Paul Gourley and colleagues at the US Department of Energy's Sandia National Laboratories have developed a nanolaser technique that can be used to accelerate screening for drugs that protect mitochondria and neurons.
“Our goal is make the brain less susceptible to diseases like Lou Gehrig’s,” says Sandia researcher Paul Gourley, a physicist who grew up in a family of doctors.
Preliminary work thus far has shown the biolaser (which recently won first place in the DOE’s annual Basic Energy Sciences’ competition for using light to quantify characteristics of anthrax spores) is able to measure mitochondrial size through unexpected bursts of light given up by each mitochondrion. The laser, using the same means, can also measure the swelling effect caused by the addition of calcium ions — the reaction thought to be the agent of death for both mitochondria and their host cells. The researchers expect to introduce neuroprotectant drugs into experiments this month, and be able to test hundreds of possible protective substances daily instead of two or three formerly possible.
“If we can use this light probe to understand how mitochondria in nerve cells respond to various stimuli, we may be able to understand how all cells make life or death decisions — a step on the road, perhaps, to longer lives,” says Gourley.
To do that, he says, scientists must understand how a cell self-destructs, which means understanding how mitochondria send out signals that kill cells as well as energize them.
If compounds can be found that protect mitochondria those compounds may protect neurons from the effects of many kinds of mitochondrial dysfunction and perhaps slow the accumulation of damage in mitochondria that occurs with age.
“Cyclosporin protects mitochondria better than anything else known, but it is not a perfect drug,” says Keep. “It has side effects, like immunosuppression. Unrelated drugs may have a similar protective effect on mitochondria. Gourley’s device will lead to a rapid screening device for hundreds of cyclosporin derivatives or even of chemical compounds never tested before.”
While testing with conventional methods would take many people and many batches of mitochondria, says Keep, the nanolaser requires only tiny amounts of mitochondria and drug to test.
“With one tube on the left flowing in a number of mitochondria per second, and microliters of different drugs in different packets flowing in to join them on the right, we could rapidly run through hundreds of different compounds. Each mitochondrion scanned through the analyzer would show if there were a change in its lasing characteristics. That would determine the effectiveness of chemical compounds and identify new and even better neuroprotectants.”
Of course this is just one step in a drug development process. All the compounds to be screened would still have to be synthesized. Also, any compounds which look good using this assay method would still need to be tested in whole cells, lab animals, and eventually humans. But this report is a sign of the times. Techniques that use micro-scale and nano-scale components to speed various laboratory procedures by orders of magnitude represent the future of biological science and biotechnological development.
|Share |||Randall Parker, 2003 September 23 02:57 PM Biotech Advance Rates|