||Oroxylin A has anticancer,.anti-inflammation, antithrombotic,antibacterial, anti-pruritic
effects, it can inhibit LPS-induced iNOS and COX-2 gene expression by blocking NF-κB activation. Oroxylin A reverses MDR by G2/M arrest and the underlying mechanism attributed to the suppression of P-gp expression via Chk2/P53/NF-κB signaling pathway. Oroxylin A facilitates memory consolidation through brain-derived neurotrophic factor (BDNF)-TrkB signaling.
||TNF-α | ERK | MMP(e.g.TIMP) | NF-kB | Chk | p53 | P-gp | Akt | NOS | COX | PGE | Bcl-2/Bax | NO|
|Arch Pharm Res. 2014 May;37(5):679-86. |
|Antithrombotic activities of oroxylin A in vitro and in vivo.[Pubmed: 23963976]|
METHODS AND RESULTS:
Here, the anticoagulant activities of Oroxylin A (OroA), a major component of Scutellaria baicalensis Georgi, were examined by monitoring activated partial thromboplastin time (aPTT), prothrombin time (PT), and the activities of cell-based thrombin and activated factor X (FXa). Furthermore, the effects of OroA on the expressions of plasminogen activator inhibitor type 1 (PAI-1) and tissue-type plasminogen activator (t-PA) were tested in tumor necrosis factor (TNF)-α activated human umbilical vein endothelial cells (HUVECs). Treatment with OroA resulted in prolonged aPTT and PT and inhibition of the activities of thrombin and FXa, and OroA inhibited production of thrombin and FXa in HUVECs. And OroA inhibited thrombin-catalyzed fibrin polymerization and platelet aggregation. In accordance with these anticoagulant activities, OroA elicited anticoagulant effects in mouse. In addition, treatment of OroA resulted in the inhibition of TNF-α-induced production of PAI-1, and treatment with OroA resulted in the significant reduction of the PAI-1 to t-PA ratio.
Collectively, OroA possess antithrombotic activities and offer bases for development of a novel anticoagulant.
|Eur. J. Pharmacol., 2009, 603(1-3):22-8. |
|Oroxylin A suppresses invasion through down-regulating the expression of matrix metalloproteinase-2/9 in MDA-MB-435 human breast cancer cells.[Pubmed: 19100732]|
|Our previous study revealed that Oroxylin A, a naturally occurring monoflavonoid isolated from Scutellariae radix, could inhibit the proliferation of human hepatocellular carcinoma HepG2 cells through inducing the apoptosis in these cells. However, the molecular mechanism of its anticancer activity remains poorly understood and warrants further investigations.
In this study, we examined the anti-invasive activities of Oroxylin A in vitro. The results showed that Oroxylin A suppressed MDA-MB-435 cell adhesion to the fibronectin-coated substrate in a concentration-dependent manner. It inhibited the wound healing migration of MDA-MB-435 cells and invasion of MDA-MB-435 cells through reconstituted extracellular matrix (matrigel). Zymography revealed that Oroxylin A decreased the secretion of matrix metalloproteinases-2 (MMP-2) and metalloproteinases-9 (MMP-9). Oroxylin A also inhibited the expressions of MMP-2 and MMP-9 in MDA-MB-435 cells. Additionally, Oroxylin A exerted an inhibitory effect on the phosphorylation of extracellular regulated proteinkinases1/2 (ERK1/2). Collectively, these data provided a molecular basis for the antiinvasive effects of Oroxylin A.
Taken together, these findings strongly suggest that Oroxylin A had potential anti-metastatic effect in vitro and shed light on the investigation of Oroxylin A on breast cancer metastasis in vivo.
|Brain Res Bull. 2014 Sep;108:67-73. |
|Oroxylin A enhances memory consolidation through the brain-derived neurotrophic factor in mice.[Pubmed: 25218897]|
|Memory consolidation is a process by which acquired information is transformed from a labile into a more stable state that can be retrieved at a later time. In the present study, we investigated the role of Oroxylin A on the memory consolidation process in mice.
METHODS AND RESULTS:
Oroxylin A improved the memory retention administered at 0 h, 1 h and 3 h after training in a passive avoidance task, suggesting that Oroxylin A facilitates memory consolidation. Oroxylin A increased mature brain-derived neurotrophic factor (mBDNF) levels in the hippocampus from 6h to 24h after administration. Moreover, 3h post-training administration of Oroxylin A enhanced the mBDNF level at 9h after the acquisition trial compared to the level at 6h after the acquisition trial. However, 6h post-training administration of Oroxylin A did not increase the mBDNF level at 9h after the acquisition trial. Blocking mBDNF signaling with recombinant tropomyosin receptor kinase B (TrkB)-Fc or k252a at 9h after the acquisition trial obstructed the effect of Oroxylin A on memory consolidation.
Taken together, our data suggest that Oroxylin A facilitates memory consolidation through BDNF-TrkB signaling and confirms that the increase of BDNF in a specific time window plays a crucial role in memory consolidation.
|Acta Pharmacol Sin. 2010 Jun;31(6):718-24. |
|Anti-pruritic effect of baicalin and its metabolites, baicalein and oroxylin A, in mice.[Pubmed: 20453872 ]|
|To explore whether intestinal microflora plays a role in anti-pruritic activity of baicalin, a main constituent of the rhizome of Scutellaria baicalensis (SB).
METHODS AND RESULTS:
Baicalin was anaerobically incubated with human fecal microflora, and its metabolites, baicalein and Oroxylin A, were isolated. The inhibitory effect of baicalin and its metabolites was accessed in histamine- or compound 48/80-induced scratching behavior in mice.
Baicalin was metabolized to baicalein and Oroxylin A, with metabolic activities of 40.2+/-26.2 and 1.2+/-1.1 nmol.h(-1).mg(-1) wet weight of human fecal microflora, respectively. Baicalin (20, 50 mg/kg) showed more potent inhibitory effect on histamine-induced scratching behavior when orally administered than intraperitoneally. In contrast, baicalein and Oroxylin A had more potent inhibitory effect when the intraperitoneally administered. The anti-scratching behavior activity of oral baicalin and its metabolites was in proportion to their inhibition on histamine-induced increase of vascular permeability with Oroxylin A more potent than baicalein and baicalin. In Magnus test using guinea pig ileum, Oroxylin A is more potent than baicalein and baicalin in inhibition of histamine-induced contraction. The anti-scratching behavioral effect of oral baicalin was significantly reduced when oral antibiotics were simultaneously administered, whereas the effect of baicalein and Oroxylin A were not affected.
Oral baicalin may be metabolized by intestinal microflora into baicalein and Oroxylin A, which ameliorate pruritic reactions through anti-histamine action.