Effect of fluticasone propionate on human nasal fibroblasts exposed to urban particulate matter

PM2.5 Induces Pyroptosis via Activation of the ROS/NF-κB Signaling Pathway in Bronchial Epithelial Cells

Background and Objectives: Fine particulate matter, PM2.5, is becoming a major threat to human health, particularly in terms of respiratory diseases. Pyroptosis is a recently discovered and distinct form of cell death, characterized by pore formation in the cell membrane and secretions of proinflammatory cytokines. There has been little research on the effect of PM2.5 on pyroptosis, especially in airway epithelium. We investigated whether PM2.5-related oxidative stress induces pyroptosis in bronchial epithelial cells and defined the underlying mechanisms. Materials and Methods: After exposure of a BEAS-2B cell line to PM2.5 concentration of 20 µg/mL, reactive oxygen species (ROS) levels, parameters related to pyroptosis, and NF-κB signaling were measured by Western blotting, immunofluorescence, and ELISA (Enzyme-linked immunosorbent assay). Results: PM2.5 induced pyroptotic cell death, accompanied by LDH (Lactate dehydrogenase) release and increased uptake of propidium iodide in a dose-dependent manner. PM2.5 activated the NLRP3-casp1-gasdermin D pathway, with resulting secretions of the proinflammatory cytokines IL-1β and IL-18. The pyroptosis activated by PM2.5 was alleviated significantly by NLRP3 inhibitor. In PM2.5-exposed BEAS-2B cells, levels of intracellular ROS and NF-κB p65 increased. ROS scavenger inhibited the expression of the NLRP3 inflammasome, and the NF-κB inhibitor attenuated pyroptotic cell death triggered by PM2.5 exposure, indicating that the ROS/NF-κB pathway is involved in PM2.5-induced pyroptosis. Conclusions: These findings show that PM2.5 exposure can cause cell injury by NLRP3-inflammasome-mediated pyroptosis by upregulating the ROS/NF-κB pathway in airway epithelium.

The role of cytokines/chemokines in an aging skin immune microenvironment

Reversing or slowing down the skin aging process is one of the most intriguing areas of focus across the social and scientific communities around the world. While aging is considered a universal and inevitable natural process of physiological decline, the aging of the skin is the most apparent visual representation of an individual's health. Aging skin may be objectively defined by epidermal thinning; increased transepidermal water loss; decreased cutaneous barrier function; loss of elasticity, laxity, and textured appearance; and gradual deterioration of the epidermal immune environment. As the largest structure of the immune system and of the body as a whole, the skin is the most vulnerable barrier of defense against the environment. The skin reflects an individual's exposures, lifestyle habits, and overall health. From an immunological perspective, cytokines and chemokines act as a central character in the communicating of the immunity in skin aging. These cell signaling proteins serve as the intercellular communication link. This review aims to elucidate how cell-cell crosstalk through cytokines and chemokines, and the interplay between host cells, infiltrating immune cells, and exogenous factors contribute to the overall aging skin.

Effect of MP-AzeFlu compared to monotherapy on COX-2, PGE2 , and EP2 gene expression in upper airway mucosa

MP-AzeFlu (intranasal fluticasone and azelastine) has been widely studied and has demonstrated efficacy in Allergic rhinitis with a superior effect compared to these drugs administered individually; however, the mechanism by which MP-AzeFlu produces this improved clinical effect has not yet been fully explained. In this study, we investigated the effect of MP-AzeFlu and fluticasone propionate (FP) on arachidonic acid metabolism as measured by changes in regulation of cyclooxygenase (COX) isoforms, prostaglandin (PG) D2 , PGE2 , PGE2 receptor (EP) 2, and EP3. Expression of these key inflammation markers was assessed through an in vitro model of upper airway inflammation using fibroblasts derived from both healthy and inflamed upper airway mucosa. Both MP-AzeFlu and FP inhibited interleukin-1β-induced COX-2 messenger RNA (mRNA) and protein expression and PGE2 secretion in vitro. MP-AzeFlu and FP both upregulated EP2 mRNA expression, though neither upregulated EP2 protein expression. This downregulation of COX-2 and PGE2 coupled with upregulation of EP2 receptor expression reinforces the anti-inflammatory effect of MP-AzeFlu in upper airway inflammation.

Effect of Ethyl Acetate Fraction from Eucommia ulmoides Leaves on PM2.5-Induced Inflammation and Cognitive Dysfunction

This study aimed to evaluate the protective effect of the ethyl acetate from Eucommia ulmoides leaves (EFEL) on PM2.5-induced cognitive impairment in BALB/c mice. EFEL improved PM2.5-induced cognitive decline by improving spontaneous alternative behavioral and long-term memory ability. EFEL increased ferric reducing activity power (FRAP) in serum. In addition, EFEL increased superoxide dismutase (SOD) and reduced glutathione (GSH) contents and inhibited the production of malondialdehyde (MDA) in lung and brain tissues. EFEL also restored the mitochondrial function by regulating reactive oxygen species (ROS) production, mitochondrial membrane potential (MMP) level, and ATP level in lung and brain tissues. EFEL ameliorated the cholinergic system by regulating the acetylcholine (ACh) content and acetylcholinesterase (AChE) activity in the brain tissue and the expression of AChE and choline acetyltransferase (ChAT) in the whole brain and hippocampal tissues. EFEL reduced PM2.5-induced excessive expression of inflammatory protein related to the lung, whole brain, olfactory bulb, and hippocampus. Physiological compounds of EFEL were identified as 5-O-caffeolyquinic acid, rutin, quercetin, and quercetin glycosides. As a result, EFEL has anti-inflammation and anti-amnesic effect on PM2.5-induced cognitive impairment by regulating the inflammation and inhibiting the lung and brain tissue dysfunction, and its effect is considered to be due to the physiological compounds of EFEL.

Eupatilin Inhibits Reactive Oxygen Species Generation via Akt/NF-κB/MAPK Signaling Pathways in Particulate Matter-Exposed Human Bronchial Epithelial Cells

Background: Eupatilin is an active flavon extracted from the Artemisia species and has properties such as antioxidant, anti-inflammatory, and anti-cancer. We examined the effect of eupatilin using fine particulate matter (FPM) and human bronchial epithelial cell line (BEAS-2B) to confirm the potential of eupatilin as a therapeutic agent for respiratory diseases caused by FPM. Methods: Reactive oxygen species (ROS) levels were checked by flow cytometry to identify if FPM and eupatilin affect ROS production. Western blotting was performed to identify the mechanism of action of eupatilin in FPM-exposed BEAS-2B cells. Results: When cells were exposed to FPM above 12.5 μg/mL concentration for 24 h, ROS production increased significantly compared to the control. When eupatilin was added to cells exposed to FPM, the ROS level decreased proportionally with the eupatilin dose. The phosphorylation of Akt, NF-κB p65, and p38 MAPK induced by FPM was significantly reduced by eupatilin, respectively. Conclusion: FPM cause respiratory disease by producing ROS in bronchial epithelial cells. Eupatilin has been shown to inhibit ROS production through altering signaling pathways. The ROS inhibiting property of eupatilin can be exploited in FPM induced respiratory disorders.