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David H St-Pierre, PhD
Professor of Kinanthropology
Biographical Sketch
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CIHR Post-Doctoral Fellow, Peptide Physiology and Endocrinology, U. Torino
(Molinette Hospital), Torino, Italy (E. Ghigo, F. Broglio; 2007-2010) and CRIUCPQ, U. Laval,
Quebec City (D. Richard, K. Cianflone; 2010-2011) |
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PhD Nutrition (CIHR Studentship), U. Montr�al (R. Rabasa-Lhoret; 2003-2006)
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MSc Biomedicine, U. Montr�al (2000-2002) |
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BSc Microbiology, McGill (1997-2000) |
Click here for pdf CV
Selected Scientific Contributions
1) St-Pierre DH, Wang L and Tach� Y. Ghrelin: a novel player in gut-brain
regulation of growth hormone and energy balance. NIPS 18:242-246, 2003.
I was among first to synthesize and to study ghrelin and related peptides in vivo. As a
consequence, I was invited by Dr Yvette Tach� (CURE, UCLA) to co-publish an early invited review in NIPS
to sum up known actions of the newly discovered peptide and hypothesize its putative physiological
functions. Until now, a number of those have been confirmed, including the influence of ghrelin on food
intake, adipogenesis and regulation of GH secretion.
2) St-Pierre DH et al. Hormonal profile associated with the insulin
sensitive overweight and obese subjects. Journal of Clinical Endocrinology and Metabolism 92:264-269,
2007.
I was part of a clinical team that carried out studies in insulin-sensitive (ISO) and insulin-resistant (IRO)
obese postmenopausal women, using euglycemic/ hyperinsulinemic (EHC) clamps. Unacylated and acylated ghrelin
(UAG, AG) profiles were analyzed during the EHC. I was able to establish that ISO women displayed a lower
AG/UAG ratio in the fasting condition and during the EHC. A significant decrease in AG in response to the
EHC was also observed in ISO but not in IRO women. This article provided the first evidence of specific AG
fluctuations in response to an hyperinsulinemic state in humans and reinforced the hypothesis that AG could
have a detrimental effect on insulin sensitivity.
3) Miegueu P, St-Pierre DH, Broglio F and Cianflone K. Effect of obestatin,
des-acyl ghrelin (dAG), acylated ghrelin and GHRP-6 in 3T3-L1 cell metabolism. J Cell Biochem
112:704-14, 2011.
Before leaving for PDF training in Italy in 2007, I was offered a short training in K. Cianflone�s (Canada
Research Chair on Adipose Tissue) lab to study the effects of GI peptides on adipocyte functions. I designed
and carried out a set of experiments using 3T3-L1 cells and, after I left for postdoctoral training in Turin,
the project was carried on by a PhD student (P. Miegueu) under my co-supervision. It was completed during the
year I spent as a PDF in Quebec City in 2010-2011. We also found that motilin, a peptide structurally related
to ghrelin, influences pre-, differentiating and mature adipocyte functions. Because this article sheds the
light on a so far unsuspected link between motilin, adipocyte functions and obesity, it was the object of a
flattering editorial comment (Ceddia R, Am J Physiol, 2011). This work was part of our series of articles
describing some of the effects of gastrointestinal peptides on the regulation of adipocyte functions.
Click here for PubMed listing
Research Interests
Areas of Research Interest
My primary research interests are in the integrative aspects of GI peptide physiology in organs and tissues
and how GI peptide-based interventions could optimally improve the health of individuals affected by obesity
and related insulin resistance, type 2 diabetes (T2D) and ensuing metabolic dysfunctions. My laboratory
focuses on better understanding basic mechanistic physiology using state-of-the-art techniques and methods
before designing novel interventions to try to modify disease state.
Ongoing Research Projects
The physiological role of gastrointestinal (GI) peptides in man is still largely unknown. I have had a
long-lasting interest in studying the role of GI peptides in the regulation of energy balance, especially
ghrelin since its discovery in 1999. Current projects going on in my laboratory aim two important features
of GI peptides, including the acylated (AG) and unacylated (UAG) forms of ghrelin, as well as motilin,
secretin and others, in health and disease:
1) GI peptides and energy balance. We study the influence of GI peptides on appetite and energy
expenditure in rodent models, using acute or chronic synthetic peptide administrations performed centrally or
peripherally in the animals. We also evaluate the combined effects of GI peptides and specific nutrients on
caloric intake. These studies provide critical information regarding food/water intake, energy expenditure and
physical activity over a prolonged period of time.
2) GI peptides and excessive lipid infiltration in organs and tissues. Lipid infiltration in organs
and tissues is suspected to be a key step in the development of metabolic dysfunctions but related mechanisms
remain to be elucidated. We study the influence and functional outcomes of GI peptides in the etiology of
excessive lipid infiltration in the liver and skeletal muscles using cell (primary and cell lines) and rodent
models. Lipid infiltration is evaluated by fluorescence microscopy and the identity of lipid species is
determined by mass spectrometry.
Opportunities for Graduate Student Training
My research facilities offer a unique training environment in peptide physiology, allowing students to explore
a wide breadth of basic as well as clinical research subjects of interest. I also interact with a number of
prominent research laboratories and clinical facilities located in Canada and abroad. These associations
facilitate training opportunities for graduate students and increase access to additional competences, staff,
measurement techniques, biological material and major equipment. I am currently considering applications from
highly motivated and outstanding PhD and postdoctoral trainees.
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