Check out some of the papers that were recently published by DMCBH members:

 

Robin Hsiung: Gene-Specific Effects on Brain Volume and Cognition of TMEM106B in Frontotemporal Lobar Degeneration 

Journal: Neurology  

Frontotemporal lobar degeneration (FTLD) results from losing frontal and anterior temporal lobes.  This is one of the leading causes of dementia, and it is associated with a variant of the gene TMEM106B. The major allele is associated with an increased risk of FTLD, particularly in GRN pathogenic variant carriers. The present study evaluated and compared the effect of TMEM106B on grey matter volume and cognition in patients with genetic and sporadic frontotemporal dementia (FTD). The minor allele of TMEM106B, linked with a decreased risk of FTD, was associated with greater gray matter volume in GRN variant carriers. This effect was most pronounced in the left hemisphere thalamus. The minor allele was also associated with greater cognitive scores. In the development of gene-based therapies, it is important to consider TMEM106B’s genetic status in account of clinical trial design and recruitment.  

 

Paul van Donkelaar: The Association Between Teen Dating Violence and Concussion 

Journal: Journal of Adolescent Health  

Intimate partner violence and traumatic brain injuries are commonly associated in adults, but there is little research on this association in youth. This study explored the association between teen dating violence (TDV) and concussion to inform clinical care. This study used data from ninth and tenth-grade youth from a nationally representative Canadian dataset. TDV in the past year was measured using three items for victimization and three for perpetration. Youth were also asked if they were medically informed about having a concussion in the past year, and what the context was behind the concussion. TDV was related to higher odds of concussion, both overall and when controlled for non-sport settings. Youth with mutual TDV reported the highest rates of concussion in the past year and girls and nonbinary youth were at higher risk. Findings can be used to inform future research and may assist health providers.  

 

Raymond Lam: Endocannabinoid concentrations in major depression: effects of childhood maltreatment and relation to hippocampal volume 

Journal: Translational psychiatry  

Major depressive disorder (MDD) is the leading cause of disability worldwide, and research has established a causal link between stress and MDD. Smaller hippocampal volume is strongly implicated as a potential biomarker of stress-related pathophysiology in MDD. Stress-related reductions in hippocampal volume may be impacted by regulation from the endocannabinoid system (eCB). This system is a strong stress buffer with ligands like anandamide and may protect against hippocampal volume reduction. However, stress could also lead to dysregulation of this system. Therefore, pathways from stress such as childhood maltreatment (CM) to hippocampal shrinkage may depend on the function of the eCB system. The present study examined whether the relationship between MDD and eCB concentrations would vary as a function of CM, and if eCBs moderate the relation of MDD/CM and hippocampal volume. Results indicated that MDD was associated with eCBs, but not all associations were moderated by CM. Lower left hippocampal volume was found in participants with CM compared to those without CM, but only for those with lower anandamide levels. This study presents the first evidence in humans that eCBs can affect stress-related mechanisms involving reduced hippocampal volume in MDD.  

 

Blair Leavitt: Elevated plasma and CSF neurofilament light chain concentrations are stabilized in response to mutant huntingtin lowering in the brains of Huntington’s disease mice 

Journal: Translational Neurodegeneration  

Therapeutic approaches aimed at lowering toxic mutant huntingtin protein levels in the brain can reverse Huntington’s disease (HD) phenotypes in animal models. Sensitive and dynamic biomarkers are needed to assess the efficacy of therapies like this. One candidate is neurofilament light chain (NfL) which increases in cerebrospinal fluid (CSF) and blood as HD progresses. Longitudinal plasma and cross-sectional CSF samples were collected from a transgenic mouse model, and biofluids were collected after administration of a drug targeting the mutant gene before and after disease symptoms appeared. NfL levels were significantly higher in the transgenic mice from 9 months of age. The drug reduced the expression of the harmful gene, especially when given early. Early treatment lowered NfL in spinal fluid but not in blood. After symptoms appeared, the drug led to dose-dependent stabilization of NfL levels in both. This paper provided evidence that the response of NfL in biofluids is influenced by how much the harmful gene is reduced in the brain as well as the timing of intervention. NfL may be a promising exploratory response biomarker for HD.  

 

Lara Boyd, Janet Werker, Sarah Kraeutner: Musical Sophistication and Multilingualism: Effects on Arcuate Fasciculus Characteristics 

Journal: Human Brain Mapping  

The arcuate fasciculus is a fibre tract inside of the brain which connects the temporal cortex to the inferior frontal gyrus. It is primarily involved with the processing of auditory stimuli, and past research has indicated the effects of musical and language experience on the structural characteristics of the arcuate fasciculus. To determine the effects of these experiences, the brains of 84 young adults with various degrees of musical and multilingual experience were examined with diffusion tensor imaging. Probabilistic tractography was used to identify dorsal and ventral parts of tracts.  It was found that different aspects of musical sophistication related to the volume, asymmetry and fractional anisotropy of the arcuate fasciculus. Meanwhile, multilingual experience was not found to be linked to the structural characteristics of the arcuate fasciculus.  

 

Will Panenka, Noah Silverberg, Donna Lang, Cheryl Wellington, Jon Stoessl, Mypinder Sekhon, Vesna Sossi: Differences in brain structure and cognitive performance between patients with long-COVID and those with normal recovery 

Journal: Neuroimage 

The pathophysiology of long COVID is not yet clear. This study aimed to determine if long COVID is associated with differences in baseline characteristics, markers of white matter diffusivity and lower scores on objective cognitive testing. Individuals who experienced symptoms for more than 60 days post-infection were compared to those who had a normal recovery. Magnetic resonance imaging and diffusion tensor imaging were used to examine their brains, and cognitive scores were taken. The long COVID group had significantly lower mean diffusivity than the normal recovery group across multiple white matter regions and cognitive scores did not differ significantly. Pathological inference of long COVID is difficult given the small effect sizes and non-specific nature of the diffusion indices.  

 

Khaled Abdelrahman: Minor Cannabinoids as an Emerging Frontier for Pain Relief 

Journal: The Journal of Pharmacology and Experimental Therapeutics 

This research article discusses the findings of a recent paper by Schwarz and colleagues (2024), which explored the impact of five minor cannabinoids on behaviour and physiology. The results revealed a range of effects from these previously overlooked cannabinoids and highlighted sex-specific differences. This article summarizes the key insights from the study and offers recommendations for future research in this area.