Effects of ginsenosides injected intrathecally or intracerebroventricularly on antinociception induced by morphine administrated intracerebroventricularly in the mouse

Pesticide multiresidue analysis in Panax ginseng (C. A. Meyer) by solid-phase extraction and gas chromatography with electron capture and nitrogen-phosphorus detection

An analytical multi-residue method using gas chromatography coupled with electron capture and a nitrogen-phosphorus detector was investigated for the simultaneous determination of 18 commonly used insecticides and fungicides in Korean ginseng (Panax ginseng C. A. Meyer). Samples were previously extracted with an acetonitrile and cleaned up by solid-phase extraction (SPE). The calibration curves were linear, with determination coefficients higher than 0.989. Recoveries at concentrations between 0.01 and 14.9 ppm ranged from 72.3 to 117.2%, with precision, which was expressed as relative standard deviation (RSD), at values lower than 5%. The proposed method was applied to the determination of pesticide levels from 12 ginseng samples, taken from four different agricultural areas of Jeonnam province, where several insecticides and fungicides were applied. Except in one sample, tolclofos-m was the only pesticide contained at a level lower than the maximum residue limits (MRL) authorized by the Korea Food and Drug Administration (KFDA) in real ginseng samples grown for 4, 5 and 6 years.

Protective role ofPanax ginseng extract standardized with ginsenoside Rg3 against acrylamide-induced neurotoxicity in rats

Acrylamide (ACR) is an industrial neurotoxic chemical that has been recently found in carbohydrate-rich foods cooked at high temperatures. ACR was designated as a probable human carcinogen by IARC (1994) and USEPA (1988). Panax ginseng extract has efficacies such as anticancer, antihypertension, antidiabetes and antinociception. The objective of the current study is to evaluate the protective effects of Panax ginseng extract against ACR-induced toxicity in rats. Sixty adult Sprague Dawley female rats were divided into six groups included a control group, a group treated orally with ACR (50 mg kg(-1) body weight; b.w.) for 11 days, a group treated orally with Panax ginseng extract (20 mg kg(-1) b.w.) for 11 days and groups treated orally with Panax ginseng for 11 days before, during or after 11 days of ACR treatment. The results indicated that treatment with ACR alone resulted in a significant increase in lipid peroxidation level and LDH activity in brain homogenate as well as in serum CK activity, whereas it caused a significant decrease in SOD activity and a small but statistically insignificant decrease in Na(+)K(+)-ATPase activity in brain homogenate. Serum serotonin, corticosterone, T3, T4, TSH, estradiol, progesterone and plasma adrenaline were significantly decreased in ACR-treated rats. Treatment with Panax ginseng before, during or after ACR treatment reduced or partially antagonized the effects induced by ACR towards the normal values of controls. It could be concluded that Panax ginseng extract exhibited a protective action against ACR toxicity and it is worth noting that treatment with Panax ginseng extract before or at the same time as ACR treatment was more effective than when administered after ACR treatment.

Pharmacological action of Panax ginseng on the behavioral toxicities induced by psychotropic agents

Morphine-induced analgesia has been shown to be antagonized by ginseng total saponins (GTS), which also inhibit the development of analgesic tolerance to and physical dependence on morphine. GTS is involved in both of these processes by inhibiting morphine-6-dehydrogenase, which catalyzes the synthesis of morphinone from morphine, and by increasing the level of hepatic glutathione, which participates in the toxicity response. Thus, the dual actions of ginseng are associated with the detoxification of morphine. In addition, the inhibitory or facilitated effects of GTS on electrically evoked contractions in guinea pig ileum (mu-receptors) and mouse vas deferens (delta-receptors) are not mediated through opioid receptors, suggesting the involvement of non-opioid mechanisms. GTS also attenuates hyperactivity, reverse tolerance (behavioral sensitization), and conditioned place preference induced by psychotropic agents, such as methamphetamine, cocaine, and morphine. These effects of GTS may be attributed to complex pharmacological actions between dopamine receptors and a serotonergic/adenosine A2A/ delta-opioid receptor complex. Ginsenosides also attenuate the morphine-induced cAMP signaling pathway. Together, the results suggest that GTS may be useful in the prevention and therapy of the behavioral side effects induced by psychotropic agents.

The effect of Korean red ginseng on liver regeneration after 70% hepatectomy in rats

The effect of Korean red ginseng (KRG) on morphologic change and function of the liver was investigated after 70% hepatectomy in rats. The liver weight and hepatocyte proliferation of the KRG treated groups significantly increased compared to those of the control group. KRG inhibited the increase of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, and the number and area of lipid droplets. On the basis of these results, it could be concluded that KRG accelerated the liver regeneration and ameliorated liver injury after hepatectomy in rats.

Effect of ginsenosides administered intrathecally on the antinociception induced by cold water swimming stress in the mouse

We examined the effects of ginseng total saponin (GTS) and several ginsenosides injected intrathecally (i.t.) or intracerebroventricularly (i.c.v.) on the antinociception induced by cold water swimming. The tail-flick response was used as an antinociceptive parameter. We found that i.t. injection of GTS time- and dose-dependently attenuated inhibition of the tail-flick response induced by cold water swimming, although GTS given i.c.v. had no significant effect on the latency of the tail-flick response induced by cold water swimming. To identify those responsible for antagonism of GTS against cold water swimming-induced antinociception, the effects of various kinds of ginsenosides (R(b1), R(b2), R(c), R(d), R(e), and R(g1)) on inhibition of the tail-flick response induced by cold water swimming were examined. R(b1), R(d), R(e), and R(g1) effectively attenuated the inhibition of the tail-flick response induced by cold water swimming stress. Our results suggest that GTS injected spinally, but not supraspinally, reduces the antinociception induced by this stress, and that the responsible ginsenosides against antinociception induced by cold water swimming may be R(b1), R(d), R(e), and R(g1). Moreover, the possible involvement of the opioid system in the regulation of cold water swimming stress-induced antinociception by these four ginsenosides is discussed.

Ginsenoside Rf potentiates U-50,488H-induced analgesia and inhibits tolerance to its analgesia in mice

In the present study, the effect of ginsenoside Rf (Rf), a trace component of Panax ginseng on U-50,488H (U50), a selective kappa opioid-induced analgesia and its tolerance to analgesia was studied using the mice tail-flick test. In addition, the possible mechanism by which Rf may affect U50-induced analgesia was investigated. Intraperitoneal administration of U50 (40 mg/kg) produced analgesia. Rf (10(-14)-10(-10) mg/kg) on co treatment dose-dependently potentiated the U50 (40 mg/kg)-induced analgesia. Rf (10(-12)-10(-2) mg/ml) did not alter the binding of [3H] naloxone, a opioid ligand and [3H]PN200-110, a dihydropyridine ligand to mice whole brain membrane. Twice daily administration of U50 (40 mg/kg) for six days induced tolerance to its analgesia. Chronic treatment (day 4-day 6) of Rf (10(-14)-10(-10) mg/kg) to U50-tolerant mice, dose-dependently inhibited the tolerance. The inhibition of tolerance to U50-induced analgesia by Rf was not altered by flumazenil (0.1 mg/kg), a benzodiazepine receptor antagonist and picrotoxin (1 mg/kg), a GABA(A)-gated chloride channel blocker on chronic treatment. In conclusion, these findings for the first time demonstrated that ginsenoside Rf potentiates U50-induced analgesia, inhibits tolerance to its analgesia, and suggests that Rf affects U50-induced analgesia via non-opioid, non-dihydropyridine-sensitive Ca(+2) and non-benzodiazepine-GABA(A)ergic mechanisms in mice.

Panax ginseng blocks morphine-induced thymic apoptosis by lowering plasma corticosterone level

The effects of Panax ginseng on morphine-induced immune suppression were studied. Morphine (20 mg/kg, SC, 4 days) decreased body weight increment rate and caused atrophy of thymus and spleen. These changes were partly reversed by concomitant administration of ginseng total saponin (GTS, 100 mg/kg, oral, 9 days). Morphine elevated the serum corticosterone level and caused the DNA fragmentation of thymocytes. These sequential events were completely blocked by a concomitant administration of GTS. Flow cytometry analysis showed that GTS specifically blocked morphine-induced apoptosis of thymocytes.