Sann-Joong-Kuey-Jian-Tang induces autophagy in HepG2 cells via regulation of the phosphoinositide-3 kinase/Akt/mammalian target of rapamycin and p38 mitogen-activated protein kinase pathways.

Abstract

Sann-Joong-Kuey-Jian-Tang (SJKJT), a traditional Chinese medicine, was previously reported to induce autophagy and inhibit the proliferation of the human HepG2 hepatocellular carcinoma cell line via an extrinsic pathway. In the present study, the effects of SJKJT-induced autophagy and the cytotoxic mechanisms mediating these effects were investigated in HepG2 cells. The cytotoxicity of SJKJT in the HepG2 cells was evaluated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The results demonstrated that the half-maximal inhibitory concentration of SJKJT was 2.91 mg/ml at 24 h, 1.64 mg/ml at 48 h and 1.26 mg/ml at 72 h. The results of confocal fluorescence microscopy indicated that SJKJT resulted in the accumulation of green fluorescent protein-LC3 and vacuolation of the cytoplasm. Flow cytometric analysis revealed the accumulation of acidic vesicular organelles. Furthermore, western blot analysis, used to determine the expression levels of autophagy-associated proteins, demonstrated that the HepG2 cells treated with SJKJT exhibited LC3B-I/LC3B-II conversion, increased expression levels of Beclin, Atg-3 and Atg-5 and reduced expression levels of p62 and decreased signaling of the phosphoinositide-3 kinase/Akt/mammalian target of rapamycin and the p38 mitogen-activated protein kinase pathways. Taken together, these findings may assist in the development of novel chemotherapeutic agents for the treatment of malignant types of liver cancer.

• Authors: Wan-Ling Chuang, Chin-Cheng Su, Ping-Yi Lin, Chi-Chen Lin, Yao-Li Chen
• Journal: Molecular medicine reports (Mol Med Rep) Vol. 12 Issue 2 Pg. 1677-84 (Aug 2015) ISSN: 1791-3004 [Electronic] Greece
• PMID: 25847489 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• ATG5 protein, human
• Antineoplastic Agents
• Apoptosis Regulatory Proteins
• Autophagy-Related Protein 5
• Autophagy-Related Proteins
• BECN1 protein, human
• Beclin-1
• Drugs, Chinese Herbal
• MAP1LC3A protein, human
• Membrane Proteins
• Microtubule-Associated Proteins
• sann-joong-kuey-jian-tang
• Ubiquitin-Conjugating Enzymes
• Proto-Oncogene Proteins c-akt
• TOR Serine-Threonine Kinases
• p38 Mitogen-Activated Protein Kinases
• ATG3 protein, human

Topics

• Antineoplastic Agents (pharmacology)
• Apoptosis Regulatory Proteins (metabolism)
• Autophagy (drug effects)
• Autophagy-Related Protein 5
• Autophagy-Related Proteins
• Beclin-1
• Cell Survival (drug effects)
• Down-Regulation (drug effects)
• Drugs, Chinese Herbal (pharmacology)
• Hep G2 Cells
• Humans
• Membrane Proteins (metabolism)
• Microscopy, Confocal
• Microtubule-Associated Proteins (metabolism)
• Phosphatidylinositol 3-Kinases (metabolism)
• Proto-Oncogene Proteins c-akt (metabolism)
• Signal Transduction (drug effects)
• TOR Serine-Threonine Kinases (metabolism)
• Ubiquitin-Conjugating Enzymes (metabolism)
• Up-Regulation (drug effects)
• p38 Mitogen-Activated Protein Kinases (metabolism)