Anti-Inflammatory Effects of Spirodela polyrhiza (L.) SCHLEID. Extract on Contact Dermatitis in Mice-Its Active Compounds and Molecular Targets.

Spirodela polyrhiza (L.) SCHLEID. has been used to treat epidemic fever, dysuria, and various skin ailments, such as measles eruptions, eczema, and pruritus, in China, Japan, and Korea. In this study, the active compounds in S. polyrhiza and their target genes were identified by network-based analysis. Moreover, the study evaluated the effects of a 70% ethanolic extract of S. polyrhiza (EESP) on skin lesions, histopathological changes, inflammatory cytokines, and chemokines in mice with contact dermatitis (CD) induced by 1-fluoro-2,4-dinitrobenzene (DNFB), and examined the inhibitory effects of EESP on mitogen-activated protein kinase (MAPK) signalling pathways. In our results, 14 active compounds and 29 CD-related target genes were identified. Among them, tumour necrosis factor (TNF) and interleukin 6 (IL-6) were identified as hub genes, and luteolin and apigenin showed a strong binding affinity with TNF (<-8 kcal/mol) and IL-6 (<-6 kcal/mol). Our in vivo studies showed that topical EESP ameliorated DNFB-induced skin lesions and histopathological abnormalities, and reduced the levels of TNF-α, interferon (IFN)-É£, IL-6, and monocyte chemotactic protein (MCP)-1 in inflamed tissues. In conclusion, our findings suggest the potential for dermatological applications of S. polyrhiza and suggest that its anti-dermatitis action is related to the inhibition of TNF and IL-6 by luteolin and luteolin glycosides.

Screening ginseng saponins in progenitor cells identifies 20(R)-ginsenoside Rh2 as an enhancer of skeletal and cardiac muscle regeneration.

Aging is associated with increased prevalence of skeletal and cardiac muscle disorders, such as sarcopenia and cardiac infarction. In this study, we constructed a compendium of purified ginsenoside compounds from Panax ginseng C.A. Meyer, which is a traditional Korean medicinal plant used to treat for muscle weakness. Skeletal muscle progenitor cell-based screening identified three compounds that enhance cell viability, of which 20(R)-ginsenoside Rh2 showed the most robust response. 20(R)-ginsenoside Rh2 increased viability in myoblasts and cardiomyocytes, but not fibroblasts or disease-related cells. The cellular mechanism was identified as downregulation of cyclin-dependent kinase inhibitor 1B (p27Kip1) via upregulation of Akt1/PKB phosphorylation at serine 473, with the orientation of the 20 carbon epimer being crucially important for biological activity. In zebrafish and mammalian models, 20(R)-ginsenoside Rh2 enhanced muscle cell proliferation and accelerated recovery from degeneration. Thus, we have identified 20(R)-ginsenoside Rh2 as a p27Kip1 inhibitor that may be developed as a natural therapeutic for muscle degeneration.

Bioactive Metabolites from the Fruits of Psoralea corylifolia.

Twenty-four metabolites, including seven new compounds (1-7), were isolated from the dried fruits of Psoralea corylifolia. On the basis of combined spectroscopic and chemical analysis, the new compounds were determined to be six flavonoids (1-6) and a meroterpenoid (7). The absolute configurations of the natural products obtained, including the previously undetermined 16 and 17, were assigned by several methods, such as NOE spectroscopy, optical rotation, and CD spectroscopy. Several of these compounds exhibited moderate inhibitory activity toward Staphylococcus mutans-derived SrtA (2, 6, and 16) and significant stimulation of SIRT1 activity (2, 3, and 15).

Dammarane triterpenes as potential SIRT1 activators from the leaves of Panax ginseng.

During a search for SIRT1 activators originating in nature, three new dammarane triterpenes, 6α,20(S)-dihydroxydammar-3,12-dione-24-ene (1), 6α,20(S),24(S)-trihydroxydammar-3,12-dione-25-ene (2), and 6α,20(S),25-trihydroxydammar-3,12-dione-23-ene (3), as well as two known triterpenes, dammar-20(22),24-diene-3ß,6α,12ß-triol (4) and 20(S)-ginsenoside Rg3 (5), were isolated from Panax ginseng leaves. Compounds 1 and 3-5 showed potential as SIRT1 activators, as analyzed by in vitro enzyme-based SIRT1-NAD/NADH and SIRT1-p53 luciferase cell-based assays. They were also found to increase the level of NAD(+)/NADH ratio in HEK293 cells. This study presents a new class of chemical entities that may be able to be developed as SIRT1 activators for antiaging and treatment of age-associated diseases.