Three New Ionone Glycosides from Rhododendron capitatum Maxim.

Six ionone glycosides (1-3 and 5-7), including three new ones, named capitsesqsides A-C (1-3), together with an eudesmane sesquiterpenoid glycoside (4) and three known triterpenoid saponins (8-10) were isolated from Rhododendron capitatum. The structures of these compounds were determined by extensive spectroscopic techniques (MS, UV, 1D-NMR, and 2D-NMR) and comparison with data reported in the literature. The absolute configurations were determined by comparison of the experimental and theoretically calculated ECD curves and LC-MS analyses after acid hydrolysis and derivatization. The anti-inflammatory activities of these compounds were evaluated in the LPS-induced RAW264.7 cells. Molecular docking demonstrated that 2 has a favorable affinity for NLRP3 and iNOS.

Neuroprotective effects of a new triterpenoid from edible mushroom on oxidative stress and apoptosis through the BDNF/TrkB/ERK/CREB and Nrf2 signaling pathway in vitro and in vivo.

Inonotus obliquus (Fr.) Pilat is an edible mushroom which is used to produce tea and syrup due to its medicinal properties. In this study, 10 secondary metabolites (1-10), including a new lanostane triterpenoid named 2α-hydroxy-inotodiol (2α-HI, 1), were identified from the edible mushroom I. obliquus through high-resolution electrospray ionization mass spectrometry (HRESIMS) and nuclear magnetic resonance spectroscopy (NMR) data analysis. The neuroprotective function of all steroidal metabolites in H2O2-induced SH-SY5Y cells was investigated. The results showed that 2α-HI exhibited the most remarkable neuroprotective activity. In the meantime, 2α-HI significantly ameliorated oxidative stress damage, reactive oxygen species (ROS) accumulation and mitochondrial damage induced by H2O2 in SH-SY5Y cells. The Nrf2 siRNA and inhibitors transfected the SH-SY5Y cells, indicating the Nrf2 and BDNF/TrkB/ERK/CREB pathway mediated the neuroprotective effects of 2α-HI against the H2O2-stimulated oxidative stress and apoptosis. Moreover, the neuroprotection of 2α-HI was preliminarily verified in zebrafish. In conclusion, this research was the first to confirm that 2α-HI could effectively protect SH-SY5Y cells against H2O2-induced oxidative stress and apoptosis via the Nrf2 and BDNF/TrkB/ERK/CREB signaling pathway. Hence, this mushroom could be a potential dietary supplement to ameliorate neurodegenerative diseases.

Triterpenoids and meroterpenoids from the edible Ganoderma resinaceum and their potential anti-inflammatory, antioxidant and anti-apoptosis activities.

Ganoderma resinaceum, as a traditional edible mushroom, has been widely reported to improve neurodegenerative diseases characterized by oxidative stress and inflammation. In this study, five new terpenoids, including four lanostane triterpenoids, named ganoresinoid A-D (1-4) and one meroterpenoid, named ganoresinoid E (5), along with 27 known compounds (6-32), were isolated from the fruiting bodies of edible mushroom G. resinaceum. These structures were identified by NMR, HRESIMS data analysis. All metabolites were evaluated for anti-inflammatory, antioxidative and anti-apoptosis activities. Among them, ganoresinoid A showed notably restrained nitric oxide (NO), IL-1ß, IL-6 and TNF-α levels in LPS-activated BV-2 microglial cells via suppressing TLR-4/ NF-κB and MAPK signaling pathway. Simultaneously, ganoresinoid A remarkably alleviated LPS-induced apoptosis by means of the decrease of mitochondrial membrane potential (MMP) and reactive oxygen species (ROS). In addition, ganoresinoid A demonstrated antioxidant effects in H2O2-induced SH-SY5Y cells by activating the Akt/GSK-3ß/Nrf2 signaling pathway. Taken together, these results may provide a stronger theoretical basis for ganoresinoid A from G. resinaceum as nutrition intervention to alleviate neurodegenerative diseases.