Effect of Ayurved Siriraj herbal recipe Chantaleela on platelet aggregation.

INTRODUCTION: Ayurved Siriraj Chantaleela recipe is a traditional Thai remedy consisting of eight medicinal plants, which is employed for the treatment of fever. OBJECTIVE: To investigate the effects of Ayurved Siriraj Herbal recipe Chantaleela on platelet aggregation. STUDY DESIGN: Clinical research; ex vivo with before and after study design. MATERIAL AND METHOD: Twelve healthy male and female volunteers participated in the present study. Platelet aggregation test before Chantaleela ingestion was done as a control. After administration of 750 mg Chantaleela (3 x 250 mg tablets) every 8 hours for 3 doses, platelet aggregation was measured 8 hours following the first dose using an aggregometer and microplate reader. Adrenaline (Adr) and adenosine diphosphate (ADP) were used as platelet stimulants. Platelet aggregation was measured again at 32 hours and 8-10 days after the first dose. RESULTS: All of the participants completed the present study without any adverse event. Ayurved Siriraj Chantaleela did not affect platelet aggregation; neither Adr nor ADP were used as platelet agonists in both aggregometer and microplate reader Subgroup analysis revealed no significant change in platelet aggregation after Chantaleela administration according to the control for both male and female groups. The same results were also obtained in other subgroup analysis including hyperaggregation group, hypo-normal aggregation group. CONCLUSION: From the present study, normal dose of Chantaleela for alleviation of fever does not have an effect on either platelet aggregation or platelet numbers. It may conclude that the present study supports the safety use of Chantaleela for relieving fever as platelet status does not need to be taken into consideration.

Effects of selective COX-inhibitors and classical NSAIDs on endothelial cell proliferation and migration induced by human cholangiocarcinoma cell culture.

OBJECTIVE: Experiments were designed to explore cellular mechanisms and effects of NSAIDs on human umbilical vein endothelial cells (HUVEC) induced by human cholangiocarcinoma (HuCCA). MATERIAL AND METHOD: HUVEC were incubated with HuCCA or HuCCA-conditioned medium (CM) for various times to determine cell proliferation and migration. Expression of cyclooxygenase (COX) proteins was measured using immunoblotting technique. VSA (selective COX-1 inhibitor), NS-398 (selective COX-2 inhibitor), and aspirin were used as pharmacological tools to explore signaling mechanisms of HuCCA-CM-induced endothelial cell functions. RESULTS: HuCCA could significantly induce proliferation and migration of HUVEC. COX-2, but not COX-1, was increased. NS-398, but not VSA, could significantly inhibit HuCCA-CM-induced endothelial cell proliferation. HuCCA-CM-induced endothelial cell proliferations could be also inhibited by aspirin. CONCLUSION: These findings suggest that HuCCA-CM-derived substances could induce HUVEC proliferation through COX-2 signaling mechanism. Classical NSAID and selective COX-2 inhibitors could also inhibit this step of HUVEC proliferation.

The effects of estrone, estradiol and estriol on platelet aggregation induced by adrenaline and adenosine diphosphate.

The impact of estrogens on the cardiovascular system and their ability to regulate platelet functions remains controversial. Changes in platelet functions could contribute to thrombotic risk associated with estrogen treatments. Here, we investigated the effects of various forms of estrogen, including estrone (E1), estradiol (E2) and estriol (E3), on platelet aggregation induced by standard agonists (adrenaline and adenosine diphosphate). Platelet-rich plasma (PRP) was prepared from citrated blood donated by 25 normal volunteers. The study on platelet aggregation was carried out in 96-well flat-bottom microtitre plates and assessed using a microplate reader. For studying the effects of each estrogen, PRP was preincubated with 1, 10 and 100 nM of E1, E2 and E3 at 37 degrees C for 20 min, and then coincubated with normal saline (control untreated PRP), adrenaline (ADR) or adenosine diphosphate (ADP) in the microplate. Platelet aggregation was then measured every minute for 8 min. None of the estrogens (E1, E2 and E3) affected platelet aggregation in untreated PRP. Interestingly, only E1 and E3 can synergize the increased platelet aggregation by either ADR or ADP, while the effects of E2 on the increased platelet aggregation by either ADR or ADP depended on internal factors such as endogenous estradiol and platelet aggregated state. Thus, for the rational use of these internal factors for estrogen use, especially E2, in clinical applications, such as hormone replacement therapy, may need evaluation of thrombotic risk.

The expression of COX-2 in VEGF-treated endothelial cells is mediated through protein tyrosine kinase.

Cyclooxygenase (COX), existing as the COX-1 and COX-2 isoforms, converts arachidonic acid to prostaglandin H2, which is then further metabolized to various prostaglandins. Vascular endothelial growth factor (VEGF) has been shown to play important roles in inflammation and is upregulated by the prostaglandin E series through COX-2 in several cell types. Here, we have investigated the effects of VEGF on the COX isoform expressed in human umbilical vein endothelial cells (HUVEC). The signalling mechanism of the COX isoform expressed in endothelial cells activated with VEGF will be also investigated using the tyrosine kinase inhibitor, genistein, and protein kinase C inhibitor, staurosporine. The activity of COX-2 was assessed by measuring the production of 6-keto-prostaglandin F1alpha in the presence of exogenous arachidonic acids (10 microM, 10 min) by enzyme immunoassay. The expression of COX isoform protein was detected by immunoblot using specific antibodies. Untreated HUVEC contained no COX-2 protein. In HUVEC treated with VEGF (0.01-50 ng/ml), COX-2 protein, but not COX-1, and COX activity were increased in a dose-dependent manner. Interestingly, the increased COX-2 protein and activity in response to VEGF (10 ng/ml) was inhibited by the tyrosine kinase inhibitor, genistein (0.05-5 microg/ml), but not by the protein kinase C inhibitor, staurosporine (0.1-10 ng/ml). Thus, the induction of COX-2 by VEGF in endothelial cells was mediated through protein tyrosine kinase, and the uses of specific COX-2 inhibitors in these conditions, in which VEGF was involved, might have a role.