ABSTRACT
OBJECTIVE： To investigate in vitro release rate and in vivo pharmacokinetics of Resveratrol/hydroxypropyl-β- cyclodextrin/chitosan sustained-release pellets （RES/HP-β-CD/Chitosan） in rats. METHODS： In vitro release rate of RES raw materials， RES-HP-β-CD complexes （RES/HP-β-CD） and RES/HP-β-CD/Chitosan in water within 12 h were investigated by paddle method. The pharmacokinetic characteristics of RES raw materials， RES/HP-β-CD and RES/HP-β-CD/Chitosan were compared within 720 min after intragastric administration. RESULTS： Compared with RES raw materials， in vitro release rate of RES/HP-β-CD was increased significantly， and 120 min accumulative release rate reached 87％. Compared with RES/HP-β-CD， in vitro release rate of RES/HP-β-CD/Chitosan were relieved significantly； release time prolonged significantly； 12 h accumulative release rate was 72％. The pharmacokinetic parameters of RES raw materials， RES/HP-β-CD and RES/HP-β-CD/Chitosan included that cmax were 473.3， 2 492.2， 590.5 ng/mL； t1/2 were 2.6， 0.5， 4.6 h； AUC0-12 h were 514.7， 824.6， 2 778.5 ng·h/mL. Compared with RES raw materials， relative bioavailability of RES/HP-β-CD and RES/HP-β-CD/Chitosan were 172.5％ and 540.0％. CONCLUSIONS： RES/HP-β-CD/Chitosan shows good sustained-release effect， and its bioavailability is significantly higher than that of RES raw materials， RES/HP-β-CD.
ABSTRACT
OBJECTIVE： To prepare Resveratrol-hydroxypropyl-β-cyclodextrin-chitosan sustained-release pellets （RES-HP-β- CD-Chitosan）， and to characterize it. METHODS： Resveratrol raw material， HP-β-cyclodextrin and chitosan were collected with ratio of 1 ∶ 7 ∶ 0.25. Resveratrol-HP-β-cyclodextrin inclusion compound were prepared by solvent method， and then added into chitosan， RES-HP-β-CD-Chitosan were prepared by spray drying method. Particle size of prepared sustained-released pellets were observed by optical microscope. X-ray， DSC， IR and SEM were used to characterize RES-HP-β-CD-Chitosan. The contents of resveratrol in prepared sustained-released pellets were determined by UV spectrum， and drug-loading amount and encapsulation efficiency were calculated. RESULTS： Particle size of prepared RES-HP-β-CD-Chitosan was （2.23±0.35） μm （n＝300）. Characterization results show that RES-HP-β-CD-Chitosan was spherical in shape； shrinkage was found on the surface of microspheres， and resveratrol was included in HP-β-cyclodextrin in molecule or amorphous state. Drug-loading amount of prepared RES-HP-β-CD-Chitosan was 11.67％ （n＝3）， encapsulation efficiency was 96.27％ （n＝3）. CONCLUSIONS： RES-HP-β-CD- Chitosan is prepared successfully.
ABSTRACT
Objective To investigate the protective effect of Xinyi capsule pretreatment on myocardial ischemia reperfusion injury in rabbits and its possible mechanism. Methods Ninety-four rabbits were randomly divided into 6 groups: model group (n=16), tirofiban group (n=16), high-, medium- and low-dose Xinyi capsule groups (4.0, 2.0, 1.0 g/kg;n=16 in each group), and sham operation group (n=14). Five days after intragastric administration with drug, myocardial ischemia reperfusion was induced by ligation of the proximal left circumflex artery. The electrocardiogram (ECG) was continuously recorded. The serum levels of myeloperoxidase (MPO), lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) were measured. Myocardial histopathological damage was evaluated. Results The changes of J-point amplitude on ECG in high-, medium-and low-dose Xinyi capsule groups (0.064 ± 0.049 mV, 0.069 ± 0.061 mV, 0.079 ± 0.060 mV) were significantly lower than that in the model group (0.158 ± 0.105 mV, P<0.01 or P<0.05), the serum levels of LDH (399.7 ± 202.3 U/L, 369.6 ± 229.0 U/L, 435.5 ± 152.4 U/L), CK-MB (900.8 ± 231.2 U/L, 1 268.3 ± 899.8 U/L, 1 386.7 ± 621.6 U/L), MPO (69.81 ± 5.51 U/L, 85.44 ± 10.31 U/L, 81.33 ± 16.87 U/L) were significantly lower than those in the model group (LDH:817.1 ± 401.9 U/L, CK-MB:2 071.3 ± 693.5 U/L, MPO:149.9 ± 20.11 U/L;P<0.01 or P<0.05). Histopathological examination showed that myocardial damage in high-, medium- and low-dose Xinyi capsule groups reduced compared with the model group. Conclusions Xinyi capsule pretreatment can protect against myocardial ischemia reperfusion injury in rabbits, and its mechanism may be related to inflammation inhibition.