In this Q & A, University of Alberta alumnus Errol B. Marliss, '64 MD, discusses the role his mentors and peers played in sparking more than four decades of research interest in protein metabolism and nutrition in diabetes and obesity.
What was the point that you realized you wanted to focus on diabetes research?
This conjures up the saying: "Chance favors the prepared mind." In my case, a good deal of serendipity played a role as well.
My first exposure to research was as a summer medical student in Dr. Lionel McLeod's lab. He was both endocrinologist and nephrologist at the time. He had trained in part in Montreal, and encouraged me to go there for residency.
I then went to Boston (Boston U) for a research fellowship in nephrology, where I became more interested in the metabolic aspects of kidney disease. A chance opportunity led me to continue at the Joslin Research Lab (Harvard) under Dr. George F. Cahill Jr., the person who instilled my interest in protein in human obesity and diabetes, which continues to this day. My third research fellowship continued this in Geneva, Switzerland, with Dr. Albert E. Renold, in animals with spontaneous obesity and diabetes.
On a personal note, my father had diabetes, as did most of his siblings.
You are returning to the U of A as guest speaker on September 18, delivering a lecture called, "The convergence of insulin resistance of glucose and protein metabolism: clinical implications," as part of the Faculty of Medicine & Dentistry's Dean's Lecture Series, hosted by the Alberta Diabetes Institute.
Tell us about the topic of your lecture.
When we think of diabetes, we think sugar. The major reasons sugar (glucose) levels are high in diabetes is that there is not enough insulin, that our insulin does not work effectively-or both. Insulin controls not only sugar, but also fat and protein metabolism. Our body proteins all have essential functions. With or without diabetes, if we eat less than we need, we burn not only our stored fat but also proteins, to fill the gap. This can cause loss of muscle, where most protein is located. But all proteins in the body have essential functions that can be affected.
When insulin increases, glucose in the blood normally goes down because it is picked up by the tissues, and less is made in the liver. At the same time, insulin both stops protein breakdown and stimulates its buildup. If insulin is insufficient, these do not happen normally.
What is insulin resistance?
Everyone thinks automatically of effects on glucose. What this means is that a normal amount of insulin is not effective in controlling glucose, and keeping metabolism normal requires more to be secreted. It occurs in many diseases. It can be severe in obesity, and is worst in type 2 diabetes.
There are different ways of measuring insulin resistance. The simple ones are only "surrogates" in that they are approximate. The accepted "gold standard" method is the one my colleagues and I have used in our studies called the "hyperinsulinemic clamp." We have adapted it to measure glucose and protein metabolism simultaneously. It includes simulating what happens after a meal (the fed state), when most protein is built up in the tissues.
In all insulin-resistant people we studied, their protein metabolism is abnormal to the same extent that glucose metabolism is abnormal. This includes not only in obesity and diabetes, but also in usual aging and in people with cancer. Most recently we found that otherwise normal offspring of parents with type 2 diabetes also have protein abnormalities that go along with their known insulin resistance of glucose metabolism.
How can your research be translated into improved diabetes treatments?
More research is required to test what its implications might be. Having firmly established the insulin resistance of protein metabolism has already contributed to changes in protein intake recommendations by both Diabetes Canada and the American Diabetes Association. One could envision protein intakes eventually being adjusted to the level of individual glucose control, as its metabolism appears to worsen as levels rise above normal.
There is controversy about higher protein intake being associated with developing diabetes and worsening it when present. Our results do not support this. Our fed state studies showed that abundant protein supply actually compensates for the insulin resistance. It restored normal protein metabolism, without worsening the metabolism of glucose, as others have suggested.
Finally, sensitizing health care professionals by bringing this area to the forefront could lead to more day-to-day emphasis on protein in many therapeutic dietary prescriptions.
Are you still connected with U of A classmates from your '64 MD graduating class?
It had been difficult because we are so far away from one another, except at the many reunions that Fred Wilson (neurologist) has worked so hard to organize. After my speaking engagement in Edmonton on September 18 as part of the Dean's Lecture Series, I'll be going to Victoria to visit with Don Russell (radiologist), the one I have kept in touch with the most and is a close friend.
Though not a classmate, we will get together there as well with Eliot Gelfand, the cardiac surgeon who saved my mother's life. Classmates Shaun Robinson (urologist) and Adrian Jones (pediatric gastroenterologist) took my mother on as a project in my absence and remained in close touch with her, especially in her declining years. Garner King was the person I was closest to in Edmonton, and intermittently until his untimely death. He graduated the year ahead of me.
Do you have other connections to the U of A?
My late mother, Dr. Ethel Marliss (U of A Honorary Doctorate of Letters, 1989) was a self-taught consumer advocate, becoming well known for her work. She made her first broadcasts on CKUA, the U of A campus radio station, in 1945. She went on to be a columnist for the Edmonton Sun and a broadcast journalist on CBC Radio and intermittently on TV. She was something of a legend in consumer education for decades.
Even before becoming very sick, my mother was passionate about doctor-patient communications. I learned the importance of this as a medical student, and it will remain a memory I draw on for the rest of my life. Upon exiting the room of a patient with a terminal illness, Dr. Alan Gilbert once told me, "if the patient does not feel even the slightest better because of your visit, then you have failed in your role, even if you know there is nothing more that you can do." I share this piece of wisdom with students and residents incessantly.
In honour of our mother, my brother Garry (BSc '60, MSc '63) and I set up the annual Ethel Marliss Award for Excellence in Patient Communication (Division of General Internal Medicine, Department of Medicine) for a medical resident in who excels in patient-doctor communications.
She was in close touch with the department head and faculty members in what was called when the Household Economics Department. She was proud of having gone as far as she did with only Grade 10 education. Many U of A people knew her, including former presidents Walter Johns (1959-1969), Max Wyman (1969-1974) and possibly even Andrew Stewart (1950-1959).
Marliss returns to his alma mater as guest speaker on September 18 at 12 p.m. in 1-040 Li Ka Shing Centre for Health Research Innovation, delivering the lecture "The convergence of insulin resistance of glucose and protein metabolism: clinical implications" as part of the Faculty of Medicine & Dentistry's Dean's Lecture Series, hosted by the Alberta Diabetes Institute.