Panax notoginseng Saponins Attenuate Phenotype Switching of Vascular Smooth Muscle Cells Induced by Notch3 Silencing

Using mRNA deep sequencing to analyze differentially expressed genes during Panax notoginseng saponin treatment of ischemic stroke

Treatment with Panax notoginseng saponin (PNS) can prevent neurological damage in middle cerebral artery occlusion model rats to promote recovery after a stroke. However, the exact molecular mechanisms are unknown and require further study. In the present study, mRNA sequencing was employed to investigate differential gene expression between model and sham groups, and between model and PNS‑treated groups. Enrichment of gene data was performed using Gene Ontology analysis and the Kyoto Encyclopedia of Genes and Genomes database. Hub genes were identified and networks were constructed using Cytoscape that were further verified by reverse transcription‑quantitative PCR. A total of 1,104 genes of interest were found, which included 690 upregulated and 414 downregulated genes that were identified when the model was compared with the sham group. Additionally, 817 genes of interest, which included 390 upregulated and 427 downregulated genes, were identified when the PNS‑treated group was compared with the model group. There were 303 overlapping genes of interest between the analysis of model to sham groups, and the analysis of model to PNS‑treated groups. The top 10 genes from the 303 aberrantly expressed genes of interest included ubiquitin conjugating enzyme E2 variant 2, small ubiquitin‑related modifier 1, small RNA binding exonuclease protection factor La, Finkel‑Biskis‑Reilly murine sarcoma virus (FBR‑MuSV) ubiquitously expressed, centrosomal protein 290 kDa, DNA‑directed RNA polymerase II subunit K, cullin‑4B, matrin‑3 and vascular endothelial growth factor receptor 2. In conclusion, these genes may be important in the underlying mechanism of PNS treatment in ischemic stroke. Additionally, the present data provided novel insight into the pathogenesis of ischemic stroke.

Analytical methods and biological activities of Panax notoginseng saponins: Recent trends

ETHNOPHARMACOLOGICAL RELEVANCE

Panax notoginseng (Burk.) F. H. Chen, also called Sanqi, is a widely used traditional Chinese medicine, which has long history used as herbal medicines. It is currently an important medicinal material in China, holding the first place in the sale volume of the whole patent medicines market in China, and the market size of the single species has exceeded 10 billion yuan. In addition, P. notoginseng is an important constituent part of many famous Chinese patent medicines, such as Compound Danshen Dripping Pills and Yunnan Baiyao. P. notoginseng saponins (PNSs), which are the major active components of P. notoginseng, are a kind of chemical mixture containing different dammarane-type saponins. Many studies show that PNSs have been extensively used in medical research or applications, such as atherosclerosis, diabetes, acute lung injury, cancer, and cardiovascular diseases. In addition, various PNS preparations, such as injections and capsules, have been made commercially available and are widely applied in clinical practice.

AIM OF THE REVIEW

Since the safety and efficacy of compounds are related to their qualitative and quantitative analyses, this review briefly summarizes the analytic approaches for PNSs and their biological effects developed in the last decade.

METHODOLOGY

This review conducted a systematic search in electronic databases, such as Pubmed, Google Scholar, SciFinder, ISI Web of Science, and CNKI, since 2009. The information provided in this review is based on peer-reviewed papers and patents in either English or Chinese.

RESULTS

At present, the chromatographic technique remains the most extensively used approach for the identification or quantitation of PNSs, coupled with different detectors, among which the difference mainly lies in their sensitivity and specificity for analyzing various compounds. It is well-known that PNSs have traditionally strong activity on cardiovascular diseases, such as atherosclerosis, intracerebral hemorrhage, or brain injury. The recent studies showed that PNSs also responded to osteoporosis, cancers, diabetes, and drug toxicity. However, some other studies also showed that some PNSs injections and special PNS components might lead to some biological toxicity under certain dosages.

CONCLUSION

This review may be used as a basis for further research in the field of quantitative and qualitative analyses, and is expected to provide updated and valuable insights into the potential medicinal applications of PNSs.

Panax notoginseng Saponins Attenuate Oxygen-Glucose Deprivation/Reoxygenation-Induced Injury in Human SH-SY5Y Cells by Regulating the Expression of Inflammatory Factors through miR-155

Panax notoginseng saponins (PNS) have been widely used in China to treat stroke. Accumulating evidence has found that microRNA (miR)-155 plays critical roles in the pathology of ischemic stroke. Here we investigated whether PNS plays a protective effect against oxygen-glucose deprivation/reoxygenation (OGD/R)-induced focal inflammation and injury in SH-SY5Y cells by regulating miR-155 expression. Treatment with PNS at a concentration less than 160 µg/mL had no effect on the proliferation of SH-SY5Y cell. In OGD/R-induced SH-SY5Y cells, 160 µg/mL PNS treatment promoted cell proliferation and cell cycle progression, as well as decreased inhibited apoptosis and miR-155 expression. However, overexpression of miR-155 attenuated the promotion effects of PNS on cell proliferation and cell cycle, apoptosis inhibition in OGD/R-induced SH-SY5Y cells. Moreover, 160 µg/mL PNS treatment decreased the levels of interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α) in OGD/R-induced SH-SY5Y cells, whereas overexpression of miR-155 reversed PNS-induced decreases in the levels of IL-1β, IL-6, and TNF-α in OGD/R-treated SH-SY5Y cells. In conclusion, PNS attenuated OGD/R-induced injury in human undifferentiated SH-SY5Y cells by regulating the expression of inflammatory factors through miR-155.

Panax notoginseng Saponins Regulate Macrophage Polarization under Hyperglycemic Condition via NF-κB Signaling Pathway

Panax notoginseng saponins (PNS), the principal constituents derived from Panax notoginseng, have been extensively used for treating cardiocerebral vascular diseases in China and other Asian countries. The main effects of PNS were anti-inflammatory properties, inhibition of platelet aggregation, improvement of blood flow and insulin resistance, and so on. This study was carried out to explore the effects of PNS on macrophage polarization under hyperglycemic conditions. Human acute monocyte leukemia cell line THP-1 cells were induced into macrophages with Phorbol ester (PMA). Macrophages were then divided into five groups as follows: control (5.5mMol/l glucose), hyperglycemia group (15mMol/l glucose), hyperglycemia plus low-dose PNS (20ug/ml), hyperglycemia plus moderate-dose PNS (40ug/ml), and hyperglycemia plus high-dose PNS (60ug/ml). After 48-hour cell culture, the percentages of M1- and M2-polarized macrophages were measured by flow cytometry analysis. Reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) was used to evaluate the Ym1 and arginase 1 expression in macrophages. Protein expression of arginase 1, NF-κB p50, p65, and inhibitor of κB (IκB) alpha phosphorylation in macrophages was identified with Western blotting. PNS, especially the high-dose PNS, remarkably increased M2 phenotype ratio in macrophages cultured with hyperglycemia, and the mRNA expression of Ym1 and arginase 1 in macrophages was also upregulated. Meanwhile, PNS remarkably increased the protein expression of arginase 1 and decreased IκB-alpha phosphorylation and subunits of NF-κB p50 and p65 from macrophages in culture medium with hyperglycemia. Taken together, our work demonstrated that PNS promote macrophages to transform M2 phenotype under hyperglycemic conditions through downregulating NF-κB signaling pathway.

Effects of panax notoginseng saponins on the osteogenic differentiation of rabbit bone mesenchymal stem cells through TGF-β1 signaling pathway

Background

Panax Notoginseng is a well-known Chinese medicinal herb which has been used in China for treatment of bone fracture for hundreds of years. However, the specific biological mechanisms of osteogenic effect of PNS are not well understood.

Methods

In this study, newborn rabbit BMSCs were isolated, and then identified by the positive expression rates of cell surface markers, including CD29, CD45 and HLA-DR, which were detected by flow cytometry(FCM). After the lentivirus-induced cell model of TGF-β1 gene silencing was established, the interference efficiency was tested by q-PCR and Western blot, and the growth curve of silencing cells was drawn by MTT so as to grasp the growth rhythm of silencing cells. In the alizarin red-staining experiment, the effect of 100 mg/L PNS on the activity of intracellular ALP of TGF-β1 gene silencing BMSCs was detected, so as to observe the effect of 100 mg/L PNS on the formation of calcium nodes of gene silencing BMSCs.

Results

By separating rabbit BMSCs, the lentivirus-induced cell model of TGF-β1 gene silencing was established. Both TGF-β1 mRNA and protein expression were restrained significantly, and the target gene kept silence stably via the verification of q-PCR and Western blot; there was no significant differences of the growth curve between RNAi cells and normal cells; the activity of intracellular APL in 100 mg RNAi group was obviously lower than that in 100 mg group (p < 0.05), but higher than that in the normal group; in the alizarin red-staining experiment, it focused on the effects of PNS on the formation of calcium nodes of gene silencing BMSCs, which showed that calcium nodes could be formed in 100 mg RNAi group but its quantity was lower than that of 100 mg group (p < 0.05).

Conclusions

It was shown that silencing TGF-β1 gene could interrupt the osteogenic effects of PNS. PNS may have a promoting effect on osteogenic differentiation of rabbits’ BMSCs in vitro by up-regulating the gene expression of TGF-β1.

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

ETHNOPHARMACOLOGICAL RELEVANCE

Panax notoginseng saponins (PNS) extracted from a traditional Chinese herbal medicine, Panax notoginseng (Burkill) F.H. Chen (Araliaceae), which has been extensively used in treating coronary heart disease, ischemic cerebrovascular disease and hemorrhagic disorders in China over hundreds of years.

AIMS OF THE STUDY

This study explored whether panax notoginseng saponins (PNS) provided neuroprotective effects by inhibiting the expressions of NgR1, RhoA, and ROCK2 following middle cerebral artery occlusion in rats and oxygen-glucose deprivation/reoxygenation (OGD/R) injury in SH-SY5Y cells.

MATERIALS AND METHODS

2,3,5-Triphenyltetrazolium chloride staining was used to determine successful middle cerebral artery occlusion establishment in sham-operated and operated Sprague-Dawley rats 1 day after injury. The rats were randomly separated into sham, model, NEP1-40, PNS, and NEP1-40 plus PNS (N+P) groups. After 7 days of treatment, body mass and neurological deficit scores were analyzed. Tissues were harvested and analyzed by hematoxylin-eosin staining and immunohistochemical analysis, western blotting, and quantitative real-time PCR (qRT-PCR). The optimal drug concentration of NEP1-40 and PNS on SH-SY5Y cells exposed to OGD/R injury was determined by CCK8 analysis. qRT-PCR was used to measure mRNA expression profiles of NgR1, RhoA, and ROCK2 in SH-SY5Y cells subjected to OGD/R.

RESULTS

The results showed that MCAO surgery successfully produced an infarct, and the PNS, NEP1-40, and N+P groups exhibited increased body mass and ameliorated neurological deficits compared with the model group. NEP1-40 treatment markedly reduced NgR1 and RhoA overexpression when compared to the model group, although there was no significant difference in ROCK2 expression. PNS and N+P treatment significantly decreased NgR1, RhoA, and ROCK2 overexpression compared with the model group. However, N+P treatment did not result in a synergistic effect, as assessed by immunohistochemistry, western blotting, and qRT-PCR. Following optimal administration of PNS (160μg/ml) and NEP1-40 (10ng/ml) on SH-SY5Y cells exposed to OGD/R injury, cell viability in the NEP1-40, PNS, and N+P groups significantly increased compared with the model group, as assessed by CCK8 analysis. Additionally, NgR1, RhoA, and ROCK2 mRNA expression profiles were significantly less in the NEP1-40, PNS, and N+P groups compared with the model group.

CONCLUSION

PNS provided neuroprotective effects in a rat model of cerebral ischemia and SH-SY5Y cells exposed to oxygen/glucose deprivation injury by inhibiting the overexpression of NgR1, RhoA, and ROCK2.

Protective Effects of Panax notoginseng Saponins against High Glucose-Induced Oxidative Injury in Rat Retinal Capillary Endothelial Cells

Diabetic retinopathy, a leading cause of visual loss and blindness, is characterized by microvascular dysfunction. Hyperglycemia is considered the major pathogenic factor for diabetic retinopathy and is associated with increased oxidative stress in the retina. In this study, we investigated the potential protective effects of Panax notoginseng Saponins (PNS) in retinal capillary endothelial cells (RCECs) exposed to high glucose conditions. We found a pronounced increase in cell viability in rat RCECs incubated with both PNS and high glucose (30 mM) for 48 h or 72 h. The increased viability was accompanied by reduced intracellular hydrogen peroxide (H₂O₂) and superoxide (O₂⁻), decreased mitochondrial reactive oxygen species (ROS), and lowered malondialdehyde (MDA) levels. PNS also increased the activities of total superoxide dismutase (SOD), MnSOD, catalase (CAT), and glutathione peroxidase (GSH-PX). The glutathione (GSH) content also increased after PNS treatment. Furthermore, PNS reduced NADPH oxidase 4 (Nox4) expression. These results indicate that PNS exerts a protective effect against high glucose-induced injury in RCECs, which may be partially attributed to its antioxidative function.