RESEARCH AREAS AND select PUBLICATIONS

Developmental Programming

A long-standing and important area of research for the lab has been examining the influence of parental environment (e.g., diet, housing, stress exposure) on programming of offspring stress responding. This began a number of years ago with the demonstration that exposure to predatory threat during the hours after a mom gives birth results in an increase in her caregiving to young. We have also investigated the long-lasting effects of prenatal stress in females and preconception stress in males on their offspring. As part of this work, we developed a semi-naturalistic housing environment for mom and her offspring as a way to ‘enhance’ the early environment and potentially alter or interact with the effects of prenatal or preconception stress of parents. This housing has profound effects on moms’ caregiving and ultimately the development of her offspring. This work was supported by an NSERC Discovery Grant and since 2016, much has been in collaboration with Dr. Ian Weaver at Dalhousie.

I also have an active collaboration with Dr. Jen Khoury at Mount Saint Vincent University (DPRC - Developmental Psychobiology Research Centre - MSVU (dpresearchcentre.com) in Halifax and we are presently co-supervising MSc students, Esther Puiras and Lauren Giles. This research investigates the long-lasting intergenerational consequences of child maltreatment that includes the importance of the prenatal and early postnatal periods. Recent estimates in Canada show that 34.1% adults experience some form of maltreatment before the age of 18 and thus it is essential to understand the impact of such maltreatment on newborn health outcomes and the diverse underlying biopsychosocial mechanisms. The goal of this work, funded by Research Nova Scotia is to elucidate these associations, in the perinatal period, as a critical first step to preventing long-term health effects for mothers and children.

Relevant Publications

Korgan, AC, Foxx, CL, Hashmi, H, Sago, SA, Stamper, CE, Heinze, JD, O’Leary, ME, King, JL, Perrot, TS, Lowry, CA, Weaver, ICG (2022). Effects of paternal high-fat diet and maternal rearing environment on the microbiota-gut-brain axis and behavior. Scientific Reports, 12(1):10179. doi: 10.1038/s41598-022-14095-z.

 Korgan, A, O’Leary, E, King, J, Weaver, I, Perrot, TS (2018) Effects of paternal high-fat diet and rearing environment on maternal investment and development of defensive responses in the offspring. Psychoneuroendocrinology, 91, 20-30.

Green, A, Esser, MJ, Perrot, TS (2018) Developmental expression of anxiety and depressive behaviours after prenatal predator exposure and early life home cage enhancement. Behavioural Brain Research, S0166-4328(17)31465-1.

Korgan, A, O’Leary, E, Bauer, J, Fortier, A, Weaver, ICG, Perrot, TS (2016) Effects of paternal predation risk and rearing environment on maternal investment and development of long-term defensive responses in the offspring. eNeuro, 3(6) e0231-16.2016, 1–14.

Korgan, A, Vonkeman, J, Esser, MJ, Perrot, TS (2015) An enhanced home cage modulates hypothalamic CRH-ir labeling in juvenile rats, with and without sub-threshold febrile convulsions. Developmental Psychobiology, 57(3), 374-81.

Korgan, A, Green, AD, Perrot, TS, Esser, MJ (2013) Limbic system activation is affected by prenatal predator exposure and postnatal environmental enrichment and further moderated by dam and sex. Behavioural Brain Research, 259C, 106-118.

Mashoodh, R, Sinal, CJ, Perrot-Sinal, TS (2009; Epub 2009 Jan 13) Predation threat exerts specific effects on rat maternal behaviour and anxiety-related behaviour of male and female offspring. Physiology & Behavior, 96, 693-702

Gut-Brain Connection

Our latest work, spearheaded by former PhD student, Libby Myles, and current PhD student, Elizabeth O'Leary, is concerned with unraveling the interactive effects of diet and probiotic exposure on development of offspring stress and metabolic outcomes. We have also expanded our work on early life development to look at the effects of probiotics and diet during pregnancy and lactation. These periods are crucial for offspring development, and there is emerging evidence that probiotics may reduce some of the adverse effects of unhealthy diets for both mother and offspring. Further to this is examining the effects of probiotics and diet during development and into adulthood. We are currently studying the impact of these factors in rats of both sexes to characterize how probiotic treatment and diet throughout life may influence the adult gut microbiome and associated health-related states. We are also investigating if and how probiotic supplementation can help mitigate the effects of acute stress exposure on aspects of cognitive function in humans. All research related to the gut-brain connection is in collaboration with the Rosell® Institute for Microbiome and Probiotics at Lallemand Health Solutions (Rosell Institute (rosellinstitutelallemand.com) and has been supported by NSERC Engage Grants and Mitacs funding.

I have an active collaboration with Dr. Heather Neyedli in the Faculty of Health at Dalhousie and we are presently co-supervising PhD student, Cory Munroe. One research project investigates the interaction of stress and exercise on cognitive function and is funded by a Development & Innovation grant from Research Nova Scotia. A second exciting research project is in collaboration with Lallemand Health Solutions and involves a Health Canada approved randomized, double-blind placebo-controlled clinical trial to investigate the effects of probiotics on cognition and related outcomes among video gamers. Stay tuned!!

Relevant Publications

Myles, EM, Hamm, SI, Allden, SN, Romkey, ID, O’Leary, ME, Perrot, TS (2022) A comparative study of Western, high-carbohydrate, and standard lab diet consumption throughout adolescence on metabolic- and anxiety-related outcomes in young adult male and female Long Evans rats. Behavioural Brain Research, 438; 114184 (https://doi.org/10.1016/j.bbr.2022.114184)

Munroe, CA, Gonzalez, BC, Tompkins, TA, Neyedli, HF, Perrot, TS (September 2021) Investigating the effect of probiotic supplementation on cognition and related health outcomes among video gamers: Background and protocol. Presentation at the Atlantic Mobility Action Project Meeting.

Myles, EM, O’Leary, ME, Smith, R, MacPherson, CW, Oprea, A, Melanson, EH, Thompkins, TA, Perrot, TS. (2020) Supplementation with combined Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 across development reveals sex differences in physiological and behavioural effects of Western diet in Long-Evans rats. Microorganisms, 8(10), 1527 (doi: 10.3390/microorganisms8101527)