Repair Of Injury Research Articles

Non-Coding RNA in Schwann Cell and Peripheral Nerve Injury: A Review.

Peripheral nerve injury (PNI) can result in severe disabilities, profoundly impacting patients' quality of life and potentially endangering their lives. Therefore, understanding the potential molecular mechanisms that facilitate the regeneration of damaged nerves is crucial. Evidence indicates that Schwann cells (SCs) play a pivotal role in repairing peripheral nerve injuries. Previous studies have shown that RNA, particularly non-coding RNA (ncRNA), plays a crucial role in nerve regeneration, including the proliferation and dedifferentiation of SCs. In this review, the individual roles of ncRNA in SCs and PNI are analyzed. This review not only enhances the understanding of ncRNA's role in nerve injury repair but also provides a significant theoretical foundation and inspiration for the development of new therapeutic strategies.

Biomimetic multi-channel nerve conduits with micro/nanostructures for rapid nerve repair

Peripheral nervous system (PNS) injuries often lead to significant sensory and motor impairments. Traditional artificial nerve conduits, lacking anisotropic structures, have been associated with prolonged repair time and failures in nerve regeneration. This study aimed to address these challenges by developing a novel approach for rapid repair of peripheral nerve injuries (PNI). A 3D oriented fibers scaffold featuring distinct radial (RFs) and longitudinal (LFs) fibers orientations was engineered using coaxial electrospinning and gas directional foaming techniques. This scaffold was then integrated with a shape memory conduit to form a directional multi-channel nerve conduit with micro/nanostructures. The results revealed that the grooved surface of the fibers significantly improved cellular directional guidance, effectively facilitating the migration of SCs from the periphery towards the center and from the base to the apex of the scaffold. In a rat model with a 10 mm nerve defect, the ND-PLATMC/LF ND-PCL scaffold significantly enhanced nerve regeneration and motor function recovery within 4 weeks. These results suggest the potential of this innovative scaffold for efficient repair of the nerve injuries.

Failed primary repair of blunt duodenal injury managed by tube duodenostomy, gastrojejunostomy and a feeding jejunostomy: a case report

BackgroundThe worldwide increase in road traffic crashes and use of firearms has increased the incidence of duodenal injuries. Upper gastrointestinal radiological studies and computed tomography (CT) in resource settings may lead to the diagnosis of blunt duodenal injury. Exploratory laparotomy remains the ultimate diagnostic test if a high suspicion of duodenal injury continues in the face of absent or equivocal radiographic signs. Although the majority of duodenal injuries may be managed by simple repair, high-risk duodenal injuries are followed by a high incidence of suture line dehiscence and should be treated by duodenal diversion.Case presentationWe report a case of a failed primary repair of a blunt injury to the second part of the duodenum (D2) in a 24-year-old African man. This was successfully managed by a tube duodenostomy, a bypass gastrojejunostomy and a feeding jejunostomy in a low resource setting.ConclusionsDetailed knowledge of the available operative choices in duodenal injury and their correct application is important. When duodenal repair is needed, conservative repair techniques over complex reconstructions should be utilised. The technique of tube duodenostomy can be successfully applied to cases of large defects in the second part of the duodenum (D2), failed previous repair attempts and with defects caused by different aetiology. It may remain especially useful as a damage-control procedure in patients with multiple injuries, significant comorbidities and/or haemodynamic instability.

Trends in Duodenal Injury Severity, Repair, and Mortality Over Time

IntroductionOutcomes for patients with traumatic duodenal injury are determined by the location of the injury, injury severity, and associated injuries. We hypothesized that there is an association among the increased frequency of firearm injuries, the severity of duodenal injuries, trends in repair techniques, and mortality. MethodsDuodenal injuries managed at an adult level 1 hospital from 2000 to 2022 were identified. Demographics, injury type, the American Association for the Surgery of Trauma (AAST) grade, type of surgical repair, and mortality data were obtained and aggregated into two periods (2000 to June 2011 and July 2011 to 2022) to evaluate trends over time. P values < 0.05 were considered significant. ResultsOne hundred eighty eight cases were identified. Duodenal injuries due to firearms increased over time (30% versus 55%, P < 0.001). The distribution of AAST injury grade shifted over time with fewer grade 1 and more grade 2 to 4 injuries in the later period (P = 0.002). AAST grade 2 injuries or higher were more likely due to firearms (P < 0.001). Despite more high-grade injuries, there was no change in the use of primary repair with or without tube drainage (61% versus 70%, P = 0.35) and there was no change in mortality (15% versus 17%, P value 0.62) between the time periods. ConclusionsThere was a proportional increase in the number of duodenal injuries caused by firearms. Higher grade duodenal injuries were more common with firearm injuries and were predominately repaired with simple techniques with no increase in mortality.

The Exploratory Study of the PTEN-AKT/mTOR Signaling Pathway in the Corresponding Dorsal Root Ganglion during Compensatory Repair via Small Gap Amplification in Sciatic Nerve Injury.

Peripheral nerve injury is a challenging orthopedic issue in clinical management that often leads to limb dysfunction or even disability in severe cases. A thorough exploration of the repair process of peripheral nerve injury and the underlying mechanism contributes to formulate more effective therapeutic strategies. In the present study, we established a sciatic nerve transection injury model in Sprague-Dawley (SD) rats. A 12-week compensatory repair of sciatic nerve transection injury using a chitin cannula for small gap anastomosis was then performed via sleeve jointing the proximal common peroneal nerve to the distal tibial nerve and common peroneal nerve, with a 2 mm interval. Compensatory repair via small gap amplification was observed via gross observation of nerve specimen, osmic acid staining, and electrophysiological stimulation of sciatic nerve branches of the tibial and common peroneal nerve. Rat limbs were observed, and the functional recovery of effector muscles of the gastrocnemius and tibialis anterior muscles was assessed through weighing the muscle wet weight, Hematoxylin and Eosin (H&E) staining, and muscle strength detection. H&E staining, Masson staining, and toluidine blue staining were performed to observe the morphological changes of the dorsal root ganglion. Positive expressions of key proteins involved in the Phosphatase and tensin homologue deleted on chromosome ten (PTEN)-protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway, including PTEN, AKT, mTOR, Toll-like receptor 4 (TLR4), and Caspase9 in the dorsal root ganglion during compensatory repair of sciatic nerve after injury via small gap amplification, were detected by immunohistochemical staining. It is found that the compensatory repair of sciatic nerve transection injury using a chitin cannula for small gap anastomosis via sleeve jointing effectively restored the continuity, number of myelinated nerve fibers, and nerve conduction velocity. It promoted toe abduction recovery, improved muscle fiber morphology and increased the wet weight and muscle strength of the gastrocnemius muscle and tibialis anterior muscle. Moreover, it increased the number of neurons and nerve fibers, and improved their morphology. Downregulated PTEN, TLR4, and Caspase9 in the dorsal root ganglia and upregulated AKT and mTOR were observed after small gap amplification than those of the transection injury group, which were closer to those of the control group. Compensatory repair of sciatic nerve transection injury using a chitin cannula for small gap anastomosis via sleeve jointing can restore the morphology and function of the sciatic nerve, effector muscles, and corresponding dorsal root ganglia by activating the PTEN-AKT/mTOR signaling pathway in the dorsal root ganglia. Our findings provide novel therapeutic targets for peripheral nerve injuries.

Research Progress of Massage on Repair of Peripheral Nerve Injury based on ‘Macrophages’

Research Progress of Massage on Repair of Peripheral Nerve Injury based on ‘Macrophages’

Design and preparation of hydrogel microspheres for spinal cord injury repair.

A severe disorder known as spinal cord damage causes both motor and sensory impairment in the limbs, significantly reducing the patients' quality of life. After a spinal cord injury, functional recovery and therapy have emerged as critical concerns. Hydrogel microspheres have garnered a lot of interest lately because of their enormous promise in the field of spinal cord injury rehabilitation. The material classification of hydrogel microspheres (natural and synthetic macromolecule polymers) and their synthesis methods are examined in this work. This work also covers the introduction of several kinds of hydrogel microspheres and their use as carriers in the realm of treating spinal cord injuries. Lastly, the study reviews the future prospects for hydrogel microspheres and highlights their limitations and problems. This paper can offer feasible ideas for researchers to advance the application of hydrogel microspheres in the field of spinal cord injury.

C286, an orally available retinoic acid receptor β agonist drug, regulates multiple pathways to achieve spinal cord injury repair.

Retinoic acid receptor β2 (RARβ2) is an emerging therapeutic target for spinal cord injuries (SCIs) with a unique multimodal regenerative effect. We have developed a first-in-class RARβ agonist drug, C286, that modulates neuron-glial pathways to induce functional recovery in a rodent model of sensory root avulsion. Here, using genome-wide and pathway enrichment analysis of avulsed rats' spinal cords, we show that C286 also influences the extracellular milieu (ECM). Protein expression studies showed that C286 upregulates tenascin-C, integrin-α9, and osteopontin in the injured cord. Similarly, C286 remodulates these ECM molecules, hampers inflammation and prevents tissue loss in a rodent model of spinal cord contusion C286. We further demonstrate C286's efficacy in human iPSC-derived neurons, with treatment resulting in a significant increase in neurite outgrowth. Additionally, we identify a putative efficacy biomarker, S100B, which plasma levels correlated with axonal regeneration in nerve-injured rats. We also found that other clinically available retinoids, that are not RARβ specific agonists, did not lead to functional recovery in avulsed rats, demonstrating the requirement for RARβ specific pathways in regeneration. In a Phase 1 trial, the single ascending dose (SAD) cohorts showed increases in expression of RARβ2 in white blood cells correlative to increased doses and at the highest dose administered, the pharmacokinetics were similar to the rat proof of concept (POC) studies. Collectively, our data suggests that C286 signalling in neurite/axonal outgrowth is conserved between species and across nerve injuries. This warrants further clinical testing of C286 to ascertain POC in a broad spectrum of neurodegenerative conditions.

Preparation and properties of biomimetic bone repair hydrogel with sandwich structure.

One of the critical factors that determines the biological properties of scaffolds is their structure. Due to the mechanical and structural discrepancies between the target bone and implants, the poor internal architecture design and difficulty in degradation of conventional bone implants may cause several adverse outcomes. To date, many scaffolds, such as 3-D printed sandwich structures, have been successfully developed for the repair of bone defects; however, the steps of these methods are complex and costly. Hydrogels have emerged as a unique scaffold material for repairing bone defects because of their good biocompatibility and excellent physicochemical properties. However, studies exploring bioinspired hydrogel scaffolds with hierarchical structures are scarce. More efforts are needed to incorporate bioinspired structures into hydrogel scaffolds to achieve optimal osteogenic properties. In this study, we developed a low-cost and easily available hydrogel matrix that mimicked the natural structure of the bone's porous sandwich to promote new bone growth and tissue integration. A comprehensive evaluation was conducted on the microstructure, swelling rate, and mechanical properties of this hydrogel. Furthermore, a 3D finite element analysis was employed to model the structure-property relationship. The results indicate that the sandwich-structured hydrogel is a promising scaffold material for bone injury repair, exhibiting enhanced compressive stress, elastic modulus, energy storage modulus, and superior force transmission.

Impact of ligation versus repair of isolated popliteal vein injuries on Deep Vein Thrombosis and Pulmonary Embolism incidence in trauma patients: a meta-analysis.

Traumatic injuries affecting the veins in the lower extremities have been correlated with both mortality and severe complications. Venous injuries are recognized as a contributing factor to the development of venous thromboembolism, commonly treated through procedures involving either vein ligation or repair. Despite previous efforts, substantial uncertainty remains when it comes to choosing between the execution of ligation versus various reparative techniques. The aim of this study was to evaluate the short-term results of surgically treating traumatic venous injuries through repair compared to ligation, specifically examining the resulting impacts on trauma patients in relation to DVT and PE occurrences. A comprehensive search strategy was employed until August 10, 2023, to systematically explore Scopus and PubMed databases. Following the removal of duplicates, two researchers independently assessed the titles and abstracts of the identified studies. Only studies meeting the project's requirements and inclusion criteria, as evaluated through their full texts, were included in our investigation. Our study exclusively focused on original articles, specifically those involving human trauma patients with isolated popliteal vein injuries. Excluded from consideration were review articles, meta-analyses, cellular and molecular research, animal studies, case reports, case series, letters to the editor, posters, duplicates, and publications in languages other than English. The implementation of this systematic review and meta-analysis conformed to the standards delineated in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Conducting a thorough search, the inquiry identified 248 records. The assessment of titles and abstracts led to 51 studies that had the potential for eligibility. After reviewing the full texts of the chosen studies, 4 studies involving 1521 patients constituted the ultimate findings. We concluded that the ligation procedure had a higher incidence of pulmonary embolism compared to the repair of vein injuries, while the repair procedure had a higher incidence of deep vein thrombosis than ligation. Additional large-scale randomized controlled trials are still necessary to further support the findings of this meta-analysis.

To target cellular senescence in diabetic kidney disease: the known and the unknown.

Cellular senescence represents a condition of irreversible cell cycle arrest, characterized by heightened senescence-associated beta-galactosidase (SA-β-Gal) activity, senescence-associated secretory phenotype (SASP), and activation of the DNA damage response (DDR). Diabetic kidney disease (DKD) is a significant contributor to end-stage renal disease (ESRD) globally, with ongoing unmet needs in terms of current treatments. The role of senescence in the pathogenesis of DKD has attracted substantial attention with evidence of premature senescence in this condition. The process of cellular senescence in DKD appears to be associated with mitochondrial redox pathways, autophagy, and endoplasmic reticulum (ER) stress. Increasing accumulation of senescent cells in the diabetic kidney not only leads to an impaired capacity for repair of renal injury, but also the secretion of pro-inflammatory and profibrotic cytokines and growth factors causing inflammation and fibrosis. Current treatments for diabetes exhibit varying degrees of renoprotection, potentially via mitigation of senescence in the diabetic kidney. Targeting senescent cell clearance through pharmaceutical interventions could emerge as a promising strategy for preventing and treating DKD. In this paper, we review the current understanding of senescence in DKD and summarize the possible therapeutic interventions relevant to senescence in this field.

Midterm complications after primary obstetrical anal sphincter injury repair in France

BackgroundIncidence of complications following obstetrical anal sphincter injury (OASI) during vaginal delivery are poorly defined. They are only studied in high level maternities, small cohorts, all stages of perineal tear or in low-income countries. The aim of our study was to describe complications after primary OASI repair following a vaginal delivery in all French maternity wards at short and midterm and to assess factors associated with complication occurrence.MethodsWe conducted a historical cohort study using the French nationwide claim database (PMSI) from January 2013 to December 2021. All women who sustained an OASI repair following a vaginal delivery were included and virtually followed-up for 2 years. Then, we searched for OASIS complications. Finally, we evaluated factors associated with OASIS complication repaired or not and OASIS complication repairs.ResultsAmong the 61,833 included women, 2015 (2.8%) had an OASI complication and 842 (1.16%) underwent an OASI complication repair. Women were mainly primiparous (71.6%) and 44.3% underwent an instrumental delivery. During a follow-up of 2 years, 0.6% (n = 463), 0.3% (n = 240), 0.2% (n = 176), 0.1% (n = 84), 0.06% (n = 43) and 0.01% (n = 5) of patients underwent second surgery for a perineal repair, a fistula repair, a sphincteroplasty, a perineal infection, a colostomy and a sacral nervous anal stimulation, respectively. Only one case of artificial anal sphincter was noticed. Instrumental deliveries (OR = 1.56 CI95%[1.29;1.9]), private for-profit hospitals (OR = 1.42 [1.11;1.82], reference group “public hospital”), obesity (OR = 1.36 [1;1.84]), stage IV OASIS (OR = 2.98 [2.4;3.72]), perineal wound breakdown (OR = 2.8 [1.4;5.48]), ages between 25 and 29 years old (OR = 1.59 [1.17;2.18], refence group “age between 13 and 24 years old”) and 30 and 34 years old (OR = 1.57 [1.14; 2.16], refence group “age between 13 and 24 years old”) were factors associated with OASIS complication repairs.ConclusionsMaternal age, stage IV OASIS, obesity, instrumental deliveries and private for-profit hospitals seemed to predict OASIS complications. Understanding factors associated with OASIS complications could be beneficial for the patient to inform them and to influence the patient’s follow-up in order to prevent complications, repairs and maternal distress.

Biodegradable conductive hydrogels generating magnetic-field-driven wireless electrical stimulation enhance the spinal cord injury repair

Despite the promising application of electrical stimulation (ES) in promoting tissue repair within regenerative medicine, current ES technologies are constrained in commonly requiring a tissue-traversing wiring and external power source. To explore a wireless ES technology for translational medicine, we developed an injectable, biodegradable, conductive hydrogel scaffold, which can offer facile in situ ES via electromagnetic induction effect, and demonstrated its successful application in spinal cord injury (SCI) repair. The conductive hydrogel was constructed with hyaluronic acid (HA) and germanium phosphorus (GeP3) nanosheets, where the GeP3 nanosheets not only work as biodegradable conductive fillers in injectable HA hydrogel, but also show excellent biocompatibility and antioxidant properties. In a complete transection model of SCI rats, when an alternating magnetic field (MF) was applied to the implanted HA/GeP3 hydrogel scaffold, the significant recovery of motor function can be observed. The immunohistochemical and molecular mechanism investigation suggests that the HA/GeP3 hydrogel with MF-driven ES capability can effectively promote angiogenesis, remyelination, axonal regeneration through activating calcium channels and downstream PI3K/AKT signaling pathway. The proposed phosphorus-based conductive hydrogel as a wireless in vivo ES platform would offer great potential for tissue engineering applications to enhance the repairing of various electro-active tissues, including nerves, heart, and skeletal muscles.

Biomineralized MnO2 Nanoparticle-Constituted Hydrogels Promote Spinal Cord Injury Repair by Modulating Redox Microenvironment and Inhibiting Ferroptosis.

Spinal cord injury (SCI) is one of the most severe injuries, characterized by multiple positive feedback regulatory signaling networks formed by oxidative stress and inflammation in the injury microenvironment, leading to neuronal cell damage and even death. Here, astragaloside IV (AS), known for its regulatory role in ferroptosis, was encapsulated in the cavity of apoferritin (HFn) after an in situ biomineralization process involving MnO2, resulting in the synthesis of HFn@MnO2/AS nanoparticles. These nanoparticles were then dispersed in chitosan/polyvinyl alcohol/glutaraldehyde/sodium β-glycerophosphate (CGPG) hydrogels to form CGPG-HFn@MnO2/AS injectable thermosensitive hydrogels that can scavenge reactive oxygen species (ROS) in the microenvironment. Our findings indicated that the prepared CGPG-HFn@MnO2/AS hydrogel exhibited remarkable efficacy in scavenging ROS in vitro, effectively ameliorating the oxidative stress microenvironment post-SCI. Furthermore, it inhibited oxidative stress-induced ferroptosis in vitro and in vivo by regulating SIRT1 signaling, thereby promoting neuronal cell migration and repair. Hence, the developed hydrogel combining MnO2 and AS exhibited multifaceted abilities to modulate the pathological microenvironment, providing a promising therapeutic strategy for central nervous system (CNS) diseases.

Nanorepair medicine for treatment of organ injury.

Organ injuries, such as acute kidney injury, ischemic stroke, and spinal cord injury, often result in complications that can be life-threatening or even fatal. Recently, many nanomaterials have emerged as promising agents for repairing various organ injuries. In this review, we present the important developments in the field of nanomaterial-based repair medicine, herein referred to as 'nanorepair medicine'. We first introduce the disease characteristics associated with different types of organ injuries and highlight key examples of relevant nanorepair medicine. We then provide a summary of existing strategies in nanorepair medicine, including organ-targeting methodologies and potential countermeasures against exogenous and endogenous pathologic risk factors. Finally, we offer our perspectives on current challenges and future expectations for the advancement of nanomedicine designed for organ injury repair.

Epigenetic reprogramming driving successful and failed repair in acute kidney injury.

Acute kidney injury (AKI) causes epithelial damage followed by subsequent repair. While successful repair restores kidney function, this process is often incomplete and can lead to chronic kidney disease (CKD) in a process called failed repair. To better understand the epigenetic reprogramming driving this AKI-to-CKD transition, we generated a single-nucleus multiomic atlas for the full mouse AKI time course, consisting of ~280,000 single-nucleus transcriptomes and epigenomes. We reveal cell-specific dynamic alterations in gene regulatory landscapes reflecting, especially, activation of proinflammatory pathways. We further generated single-nucleus multiomic data from four human AKI samples including validation by genome-wide identification of nuclear factor κB binding sites. A regularized regression analysis identifies key regulators involved in both successful and failed repair cell fate, identifying the transcription factor CREB5 as a regulator of both successful and failed tubular repair that also drives proximal tubular cell proliferation after injury. Our interspecies multiomic approach provides a foundation to comprehensively understand cell states in AKI.

Regenerative Role of Lrig1+ Cells in Kidney Repair.

In response to severe kidney injury, the kidney epithelium displays remarkable regenerative capabilities driven by adaptable resident epithelial cells. To date, it has been widely considered that the adult kidney lacks multipotent stem cells; thus, the cellular lineages responsible for repairing proximal tubule damage are incompletely understood. Leucine-rich repeats and immunoglobulin-like domains protein 1-expressing cells (Lrig1+ cells) have been identified as a long-lived cell in various tissues that can induce epithelial tissue repair. Therefore, we hypothesized that Lrig1+ cells participate in kidney development and tissue regeneration. We investigated the role of Lrig1+ cells in kidney injury using mouse models. The localization of Lrig1+ cells in the kidney was examined throughout mouse development. The function of Lrig1+ progeny cells in acute kidney injury repair was examined in vivo using a tamoxifen-inducible Lrig1-specific Cre recombinase-based lineage tracing in three different kidney injury mouse models. Additionally, we conducted single-cell RNA-sequencing to characterize the transcriptional signature of Lrig1+ cells and to trace their progeny. Lrig1+ cells were present during kidney development and contributed to formation of the proximal tubule and collecting duct structures in mature mouse kidneys. In three-dimensional culture, single Lrig1+ cells demonstrated long-lasting propagation and differentiated into the proximal tubule and collecting duct lineages. These Lrig1+ proximal tubule cells highly expressed progenitor-like and quiescence-related genes, giving rise to a novel cluster of cells with regenerative potential in adult kidneys. Moreover, these long-lived Lrig1+ cells expanded and repaired damaged proximal tubules in response to three types of acute kidney injury in mice. These findings highlight the critical role of Lrig1+ cells in kidney regeneration.

Repair of spinal cord injury by bone marrow mesenchymal stem cell-derived exosomes: a systematic review and meta-analysis based on rat models.

This study aims to systematically evaluate the efficacy of bone marrow mesenchymal stem cell-derived exosomes (BMSCs-Exo) in improving spinal cord injury (SCI) to mitigate the risk of translational discrepancies from animal experiments to clinical applications. We conducted a comprehensive literature search up to March 2024 using PubMed, Embase, Web of Science, and Scopus databases. Two researchers independently screened the literature, extracted data, and assessed the quality of the studies. Data analysis was performed using STATA16 software. A total of 30 studies were included. The results indicated that BMSCs-Exo significantly improved the BBB score in SCI rats (WMD = 3.47, 95% CI [3.31, 3.63]), inhibited the expression of the pro-inflammatory cytokine TNF-α (SMD = -3.12, 95% CI [-3.57, -2.67]), and promoted the expression of anti-inflammatory cytokines IL-10 (SMD = 2.76, 95% CI [1.88, 3.63]) and TGF-β (SMD = 3.89, 95% CI [3.02, 4.76]). Additionally, BMSCs-Exo significantly reduced apoptosis levels (SMD = -4.52, 95% CI [-5.14, -3.89]), promoted the expression of axonal regeneration markers NeuN cells/field (SMD = 3.54, 95% CI [2.65, 4.42]), NF200 (SMD = 4.88, 95% CI [3.70, 6.05]), and the number of Nissl bodies (SMD = 1.89, 95% CI [1.13, 2.65]), and decreased the expression of astrogliosis marker GFAP (SMD = -5.15, 95% CI [-6.47, -3.82]). The heterogeneity among studies was primarily due to variations in BMSCs-Exo transplantation doses, with efficacy increasing with higher doses. BMSCs-Exo significantly improved motor function in SCI rats by modulating inflammatory responses, reducing apoptosis, inhibiting astrogliosis, and promoting axonal regeneration. However, the presence of selection, performance, and detection biases in current animal experiments may undermine the quality of evidence in this study.

PTEN in kidney diseases: a potential therapeutic target in preventing AKI-to-CKD transition.

Renal fibrosis, a critical factor in the development of chronic kidney disease (CKD), is predominantly initiated by acute kidney injury (AKI) and subsequent maladaptive repair resulting from pharmacological or pathological stimuli. Phosphatase and tensin homolog (PTEN), also known as phosphatase and tensin-associated phosphatase, plays a pivotal role in regulating the physiological behavior of renal tubular epithelial cells, glomeruli, and renal interstitial cells, thereby preserving the homeostasis of renal structure and function. It significantly impacts cell proliferation, apoptosis, fibrosis, and mitochondrial energy metabolism during AKI-to-CKD transition. Despite gradual elucidation of PTEN's involvement in various kidney injuries, its specific role in AKI and maladaptive repair after injury remains unclear. This review endeavors to delineate the multifaceted role of PTEN in renal pathology during AKI and CKD progression along with its underlying mechanisms, emphasizing its influence on oxidative stress, autophagy, non-coding RNA-mediated recruitment and activation of immune cells as well as renal fibrosis. Furthermore, we summarize prospective therapeutic targeting strategies for AKI and CKD-treatment related diseases through modulation of PTEN.

Transplantation of miR-145a-5p modified M2 type microglia promotes the tissue repair of spinal cord injury in mice

BackgroundThe traumatic spinal cord injury (SCI) can cause immediate multi-faceted function loss or paralysis. Microglia, as one of tissue resident macrophages, has been reported to play a critical role in regulating inflammation response during SCI processes. And transplantation with M2 microglia into SCI mice promotes recovery of motor function. However, the M2 microglia can be easily re-educated and changed their phenotype due to the stimuli of tissue microenvironment. This study aimed to find a way to maintain the function of M2 microglia, which could exert an anti-inflammatory and pro-repair role, and further promote the repair of spinal cord injury.MethodsTo establish a standard murine spinal cord clip compression model using Dumont tying forceps. Using FACS, to sort microglia from C57BL/6 mice or CX3CR1GFP mice, and further culture them in vitro with different macrophage polarized medium. Also, to isolate primary microglia using density gradient centrifugation with the neonatal mice. To transfect miR-145a-5p into M2 microglia by Lipofectamine2000, and inject miR-145a-5p modified M2 microglia into the lesion sites of spinal cord for cell transplanted therapy. To evaluate the recovery of motor function in SCI mice through behavior analysis, immunofluorescence or histochemistry staining, Western blot and qRT-PCR detection. Application of reporter assay and molecular biology experiments to reveal the mechanism of miR-145a-5p modified M2 microglia therapy on SCI mice.ResultsWith in vitro experiments, we found that miR-145a-5p was highly expressed in M2 microglia, and miR-145a-5p overexpression could suppress M1 while promote M2 microglia polarization. And then delivery of miR-145a-5p overexpressed M2 microglia into the injured spinal cord area significantly accelerated locomotive recovery as well as prevented glia scar formation and neuron damage in mice, which was even better than M2 microglia transplantation. Further mechanisms showed that overexpressed miR-145a-5p in microglia inhibited the inflammatory response and maintained M2 macrophage phenotype by targeting TLR4/NF-κB signaling.ConclusionsThese findings indicate that transplantation of miR-145a-5p modified M2 microglia has more therapeutic potential for SCI than M2 microglia transplantation from epigenetic perspective.Graphical