RNF14 is a regulator of mitochondrial and immune function in muscle. Ingham Aaron B,Osborne Simone A,Menzies Moira,Briscoe Suzie,Chen Wei,Kongsuwan Kritaya,Reverter Antonio,Jeanes Angela,Dalrymple Brian P,Wijffels Gene,Seymour Robert,Hudson Nicholas J BMC systems biology BACKGROUND:Muscle development and remodelling, mitochondrial physiology and inflammation are thought to be inter-related and to have implications for metabolism in both health and disease. However, our understanding of their molecular control is incomplete. RESULTS:In this study we have confirmed that the ring finger 14 protein (RNF14), a poorly understood transcriptional regulator, influences the expression of both mitochondrial and immune-related genes. The prediction was based on a combination of network connectivity and differential connectivity in cattle (a non-model organism) and mice data sets, with a focus on skeletal muscle. They assigned similar probability to mammalian RNF14 playing a regulatory role in mitochondrial and immune gene expression. To try and resolve this apparent ambiguity we performed a genome-wide microarray expression analysis on mouse C2C12 myoblasts transiently transfected with two Rnf14 transcript variants that encode 2 naturally occurring but different RNF14 protein isoforms. The effect of both constructs was significantly different to the control samples (untransfected cells and cells transfected with an empty vector). Cluster analyses revealed that transfection with the two Rnf14 constructs yielded discrete expression signatures from each other, but in both cases a substantial set of genes annotated as encoding proteins related to immune function were perturbed. These included cytokines and interferon regulatory factors. Additionally, transfection of the longer transcript variant 1 coordinately increased the expression of 12 (of the total 13) mitochondrial proteins encoded by the mitochondrial genome, 3 of which were significant in isolated pair-wise comparisons (Mt-coxII, Mt-nd2 and mt-nd4l). This apparent additional mitochondrial function may be attributable to the RWD protein domain that is present only in the longer RNF14 isoform. CONCLUSIONS:RNF14 influences the expression of both mitochondrial and immune related genes in a skeletal muscle context, and has likely implications for the inter-relationship between bioenergetic status and inflammation. 10.1186/1752-0509-8-10

Hydrogen sulfide-modified extracellular vesicles from mesenchymal stem cells for treatment of hypoxic-ischemic brain injury. Chu Xili,Liu Dexiang,Li Tingting,Ke HongFei,Xin Danqing,Wang Shuhan,Cao Ying,Xue Hao,Wang Zhen Journal of controlled release : official journal of the Controlled Release Society We previously reported that preconditioning of mesenchymal stem cells (MSCs) with hydrogen sulfide (HS) improved their therapeutic potential in cerebral ischemia. However, the mechanisms involved with this effect have not been determined. As one approach to address this issue, we focused on a neuroprotective role of modification of MSCs-derived extracellular vesicles (EVs) with HS treatment, and further examined the underlying mechanisms during hypoxia-ischemia (HI) injury in neonatal mice. At 24 h following HI insult, neonatal mice received either systemically administered EVs (derived from MSCs) or HS-EVs (derived from NaHS-preconditioned MSCs). Both treatments reached the injured region of the ipsilateral hemisphere within 2 h after administration and were incorporated into microglia and neurons. Mice receiving HS-EVs exhibited substantially lower amounts of brain tissue loss, decreased levels of pro-inflammatory mediators, and a skewed distribution of CD45 microglia and CD45 brain mononuclear phagocytes toward a more anti-inflammatory condition as compared with that in mice receiving only EVs. Moreover, these neuroprotective and anti-inflammatory effects of HS-EVs were accompanied with long-term preservation of cognitive and memory functions, in contrast to the functional deficits observed in mice receiving only EVs. This HS preconditioning upregulated miR-7b-5p levels in EVs as determined with next-generation sequencing, while knockdown analyses revealed that inducing miR-7b-5p expression and targeting FOS in the ipsilateral cortex were essential for the neuroprotective and anti-inflammatory effects of HS-EVs following HI exposure. Taken together, these results demonstrate that miR-7b-5p transferred by HS-EVs into the ipsilateral hemisphere further induced miR-7b-5p expression, which promoted CD45 microglia and CD45 brain mononuclear phagocytes toward a beneficial phenotype and improved HI-induced cognitive impairments in neonatal mice. 10.1016/j.jconrel.2020.08.037

Mesenchymal stromal cell-derived extracellular vesicles modulate microglia/macrophage polarization and protect the brain against hypoxia-ischemic injury in neonatal mice by targeting delivery of miR-21a-5p. Acta biomaterialia Mesenchymal stromal cell (MSC)-derived extracellular vesicles (EVs) (MSC-EVs) exhibit protective effects in damaged or diseased tissues. However, the role of EVs secreted by MSC in hypoxia-ischemic (HI) injury in neonatal mice remains unknown. Systemic administration of MSC-EVs attenuated acute brain damage and neuroinflammation, and skewed CD11b/CD45 microglia and CD11b/CD45 brain monocyte/macrophage towards a more anti-inflammatory property as determined at 72 h post-HI. In addition, MSC-EVs remarkably improve the injury outcomes pups prior to weaning (P21), while no effect on long-term memory impairment (P42). Importantly, these effects were preceded by incorporation of MSC-EVs into a large number of neurons and microglia within HI group. Abundant levels of miR-21a-5p were present in EVs as determined with next-generation sequencing. Notably, MSC-EVs treatment further increased miR-21a-5p levels at 72 h post HI. Knockdown analyses revealed that miR-21a-5p, and its target-Timp3, were essential for this neuroprotective property of MSC-EVs following HI exposure as demonstrated in both in vitro and in vivo models. These findings suggest that a systemic administration of EVs derived from MSC, have the capacity to incorporated into neurons and microglia where they can then exert neuroprotection against HI-induced injury in neonates through the delivery of miR-21a-5p. 10.1016/j.actbio.2020.06.037