Salidroside suppresses group 2 innate lymphoid cell-mediated allergic airway inflammation by targeting IL-33/ST2 axis.

Salidroside, an active component extracted from Rhodiola rosea, has been reported to inhibit allergic asthma. However, its mechanism has not been fully elucidated. Group 2 innate lymphoid cells (ILC2s) accumulate in the lung and cooperate with other cells to drive type 2 inflammation stimulated by inhaled allergens. The study aims to explore the suppressive effect of salidroside on ILC2s and IL-33/IL-33R (ST2) axis in allergic airway inflammation. The ovalbumin (OVA)-sensitized/challenged mice were established. Airway eosinophil recruitment, increased total IgE in the serum and type 2 cytokines IL-4, IL-5, and IL-13 in the bronchoalveolar lavage fluids and lung tissues were identified in the OVA-induced mice model, all of which were inhibited by pretreatment with different doses of salidroside. Moreover, salidroside suppressed lung total ILC2 and ST2-expressing ILC2 accumulation, lung IL-33 and ST2 expressions in mice. In vitro, OVA could induce IL-33 expression in BEAS-2B cells, which was also effectively inhibited by salidroside. This study firstly reveals salidroside as a potential therapeutic drug for allergic asthma by inhibiting ILC2-mediated airway inflammation via targeting IL-33/ST2 axis.

Administration of Rhodiola kirilowii Extracts during Mouse Pregnancy and Lactation Stimulates Innate but Not Adaptive Immunity of the Offspring.

The use of antibiotics during pregnancy and lactation is associated with an increased risk of developmental disorders. One of the natural medicinal plants-Rhodiola kirilowii, widely used as an immunostimulant in adults-might be a good alternative to antibiotic treatment. The aim of present study was to assess whether daily oral administration of 20 mg/kg of Rhodiola kirilowii aqueous (RKW) or 50% hydroalcoholic (RKW-A) extracts affected hematological and immunological parameters of 6-week-old mouse progeny. There was no significant change in hematological parameters of blood with the exception of hemoglobin, which was significantly higher (about 4%) in RKW group. Offspring of mothers fed Rhodiola kirilowii extracts had increased percentage of granulocytes and decreased percentage of lymphocytes. These changes correlated with decreased percentage of CD3+/CD4+ T-cells (RKW and RKW-A), decrease of CD8+ cells, and increase percentage of NK cells in RKW group. In addition, both types of Rhodiola kirilowii extracts stimulated granulocyte phagocytosis and increased level of respiratory burst. In conclusion, the long-term supplementation of mouse mothers during pregnancy and lactation with RKW or RKW-A extracts affects the immune system of their progeny. These results should be taken into consideration before administration of Rhodiola kirilowii to pregnant and lactating women.

Rhodioloside ameliorates depressive behavior via up-regulation of monoaminergic system activity and anti-inflammatory effect in olfactory bulbectomized rats.

Rhodioloside, a major constituent from roots of Rhodiola rosea, has been previously confirmed to alleviate the hyperactivity in olfactory bulbectomized (OBX) rats exposed to the open field and to decrease the immobility time in the forced swimming test (FST) and tail suspension test (TST). However, its antidepressant effects and mechanisms remain unclear. This study aimed to evaluate the antidepressant effect and the potential mechanisms of rhodioloside in OBX rats. ELISA kits, HPLC-MS and western blot analysis were applied to explore the underlying antidepressant mechanisms of rhodioloside. Rhodioloside (20, 40mg/kg) significantly reversed OBX-induced reduction in sucrose consumption. It was also observed that administration of rhodioloside (20, 40mg/kg) decreased pro-inflammatory cytokines interleukin-1 beta (IL-1ß) and interleukin-6 (IL-6) levels and inhibits nuclear factor-kappa B (NF-κB) activation, as well as normalized the monoaminergic system changes in prefrontal cortex (PFC) of OBX rats. These results confirmed the antidepressant-like effect of rhodioloside, which might be primarily based on its up-regulation of the monoaminergic system activity and anti-inflammatory effect.