Ouabain modulates airway remodeling caused by Th2-high asthma in mice.

OBJECTIVE: Ouabain, an inhibitor of Na+/K+-ATPase, is a type of endogenous hormone synthesized in the adrenal cortex and hypothalamus. Previous studies found that ouabain potently inhibited acute inflammatory reactions such as type 2 inflammation and regulated immunological processes. In this study, we aimed to investigate ouabain effect on allergic asthma. METHODS: BALB/c mice were submitted to chronic airway allergic inflammation induced by an ovalbumin (OVA) protocol. The animals were treated with ouabain or standard drug, budesonide. The following parameters were evaluated: cell migration, cytokine profile, IgE levels, lung histological modifications and MAPK activation. RESULTS: At first, it was observed that ouabain reduced OVA-induced cell migration into the lung, observed by bronchoalveolar lavage fluid (BALF) cell counting and lung histological analysis (HE stain). Additionally, ouabain negatively modulated alarmins (IL-33 and TSLP), Th2 high cytokines levels (IL-1ß and IL-4) and tissue remodeling markers such as TNF-α and TGF-ß. Treatment with ouabain also reduced OVA-specific IgE titers in BALF and serum, respectively, when compared to the OVA group. Lung histological parameters, including collagen deposition and mucus production induced by OVA were also attenuated by ouabain treatment. Finally, our results showed that p38 mitogen-activated protein kinase (MAPK) signaling pathways were suppressed by ouabain in this model. All these parameters were reduced by budesonide, a steroidal anti-inflammatory standard drug. CONCLUSION: These data together suggest that, in addition to its acute anti-inflammatory action, ouabain is also able to modulate allergic asthma.

2-Allylphenol Reduces IL-1ß and TNF-α, Promoting Antinociception through Adenosinergic, Anti-Inflammatory, and Antioxidant Mechanisms.

2-Allylphenol (2-AP) is a synthetic phenylpropanoid, structurally related to cardanol, thymol, and ortho-eugenol. Phenylpropanoids are described in the literature as being capable of promoting biological activity. Due to the similarity between 2-AP and other bioactive phenylpropanoids, the present research aims at evaluating the antioxidant, antinociceptive, and anti-inflammatory potential of 2-AP in silico, in vitro, and in vivo. At 30 min prior to the start of in vivo pharmacological testing, administration of 2-AP (25, 50, 75, and 100 mg/kg i.p.), morphine (6 mg/kg i.p.), dexamethasone (2 mg/kg s.c.), or vehicle alone was performed. In the acetic acid-induced abdominal writhing tests, pretreatment with 2-AP significantly reduced the number of abdominal writhes, as well as decreased licking times in the glutamate and formalin tests. Investigation of the mechanism of action using the formalin model led to the conclusion that the opioid system does not participate in its activity. However, the adenosinergic system is involved. In the peritonitis tests, 2-AP inhibited leukocyte migration and reduced releases of proinflammatory mediators TNF-α and IL-1ß. In vitro antioxidant assays demonstrated that 2-AP presents significant ability to sequester superoxide radicals. In silico docking studies confirmed interaction between 2-AP and the adenosine A2a receptor through hydrogen bonds with the critical asparagine 253 residues present in the active site. Investigation of 2-AP demonstrated its nociception inhibition and ability to reduce reactive oxygen species. Its interaction with A2a receptors may well be related to proinflammatory cytokines TNF-α and IL-1ß reduction activity, corroborating its antinociceptive effect.