Search Results (3)

Foot-and-mouth disease virus (FMDV) belongs to the Picornaviridae family and is an important pathogen affecting cloven-hoof livestock. However, neither effective vaccines covering all serotypes nor specific antivirals against FMDV infections are currently available. In this study, we employed virtual screening to screen for secondary metabolite terpenoids targeting the RNA-dependent RNA polymerase (RdRp), or 3D^pol, of FMDV. Subsequently, we identified the potential antiviral activity of the 32 top-ranked terpenoids, revealing that continentalic acid, dehydroabietic acid (abietic diterpenoids), brusatol, bruceine D, and bruceine E (tetracyclic triterpenoids) significantly reduced cytopathic effects and viral infection in the terpenoid-treated, FMDV-infected BHK-21 cells in a dose-dependent manner, with nanomolar to low micromolar levels. The FMDV minigenome assay demonstrated that brusatol and bruceine D, in particular, effectively blocked FMDV 3D^pol activity, exhibiting IC50 values in the range of 0.37–0.39 µM and surpassing the efficacy of the antiviral drug control, ribavirin. Continentalic acid and bruceine E exhibited moderate inhibition of FMDV 3D^pol. The predicted protein–ligand interaction confirmed that these potential terpenoids interacted with the main catalytic and bystander residues of FMDV 3D^pol. Additionally, brusatol and bruceine D exhibited additive effects when combined with ribavirin. In conclusion, terpenoids from natural resources show promise for the development of anti-FMD agents. Full article

Aralia continentalis has been used in Korea as a folk remedy for arthralgia, rheumatism, and inflammation. However, its anti-lymphoma effect remains uncharacterized. Here, we demonstrate that A. continentalis extract and its three diterpenes efficiently kill B-lymphoma cells. Our in vitro and in vivo results suggest that the cytotoxic activities of continentalic acid, a major diterpene from A. continentalis extract, are specific towards cancer cells while leaving normal murine cells and tissues unharmed. Mechanistically, continentalic acid represses the expression of pro-survival Bcl-2 family members, such as Mcl-1 and Bcl-xL. It dissociates the mitochondrial membrane potential, leading to the stimulation of effector caspase 3/7 activities and, ultimately, cell death. Intriguingly, this agent therapeutically synergizes with roflumilast, a pan-PDE4 inhibitor that has been successfully repurposed for the treatment of aggressive B-cell malignancies in recent clinical tests. Our findings unveiled that A. continentalis extract and three of the plant’s diterpenes exhibit anti-cancer activities. We also demonstrate the synergistic inhibitory effect of continentalic acid on the survival of B-lymphoma cells when combined with roflumilast. Taken in conjunction, continentalic acid may hold significant potential for the treatment of B-cell lymphoma. Full article

The aim of this study was to identify the active compound responsible for the pharmacological activities of Manchurian spikenard (Aralia continentalis Kitag.). Interleukin (IL)-1β-stimulated human chondrocytes and monoiodoacetate (MIA)-induced osteoarthritic rats were treated with the 50% ethanolic extract of spikenard or its major components, such as continentalic acid (ent-pimara-8(14),15-diene-19-oic acid) and kaurenoic acid (ent-kaura-16-en-19-oic acid). The spikenard extract significantly inhibited IL-1β-stimulated production of IL-6, IL-8, metalloproteinase (MMP)-1, MMP-13, cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) and prostaglandin(PG)E2 in a dose-dependent manner but not MMP-3 production. The extract also inhibited the IL-1β-induced translocation of NF-κB/p65 into the nucleus and dose-dependent phosphorylation levels of extracellular signal-regulated kinase (ERK), Jun amino-terminal kinase (JNK) and p38 mitogen-activated protein (MAP) kinase. Continentalic acid exhibited significant anti-arthritic activity corresponding exactly to that of the extract containing an equivalent amount of continentalic acid. On the other hand, kaurenoic acid exhibited a compatible activity at about a 10-times higher molar concentration than that of continentalic acid. In vitro anti-arthritic activities of the spikenard extract and continentalic acid were also confirmed in MIA-induced osteoarthritic rats. The 50% ethanolic extract of Manchurian spikenard exhibited promising anti-arthritic activities in the in vitro and in vivo osteoarthritis models, and continentalic acid, not kaurenoic acid, was most probably responsible for those activities. Full article