Dynamic pressure surface deformation measurement based on a chromatic confocal sensor: erratum.

This erratum corrects errors in Fig. 4 of the original paper, Appl. Opt.62, 1467 (2023)APOPAI0003-693510.1364/AO.482808.

Cilia-related diseases.

More and more attention is paid to diseases such as internal transfer and brain malformation which are caused by the abnormal morphogenesis of cilia. These cilia-related diseases are divided into two categories: ciliopathy resulting from defects of primary cilia and primary ciliary dyskinesia (PCD) caused by functional dysregulation of motile cilia. Cilia are widely distributed, and their related diseases can cover many human organs and tissues. Recent studies prove that primary cilia play a key role in maintaining homeostasis in the cardiovascular system. However, molecular mechanisms of cilia-related diseases remain elusive. Here, we reviewed recent research progresses on characteristics, molecular mechanisms and treatment methods of ciliopathy and PCD. Our review is beneficial to the further research on the pathogenesis and treatment strategies of cilia-related diseases.

ATIC-Associated De Novo Purine Synthesis Is Critically Involved in Proliferative Arterial Disease.

BACKGROUND: Proliferation of vascular smooth muscle cells (VSMCs) is a hallmark of arterial diseases, especially in arterial restenosis after angioplasty or stent placement. VSMCs reprogram their metabolism to meet the increased requirements of lipids, proteins, and nucleotides for their proliferation. De novo purine synthesis is one of critical pathways for nucleotide synthesis. However, its role in proliferation of VSMCs in these arterial diseases has not been defined. METHODS: De novo purine synthesis in proliferative VSMCs was evaluated by liquid chromatography-tandem mass spectrometry. The expression of ATIC (5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase/inosine monophosphate cyclohydrolase), the critical bifunctional enzyme in the last 2 steps of the de novo purine synthesis pathway, was assessed in VSMCs of proliferative arterial neointima. Global and VSMC-specific knockout of Atic mice were generated and used for examining the role of ATIC-associated purine metabolism in the formation of arterial neointima and atherosclerotic lesions. RESULTS: In this study, we found that de novo purine synthesis was increased in proliferative VSMCs. Upregulated purine synthesis genes, including ATIC, were observed in the neointima of the injured vessels and atherosclerotic lesions both in mice and humans. Global or specific knockout of Atic in VSMCs inhibited cell proliferation, attenuating the arterial neointima in models of mouse atherosclerosis and arterial restenosis. CONCLUSIONS: These results reveal that de novo purine synthesis plays an important role in VSMC proliferation in arterial disease. These findings suggest that targeting ATIC is a promising therapeutic approach to combat arterial diseases.

Dynamic pressure surface deformation measurement based on a chromatic confocal sensor.

To enable the real-time measurement of pressure deformations in sealed cavities, a high-precision method of detecting the deformation of a material surface is proposed. By combining a chromatic confocal displacement sensor with a pressure sensor, we can acquire dynamic online strain measurements that consider the effects of the deformed material and internal environmental conditions. A 90m m×90m m static mechanical cylindrical cavity is simulated using finite element software. The interior of the cylindrical cavity is continuously pressurized at up to 400 kPa with a material deformation of 300 µm. We experimentally obtain the spectral peak wavelengths corresponding to the surface deformation experiment, record the spectral data at 20 kPa intervals, and use the Voigt fitting algorithm to reduce sensor errors. The results show that the experimental results differ from the simulated results by 1.43 µm, with a relative error of 0.083% after sequential pressurization and depressurization using a pressure calibrator, and the uncertainty error of pressure deformation measurement is 1.495 µm. Thus, the proposed method is robust against external disturbances and is suitable for micrometer-level surface deformation monitoring, which has numerous applications in the high-precision inspection industry.

Deoxynivalenol induces caspase-3/GSDME-dependent pyroptosis and inflammation in mouse liver and HepaRG cells.

Deoxynivalenol (DON), a frequent food and feed contaminant, poses a severe threat to human and livestock health. Some studies have demonstrated that DON could induce liver damage and cell death. However, novel cell death styles and detailed mechanisms to explain DON-induced liver inflammatory injury are still lacking. Here, we found both chronic and subacute oral administration of DON (3 mg/kg for 4 weeks and 4 mg/kg for 8 days) induced mouse liver inflammatory injury and activated caspase-3, PARP and gasdermin E (GSDME), which were inhibited by caspase-3 inhibitor Z-DEVD and Ac-DEVD. In vitro, HepaRG cells showed typical pyroptotic characteristics after 32 and 64 µM DON exposure for 24 h, including balloon-like bubbling emerging, release of lactate dehydrogenase (LDH), secretion of IL-1ß and IL-6 and activation of caspase-3 and GSDME. Furthermore, knocking down GSDME and inhibiting caspases activity by Z-VAD and Z-DEVD dramatically blocked DON-induced pyroptotic characteristics, while over-expressed GSDME prompted that. These data demonstrate that caspase-3/GSDME pathway plays a key factor in DON-induced pyroptosis and inflammation in liver. Interestingly, knocking down GSDME could inhibit DON-induced pyroptosis but prompt DON-induced apoptosis, while opposite results were obtained when over-expressed GSDME, indicating the critical role of GSDME in DON-induced crosstalk between apoptosis and pyroptosis. Taken together, our data determine DON-induced caspase-3/GSDME-dependent pyroptosis in liver and its role in DON-induced liver inflammatory injury, which provide a novel mechanistic view into DON-induced hepatotoxicity and may offer a new target to reduce latent harm of DON to both humans and animals.

T-2 Toxin Induces Oxidative Stress at Low Doses via Atf3ΔZip2a/2b-Mediated Ubiquitination and Degradation of Nrf2.

T-2 toxin is mainly produced by Fusarium species, which is an extremely toxic mycotoxin to humans and animals. It is well known that T-2 toxin induces oxidative stress, but the molecular mechanism is still unknown. In this study, we found that T-2 toxin significantly promoted reactive oxygen species (ROS) accumulation in MCF-7 cells at low doses which maintains cell viability at least 80%. Further analysis showed that T-2 toxin downregulated the expression of the master regulator of antioxidant defense gene, nuclear factor erythroid 2-related factor (Nrf2), and its targeted antioxidant genes. Overexpression of Nrf2 or its target gene heme oxygenase 1 (HO1) significantly blocked the ROS accumulation in MCF-7 cells under T-2 toxin treatment. Moreover, we found that T-2 toxin downregulated the antioxidant genes via inducing the expression of ATF3ΔZip2a/2b. Importantly, overexpression of ATF3ΔZip2a/2b promoted the ubiquitination and degradation of Nrf2. Altogether, our results demonstrated that T-2 toxin-induced ROS accumulation via ATF3ΔZip2a/2b mediated ubiquitination and degradation of Nrf2, which provided a new insight into the mechanism of T-2 toxin-induced oxidative stress.

Ablation of endothelial Pfkfb3 protects mice from acute lung injury in LPS-induced endotoxemia.

Acute lung injury (ALI) is one of the leading causes of death in sepsis. Endothelial inflammation and dysfunction play a prominent role in development of ALI. Glycolysis is the predominant bioenergetic pathway for endothelial cells (ECs). However, the role of EC glycolysis in ALI of sepsis remains unclear. Here we show that both the expression and activity of PFKFB3, a key glycolytic activator, were markedly increased in lipopolysaccharide (LPS)-treated human pulmonary arterial ECs (HPAECs) in vitro and in lung ECs of mice challenged with LPS in vivo. PFKFB3 knockdown significantly reduced LPS-enhanced glycolysis in HPAECs. Compared with LPS-challenged wild-type mice, endothelial-specific Pfkfb3 knockout (Pfkfb3ΔVEC) mice exhibited reduced endothelium permeability, lower pulmonary edema, and higher survival rate. This was accompanied by decreased expression of intracellular adhesion molecule-1 (Icam-1) and vascular cell adhesion molecule 1 (Vcam-1), as well as decreased neutrophil and macrophage infiltration to the lung. Consistently, PFKFB3 silencing or PFKFB3 inhibition in HPAECs and human pulmonary microvascular ECs (HPMVECs) significantly downregulated LPS-induced expression of ICAM-1 and VCAM-1, and monocyte adhesion to human pulmonary ECs. In contrast, adenovirus-mediated PFKFB3 overexpression upregulated ICAM-1 and VCAM-1 expression in HPAECs. Mechanistically, PFKFB3 silencing suppressed LPS-induced nuclear translocation of nuclear factor κB (NF-κB)-p65, and NF-κB inhibitors abrogated PFKFB3-induced expression of ICAM-1 and VCAM-1. Finally, administration of the PFKFB3 inhibitor 3PO also reduced the inflammatory response of vascular endothelium and protected mice from LPS-induced ALI. Overall, these findings suggest that targeting PFKFB3-mediated EC glycolysis is an efficient therapeutic strategy for ALI in sepsis.

Super enhancers at the miR-146a and miR-155 genes contribute to self-regulation of inflammation.

Inflammatory response is essential to host defense and repair, and requires tight regulation as excessive and constant inflammatory response is deleterious. We recently identified that one of the general but key mechanisms for inflammatory gene transcription regulation is controlled by the formation of super enhancers mediated by NF-κB, and bromodomain and extraterminal (BET) proteins. Given that microRNA transcription shares a similar mechanism to mRNA, we assume that the inflammatory microRNAs transcription could be NF-κB and BET bromodomain dependent. In the present study, we confirmed that inflammatory stimuli changed human umbilical vein endothelial cells (HUVEC) microRNA profile. Among these microRNAs, miR-146a and miR-155, two well-established inflammatory microRNAs, are both downregulated at transcriptional level by NF-κB and BET bromodomain inhibition. To pursue this mechanism, we analyzed the ChIP-seq data and found that NF-κB, BRD4 and RNA POL II were rapidly distributed at the upstream regions of miR-146a and miR-155, and more importantly mediated the formation of the super enhancers that drive miR-146a and miR-155 transcription. These microRNAs transcription driven by super enhancers in turn downregulate both in vitro and in vivo canonical inflammatory genes expression through targeting inflammatory mediators. This novel finding demonstrated how the host self-regulates inflammatory genes expression at both transcriptional and post-transcriptional level to ensure the appropriate level of the host inflammatory response.

BET bromodomain is a novel regulator of TAZ and its activity.

Transcriptional coactivator with PDZ-binding motif (TAZ) is a key transcriptional mediator of Hippo signaling that has been recently reported to mediate Wnt-activated transcription and serve as a component to suppress canonical Wnt/ß-catenin activity. The Bromodomain and Extra-terminal domain (BET) family of proteins can recognize the acetylated lysine chain on histones and plays a critical role in transcriptional regulation. However, the mechanisms underlying transcriptional repression by the BET bromodomain are poorly understood. Here, we found that BET bromodomain inhibition upregulated TAZ protein and its transcriptional output, independent of its well-established role as a mediator of Hippo and Wnt signaling. Additionally, JQ1, a synthetic BET inhibitor, suppressed Wnt/ß-catenin activity by upregulating TAZ. Although JQ1 upregulated TAZ, which is known to promote cell proliferation, it drastically suppressed the growth of colon cancer cells by inducing cell cycle arrest. Collectively, our study identified an unexpected transcriptional repression function of the BET bromodomain and a novel mechanism for TAZ upregulation.

Monitoring Avian Influenza Viruses from Chicken Carcasses Sold at Markets, China, 2016.

During 2016 in Guangzhou, China, we detected infectious avian influenza viruses (AIVs) in 39.8% of samples from chicken carcasses slaughtered at live poultry markets but none from carcasses supplied to supermarkets by facilities bypassing live poultry markets. Promoting supply chains with high biosecurity may reduce the risk for zoonotic AIV transmission.

[Comparison of differentiated endothelial cells from the embryonic stem cells with human umbilical vein endothelial cells].

OBJECTIVE: To compare the differentiated endothelial cells from the embryonic stem cells in vitro with human umbilical vein endothelial cells (HUVECs).
 Methods: Induction of the stem cells HUES9 to endothelial cells follows 2 steps. Stem cells were treated with CHIR99021 (10 µmol/L) and bone morphogenetic protein 4 (25 ng/mL) for 3 days to keep mesoderm state, then subsequent exposure them to VEGF165 (200 ng/mL) and Forskolin (2 µmol/L) to differentiate into endothelial cells. The morphology of differentiated endothelial cells were compared with HUVECs. The surface marker CD144 on differentiated cells and HUVECs were detected. The capabilities of two types of endothelial cells in migration and angiogenesis were examined.
 Results: The differentiated endothelial cells show the same morphology with HUVECs. After 6 days of differentiation, the efficiency reached 73.4%. The positive percentage of CD144 for the differentiated endothelial cells and HUVECs was 86.6% and 94.4%, respectively. Both of them show capabilities of migration and angiogenesis, especially when they were treated with SB431542 to inhibit TGF-ß signal pathway.
 Conclusion: The method for induction of stem cells to endothelial cells is productivity and it can be used for further study.

[Y-27632 reduces the MMP2 and MMP9 expression in endothelial cell via inhibition of ROCK signal pathway].

OBJECTIVE: To explore the effect of ROCK inhibitor Y-27632 on the matrix metalloproteinase 2 and 9 (MMP2 and MMP9) gene expression and activity in tumor necrosis factor α (TNF-α)-treated human umbilical vein endothelial cell (HUVEC).
 METHODS: HHUVEC was divided into 3 groups, a control group, a TNF-α group, and a TNF-α plus Y-27632 group. The expressions of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), MMP2 and MMP9 were examined by real-time PCR. The MMP2/9 activity was measured by gelatin zymography.
 RESULTS: Compared to the control group, the mRNA expressions of ICAM-1, VCAM-1, MMP2 and MMP9 were increased TNF-α-treated cells, which were suppressed by ROCK inhibitor (P<0.01). The MMP2/9 activity was elevated in TNF-α-treated cells, which was reversed by ROCK inhibitor (P<0.05).
 CONCLUSION: ROCK inhibitor can suppress TNF-α-induced inflammation in endothelial cells through down-regulation of MMP2/9.

Impact of stent retriever size on clinical outcomes in the RECO registry.

Objective: In the RECO study, we investigated the impact of the operator's choice of stent retriever size on patients with internal carotid artery (ICA) occlusion. Methods: Data from the RECO Registry, a prospective multicentre study, were utilized. Patients who underwent mechanical thrombectomy (MT) were divided according to the size of the stent into the RECO 4 × 20 group, the RECO 5 × 30 group and the RECO 6 × 30 group. The outcome measures assessed in the study were the 3-month modified Rankin Scale (mRS) score, occurrence of any intracranial haemorrhage (aICH), workflow timing, recanalization success rate, number of attempts, and all-cause mortality within a 3-month period. Results: Analysis was conducted on a total of 89 patients with ICA occlusion. RECO 4 × 20, 5 × 30, and 6 × 30 stent retrievers were used in 19 (21.3%), 52 (58.4%), and 18 (20.2%) patients, respectively. The demographic and baseline characteristics showed considerable similarity across the three groups. The puncture-to-recanalization time of the RECO 6 × 30 group [56.5 min (IQR, 41.5-80.8)] was significantly shorter than that of the RECO 4 × 20 group [110 min (IQR, 47-135)]. In 10 out of 18 patients (55.6%), the RECO 6 × 30 stent retriever achieved reperfusion (modified Thrombolysis in Cerebral Infarction [mTICI] score 2b-3) after the initial attempt, surpassing the rates of 31.6% in the RECO 4 × 20 group and 32.7% in the RECO 5 × 30 group. In the RECO 4 × 20 group, the median number of passes was 2 (IQR, 1-3); in the RECO 5 × 30 group, it was 2 (IQR, 1-3); and in the RECO 6 × 30 groups, it was 1 (IQR, 1-2.5). There were no statistically significant differences observed among the three groups concerning aICH or good outcomes (mRS score 0-2). Conclusion: Our study demonstrated the practical implications of stent-retriever size selection in the context of the MT for ICA occlusion. The routine use of a RECO 6 × 30 stent retriever holds the potential for early revascularization in clinical practice. The significant reduction in the puncture-to-reperfusion time and the greater first-pass effect associated with this stent size underscore its efficiency in treating ICA occlusion.

Single-cell transcriptome analyses reveal microglia types associated with proliferative retinopathy.

Pathological angiogenesis is a major cause of irreversible blindness in individuals of all age groups with proliferative retinopathy (PR). Mononuclear phagocytes (MPs) within neovascular areas contribute to aberrant retinal angiogenesis. Due to their cellular heterogeneity, defining the roles of MP subsets in PR onset and progression has been challenging. Here, we aimed to investigate the heterogeneity of microglia associated with neovascularization and to characterize the transcriptional profiles and metabolic pathways of proangiogenic microglia in a mouse model of oxygen-induced PR (OIR). Using transcriptional single-cell sorting, we comprehensively mapped all microglia populations in retinas of room air (RA) and OIR mice. We have unveiled several unique types of PR-associated microglia (PRAM) and identified markers, signaling pathways, and regulons associated with these cells. Among these microglia subpopulations, we found a highly proliferative microglia subset with high self-renewal capacity and a hypermetabolic microglia subset that expresses high levels of activating microglia markers, glycolytic enzymes, and proangiogenic Igf1. IHC staining shows that these PRAM were spatially located within or around neovascular tufts. These unique types of microglia have the potential to promote retinal angiogenesis, which may have important implications for future treatment of PR and other pathological ocular angiogenesis-related diseases.

Endothelial AMPKα1/PRKAA1 exacerbates inflammation in HFD-fed mice.

BACKGROUND AND PURPOSE: Excess nutrient-induced endothelial cell inflammation is a hallmark of high fat diet (HFD)-induced metabolic syndrome. Pharmacological activation of the protein kinase AMP-activated α1 (PRKAA1) also known as AMPKα1, shows its beneficial effects in many studies of cardiometabolic disorders. However, AMPKα1, as a major cellular sensor of energy and nutrients in endothelial cells, has not been studied for its physiological role in excess nutrient-induced endothelial cell (EC) inflammation. EXPERIMENTAL APPROACH: Wild-type and EC-specific Prkaa1 knockout mice were fed with an HFD. Body weight, fat mass composition, glucose, and lipid levels were monitored regularly. Insulin sensitivity was analysed systemically and in major metabolic organs/tissues. Inflammation status in metabolic organs/tissues were examined with quantitative RT-PCR and flow cytometry. Additionally, metabolic status, inflammation severity, and signalling in cultured ECs were assayed with multiple approaches at the molecular level. KEY RESULTS: EC Prkaa1 deficiency unexpectedly alleviated HFD-induced metabolic syndromes including decreased body weight and fat mass, enhanced glucose clearance and insulin sensitivity, and relieved adipose inflammation and hepatic steatosis. Mechanistically, PRKAA1 knockdown in cultured ECs reduced endothelial glycolysis and fatty acid oxidation, decreased levels of acetyl-CoA and suppressed transcription of inflammatory molecules mediated by ATP citrate lyase and histone acetyltransferase p300. CONCLUSIONS AND IMPLICATIONS: This unexpected pro-inflammatory effect of endothelial AMPKα1/PRKAA1 in a metabolic context provides additional insight in AMPKα1/PRKAA1 activities. An in-depth study and thoughtful consideration should be applied when AMPKα1/PRKAA1 is used as a therapeutic target in the treatment of metabolic syndrome.

Suppression of myeloid PFKFB3-driven glycolysis protects mice from choroidal neovascularization.

BACKGROUND AND PURPOSE: Pathological angiogenesis is a major cause of irreversible blindness in individuals with neovascular age-related macular degeneration (nAMD). Macrophages and microglia (MΦ) contribute to aberrant ocular angiogenesis. However, the role of glucose metabolism of MΦ in nAMD is still undefined. Here, we have investigated the involvement of glycolysis, driven by the kinase/phosphatase PFKFB3, in the development of choroidal neovascularization (CNV). EXPERIMENTAL APPROACH: CNV was induced in mice with laser photocoagulation. Choroid/retinal pigment epithelium (RPE) complexes and MΦ were isolated for analysis by qRT-PCR, western blot, flow cytometry, immunostaining, metabolic measurements and angiogenesis assays. KEY RESULTS: MΦ accumulated within the CNV of murine nAMD models and expressed high levels of glycolysis-related enzymes and M1/M2 polarization markers. This phenotype of hyper-glycolytic and activated MΦ was replicated in bone marrow-derived macrophages stimulated by necrotic RPE in vitro. Myeloid cell-specific knockout of PFKFB3, a key glycolytic activator, attenuated pathological neovascularization in laser-induced CNV, which was associated with decreased expression of MΦ polarization markers and pro-angiogenic factors, along with decreased sprouting of vessels in choroid/RPE complexes. Mechanistically, necrotic RPE increased PFKFB3-driven glycolysis in macrophages, leading to activation of HIF-1α/HIF-2α and NF-κB, and subsequent induction of M1/M2 markers and pro-angiogenic cytokines, finally promoting macrophage reprogramming towards an angiogenic phenotype to facilitate development of CNV. The PFKFB3 inhibitor AZ67 also inhibited activation of HIF-1α/HIF-2α and NF-κB signalling and almost completely prevented laser-induced CNV in mice. CONCLUSIONS AND IMPLICATIONS: Modulation of PFKFB3-mediated macrophage glycolysis and activation is a promising strategy for the treatment of nAMD.

Identification and Validation of a Ferroptosis-Related Signature for Predicting Prognosis and Immune Microenvironment in Papillary Renal Cell Carcinoma.

Objective: We aimed to explore the prognostic patterns of ferroptosis-related genes in papillary renal cell carcinoma (PRCC) and investigate the relationship between ferroptosis-related genes and PRCC tumor immune microenvironment. Methods: We obtained the mRNA expression and corresponding clinical data of PRCC from the public tumor cancer genome atlas database (TCGA). The PRCC patients were randomly divided into two cohort, training cohort and verification cohort, respectively. Univariate Cox regression, LASSO Cox regression, multivariate Cox regression analysis were utilized to construct ferroptosis signature for PRCC patients. And then, risk prognostic model was established and verified. The correlation of ferroptosis-related signature with survival and immune microenvironment was systematically analyzed. Results: A 4-genes ferroptosis signature (CDKN1A, MIOX, PSAT1, and RRM2) was constructed. Multivariate Cox regression assay indicates that the risk score of ferroptosis signature was an independent prognostic indicator (HR=1.391, p<0.001). The survival curve shows that the high-risk group has a poorer prognosis than the low-risk group (p<0.001). The risk prognostic model was established based on prognostic factors of clinical-stage, hemoglobin, and risk score. The time-dependent receiver operating characteristic curve (ROC) analysis proves the predictive capacity of the ferroptosis signature, the 3 years area under the curve (AUC) is 0.890, and the 5 years AUC is 0.733. Further analysis suggested that cell cycle, pentose phosphate pathway, P53 signaling pathway were significantly enriched in the high-risk group. The significantly different fractions of dendritic cells resting, macrophage cells, and T cells follicular helper were observed in risk groups. Conclusion: This study implicates a ferroptosis signature which has a good predict capacity of the prognosis in PRCC patients. Ferroptosis-related genes may have a key role in the process of anti-tumor and serve as therapeutic targets for PRCC.

Distinct gut microbiota and health outcomes in asymptomatic infection, viral nucleic acid test re-positive, and convalescent COVID-19 cases.

Gut microbiota composition is suggested to associate with coronavirus disease 2019 (COVID-19) severity, but the impact of gut microbiota on health outcomes is largely unclear. We recruited 81 individuals from Wuhan, China, including 13 asymptomatic infection cases (Group A), 24 COVID-19 convalescents with adverse outcomes (Group C), 31 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) re-positive cases (Group D), and 13 non-COVID-19 healthy controls (Group H). The microbial features of Groups A and D were similar and exhibited higher gut microbial diversity and more abundant short-chain fatty acid (SCFA)-producing species than Group C. Group C was enriched with opportunistic pathogens and virulence factors related to adhesion and toxin production. The abundance of SCFA-producing species was negatively correlated, while Escherichia coli was positively correlated with adverse outcomes. All three groups (A, C, and D) were enriched with the mucus-degrading species Akkermansia muciniphila, but decreased with Bacteroides-encoded carbohydrate-active enzymes. The pathways of vitamin B6 metabolic and folate biosynthesis were decreased, while selenocompound metabolism was increased in the three groups. Specifically, the secondary bile acid (BA) metabolic pathway was enriched in Group A. Antibiotic resistance genes were common among the three groups. Conclusively, the gut microbiota was related to the health outcomes of COVID-19. Dietary supplementations (SCFAs, BA, selenium, folate, vitamin B6) may be beneficial to COVID-19 patients.

Disruption of endothelial Pfkfb3 ameliorates diet-induced murine insulin resistance.

Overnutrition-induced endothelial inflammation plays a crucial role in high-fat diet (HFD)-induced insulin resistance in animals. Endothelial glycolysis plays a critical role in endothelial inflammation and proliferation, but its role in diet-induced endothelial inflammation and subsequent insulin resistance has not been elucidated. PFKFB3 is a critical glycolytic regulator, and its increased expression has been observed in adipose vascular endothelium of C57BL/6J mice fed with HFD in vivo, and in palmitate (PA)-treated primary human adipose microvascular endothelial cells (HAMECs) in vitro. We generated mice with Pfkfb3 deficiency selective for endothelial cells to examine the effect of endothelial Pfkfb3 in endothelial inflammation in metabolic organs and in the development of HFD-induced insulin resistance. EC Pfkfb3-deficientmice exhibited mitigated HFD-induced insulin resistance, including decreased body weight and fat mass, improved glucose clearance and insulin sensitivity, and alleviated adiposity and hepatic steatosis. Mechanistically, cultured PFKFB3 knockdown HAMECs showed decreased NF-κB activation induced by PA, and consequent suppressed adhesion molecule expression and monocyte adhesion. Taken together, these results demonstrate that increased endothelial PFKFB3 expression promotes diet-induced inflammatory responses and subsequent insulin resistance, suggesting that endothelial metabolic alteration plays an important role in the development of insulin resistance.

Deficiency of Myeloid Pfkfb3 Protects Mice From Lung Edema and Cardiac Dysfunction in LPS-Induced Endotoxemia.

Sepsis, a pathology resulting from excessive inflammatory response that leads to multiple organ failure, is a major cause of mortality in intensive care units. Macrophages play an important role in the pathophysiology of sepsis. Accumulating evidence has suggested an upregulated rate of aerobic glycolysis as a key common feature of activated proinflammatory macrophages. Here, we identified a crucial role of myeloid 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (Pfkfb3), a glycolytic activator in lipopolysaccharide (LPS)-induced endotoxemia in mice. Pfkfb3 expression is substantially increased in bone marrow derived macrophages (BMDMs) treated with LPS in vitro and in lung macrophages of mice challenged with LPS in vivo. Myeloid-specific knockout of Pfkfb3 in mice protects against LPS-induced lung edema, cardiac dysfunction and hypotension, which were associated with decreased expression of interleukin 1 beta (Il1b), interleukin 6 (Il6) and nitric oxide synthase 2 (Nos2), as well as reduced infiltration of neutrophils and macrophages in lung tissue. Pfkfb3 ablation in cultured macrophages attenuated LPS-induced glycolytic flux, resulting in a decrease in proinflammatory gene expression. Mechanistically, Pfkfb3 ablation or inhibition with a Pfkfb3 inhibitor AZ26 suppresses LPS-induced proinflammatory gene expression via the NF-κB signaling pathway. In summary, our study reveals the critical role of Pfkfb3 in LPS-induced sepsis via reprogramming macrophage metabolism and regulating proinflammatory gene expression. Therefore, PFKFB3 is a potential target for the prevention and treatment of inflammatory diseases such as sepsis.