A study of ginsenoside-Rd in a renal ischemia-reperfusion model

Ginsenoside Rd Promotes Cardiac Repair After Myocardial Infarction by Modulating Monocytes/Macrophages Subsets Conversion

Purpose

This study aimed to elucidate the potential molecular mechanisms by which GSRd improves cardiac inflammation and immune environment after MI.

Materials and Methods

The potential target genes of GSRd were predicted using the STITCH database. In vivo, MI mice models were established by left anterior descending ligation and were divided into the sham group, MI + Vehicle group, and MI + GSRd group. DMSO, DMSO, and GSRd 50 μL/day were intraperitoneally injected, respectively. After 28 days, echocardiography, Masson staining, immunofluorescence staining, flow cytometry, RT-PCR, and Western blot were performed. Mice peritoneal macrophages were extracted in vitro, and Western blot was performed after GSRd and/or Akt inhibitor MK2206 intervention.

Results

GSRd significantly improved mouse myocardial function, attenuated cardiac fibrosis, and inhibited inflammation and apoptosis in myocardial tissues after myocardial infarction. Meanwhile, GSRd increased non-classical Ly6C^low Mos/Mps while reduced of classical Ly6C^high Mos/Mps at the same time in myocardial tissues. In addition, GSRd significantly reversed the activity of p-Akt and p-mTOR in the heart Mos/Mps after MI. In vitro studies showed that the activity of p-Akt and p-mTOR in peritoneal macrophages were significantly increased in a dose-dependent manner after GSRd treatment. Furthermore, the AKT inhibitor MK2206 was found to block the enhanced activity of p-Akt and p-mTOR induced by GSRd in peritoneal macrophages.

Conclusion

GSRd can enhance the transformation of Ly6C^high Mos/Mps to Ly6C^low Mos/Mps in mice after MI by activating the Akt/mTOR signaling pathway, inhibiting cardiac dysfunction and promoting cardiac repair.

Biotransformation, Pharmacokinetics, and Pharmacological Activities of Ginsenoside Rd Against Multiple Diseases

Panax ginseng C.A. Mey. has a history of more than 4000 years and is widely used in Asian countries. Modern pharmacological studies have proved that ginsenosides and their compounds have a variety of significant biological activities on specific diseases, including neurodegenerative diseases, certain types of cancer, gastrointestinal disease, and metabolic diseases, in which most of the interest has focused on ginsenoside Rd. The evidentiary basis showed that ginsenoside Rd ameliorates ischemic stroke, nerve injury, cancer, and other diseases involved in apoptosis, inflammation, oxidative stress, mitochondrial damage, and autophagy. In this review, we summarized available reports on the molecular biological mechanisms of ginsenoside Rd in neurological diseases, cancer, metabolic diseases, and other diseases. We also discussed the main biotransformation pathways of ginsenoside Rd obtained by fermentation.

Panax Ginseng C.A.Mey. as Medicine: The Potential Use of Panax Ginseng C.A.Mey. as a Remedy for Kidney Protection from a Pharmacological Perspective

Panax ginseng C.A.Mey. has been widely consumed as food/diet supplements from natural sources, and its therapeutic properties have also aroused widespread concern. Therapeutic properties of Panax ginseng C.A.Mey. such as anti-inflammatory, ameliorating chronic inflammation, enhancing the immunity, resisting the oxidation again, and regulating the glucose and lipid metabolism have been widely reported. Recent years, lots of interesting studies have reported the potential use of Panax ginseng C.A.Mey. in the management of DKD. DKD has become the leading cause of end-stage renal disease worldwide, which increases the risk of premature death and poses a serious financial burden. Although DKD is somehow controllable with different drugs such as Angiotensin-Converting Enzyme Inhibitors (ACEI), Angiotensin Receptor Blockers (ARB) and lowering-glucose agents, modern dietary changes associated with DKD have facilitated research to assess the preventive and therapeutic merits of diet supplements from natural sources as medicine including Panax ginseng C.A.Mey. Findings from many scientific evidences have suggested that Panax ginseng C.A.Mey. can relieve the pathological status in cellular and animal models of DKD. Moreover, a few studies showed that alleviation of clinical phenotype such as reducing albuminuria, serum creatinine and renal anemia in DKD patients after application or consumption of Panax ginseng C.A.Mey.. Therefore, this review aims to discuss the effectiveness of Panax ginseng C.A.Mey. as medicine for targeting pathological phenotypes in DKD from a pharmacological perspective. This review will provide new insights into the potential understanding use of Panax ginseng C.A.Mey. in the management of DKD in clinical settings.

Pectin-Lyase-Modified Ginseng Extract and Ginsenoside Rd Inhibits High Glucose-Induced ROS Production in Mesangial Cells and Prevents Renal Dysfunction in db/db Mice

Diabetes increases the incidence rate of chronic renal disease. Pectin-lyase-modified ginseng (GS-E3D), with enhanced ginsenoside Rd content, has been newly developed. In this study, renal protective roles of GS-E3D in type-2 diabetic db/db mice were investigated. The generation of reactive oxygen species (ROS) induced by high glucose (25 mM) was reduced by ES-E3D (75%) and ginsenoside Rd (60%). Diabetic db/db mice received 100 or 250 mg/kg/day of GS-E3D daily via oral gavage for 6 weeks. Albuminuria and urinary 8-hydroxy-2'-deoxyguanosine (8-OhdG, an oxidative stress marker) levels were increased in db/db mice and the levels recovered after GS-E3D treatment. In renal tissues, TUNEL-positive cells were decreased after GS-E3D treatment, and the increased apoptosis-related protein expressions were restored after GS-E3D treatment. Therefore, GS-E3D has a potent protective role in diabetes-induced renal dysfunction through antioxidative and antiapoptotic activities. These results may help patients to select a dietary supplement for diabetes when experiencing renal dysfunction.

The antioxidant activities of Korean Red Ginseng (Panax ginseng) and ginsenosides: A systemic review through in vivo and clinical trials

A wide range of studies have steadily pointed out the relation of oxidative stress to the primary and secondary causes of human disease and aging. As such, there have been multiple misconceptions about oxidative stress. Most of reactive oxygen species (ROS) generated from chronic diseases cause oxidative damage to cell membrane lipids and proteins. ROS production is increased by abnormal stimulation inside and outside in the body, and even though ROS are generated in cells in response to abnormal metabolic processes such as disease, it does not mean that they directly contribute to the pathogenesis of a disease. Therefore, the focus of treatment should not be on ROS production itself but on the prevention and treatment of diseases linked to ROS production, including types 1 and 2 diabetes, cancer, heart disease, schizophrenia, Parkinson's disease, and Alzheimer's disease. In this regard, Korean Red Ginseng (KRG) has been traditionally utilized to help prevent and treat diseases such as diabetes, cancer, inflammation, nervous system diseases, cardiovascular disease, and hyperlipidemia. Therefore, this review was intended to summarize in vivo animal and human clinical studies on the antioxidant activities of KRG and its components, ginsenosides.

Hormesis and Ginseng: Ginseng Mixtures and Individual Constituents Commonly Display Hormesis Dose Responses, Especially for Neuroprotective Effects

This paper demonstrates that ginseng mixtures and individual ginseng chemical constituents commonly induce hormetic dose responses in numerous biological models for endpoints of biomedical and clinical relevance, typically providing a mechanistic framework. The principal focus of ginseng hormesis-related research has been directed toward enhancing neuroprotection against conditions such as Alzheimer's and Parkinson's Diseases, stroke damage, as well as enhancing spinal cord and peripheral neuronal damage repair and reducing pain. Ginseng was also shown to reduce symptoms of diabetes, prevent cardiovascular system damage, protect the kidney from toxicities due to immune suppressant drugs, and prevent corneal damage, amongst other examples. These findings complement similar hormetic-based chemoprotective reports for other widely used dietary-type supplements such as curcumin, ginkgo biloba, and green tea. These findings, which provide further support for the generality of the hormetic dose response in the biomedical literature, have potentially important public health and clinical implications.

Non-clinical pharmacokinetic behavior of ginsenosides

Ginsenosides, the major active ingredients of ginseng and other plants of the genus Panax, have been used as natural medicines in the East for a long time; in addition, their popularity in the West has increased owing to their various beneficial pharmacological effects. There is therefore a wealth of literature regarding the pharmacological effects of ginsenosides. In contrast, there are few comprehensive studies that investigate their pharmacokinetic behaviors. This is because ginseng contains the complicated mixture of herbal materials as well as thousands of constituents with complex chemical properties, and ginsenosides undergo multiple biotransformation processes after administration. This is a significant issue as pharmacokinetic studies provide crucial data regarding the efficacy and safety of compounds. Moreover, there have been many difficulties in the development of the optimal dosage regimens of ginsenosides and the evaluation of their interactions with other drugs. Therefore, this review details the pharmacokinetic properties and profiles of ginsenosides determined in various animal models administered through different routes of administration. Such information is valuable for designing specialized delivery systems and determining optimal dosing strategies for ginsenosides.

Application of Herbal Traditional Chinese Medicine in the Treatment of Acute Kidney Injury

Acute kidney injury (AKI) is a clinical syndrome characterized by a rapid loss of renal function, which may further develop into chronic kidney damage (CKD) or even end-stage renal disease (ESRD). AKI is a global health problem associated with high morbidity and costly treatments, and there is no specific or effective strategy to treat AKI. In recent years, Traditional Chinese Medicine (TCM) has attracted more attention, with lines of evidence showing that application of TCM improved AKI, and the mechanisms of action for some TCMs have been well illustrated. However, reviews summarizing the progress in this field are still lacking. In this paper, we reviewed TCM preparations and TCM monomers in the treatment of AKI over the last 10 years, describing their renal protective effects and mechanisms of action, including alleviating inflammation, programmed cell death, necrosis, and reactive oxygen species. By focusing on the mechanisms of TCMs to improve renal function, we provide effective complementary evidence to promote the development of TCMs to treat AKI. Moreover, we also summarized TCMs with nephrotoxicity, which provides a more comprehensive understanding of TCMs in the treatment of AKI. This review may provide a theoretical basis for the clinical application of TCMs in the future.

GS-E3D, a new pectin lyase-modified red ginseng extract, inhibited diabetes-related renal dysfunction in streptozotocin-induced diabetic rats

Background

GS-E3D is a newly developed pectin lyase-modified red ginseng extract. The purpose of this study was to investigate the therapeutic effects of GS-E3D on diabetes-related renal dysfunction in streptozotocin-induced diabetic rats.

Method

GS-E3D (25, 50, and 100 mg/kg body weight per day) was administered for 6 weeks. The levels of blood glucose and hemoglobin A1c, and of urinary albumin, 8-hydroxy-2′-deoxyguanosine (8-OHdG), and advanced glycation end-products (AGEs) were determined. Kidney histopathology, renal accumulation of AGEs, and expression of α-smooth muscle actin (α-SMA) were also examined.

Results

Administration of GS-E3D for 6 weeks reduced urinary levels of albumin, 8-OHdG, and AGEs in diabetic rats. Mesangial expansion, renal accumulation of AGEs, and enhanced α-SMA expression were significantly inhibited by GS-E3D treatment. Oral administration of GS-E3D dose-dependently improved all symptoms of diabetic nephropathy by inhibiting renal accumulation of AGEs and oxidative stress.

Conclusion

The results of this study indicate that the use of GS-E3D as a food supplement may provide effective treatment of diabetes-induced renal dysfunction.

Effect of Whole-Body Cryotherapy on Antioxidant Systems in Experimental Rat Model

Background

The purpose of this study was to verify the effect of whole-body cryotherapy (WBC) in rats on their antioxidant systems, lipid peroxidation products, and their total oxidative status at different exposure times and temperatures.

Methods

Antioxidants in serum, plasma, liver, and erythrocytes were evaluated in two study groups following 1 min of exposure to −60°C and −90°C, for 5 and 10 consecutive days.

Results

WBC increased the activity of superoxide dismutase, catalase in the group subjected to 5 and 10 days exposure, −60°C. The glutathione S-transferase activity increased in the groups subjected to 10 days WBC sessions. Total antioxidant capacity increased after 5 and 10 days of 1 min WBC, −60°C; a decrease was observed at −90°C. A decreased level of erythrocyte malondialdehyde concentration was observed at −60°C after 5 and 10 days of cryostimulation. An increased concentration was measured at −90°C after 10 days, and increase of erythrocyte malondialdehyde concentration after 5 days, −90°C.

Conclusions

To the best of our knowledge, this is the first research showing the effect of WBC in rats at different exposure times and temperatures. The effect of cryotherapy on enzymatic and nonenzymatic antioxidant systems was observed in the serum of animals exposed to a temperature of −60°C in comparison to control.

The effect of Chinese herbal medicine on hemorrhagic shock: A systematic review and meta-analysis

BACKGROUND

Chinese herbal medicine (CHM) has been widely used in the treatment of hemorrhagic shock (HS) in China. Many controlled trials have been undertaken to investigate its efficacy.

OBJECTIVE

To evaluate the effectiveness and safety of CHM for Hemorrhagic Shock patients.

METHODS

We screening the Web of ScienceDirect database, PubMed, the Cochrane Library, EMBASE, China Biomedical Database web (CBM), China National Knowledge Infrastructure (CNKI) and WanFang database (WF), from inception to January 2015. All the randomized controlled trials (RCTs) that compared CHM plus conventional therapy with conventional therapy alone for HS patients were included. Meta-analysis on included studies was performed using fixed-effects model with RevMan 5.2. Risk ratio (RR) or mean difference (MD) with a 95% confidence interval (CI) was used as effect measure. STATA 12.0 was used for publication bias.

RESULTS

Fifteen RCTs involving 1076 participants were included in the meta-analysis. CHM combined with conventional therapy was tested to be more effective in reduce mortality (RR=0.24, 95%CI:0.13-0.46, P<0.0001), reduce the incidence of MODS (RR=0.47, 95%CI: 0.34-0.66,P<0.00001), symptomatic improvement: increase blood pressure (BP) (MD=8.83, 95%CI:6.82-10.84,P<0.00001), regulate heart rate (MD=-7.6,95%CI:-9.17 to -6.02,P<0.00001), increase urine volume (MD=7.26, 95%CI:5.00-9.53, P<0.00001), compared with conventional therapy alone. No serious adverse events were reported.

CONCLUSIONS

CHM combined with conventional therapy seems to be more effective on HS patients. However, the analysis results should be interpreted with caution due to the low methodological quality of the included trials. Future, the rigorously designed, high methodological quality, multicenter and large-scale trials are needed to confirm these conclusions.

Protective effects of ginseng extracts and common anti-aggregant drugs on ischaemia-reperfusion injury

OBJECTIVE

Ginseng is a traditional herbal medicinal product widely used for various types of diseases because of its cellular protective effects. Possible protective effects of ginseng were investigated in blood, cardiac and renal tissue samples and compared with common anti-aggregant agents in an animal ischaemia-reperfusion (I/R) model.

METHODS

Twenty rats were equally divided into four different groups as follows: control group (I/R-induced group without drug use), group I (acetylsalicylic acid-administered group), group II (clopidogrel bisulfate-administered group), group III (ginsenoside Rb1-administered group). For the groups assigned to a medication, peripheral I/R was induced by clamping the femoral artery one week after initiation of the specified medication. After reperfusion was initiated, cardiac and renal tissues and blood samples were obtained from each rat with subsequent analysis of nitrogen oxide (NOx), malondialdehyde (MDA), paraoxonase 1 (PON1) and prolidase.

RESULTS

NOx levels were similar in each group. Significant decrements were observed in serum PON1 levels in each group when compared with the control (p < 0.05). Serum MDA levels were significantly lower in groups II and III (p < 0.05). Ameliorated renal prolidase levels were detected in study groups (p < 0.05) and recovered cardiac prolidase levels were obtained in groups II and III (p < 0.05).

CONCLUSION

These findings indicate that ginseng extracts may have a potential beneficial effect in I/R injury. However, more comprehensive studies are required to clarify the hypothetical cardiac, renal and systemic protective effects in reperfusion-induced oxidative damage.

Antioxidant effects of cultured wild ginseng root extracts on the male reproductive function of boars and guinea pigs

The main objective of this study was to investigate the effects of cultured wild ginseng root extracts (cWGRE) on the sperm of boars and the reproductive system of guinea pigs. Firstly, semen collected from boars (n=10) were incubated in 38°C for 1h with xanthine and xanthine oxidase to generate ROS. The cWGRE was added to the sperm culture system to test its antioxidant effect on the boar sperm. The amount of Reactive Oxygen Species (ROS) was measured by a chemiluminescence assay using luminol. The results indicated that the addition of cWGRE to boar sperm culture inhibited xanthine and xanthine oxidase-induced ROS concentrations. Treatment with cWGRE also had a positive effect on maintaining sperm motility. Effects of cWGRE administration on vitamin C-deficient guinea pigs were further investigated. Hartley guinea pigs (n=25) at 8 weeks of age were randomly divided into five groups. With the exception of the positive control group, each group was fed vitamin C-deficient feed for 21days (d). Respective groups were also orally administered cWGRE, ginseng extract, or mixed ginsenosides for 21 days. In comparison to the control group, oral administration of cWGRE reduced (P<0.05) amount of lipid peroxidation and increased (P<0.05) both glutathione peroxidase concentrations and the trolox equivalent antioxidant capacity. In addition, administration of cWGRE induced increases (P<0.05) in body weight, testosterone concentrations, and spermatid populations. The results of the present study support our hypothesis that cWGRE has positive effects on male reproductive functions via suppression of ROS production.

Ginsenoside Rd attenuates Aβ25-35-induced oxidative stress and apoptosis in primary cultured hippocampal neurons

One of the most common pathological changes in Alzheimer's disease (AD) brain is the large number of amyloid β (Aβ) peptides accumulating in lesion areas. Ginsenosides are the most active components extracted from ginseng. Ginsenoside Rd (GRd) is a newly discovered saponin that has a stronger pharmacological activity than other ginsenosides, especially in neuroprotection. Here we examined the neuroprotective effects of GRd against neuronal insults induced by Aβ25-35 in primary cultured hippocampal neurons. A 10μM GRd treatment significantly prevented the loss of hippocampal neurons induced by Aβ25-35. In addition, GRd significantly ameliorated Aβ25-35-induced oxidative stress by decreasing the reactive oxygen species (ROS) production and malondialdehyde (MDA) level, and increasing the levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px); which is similar in treatments with 10μM of probucol (PB) and 100μM of edaravone (EDA). Moreover, our present study demonstrated that GRd significantly enhanced the expression of Bcl-2 mRNA, and decreased the expressions of Bax mRNA and Cyt c mRNA. GRd also downregulated the protein level of cleaved Caspase-3 compared to controls. These results highlighted the neuroprotective effects of GRd against Aβ25-35-induced oxidative stress and neuronal apoptosis, suggesting that this may be a promising therapeutics against AD.

Heat-processed Panax ginseng and diabetic renal damage: active components and action mechanism

Diabetic nephropathy is one of the serious complications in patients with either type 1 or 2 diabetes mellitus but current treatments remain unsatisfactory. Results of clinical research studies demonstrate that Panax ginseng can help adjust blood pressure and reduce blood sugar and may be advantageous in the treatment of tuberculosis and kidney damage in people with diabetes. The heat-processing method to strengthen the efficacy of P. ginseng has been well-defined based on a long history of ethnopharmacological evidence. The protective effects of P. ginseng on pathological conditions and renal damage associated with diabetic nephropathy in the animal models were markedly improved by heat-processing. The concentrations of less-polar ginsenosides (20(S)-Rg3, 20(R)-Rg3, Rg5, and Rk1) and maltol in P. ginseng were significantly increased in a heat-processing temperature-dependent manner. Based on researches in animal models of diabetes, ginsenoside 20(S)-Rg3 and maltol were evaluated to have therapeutic potential against diabetic renal damage. These effects were achieved through the inhibition of inflammatory pathway activated by oxidative stress and advanced glycation endproducts. These findings indicate that ginsenoside 20(S)-Rg3 and maltol are important bioactive constituents of heat-processed ginseng in the control of pathological conditions associated with diabetic nephropathy.

Ginsenoside Rd for acute ischemic stroke: translating from bench to bedside

Numerous studies have identified pathophysiological mechanisms of acute ischemic stroke and have provided proof-of-principle evidence that strategies designed to impede the ischemic cascade, namely neuroprotection, can protect the ischemic brain. However, the translation of these therapeutic agents to the clinic has not been successful. Ginsenoside Rd, a dammarane-type steroid glycoside extracted from ginseng plants, has exhibited an encouraging neuroprotective efficacy in both laboratory and clinical studies. This article attempts to provide a synopsis of the physiochemical profile, pharmacokinetics, pharmacodynamics, clinical efficacy, safety and putative therapeutic mechanisms of Rd. Finally, the authors discuss the validity of Rd as a neuroprotective agent for acute ischemic stroke.

Effects of Natural Bioactive Products on the Growth and Ginsenoside Contents of Panax ginseng Cultured in an Aeroponic System

This study was conducted to evaluate the effects of natural bioactive products such as Manda enzyme (T1), Yangmyeongwon (T2), effective microorganisms (T3), and Kelpak (T4) on the growth and ginsenoside contents of Panax ginseng cultured in an aeroponic system using a two-layer vertical type of nutrient bath under natural light conditions. The growth of ginseng plants showed specific characteristics according to the positions in which they were cultured due to the difference of light transmittance and temperature in the upper and lower layers during aeroponic culture in a two-layer vertical type of system. The growth of the aerial part of the leaves and stems of ginseng plants cultured in the lower layer (4,000 to 6,000 lx, 23℃ to 26℃) of the nutrient bath was observed to be superior to that of the ginseng plants cultured in the upper layer (12,000 to 15,000 lx, 25℃ to 28℃). The leaf area was significantly larger in the treatment of T2 and T4 (46.70 cm²) than with other treatments. Conversely, the values of the root weight and root diameter were higher in ginseng plants cultured in the upper layer of the nutrient bath. The root weight was significantly heavier in the treatment of T4 (6.46 g) and T3 (6.26 g) than with other treatments. The total ginsenoside content in the leaves and roots was highest in the ginseng plants cultured by the treatment of T1, at 16.20%, while the total ginsenoside content obtained by other treatments decreased in the order of T4, T5 (control), T2, and T3, at 13.21%, 12.30%, 14.84%, and 14.86%, respectively. The total ginsenoside content of the ginseng leaves was found to be significantly higher in the treatment of T1 in the lower layer of the nutrient bath, at 15.30%, while the content of the ginseng roots in the treatments of T3 and T4, at 1.27% and 1.23%, respectively, was significantly higher than in other treatments in the upper layer of the nutrient bath.

Ginsennoside rd attenuates cognitive dysfunction in a rat model of Alzheimer's disease

Alzheimer's disease is a neurodegenerative disease characterized by the production of β-amyloid proteins and hyperphosphorylation of tau protein. Inflammation and apoptotic severity were highly correlated with earlier age at onset of Alzheimer's disease and were also associated with cognitive decline. This study aims to examine whether the traditional Chinese medicine ginsennoside Rd could prevent cognitive deficit and take neuroprotective effects in β-amyloid peptide 1-40-induced rat model of Alzheimer's disease. To produce Alzheimer's disease animal model, aggregated β-amyloid peptide 1-40 injected into hippocampus bilaterally. Ginsennoside Rd protected their cognitive impairment and improved their memory function by daily intraperitoneal injection for 30 days consecutively. In addition, ginsennoside Rd alleviated the inflammation induced by β-amyloid peptide 1-40. Furthermore, ginsennoside Rd played a role in the down-regulation of caspase-3 proteins and reduced the apoptosis that normally followed β-amyloid peptide 1-40 injection. The results of this study showed that the pretreatment of ginsennoside Rd had neuroprotective effects in β-amyloid peptide 1-40-induced AD model rat.

Ginsenoside-Rd attenuates TRPM7 and ASIC1a but promotes ASIC2a expression in rats after focal cerebral ischemia

Our previous studies have showed that ginsenoside (GS)-Rd, a mono-compound isolated from traditional Chinese herb panax ginseng, has the neuroprotective effects following ischemic stroke. However, the underlying mechanisms are still largely unknown. Our latest study showed that GS-Rd could block calcium influx in cultured cortical neurons after excitotoxic injury, indicating that GS-Rd may act on cation channels. To explore this possibility, in this study, we used a rat middle cerebral artery occlusion (MCAO) model to examine the effects of GS-Rd on the expression of non-selective cation channels, including transient receptor potential melastatin (TRPM) and acid sensing ion channels (ASIC), and cation channels, including N-methyl-D-aspartate (NMDA) receptors, which all play essential roles in ischemic stroke. Our results showed that both TRPM and ASIC channels were expressed in the brain. At 24 h following MCAO insult, mRNA and protein expression levels of TRPM7, ASIC1a and ASIC2a were significantly increased. Pretreatment of 10 mg/kg GS-Rd attenuated MCAO-induced expression of TRPM7 and ASIC1a but promoted that of ASIC2a. In contrast, GS-Rd had no significant effects on the expression of NMDA receptors. Thus, our results suggest that GS-Rd neuroprotection following cerebral ischemia may be at least due to its effects on the expression of TRPM7, ASIC1a and ASIC2a.

Protective effects of ginsenoside Rd against okadaic acid-induced neurotoxicity in vivo and in vitro

ETHNOPHARMACOLOGICAL RELEVANCE

Panax ginseng, a traditional Chinese herbal medicine, has been widely used to restore the disease and enhance the healthy body in Asia for about 5000 years. The present study aimed to investigate the possible neuroprotective effects of ginsenoside Rd against OA-induced toxicity.

MATERIALS AND METHODS

Ginsenoside Rd was used in tauopahy models of Alzheimer's disease (AD). To mimic the in vivo or in vitro tau hyperphosphorylation, okadaic acid (OA), a protein phosphatase inhibitor, was bilaterally micro-infused into the cerebral ventricle of adult male Sprague-Dawley (SD) rats, or added in media of cultured cortical neurons. The phosphorylation levels of tau and the activities of protein phosphatase 2A (PP-2A) were measured and compared with ginsenoside Rd pretreated groups.

RESULTS

Pretreatment with ginsenoside Rd in SD rats (10mg/kg for 7 days) or in cultured cortical neurons (2.5 or 5μmol/L for 12h) reduced OA-induced neurotoxicity and tau hyperphosphorylation by enhancing the activities of PP-2A.

CONCLUSIONS

The result of the present work implied that ginsenoside Rd protected SD rats and cultured cortical neurons against OA-induced toxicity. The possible neuroprotective mechanism may be that ginsenoside Rd decreases OA-induced the hyperphosphorylation of tau by the increase in activities of PP-2A. Thus, this study promises that ginsenoside Rd might be a potential preventive drug candidate for AD and other tau pathology-related neuronal degenerative diseases.

Ginsenoside Rd attenuates early oxidative damage and sequential inflammatory response after transient focal ischemia in rats

We previously found that ginsenoside Rd (Rd), one of the main active ingredients in Panax ginseng, attenuates neuronal oxidative damage in vitro induced by hydrogen peroxide and oxygen-glucose deprivation. In this study, we sought to investigate the potential protective effects and associated mechanisms of Rd in a rat model of focal cerebral ischemia. Rats administered with Rd (0.1-200mg/kg) or vehicle was subjected to transient middle cerebral artery occlusion. Rd at the dose of 10-50mg/kg significantly reduced the infarct volume and improved the long-term neurological outcome up to 6 weeks after ischemia. To evaluate the underlying mechanisms, in vivo free radical generation was monitored using microdialysis, oxidative DNA damage was identified by 8-hydroxy-deoxyguanosine immunostaining, oxidative protein damage was identified by the assessment of protein carbonyl and advanced glycosylation end products, and lipid peroxidation was estimated by determining the malondialdehyde and 4-hydroxynonenal formations. Microdialysis results displayed a prominent inhibitory effect of Rd on the hydroxy radical formation trapped as 2,3- and 2,5-DHBA. Early accumulations of DNA, protein and lipid peroxidation products were also suppressed by Rd treatment. Although Rd partly preserved endogenous antioxidant activities in the ischemic penumbra, in sham rats without stroke, endogenous antioxidant activities were not affected by Rd. Furthermore, we assayed sequential inflammatory response in a later phase after ischemia. Rd significantly eliminated inflammatory injury as indicated by the suppression of microglial activation, inducible nitric oxide synthase and cyclooxygenase-2 expression. Collectively, these findings demonstrated that Rd exerts neuroprotection in transient focal ischemia, which may involve early free radicals scavenging pathway and a late anti-inflammatory effect.

Effects of the Chinese prescription Kangen-karyu and its crude drug Tanjin on ageing process in rats

The effects of the Chinese prescription Kangen-karyu and its crude drug Tanjin on the ageing process were investigated in rats. Diets supplemented with Kangen-karyu and Tanjin extracts decreased glycosylated protein levels in serum, a risk marker of ageing and ageing-related diseases. In addition, they inhibited the levels of thiobarbituric acid reactive substance in the serum and liver; Kangen-karyu in particular led to a strong decrease in hepatic mitochondrial thiobarbituric acid reactive substance. The decline in the reduced glutathione/oxidized glutathione ratio in the liver observed with ageing was ameliorated by Kangen-karyu and Tanjin, while these groups attenuated the increase in glutathione peroxidase activity of hepatic tissue against ageing. This suggests that Kangen-karyu and Tanjin regulate the glutathione redox cycle that maintains the cellular redox condition against age-related oxidative stress. Moreover, the overexpression of cytoplasmic cytochrome c observed with ageing was attenuated by Kangen-karyu and Tanjin. This provides new evidence that Kangen-karyu and Tanjin inhibit leakage of superoxide in mitochondria and attenuate cellular oxidative damage. Furthermore, Kangen-karyu and Tanjin would maintain mitochondrial function with ageing through the regulation of related protein expression such as bax and bcl-2 proteins. In addition, Kangen-karyu reduced the expression of nuclear factor kappa B; Kangen-karyu and Tanjin did not affect the expression of inhibitor kappa B. The present study demonstrated that Kangenkaryu prevented oxidative damage and mitochondrial dysfunction with ageing. Furthermore, Kangen-karyu showed a stronger protective effect against ageing by oxidative stress than Tanjin, probably through synergistic and/or additive effects.

Ginsenoside-Rd attenuates oxidative damage related to aging in senescence-accelerated mice

Among the various theories of the aging process, the free radical theory, which proposes that deleterious actions of free radicals are responsible for the functional deterioration associated with aging, has received widespread attention. The theory suggests that enhancement of the antioxidative defence system to attenuate free-radical-induced damage will counteract the aging process. We used senescence-accelerated mice (SAM) to investigate the relationship between aging and the antioxidative defence system and evaluated the effects of ginsenoside-Rd, the saponin from ginseng, by measuring antioxidative defence system parameters, including the glutathione (GSH)/glutathione disulfide (GSSG) redox status, antioxidative enzyme activity and level of lipid peroxidation. SAM at 11 months of age (old SAM) showed a significantly lower hepatic GSH/GSSG ratio, due to decreased GSH and increased GSSG levels, than SAM at 5 weeks of age (young SAM). However, the administration of ginsenoside-Rd at a dose of 1 or 5 mg kg−1 daily for 30 days to 10-month-old SAM significantly increased GSH, but decreased GSSG, resulting in elevation of the GSH/GSSG ratio. In addition, ginsenoside-Rd increased the activity of glutathione peroxidase (GSH-Px) and glutathione reductase that were both significantly lower in old SAM than in young SAM. This suggests that ginsenoside-Rd could play a crucial role in enhancing the defence system through regulation of the GSH/GSSG redox status. Moreover, decreases in the superoxide dismutase (SOD) and catalase activity in old SAM compared with young SAM were also revealed, indicating that the aging process resulted in suppression of the antioxidative defence system. However, ginsenoside-Rd did not affect SOD and catalase activity. As catalase is localized in peroxisome granules and GSH-Px is present in the cytoplasm and mitochondrial matrix, the site of ginsenoside-Rd action may be the cytoplasm and mitochondrial matrix. Furthermore, the serum and liver malondialdehyde levels, indicators of lipid peroxidation, were elevated with aging, while ginsenoside-Rd inhibited lipid peroxidation. This study indicates that the aging process leads to suppression of the antioxidative defence system and accumulation of lipid peroxidation products, while ginsenoside-Rd attenuates the oxidative damage, which may be responsible for the intervention of GSH/GSSG redox status.

Neuroprotective effects of ginsenoside Rd against oxygen-glucose deprivation in cultured hippocampal neurons

We previously found that ginsenoside Rd (GSRd), one of the main active ingredients in Panax Ginseng, attenuates H(2)O(2)-induced oxidative injury in PC12 cells. Mounting evidence suggests that the oxidative stress is crucially involved in the pathophysiologic process of ischemia. In the present study, we examined the protective role of GSRd to attenuate ischemic neuronal injury in vitro. Cultured hippocampal neurons were exposed to oxygen-glucose deprivation (OGD) for 2h followed by a 24-h reoxygenation. GSRd exhibited remarkable neuroprotection when presented during OGD and reoxygenation, which may be ascribed to its antioxidative properties by reducing the intracellular reactive oxygen species and malondialdehyde production; increasing glutathione content; and enhancing the antioxidant enzymatic activities of catalase, superoxide dismutase and glutathione peroxidase. Additionally, GSRd could stabilize the mitochondrial membrane potential and attenuate apoptotic death of hippocampal neurons after OGD exposure. These findings suggested that GSRd may be a potential neuroprotective agent for cerebral ischemic injury and should encourage further in vivo studies on stroke to explore the potential neuroprotective efficacy of GSRd.

Effects of ginsenosides Re and Rg3 on intracellular redox state and cell proliferation in C6 glioma cells

Background

Cellular redox state is important to cell growth and death. The growth of tumor cells may be modulated by intracellular reduced glutathione/oxidized glutathione (GSH/GSSG). The present study aims to investigate the effects of ginsenosides Re and Rg3 on cellular redox state and cell proliferation in C6 glioma cells.

Methods

Cultured C6 glioma cells were exposed to various concentrations of either Rg3 or Re for 24 hours. Cell growth and death were measured by the BrdU incorporation assay and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay respectively. Cellular redox state was determined by free radical production using flow cytometry and GSH/GSSG using spectrofluorometry.

Results

At a sub-lethal concentration, Re suppressed cell proliferation with a significant decrease in BrdU incorporation. Re did not increase reactive oxygen species (ROS) production but increased GSH/GSSG via increased activity of gamma glutamylcystenyl synthase (γ-GCS). In contrast, Rg3 increased free radical production and reduced GSH/GSSG. The effects of Rg3 were probably due to increased activity of glutathione peroxidase (GPx).

Conclusion

Re and Rg3 alter cellular redox state of C6 glioma cells in opposite directions. Changes in cellular redox state induced by Re and Rg3 are correlated with the proliferation rates of C6 glioma cells.

Antioxidative effects related to the potential anti-aging properties of the Chinese prescription Kangen-karyu and Carthami Flos in senescence-accelerated mice

The popular oxidative stress theory predicts that enhancement of the antioxidative defense system to attenuate free radical-induced damage counteracts the aging process. We used senescence-accelerated mice (SAM) because SAM has been shown to suppress the antioxidative defense system and mitochondrial dysfunction induced by oxidative stress. We investigated the antioxidative effects of the Chinese prescription Kangen-karyu and its crude drug component Carthami Flos. The administration of Kangen-karyu extract at 100 mg/kg body weight per day for 10 weeks inhibited generation of nitric oxide, superoxide and the hydroxyl radical (*OH), while Carthami Flos extract showed only *OH-scavenging activity. Diet supplemented with Kangen-karyu and Carthami Flos extracts enhanced the activities of the antioxidative enzymes superoxide dismutase in hepatic tissue and glutathione peroxidase in renal tissue, and reduced the hepatic lipid peroxidation level which increased with aging, indicating the protective action against oxidative stress by enhancing the antioxidative status. Hepatic and renal dysfunction with aging was also ameliorated by the administration of Kangen-karyu and Carthami Flos supplements. Furthermore, the observed antioxidative properties of the Chinese prescription Kangen-karyu were more evident than those of Carthami Flos. These findings suggest that the protective activity of Kangen-karyu against the oxidative tissue damages during aging may be due partly to synergistic and/or additive effects of its crude preparation. The present study strongly indicates that Kangen-karyu counteract the oxidative stress and ameliorating tissue damage possibly associated with aging in SAM.

Ginsenosides protect apical transporters of cultured proximal tubule cells from dysfunctions induced by h(2)o(2)

Oxidative stress has been implicated as a primary cause of renal failure in certain renal diseases. Indeed, renal proximal tubule is a very sensitive site to oxidative stress and retains functionally fully characterized transporters. It has been reported that ginsenosides have a beneficial effect on diverse diseases including oxidative stress. However, the protective effect of ginsenosides on oxidative stress has not been elucidated in renal proximal tubule cells. Thus, we examined the effect of ginsenosides on oxidative stress-induced alteration of apical transporters and its related mechanism in renal proximal tubule cells. In the present study, hydrogen peroxide (H(2)O(2)) (>10(-5) M) inhibited alpha-methyl-D-glucopyranoside uptake in a dose-dependent manner (p < 0.05). It also inhibited Pi and Na(+) uptake. At a concentration of 20 microg/ml, total ginsenosides significantly reduced H(2)O(2)-induced inhibition of apical transporters. In contrast, protopanaxadiol (PD) and protopanaxatriol (PT) saponins exhibited a less preventive effect than total ginsenosides (p < 0.05). Furthermore, we examined its action mechanism. H(2)O(2) increased lipid peroxide formation, arachidonic acid (AA) release, and Ca(2+) uptake. These effects on H(2)O(2) were significantly prevented by total ginsenosides and PD or PT sanponins. However, total ginsenosides appear to be more protective than PD and PT saponins (p < 0.05). In conclusion, ginsenosides prevented H(2)O(2)-induced inhibition of apical transporters via a decrease in oxidative stress, AA release, and Ca(2+) uptake in primary cultured renal proximal tubule cells.

Buckwheat extract inhibits progression of renal failure

Rats subjected to partial resection of the parenchyma showed reduced radical-scavenging activity in the remaining kidney and increased severity of renal tissue lesions. However, in similarly nephrectomized rats given buckwheat extract, the state of oxidative stress improved by restoring the decreased activities of reactive oxygen species-scavenging enzymes such as superoxide dismutase and catalase. The degree of mesangial proliferation, severity of extratubular lesions such as crescents and adhesions, glomerulosclerosis index, and severity of tubular interstitial lesions also improved. In addition, nephrectomized rats given buckwheat extract showed improvement in renal function, as indicated by decreased serum level of creatinine, with a significant decrease in the level of methylguanidine, a uremic toxin produced from creatinine in the presence of hydroxyl radical.

Role of ginsenoside-Rd in cisplatin-induced renal injury: special reference to DNA fragmentation

DNA of LLC-PK(1) cells cultured with cisplatin was fragmented to produce low-molecular-weight structures. Agarose gel electrophoresis of the DNA revealed a ladder pattern characteristic of apoptosis, indicating the induction of apoptosis by cisplatin. However, the degree of apoptosis was lower in cells cultured with cisplatin in the presence of ginsenoside-Rd, and this was accompanied by suppressed leakage of lactic dehydrogenase into the culture medium. The ladder pattern was detected on electrophoresis of DNA in renal tissue samples obtained from rats given an intravenous injection of cisplatin. Such DNA fragmentation was less conspicuous in rats given ginsenoside-Rd orally for 30 days prior to cisplatin administration. Significant suppression of the DNA fragmentation was also demonstrated by densitometry, and measurement of urea nitrogen and creatinine in blood also showed a marked decrease in their respective levels in rats administered ginsenoside-Rd. The present findings suggest that ginsenoside-Rd ameliorates cisplatin-induced renal injury, a process in which apoptosis plays a central role, and thereby causes restoration of the renal function.

Do antioxidant strategies work against aging and age-associated disorders? Propargylamines: a possible antioxidant strategy

The free radical theory of aging was initially proposed by Harman half a century ago primarily to explain biological aging processes. Although administration of so-called antioxidant chemicals, which have been tested in the past for several decades, turned out to be mostly ineffective in prolonging the life spans of animals, the same theory of age-associated diseases appears to be increasingly supported in the last two decades. Despite these difficulties, the success in extending life span of 4 different animal species (mice, rats, hamsters, and dogs) with (-)deprenyl (including a study of our group) indicates that there might exist another type of antioxidant strategy in addition to a simple administration of antioxidant chemicals. (-)Deprenyl has also been shown to increase superoxide dismutase (SOD) and catalase (CAT) activities selectively in brain dopaminergic tissues. Interestingly, we have recently shown that another propargylamine, rasagiline not only increases antioxidant enzyme activities (CAT and SOD) in brain dopaminergic regions as (-)deprenyl does, but also increases CAT and SOD activities in extrabrain catecholaminergic systems such as the heart and kidneys as well. These recent observations coupled with previous observations on the life span of animals with (-)deprenyl suggest that pharmacological modulation of endogenous antioxidant enzyme activities could be one potential antioxidant strategy against aging and age-associated disorders. If the causal relationship between the two effects of (-)deprenyl exists as we hypothesized, we might be able to advance the elucidation of mechanism(s) of aging based on the free radical theory of aging.

Eleutherococcus senticosus (Rupr. & Maxim.) Maxim. (Araliaceae) as an adaptogen: a closer look

The adaptogen concept is examined from an historical, biological, chemical, pharmacological and medical perspective using a wide variety of primary and secondary literature. The definition of an adaptogen first proposed by Soviet scientists in the late 1950s, namely that an adaptogen is any substance that exerts effects on both sick and healthy individuals by 'correcting' any dysfunction(s) without producing unwanted side effects, was used as a point of departure. We attempted to identify critically what an adaptogen supposedly does and to determine whether the word embodies in and of itself any concept(s) acceptable to western conventional (allopathic) medicine. Special attention was paid to the reported pharmacological effects of the 'adaptogen-containing plant' Eleutherococcus senticosus (Rupr. & Maxim.) Maxim. (Araliaceae), referred to by some as 'Siberian ginseng', and to its secondary chemical composition. We conclude that so far as specific pharmacological activities are concerned there are a number of valid arguments for equating the action of so-called adaptogens with those of medicinal agents that have activities as anti-oxidants, and/or anti-cancerogenic, immunomodulatory and hypocholesteroletic as well as hypoglycemic and choleretic action. However, 'adaptogens' and 'anti-oxidants' etc. also show significant dissimilarities and these are discussed. Significantly, the classical definition of an adaptogen has much in common with views currently being invoked to describe and explain the 'placebo effect'. Nevertheless, the chemistry of the secondary compounds of Eleutherococcus isolated thus far and their pharmacological effects support our hypothesis that the reported beneficial effects of adaptogens derive from their capacity to exert protective and/or inhibitory action against free radicals. An inventory of the secondary substances contained in Eleutherococcus discloses a potential for a wide range of activities reported from work on cultured cell lines, small laboratory animals and human subjects. Much of the cited work (although not all) has been published in peer-reviewed journals. Six compounds show various levels of activity as anti-oxidants, four show anti-cancer action, three show hypocholesterolemic activity, two show immunostimulatory effects, one has choleretic activity and one has the ability to decrease/moderate insulin levels, one has activity as a radioprotectant, one shows anti-inflammatory and anti-pyretic activities and yet another has shown activity as an antibacterial agent. Some of the compounds show more than one pharmacological effect and some show similar effects although they belong to different chemical classes. Clearly, Eleutherococcus contains pharmacologically active compounds but one wishes that the term adaptogen could be dropped from the literature because it is vague and conveys no insights into the mechanism(s) of action. If a precise action can be attributed to it, then the exact term for said action should obviously be used; if not, we strongly urge that generalities be avoided. Also, comparison of Eleutherococcus with the more familiar Panax ginseng C.A. Meyer (Araliaceae), 'true ginseng' has underscored that they differ considerably chemically and pharmacologically and cannot be justifiably considered as mutually interchangeable. Accordingly, we recommend that the designation 'Siberian ginseng' be dropped and be replaced with 'Eleutherococcus'. In the case of both Eleutherococcus and true ginseng, problems inherent in herbal preparation use include inconsistencies not only in terms of indications for use, but in the nomenclature of constituent chemical compounds, standardization, dosage and product labeling. (ABSTRACT TRUNCATED)

The role of ginsenoside-Rd in cisplatin-induced acute renal failure

Ginsenoside-Rd has been proved to decrease the severity of renal injury induced by cisplatin, in which proximal urinaferous tubules represent the main site of injury. When ginsenoside-Rd was given orally at a dose of 1 or 5 mg/kg body weight/day for 30 consecutive days prior to cisplatin injection, the activities of the antioxidation enzymes superoxide dismutase and catalase were higher, while malondialdehyde levels in serum and renal tissue were lower in the treated rats than in the controls. The levels of urea nitrogen and creatinine in serum were decreased in rats given ginsenoside-Rd. Decreased urinary levels of glucose, sodium and potassium reflected a protective action against the renal dysfunction caused by cisplatin. In addition, it was demonstrated that ginsenoside-Rd affected cultured proximal tubule cells exposed to cisplatin.

Protopanaxatriol ginsenosides inhibit glucose uptake in primary cultured rabbit renal proximal tubular cells by arachidonic acid release

Ginsenosides are involved in protective action against renal dysfunction and the regulation of renal functions. However, the effects of ginsenosides on glucose reabsorption are not yet known in renal proximal tubular cells. The aim of this study was to examine the effects of ginsenosides, protopanaxadiol (PD) saponin and protopanaxatriol (PT) saponin, on alpha-methyl-D-glucopyranoside (alpha-MG) uptake and its mechanism of action in primary cultured rabbit renal proximal tubular cells (PTCs). The alpha-MG uptake was inhibited by 90% by 0.5mM phloridizin and by removal of Na+ in the PTCs. These are typical characteristics described for the proximal tubule. To determine the time- and dose-dependent effects of PD and PT saponins on alpha-MG uptake, PTCs were incubated with different concentrations of PD and PT saponins (10-100 microg/ml) and for different time periods (from 10 min to 24 h). PT saponin (>/=50 microg/ml) from 30 min inhibited alpha-MG uptake; however, PD saponin did not alter the alpha-MG uptake at any doses and time periods. In the kinetic analysis of alpha-MG uptake, PT saponin produced a significant decrease in Vmax. The PT saponin induced inhibition of alpha-MG uptake was blocked by mepacrine, a phospholipase A2 inhibitor. In addition, PT saponin increased [3H] arachidonic acid release by 218% of that of control, and this effect was also completely blocked by mepacrine. In conclusion, PT saponin inhibited, in part, alpha-MG uptake through the phospholipase A2 signal pathway in primary cultured rabbit renal PTCs.

Effect of ginsenoside-Rd in cephaloridine-induced renal disorder

To determine whether ginsenoside-Rd ameliorates the renal injury induced by cephaloridine, the effect of cephaloridine was investigated in rats given ginsenoside-Rd preceding cephaloridine administration and in control rats given no ginsenoside-Rd. In control rats, blood, renal and urinary parameters and the activities of antioxidative enzymes in renal tissue deviated from the normal range, indicating dysfunction of the kidneys. In contrast, when ginsenoside-Rd was given orally for 30 consecutive days prior to cephaloridine injection, the activities of the antioxidation enzymes superoxide dismutase and catalase were higher, while malondialdehyde levels in serum and renal tissue were lower in the treated rats than in the controls. The urea nitrogen and creatinine levels in serum were decreased in rats given ginsenoside-Rd. Decreased urine volume, increased urinary osmotic pressure, and decreased urinary levels of glucose, protein, sodium and potassium demonstrated a protective action against the renal dysfunction caused by cephaloridine. In addition, it was demonstrated that ginsenoside-Rd affected cultured proximal tubule cells exposed to cephaloridine.