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).

Sortase A inhibitory metabolites from the roots of Pulsatilla koreana.

Three new lignans (3, 4, and 6) along with eight known lignans and phenyl propanoids were isolated from the dried roots of Pulsatilla koreana, an oriental folk medicine. Based upon the results of combined spectroscopic and chemical methods, the structures of new compounds were determined to be lignan glycosides. Included among the known compounds are three compounds (5, 7, and 8) isolated first time from this plant as well as two compounds (2 and 11) previously reported only as synthetic derivatives. These compounds significantly inhibited the action of Sortase A from Streptococcus mutans OMZ65, an isolate from human oral cavity.

Suvanine sesterterpenes and deacyl irciniasulfonic acids from a tropical Coscinoderma sp. sponge.

The suvanines, a new suvanine salt, five new (2, 4-8) and two known sesterterpenes from the same structural class, and two new modified lipids (9 and 10) were isolated from a Coscinoderma sp. sponge collected from Chuuk Island, Micronesia. On the basis of the results of combined spectroscopic and chemical analyses, a new suvanine salt was determined to be the suvanine N,N-dimethyl-1,3-dimethylherbipoline salt (2) and suvanine-lactam derivatives (4-8) formed by condensations between an oxidized furan moiety and amino acids. The lipid metabolites were found to be new derivatives of the taurine-containing deacyl irciniasulfonic acid class. The suvanines exhibited moderate cytotoxicities against the K562 and A549 cell lines, while the new suvanine salt (2) had significant antibacterial activity.

Kurarinone regulates immune responses through regulation of the JAK/STAT and TCR-mediated signaling pathways.

Sophora flavescens is a medicinal herb that contains flavonoids and quinolizidine alkaloids and has a wide range of biological activities due to its anti-inflammatory, anti-bacterial and anti-cancer properties. We isolated a series of flavonoids from the roots of Sophora flavescens and examined their ability to inhibit immune responses. Among the flavonoids, kurarinone exhibited the strongest inhibitory effect on immune responses. Kurarinone suppressed the differentiation of CD4(+) T cells by inhibiting the expression and production of T-cell lineage-specific master regulators and cytokines. Our results also demonstrated that kurarinone directly suppressed the cytokine-induced Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling and T-cell receptor (TCR) pathways. In two established animal models of chronic inflammatory skin disease, one in which psoriasis-like skin disease was induced by an interleukin 23 (IL-23) injection into mouse ears and another in which 2,4,6-trinitrochlorobenzene (TNCB) application on the abdomens of mice was used to induce contact dermatitis, kurarinone repressed disease development by inhibiting the expression of pro-inflammatory mediators, including cytokines, chemokines and enzyme in murine ear skin. This study provides new evidence that kurarinone may ameliorate chronic inflammatory skin diseases through the suppression of pathogenic CD4(+) T-cell differentiation and the overall immune response.