Mitochondrial dysfunction has been implicated in the pathogenesis of insulin resistance, the hallmark of type 2 diabetes mellitus (T2DM). However, the cause-effect relationship remains to be fully elucidated. Compelling evidence suggests that boosting mitochondrial function may represent a valuable therapeutic tool to improve insulin sensitivity. Mitochondria are highly dynamic organelles, which adapt to short- and long-term metabolic perturbations by undergoing fusion and fission cycles, spatial rearrangement of the electron transport chain complexes into supercomplexes and biogenesis governed by peroxisome proliferator-activated receptor γ co-activator 1α (PGC 1α). However, these processes appear to be dysregulated in type 2 diabetic individuals. Herein, we describe the mechanistic link between mitochondrial dysfunction and insulin resistance in skeletal muscle alongside the intracellular pathways orchestrating mitochondrial bioenergetics. We then review current evidence on nutritional tools, including fatty acids, amino acids, caloric restriction and food bioactive derivatives, which may enhance insulin sensitivity by therapeutically targeting mitochondrial function and biogenesis.

Assistive technology including virtual reality and augmented reality has gained interest as a novel intervention in a range of clinical settings. This technology has the potential to provide mental stimulation, a connection to autobiographical memory through reminiscence, and enhanced quality of life (QoL) to people living with dementia (PLWD) and mild cognitive impairment (MCI). In this mini-review, we examine the available evidence from studies reporting on the potential benefits of virtual and augmented reality to provide enjoyable, leisurely activities that may promote QoL and psychological well-being and facilitate social interaction. In total, 10 studies of varying study designs and durations (5 min to 6 months) using virtual (n = 9) and augmented reality (n = 1) were examined in PLWD (n = 6) and MCI (n= 3), in addition to 1 study that included participants with both conditions. Overall, the virtual experiences were enjoyed by the participants, improved their mood and apathy, and were preferred when compared with nonvirtual experiences. However, small sample sizes and variations in study design limit the generalizability of the results. Nevertheless, the use of virtual and augmented reality technology for PLWD and MCI is a novel and emerging method which may provide cognitive stimulation and improve well-being. Future research should explore the potential application of this technology to promote social interaction in both the community and aged care settings. We suggest future studies in PLWD and MCI assess the effects of more sustained use of virtual and augmented reality technology on psychological outcomes including QoL, apathy, and depressive symptoms, with the incorporation of physiological biomarker outcomes.

Social isolation and sedentary behaviour are common in residential aged care facilities (also known as nursing homes or long-term care). Use of new technologies such as virtual and augmented reality are currently under investigation for their potential to provide exciting and engaging activities for older people in residential aged care facilities. However, there is limited evidence on whether these technologies can promote physical activity in a small group setting for people with cognitive impairment. Using mixed methods, we examined the use of a virtual cycling experience in a sample of 10 participants with cognitive impairment living in residential aged care facilities. In a randomised crossover design, participants engaged in a 25-minute, self-paced, facilitated seated virtual cycling experience and a time-matched seated physical activity session in groups of five. All participants completed a brief pre- and post-intervention mood questionnaire. Video analysis was used for both conditions to compare levels of environmental stimulation, apathy and engagement using both the Person–Environment Apathy Rating Scale and the Engagement of a Person with Dementia Scale. A thematic analysis of semi-structured interviews following the virtual cycling experience was also performed. No differences were observed between conditions for all outcomes except for environmental stimulation, where there was a lower response in the intervention than the control condition ( p = 0.032). This was primarily driven by lower scores for the virtual cycling experience than control in physical accessibility ( p = 0.012). Participants reported the virtual cycling experience to be immersive and challenging and reminisced about cycling earlier in life. The activity manager observed that the virtual cycling experience was an overall positive experience and emphasised benefits of safety screening and preparation prior to the activities. The findings of this study support the use of the virtual cycling experience as an immersive and engaging alternative to usual activities, which might encourage higher levels of physical activity in residential aged care facilities.

Subcellular proteomics not only deepens our knowledge of what proteins are present within cells, but also opens our understanding as to where those proteins reside. Given the highly differentiated, cross-linked state of spermatozoa, such studies have proven difficult to perform. In this study we have fractionated spermatozoa into two components, consisting of either the head or flagellar region. Following SDS-PAGE, 1 mm slices were digested and used for LC-MS/MS analysis. In total, 1429 proteins were identified with 721 proteins being exclusively found in the tail and 521 exclusively in the head. Not only is this the largest reported proteomic analysis of human spermatozoa, but also it has provided novel insights into the compartmentalization of proteins, particularly receptors, never previously reported to be present in this cell type.

Rheumatoid arthritis is a progressive autoimmune disease characterised by severely swollen and painful joints. To compliment pharmacotherapy, people living with rheumatoid arthritis often turn to dietary interventions such as the Mediterranean diet. The aim of the present systematic review is to discuss the effects of the Mediterranean diet on the management and prevention of rheumatoid arthritis in human prospective studies. Four studies met the inclusion criteria, including two intervention studies reporting improvement in the pain visual analogue scale (p < 0.05) and a decrease in the health assessment questionnaire for rheumatoid arthritis score (p < 0.05) in the Mediterranean diet groups. Only one study reported a reduction in the 28 joint count disease activity score for rheumatoid arthritis for the Mediterranean diet group (p < 0.05). This review has identified beneficial effects of the Mediterranean diet in reducing pain and increasing physical function in people living with rheumatoid arthritis. However, there is currently insufficient evidence to support widespread recommendation of the Mediterranean diet for prevention of rheumatoid arthritis.

SummaryOxidative stress is known to have a major impact on human sperm function and, as a result, there is a need to develop sensitive methods for measuring reactive oxygen species (ROS) generation by these cells. A variety of techniques have been developed for this purpose including chemiluminescence (luminol and lucigenin), flow cytometry (MitoSOX Red, dihydroethidium, 4,5‐diaminofluorescein diacetate and 2′,7′‐dichlorodihydrofluorescein diacetate) and spectrophotometry (nitroblue tetrazolium). The relative sensitivity of these assays and their comparative ability to detect ROS generated in different subcellular compartments of human spermatozoa, have not previously been investigated. To address this issue, we have compared the performance of these assays when ROS generation was triggered with a variety of reagents including 2‐hydroxyestradiol, menadione, 4‐hydroxynonenal and arachidonic acid. The results revealed that menadione predominantly induced release of ROS into the extracellular space where these metabolites could be readily detected by luminol‐peroxidase and, to a lesser extent, 2′,7′‐dichlorodihydrofluorescein. However, such sensitivity to extracellular ROS meant that these assays were particularly vulnerable to interference by leucocytes. The remaining reagents predominantly elicited ROS generation by the sperm mitochondria and could be optimally detected by MitoSOX Red and DHE. Examination of spontaneous ROS generation by defective human spermatozoa revealed that MitoSOX Red was the most effective indicator of oxidative stress, thereby emphasizing the general importance of mitochondrial dysregulation in the aetiology of defective sperm function.

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