Evolution of congenital haemophilia care in Taiwan.

Haemophilia care in Taiwan has come a long way over the past 35 years, from the absence of specialised haemophilia treatment centres before 1984 to the establishment of treatment centers in the majority of medical centers, the listing of haemophilia as a catastrophic illness with full treatment reimbursement by the Taiwan National Health Insurance (NHI), and the implementation of full NHI coverage for prophylaxis therapy. This has led to outcome improvements such as reduced bleed-related morbidity and mortality, fewer viral infections, and enhanced overall multi-modality care. Most people with haemophilia (PWH) are now able to live normal, active lives. Early diagnosis has improved through increased awareness, physician education, and prenatal diagnosis; while comprehensive care, including state of the art rehabilitation and orthopaedic management for haemophilic arthropathy, eradication therapy for chronic hepatitis C, and better treatments for human immunodeficiency virus, allows PWH to enjoy a better quality of life and improved survival. Efforts are now being made to raise prophylaxis rates through full NHI reimbursement and the use of extended half-life recombinant factor products. Overall, Taiwan has made great strides in haemophilia care and we would like to share these experiences for the benefit of all healthcare providers involved in haemophilia care.

Stereoselectivity evaluation of chiral chitosan microspheres delivery system containing rac-KET in vitro and in vivo.

The influence of chiral excipient D-chitosan (CS) on the stereoselective release of racemic ketoprofen (rac-KET) microspheres has been investigated in comparison to those microspheres containing individual enantiomers in vitro and in vivo. Stereoselectivity was observed in vitro release test, with R-KET release slightly higher than that of S-KET, especially in 3% rac-KET loading microspheres. Stereoselectivity is dependent on the content of chiral excipient and pH of release medium. A molecular docking study between CS and KET enantiomers further revealed that S-KET has a stronger interaction with CS compared to R-KET. Moreover, the plasma concentration of KET enantiomers in rats shows substantial differences, as the plasma levels of S-KET were higher than those of R-KET. Plasma levels of enantiomers from the R-KET microspheres had similar stereoselectivity as rac-KET microspheres. The S/R ratio of rac-KET microspheres was significantly lower than that of rac-KET suspension (regular-release formulation) (p<.05), and the differences is 3-5 fold. Besides, rates of R-KET converted to S-KET exhibited differences between rac-KET microspheres and suspension. Similar results were also found between R-KET microspheres and suspension. All investigations suggest that the chitosan interacting preferentially with S-KET to R-KET significantly affect the stereoselective pharmacokinetics of rac-KET from chitosan microspheres in rats.

[Oral absorption of asiatic acid nanoparticles modified with PEG].

A solvent diffusion method was used to prepare pegylated asiatic acid (AA) loaded nanostructured lipid carriers (p-AA-NLC), and the ligated intestinal circulation model was established to observe the absorption and distribution in small intestine. The concentration of AA in bile after oral administration of p-AA-NLC was detected by HPLC in healthy SD rats to indirectly evaluate the oral absorption promoting effect of PEG-modified namoparticles. The results showed that the penetration of p-AA-NLC was enhanced significantly and the transport capacity was increased greatly in small intestinal after PEG modification. As compared with the normal nanoparticles (AA-NLC), the Cmax of the drug excretion was increased by 76%, the time to reach the peak (tmax ) was decreased and the elimination half-life t1/2 was doubled in the rats after oral administration of p-AA-NLC, and the AUC0→t was 1.5 times of the AA-NLC group, indicating that the oral bioavailability of AA-NLC was significantly improved by hydrophilic modification of PEG.

[Response surface method for optimization of asiatic acid nanoparticles modified with PEG and its enhancing effects on intestinal absorption].

A solvent diffusion method was used to prepare pegylated asiatic acid (AA) loaded nanostructured lipid carriers (p-AA-NLC). Then central composite design-response surface method was used to obtain optimum condition for preparation technology of p-AA-NLC, where PEG/lipid ratio was 8.0% and AA/lipid ratio was 22.0%. Under the optimum condition, the system had particle size of (111.2±2.9) nm, Zeta potential of (-37.1±0.9) mV, drug loading of (15.4±0.2)% and entrapment efficiency greater than 90%. The deviations between observed values and predicated values were all below 5%, indicating that the established model had a good predictability. Meanwhile, a low-speed single pass perfusion model of rat in situ was set up to estimate the absorption kinetics of p-AA-NLC in small intestine, where the effective permeability (Peff), absorption rate constant (Ka) and other parameters were used to evaluate the drug absorption. It turned out that Peff and Ka in p-AA-NLC group were significantly higher than those in unmodified group (P<0.05), indicating that asiatic acid loaded nanostructured lipid carriers (AA-NLC) could enhance the effects on intestinal absorption after being modified with hydrophilic PEG.

Evodiamine Induces Transient Receptor Potential Vanilloid-1-Mediated Protective Autophagy in U87-MG Astrocytes.

Cerebral ischemia is a leading cause of mortality and morbidity worldwide, which results in cognitive and motor dysfunction, neurodegenerative diseases, and death. Evodiamine (Evo) is extracted from Evodia rutaecarpa Bentham, a plant widely used in Chinese herbal medicine, which possesses variable biological abilities, such as anticancer, anti-inflammation, antiobesity, anti-Alzheimer's disease, antimetastatic, antianoxic, and antinociceptive functions. But the effect of Evo on ischemic stroke is unclear. Increasing data suggest that activation of autophagy, an adaptive response to environmental stresses, could protect neurons from ischemia-induced cell death. In this study, we found that Evo induced autophagy in U87-MG astrocytes. A scavenger of extracellular calcium and an antagonist of transient receptor potential vanilloid-1 (TRPV-1) decreased the percentage of autophagy accompanied by an increase in apoptosis, suggesting that Evo may induce calcium-mediated protective autophagy resulting from an influx of extracellular calcium. The same phenomena were also confirmed by a small interfering RNA technique to knock down the expression of TRPV1. Finally, Evo-induced c-Jun N-terminal kinases (JNK) activation was reduced by a TRPV1 antagonist, indicating that Evo-induced autophagy may occur through a calcium/c-Jun N-terminal kinase (JNK) pathway. Collectively, Evo induced an influx of extracellular calcium, which led to JNK-mediated protective autophagy, and this provides a new option for ischemic stroke treatment.

Determination of asiatic acid in beagle dog plasma after oral administration of Centella asiatica extract by precolumn derivatization RP-HPLC.

A novel precolumn derivatization reversed-phase high-performance liquid chromatography (RP-HPLC) method with UV-vis detection for the quantitative determination of total concentration of asiatic acid (AA) in beagle dog plasma is described. AA was extracted with n-hexane-dichloromethane-2-propanol (20:10:1, v/v/v) from plasma, which had been hydrolyzed by acid and derivatized with p-Toluidine. Chromatographic separation was achieved on a C(18) column using gradient elution in a water-methanol system. Detection was set at UV wavelength of 248nm. A calibration curve ranging from 0.01 to 1.5microg/mL was shown to be linear, and the lower limit of quantification (LLOQ) was 0.01microg/mL. The intra- and inter-day precisions which were determined by three different concentrations (0.05, 0.2 and 0.8microg/mL) ranged from 4.4% to 13.1% and 4.6% to 14.2%, respectively. Mean extraction recoveries were no less than 65% for AA and ursolic acid (IS). Plasma samples containing asiatic acid were stable for 30 days at -20 degrees C. The method was successfully applied to a pharmacokinetic study in beagle dogs after oral administration of Centella asiatica extract, and the main pharmacokinetic parameters obtained were: T(1/2), 4.29h; T(max), 2.70h; C(max), 0.74microg/mL; AUC(0-t) and AUC(0-infinity), 3.74 and 3.82microgh/mL, respectively.

Mechanisms of suppression of nitric oxide production by 3-O-methylquercetin in RAW 264.7 cells.

Rhamnus nakaharai Hayata (Rhamnaceae) is used as a folk medicine in Taiwan for treating constipation, inflammation, tumors, and asthma. 3-O-Methylquercetin (3-MQ), a main constituent of the plant, has been reported to have potential for use in the treatment of asthma. The mechanisms of anti-inflammation of 3-MQ are still unclear. Nitric oxide (NO) production induced by lipopolysaccharide (LPS) through iNOS expression in RAW 264.7 cells, a mouse macrophage cell line, may reflect the degree of inflammation and may provide a measure for assessing the effect of drugs on the inflammatory process. Therefore, we were interested in investigating the mechanisms of suppression of NO production by 3-MQ in RAW 264.7 cells. 3-MQ (1-10 microM) concentration-dependently inhibited LPS (100 ng/mL)-induced NO production in RAW 264.7 cells. The IC(50) value was calculated to be 4.23 microM. 3-MQ (1-10 microM) significantly and concentration-dependently inhibited LPS (100 ng/mL)-induced iNOS protein and mRNA expressions in cells. The IC(50) values were calculated to be 4.36 and 6.53 microM, respectively. There was no significant difference among these three IC(50) values of 3-MQ. In conclusion, 3-MQ may exert its anti-inflammatory effect through the inhibition of iNOS DNA transcription.

3-O-methylquercetin more selectively inhibits phosphodiesterase subtype 3.

Rhamnus nakaharai Hayata (Rhamnaceae), has been used as a folk medicine in Taiwan for treating constipation, inflammation, tumors and asthma. 3-O-methylquercetin (3-MQ), a main constituent of the plant, has been reported to inhibit total cAMP- and cGMP-phosphodiesterase (PDE) of guinea pig trachealis. Therefore we were interested in investigating the inhibitory effect of 3-MQ on various PDE isozymes from guinea pig lungs and hearts. Isolated guinea pig lungs and hearts were homogenized and centrifuged. The supernatant was chromatographed over a column of Q-sepharose, and eluted with various concentrations of NaCl. In the following order, PDE subtypes 1, 5, 2, 4 from lungs, and 3 from hearts were separated. The IC 50 values of 3-MQ on these isozymes were 31.9, 86.9, 18.6, 28.5 and 1.6 microM, respectively. 3-MQ (10-100 microM) non-competitively inhibited PDE2, but competitively inhibited PDE4. 3-MQ (1-10 microM) also competitively inhibited PDE3. However, 3-MQ (10-100 microM) did not competitively inhibit PDE1 and 5, although it had a tendency to competitively inhibit PDE1 at concentrations of 10 - 30 microM. The present results showed that K i value of 3-MQ was similar to that of milrinone in PDE3, and was not significantly different from that of Ro 20 - 1724 in PDE4, respectively. In conclusion, 3-MQ was revealed to be a selective and competitive PDE3/PDE4 inhibitor, although its inhibitory effect on PDE4 was not potent. Therefore, 3-MQ may have a potential in the treatment of asthma beside its antiviral activity.

S-Isopetasin, a sesquiterpene of Petasites formosanus, allosterically antagonized carbachol in isolated guinea pig atria.

We investigated the antimuscarinic effect of S-isopetasin in isolated guinea pig atria to clarify whether it preferentially acts on muscarinic M 2 or M 3 receptors. The tension changes of isolated atria were isometrically recorded on a polygraph. S-Isopetasin at 50 and 100 microM significantly inhibited baselines of contractile tension and heart rate, but atropine at 1 microM enhanced both. S-Isopetasin (10 - 100 microM) did not significantly alter the concentration-negative inotropic response curves of carbachol (CCh) in left atria. S-Isopetasin (10 - 100 microM) allosterically antagonized negative inotropic and chronotropic responses induced by CCh in spontaneously beating right atria, based on the slopes of Schild plots significantly differing from unity. On the contrary, atropine (0.01 - 1 microM) competitively antagonized all the above responses to CCh. The pA 2 values of S-isopetasin were significantly less than that of S-isopetasin in guinea pig trachealis, suggesting that S-isopetasin may preferentially act on tracheal muscarinic M 3, but not cardiac muscarinic M 2 receptors. However, atropine preferentially acts neither. This finding reveals that S-isopetasin may have benefit in the treatment of asthma.