Hypericum sampsonii exhibits anti-inflammatory activity in a lipopolysaccharide-induced sepsis mouse model

Background and aim

Sepsis causes an uncontrolled systemic response characterized by excessive inflammation and immune suppression, leading to multiple organ failure and death. An effective therapeutic strategy for sepsis-related syndromes is urgently needed. Hypericum sampsonii Hance (HS) is a folk herbal plant used to treat arthritis and dermatitis, but the anti-inflammatory properties of HS and its related compounds have rarely been investigated. In this study, we aimed to explore the anti-inflammatory effects of HS.

Experimental procedure

Models of bacterial lipopolysaccharide (LPS)-induced activated macrophages and endotoxemia mice were used, in which the TLR4/NF-κB signaling pathway is upregulated to trigger inflammatory responses. The HS extract (HSE) was delivered into LPS-induced endotoxemia mice via oral administration. Three compounds were purified using column chromatography and preparative thin layer chromatography and were validated by physical and spectroscopic data.

Results

HSE suppressed NF-κB activation and proinflammatory molecules (TNF-α, IL-6, iNOS) in LPS-activated RAW 264.7 macrophages. Furthermore, oral administration of HSE (200 mg/kg) to LPS-treated mice improved the survival rate, restored body temperature, decreased TNF-α and IL-6 in serum, and reduced IL-6 expression in bronchoalveolar lavage fluid (BALF). In lung tissues, HSE reduced LPS-induced leukocyte infiltration and the expression of proinflammatory molecules (TNF-α, IL-6, iNOS, CCL4 and CCL5). Three pure compounds isolated from HSE, including 2,4,6-trihydroxybenzophenone-4-O-geranyl ether, 1-hydroxy-7 methoxyxanthone and euxanthone, were demonstrated to exhibit anti-inflammatory activities in LPS-stimulated RAW 264.7 macrophages.

Conclusion

The present study demonstrated the anti-inflammatory effects of HS in vitro and in vivo. Further clinical studies of HS in human sepsis are warranted.