Ginsenoside Rb1 Prevents MPP(+)-Induced Apoptosis in PC12 Cells by Stimulating Estrogen Receptors with Consequent Activation of ERK1/2, Akt and Inhibition of SAPK/JNK, p38 MAPK

Ginsenosides Rg1, Rb1 and rare ginsenosides: Promising candidate agents for Parkinson's disease and Alzheimer's disease and network pharmacology analysis

Ginseng has been commonly used as a traditional Chinese medicine in Asian countries for thousands of years. Ginsenosides are the main pharmacologically active ingredients isolated from ginseng and have neuroprotective effects in the treatment of neurodegenerative disorders, such as Parkinson's disease (PD) and Alzheimer's disease (AD). To summarise and investigate the protective roles of ginsenosides and their underlying mechanisms in PD and AD, we used ''Ginsenoside", ''Parkinson's disease", ''Alzheimer's disease", ''anti-inflammatory", ''antioxidant", and ''apoptosis" as keywords to search and extract relevant literature information from scientific databases such as Elsevier, PubMed, and Google Scholar databases. In particular, we used network pharmacology to identify the potential targets of ginsenosides Rg1 and Rb1 in PD and AD. By analysing the existing research advances and network pharmacology results, we found that the neuroprotective effects of ginsenosides, primarily mediated through anti-inflammation, anti-apoptosis and anti-oxidative stress, etc, may be associated with the PI3K/Akt, BDNF/TrkB, MAPKs, NF-κB, Nrf2 and Wnt/β-catenin signalling pathways. This review systematically summarises the different roles and mechanisms of ginsenosides Rg1, Rb1, and rare ginsenosides in PD and AD and provides new strategies for the treatment of neurodegenerative disorders. Network pharmacology provides a new research paradigm for the treatment of PD and AD using Rg1 and Rb1.

Panax notoginseng: Pharmacological Aspects and Toxicological Issues

Current evidence suggests a beneficial role of herbal products in free radical-induced diseases. Panax notoginseng (Burk.) F. H. Chen has long occupied a leading position in traditional Chinese medicine because of the ergogenic, nootropic, and antistress activities, although these properties are also acknowledged in the Western world. The goal of this paper is to review the pharmacological and toxicological properties of P. notoginseng and discuss its potential therapeutic effect. A literature search was carried out on Pubmed, Scopus, and the Cochrane Central Register of Controlled Trials databases. The following search terms were used: "notoginseng", "gut microbiota", "immune system", "inflammation", "cardiovascular system", "central nervous system", "metabolism", "cancer", and "toxicology". Only peer-reviewed articles written in English, with the full text available, have been included. Preclinical evidence has unraveled the P. notoginseng pharmacological effects in immune-inflammatory, cardiovascular, central nervous system, metabolic, and neoplastic diseases by acting on several molecular targets. However, few clinical studies have confirmed the therapeutic properties of P. notoginseng, mainly as an adjuvant in the conventional treatment of cardiovascular disorders. Further clinical studies, which both confirm the efficacy of P. notoginseng in free radical-related diseases and delve into its toxicological aspects, are mandatory to broaden its therapeutic potential.

Regulation of mitophagy and mitochondrial function: Natural compounds as potential therapeutic strategies for Parkinson's disease

Mitochondrial damage is associated with the development of Parkinson's disease (PD), indicating that mitochondrial-targeted treatments could hold promise as disease-modifying approaches for PD. Notably, natural compounds have demonstrated the ability to modulate mitochondrial-related processes. In this review article, we discussed the possible neuroprotective mechanisms of natural compounds against PD in modulating mitophagy and mitochondrial function. A comprehensive literature search on natural compounds related to the treatment of PD by regulating mitophagy and mitochondrial function was conducted from PubMed, Web of Science and Chinese National Knowledge Infrastructure databases from their inception until April 2023. We summarize recent advancements in mitophagy's molecular mechanisms, including upstream and downstream processes, and its relationship with PD-related genes or proteins. Importantly, we highlight how natural compounds can therapeutically regulate various mitochondrial processes through multiple targets and pathways to alleviate oxidative stress, neuroinflammation, Lewy's body aggregation and apoptosis, which are key contributors to PD pathogenesis. Unlike the single-target strategy of modern medicine, natural compounds provide neuroprotection against PD by modulating various mitochondrial-related processes, including ameliorating mitophagy by targeting the PINK1/parkin pathway, the NIX/BNIP3 pathway, and autophagosome formation (i.e., LC3 and p62). Given the prevalence of mitochondrial damage in various neurodegenerative diseases, exploring the exact mechanism of natural compounds on mitophagy and mitochondrial dysfunction could shed light on the development of highly effective disease-modifying or adjuvant therapies targeting PD and other neurodegenerative disorders.

Progress of Ginsenoside Rb1 in neurological disorders

Ginseng is frequently used in traditional Chinese medicine to treat neurological disorders. The primary active component of ginseng is ginsenoside, which has been classified into more than 110 types based on their chemical structures. Ginsenoside Rb1 (GsRb1)-a protopanaxadiol saponin and a typical ginseng component-exhibits anti-inflammatory, anti-oxidant, anti-apoptotic, and anti-autophagy properties in the nervous system. Neurological disorders remain a leading cause of death and disability globally. GsRb1 effectively treats neurological disorders. To contribute novel insights to the understanding and treatment of neurological disorders, we present a comprehensive review of the pharmacokinetics, actions, mechanisms, and research development of GsRb1 in neurological disorders.

Ginsenoside Rb1 alleviates chronic intermittent hypoxia-induced diabetic cardiomyopathy in db/db mice by regulating the adenosine monophosphate-activated protein kinase/Nrf2/heme oxygenase-1 signaling pathway

OBJECTIVE

To examine the protective effect of ginsenoside Rb1 (Rb1), the main component of Renshen (), on cardiomyopathy in db/db mice exposed to chronic intermittent hypoxia (CIH) and explore the potential underlying mechanism of Rb1 in treating diabetic cardiomyopathy (DCM).

METHODS

The db/db mice were randomly separated into five groups: normal control group, model group, Rb1 20 mg/kg group, Rb1 40 mg/kg group, and glucagon-like peptide-1 (GLP-1) group. Mice were exposed to air-condition or CIH for 8 weeks, and Rb1 and GLP-1 were administrated before CIH exposure every day. Oral glucose tolerance test (OGTT), intraperitoneal insulin tolerance test (IPITT), total cholesterol (TC), triglyceride (TG), and high-density lipoprotein cholesterol (HDL-C) were detected to evaluate glycolipid metabolism. The level of insulin was detected by a mouse enzyme-linked immunosorbent assay (ELISA). Cardiac function was detected by echocardiography, and myocardial pathology was observed by hematoxylin-eosin and Masson staining. The expression of collagen Ⅰ and collagen Ⅲ was detected by immunohistochemistry. Adenosine monophosphate-activated protein kinase (AMPK)/Nrf2/heme oxygenase-1 (HO-1) signaling pathway was detected by Western blot and immunofluorescence.

RESULTS

Rb1 treatment could improve glucose tolerance and the level of cardiac function indexes, and inhibit the level of oxidative stress indexes and the expression of collagen Ⅰ and collagen Ⅲ. Moreover, Rb1 treatment enhanced AMPK phosphorylation and increased Nrf2 and HO-1 expression.

CONCLUSION

Rb1 treatment alleviated CIH-induced diabetic cardiomyopathy and glycolipid metabolism disorders in db/db mice by inhibiting oxidative stress and regulating the AMPK/Nrf2/HO-1 signaling pathway.

Prevention of Deep Vein Thrombosis by Panax Notoginseng Saponins Combined with Low-Molecular-Weight Heparin in Surgical Patients

OBJECTIVE

To evaluate the efficacy of deep vein thrombosis (DVT) prevention among real-world surgical inpatients who received panax notoginseng saponins (PNS) combined with low-molecular-weight heparin (LMWH).

METHODS

A prospective cohort study was conducted among surgical patients between January 2016 and November 2018 in Xuanwu Hospital, Capital Medical University, Beijing, China. Participants received LMWH alone or PNS combined with LMWH for preventing DVT. The primary outcome was incidence of lower extremity DVT, which was screened once a week. Participants in the LMWH group were given LMWH (enoxaparin) via hypodermic injection, 4000-8000 AxalU once daily. Participants in the exposure group received PNS (Xuesaitong oral tablets, 100 mg, 3 times daily) combined with LMWH given the same as LMWH group.

RESULTS

Of the 325 patients screened for the study, 281 participants were included in the final analysis. The cohort was divided into PNS + LMWH group and LMWH group with 134 and 147 participants, respectively. There was a significant difference of DVT incidence between two groups (P=0.01), with 21 (15.7%) incident DVT in the PNS + LMWH group, and 41 (27.9%) incident DVT in the LMWH group. Compared with participants without DVT, the participants diagnosed with DVT were older and had higher D-dimer level. The multivariate logistic regression model showed a significant lower risk of incident DVT among participants in the PNS + LMWH group compared with the LMWH group (odds ratio 0.46, 95% confidence interval, 0.25-0.86). There were no significant differences in thromboelaslography values (including R, K, Angle, and MA) and differences in severe bleeding between two groups. No symptomatic pulmonary embolism occurred during the study.

CONCLUSION

Combined application of PNS and LMWH can effectively reduce the incidence of DVT among surgical inpatients compared with LMWH monotherapy, without increased risk of bleeding.

Ginsenoside-Rb1 prevents bone cartilage destruction through down-regulation of p-Akt, p-P38, and p-P65 signaling in rabbit

BACKGROUND

Osteoarthritis (OA) is the most common joint complaint resulting in pain, disability, and loss of quality of life. On the other hand, ginsenoside-Rb1 is a plant product derived from ginseng that possesses immune-regulation and anti-inflammatory activities. However, it has been reported that different rout of administration but hydrogel-based Ginsenoside-Rb1 in an OA rabbit model has not been investigated.

PURPOSE

The aim of this study was to investigate the potential effects of ginsenoside-Rb1 such as anti-arthritic activity in a rabbit knee OA model via NF- κB, PI3K/Akt, and P38/(MAPK) pathways.

STUDY DESIGN

In the current study, rabbit osteoarthritis was induced by hollow trephine on the femur trochlea and the hydrogel-based Ginsenoside-Rb1 sheets were inserted on the rabbit knee to assess the anti-arthritis activity of ginsenoside-Rb1 which is sustained release.

METHODS

After the hydrogel-based Rb1 sheet insert on the rabbit knee, macroscopic and micro CT was performed for investigation of chondroprotective effect. Matrix metalloproteinases (MMPs) and apoptotic expression were assessed through Immunohistochemistry and RT-PCR assay. In addition, the flow cytometry technique was used for the investigation of intracellular reactive oxygen species (ROS) production and histological changes were examined by HE, safranin O, and Masson trichrome staining method. Furthermore, the NF- κB, PI3K/Akt, and P38/(MAPK) pathways were investigated using Western blot analysis.

RESULTS

Macroscopic and micro CT investigation of hydrogel-Rb1 treatment showed a dose-dependent chondroprotective effect. Immunohistochemistry and RT-PCR revealed that expression of matrix metalloproteinases (MMPs) and apoptotic markers TNF-α, caspase-3, and bax are down-regulated in a dose-dependent fashion following implantation of hydrogel-Rb. Higher levels of intracellular reactive oxygen species (ROS) were observed in the OA group. In histopathological investigation of hydrogel-Rb1 exhibited larger amounts of chondro cells, glycosaminoglycan's, and collagen compared to the defect group. Furthermore, the NF- κB, PI3K/Akt, and P38/(MAPK) pathways were downregulated by hydrogel-Rb1 while the disease model showed upstream. In the meantime, MMP expression level was considerably down-regulated.

CONCLUSIONS

Our results indicate the protective effect of ginsenoside-Rb1 against OA pathogenesis through prevention of apoptosis with suppression of ROS production and activation of NF-κB signaling through downregulation of the MAPK and PI3K/Akt signaling pathways.

Therapeutic implications of glucose transporters (GLUT) in cerebral ischemia

Cerebral ischemia is a leading cause of death in the globe, with a large societal cost. Deprivation of blood flow, together with consequent glucose and oxygen shortage, activates a variety of pathways that result in permanent brain damage. As a result, ischemia raises energy demand, which is linked to significant alterations in brain energy metabolism. Even at the low glucose levels reported in plasma during ischemia, glucose transport activity may adjust to assure the supply of glucose to maintain normal cellular function. Glucose transporters in the brain are divided into two groups: sodium-independent glucose transporters (GLUTs) and sodium-dependent glucose cotransporters (SGLTs).This review assess the GLUT structure, expression, regulation, pathobiology of GLUT in cerebral ischemia and regulators of GLUT and it also provides the synopsis of the literature exploring the relationship between GLUT and the various downstream signalling pathways for e.g., AMP-activated protein kinase (AMPK), CREB (cAMP response element-binding protein), Hypoxia-inducible factor 1 (HIF)-1, Phosphatidylinositol 3-kinase (PI3-K), Mitogen-activated protein kinase (MAPK) and adenylate-uridylate-rich elements (AREs). Therefore, the aim of the present review was to elaborate the therapeutic implications of GLUT in the cerebral ischemia.

The Protective Effect of Ginsenoside Rg1 on Apoptosis in Human Ankle Joint Traumatic Arthritis Chondrocytes

The ankle biomechanics is easily changed due to the acute injury of the tissue around the ankle joint and the damage of the ankle joint structure, such as ankle instability and joint surface imbalance. When the mechanical load of the ankle changes, it can cause ankle regeneration and remodeling processes such as cartilage loss, bone remodeling, and degenerative changes. The aim of this study was to investigate the effect and mechanism of ginsenoside Rg1 against interleukin-1β (IL-1β)-induced apoptosis in human articular chondrocytes (HACs). The apoptosis model of HAC cells was established by IL-1β induction, and then the HAC cells were cultured with different concentrations of Rg1. The protective effect of Rg1 on HAC cell apoptosis was investigated by detecting the changes of apoptosis and activity of PI3K/Akt/mitochondrial signaling pathway. The results showed that a specific concentration of Rg1 could promote the proliferation of IL-1β-induced HAC cells and inhibit apoptosis. At the same time, Rg1 treatment with specific concentration can reduce the content of reactive oxygen species (ROS) and malondialdehyde (MDA) in HACs and improve the related expression of mitochondrial membrane potential (MMP). Furthermore, qRT-PCR and western blot results showed that Rg1 could improve the low expression of Bcl-2 and inhibit the high expression of Bax, caspase-3, caspase-8, caspase-9, FasL, AIF, and Cyto c in IL-1β-induced cells. In summary, Rg1 can inhibit IL-1β-induced apoptosis of HAC cells by decreasing the activity of PI3K/Akt/mitochondrial signaling pathway, and Rg1 has a protective effect on apoptosis of HAC cells.

The promising therapeutic potentials of ginsenosides mediated through p38 MAPK signaling inhibition

The p38 mitogen-activated protein kinases (p38 MAPK) is a 38kD polypeptide recognized as the target for many potential anti-inflammatory agents. Accumulating evidence indicates that p38 MAPK could perform many roles in human disease pathophysiology. Therefore, great therapeutic benefits can be attained from p38 MAPK inhibitors. Ginseng is an exceptionally valued medicinal plant of the family Araliaceae (Panax genus). Recently, several studies targeted the therapeutic effects of purified individual ginsenoside, the most significant active ingredient of ginseng, and studied its particular molecular mechanism(s) of action rather than whole-plant extracts. Interestingly, several ginsenosides: ginsenosides compound K, F1, Rb1, Rb3, Rc, Rd, Re, Rf, Rg1, Rg2, Rg3, Rg5, Rh1, Rh2, Ro, notoginsenoside R1, and protopanaxadiol have shown to possess great therapeutic potentials mediated by their ability to downregulate p38 MAPK signaling in different cell lines and experimental animal models. Our review compiles the research findings of various ginsenosides as potent anti-inflammatory agents, highlighting the crucial role of p38 MAPK suppression in their pharmacological actions. In addition, in silico studies were conducted to explore the probable binding of these ginsenosides to p38 MAPK. The results obtained proposed p38 MAPK involvement in the beneficial pharmacological activities of ginsenosides in different ailments.

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p38 MAPK plays many roles in human disease pathophysiology. Therefore, great therapeutic benefits can be attained from p38 MAPK inhibitors.

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Several ginsenosides showed to possess great therapeutic potentials mediated by its ability to downregulate p38 MAPK signaling.

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in silico ​studies were conducted to explore the binding of these ginsenosides to p38 MAPK and evidenced the promising their inhibitory effect.

Neuroprotective Effects of B-Type Cinnamon Procyanidin Oligomers on MPP+-Induced Apoptosis in a Cell Culture Model of Parkinson's Disease

Cinnamon procyanidin oligomers (CPOs) are water-soluble components extracted from cinnamon. This study aims to explore the neuroprotection of B-type CPO (CPO-B) against 1-methyl-4-phenylpyridinium (MPP⁺)-mediated cytotoxicity and the molecular mechanisms underlying its protection. The results demonstrated that CPO-B showed protection by increasing cell viability, attenuating an intracellular level of reactive oxygen species, downregulating cleaved caspase-3 expression, and upregulating the Bcl-2/Bax ratio. Moreover, CPO-B completely blocked the dephosphorylation of extracellular, signal-regulated kinase 1 and 2 (Erk1/2) caused by MPP⁺. Treatment with an Erk1/2 inhibitor, SCH772984, significantly abolished the neuroprotection of CPO-B against MPP⁺. Taken together, we demonstrate that CPO-B from cinnamon bark provided protection against MPP⁺ in cultured SH-SY5Y cells, and the potential mechanisms may be attributed to its ability to modulate the dysregulation between pro-apoptotic and anti-apoptotic proteins through the Erk1/2 signaling pathway. Our findings suggest that the addition of cinnamon to food or supplements might benefit patients with PD.

Ginsenoside Rb1 Alleviates Lipopolysaccharide-Induced Inflammatory Injury by Downregulating miR-222 in WI-38 Cells

Pneumonia is a serious respiratory tract infection disease in children, which threatens to the health or life of children patients. Ginsenoside Rb1 (Rb1) is a principle active ingredient extracted from the root of Panax notoginseng (Burk.) F.H. Chen with anti-inflammatory effect. Our study aimed to determine the effects and molecular mechanisms of Rb1 on lipopolysaccharide (LPS)-induced inflammatory injury of lung fibroblasts WI-38 cells. Cell viability and apoptosis were evaluated by CCK-8 and flow cytometry, respectively. The production of inflammatory cytokines were measured by ELISA and RT-qPCR. miR-222 expression was examined by RT-qPCR. The expression levels of the nuclear factor-kappa B (NF-κB) p65 and phosphorylated p65 were detected by western blot. We found that LPS stimulation induced WI-38 cell inflammatory injury by inhibiting cell viability, and inducing apoptosis and inflammatory cytokine production, while treatment with Rb1 significantly attenuated LPS-induced inflammatory injury in WI-38 cells. Additionally, Rb1 decreased LPS-induced upregulation of miR-222 and activation of the NF-κB pathway in WI-38 cells. Overexpression of miR-222 abolished the inhibitory effects of Rb1 on LPS-induced viability reduction, apoptosis, inflammatory cytokine production and activation of the NF-κB pathway. In conclusion, Rb1 alleviated LPS-induced inflammatory injury in WI-38 cells via downregulating miR-222 and inactivation of the NF-kB pathway.

Bioactive Herbal Extracts of Traditional Chinese Medicine Applied with the Biomaterials: For the Current Applications and Advances in the Musculoskeletal System

Traditional Chinese medicine (TCM) has demonstrated superior therapeutic effect for musculoskeletal diseases for thousands of years. Recently, the herbal extracts of TCM have received rapid advances in musculoskeletal tissue engineering (MTE). A literature review collecting both English and Chinese references on bioactive herbal extracts of TCM in biomaterial-based approaches was performed. This review provides an up-to-date overview of application of TCMs in the field of MTE, involving regulation of multiple signaling pathways in osteogenesis, angiogenesis, anti-inflammation, and chondrogenesis. Meanwhile, we highlight the potential advantages of TCM, opening the possibility of its extensive application in MTE. Overall, the superiority of traditional Chinese medicine turns it into an attractive candidate for coupling with advanced additive manufacturing technology.

Ketamine and Propofol Protect Neuron Cells from Oxygen-Glucose Deprivation-Induced Injury through SAPK/JNK Signalling Pathway

Ketamine and propofol are commonly used anaesthetic reagents. Recent research revealed that ketamine and propofol have an important role in cell survival. However, it remains unknown whether they affect the outcome of hypoxic-ischemic brain injury. To address this issue, we in this study investigated the effects of ketamine and propofol on the survival and proliferation of neuronal PC12 cells after exposure to oxygen-glucose deprivation- (OGD-) induced injury. PC12 cells were maintained under a 3-dimensional (3D) culture system to mimic a real physiological microenvironment. The cell injury was induced by 5% CO2 and 95% N2 for a different time point. MTT assay was used for the cell proliferation assay. The cell apoptosis was evaluated by annexin V and propidium iodide (PI) labeling, immunofluorescence staining, transmission electron microscopy (TEM), flow cytometry, and Western blot, respectively. Our results showed that PC12 cell apoptosis was significantly increased for up to 70% after the cells were treated with OGD for 24 hours and reduced to baseline at the 72-hour time point. However, pretreatment with ketamine and propofol significantly protected the cells from OGD-induced cell apoptosis, as evidenced by more expression of antiapoptotic Bcl-2 and lower expression of proapoptotic cleaved caspase-3, phosphor-SAPK/JNK, and phosphor-c-Jun than those of untreated control cells. Thus, we conclude that ketamine and propofol protected PC12 cells from OGD-induced cell apoptosis, at least partially through the SAPK/JNK signalling pathway.

Korean Red Ginseng alleviates dehydroepiandrosterone-induced polycystic ovarian syndrome in rats via its antiinflammatory and antioxidant activities

BACKGROUND

Beneficial effects of Korean Red Ginseng (KRG) on polycystic ovarian syndrome (PCOS) remains unclear.

METHODS

We examined whether pretreatment (daily from 2 hours before PCOS induction) with KRG extract in water (KRGE; 75 and 150 mg/kg/day, p.o.) could exert a favorable effect in a dehydroepiandrosterone (DHEA)-induced PCOS rat model.

RESULTS

Pretreatment with KRGE significantly inhibited the elevation of body and ovary weights, the increase in number and size of ovarian cysts, and the elevation of serum testosterone and estradiol levels induced by DHEA. Pretreatment with KRGE also inhibited macrophage infiltration and enhanced mRNA expression levels of chemokines [interleukin (IL)-8, monocyte chemoattractant protein-1), proinflammatory cytokines (IL-1β, IL-6), and inducible nitric oxide synthase in ovaries induced by DHEA. It also prevented the reduction in mRNA expression of growth factors (epidermal growth factor, transforming growth factor-beta (EGF, TGF-β)) related to inhibition of the nuclear factor kappa-light-chain-enhancer of activated B cell pathway and stimulation of the nuclear factor erythroid-derived 2-related factor 2 pathway. Interestingly, KRGE or representative ginsenosides (Rb1, Rg1, and Rg3(s)) inhibited the activity of inflammatory enzymes cyclooxygenase-2 and iNOS, cytosolic p-IkB, and nuclear p-nuclear factor kappa-light-chain-enhancer of activated B in lipopolysaccharide-induced RAW264.7 cells, whereas they increased nuclear factor erythroid-derived 2-related factor 2 nuclear translocation.

CONCLUSION

These results provide that KRGE could prevent DHEA-induced PCOS via antiinflammatory and antioxidant activities. Thus, KRGE may be used in preventive and therapeutic strategies for PCOS-like symptoms.

Panax notoginseng saponins and their applications in nervous system disorders: a narrative review

Panax notoginseng saponins (PNS), also called "sanqi" in Chinese, are the main active ingredients which are extracted from the root of Panax notoginseng (Burk.) F. H. Chen., and they have been traditionally used as a medicine in China for hundreds of years with magical medicinal value. PNS have varied biological functions, such as anti-inflammatory effects, anti-cancer effects, anti-neurotoxicity, and the prevention of diabetes. Nervous system disorders, a spectrum of diseases originating from the nervous system, have a significant impact on all aspects of patients' lives. Due to the dramatic gains in global life expectancy, the prevalence of nervous system disorders is growing gradually. Even if the mechanism of these diseases is still not clear, they are mainly characterized by neuronal dysfunction and neuronal death. Consequently, it is essential to find measures to slow down or prevent the onset of these diseases. At present, traditional Chinese medicines, as well as their active components, have gained widespread popularity in preventing and treating these diseases because of their merits, especially PNS. In this review, we predominantly address the recent advances in PNS researches and their biological functions, and highlight their applications in nervous system disorders, such as Alzheimer's disease (AD), Parkinson's disease (PD), and stroke.

Ginsenoside Rb1/TGF-β1 loaded biodegradable silk fibroin-gelatin porous scaffolds for inflammation inhibition and cartilage regeneration

Creating a microenvironment with low inflammation and favorable for the chondrogenic differentiation of endogenous stem cells plays an essential role in cartilage repairing. In the present study, we design a novel ginsenoside Rb1/TGF-β1 loaded silk fibroin-gelatin porous scaffold (GSTR) with the function of attenuating inflammation and promoting chondrogenesis. The scaffold has porous microstructure, proper mechanical strength, degradation rate and sustained release of Rb1 and TGF-β1. Rat bone marrow-derived mesenchymal stem cells (rBMSCs) seeded into GSTR scaffolds are homogeneously distributed and display a higher proliferation rate than non-loaded scaffolds (GS). GSTR scaffolds promote the chondrogenic differentiation of rBMSCs and suppress the expression of inflammation genes. Under the stimulation of IL-1β, the inflammation level of the chondrocytes seeded in GSTR scaffolds is also significantly down-regulated. Moreover, GSTR scaffolds implanted into the osteochondral defects in rats effectively promote the regeneration of hyaline cartilage 12 weeks after surgery when compared with other groups. It is demonstrated that this scaffold loaded with Rb1 and TGF-β1 can synergistically create a microenvironment favorable for cartilage regeneration by promoting the chondrogenesis and suppressing the inflammation levels in vivo. These results prove it has a great potential to develop this Rb1/TGF-β1 releasing scaffold into a novel and promising therapeutic for cartilage repair.

Ginsenoside Rb1 inhibits monoiodoacetate-induced osteoarthritis in postmenopausal rats through prevention of cartilage degradation

Background

Ginsenoside Rb1 (G-Rb1), one of the major active compounds in Panax ginseng, has already been shown to reduce inflammation in various diseases. Osteoarthritis (OA) has traditionally been considered a degenerative disease with degradation of joint articular cartilage. However, recent studies have shown the association of inflammation with OA. In the present study, we investigated whether Rb1 had an antiinflammatory effect on monoiodoacetate (MIA)-induced OA in ovariectomized rats as a model of postmenopausal arthritis.

Methods

G-Rb1 at a dosage of 3 and 10 μg/kg body weight was administered every 3 days intraarticularly for a period of 4 weeks to observe antiarthritic effects. Diclofenac (10 mg/kg) served as a positive control.

Results

The administration of Rb1 significantly ameliorated OA inflammatory symptoms and reduced serum levels of inflammatory cytokines. Furthermore, G-Rb1 administration considerably enhanced the expression of bone morphogenetic protein-2 and collagen 2A and reduced the levels of matrix metalloproteinase-13 genes, indicating a chondroprotective effect of G-Rb1. G-Rb1 also significantly reduced the expression of several inflammatory cytokines/chemokines (interferon gamma (IFN-γ), monocyte chemoattractant protein-1 (MCP-1)/CCL-2, interleukin [IL]-1β, and IL-6). Histological analysis demonstrated that G-Rb1 significantly attenuated the pathological changes in MIA-induced OA in ovariectomized rats. Safranin O and toluidine blue staining further demonstrated that G-Rb1 effectively prevented the degradation of cartilage and glycosaminoglycans, respectively.

Conclusion

Overall, our results suggest that G-Rb1 exerts cartilage protective effect on MIA-induced ovariectomized OA rats, by inhibiting inflammatory mediators such as IL-6, IL-1β, MCP-1/CCL-2, cyclooxygenase-2 (COX-2), and prostaglandin E₂ (PGE2). These results shed a light on possible therapeutic application of G-Rb1 in OA.

Ginsenoside Re Mitigates 6-Hydroxydopamine-Induced Oxidative Stress through Upregulation of GPX4

Ginsenosides are active components found abundantly in ginseng which has been used as a medicinal herb to modify disease status for thousands of years. However, the pharmacological activity of ginsenoside Re in the neuronal system remains to be elucidated. Neuroprotective activity of ginsenoside Re was investigated in SH-SY5Y cells exposed to 6-hydroxydopamine (6-OHDA) to induce cellular injury. Ginsenoside Re significantly inhibited 6-OHDA-triggered cellular damage as judged by analysis of tetrazolium dye reduction and lactose dehydrogenase release. In addition, ginsenoside Re induced the expression of the antioxidant protein glutathione peroxidase 4 (GPX4) but not catalase, glutathione peroxidase 1, glutathione reductase, or superoxide dismutase-1. Furthermore, upregulation of GPX4 by ginsenoside Re was mediated by phosphoinositide 3-kinase and extracellular signal-regulated kinase but not by p38 mitogen-activated protein kinase or c-Jun N-terminal kinase. Ginsenoside Re also suppressed 6-OHDA-triggered cellular accumulation of reactive oxygen species and peroxidation of membrane lipids. The GPX4 inhibitor (1S,3R)-RSL3 reversed ginsenoside Re-mediated inhibition of cellular damage in SH-SY5Y cells exposed to 6-OHDA, indicating that the neuronal activity of ginsenoside Re is due to upregulation of GPX4. These findings suggest that ginsenoside Re-dependent upregulation of GPX4 reduces oxidative stress and thereby alleviates 6-OHDA-induced neuronal damage.

Ginsenoside Rb1 promotes intestinal epithelial wound healing through extracellular signal-regulated kinase and Rho signaling

BACKGROUND AND AIM

Daikenchuto, a traditional Japanese herbal medicine, has been reported to exhibit anti-inflammatory effects against intestinal inflammation. However, whether daikenchuto has a therapeutic effect against intestinal mucosal injuries remains unclear. Thus, the aim of this study was to determine the effect of daikenchuto on intestinal mucosal healing.

METHODS

Colitis was induced in male Wistar rats by using trinitrobenzenesulfonic acid. Daikenchuto (900 mg/kg/day) was administered for 7 days after the induction of colitis. Thereafter, intestinal mucosal injuries were evaluated by determining the colonic epithelial regeneration ratio ([area of epithelial regeneration/area of ulcer] × 100). Restoration of rat intestinal epithelial cells treated with daikenchuto and its constituent herbs (Zanthoxylum fruit, processed ginger, and ginseng) and ginsenoside Rb1, which is a ginseng ingredient, was evaluated using a wound-healing assay.

RESULTS

The colon epithelial regeneration ratio in the daikenchuto-treated rats was significantly higher than that in the control rats. Daikenchuto, ginseng, and ginsenoside Rb1 enhanced wound healing, and the ginsenoside Rb1-induced enhancement was inhibited by extracellular signal-regulated kinase and Rho inhibitors.

CONCLUSIONS

Daikenchuto and its constituent, ginsenoside Rb1, promoted wound healing. Because mucosal healing is one of the most important therapeutic targets in patients with inflammatory bowel disease, ginsenoside Rb1 may be a novel therapeutic agent against intestinal mucosal damage such as that occurring in intestinal bowel disease.

Ginsenoside Rb1 Blocks Ritonavir-Induced Oxidative Stress and eNOS Downregulation through Activation of Estrogen Receptor-Beta and Upregulation of SOD in Human Endothelial Cells

We have previously shown that ritonavir (RTV), a highly active anti-retroviral therapy (HAART) drug, can cause endothelial dysfunction through oxidative stress. Several antioxidants including ginsenoside Rb1, a compound with antioxidant effect, can effectively block this side effect of RTV in endothelial cells. In the current study, we explored a mechanism by which ginsenoside Rb1 could protect these cells via binding of estrogen receptors (ERs). We found that several human endothelial cell lines differentially expressed ER-β and had very low levels of ER-α. RTV treatment significantly increased the production of reactive oxygen species (ROS) and decreased the expression of endothelial nitric oxidase synthase (eNOS) and superoxide dismutase (SOD) in HUVECs, while Rb1 effectively blocked these effects of RTV. These effects of Rb1 were effectively inhibited by silencing ER-β, indicating that ginsenoside Rb1 requires ER-β for its antioxidant activity in inhibiting the deleterious effect of RTV in human endothelial cells. Furthermore, Rb1 specifically activated ER-β transactivation activity by ER-β luciferase reporter assay. Rb1 competitively bound to ER-β, which was determined by the high sensitive fluorescent polarization assay.

Ginsenoside Rb1 protects dopaminergic neurons from inflammatory injury induced by intranigral lipopolysaccharide injection

Accumulating studies suggest that neuroinflammation characterized by microglial overactivation plays a pivotal role in the pathogenesis of Parkinson’s disease. As such, inhibition of microglial overactivation might be a promising treatment strategy to delay the onset or slow the progression of Parkinson’s disease. Ginsenoside Rb1, the most active ingredient of ginseng, reportedly exerts neuroprotective effects by suppressing inflammation in vitro. The present study aimed to evaluate the neuroprotective and anti-inflammatory effects of ginsenoside Rb1 in a lipopolysaccharide-induced rat Parkinson’s disease model. Rats were divided into four groups. In the control group, sham-operated rats were intraperitoneally administered normal saline for 14 consecutive days. In the ginsenoside Rb1 group, ginsenoside Rb1 (20 mg/kg) was intraperitoneally injected for 14 consecutive days after sham surgery. In the lipopolysaccharide group, a single dose of lipopolysaccharide was unilaterally microinjected into the rat substantial nigra to establish the Parkinson’s disease model. Lipopolysaccharide-injected rats were treated with normal saline for 14 consecutive days. In the ginsenoside Rb1 + lipopolysaccharide group, lipopolysaccharide was unilaterally microinjected into the rat substantial nigra. Subsequently, ginsenoside Rb1 was intraperitoneally injected for 14 consecutive days. To investigate the therapeutic effects of ginsenoside Rb1, behavioral tests were performed on day 15 after lipopolysaccharide injection. We found that ginsenoside Rb1 treatment remarkably reduced apomorphine-induced rotations in lipopolysaccharide-treated rats compared with the lipopolysaccharide group. To investigate the neurotoxicity of lipopolysaccharide and potential protective effect of ginsenoside Rb1, contents of dopamine and its metabolites in the striatum were measured by high-performance liquid chromatography. Compared with the lipopolysaccharide group, ginsenoside Rb1 obviously attenuated the lipopolysaccharide-induced depletion of dopamine and its metabolites in the striatum. To further explore the neuroprotective effect of ginsenoside Rb1 against lipopolysaccharide-induced neurotoxicity, immunohistochemistry and western blot assay of tyrosine hydroxylase were performed to evaluate dopaminergic neuron degeneration in the substantial nigra par compacta. The results showed that lipopolysaccharide injection caused a large loss of tyrosine hydroxylase-immunoreactive neurons in the substantia nigra and a significant decrease in overall tyrosine hydroxylase expression. However, ginsenoside Rb1 noticeably reversed these changes. To investigate whether the neuroprotective effect of ginsenoside Rb1 was associated with inhibition of lipopolysaccharide-induced microglial activation, we examined expression of the microglia marker Iba-1. Our results confirmed that lipopolysaccharide injection induced a significant increase in Iba-1 expression in the substantia nigra; however, ginsenoside Rb1 effectively suppressed lipopolysaccharide-induced microglial overactivation. To elucidate the inhibitory mechanism of ginsenoside Rb1, we examined expression levels of inflammatory mediators (tumor necrosis factor-α, interleukin-1β, inducible nitric oxide synthase, and cyclooxygenase 2) and phosphorylation of nuclear factor kappa B signaling-related proteins (IκB, IKK) in the substantia nigra with enzyme-linked immunosorbent and western blot assays. Our results revealed that compared with the control group, phosphorylation and expression of inflammatory mediators IκB and IKK in the substantia nigra of lipopolysaccharide group rats were significantly increased; whereas, ginsenoside Rb1 obviously reduced lipopolysaccharide-induced changes on the lesioned side of the substantial nigra par compacta. These findings confirm that ginsenoside Rb1 can inhibit inflammation induced by lipopolysaccharide injection into the substantia nigra and protect dopaminergic neurons, which may be related to its inhibition of the nuclear factor kappa B signaling pathway. This study was approved by the Experimental Animal Ethics Committee of Shandong University of China in April 2016 (approval No. KYLL-2016-0148).

Effects of Ginsenoside Rb1 on Expressions of Phosphorylation Akt/Phosphorylation mTOR/Phosphorylation PTEN in Artificial Abnormal Hippocampal Microenvironment in Rats

Artificial abnormal microenvironment caused by microperfusion of L-glutamate (Glu) and Ca²⁺ in the hippocampus results in neuron damage, which is closely related to cerebral ischemia. Ginsenoside Rb1, a compound from Panax notoginseng, was previously used to counter the artificial abnormal hippocampal environment in a microperfusion model. In addition, while the Akt/mTOR/PTEN signaling pathway has been shown to mediate neuronprotection in cerebral ischemia, whether this pathway is involved in the neuroprotection of ginsenoside Rb1 is unknown. Here SH-SY5Y cells exposed to OGD/R injury in treated with LY294002, ginsenoside Rb1, ginsenoside Rb1+ LY294002. Expressions of phosphorylation (P-)Akt/P-mTOR/P-PTEN (24 h after OGD/R) were detected by Western blotting. Effects were examined via the memory function of rats (by Morris water maze test), morphological changes in pyramidal cell (by histology), and mRNA expression (by qRT-PCR) and phosphorylation (P-) (by Western blotting and immunohistochemical staining) of Akt, P-mTOR, and P-PTEN in the hippocampus. The memory deficit of rats and pyramidal cellular necrosis and apoptosis in the CA1 region of hippocampus after microperfusion of Glu and Ca²⁺ were dose dependently alleviated by ginsenoside Rb1.Moreover,Western blot showed that ginsenoside Rb1 increased the expressions of P-Akt, P-mTOR and reduced P-PTEN in vivo and vitro. Thus, the potent neuroprotection of ginsenoside Rb1 in artificial abnormal microenvironment is, at least partially, related to the activation of P-AKT/P-mTOR signaling pathway and inhibition of P-PTEN protein.

Protective Effects of Ginsenoside Rb1 against Blood-Brain Barrier Damage Induced by Human Immunodeficiency Virus-1 Tat Protein and Methamphetamine in Sprague-Dawley Rats

Although antiretroviral therapy has helped to improve the lives of individuals infected with human immunodeficiency virus 1 (HIV-1), these patients are often still afflicted with HIV-1-associated neurocognitive disorders, which can lead to neurocognitive impairment and even dementia, and continue to hamper their quality of life. Methamphetamine abuse in HIV-1 patients poses a potential risk for HIV-associated neurocognitive disorders, because methamphetamine and HIV-1 proteins such as transactivator of transcription can synergistically damage the blood-brain barrier (BBB). In this study, we aimed to examine the effects of methamphetamine and HIV-1 Tat protein on the blood-brain barrier function and to determine whether ginsenoside Rb1 (GsRb1) plays a role in protecting the BBB. Sprague-Dawley rats were divided into four groups. The experimental groups received methamphetamine and HIV-1 Tat protein or both and the control group received saline or GsRb1 pretreatment. Oxidative stress-related factors, tight junction (TJ) proteins, blood-brain barrier permeability, and morphological changes were recorded in each group. The results showed that the group treated with Methamphetamine[Formula: see text]Tat showed a significant change at the ultrastructural level and in the levels of oxidative stress-related factors, TJ proteins, and BBB permeability, suggesting that the BBB function was severely damaged by HIV-1 Tat and methamphetamine synergistically. However, malondialdehyde levels and BBB permeability were lower and the oxidative stress-related factors superoxide dismutase and glutathione were higher in the GsRb1-treated group than in the Methamphetamine[Formula: see text]Tat-treated group, indicating that GsRb1 can protect the BBB against the toxic effects of HIV-1 Tat and methamphetamine. These results show that GsRb1 may offer a potential therapeutic option for patients with HIV-associated neurocognitive disorders or other neurodegenerative diseases.

Emerging signals modulating potential of ginseng and its active compounds focusing on neurodegenerative diseases

Common features of neurodegenerative diseases (NDDs) include progressive dysfunctions and neuronal injuries leading to deterioration in normal brain functions. At present, ginseng is one of the most frequently used natural products. Its use has a long history as a cure for various diseases because its extracts and active compounds exhibit several pharmacological properties against several disorders. However, the pathophysiology of NDDs is not fully clear, but researchers have found that various ion channels and specific signaling pathways might have contributed to the disease pathogenesis. Apart from the different pharmacological potentials, ginseng and its active compounds modulate various ion channels and specific molecular signaling pathways related to the nervous system. Here, we discuss the signal modulating potential of ginseng and its active compounds mainly focusing on those relevant to NDDs.

Therapeutic Potential and Cellular Mechanisms of Panax Notoginseng on Prevention of Aging and Cell Senescence-Associated Diseases

Owing to a dramatic increase in average life expectancy, most countries in the world are rapidly entering an aging society. Therefore, extending health span with pharmacological agents targeting aging-related pathological changes, are now in the spotlight of gerosciences. Panax notoginseng (Burk.) F. H. Chen, a species of the genus Panax, has been called the "Miracle Root for the Preservation of Life," and has long been used as a Chinese herb with magical medicinal value. Panax notoginseng has been extensively employed in China to treat microcirculatory disturbances, inflammation, trauma, internal and external bleeding due to injury, and as a tonic. In recent years, with the deepening of the research pharmacologically, many new functions have been discovered. This review will introduce its pharmacological function on lifespan extension, anti-vascular aging, anti-brain aging, and anti-cancer properties, aiming to lay the ground for fully elucidating the potential mechanisms of Panax notoginseng's anti-aging effect to promote its clinical application.

Estrogenic terpenes and terpenoids: Pathways, functions and applications

Terpenes are made of the isoprene unit (C₅), and along with their derivatives, terpenoids, they are widely distributed in plants as active ingredients involved in anti-inflammation, anti-carcinogenesis and neuroprotection. Estrogenic terpenes and terpenoids are an important category of phytoestrogens and have been used as traditional medicines. The comprehensive list of estrogenic terpenes and terpenoids includes hemi-, mono-, sesqui-, di-, tri-, tetra- and polyterpenes, their derivatives, and meroterpenes, along with the signaling pathways and cellular functions on which their estrogenicity is exerted. Signaling pathways are further classified as bidirectional or unidirectional, the latter being further divided into two types depending upon the presence of both ligands, or the absence of one or both ligands. Although estrogenic activity of terpenes and terpenoids was evaluated by ligand-binding assays, yeast two-hybrid assays, reporter-gene assays, transcription assays, protein assays, cell assays and animal testing, the mechanism of estrogenic activity is still not fully understood. Applications of estrogenic terpenes and terpenoids are categorized into cancer treatment and prevention, cardioprotection, endocrine toxicity/reproductive dysfunction, food/supplement/traditional medicine, immunology/inflammation, menopausal syndromes and neuroprotection, where their benefits are discussed based on their availability, stability and variations.

Purinergic receptor P2Y6 contributes to 1-methyl-4-phenylpyridinium-induced oxidative stress and cell death in neuronal SH-SY5Y cells

Oxidative stress and neural degeneration have been shown to be involved in the pathogenesis of Parkinson's disease (PD). The P2Y6 purinergic receptor (P2Y6R) has been shown to participate in the activation of microglia and the production of pro-inflammatory factors induced by lipopolysaccharide to cause neuronal loss. However, the function of P2Y6R during oxidative stress in neurons is unclear. In the present study, 1-methyl-4-phenylpyridinium (MPP⁺ ) treatment increased the level of UDP/P2Y6R on neuronal SH-SY5Y cells. Importantly, pharmacological inhibition of P2Y6R or knockdown of P2Y6R using a siRNA exerted an increased protective effect by preventing MPP⁺ -induced increases in the levels of reactive oxygen species (ROS), superoxide anion, inducible nitric oxide synthase (iNOS), and malondialdehyde (MDA) and down-regulation of superoxide dismutase 1 (SOD1) expression. UDP, an agonist of P2Y6R, enhanced the effects of MPP⁺ , which was also inhibited by apyrase or MRS2578. Additionally, P2Y6R knockdown also significantly reversed both the loss of cell viability and the increase in the levels of phosphorylated extracellular signal-regulated protein kinase (p-ERK1/2) and p38 (p-p38) caused by MPP⁺ stimulation. However, the inhibition of the ERK1/2 and p38 kinase signaling pathways had no effect on P2Y6R expression. Taken together, these results support the hypothesis that P2Y6R expressed on neuronal SH-SY5Y cell is associated with the progression of oxidative stress and cell death induced by MPP⁺ , suggesting that P2Y6R may play an important role in the pathogenesis of PD.

Effect of a Traditional Chinese Herbal Medicine Formulation on Cell Survival and Apoptosis of MPP+-Treated MES 23.5 Dopaminergic Cells

Progressive degeneration of dopaminergic neurons in the substantia nigra (SN) is implicated in Parkinson's disease (PD). The efficacy of these currently used drugs is limited while traditional Chinese medicine (TCM) has been used in the management of neurodegenerative diseases for many years. This study was designed to evaluate the effect of a modified traditional Chinese herbal medicine decoction, Cong Rong Jing (CRJ), on cell survival and apoptosis of 1-methyl-4-phenylpyridinium- (MPP⁺-) treated MES23.5 dopaminergic cells. CRJ was prepared as a decoction from three Chinese herbs, namely, Herba Cistanches, Herba Epimedii, and Rhizoma Polygonati. We reported here that CRJ significantly enhanced the cell survival of MES23.5 cells after the exposure of MPP⁺ and inhibited the production of intracellular reactive oxygen species (ROS) induced by MPP⁺. CRJ also prevented the MPP⁺-treated MES23.5 cells from apoptosis by reducing the externalization of phosphatidylserine and enhancing the Bcl-2/Bax protein expression ratio. Signaling proteins such as JAK2, STAT3, and ERK1/2 were also involved in the action of CRJ. Taken together, these results provide a preliminary mechanism to support clinical application of the TCM formulation in PD and possibly other neurodegenerative diseases associated with ROS injury and apoptosis.

Pre-treatment with amitriptyline causes epigenetic up-regulation of neuroprotection-associated genes and has anti-apoptotic effects in mouse neuronal cells

Antidepressants, such as imipramine and fluoxetine, are known to alter gene expression patterns by inducing changes in the epigenetic status of neuronal cells. There is also some evidence for the anti-apoptotic effect of various groups of antidepressants; however, this effect is complicated and cell-type dependent. Antidepressants of the tricyclic group, in particular amitriptyline, have been suggested to be beneficial in the treatment of neurodegenerative disorders. We examined whether amitriptyline exerts an anti-apoptotic effect via epigenetic mechanisms. Using DNA microarray, we analyzed global gene expression in mouse primary cultured neocortical neurons after treatment with amitriptyline and imipramine. The neuroprotection-associated genes, activating transcription factor 3 (Atf3) and heme oxygenase 1 (Hmox1), were up-regulated at both mRNA and protein levels by treatment with amitriptyline. Quantitative chromatin immunoprecipitation assay revealed that amitriptyline increased enrichments of trimethylation of histone H3 lysine 4 in the promoter regions of Atf3 and Hmox1 and acetylation of histone H3 lysine 9 in the promoter regions of Atf3, which indicate an active epigenetic status. Amitriptyline pre-treatment attenuated 1-methyl-4-phenylpyridinium ion (MPP⁺)- or amyloid β peptide 1-42 (Aβ_1-42)-induced neuronal cell death and inhibited the activation of extracellular signal-regulated kinase 1 and 2 (ERK1/2). We found that Atf3 and Hmox1 were also up-regulated after Aβ_1-42 treatment, and were further increased when pre-treated with amitriptyline. Interestingly, the highest up-regulation of Atf3 and Hmox1, at least at mRNA level, was observed after co-treatment with Aβ_1-42 and amitriptyline, together with the loss of the neuroprotective effect. These findings suggest preconditioning and neuroprotective effects of amitriptyline; however, further investigations are needed for clarifying the contribution of epigenetic up-regulation of Atf3 and Hmox1 genes.

Ginsenoside Rb1 protects against ischemia/reperfusion-induced myocardial injury via energy metabolism regulation mediated by RhoA signaling pathway

Cardiac ischemia and reperfusion (I/R) injury remains a challenge for clinicians. Ginsenoside Rb1 (Rb1) has been reported to have the ability to attenuate I/R injury, but its effect on energy metabolism during cardiac I/R and the underlying mechanism remain unknown. In this study, we detected the effect of Rb1 on rat myocardial blood flow, myocardial infarct size, cardiac function, velocity of venule red blood cell, myocardial structure and apoptosis, energy metabolism and change in RhoA signaling pathway during cardiac I/R injury. In addition, the binding affinity of RhoA to Rb1 was detected using surface plasmon resonance (SPR). Results showed that Rb1 treatment at 5 mg/kg/h protected all the cardiac injuries induced by I/R, including damaged myocardial structure, decrease in myocardial blood flow, impaired heart function and microcirculation, cardiomyocyte apoptosis, myocardial infarction and release of myocardial cTnI. Rb1 also inhibited the activation of RhoA signaling pathway and restored the production of ATP during cardiac I/R. Moreover, SPR assay showed that Rb1 was able to bind to RhoA in a dose-dependent manner. These results indicate that Rb1 may prevent I/R-induced cardiac injury by regulation of RhoA signaling pathway, and may serve as a potential regime to improve percutaneous coronary intervention outcome.

Shengmai injection attenuates the cerebral ischemia/reperfusion induced autophagy via modulation of the AMPK, mTOR and JNK pathways

Context Shengmai injection (SMI) is a patented Chinese medicine originated from the ancient Chinese herbal compound Shengmai san, which is used extensively for the treatment of cardiovascular and cerebrovascular disease in the clinic. Objective To determine the neuroprotective effect of SMI, we investigated the effect of SMI on cerebral ischemia/reperfusion (I/R) injury in mice as well as the mechanisms underlying this effect. Materials and methods Right middle cerebral artery was occluded by inserting a thread through internal carotid artery for 1 h, and then reperfused for 24 h in mice. The neuroprotective effects were determined using transmission electron microscopic examination, the evaluation of infarct volume, neurological deficits and water brain content. Related mechanisms were evaluated by immunofluorescence staining and western blotting. SMI was injected intraperitoneally after 1 h of ischemia at doses of 1.42, 2.84 and 5.68 g/kg. The control group received saline as the SMI vehicle. Results Results showed that SMI (1.42, 2.84 and 5.68 g/kg) could significantly reduce the infarct volume, SMI (5.68 g/kg) could also significantly improve the neurological deficits, decreased brain water content, as well as the neuronal morphological changes. SMI (5.68g/kg) could significantly inhibit the expression of autophagy-related proteins: Beclin1 and LC3. It also reduced the increase in LC3-positive cells. SMI (5.68 g/kg) remarkably inhibited the phosphorylation of adenosine monophosphate activated protein kinase (AMPK), and down-regulated the phosphorylation of mammalian target of rapamycin (mTOR) and Jun N-terminal kinase (JNK) after 24 h of reperfusion. Discussion and conclusion The results indicate that SMI provides remarkable protection against cerebral ischemia/reperfusion injury, which may be partly due to the inhibition of autophagy and related signalling pathways.

Involvement of Connexin40 in the Protective Effects of Ginsenoside Rb1 Against Traumatic Brain Injury

Ginsenosides are the major active components of ginseng, which have been proven to be effective in therapies for neurodegenerative diseases. Ginsenoside Rb1 (GS-Rb1) is the most abundant among all the identified ginsenosides and has been shown to exert neuroprotective effects, although the underlying molecular mechanisms remain unclear. Connexins are a family of transmembrane proteins that form gap junctions, which are important for diffusion of cytosolic factors such as ions and second messenger signaling molecules. Previous studies have shown that a subset of connexin proteins is involved in neuroprotection. We investigated the protective effects of GS-Rb1 against traumatic brain injury (TBI) and the potential mechanism using TBI mouse model. We discovered that TBI-induced brain injury and up-regulation of connexin40 (Cx40) protein expression as early as 6 h post-TBI, which was reversed by administration of GS-Rb1. In addition, we found that the protective effects of GS-Rb1 are dose and time dependent and are partially mediated through phosphorylation of ERK1/2 signaling pathway, as evidenced by the abolishment of GS-Rb1-mediated elevation of p-ERK1/2 expression and inhibition of Cx40 expressions when ERK inhibitor U0126 was used. Our study provides evidence that Cx40 is implicated in TBI-induced brain injuries, and GS-Rb1 exerts neuroprotective activity against TBI involving down-regulation of Cx40 expression.

Effects of ginseng on two main sex steroid hormone receptors: estrogen and androgen receptors

Ginseng has been used in China for at least two millennia and is now popular in over 35 countries. It is one of the world's popular herbs for complementary and alternative medicine and has been shown to have helpful effects on cognition and blood circulation, as well as anti-aging, anti-cancer, and anti-diabetic effects, among many others. The pharmacological activities of ginseng are dependent mainly on ginsenosides. Ginsenosides have a cholesterol-like four trans-ring steroid skeleton with a variety of sugar moieties. Nuclear receptors are one of the most important molecular targets of ginseng, and reports have shown that members of the nuclear receptor superfamily are regulated by a variety of ginsenosides. Here, we review the published literature on the effects of ginseng and its constituents on two main sex steroid hormone receptors: estrogen and androgen receptors. Furthermore, we discuss applications for sex steroid hormone receptor modulation and their therapeutic efficacy.

Translational potential of ginsenoside Rb1 in managing progression of osteoarthritis

BACKGROUND

Osteoarthritis (OA) is the most common degenerative joint disorder. Inflammatory cytokine plays an important role in OA progression. Previous studies have demonstrated that ginsenoside Rb1 would prevent inflammation and apoptosis in chondrocytes. However, we have not found any animal study reporting that Rb1 attenuates the severity of OA.

OBJECTIVE

In this study, we used a rat anterior cruciate ligament transaction plus medial meniscus resection (ACLT + MMx) model of OA and a cell model, to investigate whether administration of ginsenoside Rb1 may attenuate the progression of arthritis.

METHODS

In this in vivo study, 16-week-old male Sprague-Dawley rats were divided into three groups: Group 1 (sham control group), Group 2 (Rb1-treated group), and Group 3 (OA group). In Groups 2 and 3, OA was induced in the right knee joint with ACLT + MMx in rats. Then Group 2 received continuous infusion of ginsenoside Rb1 via osmotic mini-pumps implanted subcutaneously. At 4 weeks after treatment, the rats were sacrificed. Interleukin-1β (IL-1β) level was evaluated by enzyme-linked immunosorbent assay (ELISA); cartilage damage was assessed via histology (Safranin-O/fast green stain) and immunohistochemistry [matrix metalloproteinase-13 (MMP13) and type X collagen (Col X)]. For cell study, C5.18 (rat chondrocyte cell line) was used in this research. The effect of Rb1 on IL-1β-induced MMP13 or Col X expression level in C5.18 cells was investigated.

RESULTS

In this in vivo study, characteristics of OA were present in the OA group, in contrast to less severe damage generally observed in the Rb1 treatment group: first, IL-1β level was significantly decreased, and second, cartilage degeneration was attenuated, as indicated by lower histologic damage scores and lower percentages of MMP13 or Col X-positive chondrocytes. In the cell study, the results showed that Rb1 treatment would relieve the MMP13 or Col X expression in C5.18 cells induced by IL-1β.

CONCLUSION

In the present study, we demonstrated that Rb1 can attenuate the progression or severity of arthritis by reducing inflammation.

Protective effects of PEP-1-Catalase on stress-induced cellular toxicity and MPTP-induced Parkinson's disease

Parkinson's disease (PD) is a neurodegenerative disability caused by a decrease of dopaminergic neurons in the substantia nigra (SN). Although the etiology of PD is not clear, oxidative stress is believed to lead to PD. Catalase is antioxidant enzyme which plays an active role in cells as a reactive oxygen species (ROS) scavenger. Thus, we investigated whether PEP-1-Catalase protects against 1-methyl-4-phenylpyridinium (MPP+) induced SH-SY5Y neuronal cell death and in a 1-methyl- 4-phenyl-1,2,3,6-trtrahydropyridine (MPTP) induced PD animal model. PEP-1-Catalase transduced into SH-SY5Y cells significantly protecting them against MPP+-induced death by decreasing ROS and regulating cellular survival signals including Akt, Bax, Bcl-2, and p38. Immunohistochemical analysis showed that transduced PEP-1-Catalase markedly protected against neuronal cell death in the SN in the PD animal model. Our results indicate that PEP-1-Catalase may have potential as a therapeutic agent for PD and other oxidative stress related diseases.

Ginsenoside Rg3 prevents INS-1 cell death from intermittent high glucose stress

BACKGROUND

Ginsenoside Rg3 has been proposed to mediate anti-diabetic effects, but their direct effect on pancreatic β cell viability and mechanisms are not clearly understood. Recent studies suggest that intermittent high glucose (IHG) could be more harmful to pancreatic β cells than sustained high glucose. There are few reports about the effect of the ginsenosideRg3 to β cell apoptosis and proliferation against IHG.

METHODS

INS-1 cells were treated with alternative glucose concentration with or without ginsenoside Rg3. Cell apoptosis and viability were detected by Annexin V staining and MTT assay. The activation of mitogen-activated protein kinases (MAPKs) was analyzed by Western blotting using specific antibodies. Quantification of secreted insulin protein was measured using rat/mouse Insulin ELISA kits. Bromodeoxyuridine (BrdU) staining and florescence in situ hybridization (FISH) analysis was performed to compare cell proliferation.

RESULT

INS-1 cell viability was decreased under IHG and increased with Rg3 treatment.Rg3 significantly reduced the apoptotic INS-1 cells against IHG. The quantification of secreted insulin concentration was increased with Rg3. Rg3 increased INS-1 cell proliferation. ERK and p38 MAPK pathways reduced by IHG were activated by the ginsenoside Rg3.

CONCLUSION

Ginsenoside Rg3 protected INS-1 cell death from IHG with reducing apoptosis and increasing proliferation.

MiR-133b ameliorates axon degeneration induced by MPP(+) via targeting RhoA

Increasing evidence suggests that microRNAs (miRs) play a significant role in the pathogenesis of Parkinson's disease (PD). MiR-133b, which is significantly decreased in the PD midbrain, has recently been shown to promote neurite outgrowth and enhance neural functional recovery. However, the role of miR-133b in PD has not been clearly established. Here, using a well-established PD model culture based on the neurotoxin 1-methyl-4-phenyl-pyridinium (MPP(+)), we demonstrated that miR-133b could promote axon outgrowth in dopaminergic neurons (DNs) and ameliorated MPP(+)-induced axon degeneration. Additional experiments suggested that the mechanisms of this miR-133b-mediated effect might rely on RhoA inhibition. We demonstrated that RhoA, an inhibitor of axonal growth, was increased in DNs under MPP(+) treatment, and this increase could be attenuated by miR-133b overexpression. Moreover, we demonstrated that the induced expression of miR-133b could inhibit α-synuclein, which is critically involved in the pathological process of PD. Furthermore, we found that overexpression of miR-133b abrogated the MPP(+)-induced decrease in the Bcl-2/Bax ratio and upregulated phosphorylated Akt (p-Akt), which is a pro-survival kinase. Together these findings reveal novel roles for miR-133b in the pathogenesis of PD and provide new therapeutic avenues for the treatment of the disease.

Neuroprotective effects of ginsenosides on neural progenitor cells against oxidative injury

Ginsenosides exhibit various neuroprotective effects against oxidative stress. However, which ginsenoside provides optimal effects for the treatment of neurological disorders as a potent antioxidant remains to be elucidated. Therefore, the present study investigated and compared the neuroprotective effects of the Rb1, Rd, Rg1 and Re ginsenosides on neural progenitor cells (NPCs) following tert-Butylhydroperoxide (t-BHP)-induced oxidative injury. Primary rat embryonic cortical NPCs were prepared from E14.5 embryos of Sprague-Dawley rats. The oxidative injury model was established with t-BHP. A lactate dehydrogenase assay and terminal deoxynucleotidyl transferase dUTP nick-end labeling staining were used to measure the viability of the NPCs pre-treated with ginsenosides under oxidative stress. Reverse transcription-quantitative polymerase chain reaction analysis was used to determine the activation of intracellular signaling pathways triggered by the pretreatment of ginsenosides. Among the four ginsenosides, only Rb1 attenuated t-BHP toxicity in the NPCs, and the nuclear factor (erythroizd-derived 2)-like 2/heme oxygenase-1 pathway was found to be key in the intracellular defense against oxidative stress. The present study demonstrated the anti-oxidative effects of ginsenoside Rb1 on NPCs, and suggested that Rb1 may offer potential as a potent antioxidant for the treatment of neurological disorders.

Estrogenic endocrine disruptors: Molecular mechanisms of action

A comprehensive summary of more than 450 estrogenic chemicals including estrogenic endocrine disruptors is provided here to understand the complex and profound impact of estrogen action. First, estrogenic chemicals are categorized by structure as well as their applications, usage and effects. Second, estrogenic signaling is examined by the molecular mechanism based on the receptors, signaling pathways, crosstalk/bypassing and autocrine/paracrine/homeostatic networks involved in the signaling. Third, evaluation of estrogen action is discussed by focusing on the technologies and protocols of the assays for assessing estrogenicity. Understanding the molecular mechanisms of estrogen action is important to assess the action of endocrine disruptors and will be used for risk management based on pathway-based toxicity testing.

Ginsenoside Rb1 Treatment Attenuates Pulmonary Inflammatory Cytokine Release and Tissue Injury following Intestinal Ischemia Reperfusion Injury in Mice

Objective. Intestinal ischemia reperfusion (II/R) injury plays a critical role in remote organ dysfunction, such as lung injury, which is associated with nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway. In the present study, we tested whether ginsenoside Rb1 attenuated II/R induced lung injury by Nrf2/HO-1 pathway. Methods. II/R injury was induced in male C57BL/6J mice by 45 min of superior mesenteric artery (SMA) occlusion followed by 2 hours of reperfusion. Ginsenoside Rb1 was administrated prior to reperfusion with or without ATRA (all-transretinoic acid, the inhibitor of Nrf2/ARE signaling pathway) administration before II/R. Results. II/R induced lung histological injury, which is accompanied with increased levels of malondialdehyde (MDA), interleukin- (IL-) 6, and tumor necrosis factor- (TNF-) α but decreased levels of superoxide dismutase (SOD) and IL-10 in the lung tissues. Ginsenoside Rb1 reduced lung histological injury and the levels of TNF-α and MDA, as well as wet/dry weight ratio. Interestingly, the increased Nrf2 and HO-1 expression induced by II/R in the lung tissues was promoted by ginsenoside Rb1 treatment. All these changes could be inhibited or prevented by ATRA. Conclusion. Ginsenoside Rb1 is capable of ameliorating II/R induced lung injuries by activating Nrf2/HO-1 pathway.

Neurotoxin mechanisms and processes relevant to Parkinson's disease: an update

The molecular mechanism responsible for degenerative process in the nigrostriatal dopaminergic system in Parkinson's disease (PD) remains unknown. One major advance in this field has been the discovery of several genes associated to familial PD, including alpha synuclein, parkin, LRRK2, etc., thereby providing important insight toward basic research approaches. There is an consensus in neurodegenerative research that mitochon dria dysfunction, protein degradation dysfunction, aggregation of alpha synuclein to neurotoxic oligomers, oxidative and endoplasmic reticulum stress, and neuroinflammation are involved in degeneration of the neuromelanin-containing dopaminergic neurons that are lost in the disease. An update of the mechanisms relating to neurotoxins that are used to produce preclinical models of Parkinson´s disease is presented. 6-Hydroxydopamine, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, and rotenone have been the most wisely used neurotoxins to delve into mechanisms involved in the loss of dopaminergic neurons containing neuromelanin. Neurotoxins generated from dopamine oxidation during neuromelanin formation are likewise reviewed, as this pathway replicates neurotoxin-induced cellular oxidative stress, inactivation of key proteins related to mitochondria and protein degradation dysfunction, and formation of neurotoxic aggregates of alpha synuclein. This survey of neurotoxin modeling-highlighting newer technologies and implicating a variety of processes and pathways related to mechanisms attending PD-is focused on research studies from 2012 to 2014.

Efficacy and Safety of Panax notoginseng Saponin Therapy for Acute Intracerebral Hemorrhage, Meta-Analysis, and Mini Review of Potential Mechanisms of Action

Intracranial/intracerebral hemorrhage (ICH) is a leading cause of death and disability in people with traumatic brain injury (TBI) and stroke. No proven drug is available for ICH. Panax notoginseng (total saponin extraction, PNS) is one of the most valuable herb medicines for stroke and cerebralvascular disorders in China. We searched for randomized controlled clinical trials (RCTs) involving PNS injection to treat cerebral hemorrhage for meta-analysis from various databases including the Chinese Stroke Trials Register, the trials register of the Cochrane Complementary Medicine Field, the Cochrane Central Register of Controlled Trials, MEDLINE, Chinese BioMedical disk, and China Doctorate/Master Dissertations Databases. The quality of the eligible trials was assessed by Jadad’s scale. Twenty (20) of the 24 identified randomized controlled trials matched the inclusive criteria including 984 ICH patients with PNS injection and 907 ICH patients with current treatment (CT). Compared to the CT groups, PNS-treated patients showed better outcomes in the effectiveness rate (ER), neurological deficit score, intracranial hematoma volume, intracerebral edema volume, Barthel index, the number of patients died, and incidence of adverse events. Conclusion: PNS injection is superior to CT for acute ICH. A review of the literature shows that PNS may exert multiple protective mechanisms against ICH-induced brain damage including hemostasis, anti-coagulation, anti-thromboembolism, cerebral vasodilation, invigorated blood dynamics, anti-inflammation, antioxidation, and anti-hyperglycemic effects. Since vitamin C and other brain cell activators (BCA) that are not considered common practice were also used as parts of the CT in several trials, potential PNS and BCA interactions could exist that may have made the effect of PNS therapy less or more impressive than by PNS therapy alone. Future PNS trials with and without the inclusion of such controversial BCAs as part of the CT could clarify the situation. As PNS has a long clinical track record in Asia, it could potentially become a therapy option to treat ICH in the US and Europe. Further clinical trials with better experimental design could determine the long-term effects of PNS treatment for TBI and stroke.

Induction of GADD45α protects M17 neuroblastoma cells against MPP*

Growth arrest and DNA-damage-inducible protein 45α (GADD45α) is an important member of the family of growth arrest and DNA damage-inducible (GADD) proteins. The expression patterns and possible roles of GADD45α in Parkinson's disease (PD) are so far less understood. In this study, we found that 1-methyl-4-phenylpyridinium (MPP+) treatment up-regulates the expression of GADD45α in both a time-dependent manner and a dose-dependent manner in human dopamine neuroblastoma M17 cells. The up-regulation of GADD45α was abolished by pretreatment with the c-Jun N-terminal kinases (JNK) inhibitor SP600125 but not the p38 specific inhibitor SB203580. Further study revealed that c-Jun silencing abolished the effects of MPP+ on the expression of GADD45α. Important, ChIP studies verified the ability of c-Jun to bind to the GADD45 promoter. In addition, we found that inhibition of GADD45α by small RNA interference exacerbates the impaired cell viability, LDH release, and apoptosis induced by MPP+. Correspondingly, silence of GADD45 exacerbated Caspase-3 activation induced by MPP+. These data suggested a neuroprotective effect of GADD45α against MPP+ neurotoxicity.