A novel polysaccharide from the Sarcodon aspratus triggers apoptosis in Hela cells via induction of mitochondrial dysfunction.

Background: Polysaccharides extracted from fungus that have been used widely in the food and drugs industries due to biological activities.

Objective: The objective of the present study was to investigate the tumor-suppressive activity and mechanism of a novel polysaccharide (SAP) extracted from Sarcodon aspratus .

Methods: The SAP was extracted and purified using Sepharose CL-4B gel from S. aspratus . The cytotoxicity of SAP on cell lines was determined by MTT method. Cellular migration assays were implemented by using transwell plates. The apoptosis and mitochondrial membrane potential (Δψm) of Hela cells were analyzed by flow cytometry. The western blot was used to determine the protein expression of Hela cells.

Results: The results showed that SAP with a molecular weight of 9.01×105 Da could significantly inhibit the growth of Hela cells in vitro . Three-dimensional cell culture (3D) and transwell assays showed that SAP restrained the multi-cellular spheroids growth and cell migration. Flow cytometry analysis revealed that SAP induced a loss of mitochondrial membrane potential (Δψm). Western blot assays indicated that SAP promoted the release of cytochrome c, increased Bax expression, down-regulated of Bcl-2 expression and activated of caspase-3 expression.

Conclusion: This study suggested that SAP induced Hela cells apoptosis via mitochondrial dysfunction that are critical in events of caspase apoptotic pathways. The anti-tumor (Hela cells) activity of SAP recommended that S. aspratus could be used as a powerful medicinal mushroom against cancer.