An upcoming virtual lecture will outline the various stages of insulin’s journey through the body and the cell biology that underlies its interaction with each organ.

Dr. Amira Klip, a senior scientist in the cell biology program of Toronto’s Hospital for Sick Children and a professor of paediatrics, biochemistry and physiology at the University of Toronto, will give the 2020 Brosnan Lecture in Biochemistry on Nov. 24.

‘Exquisitely regulated’

“Insulin is the paramount anabolic hormone, promoting carbon energy deposition in the body,” said Dr. Klip. “It’s biosynthesis, quality control, delivery and action are exquisitely regulated by highly orchestrated mechanisms in different organs along its journey.”

During the lecture, she will first analyze insulin’s biosynthesis in and export from pancreatic β-cells.

Then, she will describe its first pass and partial clearance in the liver with its temporality and periodicity linked to secretion. Continuing the journey, Dr. Klip will briefly describe insulin’s action on the blood vasculature and its still-debated mechanism of exit from the capillary beds.

“Once in the parenchymal interstitium of muscle and adipose tissue, insulin promotes glucose uptake into myofibres and adipocytes,” she said. “I will elaborate on the intricate signalling and vesicle traffic mechanisms that enable this fundamental function. Cellular discernment of insulin’s availability and action should prove critical to understanding its pivotal physiological functions and how their failure leads to diabetes.”

Generous gift

The lecture is adapted from a paper Dr. Klip co-authored that was published in the Journal of Cell Biology.

For almost 40 years Dr. Klip has directed studies on insulin action at the cellular and molecular levels. She was the first to reveal the insulin- and exercise-dependent translocation of glucose transporters from inside the muscle to its surface.

Her group’s current work focuses on mechanisms that confer insulin resistance to muscle, including engagement of the innate immune system and on insulin and glucose interactions with microvascular cells.

The Brosnan Lecture in Biochemistry was established through a generous gift from Dr. Sean Brosnan.

An accomplished educator and one of Memorial’s premier scientists and researchers, his gift enables the Department of Biochemistry in the Faculty of Science to invite on an annual basis an eminent biochemist to deliver one or more lectures on biochemical research and/or on the history of biochemistry.

The second annual lecture takes place on Tuesday, Nov. 24, at 12 p.m. via Zoom.

Meeting information is available here.

All are welcome.