Preparation, Characterization and in vivo Study of Borneol-Baicalin-Liposomes for Treatment of Cerebral Ischemia-Reperfusion Injury.

PURPOSE: Baicalin (BA) has a good neuroprotective effect, but it is eliminated quickly in the body and does not easily reach the brain. In this experiment, borneol (BO) was used as an auxiliary drug to prepare borneol-baicalin-liposomes (BO-BA-LP) to prolong the efficacy time of BA, synergistically synergize, introduce drugs into the brain, and better exert the therapeutic effect on cerebral ischemia-reperfusion (I/R) injury. METHODS: Through single-factor inspection and response surface optimization analysis, obtained the best preparation process of BO-BA-LP and characterized by various analytical techniques. Validated the long-term effectiveness of BA-BO-LP through pharmacokinetic studies and conducted pharmacodynamic studies on the middle cerebral artery occlusion (MCAO) rat model to verify the therapeutic effect of BO-BA-LP on cerebral I/R injury. RESULTS: The optimum preparation conditions of BO-BA-LP were as follows: the dosage of BO was 9.55 mg, the ratio of phospholipid to drug was 4.02:1, the ratio of phospholipid to cholesterol was 7.25:1, the entrapment efficiency (EE) was 41.49%, and the drug loading (DL) was 4.29%. The particle size range of the liposomes was 167.1 nm, and the polydispersity index (PDI) range was 0.113. The results of pharmacokinetic experiments showed that the combination of BA and BO liposomes effectively improved the pharmacokinetic parameters of BA and prolonged the half-life of BA. Pharmacodynamic studies have found that, compared with BA-LP, BO-BA-LP can significantly improve neurological deficits, cerebral infarction volume, and brain pathological states on MCAO rats. CONCLUSION: These results demonstrated that BO-BA-LP can improve the circulation of drugs in the blood, and the addition of BO can enhance the therapeutic effect of BA and effectively improve cerebral I/R.

Anti-melanogenesis of novel kojic acid derivatives in B16F10 cells and zebrafish.

Novel kojic acid derivatives (KADs) with the potential ability to inhibit tyrosinase were synthesized and were further identified by Q-Exactive, IR and NMR. Among these compounds, KAD2 showed the best inhibitory effects on diphenolase activity and monophenolase activity, with IC50 of 7.50 µM and 20.51 µM, respectively. The anti-melanogenic activity of KAD2 was further confirmed by assessing the inhibition of melanin content and intracellular tyrosinase activity in B16F10 cells and zebrafish model. It demonstrated that KAD2 suppressed the expression of microphthalmia-associated transcription factor (MITF), tyrosinase (TYR), tyrosinase related protein-1 and 2 (TRP-1 and TRP-2) in a concentration-dependent manner. Furthermore, KAD2 dose-dependently suppressed the expression of the phosphorylation of protein kinase A (PKA) and cAMP-response element binding protein (CREB) and rescued the phosphorylation of Akt. Additionally, KAD2 could inhibit body pigmentation in zebrafish. Taken together, our findings elucidated that KAD2 has significant anti-melanogenic activity via CREB and Akt pathway-mediated suppression the expression of MITF and TYR family proteins in B16F10 cells. It could provide new insight into the development of novel anti-melanogenic agents to apply in the fields of food sciences, agriculture, cosmetics and medicine.