 ± 0.7 versus 0.5 ± 0.7), pregnancy complications or neonatal outcomes. Both groups (6% and atmospheric O2) had similar single and twin delivery rates (40.8% versus 38.1% and 10.7% versus 12.3%, respectively). Preterm delivery rates and very preterm delivery rates (10.80% versus 13.24% and 1.25% versus 2.94%, respectively), birthweight (3229 ± 561 g versus 3154 ± 731 g), low birthweight (2.92% versus 2.45%), birth height (50.18 ± 2.41 cm versus 49.7 ± 3.59 cm), head circumference (34.16 ± 1.87 cm versus 33.09 ± 1.85 cm) and 1 min Apgar scores (8.96 ± 0.87 versus 8.89 ± 0.96) were also similar between 6% and atmospheric O2 groups, respectively. The number of liveborns finally analyzed is still small and not all obstetric and neonatal variables could be evaluated. Furthermore, a small proportion of the obstetric and neonatal data was obtained through a questionnaire filled out by the patients themselves. One reason for the lack of effect of oxygen concentration on pregnancy outcome could be the absence of trophectoderm cells at cleavage stage, which may make Day 3 embryos less susceptible to hypoxic conditions. Nowadays many IVF laboratories use a more physiological oxygen concentration for embryo culture. However, the benefits of using low oxygen concentration on both laboratory and clinical outcomes during embryo culture are still under debate. Furthermore, long-term studies investigating the effect of using atmospheric O2 are also needed. Gathering these type of clinical data is indeed, quite relevant from the safety perspective. The present data show that, at least in egg donation cycles undergoing Day 3 embryo transfers, culturing embryos under atmospheric oxygen concentration seems not to affect perinatal outcomes. The present project was supported by the R + D program of the Regional Valencian Government, Spain (IMPIVA IMDTF/2011/214). The authors declare that they have no conflict of interest with respect to the content of this manuscript. NCT01532193.

Evaluation of waterpipe smoke toxicity in C57BL/6 mice model

Waterpipe smoking is a popular pastime worldwide with statistics pointing to an alarming increase in consumption. In the current paper, the evaluation of sub-chronic waterpipe smoke exposure was undertaken using C57BL/6 female mice using a dynamic exposure setting to emulate smoke exposure. Mice were daily subjected to either one (single exposure, SE) or two sessions (double exposure, DE) of waterpipe-generated smoke (two-apple flavor) for a period of two months. Although lungs histopathological examination pointed to a minor inflammation in smoke-exposed mice compared to control air-exposed (CON) group, the lung weights of the waterpipe-exposed mice were significantly higher (+72% in SE and +39% in DE) (p < 0.01) when compared to CON group. Moreover, changes in the protein expression of several proteins such as iNOS and JNK were noted in the lungs of smoke-exposed mice. However, no changes in p38 and EGFR protein levels were noted between the three groups of mice. Our results mainly showed a significant increase in urea serum levels (+28%) in SE mice along with renal pathological damage in both SE and DE mice compared to CON. Additionally, severe significant DNA damages (p < 0.05) were reported in the lungs, kidneys, bone marrow and liver of waterpipe-exposed animals, using MTS and COMET assays. These findings highlighted the significant risks posed by sub-chronic waterpipe smoke exposure in the selected animal model and the pressing need for future better management of waterpipe indoor consumption.

Ameliorative Effect of Gum Acacia on Hookah Smoke-Induced Testicular Impairment in Mice.

We investigated some reproductive actions of hookah smoke (HS) exposure (30 min/day, for 30 days) in male mice, and the possible mitigative effect of the prebiotic agent gum acacia (GA) thereon. Control mice were air-exposed (AE). Twenty-four hours after the last exposure, the levels of some plasma reproductive hormones, biochemical markers of inflammation, oxidative and nitrosative stress and testicular histopathology were assessed. The urinary level of cotinine, a major nicotine metabolite, was also measured. HS exposure induced significant decreases in testosterone, estradiol, luteinizing hormone, and androgen binding protein, as well as glutathione reductase activity and levels of nitrite and total nitrite. Plasma inhibin B, alkaline phosphatase, lipopolysaccharide binding protein, uric acid, lactate dehydrogenase, lipid peroxidation, 8-oxo-2’-deoxyguanosine, and cytochrome C were significantly increased following HS exposure. In testicular homogenate, nuclear factor-κB (NF-ĸB), nuclear factor erythroid 2–related factor 2 (Nrf2), interleukin- 6 (IL-6), interleukin-1β (IL-1β), transforming growth factor-β1(TGF- β1), and tumor necrosis factor-α (TNF- α) were all significantly elevated, and the steroidogenic acute regulatory protein (StAR) significantly decreased. Histopathologically, there was slight impairment and disorganization of spermatogenesis. Urinary cotinine concentration was elevated significantly in the HS-exposed group compared with the air-exposed group. GA co-administration mitigated the adverse actions of HS measured. In conclusion, daily exposure to HS at the above dose induced adverse actions on the reproductive system of male mice. GA co-administration significantly mitigated these effects by reducing the inflammation, oxidative and nitrosative stress, via a mechanism involving Nrf2, and reduction of StAR expression.

In Utero Exposure to Second‐Hand Cigarette Smoke Promotes Epigenetically‐Mediated Cardiac Dysfunction in High‐Fat Fed Male Mice

We investigated whether in utero exposure to second‐hand cigarette smoke (SHS) would adversely affect cardiac structure/function in the exposed offspring fed a high‐fat diet. Pregnant mice (C57B1/6J) were exposed to SHS or air (4 hr/d) from gestational days 6–19. The male offspring (age: 65 days) from the SHS and air exposure groups were fed either normal chow, or high‐fat liquid diet (35% fat; HFD) for 16 weeks (n=12/group). Cardiac function was measured by echocardiography at baseline (30 days) and at the end of pair feeding. Mice were then sacrificed and heart tissue collected for histological and mRNAseq analysis. There was no significant difference in body weight or heart weigh/tibial length between the in utero SHS+HFD and in utero air+HFD treated offspring. However, compared to in utero air+HFD mice, in utero SHS+HFD mice had decreased left ventricular internal diameters and volumes during diastole (3.95±0.09 vs. 4.34±0.24 mm; 67.8±1.5 vs. 85.4±4.4 μl, P&lt;0.05) and systole (2.91±0.07 vs. 3.34±0.15 mm; 32.5±1.9 vs. 46.3±5.1 μl, P&lt;0.05), accompanied by increases in left ventricular wall thickness during diastole (0.72±0.03 vs. 0.66±0.03 mm, P&lt;0.01) and septal thickness during systole (1.2±0.06 vs. 0.99±0.05 mm, P&lt;0.05) and increased fractional shortening. There was also a significant increase in collagen in the hearts of the in utero SHS+HFD mice. These data are consistent with the development of concentric cardiac hypertrophy in in utero SHS+HFD mice. mRNAseq analysis of cardiac tissue revealed 100 up‐regulated and 120 down‐regulated genes in in utero air+HFD vs in utero SHS+HFD. Top Wiki Pathway terms included genes linked to adaptive cardiac hypertrophic responses: adrenergic receptor a1a, MAP2K1, MAP2K3, CDK7, CHUK, PDPK1 and IKBKE, microRNAs in cardiomyocytes, exercise induced changes in circadian rhythm (upregulated BMAL1, downregulated Per2) and signaling via estrogens, TNF alpha and MAP kinases. GO pathways identified included cardiac muscle contraction, protein acetylation and regulation of DNA methylation. We conclude that in utero exposure to SHS produces epigenetically‐regulated differential cardiac responses following challenge with obesogenic high fat diet. (NIH P20 GM103514).Support or Funding InformationNIH P20 GM103514