Anti-hepatocarcinoma effect of cordycepin against NDEA-induced hepatocellular carcinomas via the PI3K/Akt/mTOR and Nrf2/HO-1/NF-κB pathway in mice

The purpose of the present study was to evaluate the effects of cordycepin (CA) on N-nitrosodiethylamine (NDEA)-induced hepatocellular carcinomas (HCC) and explore its potential mechanisms. Mice were randomly assigned to four groups: control group, NDEA group, NDEA+CA (20mg/kg) group, NDEA+CA (40mg/kg) group. The animal of each group were given NDEA (100ppm) in drinking water. One hour later, CA, which was dissolved in PBS, were intragastrically administered for continuous seven days. The results showed that CA reduced the activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in liver and serum. CA also reduced the levels of interleukin-6 (IL-6), IL-1β, tumor necrosis factor-α (TNF-α), methane dicarboxylic aldehyde (MDA), and stored the activity of superoxygen dehydrogenises (SOD) in serum. CA could obviously attenuate the hepatic pathological alteration. Furthermore, CA effectively inhibited the phosphorylations of phosphatidylinositol 3 kinase(PI3K), protein kinase B (Akt), mammalian target of rapamycin (mTOR). In conclusion, our research suggested that CA exhibited protective effects on NDEA-induced hepatocellular carcinomas via the PI3K/Akt/mTOR pathway.

Biosynthetic Pathway Analysis for Improving the Cordycepin and Cordycepic Acid Production in Hirsutella sinensis

Hirsutella sinensis is considered as the only correct anamorph of Ophiocordyceps sinensis. To improve cordycepin and cordycepic acid production in H. sinensis, the biosynthetic pathways of cordycepin and cordycepic acid were predicted, and verified by cloning and expressing genes involved in these pathways, respectively. Then, 5'-nucleotidase participating in biosynthetic pathway of cordycepin, hexokinase, and glucose phosphate isomerase involved in biosynthetic pathway of cordycepic acid, were demonstrated playing important roles in the corresponding biosynthetic pathway by real-time PCR, accompanying with significantly up-regulated 15.03-, 5.27-, and 3.94-fold, respectively. Moreover, the metabolic regulation of H. sinensis was performed. As expected, cordycepin production reached 1.09 mg/g when additional substrate of 5'-nucleotidase was 4 mg/mL, resulting in an increase of 201.1 % compared with the control. In the same way, cordycepic acid production reached 26.6 and 23.4 % by adding substrate of hexokinase or glucose phosphate isomerase, leading to a rise of 77.3 and 55.1 %, respectively. To date, this is the first time to improve cordycepin and cordycepic acid production through metabolic regulation based on biosynthetic pathway analysis, and metabolic regulation is proved as a simple and effective way to enhance the output of cordycepin and cordycepic acid in submerged cultivation of H. sinensis.