Comparative analysis of the neuroprotective effects of ginsenosides Rg1 and Rb1 extracted fromPanax notoginsengagainst cerebral ischemia

Abstract

Panax notoginseng, a traditional Chinese medicine, has been used for thousands of years to treat ischemic patients. More than 20 saponin components have been isolated from P. notoginseng root and identified chemically. However, these different chemical components have different roles. In this study we compared the neuroprotective mechanisms of ginsenosides Rg1, Rb1, Rg1/Rb1, and panax notoginsenoside (PNS) against injuries caused by cerebral ischemia-reperfusion (I/R). Our results show that all of these treatments significantly reduced infarction volume and alleviated neurological deficits caused by cerebral I/R. The increase in malondialdehyde (MDA) concentration was inhibited by these treatments in the hippocampus. The decreased expressions of thioredoxin-1 (Trx-1), copper-zinc superoxide dismutase (SOD-1), protein kinase B (PKB/Akt), and nuclear factor-kappa B (NF-κB) caused by cerebral I/R were restored by these treatments. The expression of heat shock protein 70 (HSP70) was enhanced in the middle cerebral artery occlusion (MCAO) group, as well as in all of the treatment groups. These results suggest that Rg1 and Rb1 have similar roles in protecting the brain from ischemic damage; however, neither Rg1/Rb1 nor PNS have synergistic effects, thus either Rg1 or the Rb1 monomer should be considered as a pharmacological neuroprotective strategy for use in the case of ischemic stroke.

<b><i>Panax notoginseng</i></b> Saponins Ameliorate Leukocyte Adherence and Cerebrovascular Endothelial Barrier Breakdown upon Ischemia-Reperfusion in Mice

“…In the tMCAO mice model, we demonstrated that PNS effectively lead to a decrease in the infarct volume, histological damage, and neurological deficits after I/R, which contradicted previous studies [11, 12]. In addition, we revealed, in quite a direct way, that PNS alleviated the microvascular disturbances, including leukocyte adhesion and albumin leakage.…”

“…I/R injury was inflicted through transient middle cerebral artery occlusion (tMCAO), which has been widely used in previous studies [11, 12]. Mice were separated into four groups: the Sham group, ischemia/reperfusion group (I/R), PNS 45 mg/kg group (I/R + PNS 45), and PNS 22.5 mg/kg group (I/R + PNS 22.5).…”

“…Emerging data show that PNS and its constituents have anti-inflammatory [10, 11], anti-oxidant [12, 13], and anti-apoptotic properties [13, 14] in both global and focal ischemic cerebrovascular disease. However, it is not clear whether PNS have a protective impact on the restoration of microvascular dyshomeostasis, which is essential to tissue survival after I/R.…”

Panax notoginseng saponins provide neuroprotection by regulating NgR1/RhoA/ROCK2 pathway expression, in vitro and in vivo

“…The traditional Chines medicine PNS has been clinically applied as a therapy for cerebrovascular diseases because of its ability to suppress cerebral thrombosis and reduce blood viscosity (Zeng et al, 2014). PNS also exerts neuroprotective effects against CNS ischemia/reperfusion (I/R) injury by reducing inflammation and apoptosis (Ning et al, 2012), as well edema and infarct volume .…”

The expression of thioredoxin-1 in acute epinephrine stressed mice

“…Trx-1 has various biological activities and is upregulated in response to a wide variety of stresses, including viral infections and ultraviolet and X-ray irradiation (Masutani et al 2004). Our previous findings showed that Trx-1 played neuroprotective roles in oxidative stress, neurodegenerative disorders, cerebral ischemia, chronic stress, and morphine addiction (Jia et al 2014;Luo et al 2013;Zeng et al 2014a;Zeng et al 2015;Zeng et al 2014b). However, it is unclear whether Trx-1 is involved in acute stress.…”