The role of Cydonia oblonga, Portulaca oleracea, and Artemisia dracunculus on hypoxia

Hypoxia exists in some malignancies and is a prognostic risk factor contributing to tumor growth and metastasis. Anti-hypoxic compounds may improve this situation and be considered anti-cancer agents. In previous reports, Cydonia oblonga, Portulaca oleracea, and Artemisia dracunculus showed anti-cancer activity. So, we investigated the anti-hypoxic activities of C. oblonga, P. oleracea, and A. dracunculus to evaluate the possible mechanism of the plant's effectiveness in treating cancer.

Total phenolic and flavonoid contents and HPLC analysis were performed on C. oblonga leaves, P. oleracea, and A. dracunculus aerial parts extract. Anti-hypoxic activities were evaluated in asphyctic, haemic, and circulatory hypoxia models.

A. dracunculus extract (at 250 mg/kg) significantly improved the survival time compared to the normal saline (P < 0.0001) in asphyctic hypoxia, even its effect was significantly better than phenytoin in this dose (P = 0.0005). Although the extracts increased the survival time in other doses, their effects were not significant (P > 0.05). In haemic hypoxia, the extracts were ineffective at any dose (P > 0.05). At 250 mg/kg, P. oleracea and A. dracunculus significantly increased the survival time (P < 0.001 and P < 0.05, respectively) in circulatory hypoxia. Their effects were similar to propranolol (P > 0.05).

The anti-cancer effects of C. oblonga are not dependent on the anti-hypoxic effects. P. oleracea and A. dracunculus have anti-hypoxic effects only in high doses, indicating their extracts' weak anti-hypoxic ability or the presence of potent anti-hypoxic compounds with low concentrations in them.