Biochim Biophys Acta. 2006 Mar;1760(3):487-94. |
Centaureidin promotes dendrite retraction of melanocytes by activating Rho.[Pubmed: 16476521] |
METHODS AND RESULTS: Centaureidin induces significant morphological changes in normal human epidermal melanocytes and inhibits melanocyte dendrite elongation, resulting in a reduction of melanosome transfer in an in vitro melanocyte-keratinocyte co-culture system. We studied the effects of Centaureidin on the small GTPases. In in vitro binding assay, Centaureidin activated Rho and furthermore, a Rho inhibitor (C. botulinum C3 exoenzyme), a Rho kinase inhibitor (Y27632) and a small GTPase inhibitor (Toxin B) blocked dendrite retraction induced by Centaureidin.
CONCLUSIONS:
These results suggest Centaureidin could act via the Rho signaling pathway, and it may directly or indirectly activate Rho. Thus, Centaureidin appears to inhibit dendrite outgrowth from melanocytes by activating Rho, resulting in the inhibition of melanosome transfer from melanocytes to keratinocytes. |
Planta Med. 1998 Mar;64(2):116-9. |
Preliminary study of the potential vasodilator effects on rat aorta of centaurein and centaureidin, two flavonoids from Centaurea corcubionensis.[Pubmed: 9580164] |
METHODS AND RESULTS:
In this work, the potential vasorelaxant activity of centaurein and Centaureidin, two flavonoids from Centaurea corcubionensis, were studied for the first time in rat aorta. Centaureidin (10 microM-0.1 mM) totally relaxed, in a concentration-dependent manner and with almost equal effectiveness, the contractions induced by NA (IC50 = 16.7 +/- 1.9 microM) or by a high K+ concentration (IC50 = 16.1 +/- 3.1 microM) in intact rat aortic rings. Mechanical removal of endothelium did not significantly modify the vasoralexant effects of this flavone (IC50 = 20.8 +/- 2.4 microM for NA; IC50 = 21 +/- 2.9 microM for K+). On the other hand, centaurein (1 microM-0.1 mM) had no effect on NA- and high K(+)-induced contractions in rubbed and intact rat aortic rings.
CONCLUSIONS:
These results indicate that substitution by glucose in the chemical structure of Centaureidin leads to the loss of its vasodilator activity. |
J Ethnopharmacol. 2007 Jun 13;112(2):232-6. |
Flavonoids, centaurein and centaureidin, from Bidens pilosa, stimulate IFN-gamma expression.[Pubmed: 17408892] |
METHODS AND RESULTS:
Centaurein (EC(50)=75 microg/ml) and its aglycone, Centaureidin (EC(50)=0.9 microg/ml), isolated from this butanol subfraction, augmented IFN-gamma promoter activity by approximately four-fold. |