The Stem Bark of Kalopanax pictus Exhibits Anti-inflammatory Effect through Heme Oxygenase-1 Induction and NF-κB Suppression

Enhanced biosynthesis of saponins by coronatine in cell suspension culture of Kalopanax septemlobus

Kalopanax septemlobus is a medicinal woody species of the family Araliaceae, and the pharmaceutical properties of saponins obtained from K. septemlobus suggest that K. septemlobus has the potential to be a crude drug and dietary health supplement. In this study, we established cell suspension culture of K. septemlobus to develop a sustainable source of natura-ceuticals. Friable calli were used for establishing cell suspension culture. The maximum amount of total saponins (1.56 mg/60 ml suspension) was obtained during the 15th day of incubation, whereas the maximum capacity of saponin production was reached after day 6 (0.42 μg/mg of fresh weight). The total saponin production in the cell suspension of K. septemlobus was significantly increased by coronatine (COR) at 160% at a dose of 1 μM compared with the mock-treated control, whereas methyl jasmonate treated cells exhibited less increase in total saponin level as compared to the COR-treated cells. In addition, the elicitation of COR strongly induced the expression of beta-amyrin synthase, thus resulting in the accumulation of oleanolic acid (2.369 ± 0.98 μg/mg of extract), a precursor for oleanane-type triterpene saponins. These results indicate that COR is an efficient elicitor for inducing phytochemicals in cell suspension culture and that it provides the possibility for producing saponins of K. septemlobus using cell suspension culture.

Kalopanacis Cortex extract-capped gold nanoparticles activate NRF2 signaling and ameliorate damage in human neuronal SH-SY5Y cells exposed to oxygen-glucose deprivation and reoxygenation

Recently, environment-friendly synthesis of gold nanoparticles (GNPs) has been extensively explored by biologists and chemists. However, significant research is still required to determine whether “eco-friendly” GNPs are beneficial to human health and to elucidate the molecular mechanisms of their effects on human cells. We used human neuronal SH-SY5Y cells to show that treatment with Kalopanacis Cortex extract-capped GNPs (KC-GNs), prepared via an eco-friendly, fast, one-pot synthetic route, protected neuronal cells against oxygen–glucose deprivation/reoxygenation (OGD/R)-induced damage. To prepare GNPs, Kalopanacis Cortex was used without any chemical reducing and stabilizing agents. Ultraviolet–visible spectroscopy showed maximum absorbance at 526 nm owing to KC-GN surface plasmon resonance. Hydrodynamic size (54.02±2.19 nm) and zeta potential (−20.3±0.04 mV) were determined by dynamic light scattering. The average diameter (41.07±3.05 nm) was determined by high-resolution transmission electron microscopy. Energy-dispersive X-ray diffraction spectroscopy and X-ray diffraction confirmed the presence of assembled GNPs. Fourier transform infrared analysis suggested that functional groups such as O–H, C–C, and C–N participated in KC-GN formation. Cell viability assays indicated that KC-GNs restored the viability of OGD/R-treated SH-SY5Y cells. Flow cytometry demonstrated that KC-GNs inhibited the OGD/R-induced reactive oxygen species production and mitochondrial membrane potential disruption. KC-GNs also inhibited the apoptosis of OGD/R-exposed cells. Western blot analysis indicated that the OGD/R-induced cellular apoptosis and simultaneous increases in the expression of cleaved caspase-3, p53, p21, and B-cell lymphoma 2-associated X protein were reversed by KC-GNs. The KC-GN-mediated protection against OGD/R-induced neurotoxicity was diminished by NRF2 and heme oxygenase-1 gene knockdowns. Collectively, these results suggested that KC-GNs exerted strong neuroprotective effects on human neuronal cells, which might be attributed to the attenuation of OGD/R-induced neuronal cell injury through the NRF2 signaling pathway.

Prophylactic and therapeutic treatment with a synthetic analogue of a parasitic worm product prevents experimental arthritis and inhibits IL-1β production via NRF2-mediated counter-regulation of the inflammasome

Rheumatoid arthritis (RA) remains a debilitating autoimmune condition as many patients are refractory to existing conventional and biologic therapies, and hence successful development of novel treatments remains a critical requirement. Towards this, we now describe a synthetic drug-like small molecule analogue, SMA-12b, of an immunomodulatory parasitic worm product, ES-62, which acts both prophylactically and therapeutically against collagen-induced arthritis (CIA) in mice. Mechanistic analysis revealed that SMA-12b modifies the expression of a number of inflammatory response genes, particularly those associated with the inflammasome in mouse bone marrow-derived macrophages and indeed IL-1β was the most down-regulated gene. Consistent with this, IL-1β was significantly reduced in the joints of mice with CIA treated with SMA-12b. SMA-12b also increased the expression of a number of genes associated with anti-oxidant responses that are controlled by the transcription factor NRF2 and critically, was unable to inhibit expression of IL-1β by macrophages derived from the bone marrow of NRF2(-/-) mice. Collectively, these data suggest that SMA-12b could provide the basis of an entirely novel approach to fulfilling the urgent need for new treatments for RA.