Aralia cordata Extract Activates NF-κB and MAPK Signaling Pathways and Induces Pro-inflammatory Changes in RAW264.7 Macrophages

Macrophages play essential roles in innate immune responses by producing various immune mediators. Therefore, modulating macrophage function is an attractive strategy to treat immune disorders. Aralia cordata var. continentalis (AC), known as “Dokwhal” in Korea, possesses various biological and medicinal functions, including immunomodulation. The present study investigated the effect of the hot water extract of AC (HAC) on RAW264.7 murine macrophages. When these cells were treated with HAC, nitric oxide production and inducible nitric oxide synthase expression was induced dose-dependently. In addition, HAC treatment triggered the secretion of innate immune cytokines, such as TNF-α and IL-6. Phagocytosis, measured by FITC-dextran internalization showed that HAC stimulated the phagocytic activity of macrophages. Furthermore, HAC promoted the production of reactive oxygen species in RAW264.7 cells, determined by CM-H2DCFDA. In addition, the immunoblot analysis of intracellular signaling proteins revealed that NF-kB and MAPK signaling pathways, which are important signaling mediators of inflammation, are upregulated by HAC. In conclusion, these findings suggested that HAC can stimulate macrophage activity, and NF-kB and MAPK signaling pathways might be involved in the immunostimulatory effects of HAC.

An Antioxidant Davallialactone from Phellinus baumii Enhances Sperm Penetration on In Vitro Fertilization of Pigs

Davallialactone (DAVA) is a hispidin analogue derived from the medicinal fungus Phellinus baumii. We examined the effect of DAVA on in vitro fertilization (IVF) of pigs. Boar spermatozoa were incubated in fertilization medium with varying concentrations of DAVA, then sperm motility and reactive oxygen species (ROS) level were evaluated. Higher sperm motility was found following the addition of 0.5 or 1 µM DAVA after incubation than addition of other concentrations or controls. ROS level decreased significantly with the addition of DAVA. The rate of normal fertilization was higher in the presence of 1 µM DAVA (65.1%) than were those of other concentrations or controls (45.4~59.4%), and the highest total fertilization rate (mono- and polyspermic oocytes) was observed at 1 µM DAVA (83%). In conclusion, addition of DAVA to fertilization medium improved sperm motility, and reduced ROS level so as to potentially improve sperm-oocyte binding in IVF, suggesting the potential of a compound isolated from mushrooms in assisted reproductive technology for humans and animals.

Methyl 9-Oxo-(10E,12E)-octadecadienoate Isolated from Fomes fomentarius Attenuates Lipopolysaccharide-Induced Inflammatory Response by Blocking Phosphorylation of STAT3 in Murine Macrophages

Fomes fomentarius is a fungus of the Polyporaceae family and is used in traditional oriental therapies. Although the anti-inflammatory activities of this species have been previously reported, the identity of the bioactive compounds responsible for this activity remains unknown. Here, we investigated whether methyl 9-oxo-(10E,12E)-octadecadienoate (FF-8) purified from F. fomentarius exerts anti-inflammatory activity in murine macrophages stimulated with lipopolysaccharide (LPS). FF-8 suppressed secretion of nitric oxide (NO) and prostaglandin E2 through downregulation of inducible NO synthase and cyclooxygenase-2 expression induced by LPS. In addition, pretreatment of cells with FF-8 led to a reduction in levels of secreted inflammatory cytokines such as tumor necrosis factor-alpha and interleukin-6 in macrophages stimulated with LPS. Conversely, FF-8 did not affect nuclear factor kappaB, p38, c-Jun NH2-terminal kinase, and extracellular signal-regulated kinase pathways. Instead, FF-8 specifically interfered with signal transducer and activator of transcription 3 (STAT3) phosphorylation induced by LPS. Collectively, this study demonstrated that FF-8 purified from F. fomentarius suppresses inflammatory responses in macrophages stimulated with LPS by inhibiting STAT3 activation. Further studies will be required to elucidate the anti-inflammatory effect of FF-8 in vivo.

Differential Modulation of Lipopolysaccharide-Induced Inflammatory Cytokine Production by and Antioxidant Activity of Fomentariol in RAW264.7 Cells

Medicinal mushrooms have been used worldwide to treat cancer and modulate the immune system. Over the last several years, there has been increasing interest in isolating bioactive compounds from medicinal mushrooms and evaluating their health beneficial effects. Fomes fomentarius is used in traditional oriental medicine and is known to possess antioxidant, anti-inflammatory, antidiabetic, and antitumor effects. In the present study, we isolated fomentariol from Fomes fomentarius and investigated its anti-inflammatory effect in murine macrophages (RAW264.7 cells) stimulated with lipopolysaccharides. Fomentariol inhibited the production of nitric oxide and intracellular reactive oxygen species triggered by lipopolysaccharides. Interestingly, fomentariol differentially regulated cytokine production triggered by lipopolysaccharides. Fomentariol effectively suppressed the production of interleukin-1beta and interleukin-6 but not tumor necrosis factor-alpha. The inhibitory effect of fomentariol against nitric oxide, interleukin-1beta, and interleukin-6 production was possibly mediated by downregulation of the extracellular signal-regulated kinase signaling pathway. Taken together, our results suggest that fomentariol differentially modulated inflammatory responses triggered by lipopolysaccharides in macrophages and is one of the bioactive compounds that mediate the physiological effects of Fomes fomentarius.