Inhibition of NADPH Oxidase-Derived Reactive Oxygen Species Decreases Expression of Inflammatory Cytokines in A549 Cells

The synergistic effects of citicoline and silymarin on liver injury and thyroid hormone disturbances in γ-irradiated rats

BACKGROUND

Exposure to ionizing radiation is inevitable due to its extensive use in industrial and medical applications. The search for effective and safe natural therapeutic agents as alternatives to chemical drugs is crucial to mitigate their side effects. This study aimed to evaluate the effects of citicoline as a standalone treatment or in combination with the anti-hepatotoxic drug silymarin in protecting against liver injury caused by γ-radiation in rats.

METHODS AND RESULTS

The rats were exposed to γ-radiation (7 Gy) and treated with citicoline (300 mg/kg/day) and/or silymarin (50 mg/kg/day). The results showed that citicoline alleviated liver damage in irradiated rats by reducing hepatic malondialdehyde levels, serum aspartate aminotransferase activity, and inflammatory mediators such as tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and nuclear factor-kappa B (NF-κB). It also increased acetylcholine (ACh) levels and the gene expression of the anti-inflammatory protein α7 nicotinic acetylcholine receptor (α7nAChR). Additionally, citicoline improved serum triiodothyronine (T3) levels, thyroid hormone receptor beta (TRβ) gene expression, and iodothyronine deiodinase type 1 activity in hepatic tissues of irradiated rats. Furthermore, citicoline enhanced the effects of silymarin on thyroxine (T4), TRβ, ACh, and α7nAChR when co-administered in irradiated rats. Histopathological analysis confirmed these findings, demonstrating improved liver tissue structure.

CONCLUSIONS

Citicoline mitigates γ-radiation-induced liver damage by reducing oxidative stress, activating the cholinergic anti-inflammatory pathway, and modulating thyroid hormone metabolism. These findings support the use of citicoline as a safe standalone treatment or as an adjuvant with silymarin for managing liver damage and thyroid hormone disturbances caused by γ-irradiation.

Paraprobiotic Levilactobacillus brevis KU15151 exhibits antioxidative and anti-inflammatory activities in LPS-induced A549 cells

Levilactobacillus brevis KU15151, isolated from kimchi, has been reported in previous studies to possess probiotic properties. Here, we sought to explore the potential of heat-killed L. brevis KU15151 in improving respiratory health by identifying its antioxidant and anti-inflammatory effects in LPS-induced A549 cells. Inactivated L. brevis KU15151 exhibited strong DPPH and ABTS radical-scavenging abilities (48.78 ± 3.95 % and 69.08 ± 1.09 %) and effectively reduced the production of reactive oxygen species (25.32 %). In addition, it was found to have anti-inflammatory effects by inhibiting phosphorylation of ERK 1/2 (0.556), JNK (0.476), p38 MAPK (0.580), p65 (0.579), and IκB-α (1.170), which are involved in MAPK and NF-κB signaling. It also suppressed the mRNA expression of pro-inflammatory cytokines (0.173-0.617), which are important factors in respiratory diseases. IL-6 (19.47 %) and eotaxin (50.19 %) levels were reduced as measured by ELISA. Therefore, heat-killed L. brevis KU15151 is expected to improve respiratory health.

Spatial and Temporal Distribution Characteristics and Cytotoxicity of Atmospheric PM2.5 in the Main Urban Area of Lanzhou City

PM2.5, as one of the most harmful pollutant in the atmospheric environment and population health, has received much attention. We monitored PM2.5 levels at five sampling sites in the Lanzhou City and collected PM2.5 particles from two representative sites for cytotoxicity experiment. The cytotoxicity of PM2.5 samples on A549 cells and migration ability of the cells were respectively detected by Cell Counting kit-8 (CCK-8) assay and scratch assay. We detected the levels of cellular inflammatory factors and oxidative damage-related biochemical indexes. RT-qPCR was used to detect the mRNA levels of NF-κB and epithelial-mesenchymal transition (EMT)-related genes. We found that the Lanlian Hotel station had the highest PM2.5 annual average concentration. The annual average concentration change curve of PM2.5 showed a roughly "U"-shaped distribution during the whole sampling period. The cytotoxicity experiment showed the viability of A549 cells decreased and the scratch healing rate increased in the 200 and 400 μg/mL PM2.5-treated groups. We also found 400 μg/mL PM2.5 induced changes in the mRNA levels of NF-κB and EMT-related genes, the mRNA levels of IKK-α, NIK, and NF-κB in the 400 μg/mL PM2.5 group were higher than those in the control group. The mRNA levels of E-cadherin decreased and α-SMA increased in the 400 μg/mL PM2.5 groups, and the mRNA levels of Fibronectin increased in the 400 μg/mL PM2.5 groups. Moreover, we found hydroxyl radical scavenging ability and T-AOC levels were lower, and LPO levels were higher in the 200 and 400 μg/mL PM2.5 groups, and the SOD activity of cells in the 400 µg/mL PM2.5 group decreased. And compared with the control group, the levels of TNF-α were higher in the 200 and 400 μg/mL PM2.5 groups and the levels of IL-1 were higher in the 400 μg/mL PM2.5 group. The results indicated that the cytotoxicity of atmospheric PM2.5 was related to oxidative damage, inflammatory response, NF-κB activity and EMT.

Revealing the mechanism and efficacy of natural products on treating the asthma: Current insights from traditional medicine to modern drug discovery

Asthma remains a significant global health challenge, demanding innovative approaches to treatment. Traditional medicine has a rich history of using natural products to alleviate asthmatic symptoms. However, transitioning from these traditional remedies to modern drug discovery approaches has provided fresh insights into the mechanisms and effectiveness of these natural products. This study provides our comprehensive review, which examines the current state of knowledge in the treatment of asthma. It delves into the mechanisms through which natural products ameliorate asthma symptoms, and it discusses their potential in the development of novel therapeutic interventions. Our analysis reveals that natural products, traditionally employed for asthma relief, exhibit diverse mechanisms of action. These include anti-inflammatory, bronchodilatory, immunomodulatory effects, and reducing gene expression. In the context of modern drug discovery, these natural compounds serve as valuable candidates for the development of novel asthma therapies. The transition from traditional remedies to modern drug discovery represents a promising avenue for asthma treatment. Our review highlights the substantial efficacy of natural products in managing asthma symptoms, underpinned by well-defined mechanisms of action. By bridging the gap between traditional and contemporary approaches, we contribute to the growing body of knowledge in the field, emphasizing the potential of natural products in shaping the future of asthma therapy.

Involvement of GPR43 Receptor in Effect of Lacticaseibacillus rhamnosus on Murine Steroid Resistant Chronic Obstructive Pulmonary Disease: Relevance to Pro-Inflammatory Mediators and Oxidative Stress in Human Macrophages

BACKGROUND

Cytokine storm and oxidative stress are present in chronic obstructive pulmonary disease (COPD). Individuals with COPD present high levels of NF-κB-associated cytokines and pro-oxidant agents as well as low levels of Nrf2-associated antioxidants. This condition creates a steroid-resistant inflammatory microenvironment. Lacticaseibacillus rhamnosus (Lr) is a known anti-cytokine in lung diseases; however, the effect of Lr on lung inflammation and oxidative stress in steroid-resistant COPD mice remains unknown.

OBJECTIVE

Thus, we investigated the Lr effect on lung inflammation and oxidative stress in mice and macrophages exposed to cigarette smoke extract (CSE) and unresponsive to steroids.

METHODS

Mice and macrophages received dexamethasone or GLPG-094 (a GPR43 inhibitor), and only the macrophages received butyrate (but), all treatments being given before CSE. Lung inflammation was evaluated from the leukocyte population, airway remodeling, cytokines, and NF-κB. Oxidative stress disturbance was measured from ROS, 8-isoprostane, NADPH oxidase, TBARS, SOD, catalase, HO-1, and Nrf2.

RESULTS

Lr attenuated cellularity, mucus, collagen, cytokines, ROS, 8-isoprostane, NADPH oxidase, and TBARS. Otherwise, SOD, catalase, HO-1, and Nrf2 were upregulated in Lr-treated COPD mice. Anti-cytokine and antioxidant effects of butyrate also occurred in CSE-exposed macrophages. GLPG-094 rendered Lr and butyrate less effective.

CONCLUSIONS

Lr attenuates lung inflammation and oxidative stress in COPD mice, suggesting the presence of a GPR43 receptor-dependent mechanism also found in macrophages.

New Data on Anti-Inflammatory and Wound Healing Potential of Transgenic Senna obtusifolia Hairy Roots: In Vitro Studies

Asthma is an inflammatory disease whose etiology remains unclear. Its characteristics encompass a wide range of clinical symptoms, inflammatory processes, and reactions to standard therapies. Plants produce a range of constitutive products and secondary metabolites that may have therapeutic abilities. The aim of this study was to determine the effects of Senna obtusifolia transgenic hairy root extracts on virus-induced airway remodeling conditions. Three cell lines were incubated with extracts from transformed (SOA4) and transgenic (SOPSS2, with overexpression of the gene encoding squalene synthase 1) hairy roots of Senna obtusifolia in cell lines undergoing human rhinovirus-16 (HRV-16) infection. The effects of the extracts on the inflammatory process were determined based on the expression of inflammatory cytokines (IL-8, TNF-α, IL-1α and IFN-γ) and total thiol content. The transgenic Senna obtusifolia root extract reduced virus-induced expression of TNF, IL-8 and IL-1 in WI-38 and NHBE cells. The SOPSS2 extract reduced IL-1 expression only in lung epithelial cells. Both tested extracts significantly increased the concentration of thiol groups in epithelial lung cells. In addition, the SOPPS2 hairy root extract yielded a positive result in the scratch test. SOA4 and SOPPS2 Senna obtusifolia hairy root extracts demonstrated anti-inflammatory effects or wound healing activity. The SOPSS2 extract had stronger biological properties, which may result from a higher content of bioactive secondary metabolites.

Hypoxia in Aging and Aging-Related Diseases: Mechanism and Therapeutic Strategies

As the global aging process continues to lengthen, aging-related diseases (e.g., chronic obstructive pulmonary disease (COPD), heart failure) continue to plague the elderly population. Aging is a complex biological process involving multiple tissues and organs and is involved in the development and progression of multiple aging-related diseases. At the same time, some of these aging-related diseases are often accompanied by hypoxia, chronic inflammation, oxidative stress, and the increased secretion of the senescence-associated secretory phenotype (SASP). Hypoxia seems to play an important role in the process of inflammation and aging, but is often neglected in advanced clinical research studies. Therefore, we have attempted to elucidate the role played by different degrees and types of hypoxia in aging and aging-related diseases and their possible pathways, and propose rational treatment options based on such mechanisms for reference.

The protective effects of apocynin in hyperoxic lung injury in neonatal rats

AIM

Inflammation and oxidate stress are significant factors in the pathogenesis of bronchopulmonary dysplasia (BPD). The aim of this study is to investigate the efficacy of apocynin (APO), an anti-inflammatory, antioxidant, and antiapoptotic drug, in the prophylaxis of neonatal hyperoxic lung injury.

METHOD

This experimental study included 40 neonatal rats divided into the control, APO, BPD, and BPD + APO groups. The control and APO groups were kept in a normal room environment, while the BPD and BPD + APO groups were kept in a hyperoxic environment. The rats in the APO and BPD + APO groups were administered intraperitoneal APO, while the control and BPD rats were administered ordinary saline. At the end of the trial, lung tissue was evaluated with respect to the degree of histopathological injury, apoptosis, oxidant and antioxidant capacity, and severity of inflammation.

RESULT

The BPD and BPD + APO groups exhibited higher mean histopathological injury and alveolar macrophage scores compared to the control and APO groups. Both scores were lower in the BPD + APO group in comparison to the BPD group. The BPD + APO group had a significantly lower average of TUNEL positive cells than the BPD group. The lung tissue examination indicated significantly higher levels of mean malondialdehyde (MDA), total oxidant status (TOS), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β) in the BPD group compared to the control and APO groups. While the TNF-α and IL-1β levels of the BPD + APO group were similar to that of the control group, the MDA and TOS levels were higher compared to the controls and lower compared to the BPD group. The BPD group demonstrated significantly lower levels/activities of mean total antioxidant status, glutathione reductase, superoxide dismutase, glutathione peroxidase in comparison to the control and APO groups. While the mean antioxidant enzyme activity of the BPD + APO group was lower than the control group, it was significantly higher compared to the BPD group.

CONCLUSION

This is the first study in the literature to reveal through an experimental neonatal hyperoxic lung injury that APO, an anti-inflammatory, antioxidant, and antiapoptotic drug, exhibits protective properties against the development of BPD.

Hepatoprotective effect of acetovanillone against methotrexate hepatotoxicity: Role of Keap-1/Nrf2/ARE, IL6/STAT-3, and NF-κB/AP-1 signaling pathways

This study targeted to examine the protective effects of acetovanillone (AV) against methotrexate (MTX)-induced hepatotoxicity. Thirty-two rats were allocated into four groups of eight animals; Group 1: Normal; Group 2: administered AV (100 ml/kg; P.O.) for 10 days; Group 3: challenged with MTX (20 mg/kg, i.p; single dose); Group 4: administered AV 5 days before and 5 days after MTX. For the first time, this study affords evidence for AV's hepatoprotective effects on MTX-induced hepatotoxicity. The underlined mechanisms behind its hepatic protection include counteracting MTX-induced oxidative injury via down-regulation of NADPH oxidase and up-regulation of Nrf2/ARE, SIRT1, PPARγ, and cytoglobin signals. Additionally, AV attenuated hepatic inflammation through down-regulation of IL-6/STAT-3 and NF-κB/AP-1 signaling. Network pharmacology analysis exhibited a high enrichment score between the interacting proteins and strongly suggested the intricate and essential role of the target proteins regulating MTX-induced oxidative damage and inflammatory perturbation. Besides, AV increased the in vitro cytotoxic activity of MTX toward PC-3, HeLa, and K562 cancer cell lines. On the whole, our investigation suggested that AV might be regarded as a promising adjuvant for the amelioration of MTX hepatotoxicity and/or increased its in vitro antitumor efficacy, and it could be used in patients receiving MTX.

Effect of Oxidative Stress on Diaphragm Dysfunction and Exercise Intervention in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) can cause extrapulmonary injury such as diaphragm dysfunction. Oxidative stress is one of the main factors causing diaphragm dysfunction in COPD. Exercise plays a positive role in the prevention and treatment of diaphragm dysfunction in COPD, and the changes in diaphragm structure and function induced by exercise are closely related to the regulation of oxidative stress. Therefore, on the basis of the review of oxidative stress and the changes in diaphragm structure and function in COPD, this article analyzed the effects of exercise on oxidative stress and diaphragm dysfunction in COPD and explored the possible mechanism by which exercise improves oxidative stress. Studies have found that diaphragm dysfunction in COPD includes the decline of muscle strength, endurance, and activity. Oxidative stress mainly affects the structure and function of the diaphragm in COPD through protein oxidation, protease activation and calcium sensitivity reduction. The effects of exercise on oxidative stress level and diaphragm dysfunction may differ depending on the intensity, duration, and style of exercise. The mechanism of exercise on oxidative stress in the diaphragm of COPD may include improving antioxidant capacity, reducing oxidase activity and improving mitochondrial function.

Advancing of Cellular Signaling Pathways in Respiratory Diseases Using Nanocarrier Based Drug Delivery Systems

Cell Signaling pathways form an integral part of our existence that allows the cells to comprehend a stimulus and respond back. Such reactions to external cues from the environment are required and are essential to regulate the normal functioning of our body. Abnormalities in the system arise when there are errors developed in these signals, resulting in a complication or a disease. Presently, respiratory diseases contribute to being the third leading cause of morbidity worldwide. According to the current statistics, over 339 million people are asthmatic, 65 million are suffering from COPD, 2.3 million are lung cancer patients and 10 million are tuberculosis patients. This toll of statistics with chronic respiratory diseases leaves a heavy burden on society and the nation's annual health expenditure. Hence, a better understanding of the processes governing these cellular pathways will enable us to treat and manage these deadly respiratory diseases effectively. Moreover, it is important to comprehend the synergy and interplay of the cellular signaling pathways in respiratory diseases, which will enable us to explore and develop suitable strategies for targeted drug delivery. This review, in particular, focuses on the major respiratory diseases and further provides an in-depth discussion on the various cell signaling pathways that are involved in the pathophysiology of respiratory diseases. Moreover, the review also analyses the defining concepts about advanced nano-drug delivery systems involving various nanocarriers and propose newer prospects to minimize the current challenges faced by researchers and formulation scientists.

Reactive oxygen species modulators in pulmonary medicine

Adapted to effectively capture oxygen from inhaled air and deliver it to all other parts of the body, the lungs constitute the organ with the largest surface area. This makes the lungs more susceptible to airborne pathogens and pollutants that mediate pathologies through generation of reactive oxygen species (ROS). One pathological consequence of excessive levels of ROS production is pulmonary diseases that account for a large number of mortality and morbidity in the world. Of the various mechanisms involved in pulmonary disease pathogenesis, mitochondrial dysfunction takes prominent importance. Herein, we briefly describe the significance of oxidative stress caused by ROS in pulmonary diseases and some possible therapeutic strategies.

Neuroinflammation, oxidative stress and their interplay in neuropathic pain: Focus on specialized pro-resolving mediators and NADPH oxidase inhibitors as potential therapeutic strategies

Neuropathic pain (NP) is a chronic condition that results from a lesion or disease of the nervous system, greatly impacting patients' quality of life. Current pharmacotherapy options deliver inadequate and/or insufficient responses and thus a significant unmet clinical need remains for alternative treatments in NP. Neuroinflammation, oxidative stress and their reciprocal relationship are critically involved in NP pathophysiology. In this context, new pharmacological approaches, aiming at enhancing the resolution phase of inflammation and/or restoring redox balance by targeting specific reactive oxygen species (ROS) sources, are emerging as potential therapeutic strategies for NP, with improved efficacy and safety profiles. Several reports have demonstrated that administration of exogenous specialized pro-resolving mediators (SPMs) ameliorates NP pathophysiology. Likewise, deletion or inhibition of the ROS-generating enzyme NADPH oxidase (NOX), particularly its isoforms 2 and 4, results in beneficial effects in NP models. Notably, SPMs also modulate oxidative stress and NOX also regulates neuroinflammation. By targeting neuroinflammatory and oxidative pathways, both SPMs analogues and isoform-specific NOX inhibitors are promising therapeutic strategies for NP.

Assessment of acute and repeated pulmonary toxicities of oligo(2-(2-ethoxy)ethoxyethyl guanidium chloride in mice

Oligo(2-(2-ethoxy)ethoxyethyl guanidinium chloride (PGH) and polyhexamethyleneguanidine phosphate (PHMG-P) are cationic biocides containing a guanidine group. Direct exposure of the lungs to PHMG-P is known to induce pulmonary inflammation and fibrotic changes. Few studies have assessed the pulmonary toxicity of PGH, another member of the guanidine family. In this study, we assessed the acute and repeated toxicity of PGH and PHMG-P to compare the pathological progression induced by both chemicals. PGH (1.5 mg/kg) or PHMG (0.6 mg/kg) was instilled intratracheally to mice once or three times every 4 days; subsequently, cytokine levels were quantified and a histopathological examination was performed. To verify the toxic mechanism of PGH, we quantified cell viability and cytokine production induced by PGH or PHMG-P in the presence or absence of anionic material in cells. Instillation of PGH and PHMG-P into the mouse lung increased cytokine production, immune cell infiltration, and pulmonary fibrotic changes. These pathological changes were exacerbated over time in the single- and the repeated-dose PHMG-P groups, but were resolved over time in the PGH groups. PGH or PHMG-P showed cytotoxic effects, IL-1β secretion, and ROS production in a dose-dependent manner in human cell lines. However, the co-treatment of anionic materials with PGH or PHMG-P significantly reduced these toxic responses, which confirmed that the cation of PGH disrupted the plasma membrane via ionic interaction, as observed for PHMG-P. In addition, we suggest the disruption of plasma membrane as a molecular initiating event of cationic chemicals-induced adverse outcomes when exposed directly to the lungs.