Effect of ginsenoside Rb1 and compound K in chronic oxazolone-induced mouse dermatitis

During the screening program to discover antipsoriatic agents from natural products, ginseng was found to show inhibitory activity in oxazolone-induced mouse ear dermatitis. Therefore, the effects of a main constituent ginsenoside Rb1 isolated from ginseng and its metabolite compound K on oxazolone-induced mouse ear dermatitis were investigated. Compound K at concentrations of 0.02% and 0.05% also potently suppressed mouse ear swelling by 54% and 76% at 16 days, respectively, although ginsenoside Rb1 did not significantly show the inhibitory activity. The compound K also significantly reduced the levels of mRNA of cyclooxygenase (COX)-2, IL-1beta, TNF-alpha, IFN-gamma and IL-4 increased in oxazolone-applied mouse ears. Based on these findings, the compound K may improve contact dermatitis or psoriasis by the regulation of COX-2 produced by macrophage cells and interferon-gamma and IL-4 induced by Th cells.     

人参皂苷CK对咪喹莫特诱导小鼠银屑病的治疗作用

目的探讨人参皂苷CK(ginsenoside metabolite compound K,GCK)对银屑病小鼠模型的治疗作用和机制。方法随机将咪喹莫特(imiquimod,IMQ)诱导的银屑病模型小鼠分为:模型组、GCK(14、28、56、112 mg·kg^-1)组、甲氨蝶呤(methotrexate,MTX,2 mg·kg^-1)组、地塞米松(dexamethasone,DEX,5 mg·kg^-1)组,连续灌胃给药7 d。同时设正常对照组,灌胃等量溶媒。银屑病皮损面积和疾病严重程度(psoriasis area and severity index,PASI)评分评价皮损严重程度;HE染色观察皮肤病理变化;免疫组化法分析皮损处细胞核增殖抗原(proliferating cell nuclear antigen,PCNA)表达;Western blot检测角蛋白1(cytokeratin-1,K1)的表达及JAK1、JAK2、p-JAK1、p-JAK2、STAT3、p-STAT3的表达;ELISA检测小鼠皮损处IL-23、IL-17水平。结果与模型组相比,GCK降低PASI评分,改善皮损病理变化,减少PCNA的表达,升高K1的表达,降低IL-23、IL-17水平,抑制JAK1/2-STAT3磷酸化。结论GCK对小鼠银屑病模型的作用机制可能与影响IL-23/IL-17-JAK1/2-STAT3信号通路有关。     

RP-HPLC同时测定复方三七制剂中的人参皂苷Rg1、Rb1

目的 建立复方三七制剂中人参皂苷Rg1、Rb1含量测定的方法.方法 采用RP-HPLC法,色谱柱为Phenomenex C18(250 mm x4.6 mm,5 μm);流速1.0 ml·min-1;检测波长203 nm;柱温30℃;流动相为乙腈-水(梯度洗脱).结果 人参皂苷Rg1的线性范围为0.2124～2.1240 μg(r=0.9999),平均回收率为100.24%,RSD=1.14%(n=9);人参皂苷Rb1的线性范围为0.2108～2.1080μg(r=0.9999),平均回收率为99.71%,RSD=0.79%(n=9).结论 所建方法简便、准确,重复性好,可同时测定复方三七制剂中人参皂苷Rg1和人参皂苷Rb1的含量.     

人参皂苷Rg1对小鼠1—甲基—4—苯基—1，2，3，6—四氢吡啶诱导的黑质神经元凋亡的保护作用

目的:探讨人参皂苷Rg1对抗1-甲基-4-苯基-1,2,3,6-四氢吡啶(MPTP)诱导的C57BL小鼠黑质神经元凋亡的可能机制.方法:MPTP(30 mg·kg~(-1)·d~(-1)×5 d)腹腔注射制备C57BL小鼠帕金森病模型,同时预防组分别以不同剂量人参皂苷Rg1(2.5、5.0、10.0 mg·kg~(-1)·d~(-1)×8 d)于MPTP注射前预先腹腔注射小鼠.用Nissl染色和TH组化染色观察黑质损害情况,TUNEL染色检测细胞凋亡,同时运用免疫组织化学方法检测caspase-3的活性片段以及Bcl-2、Bcl-xl、Bax、iNOS和 nNOS的表达情况.结果:人参皂苷Rg1(5.0和10.0 mg/kg)预处理能使黑质致密带Nissl阳性神经元和TH阳性神经元的脱失减少,同时降低了TUNEL阳性率,并伴有Bcl-2和Bcl-xl表达增加,Bax和iNOS表达减少以及抑制caspase-3的激活.结论:人参皂苷Rg1预处理对MPTP诱导的小鼠黑质神经元凋亡有明显的保护作用,其作用可能是通过降低iNOS和Bax蛋白表达,增加Bcl-2和Bcl-xl蛋白表达以及抑制caspase-3的激活来实现的.     

The effects of ginsenoside Re and its metabolite, ginsenoside Rh1, on 12-O-tetradecanoylphorbol 13-acetate- and oxazolone-induced mouse dermatitis models

The effects of the main constituent ginsenoside Re in ginseng and its metabolite, ginsenoside Rh1, were investigated in 12-O-tetradecanoylphorbol 13-acetate (TPA)- and oxazolone-induced mouse ear dermatitis models. Ginsenoside Rh1 potently suppressed the TPA- and oxazolone-induced swellings as well as mRNA expression levels of cyclooxygenase-2, IL-1beta and TNF-alpha, although these were only weakly inhibited by ginsenoside Re.     

Red ginseng inhibits scratching behavior associated with atopic dermatitis in experimental animal models

Pruritus is a severe symptom that is difficult to treat in atopic dermatitis patients. Red ginseng (RG), a natural medicine, has various biological activities such as anti-inflammatory effects. In this study, we examined the efficacy of RG extract (RGE) and its mechanism on experimental atopic dermatitis in mice. The effects of RGE on vascular permeability and itching were first evaluated. Histamine-induced permeability and itching were significantly inhibited by embrocation with RGE as well as diphenhydramine, an antihistamine drug. Next, we assessed the therapeutic effect of topical RGE in a mouse model of atopic dermatitis. Dermatitis was induced by repeated application of 2,4-dinitrofluorobenzene (DNFB) acetone solution to the mouse ear. The effects of tacrolimus (a calcineurin blocker), dexamethasone (a corticosteroid), and RGE on dermatitis and associated scratching behavior were compared. Repeated DNFB application caused frequent scratching behaviors and ear swelling. Topical treatment with tacrolimus, dexamethasone, and RGE for 8 days before the final challenge with DNFB significantly inhibited ear swelling. Tacrolimus and RGE significantly inhibited scratching behavior, whereas dexamethasone failed to do so. DNFB-induced nerve growth factor expression and nerve fiber extension were significantly attenuated by tacrolimus and RGE, but not by dexamethasone. RGE may have the potential for treatment of atopic dermatitis.     

Effect of Brazilian propolis on scratching behavior induced by compound 48/80 and histamine in mice

We studied the effect of Brazilian propolis on scratching behavior induced by compound 48/80 and histamine in ICR mice. Propolis granular A.P.C dose-related inhibited scratching behavior induced by compound 48/80 and significant inhibition were observed at 1000 mg/kg. However, histamine-induced scratching behavior was not inhibited by propolis granular A.P.C even at 1000 mg/kg. Propolis ethanol extract at 10 microg/ml or more inhibited histamine release from rat mast cells induced by compound 48/80. In addition, it blocked increased vascular permeability induced by compound 48/80. The inhibitory effect of propolis on scratching behavior induced by compound 48/80 was gradually enhanced by repeated administration, and 500 mg/kg propolis granular A.P.C, which caused no effect through single administration, significantly inhibited scratching behavior after repeated administration for 4 weeks. From these findings, it is assumed that the inhibition of scratching behavior induced by propolis occurs through a mast cell-dependent mechanism.     

Endogenous glucocorticoids inhibit scratching behavior induced by the administration of compound 48/80 in mice

In this study, we investigated the effects of endogenous glucocorticoids on the compound 48/80 (a condensation product of N-methyl-p-methoxyphenethylamine with formaldehyde)-induced mouse scratching behavior using either RU-486 (mifepristone), a glucocorticoid receptor antagonist, or a surgical resection of the adrenal glands. Subcutaneous injection of compound 48/80 induced not only a corticosterone elevation in the plasma but also an enhanced expression of corticotropin releasing hormone (CRH) mRNA in the paraventricular nucleus, which thus suggests that hypothalamic-pituitary-adrenal axis is activated by the compound 48/80-induced cutaneous reaction. Inhibition of such an endogenous glucocorticoid activity by RU-486 significantly increased the degree of scratching behavior at not only the early-phase (<60 min) but also the late-phase (>60 min) time course after the injection of compound 48/80. Since the elevation of the histamine levels in the plasma in the RU-486-treated mice was no longer found in late-phase scratching behavior, these results thus indicate that histamine is a dominant mediator responsible for early-phase scratching behavior, while different mediators other than histamine may be also involved in the induction of late-phase scratching behavior. Moreover, surgical removal of adrenal glands also significantly increased the compound 48/80-induced scratching behavior without affecting anxiety and locomotor parameters, indicating that endogenous glucocorticoids exert their anti-pururitogenic effects independently of changes in behavioral performance. In conclusion, endogenous glucocorticoid activity was found to suppress the compound 48/80-induced scratching behavior in mice.     

SCH23390, a dopamine D1 receptor antagonist, suppressed scratching behavior induced by compound 48/80 in mice

To clarify the mechanisms by which compound 48/80 (C48/80) induces scratching behavior, the involvement of dopamine D₁ receptors was investigated. The intracisternal (i.t.) administration of SCH23390 (1.0 μg), a selective dopamine D₁ receptor antagonist, significantly decreased C48/80-induced scratching behavior in mice. These results suggest that dopamine D₁ receptors contribute to scratching behavior or the itch sensation induced by subcutaneous injection of C48/80 in mice. Co-administration of SCH23390 and C48/80 enhanced c-fos immunoreactivities in the peduncular part of the lateral hypothalamus (PLH), whereas the immunoreactivities in the other groups were unchanged. The dopaminergic system may be playing an important role in the suppression of C48/80-induced scratching behavior by SCH23390.     

人参皂苷Rg1治疗性给药的抗心肌肥厚作用

目的：观察人参皂苷Rg1治疗性给药对缩窄腹主动脉所致大鼠左心室肥厚的影响。方法：SD大鼠随机分为假手术组、模型组、Rg1（3．75，15mg／kg）组以及左旋精氨酸（L-arg）200mg／kg组。后4组用腹主动脉缩窄术（AAC）造模，手术3周后腹腔注射给药共4周。给药末监测大鼠血流动力学，称心脏质量以计算左室肥厚指标（即左室肥厚指数，LVHI=左室重，体重）和左室重，右室重（LVW／RVW），用实时荧光定量PCR（Real-Time PCR）法检测心房利钠因子（ANF）和钙调神经磷酸酶（CaN）mRNA的表达。结果：与假手术组比较，模型组的血压、左室内收缩压、左室舒张期末压、LVHI和LVW/RVW均显著升高，±dp／dtmax降低，ANF和CaN mRNA表达明显上调。Rg1和L-arg给药不影响血压及左室内收缩压，但显著降低左心室舒张期末压（LVEDP）而增加±dp／dtmax，并使LVHI和LVW／RVW减低，ANF和CaN mRNA表达下调。结论：Rg1具有抗压力超负荷所致左心室肥厚作用，并可能与其抑制CaN信息通路有关。     

Inhibitory effect of ginsenoside Rg5 and its metabolite ginsenoside Rh3 in an oxazolone-induced mouse chronic dermatitis model

The effect of a main constituent ginsenoside Rg5 isolated from red ginseng and its metabolite ginsenoside Rh3 in a chronic dermatitis model was investigated. Ginsenosides Rg5 and Rh3 suppressed swelling of oxazolone-induced mouse ear contact dermatitis. These ginsenosides also reduced mRNA expressions of cyclooxygenase-2, interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma. The inhibition of ginsenoside Rh3 was more potent than that of ginsenoside Rg5. These findings suggest that ginsenoside Rh3 metabolized from ginsenoside Rg5 may improve chronic dermatitis or psoriasis by the regulation of IL-1beta and TNF-alpha produced by macrophage cells and of IFN-gamma produced by Th cells.     

Oral absorption of ginsenoside Rb1 using in vitro and in vivo models

This research attempts to clarify the cause for poor oral absorption of ginsenoside Rb1 (Rb1), one main ingredient of the well known Panax notoginseng saponins (PNS) for curing hemorrhage. Caco-2 cell monolayers were used as an in vitro model to reveal the transport mechanism of Rb1 across the intestinal mucosa. Moreover, the serum concentration-time profiles of Rb1 after tail venous (IV), portal venous (PV), intraduodenal (ID) and peroral (PO) administration to rats were compared to evaluate the first-pass effects of stomach, intestine and liver. In vitro experiments showed that uptake by Caco-2 cell monolayers was temperature dependent, but was not influenced by cyclosporine A and ketoconazole. The change in the apical pH showed no obvious effects on the uptake of Rb1. The uptake and transport were non-saturable, and flux from the apical compartment to the basolateral compartment (A-B) increased linearly with increasing concentration, which indicated a passive transport. Meanwhile, an apparent permeability coefficient of (5.90 +/- 1.02) x 10(-8) cm/s (C0 = 1 mg/mL) predicted an incomplete absorption. The investigation on the pharmacokinetic behavior of Rb1 after different routes of administration to rats showed a significant difference between PO (F(PO) was 0.64%), ID (F(ID) was 2.46%) and PV (F(PV) was 59.49%) administration, and the first-pass effect of the intestine is more significant than that of the stomach and liver in the absorption process. In summary, elimination in the stomach, large intestine and liver contributed to the poor absorption of Rb1, but the low membrane permeability might be a more important factor dominating the extent of absorption.     

HPLC-ELSD法同时测定复方三七漱口液中三七皂苷R_1、人参皂苷Rg_1、Rb_1的含量

目的建立同时测定复方三七漱口液中三七皂苷R1、人参皂苷Rg1和人参皂苷Rb1的HPLCELSD法。方法采用DIKMA Diamonsil C18(2)(250 mm×4.6 mm,5μm)色谱柱,流动相为乙腈-水梯度洗脱,流速1.0 mL/min,柱温30℃,蒸发光散射检测器漂移管温度47℃,载气流速1.5 L/min。结果三七皂苷R1、人参皂苷Rg1和人参皂苷Rb1分别在0.41¹.53、1.551.53、1.55⁵.83、1.585.83、1.58⁵.92μg呈良好线性关系;复方三七漱口液中三七皂苷R1、人参皂苷Rg1和人参皂苷Rb1的平均回收率(n=9)分别为99.31%、100.30%、99.98%,RSD分别为1.60%、0.56%、0.97%。结论该方法简便、准确,专属性、重复性好,可用于复方三七漱口液的质量控制。     

稀有人参皂苷compound K研究进展

人参皂苷compound K是二醇型人参皂苷在人体肠道内的主要代谢产物和最终吸收形式。近年来，由于其各种出色的生物活性和作用，对该化合物的研究越来越受到重视。本文对人参皂苷compound K的制备、生物活性、吸收及代谢等研究进行了详细综述。     

HPLC法同时测定复方黄芪注射液中人参皂苷Re、Rg_1含量

目的建立HPLC法同时测定复方黄芪注射液中人参皂苷Re、Rg1的含量。方法采用HPLC法,色谱柱为DiamonsilTM C18柱(4.6 mm×250 mm,5μm),流动相为乙腈50 mmol.L-1磷酸二氢钾缓冲溶液(体积比为20∶80),柱温为25℃,检测波长为203 nm,流速为1.0 mL.min-1。结果复方黄芪注射液中人参皂苷Re、Rg1与其他成分分离良好。人参皂苷Re的质量浓度在25~500 mg.L-1内(r=0.999 8)、Rg1的质量浓度在25~300 mg.L-1(r=0.999 8)内与峰面积线性关系良好,人参皂苷Re、Rg1的回收率分别为100.2%和99.8%,RSD分别为1.4%和2.0%。结论方法准确、重现性好,可用于复方黄芪注射液的质量控制。     

三七药酒中人参皂苷Rg1、人参皂苷Rb1的含量测定

目的：建立三七药酒中人参皂苷Rg1、人参皂苷Rb1的含量测定方法,为其质量标准提升提供理论基础。方法：采用HPLC梯度洗脱建立三七药酒中人参皂苷Rg1、人参皂苷Rb1的含量测定方法。使用Acchrom Unitary C18色谱柱（4.6 mm×150mm,5μm）,以乙腈（A）-水（B）为流动相,梯度洗脱（0~20 min,20%A;20~45 min,20% A→46% A;45~55min,46% A→55% A;50~60 min,55% A;60~61 min,55% A→90% A;61~70 min,90% A）,流速1.5 mL·min–1,检测波长203 nm,用外标法测定了21个批次的三七药酒中人参皂苷Rg1的含量。结果：人参皂苷Rg1、人参皂苷Rb1分别在3.446~344.6μg·mL–1（r=1.000 0）,6.078~303.9μg·mL–1（r=0.999 9）范围内,线性关系良好,平均加样回收率分别为98.4%（RSD=1.4%,n=6）,95.4%（RSD=2.9%,n=6）。结论：建立的方法简单准确,可用于三七药酒中三七的质量进行控制。     

Pentacyclic triterpenoids, alpha,beta-amyrins, suppress the scratching behavior in a mouse model of pruritus

In the search for natural compounds useful against pruritus, alpha,beta-amyrins, the pentacyclic triterpenes isolated from the resin of popular medicinal plant Protium heptaphyllum were examined on scratching behavior induced by dextran T40 and compound 48/80 in mice. The animals were pretreated orally with alpha,beta-amyrins (50, 100 and 200 mg/kg) or cyproheptadine (10 mg/kg), an antagonist of histamine and serotonin receptors and 2 h later, they were given subcutaneous injections of dextran T40 (75 mg/kg) or compound 48/80 (3 mg/kg) into the rostral back, and scratching was quantified for 20 min. The scratching behavior induced by dextran T40 and compound 48/80 was significantly inhibited in mice pretreated with alpha,beta-amyrins (100 and 200 mg/kg) or cyproheptadine (10 mg/kg), In addition, the compound 48/80-elicited degranulation of rat peritoneal mast cells (ex vivo) was also markedly reduced in animals pretreated with alpha,beta-amyrins (100 mg/kg) or ketotifen (1 mg/kg), a known mast cell stabilizer. In the open-field test, alpha,beta-amyrins (100 and 200 mg/kg)-pretreated mice showed no impairment of spontaneous locomotion, suggesting that these triterpenoids possess no sedative activity that could account for suppression of scratching behavior. These results clearly indicate the antipruritic effect of alpha,beta-amyrins and suggest that this effect may be related to a stabilizing action on mast cell membrane.     

Involvement of unique mechanisms in the induction of scratching behavior in BALB/c mice by compound 48/80

Compound 48/80 induced scratching behavior in BALB/c mice, and the role of mast cell mediators in this behavior was examined. Mouse scratching behavior was detected and evaluated using a new apparatus, MicroAct. Compound 48/80 increased the incidence of scratching behavior and scratching time in a dose-dependent manner, accompanied by a potent activation of mast cells and a potent increase in vascular permeability. Dibucaine and mu-opioid receptor antagonists inhibited the scratching behavior. Although histamine H(1) receptor antagonists potently inhibited the vascular permeability increase, they did not affect the scratching behavior. Methysergide inhibited the scratching behavior slightly without affecting the vascular permeability increase, whereas cyproheptadine inhibited both. A cyclooxygenase inhibitor, a 5-lipoxygenase-activating protein inhibitor and a PAF receptor antagonist did not affect the scratching behavior. High doses of serotonin induced scratching behavior less frequently than did compound 48/80. Furthermore, mast cell-deficient WBB6F1-W/W(v) mice exhibited frequent scratching behavior after injection of compound 48/80. These results clearly indicate that compound 48/80 can induce scratching behavior in mice independent of mast cell mediators.     

RP-HPLC法同时测定优可力片中人参皂苷Rg_1、Re和Rb_1的含量

目的测定优可力片中人参皂苷Rg1、Re和Rb1含量的方法。方法采用反相高效液相色谱法。色谱柱:Kromasil C18(250 mm×4.6 mm,5μm),流动相:乙腈-体积分数为0.1%的磷酸水溶液(梯度洗脱),流速:1.0 mL.min-1,检测波长:203 nm,柱温:30℃,进样量:10μL。结果人参皂苷Rg1、Re及Rb1的检测质量浓度分别在14.1～282.0(r=0.999 6)、22.0～440.0(r=0.999 9)、10.2～204.0 mg.L-1(r=0.999 9)内与各自峰面积呈良好线性关系;三者的平均回收率分别为98.3%、99.7%和98.7%,RSD(%,n=9)分别为1.0、0.9和1.6。结论该方法可用于优可力片的质量控制。     

Difference in oral absorption of ginsenoside Rg1 between in vitro and in vivo models

AIM: To clarify the cause of poor oral absorption of ginsenoside Rg1 (Rg1), the active ingredient in Panax notoginseng saponins (PNS) used for treating hemorrhage. METHODS: Caco-2 cell monolayers were used as an in vitro model to study the transport mechanism of Rg1 across the intestinal mucosa. Moreover, the serum concentration-time profiles after peroral (po), intraduodenal (id), portal venous (pv) and tail venous (iv) administration of Rg1 in rats were compared to evaluate the first-pass effects in the stomach, intestine, and liver. RESULTS: Uptake of Rg1 by Caco-2 cell monolayers was temperature-dependent, but was not influenced by cyclosporin A. The change in the apical pH produced no obvious effect on the uptake of Rg1. The uptake and transport of Rg1 was non-saturable; whereas the flux from the apical compartment to the basolateral compartment (A-B) increased in a linear manner with the increase in concentration, indicating passive transport. An apparent permeability coefficient of (2.59+/-0.17)*10(-7) cm/s (C0=1 mg/mL) predicted incomplete absorption. A significant difference was observed between the po (F(po) was 3.29% at a dose of 1500 mg/kg), id (F(id) was 6.60% at a dose of 1200 mg/kg) and pv (F(pv) was 50.56%) administration methods, and the barrier function of the intestine was more significant than those of the stomach and liver in the absorption process. CONCLUSION: Elimination in the stomach, large intestine and liver contributed to the low oral bioavailability of Rg1, but low membrane permeability might be a more important factor in determining the extent of absorption.