Alfonso Abizaid

Degrees:Ph.D. (Concordia)
Phone:613-520-2600 x 1544
Email:alfonso.abizaidbucio@carleton.ca
Office:329 Life Sciences Research Building
Website:Website

Eligible to supervise at the undergraduate and graduate level.

Current research in the Abizaid Lab:

  • Predominant focus is on the hormone ghrelin and how it modulates feeding, metabolism, stress, and circadian rhythms. Conducting research to elucidate how this hormone activates components of the mesolimbic dopamine system and what other systems it interacts with (e.g. endocannabinoid system) to enhance motivation and reward seeking behaviours (feeding, sex, etc.)
  • Discovering how early life developmental conditions impact the development of many adverse metabolic conditions (obesity, type 2 diabetes, metabolic syndrome, etc). For example, how early life exposure to synthetic compounds such as bisphenol-A (BPA) interferes with the development of hypothalamic circuitry involved in regulating food intake and energy expenditure.
  • Studying the role that ghrelin plays in modifying feeding and metabolism in pregnant female rats and how this affects the reproductive outcome.

Click here to read about Stress and Obesity: The Ghrelin Connection

Area of Research

Neuroendocrine Modulation of Appetitive Behaviors

In general I am interested in the way the brain integrates sensory and hormonal information to modulate feeding, reproduction and activity rhythms. One of my main interests resides in the way peripheral signals known to regulate energy balance like ghrelin and leptin modulate behaviors not only related to homeostatic regulation, but also higher order processes like motivation, emotion, and learning. I am currently working on a project where I have determined how peripheral signals like ghrelin modulate the activity of brain circuits associated with motivated behaviors. Some of the questions that I am asking in my program are: Does peripheral ghrelin reach reward circuits? Does peripheral ghrelin modulate the activity of cells in these circuits? Can ghrelin modulate reward-seeking behaviors? Are effects of ghrelin on reward circuits associated selectively to food, or do they generalize to other rewarding stimuli? Are dysfunctions in these systems associated with abnormal feeding behaviors and obesity? I believe that answers to these questions will ultimately lead to novel treatment avenues for decreasing food cravings and perhaps cravings for drugs of abuse.

Hormonal Regulation of circadian rhythms

I am also interested in the hormonal regulation of circadian behavior. Interestingly receptors for metabolic signals like ghrelin, leptin and estrogen are also found in hypothalamic centers associated with circadian rhythmicity, suggesting that these signals could potentially play a role in the regulation of daily or seasonal patterns of behavior, and endocrine function.

Aging and hypothalamic regulation

Finally, disruptions in hypothalamic centers underlying circadian rhythms produced by ageing may represent the etiology for a variety of pathological conditions that include obesity, menopause, depression, and sleep disorders. The impact of metabolic hormones, and ageing on the circadian system are also the focus of my current projects. A better understanding of how changes in these hormones during ageing affect cells in the circadian system will lead to treatments that maintain biological and behavioral rhythms functioning optimally for a longer period of time.

Recent Publications

Mackay, H, Charbonneau, VR, St. Onge, V, Murray, E, Watts, A, Wellman, MK, & Abizaid, A. (2016). Rats with a ghrelin receptor (GHSR) null mutation do not respond to ghrelin, and show reduced intake of palatable, high-calorie food. Manuscript accepted, Physiology and Behavior, DOI: 10.1016/j.physbeh.2016.04.048

Edwards, A. & Abizaid, A. (2016). Driving the need to feed: Insight into the collaborative interaction between ghrelin and endocannabinoid systems in modulating brain reward systems. Manuscript accepted in Neuroscience and Biobehavioral Reviews.

St-Onge, V, Watts, A, and Abizaid, A. (2016). Ghrelin enhances cue-induced bar pressing for high fat food. Hormones and behavior 78, 141-149.

King, SJ, Rodrigues, T, Watts, A, Murray, E, and Abizaid, A. (2016) Investigation of a Role for Ghrelin Signaling in Binge-Like Feeding in Mice Under Limited Access to High-Fat Diet

Agil, R., Patterson, ZR, Mackay, H, Abizaid, A., and Hosseinian, F. (2016). Triticale Bran Alkylresorcinols Enhance Resistance to Oxidative Stress in Mice Fed a High-Fat Diet Foods 5 (1), 5

Wellman, M.K., Patterson, Z.R., MacKay, H., Darling, J.E., Mani, B.K. Zigman, J.M, Hougland, J.L. & Abizaid, A. (2015). Novel regulator of acylated ghrelin, CF801, reduces weight gain, rebound feeding after a fast, and adiposity in mice. Frontiers in Systems and Translational Endocrinology, http://dx.doi.org/10.3389/fendo.2015.00144.

Wellman, M.K., and Abizaid, A. (2015) Knockdown of central ghrelin O-acyltransferase by vivo-morpholino reduces body mass of rats fed a high-fat diet. Peptides, 70:17-22

Wellman, M.K., & Abizaid, A. (2015). Growth Hormone Secretagogue Receptor Dimers: A New Pharmacological Target. E-neuro 2 (2), ENEURO. 0053-14.2015

Marmolejo-Ramos, F., Hellemans, K., Comeau, A., Heenan, A., Faulkner, A., Abizaid, A. & and D’Angiulli, A. (2015) ERP signatures to perceived and imagined emotional and real-life photos. Neuroscience Bulletin, In Press.

MacKay, H. & Abizaid, A. (2014). Embryonic development of the hypothalamic feeding circuitry: Transcriptional, nutritional, and hormonal influences. Molecular Metabolism, 3, 813-822.

Abizaid, A. & Anisman, H. (2014) Gut feelings about depression. Journal of Psychiatry & Neuroscience: JPN 39 (6), 364-366.

Lee CY, Abizaid A.(2014) The gut-brain-axis as a target to treat stress-induced obesity. Frontiers in Endocrinology (Lausanne). 2014 Jul 18;5:117.

McQuaid RJ, McInnis OA, Abizaid A, Anisman H. (2014) Making room for oxytocin in understanding depression. Neuroscience & Biobehavioral  Reviews. 2014 Sep;45C:305-322

Patton, D.F, Katsuyama, A. M., Pavlovski, I., Michalik, M., Patterson, Z.R., Parfyonov, M., Smit, A.N.,  Marchant, E.G., Chung, J., Abizaid, A., Storch, K-F., de la Iglesia, H., and Mistlberger, R.E. (2014) Circadian Mechanisms of Food Anticipatory Rhythms in Rats Fed Once or Twice Daily: Clock Gene and Endocrine Correlates. PloS One, 9 (12), e112451. DOI: 10.1371/journal.pone.0112451

Jodayree, S., Patterson, Z.R., MacKay, H., Abizaid, A. & Tsopmo, A. (2014) Blood and Liver Antioxidant Capacity of Mice Fed High Fat Diet Supplemented with Digested Oat Bran Proteins. International Journal of Food Science and Nutrition Engineering 4 (1), 9-14.

Cahill, S.P., Hatchard, T., Abizaid, A. & Holahan, M.R. (2014) An examination of early neural and cognitive alterations in hippocampal-spatial function of ghrelin receptor-deficient rats. Behavioral Brain Research, 264(1), 105-115.
Raspopow, K., Abizaid, A., Matheson, K., Anisman, H. (2014) Anticipation of a psychosocial stressor differentially influences ghrelin, cortisol and food intake among emotional and non-emotional eaters. Appetite, 74(1):35-43.

Lamont, EW, Bruton, J., Blum, ID., and Abizaid, A. (2013) Ghrelin receptor knockout mice display alterations in circadian rhythms of activity and feeding under constant lighting conditions. European Journal of Neuroscience, doi: 10.1111/ejn.12390.

Patterson, Z.R., Parno T.J., Isaacs A.M. and Abizaid, A. (2013) Interruption of ghrelin signaling in the PVN increases high-fat diet intake and body weight in stressed and non-stressed C57BL6J male mice. Frontiers in Neuroendocrine Science, doi: 10.3389/fnins.2013.00167.
Patterson, Z.R., and Abizaid, A. (2013) Stress-Induced obesity: Lessons learned from rodent models of stress. Frontiers in Neuroendocrine Science, Doi: 10.3389/fnins.2013.00130.

MacKay, H., Khazall, R., Patterson, Z.R., Wellman, M.K., and Abizaid A. (2013) Rats perinatally exposed to food restriction and high-fat diet show differences in adipose tissue gene expression under chronic caloric restriction. Adipocyte, 2(4).
MacKay, H., Patterson, Z.R., Khazall, R., Patel, S., Tsirlin, D. and Abizaid A. (2013) Organizational Effects of Perinatal Exposure to Bisphenol-A and Diethylstilbestrol on Arcuate Nucleus Circuitry Controlling Food Intake and Energy Expenditure in Male and Female CD-1 Mice. Endocrinology April 1, 2013 vol. 154 no. 4 1465-1475.
Patterson, Z.R., MacKay, H., Khazall, R., Anisman, H. and Abizaid, A. (2013) Central Ghrelin Signaling Mediates the Metabolic Response of C57BL/6 Male Mice to Chronic Social Defeat Stress. Endocrinology March 1, 2013vol. 154 no. 3 1080-1091
Raspopow, K., Abizaid, A., Matheson, K., Anisman, H. (2013). Unsupportive social interactions influence emotional eating behaviors. The role of coping styles as mediators. Appetite,Vol 62, 1 March 2013, Pages 143–149.

Abizaid, A. and Horvath, T.L. (2012) Ghrelin and the central regulation of feeding and energy balance. Indian Journal of Endocrinology and Metabolism, 16 (9), 617-626.

Woodside, B,  Budin, R., Wellman, M. K., & Abizaid, A. (2012). Many mouths to feed: The control of food intake during lactation. Frontiers in Neuroendocrinology, Manuscript Accepted.