A mechanism of cell apoptosis by light irradiation

Da Xing; Xuejuan Gao; Fang Wang

doi:10.1117/12.644592

23 February 2006 A mechanism of cell apoptosis by light irradiation

Da Xing, Xuejuan Gao, Fang Wang

Proceedings Volume 6087, Biophotonics and Immune Responses; 60870I (2006) https://doi.org/10.1117/12.644592
Event: SPIE BiOS, 2006, San Jose, California, United States

Abstract

Light irradiation can modulate various biological processes. For instance, low-power laser irradiation (LPLI) can induce cell proliferation and differentiation. It has been used to treat diseases of regeneration limitation and to promote wound healing. The biological mechanism of light irradiation remains unclear. Our previous studies have shown that low fluence LPLI induced the proliferation of human lung adenocarcinoma cells (ASTC-a-1) through PKC channel, while high fluence LPLI induced caspase-3 activation and cell apoptosis. The mechanisms of the initiation and regulation of apoptosis are complex and diverse. There are two main pathways to initiate and regulate cell apoptosis, one is the death receptor pathway (receptor/caspase-8/caspase-3), and the other is the mitochondria pathway (mitochondria/ caspase-9/caspase-3). Using fluorescent imaging techniques, we observed a temporal sequence of events during apoptosis induced by high fluence LPLI and PDT. Both the high fluence LPLI and PDT triggers mitochondrial ROS production resulting in dissipation of ΔΨ_m and activation of caspase-3. Our results also show the two treatments do not activate caspase-8. These results suggest that caspase-3 activation induced by high fluence LPLI or PDT is initiated directly from mitochondria ROS generation and dissipation of ΔΨ_m, and independent of the cell death pathway involving caspase-8 activation. Because the progression of the apoptosis induced by high fluence LPLI is the same as that of PDT, we concluded that light is absorbed directly either by endogenous porphyrins or by the cytochromes in mitochondrion, resulting in initial ROS generation. During light irradiation induced apoptosis, apoptotic signals are initiated from mitochondrial ROS production due to photosensitization.

Citation Download Citation

Da Xing, Xuejuan Gao, and Fang Wang "A mechanism of cell apoptosis by light irradiation", Proc. SPIE 6087, Biophotonics and Immune Responses, 60870I (23 February 2006); https://doi.org/10.1117/12.644592

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
11 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Cell death

Fluorescence resonance energy transfer

Photodynamic therapy

Venus

Helium neon lasers

Luminescence

Laser irradiation

Show All Keywords

Keywords/Phrases

Search In:

Publication Years