Chronic and Binge Alcohol Ingestion Increases Truncated Oxidized Phosphatidylcholines in Mice Lungs Due to Increased Oxidative Stress

Oxidative balance score and its association with chronic inflammatory airway diseases and mortality: a population-based study

Objective

The aim of this research was to explore the possible connection between combined Oxidative Balance Score (OBS) and the prevalence of chronic inflammatory airway diseases (CIAD), including asthma, chronic obstructive pulmonary disease (COPD), and chronic bronchitis, along with the mortality rate among individuals with CIAD.

Methods

Data were gathered from the National Health and Nutrition Examination Survey (NHANES) 2013-2018 cycles. The Oxidative Balance Score (OBS) was calculated using 16 different nutrients and 4 different lifestyles, which was then categorized into four groups. The CIAD included individuals with self-reported asthma, chronic bronchitis, or COPD. Mortality data up to December 31, 2019, was obtained from the National Death Index. In cross-sectional studies, the association between OBS and the prevalence of total and specific CIAD was examined using multiple logistic regressions. Dose-response relationships were analyzed through restricted cubic spline regression (RCS). In prospective cohort studies, cumulative survival rates were determined using the Kaplan-Meier method and compared with log-rank tests. Multiple COX regressions were conducted to evaluate the relationship between OBS and all-cause as well as respiratory diseases mortality among participants with CIAD.

Results

A total of 12,458 adults were enrolled in this study. The demographic characteristics of the study population revealed a mean age of 52.25 ± 15.8 years, 47.73% being male, and the majority identified as Non-Hispanic White (66.87%). We found that 20.26% of the participants were suffered from CIAD, followed by asthma (15.41%), chronic bronchitis (6.10%) and COPD (3.80%), respectively. The median OBS levels were 20.98 with a standard deviation of 0.17. After adjusting for all confounders, we found that the highest quartile of OBS was significantly associated with lower prevalence of total CIAD (OR = 0.71, 95% CI 0.64-0.81), asthma (OR = 0.62, 95% CI 0.52-0.73), chronic bronchitis (OR = 0.64, 95% CI 0.44-0.92), and COPD (OR = 0.48, 95% CI 0.31-0.77) compared to the lowest quartile. Additionally, a linear and inverse relationship was found between OBS and the incidence of various respiratory disorders. Kaplan-Meier survival analysis showed that individuals in the highest quartile of OBS had the lowest risk of both all-cause mortality (log-rank test p = 0.017) and respiratory diseases mortality (log-rank test p < 0.001). Furthermore, after adjusting for multiple factors, individuals in the fourth quartile continued to show a significantly reduced risk of all-cause mortality (HR = 0.71, 95% CI 0.55-0.93) and respiratory diseases mortality (HR = 0.53, 95% CI 0.43-0.74) in comparison to those in the lowest quartile of OBS levels.

Conclusion

The findings revealed that a higher OBS was significantly linked to a decreased prevalence of total and specific CIAD, including asthma, chronic bronchitis, and COPD. Higher OBS levels were also associated with reduced mortality from both all causes and respiratory diseases among CIAD patients. These findings offer valuable information on the role of diet and lifestyle in preventing CIAD.

Association between oxidative balance score and chronic obstructive pulmonary disease: A cross-sectional study

Oxidative stress is an essential contributor to the progression of chronic obstructive pulmonary disease (COPD). A systematic assessment of diet patterns and lifestyle with the oxidative balance score (OBS) to reflect oxidative stress levels will help predict the risk of COPD. This study conducted a cross-sectional analysis to assess the link between OBS and COPD. 5162 participants were collected from 2013 to 2018 from the National Health and Nutrition Examination Survey (NHANES). Multivariate logistic regression models were applied to assess the relationship between OBS and COPD prevalence. The linearity of the association was explored using smoothed curve fitting. In addition, further subgroup analysis and interaction tests were conducted to ascertain the consistency of the relationship across diverse populations. Results of the multivariate logistic regression models indicated a negative association between OBS and the odds of COPD prevalence. Each incremental unit in OBS correlated with a 3% reduction in the odds of COPD in the fully adjusted model (OR 0.97, 95% CI 0.95-0.99). Further analysis by OBS tertiles indicated that individuals in the highest OBS tertile (T3) had a 17% lower probability of COPD compared to those in the lowest tertile (T1) in the fully adjusted model (OR 0.83, 95% CI 0.64-0.97). The smoothed curve fitting supported the negative association between OBS and COPD. Subgroup analyses revealed that the protective effect of OBS was notably pronounced among the non-hypertensive and non-diabetic populations. These findings suggest a negative link between OBS and COPD, underscoring the importance of antioxidant-rich diets and lifestyles in preventing COPD.

Evaluation of the Therapeutic Potential of Sulfonyl Urea Derivatives as Soluble Epoxide Hydrolase (sEH) Inhibitors

The inhibition of soluble epoxide hydrolase (sEH) can reduce the level of dihydroxyeicosatrienoic acids (DHETs) effectively maintaining endogenous epoxyeicosatrienoic acids (EETs) levels, resulting in the amelioration of inflammation and pain. Consequently, the development of sEH inhibitors has been a prominent research area for over two decades. In the present study, we synthesized and evaluated sulfonyl urea derivatives for their potential to inhibit sEH. These compounds underwent extensive in vitro investigation, revealing their potency against human and mouse sEH, with 4f showing the most promising sEH inhibitory potential. When subjected to lipopolysaccharide (LPS)-induced acute lung injury (ALI) in studies in mice, compound 4f manifested promising anti-inflammatory efficacy. We investigated the analgesic efficacy of sEH inhibitor 4f in a murine pain model of tail-flick reflex. These results validate the role of sEH inhibition in inflammatory diseases and pave the way for the rational design and optimization of sEH inhibitors based on a sulfonyl urea template.

Oxidized phospholipid-protein adducts: The future targets of interest

Phospholipids are key biomolecules with important roles as components of membranes, lipoproteins and as signalling molecules. However, phospholipids are quite prone to oxidation. Upon oxidation they generate several types of oxidation products including long chain oxidation products, as hydroperoxyl and hydroxy derivatives, and highly reactive oxidation products, like small aldehydes and truncated oxidized phospholipids. The formation of protein adducts with small electrophilic aldehydes (like malondialdehyde) is now well studied, however, the aggregation of proteins with truncated oxidized phospholipids lacks research. This paper provides a short overview of the formation of protein adducts with truncated oxidized phospholipids as well as a gathering of the research on this topic. The literature found reports the synthesis, detection and fragmentation of this type of adducts, mainly focusing on truncated oxidized phospholipid' products from phosphatidylcholine class and few peptides and proteins, as human serum albumin and Apo B100, leaving unattended the screening in vivo and in disease correlation, thus lacking possible association with their biological role. These adducts are a consequence of oxidative modifications to important biomolecules and their involvement in the organism is still unclear, revealing the urgent need for more investigation in this area.

Alcohol and e-cigarette damage alveolar-epithelial barrier by activation of P2X7r and provoke brain endothelial injury via extracellular vesicles

BACKGROUND

Use of nicotine containing products like electronic cigarettes (e-Cig) and alcohol are associated with mitochondrial membrane depolarization, resulting in the extracellular release of ATP, and mitochondrial DNA (mtDNA), mediating inflammatory responses. While nicotine effects on lungs is well-known, chronic alcohol (ETH) exposure also weakens lung immune responses and cause inflammation. Extracellular ATP (eATP) released by inflammatory/stressed cells stimulate purinergic P2X7 receptors (P2X7r) activation in adjacent cells. We hypothesized that injury caused by alcohol and e-Cig to pulmonary alveolar epithelial cells (hPAEpiC) promote the release of eATP, mtDNA and P2X7r in circulation. This induces a paracrine signaling communication either directly or via EVs to affect brain cells (human brain endothelial cells - hBMVEC).

METHODS

We used a model of primary human pulmonary alveolar epithelial cells (hPAEpiC) and exposed the cells to 100 mM ethanol (ETH), 100 µM acetaldehyde (ALD), or e-Cig (1.75 µg/mL of 1.8% or 0% nicotine) conditioned media, and measured the mitochondrial efficiency using Agilent Seahorse machine. Gene expression was measured by Taqman RT-qPCR and digital PCR. hPAEpiC-EVs were extracted from culture supernatant and characterized by flow cytometric analysis. Calcium (Ca2+) and eATP levels were quantified using commercial kits. To study intercellular communication via paracrine signaling or by EVs, we stimulated hBMVECs with hPAEpiC cell culture medium conditioned with ETH, ALD or e-cig or hPAEpiC-EVs and measured Ca2+ levels.

RESULTS

ETH, ALD, or e-Cig (1.8% nicotine) stimulation depleted the mitochondrial spare respiration capacity in hPAEpiC. We observed increased expression of P2X7r and TRPV1 genes (3-6-fold) and increased intracellular Ca2+ accumulation (20-30-fold increase) in hPAEpiC, resulting in greater expression of endoplasmic reticulum (ER) stress markers. hPAEpiC stimulated by ETH, ALD, and e-Cig conditioned media shed more EVs with larger particle sizes, carrying higher amounts of eATP and mtDNA. ETH, ALD and e-Cig (1.8% nicotine) exposure also increased the P2X7r shedding in media and via EVs. hPAEpiC-EVs carrying P2X7r and eATP cargo triggered paracrine signaling in human brain microvascular endothelial cells (BMVECs) and increased Ca2+ levels. P2X7r inhibition by A804598 compound normalized mitochondrial spare respiration, reduced ER stress and diminished EV release, thus protecting the BBB function.

CONCLUSION

Abusive drugs like ETH and e-Cig promote mitochondrial and endoplasmic reticulum stress in hPAEpiC and disrupts the cell functions via P2X7 receptor signaling. EVs released by lung epithelial cells against ETH/e-cig insults, carry a cargo of secondary messengers that stimulate brain cells via paracrine signals.

Alcohol and e-cigarette damage alveolar-epithelial barrier by activation of P2X7r and provoke brain endothelial injury via extracellular vesicles

Background

Use of nicotine containing products like electronic cigarettes (e-Cig) and alcohol are associated with mitochondrial membrane depolarization, resulting in the extracellular release of ATP, and mitochondrial DNA (mtDNA), mediating inflammatory responses. While nicotine effects on lungs is well-known, chronic alcohol (ETH) exposure also weakens lung immune responses and cause inflammation. Extracellular ATP (eATP) released by inflammatory/stressed cells stimulate purinergic P2X7 receptors (P2X7r) activation in adjacent cells. We hypothesized that injury caused by alcohol and e-Cig to pulmonary alveolar epithelial cells (hPAEpiC) promote the release of eATP, mtDNA and P2X7r in circulation. This induces a paracrine signaling communication either directly or via EVs to affect brain cells (human brain endothelial cells - hBMVEC).

Methods

We used a model of primary human pulmonary alveolar epithelial cells (hPAEpiC) and exposed the cells to 100 mM ethanol (ETH), 100 μM acetaldehyde (ALD), or e-Cig (1.75μg/mL of 1.8% or 0% nicotine) conditioned media, and measured the mitochondrial efficiency using Agilent Seahorse machine. Gene expression was measured by Taqman RT-qPCR and digital PCR. hPAEpiC-EVs were extracted from culture supernatant and characterized by flow cytometric analysis. Calcium (Ca2+) and eATP levels were quantified using commercial kits. To study intercellular communication via paracrine signaling or by EVs, we stimulated hBMVECs with hPAEpiC cell culture medium conditioned with ETH, ALD or e-cig or hPAEpiC-EVs and measured Ca2+ levels.

Results

ETH, ALD, or e-Cig (1.8% nicotine) stimulation depleted the mitochondrial spare respiration capacity in hPAEpiC. We observed increased expression of P2X7r and TRPV1 genes (3-6-fold) and increased intracellular Ca2+ accumulation (20-30-fold increase) in hPAEpiC, resulting in greater expression of endoplasmic reticulum (ER) stress markers. hPAEpiC stimulated by ETH, ALD, and e-Cig conditioned media shed more EVs with larger particle sizes, carrying higher amounts of eATP and mtDNA. ETH, ALD and e-Cig (1.8% nicotine) exposure also increased the P2X7r shedding in media and via EVs. hPAEpiC-EVs carrying P2X7r and eATP cargo triggered paracrine signaling in human brain microvascular endothelial cells (BMVECs) and increased Ca2+ levels. P2X7r inhibition by A804598 compound normalized mitochondrial spare respiration, reduced ER stress and diminished EV release, thus protecting the BBB function.

Conclusion

Abusive drugs like ETH and e-Cig promote mitochondrial and endoplasmic reticulum stress in hPAEpiC and disrupts the cell functions via P2X7 receptor signaling. EVs released by lung epithelial cells against ETH/e-cig insults, carry a cargo of secondary messengers that stimulate brain cells via paracrine signals.