Infectobesity refers to the research that studies the relationship between pathogens and weight gain.
As a topic, obesity has been ever-present in Nikhil Dhurandhar's life for as long as he can remember.
His father is considered the father of obesity practice in the Indian medical community, and when he went to medical school, Dhurandhar knew his passion was in obesity treatment.
“I often saw the difficulties that people suffering from obesity face and how quacks take them for a ride,” he said. “I pondered about what could be done for them.”
Dhurandhar, who recently became the first chairman of the newly created Department of Nutritional Sciences, found career success in treating obesity but was frustrated because his patients were unsuccessful in keeping the weight off. He kept seeing the same patients going through the same cycle of losing and gaining weight. Although there were a few individual success stories, on the whole the results were less than optimal.
That question became his cause célèbre, taking his family from India to North Dakota to Texas Tech studying chickens and investigating viruses as one possible cause of obesity. He continues this research while leading a department with several disparate areas of research.
“There is much more to nutrition than obesity,” he said. “Also, there is more to obesity than nutrition. Both are true.”
Asking Questions About Obesity
Dhurandhar took a hiatus from his medical practice to come to the United States in the 1980s for a master's degree in nutrition, then returned to Bombay, India, for a doctorate in biochemistry. While there he heard a lecture from S.M. Ajinkya, a well-known veterinary pathologist, who talked about an avian virus killing thousands of chickens a day. These chickens died fat instead of emaciated.
“I reasoned, if a bird dies of a viral infection it should have no fat, and you're describing plenty of fat,” Dhurandhar remembers asking. “Is this virus making those chickens fat?
“What Dr. Ajinkya said in response changed everything. He said, 'I don't know.' Then he said, 'You're doing a Ph.D. Why don't you find out?'”
He did. Dhurandhar performed three experiments with this adenovirus, the first two with chickens and the third involving humans. He found that, after injecting chickens with the virus, they gained weight in just a few weeks.
While he couldn't inject humans with the virus for ethical reasons, he obtained blood samples from patients who came into his clinic for obesity treatment and discovered that about 20 percent of the patients had antibodies for the virus, which meant they'd been infected at some point. The three experiments indicated this virus did cause obesity in animals and humans infected with it.
The studies showed another, less expected, relationship. Dhurandhar said typically symptoms like high blood sugar, high cholesterol and high triglycerides accompany obesity. However, both the chickens and the humans who'd had the virus were obese but had low cholesterol and low triglycerides, suggesting an association between the virus and a patient's metabolic health.
“When we had three experiments back to back I was sold on this concept,” he said.
Pioneering the Field of Infectobesity
Selling the concept to others turned out to be a much bigger challenge. Although this field, which he called infectobesity – obesity of infectious origin – is well-established now, 20 years ago this research flew in the face of prevailing wisdom.
“People tend to view obesity as, 'just push yourself away from the table,'” he said.
The cause of obesity, according to all the key players, was limited to two things: eating too much and exercising too little. Today, the American Medical Association and other organizations have declared obesity a disease, and the mindset is changing. Twenty years ago scientists weren't looking for theories or viruses; they had calorie counts.
This made finding a U.S. lab to support Dhurandhar's research in viruses and obesity difficult. Dhurandhar sent letters and made phone calls to research labs throughout the United States, looking for someone interested in his research. When no one responded favorably, he took a postdoctoral fellowship in any area, ending up at North Dakota State University in Fargo. For two years he studied the biochemistry of sunflower pectin enzymes and wrote hundreds of letters seeking a lab that would allow him to engage in researched related to infections and obesity.
After one year and 11 months, after he and his wife decided to return to India and secured their son's school tuition in Bombay, he got a call from a researcher at the University of Wisconsin inviting Dhurandhar to join his lab.
Once there, he found he couldn't import the Indian adenovirus he'd originally experimented with, so he picked up the catalog to find a different virus. There were 50 different viruses. Going with his gut, he picked No. 36 and replicated his Indian experiments.
“The very first experiment showed the human adenovirus Ad36 fattened chickens but reduced their cholesterol and triglycerides, just like the Indian virus,” he said. “Ad36 clicked.”
He replicated the experiment in a number of different animal models including rats, mice and monkeys, with the same results. Over time, the scientific and medical communities accepted Dhurandhar's conclusions, and the field of infectobesity was born. His research also contributed to the realization that obesity is more complicated than overall caloric intake.
“In my opinion the word obesity is sort of misleading,” he said. “The actual word should be obesities because there are so many different types.
“There are multiple contributors to the obesity epidemic. We generally tend to focus on eating too much and not moving enough.”
Today Dhurandhar's research is split between obesity and diabetes, both related to this obesity-causing virus. He applied the evidence-based association between the virus and lower blood sugar and cholesterol to diabetes, of which high blood sugar is a symptom. He is working to isolate the protein in the virus that improves metabolic numbers so it can be administered to diabetics to lower their blood sugar.
He hasn't left the field of obesity research, though. Dhurandhar believes that because some cases of obesity are caused by a virus, researchers can create a vaccine for this virus, which could prevent this type of obesity.
“Why all of this is important is because today we have only a blanket treatment of obesity, regardless of the cause,” he said. “We tell people to eat less and move more, in some rare cases use drugs and in rarer cases use surgery. That's what we've got. You mostly don't consider your various causes of obesity in any of these treatments. That may be why we're getting limited success.
“If we want to improve success, perhaps we should have cause-specific treatment. And how can you have cause specific treatment if you don't know what the causes are? Hence, we need a better and clearer understanding of the contributors of obesity.”
For most of his career, Dhurandhar had time to focus on obesity but little else. As his research evolved, he became a diabetes expert. As chairman of the Nutritional Sciences department, he gets to focus on promoting and administering 16 different labs focused on different aspects of nutrition.
Dhurandhar came to Texas Tech from Pennington Biomedical Research Center at Louisiana State University. He wants to continue his research here, but he also wants the opportunity to interact with the community and other researchers outside of his field.
“It's attractive to me to work with students, faculty and researchers from our departments and others on issues of nutrition and obesity and collectively advance research, training and understanding in this field,” he said. “That's what I always wanted to do.
“We are mapping so many areas. What that does is allow us to cover a large territory and collaborate with each other.”
He is the first chairman of this department, which College of Human Sciences Dean Linda Hoover created in September when she separated the Department of Nutrition, Hospitality and Retailing into Nutritional Sciences and the Department of Hospitality and Retail Management.
“Dr. Dhurandhar is uniquely qualified to lead our new department, as he has had significant administrative experience and a strong record of collaboration with colleagues in fields related to nutrition,” Hoover said. “In addition, he has mentored a number of new scientists, so our new faculty will directly benefit from his guidance. I know Dr. Dhurandhar will provide strong leadership to our new Department of Nutritional Sciences and our academic programs. Based on all of these factors, his efforts will enable the department to increase contributions to the field of nutrition.”