Before the clatter of capsules against childproof caps came the whispering fields of medicinal plants - fields Nadja Cech knows very well.
Cech, 31, grew up on an organic farm in Oregon where her family tended medicinal herbs. Now she's an associate professor of chemistry at UNC Greensboro, studying how and why plants such as echinacea work as medicine in the body. She gathers plants across North Carolina, and sometimes from her family farm out West, to analyze back in her lab at UNCG.
"History tells us that nature has made a lot of compounds that end up beingvery useful drugs. So we can't really ignore nature when we're doing drug discovery and trying to come up with new drugs," Cech said, noting that plants are major components of pharmaceuticals.
In fact, she said, 25 percent of drugs on the market are based on natural products, and as many as 50 to 60 anticancer drugs, such as Taxol, have plant-based roots.
To build drugs with plant components, researchers have to know which compounds inside the plant to use. However, it's hard for researchers to figure out which compounds in plants are actually at work and beneficial to health.
Some scientists try to identify and isolate a single ingredient or compound to add to a drug and ignore the remaining components in the plant, Cech said. But that's a mistake, she said. She suspects that a number of compounds work together to help the body. So when researchers ignore how compounds interact, they may be missing out on useful combinations, she said.
"Dr. Cech is systematically studying a phenomenon that is widely touted by herbalists but rarely studied with scientific rigor: synergy between plant components," said David Kroll, a professor of pharmaceutical sciences at N.C. Central University, who isn't involved in the study.
Kroll says that although the relationship between components in plants isn't studied enough, researchers frequently study how chemicals in medicines react. For example, he said, researchers mix multiple drugs in cancer chemotherapy because the drugs are more effective when combined. The same is probably true of natural products: Many things interact to create an advantageous effect.
Cech has found just that. For nine years, she has studied echinacea, an herb said to stimulate the immune system, and goldenseal, an herb used to combat bacterial infections. Goldenseal contains a compound called berberine, which scientists pegged as responsible for the herb's bacteria-fighting power.
However, when researchers isolated berberine and tried to use the compound alone in drugs to stifle infection, it failed miserably. Something else makes the herb effective. Cech looks for these extra components, hoping to understand not only which compounds make berberine function to kill bacteria but also how they make the compound work.
Cech, operating her lab on a $200,000 grant from the National Institutes of Health, collaborates with farmers both in and outside the state to grow the herbs, which she and 10 or so student researchers sometimes harvest themselves. After gathering, Cech makes plant extracts and analyzes them with mass spectrometry, a technique that shows researchers the composition of the extracts and how much of a compound is present. Once she and her collaborators - including N.C. State University - find an extract of interest, Cech further separates it to find out how the extract works.
Jeanine Davis, an associate professor of horticultural science and extension specialist at N.C. State, grows crops for the project and collects herbs from all over North Carolina. She has worked with medicinal plants in the state for 22 years. When she cultivates echinacea and other herbs, she catalogs growing conditions, such as soil acidity and amount of light, that may affect the medicinal properties.
"Analyzing plant growing conditions makes the project unique," Davis said. "So much of the research being done on medicinal herbs hasn't been concerned (with) where that plant material is coming from."
Cech's lab hopes to decode the complexity behind different plants - from the intricacies of growing conditions to the riddle of extract makeup - specifically those herbs that have a history of use. This opposes science's recent movement toward synthetic compounds, which are often oversimplified but easier to make than natural compounds. But manufactured compounds don't always work as well as more complex plant-based alternatives, Cech said.
"Most of the world's population is still relying on alternative medicine as their primary source of health care, and a major portion of that is plants," Cech said. "There's certainly a lot of untapped wisdom there in terms of what people are using successfully that we don't understand, and alternative medicine can teach us a lot. We just need to learn the science behind it."
