Emodin alleviates alternatively activated macrophage and asthmatic airway inflammation in a murine asthma model

Abstract

Alternatively activated macrophages (AAMs) are not only associated with asthma but also lead to asthmatic airway inflammation and remodeling. Inhibition of AAMs is an alternative therapeutic strategy for treating asthma. In this study we investigated whether emodin (1,3,8-trihydroxy-6-methylanthraquinone), isolated from the rhizome of Rheum palmatum, alleviated asthmatic airway inflammation and reduced AAM polarization in a murine asthma model. Mice were sensitized with a triple allergen mix containing dust mite, ragweed and aspergillus (DRA). In mice with DRA-induced asthma, asthmatic inflammation was significantly enhanced. Intraperitoneal injection of emodin (20 mg·kg·d, ip) 1 h prior to DRA challenge on days 12-14 significantly decreased pulmonary eosinophil and lymphocyte infiltration, mucus secretion and serum IgE production, as well as IL-4 and IL-5 production in bronchoalveolar lavage fluid. In response to emodin treatment, activated markers of AAM Ym-1, Fizz-1 and arginase-1 in the lung tissues were remarkably decreased. In mouse bone marrow-derived macrophages (BMDMs) in vitro, emodin (2-50 μmol/L) dose-dependently inhibited IL-4-induced AAM polarization and STAT6 phosphorylation. Collectively, our results suggest that emodin effectively ameliorates asthmatic airway inflammation and AAM polarization, and it may therefore become a potential agent for the treatment of asthma.

Rhubarb alleviates acute lung injury by modulating gut microbiota dysbiosis in mice

“…Scientists have explored the differences in structure and abundance of the intestinal micro ora under healthy and disease conditions to identify the role of the gut microbiota during disease development. Dysbiosis in the gut micro ora also occurs in many disorders [15][16][17]. ALI activated the systemic in ammatory response and secretion of in ammatory mediators, leading to intestinal mucosal barrier damage and intestinal bacterial translocation, which affected the intestinal ora diversity, distribution and composition.…”

“…Therefore, rhubarb regulated the gut microbiota and protected against ALI. Emodin, extracted from rhubarb, has shown anti-in ammatory properties for treating pancreatitis, atherosclerosis, asthma, and ALI [15][16][17]. Xiao et al indicated that emodin relieved pulmonary edema and MCP-1 and E-selectin secretions and inhibited LPS-induced pulmonary damage [17].…”

Physalis peruviana L. inhibits ovalbumin‑induced airway inflammation by attenuating the activation of NF‑κB and inflammatory molecules

“…Macrophage activation is not only associated with the airway inflammatory response but also with airway remodeling ( 39 ), and cell-derived MCP-1 acts as a potent eosinophil chemoattractant ( 40 , 41 ). Therefore, the regulation of macrophage activation and overproduction of MCP-1 is an alternative therapeutic strategy for treating allergic asthma.…”

Heterogeneous macrophages: Supersensors of exogenous inducing factors

“…Aloe vera extract can downregulate TNF‐α, IL‐1β and IL‐6 expression in macrophages in a mouse model of lipopolysaccharide (LPS)‐induced acute lung injury (ALI), thus potentially protecting LPS‐induced ALI . Other extracts used in traditional Chinese medicine, such as curcumin, emodin, berberine and grass coumarone, have similar effects. Most of the traditional Chinese medications that inhibit tumours have “promoting blood stasis, reducing swelling and dispersing” effects.…”