Combined effects of ginseng and radiotherapy on experimental liver cancer

Effect of therapies-mediated modulation of telomere and/or telomerase on cancer cells radiosensitivity

Cancer is one of the leading causes of death in the world. Many strategies of cancer treatment such as radiotherapy which plays a key role in cancer treatment are developed and used nowadays. However, the side effects post-cancer radiotherapy and cancer radioresistance are two major causes of the limitation of cancer radiotherapy effectiveness in the cancer patients. Moreover, reduction of the limitation of cancer radiotherapy effectiveness by reducing the side effects post-cancer radiotherapy and cancer radioresistance is the aim of several radiotherapy-oncologic teams. Otherwise, Telomere and telomerase are two cells components which play an important role in cancer initiation, cancer progression and cancer therapy resistance such as radiotherapy resistance. For resolving the problems of the limitation of cancer radiotherapy effectiveness especially the cancer radio-resistance problems, the radio-gene-therapy strategy which is the use of gene-therapy via modulation of gene expression combined with radiotherapy was developed and used as a new strategy to treat the patients with cancer. In this review, we summarized the information concerning the implication of telomere and telomerase modulation in cancer radiosensitivity.

Panax ginseng Meyer prevents radiation-induced liver injury via modulation of oxidative stress and apoptosis

BACKGROUND

Radiotherapy is one of the most important modalities in cancer treatment; however, normal tissue damage is a serious concern. Drug development for the protection or reduction of normal tissue damage is therefore a clinical issue. Herein, we evaluated the protective properties of Panax ginseng Meyer and its corresponding mechanisms.

METHODS

C56BL/6 mice were orally pretreated with P. ginseng water extract (PGE; 25 mg/kg, 50 mg/kg, or 100 mg/kg) or intraperitoneally injected melatonin (20 mg/kg) for 4 d consecutively, then exposed to 15-Gy X-ray radiation 1 h after the last administration. After 10 d of irradiation, the biological properties of hematoxicity, fat accumulation, histopathology, oxidative stress, antioxidant activity, pro-inflammatory cytokines, and apoptosis signals were examined in the hepatic tissue.

RESULTS

The irradiation markedly induced myelosuppression as determined by hematological analysis of the peripheral blood. Steatohepatitis was induced by X-ray irradiations, whereas pretreatment with PGE significantly attenuated it. Oxidative stress was drastically increased, whereas antioxidant components were depleted by irradiation. Irradiation also notably increased serum liver enzymes and hepatic protein levels of pro-inflammatory cytokines. Those alterations were markedly normalized by pretreatment with PGE. The degree of irradiation-induced hepatic tissue apoptosis was also attenuated by pretreatment with PGE, which was evidenced by a terminal deoxynucleotidyl transferase 2'-deoxyuridine 5'-triphosphate nick-end labeling assay, western blotting, and gene expressions analysis, particularly of apoptotic molecules.

CONCLUSION

We suggest that PGE could be applicable for use against radiation-induced liver injury, and its corresponding mechanisms involve the modulation of oxidative stress, inflammatory reactions, and apoptosis.

Isolation and characterization of a group of oligopeptides related to oxidized glutathione from the root of Panax ginseng

Six gamma-glutamyl oligopeptides were isolated for the first time from aqueous methanol extracts of Panax ginseng root by using column chromatography on ion-exchange resin, gel filtration and reverse-phase high-performance liquid chromatography. Their structures had been established with the methods of amino acid analysis, N-terminal, C-terminal determination and double-coupling sequence analysis. They were: P-I (N-gamma-glutamylcystinyl-bis-glycine), P-ll (gamma-glutamylcysteinylglycine disulfide, oxidized glutathione), P-III (N,N'-bis-gamma-glutamylcystinylglycine), P-IV (gamma-glutamylcysteinylglycinamide disulfide), P-V (N-gamma-glutamylglycylcysteine disulfide), P-VI(gammaglutamylarginine); five of them are related to oxidized glutathione. The structures were further confirmed by the chemical synthesis. As far as we know, P-V (N-gamma-glutamylglycylcysteine disulfide) is a new biologically active peptide which exhibits somnogenic effect and is more potent than that of P-II.

Recovery of the hematopoietic system by Si-Jun-Zi-Tang in whole body irradiated mice

The herbal formulation Si-Jun-Zi-Tang reduced the decrease of leukocytes, erythrocytes, thrombocytes and hematocrit in irradiated mice. In general, its protection was more effective in leukocytes and thrombocytes than other hematocytes. Protection of bone marrow stem cells by Si-Jun-Zi-Tang was markedly enhanced by increased radiotolerance under the dose ranging from 0 to 5 Gy. This increased radiotolerance led to a prolonged shoulder in the survival curve but did not influence the D0 value. Si-Jun-Zi-Tang exerted a beneficial effect on clinical syndromes such as anemia. From the results in this study, we concluded preliminarily that the most effective concentration with least toxicity was about 20 mg/20 g body weight. At this dose, levels of leukocytes as well as thrombocytes were enhanced significantly after chi-irradiation. Elevation of erythrocytes and hematocrits could also be found but was not significant.