Biology subjects

Terashima, C.

Publications and source records attributed to Terashima, C..

3 recordsLinked to original sources

bioRxiv2024

Muscle-derived miR-200a-3p through light-intensity exercise may contribute to improve memory dysfunction in type 2 diabetic mice

BackgroundMemory dysfunction associated with type 2 diabetes mellitus (T2DM) poses a considerable threat to overall well-being. Engaging in light-intensity exercise has been shown to exert favorable effects on hippocampal function and molecular profiles, including Mct2 mRNA and miR-200a-3p. Nonetheless, a comprehensive understanding of the mechanisms underlying the positive impact of light-intensity exercise remains elusive. Here, we assessed the influence of exosomal miR-200a-3p secretion from gastrocnemius muscles in T2DM mice undergoing light-intensity exercise intervention, focusing on its potential to ameliorate memory dysfunction. Basic proceduresWe initially assessed the effects of light-intensity exercise (7.0 m/min for healthy mice, 5.0 m/min for ob/ob mice, 30 min/day, five days/week, over a four-week period) on memory function, hippocampal mRNA associated with memory function, and the secretion of exosomal miR-200a-3p from their gastrocnemius muscle. Subsequently, the impact of a daily intraperitoneal injection of the miR-200a-3p mimic over a four-week duration was investigated, focusing on its influence on hippocampal dysregulation in ob/ob mice. Main findingsThe light-intensity exercise intervention increased gastrocnemius muscle-derived and plasma exosomal miR-200a-3p levels in ob/ob mice, concomitant with improved memory dysfunction. Intriguingly, the daily intraperitoneal injection of mmu-miR-200a-3p mimic also demonstrated an ameliorative effect on memory function in ob/ob mice. Notably, both the exercise intervention and miR-200a-3p mimic treatment induced downregulation in hippocampal Keap1 mRNA and upregulation in mRNA of Hsp90aa1 and Mct2 in ob/ob mice. Principal conclusionsThe current results imply that the augmentation of exosomal miR-200a-3p derived from the gastrocnemius muscle contributes to the amelioration of memory dysfunction in T2DM undergoing light-intensity exercise. Additionally, it is proposed that miR-200a-3p emulates the effects of light-intensity exercise, suggesting a potential therapeutic pathway for addressing hippocampal complications in the context of T2DM.

neuroscience↗

bioRxiv2024

Feeding a low-carbohydrate and high-protein diet diminishes working memory in healthy mice: possible involvement of miR-539-3p/Lrp6/Igf1r axis in the hippocampus

A low-carbohydrate and high-protein (LC-HP) diet demonstrates favorable impacts on metabolic parameters, albeit it leads to a decline in hippocampal function among healthy mice. The reduction in working memory induced by LC-HP diets is attributed to the decreased expression of hippocampal IGF-1 receptor (IGF-1R). However, the precise mechanisms underlying this phenomenon remain unexplored. Here, we investigated that by analyzing alterations in hippocampal miRNA profiles. C57BL/6 mice were divided into the LC-HP diet-fed group (25.1% carbohydrate, 57.2% protein, and 17.7% fat as percentages of calories) and the control diet-fed group (58.9% carbohydrate, 24.0% protein, and 17.1% fat as percentages of calories). After four weeks, all mice underwent the Y-maze test, followed by analyses of mRNA and miRNA expressions in the hippocampus. Our investigation revealed that feeding the LC-HP diet suppressed working memory function and hippocampal Igf1r mRNA levels in mice. Sequencing of miRNA demonstrated 17 upregulated and 27 downregulated miRNAs in the hippocampus of LC-HP diet-fed mice. Notably, upregulation of miR-539-3p, predicted to modulate Igf1r gene expression, was observed. Consequently, we found decreased hippocampal mRNA levels of low-density lipoprotein receptor-related protein 6 (Lrp6), a gene modulated by miR-539-3p, in mice fed the LC-HP diet. Furthermore, a significant positive correlation was observed between Lrp6 and Igf1r mRNA levels in the hippocampus. These findings suggest that LC-HP diets may suppress hippocampal function via the miR-539-3p/Lrp6/Igf1r axis, offering a potential target for nutritional strategies to preserve hippocampal health.

neuroscience↗

bioRxiv2024

Augmented-reality-based exercise increases salivary oxytocin

Exercise is known to have positive effects on psychological well-being, with team sports often associated with superior mental health compared to individual sports. Augmented reality (AR) technology has the potential to convert solitary exercise into multi-person exercise. Given the role of oxytocin in mediating the psychological benefits of exercise and sports, this study aimed to investigate the impact of AR-based multi-person exercise on mood and salivary oxytocin levels. Fourteen participants underwent three distinct regimens: non-exercise (Rest), standard solitary cycling exercise (Ex), and AR-based multi-person cycling exercise (Ex+AR). In both exercise conditions (Ex and Ex+AR), participants engaged in cycling at a self-regulated pace to maintain a Rating of Perceived Exertion of 10. In the Ex+AR condition, participants avatars were projected onto a tablet screen, allowing them to cycle alongside ten other virtual avatars in an AR environment. Mood states (assessed using POMS2) and saliva samples were collected before and immediately after each 10-minute regimen. Subsequently, the levels of salivary oxytocin were measured. Participants exhibited higher cycling speeds during Ex+AR compared to Ex, despite comparable levels of self-reported fatigue between the two groups. Notably, only the Ex+AR condition significantly improved mood states associated with depression-dejection and exhibited a trend toward suppressing anger-hostility in participants. Moreover, the Ex+AR condition led to a significant elevation in salivary oxytocin levels, while the Ex condition showed a trend toward an increase. However, changes in salivary oxytocin did not show a significant correlation with changes in mood states. These findings suggest that Ex+AR enhances mood states and promotes oxytocin release. AR-based multi-person exercise may offer greater psychological benefits compared to standard solitary exercise, although the relationship between oxytocin and mood changes remains inconclusive. HighlightsO_LIExercise, especially team sports, has positive effects on mood state, and oxytocin partially supports these effects. C_LIO_LIAugmented reality (AR) technology can potentially convert standard solitary exercise into multi-person exercise. C_LIO_LIAR-based multi-person exercise (Ex+AR) significantly ameliorated depression-dejection and increased salivary oxytocin levels, but standard solitary exercise did not. C_LIO_LIEx+AR may provide more significant psychological benefits than standard solitary exercise. C_LI

physiology↗