Argininyl-Fructosyl-Galactose: A Novel Amino Acid Derivative improves Cisplatin-induced Intestinal Toxicity via Reactive Oxygen Species- mediated Apoptosis Pathway.

BACKGROUND: Based on the Maillard reaction principle of red ginseng, this study innovatively synthesized a new amino acid derivative by combining arginine with lactose through simulated synthesis and was separated and purified through repeated silica gel and polyacrylamide gel (Bio-gel P-II) column chromatography. PURPOSE: The work was aimed at elucidating the synthesis of a novel amino acid derivative and investigating the intestinal protective activity of the novel amino acid derivative and possible molecular mechanism by establishing the intestinal injury model induced by cisplatin in mice. METHODS: The purity and molecular weight of the amino acid derivatives were determined to be by electrospray ionization mass spectrometry (ESI-MS). Subsequently, by establishing cisplatin (20 mg/kg)-induced intestinal injury in vivo for 10 days and IEC-6 cell model. The biochemical indexes and histopathological analysis were used to evaluate the oxidative stress and inflammatory and pathological changes of intestinal tissue in mice. The protein expression levels of p-Nuclear transcription factor-κB (p-NF-κB), cleaved caspase 3/caspase 3, cleaved caspase 9/caspase-9, Bcl-2, Bax, cytochrome C, phosphatidylinositol 3-kinase (PI3K), Protein Kinase B (Akt), p-PI3K, p-Akt were quantified through immunofluorescence staining and western blot analysis. RESULTS: The new amino acid derivatives of chemical structure were identified to be 1- (arginine-Nαgroup)-1-deoxy-4-O-(ß-D-galactopyranosyl)-D-fructose, named Argininylfructosyl- galactose (AFGA, C18H34N4O12). The results showed that pretreatment with a single AFGA dose remarkably alleviated cisplatin-evoked intestinal oxidative stress injury, and the levels of reactive oxygen species (ROS) were lessening in IEC-6 cells (p<0.05, p<0.01) and could effectively reduce the secretion of TNF-α and IL-1ß in serum and the expression level of NF-κB protein in intestinal tissues (p<0.01). Meantime, AFGA also significantly suppressed the caspase 3, caspase 9, cytochrome C and Bax protein expression in intestinal tissue in mice (p<0.01), and regulated the PI3K/Akt pathway (p<0.05, p<0.01). Importantly, the molecular docking results of AFGA also suggested a better binding ability with the above-mentioned related target proteins. CONCLUSION: The results clearly revealed AFGA as a potential multifunctional therapeutic agent with a clear protective effect against cisplatin-induced intestinal injury may be related to the PI3K/Akt signaling pathway.

Preparation of a new resource food-arabinogalactan and its protective effect against enterotoxicity in IEC-6 cells by inhibiting endoplasmic reticulum stress.

Plant polysaccharides can be used as bioactive natural polymers that provide health benefits, however high molecular weight neutral polysaccharides have not shown good bioactivity. In this study, high molecular weight neutral arabinogalactan was isolated and structurally characterized to investigate it antioxidant activity against IEC-6 cells. In this study, a neutral polysaccharide (AG-40-I-II) was obtained from the roots of Larix gmelinii (Rupr.) Kuzen. and purified using ethanol fractional precipitation and purification on a DEAE-52 cellulose column and a Superose 12 gel filtration column. The structural characteristics of AG-40-I-II was detected by chemical and spectroscopic methods. The results showed that the average molecular weight of AG-40-I-II was 18.6 kDa, the main chain was composed of →4)-ß-D-Gal-(1, â†’ 4, 6)-ß-D-Gal-(1 and →4)-ß- D-Glc-(1, the side chain is composed of T-ß-L-Araf(1 â†’ 6). The effect of AG-40-I-II on H2O2-induced IEC-6 cell injury was determined by MTT method. Besides, AG-40-I-II could reduce the level of MDA and increase SOD activity on IEC-6 cells, which could significantly inhibit the production of ROS. Importantly, AG-40-I-II inhibited the splicing of XBP1 by IRE1α through the ERS pathway and reduced the cell apoptosis induced by H2O2. In summary, the results of this study indicate that AG-40-I-II, as a natural source of plant polysaccharides, has good antioxidant activity, and is expected to become a safe plant source of natural antioxidants, which has great potential in biomedicine potential.

AFG, an important maillard reaction product in red ginseng, alleviates D-galactose-induced brain aging in mice via correcting mitochondrial dysfunction induced by ROS accumulation.

Red ginseng is a classical processed product from Panax ginseng. C.A Meyer with many bioactive components formed through the Maillard reaction called Maillard reaction products. Maillard reaction refers to complex reversible reactions between amino acids or proteins and glycosides, which are used in food processing and storage, as well as in tobacco development, traditional Chinese medicine processing, and wine brewing. Arginyl-fructosyl-glucose (AFG) is a main non-saponin (ginsenoside) component produced in red ginseng processing, with high antioxidant, anti-apoptotic and neuroprotective efficiencies. However, its effects and mechanisms against oxidation stress in on the brain remain elusive. Therefore, this study aimed at exploring the therapeutic effect exerted by AFG on murine subacute brain aging induced by D-galactose (D-gal) and its potential molecular mechanism in the murine model, finding that AFG (40 and 80 mg/kg) significantly ameliorated D-gal-resulted changes in pathology. Besides, according to the transmission electron microscopy (TEM) and Western blot, AFG corrected the mitochondrial dysfunction resulted from ROS, thereby delaying the mice brain aging caused by D-gal.

20(S)-protopanaxatriol inhibited D-galactose-induced brain aging in mice via promoting mitochondrial autophagy flow.

Previous reports have confirmed that saponins (ginsenosides) derived from Panax ginseng. C. A. Meyer exerted obvious memory-enhancing and antiaging effects, and the simpler the structure of ginsenosides, the better the biological activity. In this work, we aimed to explore the therapeutic effect and underlying molecular mechanism of 20(S)-protopanaxatriol (PPT), the aglycone of panaxatriol-type ginsenosides, by establishing D-galactose (D-gal)-induced subacute brain aging model in mice. The results showed that PPT treatment (10 and 20 mg/kg) for 4 weeks could significantly restore the D-gal (800 mg/kg for 8 weeks)-induced impaired memory function, choline dysfunction, and redox system imbalance in mice. Meanwhile, PPT also significantly reduced the histopathological changes caused by D-gal exposure. Moreover, PPT could increase TFEB/LAMP2 protein expression to promote mitochondrial autophagic flow. Importantly, the results from molecular docking showed that PPT had good binding ability with LAMP2 and TFEB, suggesting that TFEB/LAMP2 might play an important role in PPT to alleviate D-gal-caused brain aging.

Valproic acid induced aplastic crisis and Stevens-Johnson syndrome in a single pediatric patient.

Valproic acid (VPA) is a commonly used antiepileptic drug (AED). Aplastic crisis is defined as acute arrest of hematopoiesis. Stevens-Johnson syndrome (SJS) is a fatal cutaneous adverse drug reaction. We herein report a rare case of aplastic crisis and SJS in a single pediatric patient that were probably caused by VPA. A 2-year-old girl was involved in a car accident. She was diagnosed with skull fractures, cerebral contusions, pulmonary contusions, and fractures of the left iliac bone by computed tomography. VPA was administered as prophylaxis for post-traumatic epilepsy. From day 13, she developed repeated high fevers, and multiple antibiotics were ineffective; she was then transferred to our pediatric intensive care unit. After transfer, she developed liver function impairment, decreased peripheral blood cell counts, and skin damage. After withdrawal of the VPA and administration of prednisone, intravenous immunoglobulin, local skin care, and nutritional support, her body temperature normalized and her hematopoietic function and skin lesions successively resolved. She was transferred out of the pediatric intensive care unit on day 56 and discharged on day 70. At the 6-month follow-up, a blood examination was normal, and repeat computed tomography revealed multiple softening foci of the bilateral brain and less subdural effusion than before. To our knowledge, no report to date has described aplastic crisis and SJS in a single patient. The purpose of this paper is to increase clinicians' knowledge in the treatment of adverse drug reactions (ADRs) and emphasize the importance of standardized application and strict monitoring of VPA in patients with post-traumatic brain trauma.

Evaluating the effects of mitochondrial autophagy flux on ginsenoside Rg2 for delaying D-galactose induced brain aging in mice.

BACKGROUND: Aging is an inevitable gradual process of the body, which can cause dysfunction or degeneration of the nervous or immune system, thus becoming a critical pathogenic factor inducing neurodegenerative diseases. Previous reports have confirmed that saponins (ginsenosides) derived from Panax ginseng. C.A. Meyer exerted obvious memory-enhancing and anti-aging effects, and the simpler the structure of ginsenosides, the better the biological activity. Ginsenoside Rg2 (Rg2) is a prominent and representative panaxatriol-type ginsenoside produced during ginseng processing, which has been reported to have pretty good neuroprotective activity. PURPOSE: The work was aimed at exploring the therapeutic effects and possible molecular mechanisms of Rg2 by establishing the subacute brain aging model induced by D-galactose (D-gal) in mice. METHODS: The anti-aging activity of G-Rg2 (10, 20 mg/kg for 4 weeks) was assessed using the D-gal induced brain aging model (800 mg/kg for 8 weeks). The Morris water maze (MWM) and histopathological analysis were used to evaluate the cognitive function and pathological changes of the brain in mice, respectively. The protein expression levels of p53, p21, p16ink4α, IL-6, CDK4, ATG3, ATG5, ATG7, LC3, p62, LAMP2, and TFEB were quantified through western blot analysis. The degree of mitochondrial damage and the number of mitochondrial autophagolysosomes in hippocampal neurons were monitored using TEM analysis. RESULTS: The results showed that Rg2 could significantly restore D-gal-induced impaired memory function, choline dysfunction, and redox system imbalance in mice. Rg2 treatment also considerably decreased the over-expression of aging-related proteins such as p53/p21/p16ink4α induced by D-galactose, which demonstrated that Rg2 possessed good anti-aging activity. Meanwhile, Rg2 could evidently reduce the pathological changes caused by D-gal exposure. Moreover, the results from transmission electron microscopy and western blot analysis indicated that Rg2 could delay the brain aging induced by D-gal in mice via promoting the degradation of the autophagy substrate p62 while increasing the protein expression level of LAMP2/TFEB to maintain mitochondrial function. CONCLUSION: These results indicate that Rg2 could postpone brain aging by increasing mitochondrial autophagy flux to maintain mitochondrial function, which greatly enriched the research on the pharmacological activity of ginsenosides for delaying brain aging.

Taxifolin retards the D-galactose-induced aging process through inhibiting Nrf2-mediated oxidative stress and regulating the gut microbiota in mice.

Aging and aging-related metabolic complications are global problems that seriously threaten public health. Taxifolin (TAX) is a novel health food and has been widely proved to have a variety of biological activities used in food and medicine. However, the delayed effect of TAX on the aging process has not been investigated. The purpose of this study is to explore the role of TAX as a natural active substance on aging brain tissue induced by D-galactose (D-Gal) and to determine the effect of supplementing TAX on the metabolism of the intestinal flora in aging bodies. The aging model was established by intraperitoneal injection of D-Gal (800 mg kg-1) once per 3 days for 12 weeks, and TAX (20 and 40 mg kg-1) was administered daily by oral gavage after 6 weeks of induction with D-Gal. After testing aging mice in an eight-arm maze, the results showed that TAX treatment significantly restored spatial learning and memory impairment. Moreover, long-term D-Gal treatment incited cholinergic dysfunction of aging mice, and H&E staining revealed obvious histopathological damage and structural disorder in the hippocampus of mouse brain tissue, while TAX treatment significantly reversed these changes. Importantly, supplementing with TAX significantly mitigated oxidative stress injury by alleviating the levels of reactive oxygen species (ROS) and malondialdehyde (MDA) while increasing antioxidant enzymes. Furthermore, TAX decreased the apoptosis of the aging brain by regulating the phosphorylation levels of phosphatidylinositol 3-kinase (PI3K), protein kinase B (AKT), and activating nuclear factor-erythroid 2-related factor 2 (Nrf2), nuclear heme oxygenase-1 (HO-1), and NADH dehydrogenase quinone 1 (NQO1) to maximally moderate the oxidative stress injury that occurred after D-Gal induction. In addition, 16S rDNA analysis revealed that TAX treatment decelerated the D-gal-induced aging process by regulating the composition of the intestinal flora and abundance of beneficial bacteria, including Enterorhabdus, Clostridium, Bifidobacterium, and Parvibacter. In conclusion, the results of this study demonstrated that TAX alleviated oxidative stress injury in mice aged by D-Gal and also confirmed that TAX improved the aging process by regulating intestinal microbes, which provides the possibility of prevention and treatment for aging and metabolic disorders through the potential food health factors.

[Synthesis and anti-tumor activity of ginsenoside Rh_2 caprylic acid monoester].

Ginsenoside Rh_2,firstly isolated from red ginseng,is protopanaxadiol type of steroidal saponin. Rh_2 possessed variety of activities,but bioavailability of oral administration Rh_2 was extremely low due to poor absorption. Moreover,ginsenoside Rh_2 exhibited toxicity on human normal cells. Therefore,to improve stronger anti-tumor activity and attenuate toxicity,it was essential to design and optimize chemical structure of ginsenoside Rh_2. Through n-octanoylchloride modifications,a novel ester derivative of ginsenoside Rh_2 named caprylic acid monoester of Rh_2( C-Rh_2) was designed and synthesized. Structure of novel ginsenoside derivative was identified by1 D and 2 D NMR,as well as ESI-MS analyses. Anti-tumor effect of C-Rh_2 was tested on H22 tumor bearing mice. C-Rh_2 displayed certain anti-tumor activities and exhibited less toxicity than Rh_2. In the present study,C-Rh_2 as ester form of ginsenoside Rh_2 showed better anti-tumor activity and less toxicity,but the specific mechanism needs further investigation.

Arginyl-fructosyl-glucose, a Major Maillard Reaction Product of Red Ginseng, Attenuates Cisplatin-Induced Acute Kidney Injury by Regulating Nuclear Factor κB and Phosphatidylinositol 3-Kinase/Protein Kinase B Signaling Pathways.

Recently, although ginseng ( Panax ginseng C. A. Meyer) and its main component saponins (ginsenosides) have been reported to exert protective effects on cisplatin (CDDP)-induced acute kidney injury (AKI), the beneficial activities of non-saponin on CDDP-induced AKI is little known. This research was designed to explore the protective effect and underlying mechanism of arginyl-fructosyl-glucose (AFG), a major and representative non-saponin component generated during the process of red ginseng, on CDDP-caused AKI. AFG at doses of 40 and 80 mg/kg remarkably reversed CDDP-induced renal dysfunction, accompanied by the decreased levels of serum creatinine and blood urea nitrogen. Interestingly, all of oxidative stress indices were ameliorated after pretreatment with AFG continuously for 10 days. Importantly, AFG relieved CDDP-induced inflammation and apoptosis in part by mitigating the cascade initiation steps of nuclear factor κB signals and regulating the participation of the phosphatidylinositol 3-kinase/protein kinase B signal pathway. In conclusion, these results clearly provide strong rationale for the development of AFG to prevent CDDP-induced AKI.

Human Gut Microbiota Associated with Obesity in Chinese Children and Adolescents.

OBJECTIVE: To investigate the gut microbiota differences of obese children compared with the control healthy cohort to result in further understanding of the mechanism of obesity development. METHODS: We evaluated the 16S rRNA gene, the enterotypes, and quantity of the gut microbiota among obese children and the control cohort and learned the differences of the gut microbiota during the process of weight reduction in obese children. RESULTS: In the present study, we learned that the gut microbiota composition was significantly different between obese children and the healthy cohort. Next we found that functional changes, including the phosphotransferase system, ATP-binding cassette transporters, flagellar assembly, and bacterial chemotaxis were overrepresented, while glycan biosynthesis and metabolism were underrepresented in case samples. Moreover, we learned that the amount of Bifidobacterium and Lactobacillus increased among the obese children during the process of weight reduction. CONCLUSION: Our results might enrich the research between gut microbiota and obesity and further provide a clinical basis for therapy for obesity. We recommend that Bifidobacterium and Lactobacillus might be used as indicators of healthy conditions among obese children, as well as a kind of prebiotic and probiotic supplement in the diet to be an auxiliary treatment for obesity.

Esterification enhanced intestinal absorption of ginsenoside Rh2 in Caco-2 cells without impacts on its protective effects against H2O2-induced cell injury in human umbilical vein endothelial cells (HUVECs).

Ginsenoside Rh2 and its octyl ester derivative (Rh2-O) were investigated for their transcellular transport in the Caco-2 cell system and their protective effect against oxidative stress in human umbilical vein endothelial cells (HUVECs). Results showed that the transport rates for apical-to-basolateral (AP-BL) flux of Rh2 (0.21 × 10⁻6 cm/s) was enhanced by the synthesis of its esterified derivative Rh2-O (1.93 × 10⁻6 cm/s) over the concentrations of 10-50 µM. In addition, both Rh2 and its esterified derivative Rh2-O exhibited similar protective effects against oxidative damage induced by H2O2. Pretreatment of Rh2 and Rh2-O significantly decreased the activation of caspase-3 known to play a key role in H2O2-induced cell apoptosis. These results were consistent with that of a flow cytometry assay analyzing HUVECs apoptosis. The present study demonstrated that the absorption of ginsenoside Rh2 in vitro can be significantly enhanced by synthesis of its ester derivative. Meanwhile, no significant discrepancy between Rh2 and Rh2-O on their bioactivities against the oxidative damage induced by H2O2 was observed, which means that esterification of Rh2 might have a higher bioavailability than Rh2 in vitro without impacts on pharmaceutical actions.

[Chemical constituents from fruit of Panax ginseng].

OBJECTIVE: To investigate chemical constituents from the ripe fruit of Panax ginseng. METHODS: The compounds were isolated and purified by chromatographic methods such as macroporous resin, sephadex LH-20, Bio-gel P-2, ODS and silica gel. Their structures were identified by their physical and spectral data(ESI-MS, 1H-NMR and 13C-NMR). RESULTS: Eleven compounds were isola- ted and identified as arginyl-fructose (1), arginyl-fructosyl-glucose (2), L-pyroglutamic acid (3), p-hydroxybenzoic acid (4), 5-hydroxy-methylfuraldehyde (5), ginsenosides Rb1 (6), Re (7), Rg1 (8), Rb2 (9), Rc (10) and daucosterol (11). CONCLUSION: Compounds 1-5 were obtained from the fruit of Panax ginseng for the first time.

Compound K is able to ameliorate the impaired cognitive function and hippocampal neurogenesis following chemotherapy treatment.

Chemotherapy frequently results in neurocognitive deficits that include impaired learning and memory. Thus, it is important to prevent or ameliorate the persistence of cognitive impairment. Compound K was employed to examine the ameliorating effect on chronic treatment with cyclophosphamide. Eight week-old ICR mice were given 80 mg/kg cyclophosphamide, cyclophosphamide combined with compound K (2.5, 5 and 10 mg/kg) or saline injections once per week for 4 weeks. Passive avoidance test and Y maze were used to evaluate memory and learning ability. Immunohistochemical staining for progenitor cell and immature neurons was used to assess changes in neurogenesis. Compound K (10 mg/kg) is able to ameliorate the decrease of neurogenesis in the hippocampus caused by cyclophosphamide. These results suggest that compound K might be a potential strategy to ameliorate or repair the disrupted hippocampal neurogenesis induced by the side effect of chemotherapy agent.

Antidiabetic effects of malonyl ginsenosides from Panax ginseng on type 2 diabetic rats induced by high-fat diet and streptozotocin.

ETHNOPHARMACOLOGY RELEVANCE: Ginseng (Panax ginseng C. A. Meyer) has been recorded to treat 'Xiao-ke' (emaciation and thirst) symptom in many ancient Chinese medical literatures (such as 'Shen Nong Ben Cao Jing') for thousands of years. 'Xiao-ke' symptom, in general, indicates diabetes mellitus. AIM OF THE STUDY: Malonyl ginsenosides (MGR) are natural ginsenosides which exist in both fresh and air-dried ginseng. The objective of this study is to determine the antidiabetic function of MGR on type 2 diabetes. MATERIALS AND METHODS: High fat diet-fed and streptozotocin-induced diabetic rats were treated with 50 and 100mg/kg/d of MGR or vehicle for 3 weeks. The effects of MGR on fasting blood glucose (FBG), intraperitoneal glucose tolerance test (IPGTT), serum insulin (SI), insulin tolerance test (ITT), body weight, total cholesterol (TC), and triglyceride (TG) levels in type 2 diabetic rats were measured. RESULTS: After 3 weeks of treatment, MGR administration showed significantly lower FBG levels compared to the diabetic control group. In glucose tolerance test, IPGTT data showed that both MGR 50 and 100mg/kg groups significantly increased the glucose disposal after glucose load. The ITT also showed improvement of insulin sensitivity during 120 min of insulin treatment. In addition, MGR reduced TG and TC contents while showed no effect on body weight in diabetic rats. CONCLUSION: The findings from this study suggest that MGR can alleviate hyperglycemia, hyperlipemia and insulin resistance of type 2 diabetes.

Absorption mechanism of ginsenoside compound K and its butyl and octyl ester prodrugs in Caco-2 cells.

Ginsenoside compound K (CK) is a bioactive compound with poor oral bioavailability due to its high polarity, while its novel ester prodrugs, the butyl and octyl ester (CK-B and CK-O), are more lipophilic than the original drug and have an excellent bioavailability. The aim of this study was to examine the transport mechanisms of CK, CK-B, and CK-O using human Caco-2 cells. Results showed that CK had a low permeability coefficient (8.65 × 10(-7) cm/s) for apical-to-basolated (AP-BL) transport at 10-50 µM, while the transport rate for AP to BL flux of CK-B (2.97 × 10(-6) cm/s) and CK-O (2.84 × 10(-6) cm/s) was significantly greater than that of CK. Furthermore, the major transport mechanism of CK was found as passive transcellular diffusion with active efflux mediated by P-glycoprotein (P-gp). In addition, it was found that CK-B and CK-O were not the substrate of efflux transporter since the selective inhibitors (verapamil and MK-571) of efflux transporter had little effects on the transport of CK-B and CK-O in the Caco-2 cells. These results suggest that improving the lipophilicity of CK by acylation can significantly improve the transport across Caco-2 cells.

Anti-diabetic effect of ginsenoside Rb(3) in alloxan-induced diabetic mice.

As one of the main active component of protopanaxdiol type ginsenosides, ginsenoside Rb(3) is rarely reported in the treatment of diabetes. The anti-diabetic activity of ginsenoside Rb(3) was investigated in a model of alloxan-induced diabetic mice in the present study. The physiological parameter such as fasting blood glucose level, oral glucose tolerance, body weight, food intake and water intake were measured. Glucose consumption in C2C12 myotubes was also determined in order to investigate the molecular mechanism of ginsenoside Rb(3) in anti-diabetes. The alloxan-induced diabetic mice were treated with ginsenoside Rb(3) for 2 weeks at doses of 5 mg/kg, 15 mg/kg and 25 mg/kg. After 2 weeks treatment of ginsenoside Rb(3), the fasting blood glucose levels of DG 15 and DG 25 were respectively reduced by 36.70% and 37.50% compared to control group. At a dose of 25 mg/kg, oral glucose tolerance was significantly improved compared to control group (P < 0.05). The AUC decreased by 34.47% (from 2442 ± 291 mmol·min/L to 1600 ± 109 mmol·min/L). Both food intake and water intake were remarkably lowered. The injury of pancreas tissues was repaired, which was observed by using HE staining and optic microscope. In vitro, at concentrations of 100 and 200 µM, ginsenoside Rb(3) increased glucose consumption in C2C12 myotubes by 76.83% and 97.20%, respectively, as compared to the control group. However, the body weight of diabetic mice was not significantly altered. In conclusion, our results showed that ginsenoside Rb(3) reduced fasting blood glucose level, food intake, water intake, improved oral glucose tolerance, and repaired injured pancreas tissues of alloxan-induced diabetic mice. Therefore, it was suggested that ginsenoside possesses the potential of the clinical use in preventing and treating diabetes.

Response surface methodology to optimize enzymatic preparation of Deapio-Platycodin D and Platycodin D from Radix Platycodi.

In the present work, we reported the enzymatic preparation of deapio-platycodin D (dPD) and platycodin D (PD) optimized by response surface methodology (RSM) from Radix Platycodi. During investigation of the hydrolysis of crude platycosides by various glycoside hydrolases, snailase showed a strong ability to transform deapio-platycoside E (dPE) and platycoside E (PE) into dPD and PD with 100% conversion. RSM was used to optimize the effects of the reaction temperature (35-45 °C), enzyme load (5-20%), and reaction time (4-24 h) on the conversion process. Validation of the RSM model was verified by the good agreement between the experimental and the predicted values of dPD and PD conversion yield. The optimum preparation conditions were as follows: temperature, 43 °C; enzyme load, 15%; reaction time, 22 h. The biotransformation pathways were dPE→dPD3→dPD and PE→PD3→PD, respectively. The determined method may be highly applicable for the enzymatic preparation of dPD and PD for medicinal purposes and also for commercial use.

Hypoglycemic effect of protopanaxadiol-type ginsenosides and compound K on Type 2 diabetes mice induced by high-fat diet combining with streptozotocin via suppression of hepatic gluconeogenesis.

Compound K (CK) is a final intestinal metabolite of protopanaxadiol-type ginsenosides (PDG) from Panax ginseng. Although anti-diabetic activity of CK have been reported with genetic mouse models (db/db mice) in recent years, the therapeutic usefulness of CK and PDG in type 2 diabetes, a more prevalent form of diabetes, remains unclear. In the present investigation, we developed a mouse of non-insulin-dependent diabetes mellitus that closely simulated the metabolic abnormalities of the human disease. For this purpose, type 2 diabetes was induced in male ICR mice by combining of streptozotocin. The male ICR mice fed with HFD for 4 weeks received 100mg/kg of STZ injected intraperitoneally. After 4 weeks, mice with fasting (12h) blood glucose levels (FBG) above 7.8 mmol/L were divided into 3 groups (n=12) and treated with vehicle (diabetes model, DM), 300 mg/kg/day of PDG and 30 mg/kg/day of CK for 4 weeks while continuing on the high-fat diet. Hypoglycemic effects of CK and PDG were consistently demonstrated by FBG levels, and insulin-sensitizing effects were seen during oral glucose tolerance testing (OGTT). Moreover, the mechanism of hypoglycemic effect in type 2 diabetic mice was examined. Gluconeogenic genes, Phosphoenolpyruvate carboxykinase (PEPCK) and Glucose-6-phosphatase (G6Pase), were decreased in two treatment groups with CK showing greater effects. These findings demonstrated the hypoglycemic and insulin-sensitizing capabilities of CK on type 2 diabetes induced by HFD/STZ via down-regulation of PEPCK and G6Pase expression in liver.

Structural modification of ginsenoside Rh(2) by fatty acid esterification and its detoxification property in antitumor.

Ginsenoside Rh(2), one of the most important ginsenosides with anticancer properties in red ginseng, has been developed as principal antitumor ingredient for clinical use. However, the cytotoxicity test in human hepatocyte cell line QSG-7701 (IC(50) 37.3µM) indicated that Rh(2) might show strong cytotoxic side-effect on the normal liver cells. For blunting the toxicity, Rh(2) was structurally modified by reacting with octanoyl chloride to give a dioctanoyl ester of Rh(2) (D-Rh(2)) in the present study. MTT assay in QSG-7701 cell line in vitro showed that the cytotoxicity of D-Rh(2) on human hepatocyte cells (IC(50) 80.5µM) was significantly lower than that of Rh(2). While antitumor xenograft assay in mice bearing H22 liver cancer cells in vivo showed that the antitumor activity of D-Rh(2) retained to be strong as that of Rh(2). According to previous pharmacokinetic studies, the fatty acid esterification of Rh(2) might be of detoxification reaction to cells. Additionally, D-Rh(2) showed significant enhancement on increasing thymus index at the dose of 10mg/kg compared with vehicle treated control group. Thus, D-Rh(2) might indirectly affect tumor growth by stimulating lymphocytes to become cytotoxic to tumor cells. Finally, our findings suggested that D-Rh(2), the fatty acid ester of Rh(2), might attenuate the side-effect by detoxification to human normal cell and could be a more potential candidate for developing as an antitumor drug.

Snailase preparation of ginsenoside M1 from protopanaxadiol-type ginsenoside and their protective effects against CCl4-induced chronic hepatotoxicity in mice.

To investigate the protective effects of protopanaxadiol-type ginsenoside (PDG) and its metabolite ginsenoside M1 (G-M1) on carbon tetrachloride (CCl(4))-induced chronic liver injury in ICR mice, we carried out conversion of protopanaxadiol-type ginsenosides to ginsenoside M1 using snailase. The optimum time for the conversion was 24 h at a constant pH of 4.5 and an optimum temperature of 50 °C. The transformation products were identified by high-performance liquid chromatography and electrospray ion-mass spectrometry. Subsequently, most of PDG was decomposed and converted into G-M1 by 24 h post-reaction. During the study on hepatoprotective in a mice model of chronic liver injury, PDG or G-M1 supplement significantly ameliorated the CCl(4)-induced liver lesions, lowered the serum levels of select hepatic enzyme markers (alanine aminotransferase, ALT, and aspartate aminotransferase, AST) and malondialdehyde and increased the activity of superoxide dismutase in liver. Histopathology of the liver tissues showed that PDG and G-M1 attenuated the hepatocellular necrosis and led to reduction of inflammatory cell infiltration. Therefore, the results of this study show that PDG and G-M1 can be proposed to protect the liver against CCl(4)-induced oxidative injury in mice, and the hepatoprotective effect might be attributed to amelioration of oxidative stress.