Tregs dysfunction aggravates postoperative cognitive impairment in aged mice

Metformin activates the PI3K/AKT/BDNF axis to attenuate postoperative cognitive dysfunction

Postoperative cognitive dysfunction (POCD) is a prevalent neurocognitive complication of anesthesia and surgery. Metformin, a widely used antidiabetic drug, has neuroprotective properties and improves cognitive impairment and memory deficits. However, the mechanisms underlying its action in improving cognitive dysfunction after anesthesia and surgery remain unclear. This study aimed to explore the effects of metformin on POCD and the underlying mechanisms at play. We established an in vivo POCD model using isoflurane inhalation anesthesia with exploratory laparotomy. We found that pretreatment with metformin significantly improved cognitive function and anxiety-like behaviors in mice. Additionally, metformin attenuated the impairment of synaptic plasticity induced by POCD and restored levels of synaptic proteins and dendritic density in the hippocampus. Furthermore, metformin attenuated neuroinflammation by downregulating the expression of interleukin (IL)-6, IL-1β, and tumor necrosis factor-α, and reducing neuronal apoptosis. It also activates the PI3K/AKT signaling pathway, resulting in increased expression of brain-derived neurotrophic factor (BDNF). Finally, the PI3K inhibitor, LY294002, reversed the effects of metformin on the levels of PI3K, AKT phosphorylation, and BDNF in vitro cultured HT-22 cells. Additionally, in an in vivo model of POCD, it was observed that cognitive function in mice was significantly suppressed by treatment with the PI3K inhibitor LY294002. These results reveal that metformin may alleviate POCD by modulating the PI3K/AKT/BDNF axis. Our study may provide a novel strategy for preventing and treating POCD with this medication.

Electroacupuncture improves postoperative cognitive dysfunction by inhibiting ferroptosis via the TFR1-DMT1-FPN pathway

OBJECTIVE

The aim of this study was to investigate the role of ferroptosis in the occurrence of postoperative cognitive dysfunction (POCD) using a mouse model and to elucidate whether electroacupuncture (EA) can improve POCD by suppressing ferroptosis via the transferrin receptor 1 (TFR1)-divalent metal transporter 1 (DMT1)-ferroportin (FPN) pathway.

METHODS

The experiment involved three groups: the control group, the POCD group and the POCD + EA group. The POCD animal model was established using sevoflurane anesthesia and tibial fracture. Cognitive and behavioral changes in mice were assessed using the novel object recognition test (NORT) and the Morris water maze (MWM) test, 1 and 3 days after surgery. Transmission electron microscopy was performed to observe changes in the mitochondrial structure of hippocampal tissue. Enzyme-linked immunosorbent assay was conducted to determine the levels of glutathione (GSH) and iron ion (Fe) concentrations. Western blot analysis was used to measure the expression of TFR1, DMT1 and iron pump protein. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was employed to detect the mRNA levels of DMT1 and FPN.

RESULTS

Based on the experimental results of the MWM test and the NORT, we found that EA can improve POCD in mice. Observation by projection electron microscopy showed that EA improved the mitochondrial structure in the hippocampus. The enzyme-linked immunosorbent assay (ELISA) results showed that EA suppressed ferroptosis in the hippocampal area. The qRT-PCR and Western blot results suggested that EA suppresses ferroptosis by regulating the TFR1-DMT1-FPN pathway.

CONCLUSION

This study reveals that sevoflurane and tibial fractures cause cognitive damage through the mechanism of ferroptosis, while EA may inhibit ferroptosis through the TFR1-DMT1-FPN pathway and improve POCD when induced in this way.

Lactate improves postoperative cognitive function through attenuating oxidative stress and neuroinflammation in aged mice via activating the SIRT1 pathway

Postoperative cognitive dysfunction (POCD) is a recognized clinical phenomenon characterized by cognitive impairment in patients following anesthesia and surgery, especially in the elderly. However, the pathogenesis of POCD remains unclear. In the last decades, lactate's neuroprotective properties have been increasingly mentioned. The study tested the hypothesis that lactate may attenuate the cognitive impairment induced by anesthesia and surgery in aged mice through SIRT1-dependent antioxidant and anti-inflammatory effects. We used 18-month-old C57BL/6 mice to establish the POCD animal model by exploratory laparotomy with isoflurane anesthesia. For the interventional study, mice were administered lactate, with or without the potent and selective SIRT1 inhibitor EX-527. Behavioral tests including open field (OF), Y maze and fear conditioning (FC) tests were performed from 4 to 7 days after anesthesia and surgery. Immunofluorescence staining and Western blot were employed to assess oxidative damage, activation of microglia and astrocytes, levels of proinflammatory cytokines, and the expression of plasticity-related proteins. Lactate treatment can ameliorate oxidative stress, neuroinflammation, and the decreased levels of plasticity-related proteins induced by anesthesia and surgery, ultimately improving cognitive impairment in aged mice. However, co-treatment with lactate and EX-527 diminished the beneficial effects. Our study indicates that the mechanisms underlying neuroprotective properties of lactate might be related to its antioxidant and anti-inflammatory effects, and improvement of hippocampal synaptic plasticity through activation of SIRT1 pathway.

T-regulatory cells and extracellular vesicles in Alzheimer's disease: New therapeutic concepts and hypotheses

Cell-based treatment has experienced exponential expansion in recent years in terms of clinical application and market share among pharmaceutical companies. When malignant cells in a healthy individual produce antigenic peptides derived from mutant or improperly synthesized proteins, the immune system attacks and kills the transforming cells. This process is carried out continuously by immune cells scanning the body for altered cells that could cause some harm. T-regulatory cells (Tregs), which preserve immunological tolerance and can exert neuroprotective benefits in numerous disorders, including animal models of Alzheimer's disease (AD), have demonstrated considerable therapeutic potential. Evidence also suggests that not only Tregs, but extracellular vesicles (EVs) are involved in a wide range of diseases, such as cellular homoeostasis, infection propagation, cancer development and heart disease, and have become a promisor cell-based therapeutic field too. Nevertheless, despite significant recent clinical and commercial breakthroughs, cell-based medicines still confront numerous challenges that hinder their general translation and commercialization. These challenges include, but are not limited to, choosing the best cell source, and creating a product that is safe, adequately viable, and fits the needs of individual patients and diseases. Here, we summarize what we know about Tregs and EVs and their potential therapeutic usage in AD.

The NF-κB pathway: Key players in neurocognitive functions and related disorders

Perioperative neurocognitive disorder (PND) is a common complication of surgical anesthesia, yet its precise etiology remains unclear. Neuroinflammation is a key feature of PND, influenced by both patient -related and surgical variables. The nuclear factor-κB (NF-κB) transcription factor family plays a critical role in regulating the body's immunological proinflammatory response, which is pivotal in the development of PND. Surgery and anesthesia trigger the activation of the NF-κB signaling pathway, leading to the initiation of inflammatory cascades, disruption of the blood-brain barrier, and neuronal injury. Immune cells and glial cells are central to these pathological processes in PND. Furthermore, this study explores the interactions between NF-κB and various signaling molecules, including Tlr4, P2X, α7-nAChR, ROS, HIF-1α, PI3K/Ak, MicroRNA, Circular RNA, and histone deacetylases, within the context of PND. Targeting NF-κB as a therapeutic approach for PND shows promise as a potential treatment strategy.

An Amino Acids and Dipeptide Injection Inhibits the TNF-α/HMGB1 Inflammatory Signaling Pathway to Reduce Pyroptosis and M1 Microglial Polarization in POCD Mice: the Gut to the Brain

Peripheral surgery-induced neural inflammation is a key pathogenic mechanism of postoperative cognitive dysfunction (POCD). However, the mechanism underlying neuroinflammation and associated neural injury remains elusive. Surgery itself can lead to gut damage, and the occurrence of POCD is accompanied by high levels of TNF-α in the serum and blood‒brain barrier (BBB) damage. Reductions in stress, inflammation and protein loss have been emphasized as strategies for enhanced recovery after surgery (ERAS). We designed an amino acids and dipeptide (AAD) formula for injection that could provide intestinal protection during surgery. Through the intraoperative infusion of AAD based on the ERAS concept, we aimed to explore the effect of AAD injection on POCD and its underlying mechanism from the gut to the brain. Here, we observed that AAD injection ameliorated neural injury in POCD, in addition to restoring the function of the intestinal barrier and BBB. We also found that TNF-α levels decreased in the ileum, blood and hippocampus. Intestinal barrier protectors and TNF-α inhibitors also alleviated neural damage. AAD injection treatment decreased HMGB1 production, pyroptosis, and M1 microglial polarization and increased M2 polarization. In vitro, AAD injection protected the impaired gut barrier and decreased TNF-α production, alleviating damage to the BBB by stimulating cytokine transport in the body. HMGB1 and Caspase-1 inhibitors decreased pyroptosis and M1 microglial polarization and increased M2 polarization to protect TNF-α-stimulated microglia in vitro. Collectively, these findings suggest that the gut barrier-TNF-α-BBB-HMGB1-Caspase-1 inflammasome-pyroptosis-M1 microglia pathway is a novel mechanism of POCD related to the gut-brain axis and that intraoperative AAD infusion is a potential treatment for POCD.

17β-Estradiol Ameliorates Postoperative Cognitive Dysfunction in Aged Mice via miR-138-5p/SIRT1/HMGB1 Pathway

BACKGROUND

Postoperative cognitive dysfunction (POCD) is a common neurological complication in older patients and correlated with adverse outcomes. 17β-estradiol treatment was reported to provide neuroprotective protection in various neurologic disorders, but whether it attenuated POCD was unknown. The purpose of this study was to explore the effects of 17β-estradiol treatment on POCD and its mechanisms.

METHODS

We generated a POCD model in 15-month-old mice via laparotomy, followed by subcutaneous injection of 17β-estradiol, intraperitoneal injection of EX527 (a Sirtuin 1 [SIRT1] inhibitor), or bilateral hippocampal injection of miR-138-5p-agomir. Morris water maze test and open field test were applied to evaluate the cognitive function. The neuronal apoptosis in the hippocampus was detected using the terminal transferase dUTP nick end labeling assay. Meanwhile, the levels of interleukin-1β (IL-1β) and microglia activation were measured by enzymelinked immunosorbent assay and immunofluorescence, respectively. Western blot was utilized to assess the expression of SIRT1 and high mobility group box 1 (HMGB1) protein, and gene expression of miR-138-5p was determined through quantitative real-time polymerase chain reaction.

RESULTS

Behavioral tests showed that 17β-estradiol treatment improved cognitive function in aged POCD mice. In addition, 17β-estradiol attenuated neuronal apoptosis and microglia activation as well as IL-1β expression in the hippocampus. Nonetheless, injection with EX527 abolished the beneficial impacts of 17β-estradiol against POCD. Furthermore, miR-138-5p was verified to bind with SIRT1, which regulated the expression of HMGB1. After treatment with 17β-estradiol, miR-138-5p expression was reduced in the hippocampus, and the neuroprotective influence of 17β-estradiol on aged POCD mice was reversed after administration of miR-138-5p-agomir.

CONCLUSIONS

17β-estradiol treatment exerted neuroprotection effects on POCD in aged mice, which might be relevant to alleviating neuroinflammation via miR-138-5p/SIRT1/HMGB1 pathway.

Exercise-conditioned plasma ameliorates postoperative cognitive dysfunction by activating hippocampal cholinergic circuit and enhancing BDNF/TrkB signaling

BACKGROUND

Postoperative cognitive dysfunction (POCD) is a prevalent complication following anesthesia and surgery, particularly in the elderly, leading to increased mortality and reduced quality of life. Despite its prevalence, there are no effective clinical treatments. Exercise has shown cognitive benefits in aging and various diseases, which can be transferred to sedentary animals through plasma. However, it is unclear if exercise-conditioned plasma can replicate these benefits in the context of POCD.

METHODS

Sixteen-month-old male C57BL/6J mice underwent 30 days of voluntary running wheel training or received systemic administration of exercise-conditioned plasma, followed by tibial fracture surgery under general anesthesia at 17 months of age. Cognitive performance, hippocampal synaptic deficits, neuroinflammation, BDNF/TrkB signaling, and medial septum (MS)-hippocampal cholinergic activity were evaluated through immunohistochemical staining, transmission electron microscopy, Western blotting, and biochemical assays. To investigate the role of hippocampal BDNF signaling and cholinergic activity in the therapeutic effects, the TrkB antagonist ANA-12 and the cholinergic receptor muscarinic 1 (CHRM1) antagonist trihexyphenidyl (THP) were administered via intraperitoneal injection, and adeno-associated virus (AAV) vectors expressing Chrm1 shRNA were delivered via intrahippocampal stereotaxic microinjection.

RESULTS

Exercise-conditioned plasma mimicked the benefits of exercise, alleviating cognitive decline induced by anesthesia/surgery, restoring hippocampal synapse formation and levels of regulators for synaptic plasticity, inhibiting neuroinflammatory responses to surgery by microglia and astrocytes, augmenting BDNF production and TrkB phosphorylation in hippocampal neurons, astrocytes, and microglia, upregulating MS expression of choline acetyltransferase (CHAT) and hippocampal expression of CHRM1 in neurons and astrocytes, and enhancing hippocampal cholinergic innervation and acetylcholine release. Conversely, ANA-12 administration blocked TrkB activation and reduced the protective effects on cognition, synaptic deficits, and neuroinflammatory reactivity of glial cells post-surgery. Similarly, THP administration or intrahippocampal delivery of AAV-Chrm1 shRNA inhibited the activation of the hippocampal cholinergic circuit by exercise plasma, negating the cognitive and neuropathological benefits and reducing BDNF/TrkB signaling enhancements.

CONCLUSION

Exercise-conditioned plasma can replicate the protective effects of exercise against anesthesia/surgery-induced neuroinflammation, synaptic, and cognitive impairments, at least partly, through CHRM1-dependent regulation of hippocampal cholinergic activity and BDNF/TrkB signaling.

Tryptophan-rich diet and its effects on Htr7+ Tregs in alleviating neuroinflammation and cognitive impairment induced by lipopolysaccharide

BACKGROUND

Neuroinflammation is a vital pathogenic mechanism for neurodegenerative diseases such as Alzheimer's, schizophrenia, and age-related cognitive decline. Regulatory T cells (Tregs) exhibit potent anti-inflammatory properties and can modulate neurodegenerative diseases arising from central nervous system inflammatory responses. However, the role of Tregs in neuroinflammation-related cognitive dysfunction remains unclear. It is highly plausible that Htr7+ Tregs expressing unique genes associated with the nervous system, including the Htr7 gene encoding the serotonin receptor 5-HT7, play a pivotal role.

METHODS

Mice were given a tryptophan-rich diet (with a tryptophan content of 0.6%) or a normal diet (with a tryptophan content of 0.16%). The neuroinflammation-mediated cognitive dysfunction model was established by intracerebroventricular injection of lipopolysaccharide (LPS) in 8-week-old C57BL/6J mice. The activation and infiltration of Tregs were measured using flow cytometry. Primary Tregs were cocultured separately with primary CD8+ T cells and primary microglia for in vitro validation of the impact of 5-HT and 5-HT7 receptor on Tregs. Prior to their transfer into recombination activating gene 1 (Rag1-/-) mice, Tregs were ex vivo transfected with lentivirus to knock down the expression of Htr7.

RESULTS

In this study, the tryptophan-rich diet was found to reverse LPS-induced cognitive impairment and reduce the levels of 5-HT in peripheral blood. The tryptophan-rich diet led to increased levels of 5-HT in peripheral blood, which in turn promoted the proliferation and activation of Htr7+ Tregs. Additionally, the tryptophan-rich diet was also shown to attenuate LPS-mediated neuroinflammation by activating Htr7+ Tregs. Furthermore, 5-HT and 5-HT7 receptor were found to enhance the immunosuppressive effect of Tregs on CD8+ T cells and microglia. In Rag1-/- mice, Htr7+ Tregs were shown to alleviate LPS-induced neuroinflammation and cognitive impairment.

CONCLUSIONS

Our research revealed the ability of Htr7+ Tregs to mitigate neuroinflammation and prevent neuronal damage by suppressing the infiltration of CD8+ T cells into the brain and excessive activation of microglia, thereby ameliorating LPS-induced cognitive impairment. These insights may offer novel therapeutic targets involving Tregs for neuroinflammation and cognitive impairment.

Cellular Components of the Blood-Brain Barrier and Their Involvement in Aging-Associated Cognitive Impairment

Human life expectancy has been significantly extended, which poses major challenges to our healthcare and social systems. Aging-associated cognitive impairment is attributed to endothelial dysfunction in the cardiovascular system and neurological dysfunction in the central nervous system. The central nervous system is considered an immune-privileged tissue due to the exquisite protection provided by the blood-brain barrier. The present review provides an overview of the structure and function of blood-brain barrier, extending the cell components of blood-brain barrier from endothelial cells and pericytes to astrocytes, perivascular macrophages and oligodendrocyte progenitor cells. In particular, the pathological changes in the blood-brain barrier in aging, with special focus on the underlying mechanisms and molecular changes, are presented. Furthermore, the potential preventive/therapeutic strategies against aging-associated blood-brain barrier disruption are discussed.

Brain-Bone Crosstalk in a Murine Polytrauma Model Promotes Bone Remodeling but Impairs Neuromotor Recovery and Anxiety-Related Behavior

Traumatic brain injury (TBI) and long bone fractures are a common injury pattern in polytrauma patients and modulate each other's healing process. As only a limited number of studies have investigated both traumatic sites, we tested the hypothesis that brain-bone polytrauma mutually impacts neuro- and osteopathological outcomes. Adult female C57BL/6N mice were subjected to controlled cortical impact (CCI), and/or osteosynthetic stabilized femoral fracture (FF), or sham surgery. Neuromotor and behavioral impairments were assessed by neurological severity score, open field test, rotarod test, and elevated plus maze test. Brain and bone tissues were processed 42 days after trauma. CCI+FF polytrauma mice had increased bone formation as compared to FF mice and increased mRNA expression of bone sialoprotein (BSP). Bone fractures did not aggravate neuropathology or neuroinflammation assessed by cerebral lesion size, hippocampal integrity, astrocyte and microglia activation, and gene expression. Behavioral assessments demonstrated an overall impaired recovery of neuromotor function and persistent abnormalities in anxiety-related behavior in polytrauma mice. This study shows enhanced bone healing, impaired neuromotor recovery and anxiety-like behavior in a brain-bone polytrauma model. However, bone fractures did not aggravate TBI-evoked neuropathology, suggesting the existence of outcome-relevant mechanisms independent of the extent of brain structural damage and neuroinflammation.

COVID-19 vaccination may prevent postoperative delirium in elderly patients undergoing elective non-cardiac surgery: The PNDRFAP and PNDABLE studies

Background

Postoperative delirium (POD) often occurs in elderly patients after surgery. We conducted two clinical studies to determine whether COVID-19 vaccination has a protective effect on POD and to explore the role of CSF biomarkers in this process.

Methods

We conducted two clinical studies, Perioperative Neurocognitive Disorder Risk Factor and Prognosis (PNDRFAP) and Perioperative Neurocognitive Disorder and Biomarker Lifestyle (PNDABLE), in which patients more than or equal to 65 years old who have had elective non-cardiac surgery were enrolled. The preoperative cognitive status of patients were evaluated by Mini-Mental State Examination (MMSE) one day preoperatively. Confusion Assessment Method (CAM) was used to diagnose POD. We used the mediation model to analyze the relationship between CSF biomarkers, COVID-19 vaccination and POD, as well as Dynamic Nomogram to calculate the incidence of Non-Postoperative Delirium (NPOD). The main outcome of these studies was the incidence of POD during seven days postoperatively or before discharge, which was assessed by CAM.

Results

In the final, 705 participants were enrolled in the PNDRFAP study, and 638 patients in the PNDABLE. In both studies, we found that the occurrence of POD was lower in patients who had injected COVID-19 vaccination before surgery compared with those without vaccination (PNDRFAP: 10.20 % [21/205] vs 25.80 % [129/500], P < 0.001; PNDABLE: 2.40 % [4/164] vs 34.60 % [164/474], P < 0.001). Mediation analysis showed that the protective effect of preoperative COVID-19 vaccine on POD was significantly mediated by CSF Aβ42 (proportion = 17.56 %), T-tau (proportion = 19.64 %), Aβ42/T-tau (proportion = 29.67 %), and Aβ42/P-tau (proportion = 12.26 %).

Conclusions

COVID-19 vaccine is a protective factor for POD in old patients, which is associated with CSF biomarkers.

Integrative analysis of circRNA networks in postoperative cognitive dysfunction

OBJECTIVE

In the quest to decipher the molecular intricacies of Postoperative Cognitive Dysfunction (POCD), this study focused on circular RNA (circRNA) and their regulatory networks.

MATERIALS AND METHODS

Analyzing the Gene Expression Omnibus Series (GSE) 147277 dataset, we pinpointed 10 differentially expressed circRNAs linked to POCD.

RESULTS

The ensuing competing endogenous RNA (ceRNA) network, featuring pivotal players like Homo sapiens(hsa)_circ_0003424 and hsa-miR-193b-5p, provided a comprehensive understanding of the molecular players at play in POCD.

CONCLUSION

Additionally, the Protein-Protein Interaction (PPI) network spotlighted 10 core Hub genes, including phosphatase and tensin homolog (PTEN) and signal transducer and activator of transcription 3(STAT3), shedding light on potential therapeutic targets.

Post-operative cognitive dysfunction is exacerbated by high-fat diet via TLR4 and prevented by dietary DHA supplementation

Post-operative cognitive dysfunction (POCD) is an abrupt decline in neurocognitive function arising shortly after surgery and persisting for weeks to months, increasing the risk of dementia diagnosis. Advanced age, obesity, and comorbidities linked to high-fat diet (HFD) consumption such as diabetes and hypertension have been identified as risk factors for POCD, although underlying mechanisms remain unclear. We have previously shown that surgery alone, or 3-days of HFD can each evoke sufficient neuroinflammation to cause memory deficits in aged, but not young rats. The aim of the present study was to determine if HFD consumption before surgery would potentiate and prolong the subsequent neuroinflammatory response and memory deficits, and if so, to determine the extent to which these effects depend on activation of the innate immune receptor TLR4, which both insults are known to stimulate. Young-adult (3mo) & aged (24mo) male F344xBN F1 rats were fed standard chow or HFD for 3-days immediately before sham surgery or laparotomy. In aged rats, the combination of HFD and surgery caused persistent deficits in contextual memory and cued-fear memory, though it was determined that HFD alone was sufficient to cause the long-lasting cued-fear memory deficits. In young adult rats, HFD + surgery caused only cued-fear memory deficits. Elevated proinflammatory gene expression in the hippocampus of both young and aged rats that received HFD + surgery persisted for at least 3-weeks after surgery. In a separate experiment, rats were administered the TLR4-specific antagonist, LPS-RS, immediately before HFD onset, which ameliorated the HFD + surgery-associated neuroinflammation and memory deficits. Similarly, dietary DHA supplementation for 4 weeks prior to HFD onset blunted the neuroinflammatory response to surgery and prevented development of persistent memory deficits. These results suggest that HFD 1) increases risk of persistent POCD-associated memory impairments following surgery in male rats in 2) a TLR4-dependent manner, which 3) can be targeted by DHA supplementation to mitigate development of persistent POCD.

Glycolytic enzyme PFKFB3 regulates sphingosine 1-phosphate receptor 1 in proangiogenic glomerular endothelial cells under diabetic condition

Glomerular angiogenesis is a characteristic feature of diabetic nephropathy (DN). Enhanced glycolysis plays a crucial role in angiogenesis. The present study was designed to investigate the role of glycolysis in glomerular endothelial cells (GECs) in a mouse model of DN. Mouse renal cortex and isolated glomerular cells were collected for single-cell and RNA sequencing. Cultured GECs were exposed to high glucose in the presence (proangiogenic) and absence of a vascular sprouting regimen. MicroRNA-590-3p was delivered by lipofectamine in vivo and in vitro. In the present study, a subgroup of GECs with proangiogenic features was identified in diabetic kidneys by using sequencing analyses. In cultured proangiogenic GECs, high glucose increased glycolysis and phosphofructokinase/fructose bisphosphatase 3 (PFKFB3) protein expression, which were inhibited by overexpressing miRNA-590-3p. Mimics of miRNA-590-3p also increased receptor for sphingosine 1-phosphate (S1pR1) expression, an angiogenesis regulator, in proangiogenic GECs challenged with high glucose. Inhibition of PFKFB3 by pharmacological and genetic approaches upregulated S1pR1 protein in vitro. Mimics of miRNA-590-3p significantly reduced migration and angiogenic potential in proangiogenic GECs challenged with high glucose. Ten-week-old type 2 diabetic mice had elevated urinary albumin levels, reduced renal cortex miRNA-590-3p expression, and disarrangement of glomerular endothelial cell fenestration. Overexpressing miRNA-590-3p via perirenal adipose tissue injection restored endothelial cell fenestration and reduced urinary albumin levels in diabetic mice. Therefore, the present study identifies a subgroup of GECs with proangiogenic features in mice with DN. Local administration of miRNA-590-3p mimics reduces glycolytic rate and upregulates S1pR1 protein expression in proangiogenic GECs. The protective effects of miRNA-590-3p provide therapeutic potential in DN treatment.NEW & NOTEWORTHY Proangiogenetic glomerular endothelial cells (GECs) are activated in diabetic nephropathy. High glucose upregulates glycolytic enzyme phosphofructokinase/fructose bisphosphatase 3 (PFKFB3) in proangiogenetic cells. PFKFB3 protects the glomerular filtration barrier by targeting endothelial S1pR1. MiRNA-590-3p restores endothelial cell function and mitigates diabetic nephropathy.