-
Theranostics 2022Microvascular complication is a major cause of morbidity and mortality among the patients with diabetes. Pericyte dysfunction is the predominant pathological...
Microvascular complication is a major cause of morbidity and mortality among the patients with diabetes. Pericyte dysfunction is the predominant pathological manifestation of microvascular complication. -methyladenosine (mA) serves as the most prevalent modification in eukaryotic mRNAs. However, the role of mA RNA modification in pericyte dysfunction is still unclear. Quantitative polymerase chain reactions and western blots were conducted to detect the change of mA RNA modification in pericytes and mouse retinas following diabetic stress. MTT assay, transwell migration assay, caspase 3/7 activity assay, calcein-AM/propidium iodide (PI) staining, and TUNEL staining were conducted to determine the role of METTL3 in pericyte biology . Retinal trypsin digestion, vascular permeability assay, and IB4-NG2 double immunofluorescent staining were conducted to determine the role of METTL3 in retinal pericyte dysfunction and vascular complication. RNA sequencing, RNA pull-down assays and immunoblots were conducted to clarify the mechanism of METTL3-mediated pericyte dysfunction and vascular complication. The levels of mA RNA methylation were significantly up-regulated in pericytes and mouse retinas following diabetic stress, which were caused by increased expression of METTL3. METTL3 regulated the viability, proliferation, and differentiation of pericytes . Specific depletion of METTL3 in pericytes suppressed diabetes-induced pericyte dysfunction and vascular complication . METTL3 overexpression impaired pericyte function by repressing PKC-η, FAT4, and PDGFRA expression, which was mediated by YTHDF2-dependent mRNA decay. METTL3-mediated mA methylation epigenetically regulates diabetes-induced pericyte dysfunction. METTL3-YTHDF2-PKC-η/FAT4/PDGFRA signaling axis could be therapeutically targeted for treating microvascular complications.
Topics: Animals; Cell Line; Diabetes Mellitus; Diabetic Retinopathy; Humans; Methyltransferases; Mice; Mice, Inbred C57BL; Mice, Knockout; Pericytes
PubMed: 34987645
DOI: 10.7150/thno.63441 -
Nature Sep 2020Signalling between cells of the neurovascular unit, or neurovascular coupling, is essential to match local blood flow with neuronal activity. Pericytes interact with...
Signalling between cells of the neurovascular unit, or neurovascular coupling, is essential to match local blood flow with neuronal activity. Pericytes interact with endothelial cells and extend processes that wrap capillaries, covering up to 90% of their surface area. Pericytes are candidates to regulate microcirculatory blood flow because they are strategically positioned along capillaries, contain contractile proteins and respond rapidly to neuronal stimulation, but whether they synchronize microvascular dynamics and neurovascular coupling within a capillary network was unknown. Here we identify nanotube-like processes that connect two bona fide pericytes on separate capillary systems, forming a functional network in the mouse retina, which we named interpericyte tunnelling nanotubes (IP-TNTs). We provide evidence that these (i) have an open-ended proximal side and a closed-ended terminal (end-foot) that connects with distal pericyte processes via gap junctions, (ii) carry organelles including mitochondria, which can travel along these processes, and (iii) serve as a conduit for intercellular Ca waves, thus mediating communication between pericytes. Using two-photon microscope live imaging, we demonstrate that retinal pericytes rely on IP-TNTs to control local neurovascular coupling and coordinate light-evoked responses between adjacent capillaries. IP-TNT damage following ablation or ischaemia disrupts intercellular Ca waves, impairing blood flow regulation and neurovascular coupling. Notably, pharmacological blockade of Ca influx preserves IP-TNTs, rescues light-evoked capillary responses and restores blood flow after reperfusion. Our study thus defines IP-TNTs and characterizes their critical role in regulating neurovascular coupling in the living retina under both physiological and pathological conditions.
Topics: Animals; Brain Ischemia; Calcium; Calcium Signaling; Capillaries; Cell Communication; Female; Gap Junctions; Hemodynamics; Male; Mice; Mitochondria; Nanotubes; Neurovascular Coupling; Pericytes; Retina
PubMed: 32788726
DOI: 10.1038/s41586-020-2589-x -
Nature Communications May 2022The cardiac vascular and perivascular niche are of major importance in homeostasis and during disease, but we lack a complete understanding of its cellular heterogeneity...
The cardiac vascular and perivascular niche are of major importance in homeostasis and during disease, but we lack a complete understanding of its cellular heterogeneity and alteration in response to injury as a major driver of heart failure. Using combined genetic fate tracing with confocal imaging and single-cell RNA sequencing of this niche in homeostasis and during heart failure, we unravel cell type specific transcriptomic changes in fibroblast, endothelial, pericyte and vascular smooth muscle cell subtypes. We characterize a specific fibroblast subpopulation that exists during homeostasis, acquires Thbs4 expression and expands after injury driving cardiac fibrosis, and identify the transcription factor TEAD1 as a regulator of fibroblast activation. Endothelial cells display a proliferative response after injury, which is not sustained in later remodeling, together with transcriptional changes related to hypoxia, angiogenesis, and migration. Collectively, our data provides an extensive resource of transcriptomic changes in the vascular niche in hypertrophic cardiac remodeling.
Topics: Endothelial Cells; Fibroblasts; Heart Failure; Humans; Myocytes, Smooth Muscle; Pericytes
PubMed: 35641541
DOI: 10.1038/s41467-022-30682-0 -
Nature Neuroscience May 2021The majority of the brain's vasculature is composed of intricate capillary networks lined by capillary pericytes. However, it remains unclear whether capillary pericytes...
The majority of the brain's vasculature is composed of intricate capillary networks lined by capillary pericytes. However, it remains unclear whether capillary pericytes influence blood flow. Using two-photon microscopy to observe and manipulate brain capillary pericytes in vivo, we find that their optogenetic stimulation decreases lumen diameter and blood flow, but with slower kinetics than similar stimulation of mural cells on upstream pial and precapillary arterioles. This slow vasoconstriction was inhibited by the clinically used vasodilator fasudil, a Rho-kinase inhibitor that blocks contractile machinery. Capillary pericytes were also slower to constrict back to baseline following hypercapnia-induced dilation, and slower to dilate towards baseline following optogenetically induced vasoconstriction. Optical ablation of single capillary pericytes led to sustained local dilation and a doubling of blood cell flux selectively in capillaries lacking pericyte contact. These data indicate that capillary pericytes contribute to basal blood flow resistance and slow modulation of blood flow throughout the brain.
Topics: Animals; Brain; Capillaries; Cerebrovascular Circulation; Hemodynamics; Mice; Pericytes
PubMed: 33603231
DOI: 10.1038/s41593-020-00793-2 -
Military Medical Research Mar 2023Vascular hyporeactivity and leakage are key pathophysiologic features that produce multi-organ damage upon sepsis. We hypothesized that pericytes, a group of pluripotent...
BACKGROUND
Vascular hyporeactivity and leakage are key pathophysiologic features that produce multi-organ damage upon sepsis. We hypothesized that pericytes, a group of pluripotent cells that maintain vascular integrity and tension, are protective against sepsis via regulating vascular reactivity and permeability.
METHODS
We conducted a series of in vivo experiments using wild-type (WT), platelet-derived growth factor receptor beta (PDGFR-β)-Cre + mT/mG transgenic mice and Tie2-Cre + Cx43 mice to examine the relative contribution of pericytes in sepsis, either induced by cecal ligation and puncture (CLP) or lipopolysaccharide (LPS) challenge. In a separate set of experiments with Sprague-Dawley (SD) rats, pericytes were depleted using CP-673451, a selective PDGFR-β inhibitor, at a dosage of 40 mg/(kg·d) for 7 consecutive days. Cultured pericytes, vascular endothelial cells (VECs) and vascular smooth muscle cells (VSMCs) were used for mechanistic investigations. The effects of pericytes and pericyte-derived microvesicles (PCMVs) and candidate miRNAs on vascular reactivity and barrier function were also examined.
RESULTS
CLP and LPS induced severe injury/loss of pericytes, vascular hyporeactivity and leakage (P < 0.05). Transplantation with exogenous pericytes protected vascular reactivity and barrier function via microvessel colonization (P < 0.05). Cx43 knockout in either pericytes or VECs reduced pericyte colonization in microvessels (P < 0.05). Additionally, PCMVs transferred miR-145 and miR-132 to VSMCs and VECs, respectively, exerting a protective effect on vascular reactivity and barrier function after sepsis (P < 0.05). miR-145 primarily improved the contractile response of VSMCs by activating the sphingosine kinase 2 (Sphk2)/sphingosine-1-phosphate receptor (S1PR)1/phosphorylation of myosin light chain 20 pathway, whereas miR-132 effectively improved the barrier function of VECs by activating the Sphk2/S1PR2/zonula occludens-1 and vascular endothelial-cadherin pathways.
CONCLUSIONS
Pericytes are protective against sepsis through regulating vascular reactivity and barrier function. Possible mechanisms include both direct colonization of microvasculature and secretion of PCMVs.
Topics: Animals; Mice; Rats; Capillary Permeability; Connexin 43; Endothelial Cells; Lipopolysaccharides; MicroRNAs; Pericytes; Rats, Sprague-Dawley; Sepsis
PubMed: 36907884
DOI: 10.1186/s40779-023-00442-2 -
Nature Reviews. Cardiology Feb 2024Millions of cardiomyocytes die immediately after myocardial infarction, regardless of whether the culprit coronary artery undergoes prompt revascularization. Residual... (Review)
Review
Millions of cardiomyocytes die immediately after myocardial infarction, regardless of whether the culprit coronary artery undergoes prompt revascularization. Residual ischaemia in the peri-infarct border zone causes further cardiomyocyte damage, resulting in a progressive decline in contractile function. To date, no treatment has succeeded in increasing the vascularization of the infarcted heart. In the past decade, new approaches that can target the heart's highly plastic perivascular niche have been proposed. The perivascular environment is populated by mesenchymal progenitor cells, fibroblasts, myofibroblasts and pericytes, which can together mount a healing response to the ischaemic damage. In the infarcted heart, pericytes have crucial roles in angiogenesis, scar formation and stabilization, and control of the inflammatory response. Persistent ischaemia and accrual of age-related risk factors can lead to pericyte depletion and dysfunction. In this Review, we describe the phenotypic changes that characterize the response of cardiac pericytes to ischaemia and the potential of pericyte-based therapy for restoring the perivascular niche after myocardial infarction. Pericyte-related therapies that can salvage the area at risk of an ischaemic injury include exogenously administered pericytes, pericyte-derived exosomes, pericyte-engineered biomaterials, and pharmacological approaches that can stimulate the differentiation of constitutively resident pericytes towards an arteriogenic phenotype. Promising preclinical results from in vitro and in vivo studies indicate that pericytes have crucial roles in the treatment of coronary artery disease and the prevention of post-ischaemic heart failure.
Topics: Humans; Pericytes; Myocardial Infarction; Myocytes, Cardiac; Ischemia; Coronary Vessels
PubMed: 37542118
DOI: 10.1038/s41569-023-00913-y -
Cancer Research Oct 2022The tumor microenvironment plays a central role in cancer initiation and progression. CD248 is expressed in tumor-associated stromal cells, particularly fibroblasts and...
UNLABELLED
The tumor microenvironment plays a central role in cancer initiation and progression. CD248 is expressed in tumor-associated stromal cells, particularly fibroblasts and pericytes. Exploring the function of CD248 has the potential to provide biological insights into tumor-supportive stroma and potential therapeutic targets. Here, we investigated the role of stromal CD248 in lung cancer. In orthotopic lung cancer transplantation models, tumor volume, density of vessels and pericytes, and functionality of tumor vessels were all lower in mice lacking Cd248 (Cd248LacZ/LacZ) compared with Cd248 wild-type or haploinsufficient mice. Two angiogenic factors, OPN and SERPINE1, were decreased in Cd248LacZ/LacZ pericytes, and supplementation with both factors rescued their proliferation and endothelial cell tube formation-promoting ability. Mechanistically, Wnt/β-catenin signaling induced Opn and Serpine1 expression and was suppressed in Cd248LacZ/LacZ pericytes. CD248 interacted with Wnt pathway repressors IGFBP4 and LGALS3BP, leading to increased Wnt/β-catenin signaling. Correspondingly, administration of a β-catenin inhibitor in Cd248+/LacZ mice mimicked the effect of Cd248 loss and blocked the growth of transplanted lung tumor cells that were resistant to this inhibitor in vitro. In addition, CD248+ pericytes coexpressed OPN and SERPINE1 and correlated with increased tumor size in human lung cancer. Additionally, high expression of CD248, OPN, and SERPINE1 was associated with poor survival in lung cancer patients. In summary, CD248 derepresses Wnt signaling and upregulates OPN and SERPINE1 in pericytes, resulting in enhanced angiogenesis and lung cancer growth. This novel axis of CD248-Wnt signaling-angiogenic factors in pericytes provides a potential target for lung cancer therapy.
SIGNIFICANCE
These findings demonstrate that CD248 maintains pericyte function in lung cancer through the Wnt signaling pathway and present CD248 as a potential therapeutic target.
Topics: Animals; Antigens, CD; Antigens, Neoplasm; Humans; Lung Neoplasms; Mice; Neovascularization, Pathologic; Pericytes; Tumor Microenvironment; Wnt Signaling Pathway; beta Catenin
PubMed: 35950912
DOI: 10.1158/0008-5472.CAN-22-1695 -
The EMBO Journal May 2022Endothelial cells differ from other cell types responsible for the formation of the vascular wall in their unusual reliance on glycolysis for most energy needs, which...
Endothelial cells differ from other cell types responsible for the formation of the vascular wall in their unusual reliance on glycolysis for most energy needs, which results in extensive production of lactate. We find that endothelium-derived lactate is taken up by pericytes, and contributes substantially to pericyte metabolism including energy generation and amino acid biosynthesis. Endothelial-pericyte proximity is required to facilitate the transport of endothelium-derived lactate into pericytes. Inhibition of lactate production in the endothelium by deletion of the glucose transporter-1 (GLUT1) in mice results in loss of pericyte coverage in the retina and brain vasculatures, leading to the blood-brain barrier breakdown and increased permeability. These abnormalities can be largely restored by oral lactate administration. Our studies demonstrate an unexpected link between endothelial and pericyte metabolisms and the role of endothelial lactate production in the maintenance of the blood-brain barrier integrity. In addition, our observations indicate that lactate supplementation could be a useful therapeutic approach for GLUT1 deficiency metabolic syndrome patients.
Topics: Animals; Blood-Brain Barrier; Endothelial Cells; Endothelium; Glucose Transporter Type 1; Humans; Lactic Acid; Mice; Pericytes
PubMed: 35243676
DOI: 10.15252/embj.2021109890 -
Cells Jul 2023Pericytes are specialized cells located in close proximity to endothelial cells within the microvasculature. They play a crucial role in regulating blood flow,... (Review)
Review
Pericytes are specialized cells located in close proximity to endothelial cells within the microvasculature. They play a crucial role in regulating blood flow, stabilizing vessel walls, and maintaining the integrity of the blood-brain barrier. The loss of pericytes has been associated with the development and progression of various diseases, such as diabetes, Alzheimer's disease, sepsis, stroke, and traumatic brain injury. This review examines the detection of pericyte loss in different diseases, explores the methods employed to assess pericyte coverage, and elucidates the potential mechanisms contributing to pericyte loss in these pathological conditions. Additionally, current therapeutic strategies targeting pericytes are discussed, along with potential future interventions aimed at preserving pericyte function and promoting disease mitigation.
Topics: Humans; Pericytes; Endothelial Cells; Blood-Brain Barrier; Stroke; Brain Injuries, Traumatic
PubMed: 37566011
DOI: 10.3390/cells12151931 -
The Journal of Clinical Investigation Jul 2020Diabetic retinopathy (DR) is the leading cause of blindness in working-age adults. Vascular pericyte degeneration is the predominant clinical manifestation of DR, yet...
Diabetic retinopathy (DR) is the leading cause of blindness in working-age adults. Vascular pericyte degeneration is the predominant clinical manifestation of DR, yet the mechanism governing pericyte degeneration is poorly understood. Circular RNAs (circRNAs) play important roles in multiple biological processes and disease progression. Here, we investigated the role of circRNA in pericyte biology and diabetes-induced retinal vascular dysfunction. cZNF532 expression was upregulated in pericytes under diabetic stress, in the retinal vessels of a diabetic murine model, and in the vitreous humor of diabetic patients. cZNF532 silencing reduced the viability, proliferation, and differentiation of pericytes and suppressed the recruitment of pericytes toward endothelial cells in vitro. cZNF532 regulated pericyte biology by acting as a miR-29a-3p sponge and inducing increased expression of NG2, LOXL2, and CDK2. Knockdown of cZNF532 or overexpression of miR-29a-3p aggravated streptozotocin-induced retinal pericyte degeneration and vascular dysfunction. By contrast, overexpression of cZNF532 or inhibition of miR-29a-3p ameliorated human diabetic vitreous-induced retinal pericyte degeneration and vascular dysfunction. Collectively, these data identify a circRNA-mediated mechanism that coordinates pericyte biology and vascular homeostasis in DR. Induction of cZNF532 or antagonism of miR-29a-3p is an exploitable therapeutic approach for the treatment of DR.
Topics: Animals; Cell Line; Diabetic Retinopathy; Eye Proteins; Humans; Mice; MicroRNAs; Pericytes; RNA, Circular; Retinal Vessels
PubMed: 32343678
DOI: 10.1172/JCI123353