Caffeine And Exercise May Prevent Skin Cancer

[Guest guest]

I do both! And I love the sunshine. :}}}

Caffeine And Exercise May Prevent Skin Cancer

31 Jul 2007

A new US study based on laboratory mice suggests that drinking low to

moderate amounts of caffeine and exercising regularly protects the

skin from damaging ultraviolet rays known to cause skin cancer. The

caffeine and exercise appear to work together to kill off precancerous

skin cells whose DNA has been damaged by ultraviolet B (UVB) rays. The

discovery is yet to be tested in humans.

The research took place at Lehman Cullman Laboratory for Cancer

Research at Rutgers University Ernest School of Pharmacy in the

state of New Jersey, and is published as an early online edition in

the Proceedings of the National Academy of Sciences (PNAS).

Skin cancer triggered by sun exposure is the most common type of

cancer in the United States, with over 1 million cases being diagnosed

each year, according to the National Cancer Institute.

In this experimental study the researchers, led by Dr Allan Conney,

Director of Rutgers' Cullman Laboratory, put hairless laboratory mice

into four groups. One group drank caffeinated water (equivalent to a

human drinking one or two cups of coffee a day). Another group of mice

took voluntary exercise on a wheel. The third group drank caffeinated

water and exercised, while the fourth (the control group) had no

caffeine and did not exercise.

All the mice were exposed to UVB light from laboratory lamps.

The scientists found that all four groups of mice had DNA damage in

their skin cells with varying degrees of apoptosis or programmed cell

death. However, the mice that drank caffeine and exercised showed the

most skin cell apoptosis compared to the control group.

Apoptosis is a series of biochemical events that leads to the death of

a cell so its remnants can be safely disposed of (unlike traumatic

cell death). When the DNA in a cell is badly damaged the cell can

become cancerous, unless it triggers this " cell suicide " , as Conney

explained:

" If apoptosis takes place in a sun-damaged cell, its progress toward

cancer will be aborted. "

" The differences between the groups in the formation of UVB-induced

apoptotic cells (those cells derailed from the track leading to skin

cancer), were quite dramatic, " he added.

Conney and colleagues were able to compare the extent of apoptosis in

the four groups of mice by looking for physical changes in the skin

cells and counting levels of biochemical markers such as caspase-3, an

enzyme involved in programmed cell death, and p53, a tumour suppressor.

Compared to the UVB exposed control group, they found that:

* The caffeine drinking group of mice had a 90 per cent increase

in apoptosis induced by UVB,

* The exercise group had a 120 per cent increase, and

* The caffeine and exercise group had a nearly 400 per cent increase.

The researchers attributed the dramatic difference between the

caffeine and exercise group and the others to " some kind of synergy "

between the caffeine and exercise that is working at the biochemical

level. And while they could speculate as to what that might be, it is

still a mystery that warrants further investigation, and eventually

also doing human tests.

Conney explained:

" We need to dig deeper into how the combination of caffeine and

exercise is exerting its influence at the cellular and molecular

levels, identifying the underlying mechanisms. "

" With an understanding of these mechanisms we can then take this to

the next level, going beyond mice in the lab to human trials. With the

stronger levels of UVB radiation evident today and an upward trend in

the incidence of skin cancer among Americans, there is a premium on

finding novel ways to protect our bodies from sun damage, " he added.

" Voluntary exercise together with oral caffeine markedly stimulates

UVB light-induced apoptosis and decreases tissue fat in SKH-1 mice. "

Yao-Ping Lu, Bonnie Nolan, You-Rong Lou, Qing-Yun Peng, C.

Wagner, and Allan H. Conney.

PNAS Published ahead of print July 30, 2007

DOI: 10.1073/pnas.0705839104

Click here for Abstract.

Written by: Catharine Paddock

Copyright: Medical News Today

Not to be reproduced without permission of Medical News Today

Article URL: http://www.medicalnewstoday.com/articles/78306.php

Main News Category: Cancer / Oncology

Also Appears In: Nutrition / Diet, Sports Medicine / Fitness,

Here's the abstract:

Proc. Natl. Acad. Sci. USA, 10.1073/pnas.0705839104

This Article

Right arrow Full Text (PDF)

Right arrow Alert me when this article is cited

Right arrow Alert me if a correction is posted

Services

Right arrow Similar articles in this journal

Right arrow Similar articles in PubMed

Right arrow Alert me to new issues of the journal

Right arrow Add to My File Cabinet

Right arrow Download to citation manager

Right arrow Request Copyright Permission

Google Scholar

Right arrow Articles by Lu, Y.-P.

Right arrow Articles by Conney, A. H.

PubMed

Right arrow PubMed Citation

Right arrow Articles by Lu, Y.-P.

Right arrow Articles by Conney, A. H.

Pharmacology

Voluntary exercise together with oral caffeine markedly stimulates UVB

light-induced apoptosis and decreases tissue fat in SKH-1 mice

( methylxanthines | physical activity | programmed cell death | skin

cancer | sunburn )

Yao-Ping Lu *, Bonnie Nolan {dagger}, You-Rong Lou *, Qing-Yun Peng *,

C. Wagner {dagger}{ddagger}, and Allan H. Conney *{sect}

* Lehman Cullman Laboratory for Cancer Research, Department of

Chemical Biology, Ernest School of Pharmacy, {dagger}Department

of Neuroscience, and {ddagger}Department of Psychology, Rutgers, the

State University of New Jersey, Piscataway, NJ 08854

Contributed by Allan H. Conney, June 21, 2007 (sent for review April

17, 2007)

Treatment of SKH-1 mice orally with caffeine (0.1 mg/ml in the

drinking water), voluntary running wheel exercise, or a combination of

caffeine and exercise for 2 weeks (i) decreased the weight of the

parametrial fat pads by 35, 62, and 77%, respectively; (ii) decreased

the thickness of the dermal fat layer by 38, 42, and 68%,

respectively; (iii) stimulated the formation of UVB-induced apoptotic

sunburn cells in the epidermis by 96, 120, and 376%, respectively; and

(iv) stimulated the formation of UVB-induced caspase 3 (active

form)-positive cells in the epidermis by 92, 120, and 389%,

respectively (average of two experiments). Oral administration of

caffeine (0.4 mg/ml in the drinking water) in combination with

voluntary exercise was less effective than administration of the low

dose of caffeine in combination with exercise in stimulating

UVB-induced apoptosis. Although orally administrated caffeine (0.1

mg/ml in the drinking water) or voluntary exercise for 2 weeks caused

only a small nonsignificant stimulation of UVB-induced increase in the

percentage of phospho-p53 (Ser-15)-positive cells in the epidermis (27

or 18%, respectively), the combination of the two treatments enhanced

the UVB-induced increase in phospho-p53 (Ser-15)-positive cells by

99%. The plasma concentration of caffeine in mice ingesting caffeine

(0.1-0.4 mg/ml drinking water) is similar to that in the plasma of

most coffee drinkers (one to four cups per day). Our studies indicate

a greater than additive stimulatory effect of combined voluntary

exercise and oral administration of a low dose of caffeine on

UVB-induced apoptosis.