Gut microbiota-mediated metabolism of Panax notoginseng saponins and its role in pharmacokinetics and pharmacodynamics

Panax notoginseng saponins(PNS)are a class of effective ingredients in Notoginseng Radix et Rhizoma,a well-known herbal medicine called San-Qi in Chinese.After oral administration,PNS inevitably interacts with gut microbiota,and thus affect the pharmacokinetic profiles and pharmacological effects.To date,studies concering gut microbiota-mediated metabolism of PNS have not been reviewed systematically.Herein,we outline the metabolic profiles of Panax notoginseng saponins mediated by gut microbiota,as well as its role in the pharmacokinetics and pharmacodynamics on the basis of reported data.The metabolic pathways of primary saponins are proposed,and step-by-step deglycosylation is found to be the primary degradation pathways of PNS mediated by gut microbiota.Specific microorganisms and enzymes involved in the metabolic processes were summarized.Gut microbiota is deeply involved in the metabolism of PNS,affects the pharmacokinetic profiles,and produces a series of active metabolites.These metabolites were documented to play an essential role in the efficacy of the parent compounds.Future studies should focus on strengthening the real-world evidence,defining the interaction between gut microbiota and PNS,and developing the strategy for modulating gut microbiota to enhance the bioavailability and efficacy of PNS.These information would be useful for further research and clinical application of PNS.

Panax notoginseng saponin attenuates hypoxia/reoxygenation-induced oxidative stress in cortical neurons

The present study monitored the effect of 2, 10, and 50 mg/L of Panax notoginseng saponin exposure following hypoxia-reoxygenation injury in fetal rat cortical neurons. Results showed that varying doses of Panax notoginseng saponin significantly enhanced the cell viability of neurons, reduced malondialdehyde content, increased superoxide dismutase activity, inhibited mRNA and protein expression of inducible and neuronal nitric oxide synthase, and decreased the release of nitric oxide in hypoxia/reoxygenation injured cells. In particular, 50 mg/L of Panax notoginseng saponin was the most effective dose. These findings suggest that Panax notoginseng saponin can attenuate neuronal oxidative stress injury caused by hypoxia/reoxygenation in a dose-dependent manner.

Effect of Panax notoginseng saponins on the expression of beta-amyloid protein in the cortex of the parietal lobe and hippocampus, and spatial learning and memory in a mouse model of senile dementia

BACKGROUND： The pharmacological actions of Panax notoginseng saponins （PNS） lie in removing free radicals, anti-inflammation and anti-oxygenation. It can also improve memory and behavior in rat models of Alzheimer＇s disease. OBJECTIVE： Using the Morris water maze, immunohistochemistry, real-time PCR and RT-PCR, this study aimed to measure improvement in spatial learning, memory, expression of amyloid precursor protein （App） and β -amyloid （A β ）, to investigate the mechanism of action of PNS in the treatment of AD in the senescence accelerated mouse-prone 8 （SAMP8） and compare the effects with huperzine A. DESIGN, TIME AND SETTING： A completely randomized grouping design, controlled animal experiment was performed in the Center for Research ＆ Development of New Drugs, Guangxi Traditional Chinese Medical University from July 2005 to April 2007. MATERIALS： Sixty male SAMP8 mice, aged 3 months, purchased from Tianjin Chinese Traditional Medical University of China, were divided into four groups： PNS high-dosage group, PNS low-dosage group, huperzine A group and control group. PNS was provided by Weihe Pharmaceutical Co., Ltd. （batch No.： Z53021485, Yuxi, Yunan Province, China）. Huperzine A was provided by Zhenyuan Pharmaceutical Co., Ltd. （batch No.： 20040801, Zhejiang, China）. METHODS： The high-dosage group and low-dosage group were treated with 93.50 and 23.38 mg/kg PNS respectively per day and the huperzine A group was treated with 0.038 6 mg/kg huperzine A per day, all by intragastric administration, for 8 consecutive weeks. The same volume of double distilled water was given to the control group. MAIN OUTCOME MEASURES： After drug administration, learning and memory abilities were assessed by place navigation and spatial probe tests. The recording indices consisted of escape latency （time-to-platform）, and the percentage of swimming time spent in each quadrant. The number of A β 1-40, A β 1-42 and App immunopositive neurons in the brains of SAMP8 mice was analyzed by immunohistochemistry. The mRNA content ofApp, tau, acetylcholinesterase, and synaptophysin （Syp） was tested by real time PCR and RT-PCR. RESULTS： The PCR results show that PNS can downregulate the expression of the App gene and upregulate the expression of the Syp gene in the parietal cortex and hippocampus of SAMP8 mice. The therapeutic effects of the PNS high-dosage group were greater than those of the PNS low-dosage group and the huperzine A group （P 〈 0.05）. The results of the Morris water maze and immunohistochemistry indicated that PNS can improve the capacity for spatial learning and memory in SAMP8 mice, and reduce the content of A β 1-40, A β 1-42 and expression of App in the brains of SAMP8 mice. The therapeutic effects of the PNS high-dosage group were greater than that of the PNS low-dosage group and the huperzine A group （P 〈 0.05）. CONCLUSION： These results support the hypothesis that PNS plays a therapeutic and protective role on the pathological lesions and learning dysfunction of Alzheimer＇s disease. The therapeutic effects of PNS for Alzheimer＇s disease are possibly achieved through downregulating the expression of the App gene and upregulating the expression of the Syp gene. The therapeutic effects of PNS are dose-dependent and are greater than the effect of huperzine A.

Panax notoginseng saponins preconditioning protects rat liver grafts from ischemia/reper- fusion injury via an antiapoptotic pathway

BACKGROUND: Ischemia/reperfusion (I/R) injury is a major cause of primary graft dysfunction and renders an al- lograft more immunogenic in orthotopic liver transplanta- tion (OLT). Panax notoginseng saponins (PNS) has been re- ported to exert protective effects against I/R injury to vari- ous organs. The objective of this study is to investigate whether PNS preconditioning protects rat liver grafts from I/R injury via an antiapoptotic pathway. METHODS: Male Sprague-Dawley rats were used as donors and recipients of orthotopic liver transplantation ( OLT) and were divided into PNS preconditioning group (group P) and normal saline control group (group N) randomly according to whether PNS (50 mg/kg) was injected intra- venously 1 hour before liver grafts harvesting, and sham group (group S). The animals were separately killed 2, 6 and 24 hours after reperfusion. Plasma samples were collect- ed for test of alanine amino-transferase (ALT) and aspartate aminotransferase (AST). Liver tissues were collected to de- tect histological changes, apoptosis and the expression of TNF-α, Bcl-2 and Caspase-3 mRNA. RESULTS: The serum levels of ALT and AST and the apop- tosis index (AI) of liver tissue in group P were lower than in group N significantly 2, 6 and 24 hours after reperfusion. Compared with group N, the expression of TNF-a and Caspase-3 mRNA was reduced significantly in group P 2 and 6 hours after reperfusion and the expression of Bcl-2 mRNA was enhanced significantly in group P 6 and 24 hours after reperfusion. CONCLUSIONS: PNS preconditioning protects liver grafts from I/R injury effectively in rat OLT via an antiapoptotic pathway. The antiapoptotic mechanisms of PNS may in- clude inhibiting the expression of TNF-a and Caspase-3 and enhancing the expression of Bcl-2.

Effects of Panax notoginseng saponins in a rat model of Alzheimer's disease

BACKGROUND： Modem pharmacological studies have demonstrated that Panax notoginseng saponins （PNS） can ameliorate and protect from neuropathological impairment. Whether PNS can improve the abnormality in memory and behavior of rats with Alzheimer＇s disease （AD） remains unclear. OBJECTIVE： Based on a Morris water maze test, this study aimed to measure improvements of spatial learning and memory by PNS in a rat model of AD, and to compare effects with huperzine A. DESIGN： A completely randomized grouping design, controlled animal experiment. SETTING： Center of Research ＆ Development of New Drugs, Guangxi Traditional Chinese Medical University. MATERIALS： Ninety healthy Wistar rats of both genders, 15-month-old （n =75） and 3-month-old rats as young controls （n =15）, were used for this study. The study was performed in accordance with animal ethics guidelines for the use and care of animals. PNS was provided by Weihe Pharmaceutical Co., Ltd （permission No. Z53021485, Yuxi, Yunan Province, China）. Morris water maze equipment was provided by the Institute of Physiology, Chinese Academy of Science. METHODS： This study was performed at the Center of Research ＆ Development of New Drugs, Guangxi Traditional Chinese Medical University from June 2003 to April 2005. Of the included rats, 15 healthy aged rats were randomly chosen as aged controls, and the remaining 60 aged rats were randomly divided into 4 groups with 15 rats in each： model group, PNS high- and low-dose groups, and an huperzine A group. Rats in the model group and the 3 treated groups were treated with intraperitoneal infusion of 9.6 g/L D-galactose （5 mL/kg） every day for 6 weeks successively to induce a subacute aging model. During week 7, animals received 1 μ L ibotenic acid （5 g/L） bilaterally into the nucleus basalis of Meynert to create a rat model of AD. The young and old rat controls received, in parallel, a corresponding volume of saline. Two weeks later, rats in the PNS high- and low-dose groups were gavaged with 200 and 100 mg/kg PNS suspension, respectively. Huperzine A suspension （0.3 mg/kg） was used in the huperzine A group. Rats in the other 3 groups were gavaged with a corresponding volume of normal saline. In each group, administration was carried out once per day for 4 consecutive weeks. MAIN OUTCOME MEASURES： After administration, learning and memory abilities were measured by place navigation and spatial probe tests. Recording indices consisted of escape latency （time-to-platform）, number of times to find the platform within 2 minutes, number of times the animal crosses the original platform location, and the percent of swimming time in each quadrant. RESULTS： Several rats died due to inflammatory reactions following brain lesion or intragastric administration; therefore, 61 rats were included in the final analysis. Results of spatial navigation test： Escape latency of rats in the model group was significantly prolonged, and number of times to find the platform within 2 minutes were significantly reduced compared with other groups （both P 〈 0.05）. No significant differences in these two indices were measured among the administration groups （all P 〉 0.05）. Results of spatial probe test： Times for crossing the original platform location and percent of time spent in the quadrant of original platform location were significantly less in the model group than in the other groups （P 〈 0.05）. There were no significant differences in these two indices among the administration groups （P 〉 0.05）. CONCLUSION： PNS can remarkably improve spatial learning and memory abilities of rats with AD. The therapeutic effect of PNS is not dose-dependent and is equivalent to the effect of huperzine A.

Panax notoginseng saponins influence on transplantation of neural stem cell-derived dopaminergic neurons in a rat model of Parkinson’s disease

BACKGROUND： Dopaminergic neurons differentiated from neural stem cells have been successfully used in the treatment of rat models of Parkinson＇s disease; however, the survival rate of transplanted cells has been low. Most cells die by apoptosis as a result of overloaded intracellular calcium and the formation of oxygen free radicals. OBJECTIVE： To observe whether survival of transplanted cells, transplantation efficacy, and dopaminergic differentiation from neural stem cells is altered by Panax notoginseng saponins （PNS） in a rat model of Parkinson＇s disease. DESIGN, TIME AND SETTING： Cellular and molecular biology experiments with randomized group design. The experiment was performed at the Animal Experimental Center, First Hospital of Sun Yat-sen University from April to October 2007. MATERIALS： Thirty-two adult, healthy, male Sprague Dawley rats, and four healthy Sprague Dawley rat embryos at gestational days 14-15 were selected. The right ventral mesencephalon was injected with 6-hydroxydopamine to establish a model of Parkinson＇s disease. 6-hydroxydopamine and apomorphine were purchased from Sigma, USA. METHODS： Neural stem cells derived from the mesencephalon of embryonic rats were cultivated and passaged in serum-free culture medium. Lesioned animals were randomly divided into four groups （n = 8）： dopaminergic neuron, dopaminergic neuron ＋ PNS, PNS, and control. The dopaminergic neuron group was injected with 3 μL cell suspension containing dopaminergic neurons differentiated from neural stem cells. The dopaminergic neurons ＋ PNS group received 3 μ L dopaminergic cell suspension combined with PNS （250 mg/L）. The PNS group received 3 μL PNS （250 mg/L）, and the control group received 3 μL DMEM/F12 culture medium. MAIN OUTCOME MEASURES： The rats were transcardially perfused with 4% paraformaldehyde at 60 days post-grafting for immunohistochemistry. The rats were intraperitoneally injected with apomorphine （0.5 mg/kg） to induce rotational behavior. RESULTS： Cell counts of tyrosine hydroxylase-positive neurons in the dopaminergic neuron ＋ PNS group were （732±82.6） cells/400-fold field. This was significantly greater than the dopaminergic neuron group [（326 ± 34.8） cells/400-fold field, P 〈 0.01]. Compared to the control group, the rotational asymmetry of rats that received dopaminergic neuron transplants was significantly decreased, beginning at 20 days after operation （P 〈 0.01）. Rotational asymmetry was further reduced between 10-60 days post-surgery in the dopaminergic neuron ＋ PNS group, compared to the dopaminergic neuron group （P 〈 0.01）. CONCLUSION： Panax notoginseng saponins can increase survival and effectiveness of dopaminergic neurons differentiated from neural stem cells for transplantation in a rat model of Parkinson＇s disease.

Effects of total saponins of Panax notoginseng on immature neuroblasts in the adult olfactory bulb following global cerebral ischemia/reperfusion

The main active components extracted from Panax notoginseng are total saponins. They have been shown to inhibit platelet aggregation, increase cerebral blood flow, improve neurological behavior, decrease infarct volume and promote proliferation and differentiation of neural stem cells in the hippocampus and lateral ventricles. However, there is a lack of studies on whether total saponins of Panax notoginsertg have potential benefits on immature neuroblasts in the olfactory bulb following ischemia and reperfusion. This study established a rat model of global cerebral ischemia and reperfusion using four-vessel occlusion. Rats were administered total sa- ponins of Panax notoginseng at 75 mg/kg intraperitoneally 30 minutes after ischemia then once a day, for either 7 or 14 days. Total saponins of Panax notoginseng enhanced the number of dou- blecortin （DCX）＋ neural progenitor ceils and increased co-localization of DCX with neuronal nuclei and phosphorylated cAMP response element-binding/DCX＋ neural progenitor cells in the olfactory bulb at 7 and 14 days post ischemia. These findings indicate that following global brain ischemia/reperfusion, total saponins of Panax notoginseng promote differentiation of DCX＋ cells expressing immature neuroblasts in the olfactory bulb and the underlying mechanism is related to the activation of the signaling pathway of cyclic adenosine monophosphate response element binding protein.

Yizhijiannao Granule and a combination of its effective monomers,icariin and Panax notoginseng saponins,inhibit early PC12 cell apoptosis induced by beta-amyloid(25-35)

One of our previous studies showed that Yizhijiannao Granule,a compound Chinese medicine, effectively improved the clinical symptoms of Alzheimer’s disease.In the present study,we established a model of Alzheimer’s disease using beta-amyloid（25-35）in PC12 cells,and treated the cells with Yizhijiannao Granule and its four monomers,i.e.,icariin,catechin,Panax notoginseng saponins,and eleutheroside E.Flow cytometry showed that Yizhijiannao Granule-containing serum, icariin,Panax notoginseng saponins,and icariin＋Panax notoginseng saponins were protective against beta-amyloid（25-35）-induced injury in PC12 cells.Icariin in combination with Panax notoginseng saponins significantly inhibited early apoptosis of PC12 cells with beta-amyloid （25-35）-induced injury compared to icariin or Panax notoginseng saponins alone.The effects of icariin＋Panax notoginseng saponins were similar to the effects of Yizhijiannao Granule.The findings indicate that two of the effective monomers of Yizhijiannao Granule,icariin and Panax notoginseng saponins,can synergistically inhibit early apoptosis of PC12 cells induced by beta-amyloid（25-35）.

Effects of Panax notoginseng saponins on hydrogen peroxide-induced apoptosis in cultured rabbit bone marrow stromal cells

Objective To investigate the effects of Panax notoginseng saponins(PNS)on hydrogen peroxide(H2O2)-induced apoptosis in cultured rabbit bone marrow stromal cells(BMSCs).Methods BMSCs from 3-month-old New Zealand rabbits were isolated and cultured by the density gradient centrifugation combined with adherent method.The cultured BMSCs were divided into three groups:normal control,H2O2 treatment(100μmol/L),and PNS pretreatment(0.1g/L).Intracellular reactive oxygen species(ROS)levels as the index of oxidative stress were measured by using 2’7’-dichlorodihydrofluorescein diacetate.Flow cytometry was used to observe the apoptosis of BMSCs by staining with annexinV-FITC/PI.The protein expression of Bax in BMSCs was analyzed by Western blotting.Activity of caspase-3 enzyme was measured by spectrofluorometry.Results Pretreatment with PNS significantly decreased intracellular ROS level induced by H2O2(P<0.01).PNS markedly attenuated H2O2-induced apoptosis rate from 38.68% to 19.24%(P<0.01).PNS reversed H2O2-induced augmentation of Bax expression.Furthermore,PNS markedly reduced the altered in activity of caspase-3 enzyme induced by H2O2(P<0.01).Conclusion PNS has a protective effect on hydrogen peroxide-induced apoptosis in cultured rabbit BMSCs by scavenging ROS and decreasing Bax expression and caspase-3 activity.

Protective effects of panax notoginseng saponin on dextran sulfate sodium-induced colitis in rats through phosphoinositide-3-kinase protein kinase B signaling pathway inhibition

BACKGROUND Intestinal inflammation is a common digestive tract disease, which is usually treated with hormone medicines. Hormone medicines are effective to some extent, but long-term use of them may bring about many complications.AIM To explore the protective effects of panax notoginseng saponin(PNS) against dextran sulfate sodium(DSS)-induced intestinal inflammatory injury through phosphoinositide-3-kinase protein kinase B(PI3K/AKT) signaling pathway inhibition in rats.METHODS Colitis rat models were generated via DSS induction, and rats were divided into control(no modeling), DSS, DSS + PNS 50 mg/k, and DSS + PNS 100 mg/kg groups. Then, the intestinal injury, oxidative stress parameters, inflammatory indices, tight junction proteins, apoptosis, macrophage polarization, and TLR4/AKT signaling pathway in colon tissues from rats in each of the groups were detected. The PI3 K/AKT signaling pathway in the colon tissue of rats was blocked using the PI3K/AKT signaling pathway inhibitor, LY294002.RESULTS Compared with rats in the control group, rats in the DSS group showed significantly shortened colon lengths, and significantly increased disease activity indices, oxidative stress reactions and inflammatory indices, as well as significantly decreased expression of tight junction-associated proteins. In addition, the DSS group showed significantly increased apoptotic cell numbers,and showed significantly increased M1 macrophages in spleen and colon tissues.They also showed significantly decreased M2 macrophages in colon tissues, as well as activation of the PI3K/AKT signaling pathway(all P < 0.05). Compared with rats in the DSS group, rats in the DSS + PNS group showed significantly lengthened colon lengths, decreased disease activity indices, and significantly alleviated oxidative stress reactions and inflammatory responses. In addition, this group showed significantly increased expression of tight junction-associated proteins, significantly decreased apoptotic cell numbers, and significantly decreased M1 macrophages in spleen and colon tissues. This group further showed significantly increased M2 macrophages in colon tissues, and significantly suppressed activation of the PI3K/AKT signaling pathway, as well as a dose dependency(all P < 0.05). When the PI3K/AKT signaling pathway was inhibited, the apoptosis rate of colon tissue cells in the DSS + LY294002 group was significantly lower than that of the DSS group(P < 0.05).CONCLUSION PNS can protect rats against DSS-induced intestinal inflammatory injury by inhibiting the PI3K/AKT signaling pathway, and therefore may be potentially used in the future as a drug for colitis.

Panax notoginseng saponins improve recovery after spinal cord transection by upregulating neurotrophic factors

Saponins extracted from Panax notoginseng are neuroprotective, but the mechanisms underlying this effect remain unclear. In the present study, we established a rat model of thoracic（T10） spinal cord transection, and injected Panax notoginseng saponins（100 mg/kg） or saline 30 minutes after injury. Locomotor functions were assessed using the Basso, Beattie, and Bresnahan（BBB） scale from 1 to 30 days after injury, and immunohistochemistry was carried out in the ventral horn of the spinal cord at 1 and 7 days to determine expression of nerve growth factor（NGF） and brain-derived neurotrophic factor（BDNF）. Our results show that at 7–30 days post injury, the BBB score was higher in rats treated with Panax notoginseng saponins than in those that received saline. Furthermore, at 7 days, more NGF- and BDNF-immunoreactive neurons were observed in the ventral horn of the spinal cord of rats that had received Panax notoginseng saponins than in those that received saline. These results indicate that Panax notoginseng saponins caused an upregulation of NGF and BDNF in rats with spinal cord transection, and improved hindlimb motor function.

Anticancer effects of saponin and saponin–phospholipid complex of Panax notoginseng grown in Vietnam

Objective:To evaluate the antitumor activity both in vitro and in vivo of saponin–phospholipid complex of Panax notoginseng.Methods:The in vitro cytotoxic effect of saponins extract and saponin–phospholipid complex against human lung cancer NCI-H460 and breast cancer cell lines BT474 was examined using MTS assay.For in vivo evaluation of antitumor potential,saponin and saponin–phospholipid complex were administered orally in rats induced mammary carcinogenesis by 7,12-dimethylbenz(a)anthracene,for 30 days.Results:Our data showed that saponin–phospholipid complex had stronger anticancer effect compared to saponin extract.The IC50 values of saponin–phospholipid complex and saponin extract for NCI-H460 cell lines were 28.47 mg/m L and 47.97 mg/mL,respectively and these values for BT474 cells were 53.18 mg/mL and 86.24 mg/mL,respectively.In vivo experiments,administration of saponin,saponin–phospholipid complex and paclitaxel(positive control) effectively suppressed 7,12-dimethylbenz(a) anthracene-induced breast cancer evidenced by a decrease in tumor volume,the reduction of lipid peroxidation level and increase in the body weight,and elevated the enzymatic antioxidant activities of superoxide dismutase,catalase,glutathione peroxidase in rat breast tissue.Conclusions:Our study suggests that saponin extract from Panax notoginseng and saponin–phospholipid complex have potential to prevent cancer,especially breast cancer.

Effects of Panax notoginseng saponins on apoptosis induced by hydrogen peroxide in cultured rabbit bone marrow stromal cells via altering the oxidative stress level and down-regulating caspase-3

Objective： To investigate the effects of Panax notoginseng saponins （PNS） on hydrogen peroxide （H2O2）-induced apoptosis in cultured rabbit bone marrow stromal cells （BMSCs）. Methods： The effects of different concentrations of PNS on proliferation and early osteoblast differentiation of BMSCs were determined by the MTT assay and an alkaline phosphatase （ALP） assay. An optimal effective concentration of PNS was determined and used in subsequent experiments. The cultured BMSCs were divided into three groups： untreated control, H2O2 treated, and PNS pretreatment of H2O2 treated. The oxidative stress level was assessed by superoxide dismutase （SOD） and malondialdehyde （MDA） assays. Flow cytometry was used to determine BMSC apoptosis by staining with annexinV-FITC/propidium iodide （PI）. The activity of caspase-3 enzyme was measured by spectrofluorometry. Results： PNS （0.1g/L） significantly increased both BMSC proliferation rate and ALP activity, while it decreased the indicators of oxidative stress, caspase-3 activity, and the apoptosis rate of BMSCs induced by H2O2.. Conclusion： PNS, acting as a biological antioxidant, had a protective effect on H2O2-induced apoptosis in cultured rabbit BMSCs by decreasing oxidative stress and down-regulating caspase-3.

Neuroprotective effect of panax notoginseng saponins and its main components

Stroke is the third leading cause of death and the first cause of adult disability in industrial countries [1]. It is charicaterized by hemiplegia, hemianopsia, aphasia, mouth askew and sever sequelae. It is considered that an ischemic disease without any specific treatment method and few effective drugs such as tPA (human tissue-type plasminogen activator) and Edarovone with specific therapeutic window will cause a lot of disadvantages if being used inaccurate. Root of Panax notoginseng (PN) which is one of traditional Chinese medicines (TCMs), was first found in “Shennong’s Classic of Materia Medica” around 200 AD. Panax notogineng saponins(PNS) is a multi-components mixture containing ginseng and saponins as the most important bioactive components which are commonly used in clinical treatment. Also, ginseng and saponins form the main components of many herbal medicines in the market, e.g., Xueshuantong injection [2], Xuesaitong injection [3], Xuesaitong soft capsule [4] and so on. The main monomers of Panax notoginseng saponins (PNS) are Ginsenoside-Rb1, Gensenoside-Rg1, Gensenoside-Re, Gensenoside-Rd and Panax notoginseng saponins-R1 [5]. In this review, we found some important points as well as shortcomings that require special consideration. We therefore highlighted the advances in neuro-protection of PNS and its main monomers in the area of experimental research.

Comparison of pharmacokinetics of different oral Panax notoginseng saponins using ultra-high performance liquid mass spectrometry

Objective:To discuss and compare the plasma pharmacokinetics after three oral Panax notoginseng saponin(PNS)administrations in beagle dogs.PNS is the main active ingredient of the traditional Chinese medicine(TCM)Panax notoginseng.Although its outstanding therapeutic efficacy has been demonstrated by various researchers,its broader application is restricted by the low bioavailability of PNS.Methods:An ultra-high performance liquid chromatographyetandem mass spectrometry(UPLC-MS/MS)method for the simultaneous quantification of notoginsenoside R1,ginsenoside Rg1,ginsenoside Rb1,ginsenoside Rd,and ginsenoside Re in beagle dog plasma was developed and validated.The plasma samples were subjected to liquideliquid extraction with acetone and methanol,and separated on an ACQUITY C18 column(100×2.1 mm ID,1.7 mm)using acetonitrile and water as the mobile phase with a run time of 4.5 min.Results:The analytes were detected without interference in Selected Reaction Monitoring mode with positive electrospray ionization.The validated method was successfully used in comparative pharmacokinetic studies of the five saponins in beagle dogs after oral administration of three PNS preparations.Blood samples were collected up to 192 h after administration and pharmacokinetic parameters were calculated using DAS 3.20 and SPSS 17.0.The AUC_(0-t)values of Re and R1 were significantly higher in soft capsules than in hard capsules.However,the AUC_(0-t)values between hard and soft capsules were not significantly different for the other three componentsdRb1,Rd and Rg1.Conclusion:Our intuitive analysis suggests that the bioavailability of PNS in soft capsules is greater than in hard capsules.

The neuroprotective role of Panax notoginseng saponins in APP/PS1 transgenic mice through the modulation of cerebrovascular

Background:Panax notoginseng saponins(PNS)is extracted from Sanqi(Panax notoginseng),which is a valuable herb and has been widely used in traditional Chinese medicine for the treatment of cerebrovascular diseases and pain.PNS has been proved to promote blood circulation and angiogenesis by inhibiting platelet aggregation.In our previous study,PNS accompanied with geniposide can prevent Alzheimer’s disease(AD).However,the efficacy of PNS and its potential mechanism in AD remain unclear.Methods:Amyloid precursor protein/presenilin-1(APP/PS1)transgenic(Tg)mice were used as AD-like animal models.Wild-type mice and APP/PS1 transgenic were administrated with saline solution while mice in PNS treatment group were administrated with PNS at a dosage of 17 mg/kg/day for three months.Morris water maze(MWM)was applied to evaluate the spatial learning and memory and step-down test was used to evaluate the cognitive function.1%Thioflavin-S staining was used to calculate the average number amyloid plaques in cortex and hippocampus.CD31 staining was detected to observe the density of cerebrovascular in hippocampus areas and CD105 staining was further detected to evaluate angiogenesis.Laser Doppler PeriFlux 5000 was further measured the change of cerebrovascular blood flow.ChemDraw was used to draw the molecular structures of five main ingredients of PNS.AlzPlatform were used to estimate the potential targets of PNS.Results:By a bench of behavioral tests,PNS showed a better tendency in proving cognitive functions.In addition,the amyloid plaques in both cortex and hippocampus were significantly reduced after PNS intervention(P<0.05 and P<0.001 respectively).Furthermore,the density of cerebrovascular in the hippocampus areas was increased under PNS administration(P<0.001),which accompanied with angiogenesis in dentate gyrus areas and cerebrovascular blood flow promotion(P<0.05).By AlzPlatform docking serve,we screened five major ingredients of PNS-R1,Rd,Rb1,Re and Rg1.These screening data suggested that vascular related proteins could be the one of potential targets of PNS,such as platelet activating factor receptor and vasopressin V1a receptor.Conclusion:By modulating cerebrovascular function,PNS can reduce the deposition of amyloid plaques and exhibit the role of neuroprotection in a preventive strategy.

Development and evaluation of Panax notoginseng saponins contained in an in situ pHtriggered gelling system for sustained ocular posterior segment drug delivery

Objective:This study aimed to lay the foundation for the research on Panax notoginseng saponins(PNS)in pH-sensitive in situ gel and the development and improvement of related preparations.Methods:We used Carbopol■940,a commonly used pH-sensitive polymer,and the thickener hydroxypropyl methylcellulose(HPMC E4M)as an ophthalmic gel matrix to prepare an ophthalmic in situ gel of PNS.In addition,formula optimization was performed by assessing gelling capability with the results of in vitro release studies.In vitro(corneal permeation,rheological,and stability)and in vivo(ocular irritation and preliminary pharmacokinetics in the vitreous)studies were also performed.Results:The results demonstrated that the in situ gelling systems containing PNS showed a sustained release of the drug,making it an ideal ocular delivery system for improving posterior ocular bioavailability.Conclusions:This study lays the foundation for the research of PNS contained in an in situ pH-triggered gel as well as the development and improvement of related preparations.It concurrently traditional Chinese medicine with a contemporary in situ gelling approach to provide new directions for the treatment of posterior ocular diseases such as diabetic retinopathy.

Effects of Paeonol Combined with Panax Notoginseng Saponins on Nrf2/ARE Pathway in Rats with Diabetic Cardiomyopathy

[Objectives]To investigate whether paeonol(Pae)combined with panax notoginseng saponins(PNS)can protect the myocardium of rats with diabetic cardiomyopathy(DCM)through improving the antioxidant capacity of the rats by activating the Nrf2/ARE pathway.[Methods]The rats were fed with high-fat and high-sugar diet for 6 weeks,and combined with intraperitoneal injection of small-dose STZ to build a type II diabetes model;the model rats were randomly divided into a model group,a Pae group of 80 mg/kg,and a PNS group of 100 mg/kg,a Pae 80 mg/kg+PNS 100 mg/kg,and a metformin group 157.5 mg/kg;rats of normal group and model group were injected with an equal volume of sodium carboxymethyl cellulose(1%),10 rats in each group.After 8 weeks,3 rats in the model group were taken for histopathological examination.Changes in myocardial fibrosis and myocardial collagen formation indicated that the building of DCM model was successful.qRT-PCR and Western blot were used to detect the expression levels of Nrf2,HO-1,Col-I,and Col-III in myocardial tissue of each group of rats.[Results]Compared with the normal group,the mRNA and protein expression levels of Nrf2 and HO-1 in myocardial tissue of the DCM group rats were significantly reduced,and the mRNA and protein expression levels of Col-I and Col-III were significantly increased;compared with the DCM group,the mRNA and protein expression levels of Nrf2 and HO-1 in the myocardial tissue of each drug group increased to varying degrees,and the combined drug group increased more significantly than that of the single drug group;the mRNA and protein expression levels of Col-I and Col-III were reduced to varying degrees,and the combined drug group declined more significantly than that of the single drug group.[Conclusions]Paeonol combined with panax notoginseng saponins can up-regulate the expression of Nrf2 and HO-1 in myocardial tissue,inhibit the expression of type I and type III collagen.The mechanism may be related to improving the DCM myocardial fibrosis through activating the Nrf2/ARE pathway.

Recent Progress in Structural Modification and Activities on Panax notoginseng Saponins

This paper reviews recent progress in the structural modification and activities on Panax notoginseng saponins(PNS).PNS can not only improve the function of cardio-cerebral system,central nervous system and immune system,but also reveal anticancer,anti-aging and anti-oxidation activities.In order to solve the problem of low bioavailability and poor absorbability of PNS in vivo,usually,the researchers modified the structure of PNS with three methods:glycoside cleavage(including acid hydrolysis,sulfation,etc.),biotransformation method(including enzyme hydrolysis,microbial transformation)and combinatorial chemical method.It was found that the structural modification sites of PNS were single,mainly aimed at C-3,C-6 and C-20,which provided a new perspective for the structural modification of PNS.Therefore,structural modification on PNS with high yield and ready availability are significant in the discovery of new active ingredients and industrialization.Derivatives of PNS are applied to research of structure-activity relationship,which is beneficial to the development of new medicines.

Atherosclerosis lesion is accelerated by persistent systemic inflammation but attenuated by saponins from Panax Notoginseng in rabbits

Objective： To explore the roles of persistent systemic inflammation in atherosclerosis and the effects of saponins of Panax Notoginseng （PNS） on this process in rabbits. Methods： Thirty rabbits were divided randomly and equally into 6 groups, i.e., control, high-fat diet, inflammation, aspirin, PNS and simple-inflammation group. All the animals except that in control group and simple-inflammation group were fed with high-fat diet for 8 weeks. Based on that, rabbits in inflammation, aspirin and PNS groups were treated with zymosan injection （10 mg/kg, i.p.）. Normal saline was given to rabbits in control group. Besides zymosan injection, animals in aspirin and PNS group were administrated with aspirin （12 mg/kg, i.g.） and PNS （120 mg/kg, i.g.） respectively. The animals in simple-inflammation group were treated with zymosan injection （10mg/kg, i.p.） and fed with normal diet. The atherosclerosis lesion in aortas was observed by Sudan IV staining. Serum total cholesterol, triglyceride （TG）, TNF-α and activity of post-heparin lipoprotein lipase （LPL） were measured at the end of the 4th and 8th week after an overnight fast. Results： Compared with high-fat diet group, the area of atherosclerosis lesion, serum TG and TNF-α were markedly increased in rabbits of inflammation group, and the activity of LPL was decreased remarkably. Serum TNF-α level was negatively correlated with the activity of post-heparin LPL （r=0.708, P〈0.01）. The area of atherosclerosis, serum TG and TNF-α were decreased in aspirin and PNS group compared with that in inflammation group, and the activity of LPL was increased remarkably. Compared with control group, serum TG and TNF-α were markedly increased in simple-inflammation group, while LPL activity was decreased. Atherosclerotic lesion did not occur in simple-inflammation group. Conclusion： Persistent systemic inflammation could accelerate the formation of atherosclerosis lesion in aortas, which partly depend on the decreasing of the activity of post-heparin lipoprotein lipase. PNS could improve the changes caused by inflammation.