To investigate the sex-dependent differentiation of Sox10 cells and their response to pathological conditions such as lipopolysaccharide (LPS) exposure or ischemia, we utilized Sox10 Cre-ERT2, tdTomato mice. Tamoxifen administration induced the expression of red fluorescent protein (RFP) in these cells, facilitating their subsequent tracking and analysis after LPS injection and ischemia via immunofluorescence staining. Propidium iodide (PI) was injected to label necrotic cells following LPS administration. We found that the conversion of Sox10 cells to pericytes in female mice was significantly higher than in male mice, especially in those exposed to LPS. After LPS injection, the number of PI+ necrotic cells were significantly greater in females than in males. Moreover, RFP+ cells did not co-localize with glial fibrillary acidic protein (GFAP) or cluster of differentiation 11b (CD11b). Similarly, after brain ischemia, RFP+ cells did not express cluster of differentiation 13 (CD13), neuronal nuclei (NeuN), GFAP, or ionised calcium binding adaptor molecule 1 (Iba-1). These findings indicate that the conversion of Sox10 cells to pericytes following LPS exposure is sex-dependent, with neither male nor female groups showing differentiation into other cell types after LPS exposure or under ischemic conditions. The differences in LPS-induced necrosis of pericytes between sexes may explain the variations in the conversion of Sox10 cells to pericytes in both sexes.

肿瘤微环境对结直肠癌患者的预后和治疗作用至关重要，肿瘤血管对结直肠癌的影响也日益受到重视。近年研究发现，新生肿瘤血管与正常血管结构功能均具有较大差异，这种新生血管的内皮细胞形态异常，周细胞松散附着或缺失以及基底膜的异常增厚或完全缺失，出现迂曲、囊性扩张等异常血管结构，从而抑制药物递送，而血管正常化后可恢复血管功能，目前将周细胞覆盖率、内皮细胞及基底膜渗漏作为评估血管正常化的评价指标。新近研究发现结直肠癌组织中血管的内皮细胞、周细胞及基底膜对肿瘤具有双向调控作用，本文综述血管相关结构对结直肠癌的具体影响，以及周细胞覆盖率和血管通透性作为评价肿瘤血管正常化的理论依据，总结了血管正常化的相关检测指标及对患者相关治疗的积极影响，使患者因血管正常化受益的同时尽可能地减少其不良影响。.

UNASSIGNED: Diabetes is closely linked to hearing loss, yet the exact mechanisms remain unclear. Cochlear stria vascularis and pericytes (PCs) are crucial for hearing. This study investigates whether high glucose induces apoptosis in the cochlear stria vascularis and pericytes via elevated ROS levels due to oxidative stress, impacting hearing loss.
UNASSIGNED: We established a type II diabetes model in C57BL/6J mice and used auditory brainstem response (ABR), Evans blue staining, HE staining, immunohistochemistry, and immunofluorescence to observe changes in hearing, blood-labyrinth barrier (BLB) permeability, stria vascularis morphology, and apoptosis protein expression. Primary cultured stria vascularis pericytes were subjected to high glucose, and apoptosis levels were assessed using flow cytometry, Annexin V-FITC, Hoechst 33342 staining, Western blot, Mitosox, and JC-1 probes.
UNASSIGNED: Diabetic mice showed decreased hearing thresholds, reduced stria vascularis density, increased oxidative stress, cell apoptosis, and decreased antioxidant levels. High glucose exposure increased apoptosis and ROS content in pericytes, while mitochondrial membrane potential decreased, with AIF and cytochrome C (CytC) released from mitochondria to the cytoplasm. Adding oxidative scavengers reduced AIF and CytC release, decreasing pericyte apoptosis.
UNASSIGNED: Hyperglycemia may induce mitochondrial apoptosis of cochlear stria vascularis pericytes through oxidative stress.

BACKGROUND: Excessive pericyte coverage promotes tumor growth, and a downregulation may solve this dilemma. Due to the double-edged sword role of vascular pericytes in tumor microenvironment (TME), indiscriminately decreasing pericyte coverage by imatinib causes poor treatment outcomes. Here, we optimized the use of imatinib in a colorectal cancer (CRC) model in high pericyte-coverage status, and revealed the value of multiparametric magnetic resonance imaging (mpMRI) at 9.4T in monitoring treatment-related changes in pericyte coverage and the TME.
METHODS: CRC xenograft models were evaluated by histological vascular characterizations and mpMRI. Mice with the highest pericyte coverage were treated with imatinib or saline; then, vascular characterizations, tumor apoptosis and HIF-1α level were analyzed histologically, and alterations in the expression of Bcl-2/bax pathway were assessed through qPCR. The effects of imatinib were monitored by dynamic contrast-enhanced (DCE)-, diffusion-weighted imaging (DWI)- and amide proton transfer chemical exchange saturation transfer (APT CEST)-MRI at 9.4T.
RESULTS: The DCE- parameters provided a good histologic match the tumor vascular characterizations. In the high pericyte coverage status, imatinib exhibited significant tumor growth inhibition, necrosis increase and pericyte coverage downregulation, and these changes were accompanied by increased vessel permeability, decreased microvessel density (MVD), increased tumor apoptosis and altered gene expression of apoptosis-related Bcl-2/bax pathway. Strategically, a 4-day imatinib effectively decreased pericyte coverage and HIF-1α level, and continuous treatment led to a less marked decrease in pericyte coverage and re-elevated HIF-1α level. Correlation analysis confirmed the feasibility of using mpMRI parameters to monitor imatinib treatment, with DCE-derived Ve and Ktrans being most correlated with pericyte coverage, Ve with vessel permeability, AUC with microvessel density (MVD), DWI-derived ADC with tumor apoptosis, and APT CEST-derived MTRasym at 1 µT with HIF-1α.
CONCLUSIONS: These results provided an optimized imatinib regimen to achieve decreasing pericyte coverage and HIF-1α level in the high pericyte-coverage CRC model, and offered an ultrahigh-field multiparametric MRI approach for monitoring pericyte coverage and dynamics response of the TME to treatment.

BACKGROUND: It has been proposed that anti-angiogenesis therapy could induce tumor \"vascular normalization\" and further enhance the efficacy of chemotherapy, radiotherapy, target therapy, and immunotherapy for nearly twenty years. However, the detailed molecular mechanism of this phenomenon is still obscure.
METHODS: Overexpression and knockout of CCL28 in human lung adenocarcinoma cell line A549 and murine lung adenocarcinoma cell line LLC, respectively, were utilized to establish mouse models. Single-cell sequencing was performed to analyze the proportion of different cell clusters and metabolic changes in the tumor microenvironment (TME). Immunofluorescence and multiplex immunohistochemistry were conducted in murine tumor tissues and clinical biopsy samples to assess the percentage of pericytes coverage. Primary pericytes were isolated from lung adenocarcinoma tumor tissues using magnetic-activated cell sorting (MACS). These pericytes were then treated with recombinant human CCL28 protein, followed by transwell migration assays and RNA sequencing analysis. Changes in the secretome and metabolome were examined, and verification of retinoic acid metabolism alterations in pericytes was conducted using quantitative real-time PCR, western blotting, and LC-MS technology. Chromatin immunoprecipitation followed by quantitative PCR (ChIP-qPCR) was employed to validate the transcriptional regulatory ability and affinity of RXRα to specific sites at the ANGPT1 promoter.
RESULTS: Our study showed that after undergoing anti-angiogenesis treatment, the tumor exhibited a state of ischemia and hypoxia, leading to an upregulation in the expression of CCL28 in hypoxic lung adenocarcinoma cells by the hypoxia-sensitive transcription factor CEBPB. Increased CCL28 could promote tumor vascular normalization through recruiting and metabolic reprogramming pericytes in the tumor microenvironment. Mechanistically, CCL28 modified the retinoic acid (RA) metabolism and increased ANGPT1 expression via RXRα in pericytes, thereby enhancing the stability of endothelial cells.
CONCLUSIONS: We reported the details of the molecular mechanisms of \"vascular normalization\" after anti-angiogenesis therapy for the first time. Our work might provide a prospective molecular marker for guiding the clinical arrangement of combination therapy between anti-angiogenesis treatment and other therapies.

Blood-brain barrier (BBB) damage significantly affects the prognosis of ischemic stroke patients. This project employed multi-omics analysis to identify key factors regulating BBB disruption during cerebral ischemia-reperfusion. An integrated analysis of three transcriptome sequencing datasets from mouse middle cerebral artery occlusion/reperfusion (MCAO/R) models identified eight downregulated genes in endothelial cells. Additionally, transcriptome analysis of BBB (cortex) and non-BBB (lung) endothelium of E13.5 mice revealed 2,102 upregulated genes potentially associated with BBB integrity. The eight downregulated genes were intersected with the 2,102 BBB-related genes and mapped using single-cell RNA sequencing data, revealing that solute carrier family 22 member 8 (Slc22a8) is specifically expressed in endothelial cells and pericytes and significantly decreases after MCAO/R. This finding was validated in the mouse MCAO/R model at both protein and mRNA levels in this study. External overexpression of Slc22a8 using a lentivirus carrying Tie2 improved Slc22a8 and tight junction protein levels and reduced BBB leakage after MCAO/R, accompanied by Wnt/β-catenin signaling activation. In conclusion, this study suggested that MCAO/R-induced downregulation of Slc22a8 expression may be a crucial mechanism underlying BBB disruption. Interventions that promote Slc22a8 expression or enhance its function hold promise for improving the prognosis of patients with cerebral ischemia.

Spinal cord injury (SCI) leads to fibrotic scar formation at the lesion site, yet the heterogeneity of fibrotic scar remains elusive. Here we show the heterogeneity in distribution, origin, and function of fibroblasts within fibrotic scars after SCI in mice and female monkeys. Utilizing lineage tracing and single-cell RNA sequencing (scRNA-seq), we found that perivascular fibroblasts (PFs), and meningeal fibroblasts (MFs), rather than pericytes/vascular smooth cells (vSMCs), primarily contribute to fibrotic scar in both transection and crush SCI. Crabp2 + /Emb+ fibroblasts (CE-F) derived from meninges primarily localize in the central region of fibrotic scars, demonstrating enhanced cholesterol synthesis and secretion of type I collagen and fibronectin. In contrast, perivascular/pial Lama1 + /Lama2+ fibroblasts (LA-F) are predominantly found at the periphery of the lesion, expressing laminin and type IV collagen and functionally involved in angiogenesis and lipid transport. These findings may provide a comprehensive understanding for remodeling heterogeneous fibrotic scars after SCI.

UNASSIGNED: Ischemic stroke (IS) is one of the leading causes of death and disability in the world, and alcohol consumption has been gaining attention as an independent risk factor for IS. Blood-brain barrier (BBB) dysfunction and neuroinflammation are the core of cerebral ischemia/reperfusion (I/R) injury, and pericytes play a crucial role in the structure and function. This study is to explore the effects of long-term alcohol consumption on IS and the potential mechanisms of pericytes.
UNASSIGNED: Rat models of long-term alcohol intake followed by transient middle cerebral artery occlusion stroke (EtOH+tMCAO) and cell models of oxygen-glucose deprivation/reoxygenation (OGD/R) with alcohol pre-treatment were constructed.
UNASSIGNED: Worsened infarct volume, neurological scores, and BBB disruption were observed in the EtOH+tMCAO group compared with the tMCAO group, and immunofluorescence staining showed increased pericytes NLPR3 inflammasome activation at the ischemic penumbra. In vitro, pericyte mortality and LDH release elevated pre-treated by alcohol after OGD/R, and amplified expression of NLRP3 inflammasome was detected by Western blotting and qPCR. Alcohol pre-treatment activated the TLR4/NF-κB pathway, and transfecting pericytes with TLR4-small interfering RNA (siRNA) to block TLR4 signaling markedly restrained NLRP3 inflammasome over-activation. Injecting TAK-242 in rats alleviated neurological impairment caused by alcohol.
UNASSIGNED: Long-term alcohol pre-treatment aggravated ischemic stroke-induced brain damage by activating NLRP3 inflammasome via TLR4/NF-κB signaling pathway in the pericytes.

UNASSIGNED: Disorders of the blood-brain barrier (BBB) arising from diabetes mellitus are closely related to diabetic encephalopathy. Previous research has suggested that neuron-glia antigen 2 (NG2)-glia plays a key role in maintaining the integrity of the BBB. However, the mechanism by which NG2-glia regulates the diabetic BBB remains unclear.
UNASSIGNED: Type 2 diabetes mellitus (T2DM) db/db mice and db/m mice were used. Evans-Blue BBB permeability tests and transmission electron microscopy techniques were applied. Tight junction proteins were assessed by immunofluorescence and transmission electron microscopy. NG2-glia number and signaling pathways were evaluated by immunofluorescence. Detection of matrix metalloproteinase-9 (MMP-9) in serum was performed using enzyme-linked immunosorbent assay (ELISA).
UNASSIGNED: In T2DM db/db mice, BBB permeability in the hippocampus significantly increased from 16 weeks of age, and the structure of tight junction proteins changed. The number of NG2-glia in the hippocampus of db/db mice increased around microvessels from 12 weeks of age. Concurrently, the expression of MMP-9 increased in the hippocampus with no change in serum. Sixteen- week-old db/db mice showed activation of the Wnt/β-catenin signaling in hippocampal NG2-glia. Treatment with XAV-939 improved structural and functional changes in the hippocampal BBB and reduced MMP-9 secretion by hippocampal NG2-glia in db/db mice. It was also found that the upregulation of β-catenin protein in NG2-glia in the hippocampus of 16-week-old db/db mice was significantly alleviated by treatment with XAV-939.
UNASSIGNED: The results indicate that NG2-glia can lead to structural and functional disruption of the diabetic BBB by activating Wnt/β-catenin signaling, upregulating MMP-9, and degrading tight junction proteins.

Objective: To investigate the role and underlying mechanisms of methyltransferase (Mettl) 3 in the process of angiotensin Ⅱ (Ang Ⅱ)-induced pericyte-to-myofibroblast transdifferentiation and renal fibrosis. Methods: C57BL/6J mice were used, in cell experiments, mouse renal pericytes were isolated and cultured using magnetic bead sorting. These pericytes were then induced to transdifferentiate into myofibroblasts with 1×106 mmol/L Ang Ⅱ, which was the Ang Ⅱ group, while pericytes cultured in normal conditions served as the control group. Successful transdifferentiation was verified by immunofluorescence staining, Western blotting, and real-time reverse transcription PCR (RT-qPCR) for α-smooth muscle actin (α-SMA). The levels of m6A modifications and related enzymes (Mettl3, Mettl14), Wilms tumor 1-associated protein (WTAP), fat mass and obesity protein (FTO), ALKBH5, YTHDF1, YTHDF2, YTHDC1, YTHDC2, YTHDC3 were assessed by Dot blot, RT-qPCR and Western blot. Mettl3 expression was inhibited in cells using lentivirus-mediated Mettl3-shRNA transfection, creating sh-Mettl3 and Ang Ⅱ+sh-Mettl3 groups, while lentivirus empty vector transfection served as the negative control (Ang Ⅱ+sh-NC group). The impact of Ang Ⅱ on pericyte transdifferentiation was observed, and the expression of downstream phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway proteins, including PI3K, AKT, phosphorylated AKT at serine 473 (p-AKT (S473)), and phosphorylated AKT at threonine 308 (p-AKT (T308)), were examined. PI3K gene transcription was inhibited by co-culturing cells with actinomycin D, and the half-life of PI3K mRNA was calculated by measuring residual PI3K mRNA expression over different co-culture time. The reversibility of Mettl3 inhibition on Ang Ⅱ-induced pericyte-to-myofibroblast transdifferentiation was assessed by adding the AKT activator SC79 to the Ang Ⅱ+sh-Mettl3 group. In animal experiments, mice were divided into these groups: sham group (administered 0.9% sterile saline), Ang Ⅱ group (infused with Ang Ⅱ solution), sh-Mettl3 group (injected with Mettl3 shRNA lentivirus solution), Ang Ⅱ+sh-Mettl3 group (infused with Ang Ⅱ solution and injected with Mettl3 shRNA lentivirus solution), and Ang Ⅱ+sh-Mettl3+SC79 group (administered Ang Ⅱ solution and Mettl3 shRNA lentivirus, with an additional injection of SC79). Each group consisted of six subject mice. Blood pressure was measured using the tail-cuff method before and after surgery, and serum creatinine, urea, and urinary albumin levels were determined 4 weeks post-surgery. Kidney tissues were collected at 28 days and stained using hematoxylin-eosin (HE) and Masson\'s trichrome to assess the extent of renal fibrosis. Results: Primary renal pericytes were successfully obtained by magnetic bead sorting, and intervened with 1×106 mmol/L Ang Ⅱ for 48 hours to induce pericyte-to-myofibroblast transdifferentiation. Dot blot results indicated higher m6A modification levels in the Ang Ⅱ group compared to the control group (P<0.05). RT-qPCR and Western blot results showed upregulation of Mettl3 mRNA and protein levels in the Ang Ⅱ group compared to the control group (both P<0.05). In the Ang Ⅱ+sh-Mettl3 group, Mettl3 protein expression was lower than that in the Ang Ⅱ group, with reduced expression levels of α-SMA, vimentin, desmin, fibroblast agonist protein (FAPa) and type Ⅰ collagen (all P<0.05). Compared to the control group, PI3K mRNA expression level was elevated in the Ang Ⅱ group, along with increased p-AKT (S473) and p-AKT (T308) expressions. In the Ang Ⅱ+sh-Mettl3 group, PI3K mRNA expression and p-AKT (S473) and p-AKT (T308) levels were decreased (all P<0.05). The half-life of PI3K mRNA was shorter in the Ang Ⅱ+sh-Mettl3 group than that in the Ang Ⅱ+sh-NC group (2.34 h vs. 3.42 h). The ameliorative effect of Mettl3 inhibition on Ang Ⅱ-induced pericyte-to-myofibroblast transdifferentiation was reversible by SC79. Animal experiments showed higher blood pressure, serum creatinine, urea, and 24-hour urinary protein levels, and a larger fibrosis area in the Ang Ⅱ group compared to the sham group (all P<0.05). The fibrosis area was smaller in the Ang Ⅱ+sh-Mettl3 group than that in the Ang Ⅱ group (P<0.05), but increased again upon addition of SC79. Conclusion: Mettl3-mediated RNA m6A epigenetic regulation is involved in Ang Ⅱ-induced pericyte-to-myofibroblast transdifferentiation and renal fibrosis, potentially by affecting PI3K stability and regulating the PI3K/AKT signaling pathway.
目的： 探讨甲基转移酶3（Mettl3）在血管紧张素Ⅱ（Ang Ⅱ）诱导周细胞向肌成纤维细胞转分化及肾脏纤维化过程中的作用及相关机制。 方法： 使用C57BL/6J小鼠，（1）细胞实验中，采用磁珠分选法培养纯化小鼠肾脏周细胞，并予以1×106 mmol/L的Ang Ⅱ诱导周细胞-肌成纤维细胞转分化，为Ang Ⅱ组；正常培养的周细胞为对照组。采用免疫荧光染色、蛋白质印迹（Western blot）及实时反转录PCR（RT-qPCR）检测α平滑肌肌动蛋白（α-SMA）以验证转分化成功。采用斑点印迹、RT-qPCR、Western blot检测N6-甲基腺苷（m6A）修饰水平及相关酶［Mettl3、Mettl14、Wilms肿瘤蛋白1相关蛋白（WTAP）、肥胖相关蛋白（FTO）、ALKB同源蛋白5（ALKBH5）、YTH结构域家族蛋白（YTHDF）1、YTHDF2、YTHDC1、YTHDC2、YTHDC3］的表达水平。采用慢病毒转染Mettl3 shRNA的方法抑制细胞中的Mettl3表达，为sh-Mettl3组、Ang Ⅱ+sh-Mettl3组；以转染慢病毒空载体作为阴性对照，为Ang Ⅱ+sh-NC组，观察Ang Ⅱ对周细胞转分化的影响，并检测下游磷脂酰肌醇3激酶（PI3K）/蛋白激酶B（AKT）信号通路蛋白的表达，包括PI3K、AKT（丝氨酸磷酸化位点473）［p-AKT（S473）］、AKT（苏氨酸磷酸化位点308）［p-AKT（T308）］等。加入放线菌素D与各组周细胞共培养以抑制PI3K基因的转录，通过检测不同共培养时间残余PI3K mRNA表达量以计算PI3K mRNA半衰期。在Ang Ⅱ+sh-Mettl3组周细胞中加入AKT激动剂SC79，观察是否可逆转Mettl3抑制对Ang Ⅱ诱导周细胞-肌成纤维细胞转分化的作用。（2）动物实验中，分为假手术组（仅给予0.9%无菌生理盐水）、Ang Ⅱ组（泵入Ang Ⅱ溶液）、sh-Mettl3组（注射Mettl3 shRNA慢病毒溶液）、Ang Ⅱ+sh-Mettl3组（泵入Ang Ⅱ溶液+注射Mettl3 shRNA慢病毒溶液）、Ang Ⅱ+sh-Mettl3+SC79组（Ang Ⅱ+sh-Mettl3组处理基础上注射SC79），每组6只。手术前后采用尾夹法测定血压，术后4周测定血清肌酐、尿素含量及尿液白蛋白含量。28 d后取肾脏组织，采用苏木精-伊红（HE）及Masson三色法对组织切片进行染色，检测肾脏纤维化程度。 结果： （1）磁珠分选法可获得原代肾脏周细胞，以1×106 mmol/L的Ang Ⅱ处理周细胞48 h可成功诱导其向肌成纤维细胞转分化。斑点印迹结果显示，Ang Ⅱ组总RNA的m6A修饰水平高于对照组（P<0.05），RT-qPCR及Western blot结果显示，与对照组相比，Ang Ⅱ组中Mettl3 mRNA及蛋白表达水平上调（P均<0.05）。Ang Ⅱ+sh-Mettl3组细胞中的Mettl3蛋白表达水平低于Ang Ⅱ组，α-SMA、波形蛋白、肌间线蛋白、成纤维细胞激活蛋白a（FAPa）以及Ⅰ型胶原蛋白的表达水平亦低于Ang Ⅱ组（P均<0.05）。与对照组相比，Ang Ⅱ组的PI3K mRNA表达水平上调，且p-AKT（S473）和p-AKT（T308）蛋白高表达；Ang Ⅱ+sh-Mettl3组的PI3K mRNA表达水平低于Ang Ⅱ组，p-AKT（S473）和p-AKT（T308）蛋白表达下调（P均<0.05）。Ang Ⅱ+sh-Mettl3组的半衰期短于Ang Ⅱ+sh-NC组（2.34 h比3.42 h）。而Mettl3抑制对Ang Ⅱ诱导周细胞-肌成纤维细胞转分化的改善作用可被SC79逆转。（2）动物实验结果显示，与假手术组比较，Ang Ⅱ组小鼠的血压更高，血清肌酐、尿素及24 h尿蛋白测量值更高，纤维化面积更大（P均<0.05）；而Ang Ⅱ+sh-Mettle3组的纤维化面积小于Ang Ⅱ组（P<0.05），但在加入SC79后肾脏纤维化又加重。 结论： Mettl3介导的RNA m6A表观遗传调控参与Ang Ⅱ诱导的肾脏周细胞-肌成纤维细胞转分化及肾脏纤维化，Mettl3可能通过影响PI3K的稳定性，进而影响PI3K/AKT信号通路发挥调控作用。.