PFKFB3 promotes endotoxemia-induced myocardial dysfunction through inflammatory signaling and apoptotic induction.

Cardiac dysfunction is a vital complication during endotoxemia (ETM). Accumulating evidence suggests that enhanced glycolytic metabolism promotes inflammatory and myocardial diseases. In this study, we performed deep mRNA sequencing analysis on the hearts of control and lipopolysaccharide (LPS)-challenged mice (40 mg/kg, i.p.) and identified that the glycolytic enzyme, 6-phosphofructo-2-kinase (PFK-2)/fructose-2,6-bisphosphatase 3 (PFKFB3) might play an indispensable role in ETM-induced cardiac damage. Quantitative real-time PCR validated the transcriptional upregulation of PFKFB3 in the myocardium of LPS-challenged mice and immunoblotting and immunostaining assays confirmed that LPS stimulation markedly increased the expression of PFKFB3 at the protein level both in vivo and in vitro. The potent antagonist 3-(3pyridinyl)-1-(4-pyridinyl)-2-propen-1-one (3PO) was used to block PFKFB3 activity in vivo (50 mg/kg, i.p.) and in vitro (10 μM). Echocardiographic analysis and TUNEL staining showed that 3PO significantly alleviated LPS-induced cardiac dysfunction and apoptotic injury in vivo. 3PO also suppressed the LPS-induced secretion of tumor necrosis factor-α, interleukin (IL)-1β, IL-6 and lactate in the serum, in addition to lactate in the myocardium. PFKFB3 inhibition also diminished the nuclear translocation and phosphorylation of transcription factor nuclear factor-κB (NF-κB) in both adult cardiomyocytes and HL-1 cells. Furthermore, immunoblotting analysis showed that 3PO inhibited LPS-induced apoptotic induction in cardiomyocytes. Taken together, these findings demonstrate that PFKFB3 participates in LPS-induced cardiac dysfunction via mediating inflammatory and apoptotic signaling pathway.

Tian W ，Guo HS ，Li CY ，Cao W ，Wang XY ，Mo D ，Hao XW ，Feng YD ，Sun Y ，Lei F ，Zhang HN ，Zhao MG ，Li XQ ... -  《-》

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.

Wang L ，Cao Y ，Gorshkov B ，Zhou Y ，Yang Q ，Xu J ，Ma Q ，Zhang X ，Wang J ，Mao X ，Zeng X ，Su Y ，Verin AD ，Hong M ，Liu Z ，Huo Y ... -  《-》

Small-molecule inhibition of 6-phosphofructo-2-kinase activity suppresses glycolytic flux and tumor growth.

Clem B ，Telang S ，Clem A ，Yalcin A ，Meier J ，Simmons A ，Rasku MA ，Arumugam S ，Dean WL ，Eaton J ，Lane A ，Trent JO ，Chesney J ... -  《MOLECULAR CANCER THERAPEUTICS》

3PO inhibits inflammatory NFκB and stress-activated kinase signaling in primary human endothelial cells independently of its target PFKFB3.

Wik JA ，Lundbäck P ，la Cour Poulsen L ，Haraldsen G ，Skålhegg BS ，Hol J ... -  《PLoS One》

Small molecule inhibition of 6-phosphofructo-2-kinase suppresses t cell activation.

Telang S ，Clem BF ，Klarer AC ，Clem AL ，Trent JO ，Bucala R ，Chesney J ... -  《Journal of Translational Medicine》