Biology subjects

McConnell, B.

Publications and source records attributed to McConnell, B..

3 recordsLinked to original sources

bioRxiv2026

Overexpression of miR-424(322)/-503 induces severe dilated cardiomyopathy by regulating the fatty acid oxidation gene expression program

Fatty acid oxidation (FAO) is a major energy source in the adult heart, and disruption of cardiac metabolism is closely associated with heart failure. Here, we investigated the effects of cardiac-specific overexpression of the H19X-encoded miR-424(322)/-503 cluster using an inducible transgenic mouse model. Sustained miR-424(322)/-503 overexpression caused rapid metabolic and functional deterioration, with early impairment of fatty acid oxidation. Short-term induction reduced FAO activity and downregulated genes involved in lipid metabolism, while glycolytic enzyme activity remained largely unchanged. Continued miR-424(322)/-503 expression subsequently led to severe dilated cardiomyopathy characterized by ventricular dilation, wall thinning, fibrosis, reduced contractility, and high mortality. Importantly, disease progression was dependent on the level and duration of miR-424(322)/-503 expression, as intermittent or lower-dose induction delayed cardiac dysfunction and prolonged survival. Withdrawal of miR-424(322)/-503 expression after the onset of dysfunction promoted substantial functional recovery. Together, these findings identify miR-424(322)/-503 as a potent regulator of cardiac metabolic reprogramming that disrupts fatty acid metabolism and drives progressive heart failure.

molecular biology↗

bioRxiv2025

Comparing Vibrotactile Stimulation to Combined Visual and Auditory Stimulation for 40 Hz Gamma Entrainment

There is significant interest in combined visual and auditory stimulation to entrain 40 Hz gamma oscillations for the treatment of Alzheimers disease and other neurological conditions such as stroke and insomnia. In this work, we compared another sensory modality--vibrotactile stimulation delivered with a glove--to visual and auditory stimulation in 15 healthy participants in terms of electroencephalogram (EEG) responses and subjective experience. We found that vibrotactile stimulation from the glove could evoke 40 Hz EEG responses in the central, frontal and, to a lesser extent, occipital cortices. We also observed distinct patterns of functional connectivity between the two stimulation modalities. Participants preferred the vibrotactile stimulation over the visual and auditory stimulation. Our study supports future investigations on vibrotactile stimulation for the treatment of neurological conditions.

bioengineering↗

bioRxiv2023

Swimming with the current improves juvenile survival in southern elephant seals

Understanding juvenile survival is crucial for the population ecology of long-lived species, where parental guidance can significantly influence survival rates of completely naive juveniles. In southern elephant seals (Mirounga leonina), however, offspring receive no knowledge from their parents, only fat reserves. This research focuses on how dispersal direction on their maiden foraging trip and physical traits influence the survival of naive southern elephant seal pups at Macquarie Island. We tracked 44 pups with satellite tags during their post-weaning migration and compared their movements to the post-moult winter migrations of 58 adult females. We found that most pups (61.2%) travelled southeast, in line with the Antarctic Circumpolar Current. Pups travelling with the predominant east-southeast current had a 1.5 times higher survival rate for their first trip than those swimming westward against it. Those that swam with the current and were heavier were more likely to survive their first year. Adult females showed different dispersal patterns, where they travelled southwards towards Antarctic waters, implying that learning from experience influences their direction. Future investigations into the role of the primary eastward current in the sub-Antarctic on circumpolar movement patterns of top marine predators could expand our understanding of Southern Ocean ecology.

ecology↗