Knowing Networks

1 comment
Artist's rendition of a network diagram. Credit: Allison Kudla, Institute for Systems Biology.
Artist’s rendition of a network diagram. Credit: Allison Kudla, Institute for Systems Biology.

Networks—both real and virtual—are everywhere, from our social media circles to the power grid that delivers electricity. The interactions of genes, proteins and other molecules in a cell are examples of networks, too.

Scientists working in a field called systems biology study and chart living networks to learn how the individual parts work together to make a functioning whole and what happens when these complex, dynamic systems go awry. For example, the network diagram here depicts yeast cells (superimposed circles) and the biochemical “chatter” between them (lines) that tells the cells to gather together in clumps. This clumping helps them survive stressful conditions like a shortage of nutrients.

Network diagrams provide more than just hub-and-spoke pictures. They can yield information that helps us better understand—and potentially influence—complex phenomena that affect our health.

Read more about network analysis and systems biology in this Inside Life Science article.

Multitarget Drugs to Challenge Microbial Resistance

0 comments
A group of purple, rod-shaped bacterial cells rendered by computer at Centers for Disease Control and Prevention by Melissa Brower.
Computer-generated image of drug-resistant Mycobacterium tuberculosis bacteria. Credit: Melissa Brower, Centers for Disease Control and Prevention.

Drugs that target a single essential protein in a microbial invader can be effective treatments. But the genomes of pathogens—including bacteria, fungi and parasites—mutate rapidly, and resistance can develop if a mutation changes a target protein’s structure. Molecules that interfere with multiple microbial proteins at once have the potential to overcome the growing problem of antimicrobial drug resistance.

Researchers led by Eric Oldfield of the University of Illinois recently explored whether an experimental drug called SQ109, developed to treat tuberculosis (TB), could be tweaked to attack multiple enzymes, as well as to kill different types of microbes. The scientists succeeded in creating several multitarget analogs of SQ109 that were more effective than the original drug at killing their target pathogens in laboratory experiments. These analogs included one compound that was five times more potent against the bacterium that causes TB while also being less toxic to a human cell line tested.

This work was also funded by the National Cancer Institute; the National Heart, Lung, and Blood Institute; the National Institute of Allergy and Infectious Diseases and the NIH Office of the Director.

Learn more:
University of Illinois, Urbana-Champaign News Release exit icon

A Medicine’s Life Inside the Body

0 comments
Heart
Most often, the bloodstream is the vehicle for carrying medicines throughout the body. Credit: Stock image.

Pharmacology is the scientific field that studies how the body reacts to medicines and how medicines affect the body. Scientists funded by the National Institutes of Health are interested in many aspects of pharmacology, including one called pharmacokinetics, which deals with understanding the entire cycle of a medicine’s life inside the body.

Knowing more about each of the four main stages of pharmacokinetics—absorption, distribution, metabolism and excretion—aids the design of medicines that are more effective and that produce fewer side effects.

Read more about a medicine’s life inside the body in this Inside Life Science article.

Understanding Complex Diseases Through Computation

2 comments
Scientists developed a computational method that could help identify various subtypes of complex diseases. Credit: Stock image

Complex diseases such as diabetes, cancer and asthma are caused by the intricate interplay of genetic, environmental and lifestyle factors that vary among affected individuals. As a result, the same medications may not work for every patient. Now, scientists have shown that a computational method capable of analyzing more than 100 clinical variables for a large group of people can identify various subtypes of asthma, which could ultimately lead to more targeted and personalized treatments. The research team, led by Wei Wu Exit icon of Carnegie Mellon University and Sally Wenzel of the University of Pittsburgh, used a computational approach developed by Wu to identify several patient clusters consistent with known subtypes of asthma, as well as a possible new subtype of severe asthma that does not respond well to conventional drug treatment. If supported by further studies, the researchers’ proposed approach could help improve the understanding, diagnosis and treatment not just of asthma but of other complex diseases.

This work also was funded by NIH’s National Heart, Lung, and Blood Institute.

Learn more:
Carnegie Mellon University News Release Exit icon

The Inner Life of Nerve Cells

2 comments
“Before this research, we didn’t even know that neurons had this special mechanism to control neuropeptide function. This is why we do basic research. This is why it’s important to understand how neurons work, down to the subcellular and molecular levels.”—Kenneth Miller”

Nerve cells (neurons) in the brain use small molecules called neuropeptides to converse with each other. Disruption of this communication can lead to problems with learning, memory and other brain functions. Through genetic studies in a model organism, the tiny worm C. elegans, a team led by Kenneth Miller of the Oklahoma Medical Research Foundation has uncovered a previously unknown mechanism that nerve cells use to package, move and release neuropeptides. The researchers found that a protein called CaM kinase II, which plays many roles in the brain, helps control this mechanism. Neuropeptides in worms lacking CaM kinase II spilled out from their packages before they reached their proper destinations. A more thorough understanding of how neurons work, provided by studies like this, may help researchers better target drugs to treat memory disorders and other neurological problems in humans.

This work also was funded by NIH’s National Institute of Mental Health.

Learn more:
Oklahoma Medical Research Foundation News Release Exit icon
Using Model Organisms to Study Health and Disease Fact Sheet

Two Proteins That Regulate Energy Use Play Key Role in Stem Cell Development

0 comments
Stem cells. Credit: Julie Mathieu, University of Washington.
The protein HIF1 alpha is beneficial for creating induced pluripotent stem cells (green) from adult human cells. Credit: Julie Mathieu, University of Washington.

Hannele Ruohola-Baker and a team of researchers at the University of Washington recently discovered that two proteins responsible for regulating how cells break down glucose are also essential for stem cell development. The scientists showed that the proteins HIF1 alpha and HIF2 alpha are both required to reprogram adult human cells into pluripotent stem cells, which have the ability to mature into any cell type in the body. Taking a closer look at what each protein does on its own, the researchers found that HIF1 alpha was beneficial for reprogramming throughout the process, whereas HIF2 alpha was required at early stages but was detrimental at later stages of reprogramming. Because the two proteins also play a role in transforming normal cells into cancer cells, the findings could lead to future advances in cancer research.

Learn more:
University of Washington News Release Exit icon
Ruohola-Baker Lab Exit icon
Once Upon a Stem Cell Article from Inside Life Science
Learning About Cancer by Studying Stem Cells Article from Inside Life Science
Sticky Stem Cells Article from Inside Life Science

How Cells Take Out the Trash

1 comment
Proteins entering the proteasome. Credit: Office of Biological and Environmental Research of the U.S. Department of Energy Office of Science.
When proteins enter the proteasome, they’re chopped into bits for re-use. Credit: Office of Biological and Environmental Research of the U.S. Department of Energy Office of Science.

As people around the world mark Earth Day (April 22) with activities that protect the planet, our cells are busy safeguarding their own environment.

To keep themselves neat, tidy and above all healthy, cells rely on a variety of recycling and trash removal systems. If it weren’t for these systems, cells could look like microscopic junkyards—and worse, they might not function properly. Scientists funded by the National Institutes of Health are therefore working to understand the cell’s janitorial services to find ways to combat malfunctions.

Read more about how cells take out the trash and handle recycling in this Inside Life Science article.

Basic Research Fuels Medical Advances

0 comments
Genetic defect that causes myotonic dystrophy type 2 and used that information to design drug candidates to counteract the disease. Credit: Ilyas Yildirim, Northwestern University.
Scientists revealed a detailed image of the genetic change that causes myotonic dystrophy type 2 and used that information to design drug candidates to counteract the disease. Credit: Ilyas Yildirim, Northwestern University. View larger image

This image may look complicated, but it tells a fairly straightforward tale about basic research: Learning more about basic life processes can pave the way for medical and other advances.

In this example, researchers led by Matthew Disney of the Scripps Research Institute’s Florida campus focused on better understanding the structural underpinnings of myotonic dystrophy type 2, a relatively rare, inherited form of adult-onset muscular dystrophy. While this work is still in the preliminary stages, it may hold potential for someday treating the disorder.

Some 300,000 NIH-funded scientists are working on projects aimed at improving disease diagnosis, treatment and prevention, often through increasing understanding of basic life processes.

Read the complete Inside Life Science article.

New Life for Toxic Antibiotics?

0 comments
Pills and a bottle
Researchers found that the antibiotic trovafloxacin cuts off a channel for communication between cells and interferes with a cell-death process. Credit: Stock image.

Many compounds that show promise as new antibiotics for treating bacterial infections never make it to the clinic because they turn out to be toxic to humans as well as to bacteria. A research team led by Kodi Ravichandran of the University of Virginia recently gained insights into why one such antibiotic, trovafloxacin, harms human cells. They found that the compound cuts off a channel for communication between cells, which in turn interferes with how dying cells are broken down and recycled by the body. Roughly 200 billion cells in the human body die and are replaced every day as part of a routine cleanup process, and interference in this process by trovafloxacin may have contributed to the serious liver damage seen in some patients in clinical trials of the drug. Understanding how trovafloxacin causes toxicity in people may help researchers re-engineer this and related compounds to make them safe and effective for use in fighting bacterial infections.

Learn more:
Ravichandran Lab

Meet Jeff Shaman

0 comments
Jeff Shaman
Jeff Shaman
Field: Climatology
Works at: Columbia University’s Mailman School of Public Health, N.Y.
Favorite high school subject: Biology
First job: Guide at the Franklin Institute in Philadelphia, Pa.
Alternative career: Opera singer
Credit: Anne Foulke

Before he wrote any scientific papers, Jeff Shaman wrote operas. At the premiere of one of his operas, an 80-minute story about psychoanalysis, reviewers said the work “crackle[d] with invention.”

After 4 years of training to become an opera singer, Shaman realized that the work wouldn’t offer him career stability. He started thinking about his other interests. After college, where he majored in biology with a focus on ecology, he had volunteered to help with HIV clinical trials and developed a fascination with understanding infectious diseases. He wondered if the quantitative tools and methods used to study the physical sciences—another interest area—could inform how contagions spread and possibly even lead to systems for monitoring or predicting their transmission.

So Shaman returned to school—this time, for advanced degrees in earth and environmental sciences. He now studies the relationship between soil wetness and mosquito-borne diseases such as malaria in Africa and West Nile in Florida.

“I love science—probing questions, thinking about problems, finding solutions, pursuing my ideas,” says Shaman.

His Findings

A few years ago, Shaman took some of his scientific compositions in another direction by focusing on seasonal flu outbreaks. For more than 60 years, researchers have linked seasonal flu outbreaks with environmental data like humidity and temperature. Shaman analyzed this work and figured out that absolute humidity, rather than relative humidity, was the best predictor of outbreaks. Now he’s applied state-of-the-art mathematical modeling and real-time observational estimates of influenza incidence to predict when outbreaks will likely occur.

His forecasting technique mimics that used by meteorologists to predict weather conditions like temperatures, precipitation and even hurricane landfall. Shaman’s version incorporates variables like how transmissible a virus is, the number of days people are contagious and sick, and how much humidity is in the air.

The flu forecasts build on a series of studies in which Shaman and his colleagues used data from previous influenza seasons to test their predictions and improve reliability of their model. The work culminated with real-time predictions for 108 cities during the 2012-2013 influenza season. The forecasts could reliably estimate the peaks of flu outbreaks up to 9 weeks before they occurred.

For the 2013-2014 flu season, the researchers continued to make weekly predictions. But instead of first publishing the results in a scientific journal, they posted them on a newly launched influenza forecasts Web site Exit icon where the public could view the projections.

“People understand the limitations and capabilities of weather forecasts,” says Shaman. “Our hope is that people will develop a similar familiarity with the flu forecasts and use that information to make sensible decisions.” For instance, the prediction of high influenza activity may motivate them to get vaccinated and practice other flu-prevention measures.

As he waits for the start of the next flu season, Shaman continues to tweak his forecast system to improve its reliability. He’s also beginning to address other questions, such as how to predict multiple outbreaks of different influenza strains and how to predict the spread of other respiratory illnesses.

Learn more:
Influenza Forecasts Web Site Exit icon