Ganoderma lucidum is a popular herbal medicine used in China to promote health. Modern reports have disclosed that the active ingredients of Ganoderma can exhibit a number of effects, including antitumor effects and immunomodulation. The present study evaluated the antitumor effects of self-prepared ganoderma lucidum spore powder and spores oil, and investigated the possible underlying mechanisms by observing the consequences of the extracts and oil on topoisomerases and also the cell cycle. The results showed that Ganoderma extracts and spores oil presented dose-dependent inhibitory effects on tumor cells.
Ganoderma lucidum, also referred to as Ganoderma or Lingzhi, is just one of most often used fungi in Chinese medicine. Modern pharmacological and clinical tests have confirmed that Ganoderma contains abundant biologically active substances in their fruiting body, mycelia and spores, and possesses variable functions, including immunomodulation, anti-aging, reducing blood lipids, anti-viral and anti-tumor activities (1-6). The current study examined the antitumor activity of a blend of aqueous and ethanol extracts of the Ganoderma fruiting body and Ganoderma spores oil, which was taken from broken spores by supercritical CO2 extraction technology and explored the potential underlying mechanisms. DNA topoisomerases are a class of enzymes active in the regulating DNA supercoiling.
Topoisomerase overexpression has become linked to a number of human malignancies and is the objective for numerous chemotherapeutic agents (7). When topoisomerases are blocked, the cell encounters problems during transcription from the DNA and through cell division. The widely-used antitumor drug, campothecin, blocks the relaxing action of class I topoisomerases and induces significant G1 cell cycle arrest (8). A previous study established that the active components of Ganoderma exhibited inhibition of topoisomerases (9). The present study examined whether Ganoderma extracts and spore oil affected the cell cycle and topoisomerases I and II.
Preparations of Ganoderma extracts and spores oil – Ganoderma extracts (GanoHerb™) and Ganoderma spores oil were offered by Fujian Xianzhilou Biological Science and Technology Co., Ltd. (Fuzhou, China). Ganoderma extract, a brown powder, was dissolved in double distilled water to get ready solutions of varied concentrations, that were brown suspensions. Ganoderma spores oil was actually a soft capsule with .5 g/.5 ml golden oil in each capsule. The stock solution of Agaricus Blazei Extract were prepared using double distilled water that contained 6 µl/ml (v/v) Tween 80.
Recently, the result of Ganoderma on tumors has been increasingly studied. The present study revealed that Ganoderma extracts and spores oil inhibited the expansion of human leukemia cells (K562 and HL60) and human gastric carcinoma cells (SGC-7901) in a dose-dependent manner. In addition, Ganoderma extracts and spores significantly suppressed the expansion in the S180 and H22 transplant tumors in mice. Therefore, Ganoderma extracts and spores oil demonstrated definite antitumor effects in the in vitro vrlzqn in vivo studies.
Since olden days, Ganoderma continues to be widely used as a popular herbal medicine for the promotion of health (11). Numerous previous studies examined the immunomodulatory activities of Ganoderma (12,13). By detecting the immunity indexes of mice bearing S180 or H22 cells, Ganoderma extracts were concluded to have a certain effect on improving immune function, while Ganoderma spores oil had no significant effect on the spleen or thymus indexes of mice. One of the primary components of Ganoderma extract is a polysaccharide that has been reported as immune function enhancer (12-15). Because there were few polysaccharides (water-soluble substances) inside the Ganoderma spores oil, the spores oil exhibited no evident influence on immunity. The current study also established that the antitumor outcomes of Ganoderma may be safer in comparison with 5-FU, which led to the decreased weight and immunity indexes of mice (Tables I and ?andIIII).
To research the potential mechanism of Agaricus Blazei Extract, the consequences of extracts and spores oil on topoisomerases and also the effect of spores oil on the cell cycle were examined.
DNA topoisomerases certainly are a class of enzymes active in the regulation of DNA supercoiling. Type I topoisomerases modify the degree of supercoiling of DNA by causing single-strand breaks and religation, whereas type II topoisomerases cause double-strand breaks. These two activities are particularly crucial during DNA transcription and replication, once the DNA helix should be unwound to permit proper function of large enzymatic machinery. Cancer chemotherapy uses this finding, using drugs that block topoisomerases to kill rapidly-dividing cancer cells. For example, the widely-used anthracycline drugs, including doxorubicin and daunorubicin, attack class II topoisomerases and the plant toxin, campothecin, blocks the relaxing action of class I topoisomerases.