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Nitric oxide may be best known as a pollutant, a molecule formed from the burning of nitrogen. It's in automobile exhaust and something the Environmental Protection Agency calls a major contributor to acid rain and smog. What, then, is it doing in the human body?

A lot, actually. Just ask Tadeusz Malinski, an Ohio University professor of biochemistry and two-time runner-up for the Nobel Prize. Malinski has spent more than 15 years studying nitric oxide, a molecule with the potential to improve the prevention and treatment of conditions from heart disease to Alzheimer's to diabetes.

In the past 10 years, research into nitric oxide systems has exploded, as the molecule has been discovered to be critical to the healthy functioning of the cardiovascular, nervous, and immune systems. This research has already contributed to the development of Viagra, and more advancements are on the way. The pace of discovery in the field is astounding, researchers say — from a few hundred scholarly papers published through the early 1990s to more than 60,000 today. While nitric oxide research has been around for decades, Malinski's development of a nanobiosensor to measure nitric oxide in the human body helped kick it into high gear.

NITRIC OXIDE IN ACTION

By the mid-1980s, researchers theorized that nitric oxide might play a role in the human body, particularly in the cardiovascular system. They observed how certain drugs — nitroglycerin, for example — causedblood vessels to relax and expand, and they linked that effect to nitric oxide. These conclusions, however, were based on deductions and suppositions, as no one had actually detected nitric oxide in action.

The problem was the nature of nitric oxide, a tiny molecule so unstable that it breaks down seconds after it's produced. Researchers could track the effects of what they concluded may be nitric oxide, but they couldn't see how it worked or why.

Enter Malinski. In 1992, while a professor at Oakland University in Rochester, Michigan, Malinski published an article in Nature describing a nanosensor his laboratory had developed that measured the nitric oxide released from a single cell by detecting an electrical signal generated by the molecule. “That paper was a seminal advance in the techniques for measuring nitric oxide,” says David Pinsky, division chief of cardiovascular medicine at the University of Michigan Medical School. “With Malinski's technique, one was finally able to just directly measure the molecule.”

Because the sensor could be implanted in a living organism, it could monitor the real-time dynamics and interaction of nitric oxide with other molecules and enzymes to achieve a comprehensive view of how a physiological system operated at the molecular level. The clarity and immediacy of the picture Malinski's sensor provided meant that researchers could characterize the progression of nitric oxide-related dysfunctions anywhere in the body and test potential treatments more effectively in a fraction of the time it formerly took.

“In the past, there may have been a lot of experiments done, but researchers might still not know the molecular basis of a disease,” Malinski says. But today, scientists can use nanotechnology to observe in real time the process that occurs in the single cells or neurons — and with far fewer experiments, he adds.

Malinski's technique has helped show that nitric oxide plays a variety of fundamental roles in the body, depending on where it's produced. In the cardiovascular system, for instance, it regulates blood pressure and inhibits coagulation. In the nervous system, neurons produce nitric oxide as a means to transmit information. And, in the immune system, white blood cells and other types of cells produce nitric oxide as a defense against cancer and pathogens.

“(His work has) really opened up all kinds of opportunities for research,” says R. Preston Mason, scientific director of Elucida Research and a professor at Brigham and Women's Hospital at Harvard Medical School. “It's just tremendous the number of applications for this technology.”

And not only is Malinski one of the pioneers of using micro- and nanotechnology to characterize physiological systems, but his peers say he is still one of the most productive researchers in the field, with more than 250 scholarly publications and a laundry list of major research awards to his name. Because the use of micro- and nanosensor technology in medical research is still relatively new, Malinski's long experience with applying it is invaluable to researchers who either collaborate with him directly or build on experiments he performs at his Ohio University laboratory.

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THE LABORATORY

“The currents that we measure … we are in the trillionths and quadrillionths of an amp,” Malinski says. “This level of current can be created when someone opens a door.”

Welcome to the challenges of diagnostic nanotechnology — the devices are so small and the measurements taken are so tiny that they're easily distorted or drowned out by elements of the everyday environment. Static, vibration, dust, and other factors can ruin an entire experiment or result in a false measurement. Because many molecules and other physiological components generate electrical signals, it's already a challenge to find the one you want, Malinski says, making it paramount that researchers control every outside variable they can.

That's why Malinski's laboratory sports controlled “clean” areas to perform implantations and manufacture nanosensors, which are too small to see with the naked eye, much smaller than a human hair. The equipment it requires to perform implantations and measure electrical signals — a powerful microscope, computer-controlled robotic arms, electrical equipment, and other components — is shielded to prevent electrical contamination from escaping into the environment. Super-heavy tables rest on pneumatic supports and sand to neutralize vibration.

The research has other specific needs, too. For example, Malinski must have both a heart and a brain surgeon available to perform implantations in animal subjects because their expertise is essential when working with nano-devices, he says.

The lab also includes visiting researchers and about 16 graduate and undergraduate biochemistry students, who receive broad exposure to many different scientific disciplines, Malinski notes, from solid-state physics and material science in the design and manufacture of the sensors to surgery and cellular biology during implantation and analysis of results.

The laboratory and team that Malinski oversees constitute one of the leading centers for medical nanobiosensor technology in the world, Pinsky says, a testament to Malinski's long experience with nitric oxide research and talent for designing quality experiments.

“There are people who claim to be able to do the same thing as Malinski,” he says, “but I've never really seen anything nearly as effective.”

Malinski says it was Ohio University's recognition of his research and its willingness to design and build a laboratory to his specifications that cemented his decision to move to the university in 2000. While he had many offers to join other institutions, both in the United States and abroad, he says he appreciated Ohio University's commitment to his work.

“The design was difficult,” he says. “But finally, the realization of the design was almost perfect. We can accelerate our research significantly working in this environment.”

On average, Malinski's laboratory conducts 12 projects at any given time, some wholly in-house and some in collaboration with researchers at medical schools, such as Columbia University, Harvard University, University of Michigan, the Mayo Clinic, and the University of Vienna. What follows are three of Malinski's projects he believes have the potential for bringing important new treatments to patients in the next few years.

WOUND HEALING

On one level, the healing of cuts or burns depends on the restoration of the tiny capillaries in the wounded area because they transport oxygen and food to build new tissue. At the molecular level, however, Malinski says, healing depends on re-establishing a healthy balance between nitric oxide and a group of molecules the body often produces in oxygen-starved systems that actually impede healing — oxidants.

In all wounds, the enzyme that is supposed to produce only nitric oxide also starts to generate a highly oxidative molecule called superoxide, he says. Superoxide rapidly consumes nitric oxide, and this event triggers further damage of the biological system and significantly inhibits the process of wound healing.

Without an ample supply of nitric oxide, the vascular system also not only has to fight to bring food and oxygen damaged areas — because nitric oxide speeds the creation of new capillaries — but it suffers diminished immune defenses because of nitric oxide's function in the immune system — helping cells fight bacteria.

To accelerate the restoration of the balance between nitric oxide and oxidants, Malinski and his laboratory have developed a new method of medical intervention that can be applied to wounds to boost production of nitric oxide. In animal models, the system has accelerated healing by more than 60 percent, Malinski says, meaning could shorten hospital stays, decrease the chance of infection, and, in the cases of diabetics and other patients with pre-existing conditions that impede healing, could save limbs and lives.

Because of intellectual property concerns, Malinski's team hasn't yet published details about its intervention, but the researchers are confident their understanding of the nitric oxide system is strong enough that a commercially available treatment is simply a matter of time, Malinski says. The Harvard Medical School and the Karolinska Institute Stockholm, Sweden, recently awarded Malinski a GEMI Fund Award to support this work. The award is given bi-annually for medical research related to the treatment, prevention, and diagnosis of diseases, and its recipients often go on to win the Nobel Prize, says Mason of the Harvard Medical School.

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HEART DISEASE IN AFRICAN AMERICANS

It is a well-known fact in the medical community that African Americans as a group suffer more severe and more frequent heart attacks and strokes than other racial groups in the United States. After lifestyle factors and other variables are accounted for, incidents of heart attack and stroke among African Americans are still five times higher and occur earlier in life than among other ethnic communities.

An article Malinski and his team recently published in the journal Circulation helps explain why and may lead to methods of prevention and treatment. The research was funded in part by the Marvin and Ann Dilley White Professorship Endowment at Ohio University; Malinski is the first professor to hold the Dilley professorship in biochemistry.

After three years of research on the cells of African Americans of varying ages, Malinski found that even at a young age, their potential to produce nitric oxide was actually greater than other races. The African-American vascular system, he says, produces two times the amount of nitric oxide synthase — the enzyme necessary to produce nitric oxide — than other races. But the system produces no greater amounts of the amino acid L-Arginine that nitric oxide synthase requires to generate nitric oxide. Instead, the system begins to produce harmful levels of oxidative molecules, as in a wound. These, in turn, attack and damage the cardiovascular system.

“You'll have a very high concentration of these toxic radicals and they will target DNA and RNA and damage them,” Malinski says. “At the age of 20 among African Americans, you have perhaps twice as much of these oxidants as in other groups, and that causes an acceleration of aging and the dysfunction of the entire cardiovascular system.”

With the understanding they've developed, however, Malinski believes that this imbalance can be treated early with existing drugs and that specialized new drugs could be developed that would slow this self-destructive process or even prevent it.

“What is amazing is that this system can be corrected very efficiently and at a relatively early age,” he says. “Based on our research, we can diagnose this dysfunction and probably — very soon — treat it, to some extent, with existing drugs.”

HEART TRANSPLANTATION AND PRESERVATION

One project Malinski has spent more than eight years working on — and one he has collaborated on with researchers from the University of Vienna, Columbia University, and the University of Michigan — is the preservation of hearts and other organs for transplantation. The amount of time it takes to remove a heart from a donor, transport it, and place it in a patient can be so damaging to the heart, he says, that the transplant is hardly worth the trouble. The surgery also is very expensive and complicated, he adds, and the transplanted heart may function for only a short period of time.

“A significant number of transplanted hearts will develop, very early, cardiac vasculopathy and may stop beating after one year or two,” he says. The problem, Malinski's team discovered, is related partly to the level of nitric oxide synthase still present when the heart is placed in the patient, which is directly related to its potential to produce nitric oxide once it begins beating again. In animal models, Malinski and his collaborators can now predict with 95 percent accuracy how long a transplanted heart will beat based on the amount of nitric oxide synthase present when it's put into a patient.

To combat degradation of nitric oxide synthase, Malinski's laboratory has developed a solution that preserves acceptable levels of nitric oxide synthase in organs more than 30 percent longer than the solutions currently used. Funded in part by grants from the National Institutes of Health, Malinski's research will significantly extend the organs' useful life after they're transplanted, he says.

WHAT'S NEXT ?

Working with never-before-possible insights at such a basic level of human physiology presents a challenge to Malinski, not because of the difficulty of his research but from the sheer potential of the impact his technology can have.

“It's very difficult because there are so many potential projects,” he says. “Sometimes it's overwhelming for me. It's scary how simple these systems are that so many people have spent so many years working on.”

His current projects include characterizing the progression of Alzheimer's and Parkinson's as it relates to the healthy functioning of nitric oxide systems in the nervous system to find methods of prevention; searching for ways to bolster the immune defenses of cells against bacteria, such as E. Coli; and developing an intervention that could minimize tissue and organ damage due to ischemia observed during heart attack, stroke, and clamping of arteries during surgery.

Widely available treatments based on his research could arrive in two to three years, Malinski says, pending clinical trials and the training of physicians and surgeons in the use of new techniques.

The temptation is there, he notes, to become a testing facility for new applications of existing drugs or treatments or for the development of new ones. But he prefers his laboratory to be more self-directed, to apply his unique experience and technology as widely as possible to explore how the body works and suggest new ways to treat and prevent disease and injury.

In medical science, where progress is normally slow and incremental, the insights his laboratory gains every year into how the human body works at its most basic level are amazing, Malinski says.

“We have been involved in research that has led us to several fundamental discoveries,” he says. “That doesn't happen in science very often.”

For more information about Malinski, visit the Web at http://www.ohio.edu/chemistry/malinski

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