ALA-PDT suppressed the cell growth by Akt-/Erk-mTOR-p70 s6k pathway in human SZ95 sebocytes in vitro.

Abstract

BACKGROUND:

Topical 5-aminolevulinic acid mediated photodynamic therapy (PDT) is known to be an effective method in treating acne vulgaris and other sebaceous gland-related diseases. The therapeutic mechanisms of ALA-PDT still remain undetermined. Our team has reported that ALA-PDT suppressed the cell growth in SZ95 sebocytes by mTOR-p70 S6K signaling. In this study, we aimed to investigate upstream of the mammalian target of rapamycin (mTOR) signaling cascade after ALA-PDT on cell growth of human SZ95 sebocytes.

MATERIAL AND METHODS:

Human SZ95 sebocytes were treated with different concentration of 5-ALA PDT. Western blotting was used to detect and analyze the protein expression level of P-Akt (T308)/Akt, P-Akt (S473)/Akt, P-Erk/Erk, P-AMPKα (T172)/AMPK, P-AMPKα1 (S485)/AMPKα2 (S491)/AMPK, P-PRAS40/PRAS40, RagC. Meanwhile, mTOR pathway activator IGF-1 and mTORC1 inhibitor rapamycin were added to observe the interferences of P-p70 S6K/p70 S6K after ALA-PDT.

RESULTS:

mTOR pathway inhibitor rapamycin decreased the level of P-p70 S6K reduced by ALA-PDT. Conversely, mTOR pathway activator IGF-1. ALA-PDT reduced the level of P-Akt (T308), P-Erk, P-AMPKα (T172), P-AMPKα1 (S485)/AMPKα2 (S491) and P-PRAS40, and no change was observed in the level of Rag C.

CONCLUSION:

ALA-PDT suppresses the cell growth in SZ95 cells through Akt-/Erk- mTOR -p70 s6k pathway rather than PRAS40-/RagC- mTOR pathway.

• Authors: Wenjie Liu, Qianqian Wang, Jiang Tuo, Yufeng Chang, Jiayi Ying, Min Jiang, Christos C Zouboulis, Leihong Xiang
• Journal: Photodiagnosis and photodynamic therapy (Photodiagnosis Photodyn Ther) Vol. 24 Pg. 1-6 (Dec 2018) ISSN: 1873-1597 [Electronic] Netherlands
• PMID: 29964224 (Publication Type: Journal Article)
• Copyright: Copyright © 2018 Elsevier B.V. All rights reserved.

Chemical References

• DNA-Binding Proteins
• Photosensitizing Agents
• Aminolevulinic Acid
• Ribosomal Protein S6 Kinases, 70-kDa
• TOR Serine-Threonine Kinases
• p38 Mitogen-Activated Protein Kinases
• AMP-Activated Protein Kinases
• Sirolimus

Topics

• AMP-Activated Protein Kinases (metabolism)
• Aminolevulinic Acid (pharmacology)
• Cell Enlargement (drug effects)
• Cell Line
• DNA-Binding Proteins
• Dose-Response Relationship, Drug
• Humans
• Photochemotherapy (methods)
• Photosensitizing Agents (pharmacology)
• Ribosomal Protein S6 Kinases, 70-kDa (metabolism)
• Sebaceous Glands (cytology, drug effects)
• Signal Transduction (drug effects)
• Sirolimus (pharmacology)
• TOR Serine-Threonine Kinases (metabolism)
• p38 Mitogen-Activated Protein Kinases (metabolism)