Simultaneous quantification of ginsenoside Rg1 and its metabolites by HPLC-MS/MS: Rg1 excretion in rat bile, urine and feces

Ginsenoside Rg1 (Rg1), the major effective component of ginseng, has been shown to have multiple bioactivities, but low oral bioavailability. The aim of this study was to develop a simple, sensitive and rapid high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, which could be used to validate and quantify the concentrations of Rg1 and its metabolites in Sprague-Dawley rat bile, urine, and feces after oral administration (25 mg/kg). Calibration curves offered satisfactory linearity (>0.995) within the determined ranges. Both intra-day and inter-day variances were less than 15%, and the accuracy was within 80-120%. The excretion recoveries of Rg1, ginsenoside Rh1 (Rh1), and protopanaxatriol (Ppt) in bile, urine, and feces combined were all greater than 70%. The fecal excretion recoveries of Rg1, Rh1, and Ppt were 40.11%, 22.19%, and 22.88%, respectively, whereas 6.88% of Rg1 and 0.09% of Rh1 were excreted in bile. Urinary excretion accounted for only 0.04% of Rg1. In conclusion, the observed excretion profiles for Rg1 and its metabolites after oral administration are helpful for understanding the poor oral bioavailability of Rg1 and will aid further investigations of Rg1 as a pharmacologically active component.

Epigenetic mechanism in cognitive function / 中国药理学通报

The definition of epigenetics and its cellular basis are introduced firstly in the paper. Then, the research progress on the relationship between cognition and epigenetic changes is re-viewed in detail. In conclusion, epigenetic modifications occur-ring in hippocampus, cortex and other brain areas such as methy-lation , phosphorylation , ubiquitination , poly ( ADP-ribos ) poly-merases and DNA methylation may certainly change animal be-haviors including learning, memory, synaptic plasticity, depres-sion, drug abuse and so on. Long-term memory and long-term potentiation( LTP) , activation of AMPK-ERK signal transduction path-way and activation of key gene regulated by CREB-ABP transcriptional complex as well as transcription and expression of memory and synaptic plasticity related genes ( Zif/268, Creb, Bdnf, reelin ) are required. In contrast, epigenetic abnormal changes such as histone and DNA hypomethylation and increase of HDAC activity are observed in brains of aging and neurodegen-erative diseases. Therefore, the main epigenetic treatments for cognitive impairments are increasing histone and DNA methyla-tion, using HDAC inhibitors and RNA interference ( RNAi) to promote formation of long term memory and long term potentia-tion, block learning and memory decline.

Salvianolic acid B alleviate the disruption of blood-brain barrier in rats after cerebral ischemia-reperfusion by inhibiting MAPK pathway / 药学学报

The aim of the study is to investigate the effect of salvianolic acid B (SalB) on blood-brain barrier (BBB) in rats after cerebral ischemia-reperfusion, and to illustrate its possible mechanisms. Cerebral ischemia-reperfusion was induced by middle cerebral artery occlusion in rats. The break-down of BBB was indicated by extravasations of immunoglobulin (IgG) monitored with immunohistochemistry. The expression of MMP-9 and NOS2 in the brain was determined by immunohistochemistry, and the expression of p-p38 and p-ERK1/2 was detected by Western blotting. It was shown that on day 2 after ischemia-reperfusion the IgG accumulated around the vascular boundary zone, suggesting the break-down of BBB, and the expression of MMP-9 and NOS2 up-regulated at the same time. The result of Western blotting suggested that the expression of p-p38 and p-ERK1/2 increased. On day 7 after ischemia-reperfusion the. expression of MMP-9 and NOS2 was about the same level as day 2, the expression of p-p38 was higher than that on day 2 and the expression of p-ERK1/2 was slightly lower than that on day 2. SalB (1 and 10 mg x kg(-1)) significantly alleviated the extravasations of immunoglobulin induced by cerebral ischemia-reperfusion (P < 0.05). On day 2 and day 7 SalB attenuated the expression of MMP-9 and NOS2 (P < 0.05). SalB (10 mg x kg(-1)) reduced the expression of p-p38 and p-ERK1/2 apparently on day 2 and 7 after ischemia-reperfusion (P < 0.05). SalB (1 mg x kg(-1)) inhibited the expression of p-p38 on day 7 after ischemia-reperfusion (P < 0.05). The results indicate that SalB protects blood-brain barrier in rats after cerebral ischemia-reperfusion by inhibiting the MAPK pathway.

Comparison of pharmacological effects of ginsenoside Rg1 and Rb1 / 基础医学与临床

Ginseng has long been used as a tonic and agent for prolonging life span in chinese traditional medicine． Using morden technology，ginsenoside Rgl and Rbl were proved to be main active principles of ginseng．Both conpounds showed the same effect in improving learning and memory， increasing Bmax of M-cholinergic receptors and accelerating cerebral protein and acetylcholine biosynthesis．However，Rgl but not Rbl had immunoregulatory action in aged rats and anti-osteoporosis effect in ovariectomized rats as well as enhanced basic synaptic transmission and magnitude of LTP induced by HFS． On the other hand，Rbl had anti-stress effects in antagonizing acute,chronic and repeated stress induced reduction of sexual behaviour and decrease of plasma andogen or estrogen．Rgl showed no such effect even aggravate stress induced damage．Rhl possessed anti-oxidant activity and prolong survival time of mice in cold(－10℃) condition．There was no any anti-cold effect with Rgl .These diference of biological activities between Rgl and Rbl may be arributed to their structures containing different number of glucoses．

Water soluble active ingredients of Danshen--review on the Salvianolic acids / 基础医学与临床

Danshen-Radix Salviae Miltiorrhizae，is one of the common traditional Chinese medicines，which has been used clinically in the treatment of cardiovascular diseases more than 20 centuries.The active ingredients of Danshen has been researched 5 decades by the modern methods.Many researchers investigated the pharmacological effects of water soluble ingredients of Danshen-salvianolic acids in vivo and in vitro.The results demonstrated that salvianolic acids have different pharmacological effects such as potent antioxidative effects，scavenging free radicals，protect neural cells against injuries caused by anoxia， etc.In present paper，the pharmacological effects of salvianolic acids and the mechanisms of their actions are reviewed based on the research results obtained in our laboratory and other authors.

The advance on study of melatonin atntioxidative effect / 中国药理学通报

Melatonin (MT) is secreted by the pineal gland and has obvious biological rhythmicity including circadian, season rhythm and life rhythm (aging clock). The reduction of MT secretion is related to body aging, particularly in close relation to brain aging. The hypothesis of aging is involved in pineal calcification, biological clock, neuro-en-docrinoimmunology, and free radical damage. MT is an endogenous free radical scavenger, may anto-gonize the attack of hydroxyl free radical ( ?OH)on organism and glutamate (Glu) excitotoxicity, and has a potent protective effect of central nervous system. In vivo studies showed that the food restriction and exogenous MT could obviously prolong life, postpone aging, and reduce the chances of age-related diseases. Investigating of MT anti-aging effect shows a vast prospect.

Progress in synaptic plasticity and related proteins / 中国药理学通报

The growth associated protein(GAP 43) and neural cell adhesion molecule (NCAM) play an important role both in promoting neurite outgrowth and synaptic plasticity. GAP 43 is a neuron specific phosphoprotein that is highly expressed during the development of the central nervous system, nerve regeneration and the modulation of synaptic function, and it is frequently used as a marker for sprouting. GAP 43 may be involved in G protein interaction, membrane binding, calmodulin binding and protein kinase C phosphorylation. The various interactions, specified by the structural domains, are thought to underlie the role of GAP 43 in synaptic plasticity, participating in membrane extension during neuritogenesis, in neurotransmitter release and long term potentiation. NCAMs involve in the intracellular signaling cascades and stimulate the axonal growth, GAP 43 function is essential for NCAM stimulated neurite outgrowth and that much of this appears because of the phosphorylation of GAP 43 via the FGF receptor dependent stimulation of arachidonic acid. NCAM can accelerate the phosphorylation of GAP 43.

Progress in stem cell research / 中国药理学通报

Stem cells exist not only in the developing mammalian embryo but also in certain areas of various adult tissues. In embryo, they can take part in the development of tissues and the whole organism while in adult, they are thought to be involved in cell metabolism. With the development of research in embryo and nervous system, the field of stem cells has become a hot point in scientific world. A brief summary is made on stem cell biology and its potential medical importance.

Effects of salvianolic acids on endothelial cells against damage induced by cholestane-3beta-5alpha-6beta-triol / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the effects of salvianolic acids on human umbilical vein endothelial cells (HUVEC) against damage induced by cholestane-3beta-5alpha-6beta-triol (chol-triol).</p><p><b>METHODS</b>The viability of HUVEC was measured by MTT method. The apoptosis of HUVEC induced by chol-triol was detected by flow cytometry and TUNEL assay. The production of malondialdehyd (MDA) in HUVEC was tested by thiobarbaturic acid (TBA) assay.</p><p><b>RESULTS</b>The viability of HUVEC treated with chol-triol 100 micro mol/L decreased by 39.8% while salvianolic acids 100 micro g/ml increased by 27.9%. The apoptotic rate of HUVEC measured by PI staining increased from 6% - 8% to 17% - 20% after chol-triol treatment for 12 h. Salvianolic acids 100 micro g/ml reduced the apoptotic rate to 10% - 14% after treatment HUVEC for 1 h prior to chol-triol treatment. In another experiment, chol-triol increased the number of TUNEL-positive cells 5 times, but salvianolic acids 10 micro g/ml and 100 micro g/ml reduced the number of TUNEL-positive cells by 36.9% and 61.2%, respectively. The production of MDA in HUVEC increased by 120.7% after chol-triol treatment for 12 h. Salvianolic acids 10 micro g/ml and 100 micro g/ml also decreased the concentration of MDA by 28.7% and 39.8%, respectively.</p><p><b>CONCLUSION</b>Salvianolic acids has protective effect on endothelial cells against damage induced by chol-triol.</p>

Research of the activity and the inhibitors of cGMP specific PDE5 / 中国生化药物杂志

Purpose　The aim is to study the activity and the sildenafil selective inhibition of PDE5. Methods　The PDE isoenzymes were purified from bovine penis corpus cavernosum tissue by FPLC system. PDE activity was assayed by using 3　H-cGMP as substrate, the PDE isoenzymes hydrolyzed it to 3　H-GMP, and 3　H-GMP was further hydrolyzed to 3　H-guanosine by 5′-nuclease of snake venom. Add scintillation cocktail to observe the PDE isoenzymes activity. The selective inhibitor sildenafil of different concentrations were used to observe the inhibition of PDE5. Data replotted according to procedure of Dixon plots.Results　Three PDE isoenzyme peaks were purificated from bovine corpus cavernosum. The PDE of the third peak had the strongest activity of cGMP hydrolyzation which could be inhibited by sildenafil apparently.Conclusion　Since PDE5 was mainly found in corpus cavernosum tissue of mammalian, and sildenafil was a selective inhibitor of PDE5. It was suggested that the third peak was PDE5. The result was in agreement with the article reported.

The relationship between sulfated polysaccharides and atheroscle rosis / 中国药理学通报

The atherogensis was involved in a complex pathological process. Injury to endothelial cells of blood vessels was confirmed to be the in itial stage of this process. Migration to subendothelial layer and accumulation and proliferation of smooth muscle cells were attributed to various cytokines an d adhesive molecules secreted by activated endothelial cells, subsequently resul ting in aggregation of lymphocytes,platelets, monocytes and macrophages in the i ntima of artery. These cellular components ultimatedly led to the formation of a mature atherosclerotic plaque. Its quite acknowledged that a better understan ding of the atherogenic events might promise us the development of new chemical entities of anti-atherosclerotic therapies. A large body of evidence has demons trated that sulfated polysaccharides played a critical role in the development o f atherosclerosis. The underlying mechanisms of the anti-atherosclerotic activi ty of sulfated polysaccharides were reported to contribute to protecting against endothelial cells injury,inhibiting migration and proliferation of vascular smo oth muscle cells, and reducing the adhesion of inflammatory cells, platelets and lymphocytes. And also, the prevention of complement activation by sulfated poly saccharides could not be excluded. On the other hand,the promoting effects of su lfated polysaccharides atherosclerosis was also reported. Its therefore conclu ded that the relationships between atheriosclerosis and sulfated polysaccharides remained to be further elucidated.

EFFECT OF GINSENOSIDE Rg1 ON LEARNING AND MEMORY IMPAIRMENT INDUCED BY β-AMYLOID PEPTIDE(25-35) AND ITS MECHANISM OF ACTION / 药学学报

AIM　To study the effect of ginsenoside Rg1 on the learning and memory impairment in mice induced by aggregated β-AP(25-35). METHODS　Mice were administered Rg1 (5, 10 mg*kg-1, ip) for 10 d and control mice received daily ip injections of saline after the intracerebroventricular injection of aggregated β-AP(25-35). After the final treatment, passive avoidance and performance in the Morris water maze (MWM) were assessed. and the activity of cortical and hippocampal ChAT and AchE were detected after the final behavior test. RESULTS　Ginsenoside Rg1 (5, 10 mg*kg-1, ip) significantly ameliorated the learning and memory impairment induced by β-AP(25-35). Rg1 (5, 10 mg*kg-1) decreased the latencies and swim distances of mice to reach a hidden platform and improved the corresponding changes in search strategies occurred in the Morris water maze, and Rg1 (10 mg*kg-1, ip), increased step-through latencies also. Biochemical analysis showed that Rg1 (5, 10 mg*kg-1, ip) prevented the cortical and hippocampal ChAT activity decline induced by β- AP(25-35), and showed inhibition of the activity of AchE, although β-AP(25-35) showed no effect on the cortical and hippocampal AchE activity. CONCLUSION　These data showed that ginsenoside Rg1 significantly improved the learning and memory impairment induced by β-AP(25-35), and this effect could be attibuted to its inhibition of AchE and increase of ChAT activity.

Stress and reproductive endocrine dystunction / 中国药理学通报

Physical and psychological stresses inhibit or harm reproductive endocrine especially female one at many levels of hypothalamo-pituitary-gonadal (HPG) axis, and result in subhealth conditions or clinic diseases in reproductive endocrine. The hypothalamic corticotropin-releasing factor (CRF) and adrenal glucocorticoids (GCS) overreleases and other neuroendocrine alterations induced by stress are implicated in the mechanisms responsible for the disturbance of reproductive endocrine. The declines in activities of synzyms for reproductive hormones cause sexual hormones reduces and disfunction in reproductive endocrine system.

Clinical applications of misoprostol / 中国药理学通报

Misoprostol, a prostaglandin E1 analogue, have variety clinical applications. In early 80's, misoprostol is currently licensed primarily to prevent non-steroidal anti-inflammatory drug-associated gastric and duodenal ulcers. Further work shows the drugs have protection to hepatic and renal and prevention of inflammatory and allergic disorders. When combined with mifepristone,complete abortion rate is 95%. On the other hand, misoprostol is also an effective agent for cervical ripening and labor induction. It have no serious side effect, as a result, misoprostol is a drug of high effect and low toxicity, deserving popularization, but man and pregnant woman must prudent.

Effect and mechanism of sildenafil on rabbit corpus cavernosum in vitro / 中国药理学通报

AIM To study the effect and mechanism of sildenafil on rabbit corpus cavernosum in vitro . METHOD Rabbit corpus cavernosum(RCC) segments were incubated with various concentrations of sildenafil. The formation of cGMP was stimulated with 1 ?mol?L -1 sodium nitroprusside(SNP), and the cyclic GMP concentration was measured by radioimmunoassy technology. In the organ bath, strips of RCC were precontracted with 10 ?mol?L -1 phenylephrine. Sildenafil were added with increasing doses gradually, graded relaxations were induced using various concentrations of sodium nitroprusside (SNP) and methacholine (MCH). RESULT In the presence of SNP, the cGMP concentration was increased in rabbit penile tissue, the increase of cGMP was greater when sildenafil was added. Sildenafil 10、100 nmol L -1 、1 ?mol?L -1 dose-dependently relaxed RCC strips. CONCLUSION Sildenafil increases cGMP concentration in RCC is attributed to the augmentation of NO/cGMP pathway, and the accumulation of cGMP improves the relaxation of RCC.

The relationship between sulfated polysaccharides and atherosclerosis / 中国药理学通报

The atherogensis was involved in a complex pathological process. Injury to endothelial cells of blood vessels was confirmed to be the initial stage of this process. Migration to subendothelial layer and accumulation and proliferation of smooth muscle cells were attributed to various cytokines and adhesive molecules secreted by activated endothelial cells, subsequently resulting in aggregation of lymphocytes, platelets, monocytes and macrophages in the intima of artery. These cellular components ultimatedly led to the formation of a mature atherosclerotic plaque. It's quite acknowledged that a better understanding of the atherogenic events might promise us the development of new chemical entities of anti-atherosclerotic therapies. A large body of evidence has demonstrated that sulfated polysaccharides played a critical role in the development of atheroscle- rosis. The underlying mechanisms of the antiatherosclerotic activity of sulfated polysaccharides were reported to contribute to protecting against endothelial cells injury, inhibiting migration and proliferation of vascular smooth muscle cells, and reducing the adhesion of inflammatory Cells, platelets and lymphocytes. And also, the prevention of complement activation by sulfated polysaccharides could not be excluded. On the other hand, the promoting effects of sulfated polysaccharides atherosclerosis was also reported. It's therefore concluded that the relationships between atherioscierosis and sulfated polysaccharides remained to be further elucidated.

Nucleotide signals in the central nervous system and microglial movements / 中国药理学通报

Microglia cells are immune cells in the central nervous system.When the microenvironment of brain has changed,microglia will respond rapidly.ATP,UTP,or other nucleotide signals released by neurons from damaged site and their metabolites such as ADP,adenosine,UDP and so on will bind with the purinergic receptors on microglia to regulate the morphology and function of microglia,then the microglial cells activated by nucleotide signals are to regulate neural cells by phagocytosis or releasing cytokines.In this article,the function and corresponding mechanisms of nucleotide signals on chemotaxis,phagocytosis,and process retraction are reviewed.

Protective effect of total salvianolic acid against cerebral ischemia-reperfusion injury / 中国药理学通报

AIM To study the protective effect of total salvianolic acid against cerebral ischemia reperfusion injury. METHODS The cerebral ischemia reperfusion model in mice was made by means of ligating bilateral common carotid arteries in mice. After reperfusion, latency, error number of step down test and the gasping time after cutting head in ischemia reperfusion mice were recorded. Spectrophotometric assay were used to measure the activity of superoxide dismutase (SOD), the contents malondialdehyde (MDA) and glutathione peroxidase (GSH) in brain of experimental mice brain homogenate. RESULTS In step down test, the ischemia reperfusion impaired the function of learning and memory in mice. The total salvianolic acid markedly improved the function of learning and memory, reduced the error number and extended the latency in ischemia reperfusion mice. The total salvianolic acid also significantly inhibited the changes of SOD, MDA and GSH in the cerebrum induced by ischemia reperfusion. CONCLUSION The total salvianolic acid has protective effect against cerebral ischemia reperfusion injury via its antioxidant activity.

Protective effects of total salvianolic acid against cerebral ischemia-reperfusion injury / 中国药理学通报

AIM To study the protective effect of total salvianolic acid against cerebral ischemia reperfusion injury. METHODS The cerebral ischemia reperfusion model in mice was made by means of ligating bilateral common carotid arteries in mice. After reperfusion, latency, error number of step down test and the gasping time after cutting head in ischemia reperfusion mice were recorded. Spectrophotometric assay were used to measure the activity of superoxide dismutase (SOD), the contents of malondialdehyde (MDA) and glutathione peroxidase (GSH) in brain of experimental mice brain homogenate. RESULTS In step down test, the ischemia reperfusion impaired the function of learning and memory in mice. The total salvianolic acid markedly improved the function of learning and memory, reduced the error number and extended the latency in ischemia reperfusion mice. The total salvianolic acid also significantly inhibited the changes of SOD, MDA and GSH in the cerebrum induced by ischemia reperfusion. CONCLUSION The total salvianolic acid has protective effects against cerebral ischemia reperfusion injury via its antioxidant activity.

The relationships between senile plaques, neurofibrillary tangles and sulfated polysaccharides / 中国药理学通报

Two aberrant structures, extracellular senile plaques (SP) and intracellular neurofibrillary tangles (NFTs) are the characteristic neuropathological hallmarks of Alzheimers disease (AD). Amyloid ? protein (A?) and hyperphosphorylated tau protein are the major components of SP and NFTs respectively. A large body of evidence has highlighted the pivotal role of sulfated polysaccharides in the amyloidogenesis and formation of NFTs. The underlying mechanisms of the involvement of sulfated polysaccharides in the development of AD were reported to contribute to their high affinity for both A? and tau protein. Sulfated polysaccharides not only promoted the ? secretase cleavage of APP and the increased production of A? and induced the aggregation and deposition of A?, but also facilitated the phosphylation of tau and promoted tau polymerization into fibrils and tangle formation. On the other hand, the neurotrophic effects exerted by sulfated polysaccharides were also demonstrated. These notions were probably due to the inhibition of the formation of A? fibrils or to the counteraction of the abnormal phosphorylation of tau by promoting the protein phosphatase2B activity, which has been speculated to be attributed to the variation in either structural backbone or degree of sulfation or position of sulfation. Putting together, the appropriate structural modification of sulfated polysaccharides may be effective as therapeutic agents for AD.