Astragalus mongholicus Bunge Water Extract Exhibits Anti-inflammatory Effects in Human Neutrophils and Alleviates Imiquimod-Induced Psoriasis-Like Skin Inflammation in Mice

Abstract

Neutrophils are the primary immune cells in innate immunity, which are related to various inflammatory diseases. Astragalus mongholicus Bunge is a Chinese medicinal herb used to treat various oxidative stress-related inflammatory diseases. However, there are limited studies that elucidate the effects of Astragalus mongholicus Bunge in human neutrophils. In this study, we used isolated human neutrophils activated by various stimulants to investigate the anti-inflammatory effects of Astragalus mongholicus Bunge water extract (AWE). Cell-free assays were used to examine free radicals scavenging capabilities on superoxide anion, reactive oxygen species (ROS), and nitrogen-centered radicals. Imiquimod (IMQ) induced psoriasis-like skin inflammation mouse model was used for investigating anti-psoriatic effects. We found that AWE inhibited superoxide anion production, ROS generation, and elastase release in human neutrophils, which exhibiting a direct anti-neutrophil effect. Moreover, AWE exerted a ROS scavenging ability in the 2,2’-Azobis (2-amidinopropane) dihydrochloride assay, but not superoxide anion in the xanthine/xanthine oxidase assay, suggesting that AWE exhibited anti-oxidation and anti-inflammatory capabilities by both scavenging ROS and by directly inhibiting neutrophil activation. AWE also reduced CD11b expression and adhesion to endothelial cells in activated human neutrophils. Meanwhile, in mice with psoriasis-like skin inflammation, administration of topical AWE reduced both the affected area and the severity index score. It inhibited neutrophil infiltration, myeloperoxidase release, ROS-induced damage, and skin proliferation. In summary, AWE exhibited direct anti-inflammatory effects by inhibiting neutrophil activation and anti-psoriatic effects in mice with IMQ-induced psoriasis-like skin inflammation. Therefore, AWE could potentially be a pharmaceutical Chinese herbal medicine to inhibit neutrophilic inflammation for anti-psoriasis.

A double-edged sword: ROS related therapies in the treatment of psoriasis

“… [62] Astragalus mongholicus bunge water extract human neutrophils &IMQ-induced Ps mice Transdermal Topical application can effectively remove ROS and inhibit neutrophil activation. [60] Ambroxol IMQ-induced Ps mice Subcutaneous & Transdermal High safety profile and exhibits excellent antioxidant as well as anti-inflammatory properties [61] Nano formulations Nano particles Cur PLGA IMQ-induced Ps mice Transdermal Encapsulation of Cur into PLGA enhances the biological activity of Cur by enhancing drug penetration, release and dispersion [67] VES-g-ε-PLL& silk fibroin This nano formulation exhibits enhanced skin penetration and a more effective anti-keratinization process. [68] Bilirubin IMQ-induced Ps mice Transdermal BRNPs caused little toxicity and high biocompatibility.…”

“…Benefiting from less trauma, most liquid formulations tend to choose transdermal delivery. Recent studies point out that smear Kan-Lu-Hsiao-Tu-Tan (KLHTT, a traditional Chinese medicine formula) [59] , astragalus mongholicus bunge water extrat [60] , ambroxol [61] or perillyl alcohol [62] at the affected area of imiquimod (IMQ) -induced Ps mice effectively reduce the skin lesions. KLHTT and astragalus mongholicus bunge water extract decrease ROS generation by inhibiting the respiratory burst of neutrophils [ 59 , 60 ].…”

Molybdenum Nanoparticles Ameliorate Psoriatic Lesions by Inhibiting the ROS/NF-κb Signaling Axis

“…Therefore, direct antioxidant enzyme supplementation is not recommended. Scientists have explored numerous traditional herbal medicines or their extracts that can reduce the generation of ROS in keratinocytes through systemic or local administration. − However, these drugs may have irritant or even toxic effects on the skin coupled with poor stability, which limits their application. Hence, there is an urgent need to develop novel antioxidant formulations.…”

Study on the Biotransformation and Activities of Astragalosides from Astragali Radix In Vitro and In Vivo

“…Many studies have reported the following activities of AR: antioxidant effects, , anti-inflammatory effects, − immunoregulatory effects, anticancer effects, antiviral effects, hepatoprotective effects, hypoglycemic effects, potent cardiovascular protective effects, and ability to ameliorate peritoneal fibrosis . These pharmacological effects are associated with the diversity of their components, including astragalosides (AGs), isoflavonoids, polysaccharides, amino acids, and various trace elements.…”