Antrodia camphorata suppresses lipopolysaccharide-induced nuclear factor-κB activation in transgenic mice evaluated by bioluminescence imaging

Abstract

In an earlier study, we found that Antrodia camphorata inhibited the production of lipopolysaccharide (LPS)-induced cytokines, inducible nitric oxide synthase, and cyclooxygenase-2 by blocking nuclear factor-κB (NF-κB) activation in cultured RAW 264.7 macrophages. This study was aimed at evaluating the inhibitory effects of the fermented culture broth of A. camphorata in terms of LPS-induced NF-κB activation in transgenic mice by using a non-invasive, real-time NF-κB bioluminescence imaging technique. Transgenic mice carrying the luciferase gene under the control of NF-κB were given A. camphorata (570 mg/kg, p.o.) for three consecutive days and then injected with LPS (4 mg/kg, i.p.). In vivo imaging showed that treatment with LPS increased the luminescent signal, whereas A. camphorata suppressed the LPS-induced inflammatory response significantly. Ex vivo imaging showed that A. camphorata suppressed LPS-induced NF-κB activity in the small intestine, mesenteric lymph nodes, liver, spleen, and kidney. Immunohistochemical staining revealed that A. camphorata suppressed production of the LPS-induced tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and NF-κB p65 subunit in these organs. Furthermore, A. camphorata attenuated the productions of LPS-induced TNF-α and IL-1β in serum from transgenic mice. We report the first confirmation of the anti-inflammatory action in vivo of this potentially beneficial mushroom.