That horse grazing in the pasture may save a child from an emergency room visit during an asthma attack. Both horses and humans may benefit from Dr. Virginia Buechner-Maxwell's work as a large animal veterinarian and former post-doctoral fellow in pulmonary medicine.
Buechner-Maxwell, a professor of clinical services, medicine, and equine and production management medicine in the Department of Large Animal Clinical Sciences at the Virginia-Maryland Regional College of Veterinary Medicine, is conducting a career-long investigation of human asthma and related equine disorders of heaves and inflammatory airway disease.
This type of research is called translational medicine because it compares human diseases with the same diseases in animals. Buechner-Maxwell found her calling while working as a post-doctoral fellow in the University of Michigan School of Medicine's Department of Pulmonary Medicine and Critical Care.
“That experience helped me realize just how much researchers had to manipulate mouse models of human asthma to simulate disease and how little the models actually mimicked the real disease,” she said. “I think being a veterinarian gave me a unique comparative perspective that assisted me in arriving at this realization. It motivated me to look more closely at unconventional models, which is why I became so interested in working with heavey horses.”
Her research comparing equine breathing disorders and human asthma is important because about 25.7 million asthmatics live in the United States. In some regions of the world as much as half the horse population is afflicted by one of the breathing disorders.
Asthma accounts for 1.1 million non-emergency hospital visits, 1.9 million emergency room visits, and 440,000 hospitalizations in the United States each year, according to Centers for Disease Control and Prevention (CDC). Approximately 3,400 people die from asthma attacks annually.
Most asthma begins at birth or in childhood, and about 9.4 percent of American children — about 7 million — were diagnosed with the disease, according to CDC figures available in spring 2012. The disorder also can develop or worsen in adulthood.
The majority of people with asthma can be treated and continue activities they love. But why asthma occurs is unknown, and there is no cure.
Scientists do know that equine and human immune responses are triggered by such things as pollen, dust, exercise, weather, and debris from mites. When the immune system battles invasive materials, the airways become inflamed, mucus builds up, and airway muscles tighten.
“Horses are superb models for studying airway diseases because they develop these illnesses spontaneously like humans,” Buechner-Maxwell said. “They also are the only animal besides people that experience chronic changes in the disease as they age.”
She is studying the reasons for airway inflammation and associated changes to airways, as well as how the treatments affect immune response and the long-term ramifications.
Horse heaves are similar to asthma in older people because both may experience worsening disease and long-term lung damage. Horses also experience a disease that shares some similarities with human pediatric asthma. This form is known as equine inflammatory airway disease and usually affects younger horses.
In either case, treatment for horses and people is the same: keeping them away from the triggers as much as possible and taking some of the same drugs. Horses can be fitted with mask-type devices that cover their nostril and allows them to breath in the medication just like people.
“Because horses and humans respond to similar therapies, information learned from studying horses may allow us to better understand how these medications affect people,” Buechner-Maxwell said.
Horses are an ideal model because researchers can evaluate their lung function and take blood samples without harming the animal. In addition, horses age more rapidly than humans so results of immune responses, drug effects, and long-term disease progression can be studied faster. This is especially important because one of the research goals is to better understand chronic lung and bronchial tube changes that occur in people and animals with life-long airway disease.
“My hope is that by better understanding the events that lead to the ‘inappropriate’ response of the immune system in diseases like heaves and asthma, more can be learned about what promotes and maintains the normal immune response,” Buechner-Maxwell said.
Dr. Virginia Buechner-Maxwell talks about her research in this video.
Research and improved treatment of asthma is only one area of medicine that humans and other animals share. Veterinarians can provide the family dog or cat, the show horse, and livestock with many of the same medical and surgical treatments that your doctor provides to members of your family.
Cardiac pacemakers, artificial joints, ultrasounds, MRIs, and state-of-the-art cancer treatment are all available for animals. The Virginia-Maryland Regional College of Veterinary Medicine, founded in 1978, provides these types of services both in its clinics and through mobile units that travel to farms.
The college has three campuses. The main clinical facility is in Blacksburg, Va., on the Virginia Tech campus. The Marion duPont Scott Equine Medical Center is in Leesburg, Va. The third campus is the Avrum Gudelsky Veterinary Center, a teaching/research facility at College Park, Md.
When she was young, Virginia Buechner-Maxwell learned about human and equine breathing disorders. Her mother had severe asthma and her first horse had heaves. Her interest in the science behind the disease and the treatment sparked when she attended seminars given by an immunology research group while studying for a master’s degree at the University of Pennsylvania.
As my understanding of the immune system grew,” she recalled, “I became specifically interested in understanding the events that direct and regulate the immune response because it seems to me that a responsive, well-regulated immune system is critical to good health.”
Buechner-Maxwell is a professor of clinical services, medicine, and equine and production management medicine in the Department of Large Animal Clinical Sciences at the Virginia-Maryland Regional College of Veterinary Medicine.
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