ABSTRACT
Ilex rotunda Thunb (IR) is a traditional Chinese medicine used for the clinical treatment of gastric ulcers and duodenal ulcers; however, the effect of IR on ulcerative colitis (UC) and its underlying mechanism remains unclear. This study investigated the therapeutic effect of IR on UC mice induced by dextran sulfate sodium (DSS) as well as the potential underlying mechanism. The main components of IR were analyzed by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. Then we established a model of UC mice by administering 2.0% DSS for 7 days followed by 2 weeks of tap water for three cycles and administered IR. On day 56, the disease activity index (DAI), colon length, pathological changes, and inflammatory response of the colon tissue of mice were assessed. The oxidative stress and apoptosis of colon tissue were detected, and the integrity of the intestinal mucosal barrier was evaluated to assess the effect of IR. Furthermore, the relationship between oncostatin M (OSM) and its receptor (OSMR) in addition to the IR treatment of UC were evaluated using a mouse model and Caco2 cell model. The results showed that IR significantly alleviated the symptoms of UC including rescuing the shortened colon length; reducing DAI scores, serum myeloperoxidase and lipopolysaccharide levels, pathological damage, inflammatory cell infiltration and mRNA levels of interleukin one beta, tumor necrosis factor alpha, and interleukin six in colon tissue; alleviating oxidative stress and apoptosis by decreasing kelch-like ECH-associated protein 1 expression and increasing nuclear factor-erythroid factor 2-related factor 2 and heme oxygenase-1 protein expression; and promoting the regeneration of epithelial cells. IR also promoted the restoration of the intestinal mucosal barrier and modulated the OSM/OSMR pathway to alleviate UC. It was found that IR exerted therapeutic effects on UC by restoring the intestinal mucosal barrier and regulating the OSM/OSMR pathway.
ABSTRACT
High-altitude cerebral oedema (HACE) is a potentially fatal manifestation of high-altitude sickness and is caused partly by inflammation and the blood-brain barrier disruption. Tetrahydrocurcumin (THC) has been reported to exert effective antioxidative and anti-inflammatory effects; This study sought to elucidate the underlying mechanism of THC in mitigating HACE using a mouse model. Our results revealed that prophylactic administration of THC (40 mg/kg) for 3 days significantly alleviated the increase in brain water content (BWC), interleukin-1ß (IL-1ß) and TNF-α levels caused by acute hypobaric hypoxia (AHH). Additionally, superoxide dismutase (SOD) activity was increased by THC to enhance the ability to resist hypoxia. Histological and ultrastructural analysis of the cerebrum revealed that THC administration mitigated AHH-induced pericellular oedema and reduced the perivascular space, resulting in the simultaneous remission of oedema and protection of mitochondria in the cerebrum. In vitro, astrocytes exposed to hypoxia (4% O2 ) for 24 hr exhibited and increase in IL-1ß expression followed by an increase in vascular endothelial growth factor (VEGF) levels. Furthermore, THC administration remarkably downregulated VEGF, matrix metallopeptidase-9 (MMP-9), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) expression, both in vivo and in vitro. Our data highlight the potential prophylactic activity of THC in HACE, it effectively mitigates AHH-induced cerebral oedema and inflammation is associated with the inhibition of the NF-κB/ VEGF/MMP-9 pathways.