The global population is aging rapidly. This demographic shift towards an older population poses a major public health challenge and highlights the need to identify strategies to support healthy aging. Prior research has suggested that green space may promote cognitive health, but there are gaps in knowledge that limit the application of findings in planning and policy to optimize health benefits. In this work, we will use long-term data on aging to study the influence of residential green space exposure on cognitive decline and dementia among middle-aged and older adults. We will advance existing knowledge by studying the health impacts of specific green space types and forms of contact, as well as pathways linking green space to health outcomes. We will use these findings to develop and apply an index of green space characteristics that are supportive of healthy cognitive aging that may be used by urban planners to direct the design of greening strategies. We will communicate our research findings to scientists, policy makers, and the public. Our aim is to help guide the creation of urban planning and public health policies that improve population health. This work will help to advance initiatives to support healthy aging.
Program: Trainee
Advancing Cardiovascular Research: Developing Vascularized Heart Organoids-on-Chips Integrating Immume Cells
Organoids, miniature organ models grown from stem cells, replicate the complexity of actual organs on a scale of about one millimeter. They exhibit similar morphology and functions but lack crucial elements like vasculature and immune response. In contrast, organs-on-chips, while providing dynamic microenvironments, typically use less sophisticated biological models. By combining these technologies, we can leverage the biological accuracy of organoids with the dynamic capabilities of organs-on-chips. This synergy aims to replicate in vivo physiology, enabling a more accurate study of disease characteristics and drug responses.
The project’s centerpiece is to engineer heart organoids-on-chips, with functional vascular and immune components, to investigate hypertrophic cardiomyopathy (HCM). We will evaluate the efficacy of drugs in mitigating hypertrophic responses. In addition, the study will include perfusion of immune cells to analyze the role of inflammation in HCM progression, investigating immune cell recruitment.
This initiative coincides with the U.S. FDA’s pivot from mandatory animal testing for new drugs, marking a significant shift towards more relevant human-based models in drug development.
Cerebrovascular physiology of circulatory death in patients undergoing medical assistance in dying (MAiD)
Patients undergoing medical assistance in dying (MAiD) can qualify as organ donors. Donation commences after death, which is declared when blood pressure drops below a certain threshold. We believe that a low enough blood pressure means the brain is no longer receiving blood, which represents true death, after which donation can begin. The time it takes for blood pressure to become low enough (ischemic time) can cause damage to organs because of reduced blood flow. If it takes too long for blood pressure to reach the threshold, too much damage occurs, and organs are discarded. The threshold value of blood pressure is based on studies of critically ill patients in the intensive care unit. We are not sure if the same thresholds would apply to patients undergoing MAiD, as their underlying physiology is different. We think the threshold would be higher for patients undergoing MAiD. We will measure blood flow velocity to the brain in patients undergoing MAiD using transcranial doppler. If blood flow stops at higher blood pressure levels than currently used cutoffs, this would reduce ischemic time and reduce damage to potential donated organs. We will report our results in scientific journals and through organ donation organizations.
Addressing inter-individual variability in aging: linking lifestyle factors to the brain and behaviour
Cognitive decline is associated with a variety of neurodegenerative disorders and is increasingly prevalent in Canada’s aging population. One of the most effective means to counteract cognitive decline is to maintain or enhance cognitive reserve. Lifestyle factors have been shown to impact cognitive reserve, but this impact varies highly across individuals. Most investigations into the effects of lifestyle factors on behavior and neural function do not capture this inter-individual variability and produced mixed, difficult to reproduce findings. This research aims to reduce this variability by clustering the population into sub-types based on their susceptibility to lifestyle changes before investigating the causal relationships between lifestyle factors, behaviour and neural function. The identified causal relationships will serve as promising targets for future clinical interventions in sub-types of our aging population that can limit the effects of cognitive decline and lower the rates of neurodegenerative diseases. In addition to the classical means of knowledge translation, this research will be shared through public presentations held by the Institute of Neuroscience and Neurotechnology at Simon Fraser University.
Structure-function relationship of retinal guanylyl cyclase, a key enzyme in phototransduction
Light adaptation is the ability of visual system to adjust its performance to the ambient level of illumination. It is fundamentally vital for the normal functioning of the visual system. During the normal cycle of day and night, the illumination of the earth’s surface varies over 11 orders of magnitude. The daily cycle of sensitivity adjustment is managed by switching between rod and cone pathways of retina. These pathways involve retinal guanylyl cyclase (retGC), an enzyme encoded by the GUCY2D gene expressed in rod and cone photoreceptors. In the light-induced signal cascade, retGC restores cGMP levels in the dark in a calcium-dependent manner. Mutations in GUCY2D are associated with recessive Leber congenital amaurosis-1 (LCA1) as well as dominant and recessive forms of cone-rod dystrophy (CORD). Presently, the molecular structure of retinal GC has not been determined; thus, its mechanism, interaction with other regulators, and identity of crucial residues conferring the activity of this enzyme have been elusive. We aim to fill this gap in our knowledge by determining the molecular structure of retGC. This information will enhance our understanding of the role of retGC in photoreceptors and diseases.
Caregiver-Child Sleep and Relationships in Canadian Foster and Kinship Families
Sleep is important for health, yet little is known about sleep in foster and kinship families. In my postdoctoral fellowship, I will lead research to learn about the sleep health, how best to support sleep, and the connection between sleep and caregiver-child relationships for foster/kinship families. In Study 1, we will synthesize research on children’s sleep in foster and kinship care. In Study 2, we will interview foster and kinship caregivers of children aged 0-5 years to learn about the caregiver and child’s sleep, and how sleep influences the caregiver-child relationship. In Study 3, we will compare sleep in foster and kinship families with other families in Canada. In Study 4, foster and kinship caregivers will help us design and test a sleep resource. We are creating an advisory panel to work with us to create research that is useful and interesting to the foster/kinship community, and respectful of different cultures and family dynamics. With the advisory panel, we will share the results in journal articles, at conferences, via webinars, and through foster/kinship organizations. This research will help healthcare professionals and policymakers understand, and help support, the sleep of families in foster and kinship care.
Co-creation of culturally-safe drug checking practices for Indigenous Peoples who use illicit drugs
Indigenous Peoples who use illicit drugs (IPWUID) are disproportionately affected by the drug poisoning crisis. Community-wide drug checking is a potential response to address the problem. Previous research has explored how best to implement drug checking as a response to overdose, as well as how to better include people who use drugs (PWUD) within drug-checking. However, Indigenous Peoples are not well represented in this research and Indigenous research approaches have not yet been undertaken. This study uses Indigenous research methods to better understand the needs and perspectives of IPWUID in accessing new drug checking technologies and services. It also explores the gaps in drug checking services for IPWUID in British Columbia (BC) and examines how unmet drug checking needs may affect their health outcomes. The outcome will be an Indigenous Harm Reduction approach to drug checking to inform new models and knowledge production approaches that best meet the needs of IPWUID.
Consequences of preconception bariatric surgery for fetal size and pathological growth restriction: a linked population registry study.
In Canada, 20-30% of reproductive-aged women suffer from obesity, which increases the chances that they will experience pregnancy complications. Preconception treatment of obesity with bariatric surgery reduces the risks of most pregnancy complications, but it increases the risk of having a baby measured in the smallest 10% (small-for-gestational-age, SGA). However, SGA is a poor indicator of fetal growth restriction (FGR), a condition where growth is impeded by a disease process. This distinction is important as FGR is associated with increased risks of neonatal complications, while most SGA infants are healthy. Whether preconception treatment with bariatric surgery is associated with increased odds of FGR is still unclear.
In this study, we will use a population database to evaluate the association between preconception bariatric surgery and the risk of FGR. Results of this study will be important to examine the balance between risks and benefits of preconception bariatric surgery in clinical care. Results will be diffused through scientific publications and presentations. Educational material, including infographic summaries and courses, will be created to disseminate findings to clinicians and patients.
SuPA Mobility: Supporting Physical Activity for Mobility in Older Adults with Mobility Limitations
Problem
As individuals age, they have a greater risk of limited mobility, or difficulty in getting around safely in one’s environment. Limited mobility is linked to illness, disease, and decreased quality of life.
Recent research show increasing physical activity by 6-minutes per day can improve mobility and prevent future disability. Despite the positive impacts on health, many older Canadians do not perform sufficient physical activity. Health coaching, a person-centered process to change behaviors with goal-setting, action planning, and feedback, is effective at improving physical activity participation in older adults. However, none of the previous health coaching studies included older adults with limited mobility.
Research
This study aims to address this knowledge gap to evaluate if health coaching can improve mobility and increase physical activity in older adults with limited mobility. We will conduct a 6-month study comparing health coaching to health education on improving mobility in older adults aged with limited mobility.
Potential Impact
Increasing physical activity through the use of health coaching has the potential to improve mobility and decrease the negative health impacts of limited mobility in older adults.
Uncovering metabolic mechanisms for tumor-driven immunosuppression with mass spectrometry imaging
Scientists have uncovered ways to turn the body’s natural immune system against cancer – an approach termed immunotherapy. While highly effective for some patients and cancer types, many patients do not respond. This creates a fundamental knowledge gap: why do only certain patients respond to immunotherapies? The answer may lie in the adage – “you are what you eat”. Cancers, at the cellular level, consume lots of fats, sugars, and 1000’s of other molecules collectively termed ‘the metabolome’. This leads to immune cells needing to fight for key fuels, and tumor cell production of toxic by-products which can kill natural immune cells. Together, this can incapacitate the immune system and may be why immunotherapies fail. Resolving this metabolic hurdle will require emerging, state-of-the-art technologies that can distinguish cancer cell metabolism and immune cell metabolism as they exist in the tissue (i.e. with their spatial distribution preserved). This project aims to develop and apply cutting-edge technologies to profile tumors which are responsive & unresponsive to immunotherapy, providing a fundamental understanding of tumor metabolism and allowing us to identify new opportunities to improve targeted immunotherapy treatments.