||Ginsenoside Rf is a trace component of ginseng root, which has antinociception, analgesia, anti-inflammatory, and anti-cancer activities, it induces G2/Mphase cell cycle arrest and apoptosis in human osteosarcoma MG-63 cells through the mitochondrial pathway. Rf can act through a novel G protein-linked receptor in the nervous system by inhibiting N-type Ca2+ channel. Rf significantly reduces the production of IL-1β, IL-6, TNF-α, NO, and ROS, and suppresses TNF-α/LPS-induced NF-κB transcriptional activity.|
||Bcl-2/Bax | CDK | Caspase | TNF-α | NO | ROS | IL Receptor | NF-kB | P450 (e.g. CYP17) | GABA Receptor | Calcium Channel|
|Oncol Rep. 2014 Jan;31(1):305-13. |
|Induction of G2/M phase cell cycle arrest and apoptosis by ginsenoside Rf in human osteosarcoma MG‑63 cells through the mitochondrial pathway.[Pubmed: 24173574]|
|Ginsenosides, extracted from the traditional Chinese herb ginseng, are a series of novel natural anticancer products known for their favorable safety and efficacy proﬁles.
The present study aimed to investigate the cytotoxicity of Ginsenoside Rf to human osteosarcoma cells and to explore the anticancer molecular mechanisms of Ginsenoside Rf.
METHODS AND RESULTS:
Five human osteosarcoma cell lines (MG-63, OS732, U-2OS, HOS and SAOS-2) were employed to investigate the cytotoxicity of Ginsenoside Rf by MTT and colony forming assays. After treatment with Ginsenoside Rf, MG-63 cells which were the most sensitive to Ginsenoside Rf, were subjected to flow cytometry to detect cell cycle distribution and apoptosis, and nuclear morphological changes were visualized by Hoechst 33258 staining. Caspase-3, -8 and -9 activities were also evaluated. The expression of cell cycle markers including cyclin B1 and Cdk1 was detected by RT-PCR and western blotting. The expression of apoptotic genes Bcl-2 and Bax and the release of cytochrome c were also examined by western blotting. Change in the mitochondrial membrane potential was observed by JC-1 staining in situ. Our results demonstrated that the cytotoxicity of Ginsenoside Rf to these human osteosarcoma cell lines was dose-dependent, and the MG-63 cells were the most sensitive to exposure to Ginsenoside Rf. Additionally, Ginsenoside Rf induced G2/M phase cell cycle arrest and apoptosis in MG-63 cells. Furthermore, we observed upregulation of Bax and downregulation of Bcl-2, Cdk1 and cyclin B1, the activation of caspase-3 and -9 and the release of cytochrome c in MG-63 cells following treatment with Ginsenoside Rf.
Our findings demonstrated that Ginsenoside Rf induces G2/M phase cell cycle arrest and apoptosis in human osteosarcoma MG-63 cells through the mitochondrial pathway, suggesting that Ginsenoside Rf, as an effective natural product, may have a therapeutic effect on human osteosarcoma.
|Mol Pharmacol. 2002 Apr;61(4):928-35. |
|Functional expression of a novel ginsenoside Rf binding protein from rat brain mRNA in Xenopus laevis oocytes.[Pubmed: 11901233]|
|We have shown that Ginsenoside Rf (Rf) regulates voltage-dependent Ca(2+) channels through pertussis toxin (PTX)-sensitive G proteins in rat sensory neurons.
METHODS AND RESULTS:
These results suggest that Rf can act through a novel G protein-linked receptor in the nervous system. In the present study, we further examined the effect of Rf on G protein-coupled inwardly rectifying K(+) (GIRK) channels after coexpression with size-fractionated rat brain mRNA and GIRK1 and GIRK4 (GIRK1/4) channel cRNAs in Xenopus laevis oocytes using two-electrode voltage-clamp techniques. We found that Rf activated GIRK channel in a dose-dependent and reversible manner after coexpression with subfractions of rat brain mRNA and GIRK1/4 channel cRNAs. This Rf-evoked current was blocked by Ba(2+), a potassium channel blocker. The size of rat brain mRNA responding to Rf was about 6 to 7 kilobases. However, Rf did not evoke GIRK current after injection with this subfraction of rat brain mRNA or GIRK1/4 channel cRNAs alone. Other ginsenosides, such as Rb(1) and Rg(1), evoked only slight induction of GIRK currents after coexpression with the subfraction of rat brain mRNA and GIRK1/4 channel cRNAs. Acetylcholine and serotonin almost did not induce GIRK currents after coexpression with the subfraction of rat brain mRNA and GIRK1/4 channel cRNAs. Rf-evoked GIRK currents were not altered by PTX pretreatment but were suppressed by intracellularly injected guanosine-5'-(2-O-thio) diphosphate, a nonhydrolyzable GDP analog.
These results indicate that Rf activates GIRK channel through an unidentified G protein-coupled receptor in rat brain and that this receptor can be cloned by the expression method demonstrated here.
|Life Sci. 2003 Jan 3;72(7):759-68. |
|Ginsenoside Rf potentiates U-50,488H-induced analgesia and inhibits tolerance to its analgesia in mice.[Pubmed: 12479975]|
|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.
METHODS AND RESULTS:
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.