Borneol enhances the protective effect against cerebral ischemia/reperfusion injury by promoting the access of astragaloside IV and the components of Panax notoginseng saponins into the brain.

Astragalus and Panax notoginseng are significant traditional Chinese medicines for treating ischemic stroke, with astragaloside IV (AST IV) and Panax notoginseng saponins (PNS) being the major effective compounds, respectively. These compounds can also be used in combination. We have previously shown that AST IV and PNS have an antagonistic effect on cerebral ischemia/reperfusion (I/R) injury, and the combination of these two drugs can elevate this effect; unfortunately, AST IV and PNS cannot easily enter the brain tissues through the blood brain barrier (BBB). Previous studies have confirmed that the combination of borneol with other agents could promote the penetration of the drug components through the BBB. However, it remains unclear whether borneol can promote entry of the active components of AST IV and PNS into the brain tissues and enhance their effect against cerebral ischemia. This study aimed to investigate the effects of a combination of borneol with AST IV and PNS against I/R injury and explore the mechanisms of borneol-promoting penetration of drug components into the BBB based on the drug transport of brain tissues. A rat model of focal cerebral I/R injury was established, and drugs, including borneol, AST IV, and PNS, as well as their combinations were intragastrically administered. Subsequently, drug efficacy was assessed, and the condition of AST IV and PNS active components (Rg1, Rb1, R1) delivered into the brain was analyzed. Moreover, BBB permeability was determined, and the expression of related drug transporters and their genes were evaluated. After treatment with borneol, AST IV, PNS, AST Ⅳ+PNS, and borneol+AST Ⅳ+PNS after cerebral I/R, the neurological function deficit scores, cerebral infarct rate, and brain water content markedly decreased. The effects of the three-drug-combination were better than those of the drugs used alone and those of AST Ⅳ+PNS. Moreover, after I/R in rats, AST IV and the components of PNS (Rg1, Rb1, R1) were mainly found in the cerebral cortex and in the cerebellum, respectively, when used alone. Borneol combined with AST IV and PNS increased the contents of AST IV, Rb1, Rg1, and R1 in the cerebral cortex and in the cerebellum, thus, promoting the enrichment of active components to the cerebral cortex, especially to the affected side. In addition, following I/R, diffuse distribution of lanthanum particles in the basement membrane, intercellular and intracellular locations of rat brain tissues indicated BBB destruction and increase in permeability, which were alleviated in each drug group. The effects of borneol combined with AST IV and PNS were stronger than those of the drug single-used and those of the AST IV+PNS group. Finally, the expression of effluent transporters (ET) and their genes, including P-glycoprotein (P-gp), multidrug resistance protein (MRP)-1, MRP-2, MRP-4, and MRP-5 in brain tissues, strikingly increased after I/R. Borneol remarkedly down-regulated the protein expression of P-gp, MRP-2, and MRP-4 in the brain, whereas PNS down-regulated MRP-4 and MRP-5 protein expression. AST IV, AST IV+PNS, and bornoel+AST IV+PNS effectively decreased the expression of P-gp, MRP-2, MRP-4, and MRP-5 proteins. The effects of the three-drug combination were significantly greater than those of the drug single-used and AST IV+PNS groups. The expression of each ET gene manifested corresponding results. Meanwhile, PNS, AST IV+PNS, and bornoel+AST IV+PNS significantly inhibited the down-regulation of the uptake transporter organic anion transporting polypeptide (OATP)-2 expression, and the effect of bornoel+AST IV+PNS was stronger than that of other groups. After I/R, the brain tissues were injured, BBB permeability increased, expression of critical ET and their genes were markedly up-regulated, and the main uptake transporters were down-regulated. We propose that the combination of borneol, AST IV and PNS could enhance the effect against cerebral I/R injury and protect BBB integrity. The potential mechanism might be the delivery of AST IV and active components of PNS to the brain tissues after treatment in combination with borneol, which could be effectively promoted by down-regulating the expression of ETs and up-regulating the expression of uptake transporters in the brain tissues. This study was the first to demonstrate that borneol combined with AST IV+PNS enhanced the effect against cerebral I/R injury through promoting the entry of AST and PNS active components to the brain tissues. Thus, this study proposes an instructive role in developing effective active ingredients combination of Chinese medicine with clear ingredients and synergistic effects in terms of the characteristic of borneol.

Zhu QY ，Tang S ，Yang XQ ，Ding H ，Liu XD ，Zeng XB ，Huang XP ，Deng CQ ... -  《-》

Effects of the Combination of the Main Active Components of Astragalus and Panax notoginseng on Inflammation and Apoptosis of Nerve Cell after Cerebral Ischemia-Reperfusion.

Huang XP ，Ding H ，Lu JD ，Tang YH ，Deng BX ，Deng CQ ... -  《-》

[Mechanism of astragaloside Ⅳ combined with Panax notoginseng saponins in regulating angiogenesis to treat cerebral ischemia based on network pharmacology and experimental verification].

Li YL ，Lu ZH ，Zhang YY ，Wu SS ，Xie TH ，Ding H ，Zhang W ，Liu XD ，Deng CQ ... -  《-》

[Effect of astragaloside Ⅳ combined with Panax notoginseng saponins on cerebral ischemia-reperfusion injury and study of pharmacokinetics in rats].

The aim is to study the effect of astragaloside Ⅳ (AST Ⅳ) combined with Panax notoginseng saponins (PNS) on cerebral ischemia-reperfusion injury, and to probe the synergistic mechanism through the pharmacokinetics of the four major components such as AST Ⅳ, ginsenoside Rg₁ (Rg₁), ginsenoside Rb₁ (Rb₁), notoginsenoside R₁ (R₁) in cerebral ischemia-reperfusion rats. Following the establishment of cerebral ischemia/reperfusion model in rats by modified suture method, neurological function score, cerebral infarction area and pathomorphology were used to evaluate the pharmacological effect that the combination of AST Ⅳ and PNS antagonized cerebral ischemia-reperfusion injury; the contents of AST Ⅳ, Rg₁, Rb₁, R₁ in rat plasma of different time points were determined with ultra performance liquid chromatography tandem massspectrometry (UPLC-MS/MS), pharmacokinetic parameters were calculated and pharmacokinetics changes of the main effective components were analyzed. The results showed that AST Ⅳ, PNS alone and their combination could reduce the cerebral infarction area of rats, relieve the behavioral scores of neurologic deficit, improve the pathological changes after cerebral ischemia, the effects of the combination were better. Among AST Ⅳ, Rg₁, Rb₁, R₁, the area under the curve (AUC) was significantly increased, the mean residence time of (MRT0-t) was delayed, the peak concentration (Cmax) was significantly raised, the apparent volume of distribution (Vz/F) was reduced, and the clearance rate in vivo was significantly slowed. It suggested that AST Ⅳ combined with PNS has synergistic enhancement on anti-cerebral ischemia/reperfusion injury, moreover, make the pharmacokinetic behavior of the main effective components change, the mechanism may be associated with prolonging the retention time of the effective components in cerebral ischemia condition, elevating the bioavailability.

Li JX ，Yang XQ ，Tang B ，Liu XD ，Tang YH ，Deng CQ ，Huang XP ... -  《-》

Effects of the main active components combinations of Astragalus and Panax notoginseng on energy metabolism in brain tissues after cerebral ischemia-reperfusion in mice.

Huang XP ，Ding H ，Wang B ，Qiu YY ，Tang YH ，Zeng R ，Deng CQ ... -  《-》