Sanoji Wijenayake

• PhD
• Professor (Assistant) at University of Winnipeg

Maternal consumption of a high-fat diet (mHFD) during perinatal life (the collective prenatal and postnatal periods) influences neonatal development, initiates hypothalamic-pituitary-adrenal (HPA) axis activation, and impacts the long-term physiological and metabolic health of offspring. Milk-derived extracellular vesicles (MEVs) are lipid-coated n...

Proteotoxic stress induces microglia polarization and attenuates cytoprotective, pro-survival cellular cascades. Milk-derived extracellular vesicles (MEVs) are lipid-coated nanovesicles that combat pro-inflammation in peripheral cells and tissues; however, the cytoprotective potential of MEVs remains unknown in brain macrophages. We investigated wh...

Mammalian milk contains milk-derived extracellular vesicles (MEVs), a group of biological nanovesicles that transport macromolecules. Their ability to cross the blood brain barrier and the presence of cargo capable of modifying gene function have led to the hypothesis that MEVs may play a role in brain function and development. Here, we investigate...

Lactation is a critical time in mammalian development, where maternal factors shape offspring outcomes. In this scoping review, we discuss current literature concerning maternal factors that influence lactation biology and highlight important associations between changes in milk composition and offspring outcomes. Specifically, we explore maternal...

Background The discovery of humanin (HN/MTRNR2) 20 years ago blazed a trail to identifying mitochondrial derived peptides with biological function. Scope Humanin is associated with pro-survival, cytoprotective, anti-inflammatory, and anti-oxidative properties and may play a role in reducing neurodegenerative and metabolic disease progression. Alth...

Milk is a highly complex, heterogeneous biological fluid that contains non-nutritive, bioactive extracellular vesicles called exosomes. Characterization of milk-derived exosomes (MDEs) is challenging due to the lack of standardized methods that are currently being used for milk pre-processing, storage, and exosome isolation. In this study, we teste...

The perinatal period is a sensitive time in mammalian development that can have long-lasting consequences on offspring phenotype via maternal effects. Maternal effects have been most intensively studied with respect to two major conditions: maternal diet and maternal stress. In this review, we shift the focus by discussing five major additional mat...

Mitochondria was long thought to be an “end function” organelle that regulated the metabolic flux and apoptosis in the cell. However, with the discovery of the mitochondrial peptide (MDP) humanin (HN/MTRNR2), the cytoprotective and pro-survival applications of MDPs have taken the forefront of therapeutic and diagnostic research. However, the regula...

Trachemys scripta elegans can survive up to three months of absolute anoxia at 3 °C and recover with minimal cellular damage. Red-eared sliders employ various physiological and biochemical adaptations to survive anoxia with metabolic rate depression (MRD) being the most prominent adaptation. MRD is mediated by epigenetic, transcriptional, post-tran...

Adverse maternal diets high in saturated fats are associated with impaired neurodevelopment and epigenetic modifications in offspring. Maternal milk, the primary source of early life nutrition in mammals, contains lactation-specific microRNAs (miRNAs). Lactation-specific miRNAs have been found in various offspring tissues in early life, including t...

Milk is a highly complex, heterogeneous biological fluid that contains bioactive, membrane-bound extracellular vesicles called exosomes. Characterization of milk-derived exosomes (MDEs) is challenging due to the lack of standardized methods that are currently being used for milk pre-processing, exosome isolation, and RNA extraction. In this study,...

Hibernators have evolved effective mechanisms to overcome the challenges of torpor-arousal cycling. This study focuses on the antioxidant and inflammatory defenses under the control of the redox-sensitive and inflammatory-centered NFκB transcription factor in the thirteen-lined ground squirrel (Ictidomys tridecemlineatus), a well-established model...

Background: Maternal obesity as a result of high levels of saturated fat (HFD) consumption leads to significant negative health outcomes in both mother and exposed offspring. Offspring exposed to maternal HFD show sex-specific alterations in metabolic, behavioral, and endocrine function, as well as increased levels of basal neuroinflammation that...

Background Acute elevations in endogenous corticosterone (CORT) with psychosocial stress or exogenous administration potentiate inflammatory gene expression. Maternal obesity as a result of high-fat diet (HFD) consumption has been linked to higher basal levels of neuroinflammation, including increased expression of pro-inflammatory genes in the amy...

Wood frogs, Rana sylvatica, can undergo prolonged periods of whole body freezing during winter, locking as much as 65–70% of total body water into extracellular ice and imposing both anoxia and dehydration on their cells. Metabolic rate depression (MRD) is an adaptation used by R. sylvatica to survive these environmental stresses, where a finite am...

The importance of histone lysine methylation is well established in health, disease, early development, aging, and cancer related-research. However, the potential role of epigenetics in regulating gene expression in response to extended periods of oxygen deprivation (anoxia) in a natural anoxia-tolerant model system is underexplored. Red-eared slid...

Mammalian hibernation is characterized by extensive adjustments to metabolism that typically include suppression of carbohydrate catabolism and a switch to triglycerides as the primary fuel during torpor. A crucial locus of control in this process is the pyruvate dehydrogenase complex that gates carbohydrate entry into the tricarboxylic acid cycle....

When faced with harsh environmental conditions, the South American marsupial, monito del monte (Dromiciops gliroides), reduces its body temperature and uses either daily torpor or multiday hibernation to survive. This study used ELISA and multiplex assays to characterize the responses to hibernation by three regulatory components of protein transla...

Hibernation is a period of torpor and heterothermy that is typically associated with a strong reduction in metabolic rate, global suppression of transcription and translation, and upregulation of various genes/proteins that are central to the cellular stress response such as protein kinases, antioxidants, and heat shock proteins. The current study...

The South American marsupial, monito del monte (Dromiciops gliroides) uses both daily torpor and multi-day hibernation to survive in its southern Chile native environment. The present study leverages multiplex technology to assess the contributions of key stress-inducible cell cycle regulators and heat shock proteins to hibernation in liver, heart,...

Background: The thirteen-lined ground squirrel (I. tridecemlineatus) becomes hypometabolic during hibernation; characterized by reductions in energy expensive processes like transcription during periods of low temperature and starvation. We were interested in elucidating the mechanisms of transcriptional control by studying the MAPK pathway and do...

African clawed frogs (Xenopus laevis) endure bouts of severe drought in their natural habitats and survive the loss of approximately 30% of total body water due to dehydration. To investigate molecular mechanisms employed by X. laevis during periods of dehydration, the heat shock protein response, a vital component of the cytoprotective stress resp...

Pyruvate dehydrogenase (PDH) is a vital regulatory enzyme that catalyzes the conversion of pyruvate into acetyl-CoA and connects anaerobic glycolysis to aerobic TCA cycle. Post-translational inhibition of PDH activity via three serine phosphorylation sites (pS232, pS293, and pS300) regulate the metabolic flux through the TCA cycle, decrease glucose...

As a result of suppressed recombination, heterogametic sex chromosomes (either Y or W) are usually assumed to gradually shorten over evolutionary time as a way to remove accumulated mutations. However, suppressed recombination removes the most obvious mechanism for excising portions of sex chromosomes. We examined ratios of W/Z chromosome size acro...

Oxygen deprivation is a lethal stress that only a few animals can tolerate for extended periods. This study focuses on analyzing the role of DNA methylation in aiding natural anoxia tolerance in a champion vertebrate anaerobe, the red-eared slider turtle (Trachemys scripta elegans). We examined the relative expression and total enzymatic activity o...

The common wood frog, Rana sylvatica , utilizes freeze tolerance as a means of winter survival. Concealed beneath a layer of leaf litter and blanketed by snow, these frogs withstand subzero temperatures by allowing approximately 65–70% of total body water to freeze. Freezing is generally considered to be an ischemic event in which the blood oxygen...