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Pharmacologic interventions to halt/reverse the vascular remodeling and right ventricular dysfunction in pulmonary arterial hypertension (PAH) remains an unmet need. We previously demonstrated extracellular nicotinamide phosphoribosyltransferase (eNAMPT) as a DAMP (damage-associated molecular pattern protein) contributing to PAH pathobiology via TLR4 ligation. We examined the role of endothelial cell (EC)-specific eNAMPT in experimental PH and an eNAMPT-neutralizing mAb as a therapeutic strategy to reverse established PH. Hemodynamic/echocardiographic measurements and tissue analyses were performed in Sprague Dawley rats exposed to 10% hypoxia/Sugen (three weeks) followed by return to normoxia and weekly intraperitoneal delivery of the eNAMPT mAb (1 mg/kg). WT C57BL/6J mice and conditional EC-cNAMPTec-/- mice were exposed to 10% hypoxia (three weeks). Biochemical and RNA sequencing studies were performed on rat PH lung tissues and human PAH PBMCs. Hypoxia/Sugen-exposed rats exhibited multiple indices of severe PH (right ventricular systolic pressure, Fulton index), including severe vascular remodeling, compared to control rats. PH severity indices and plasma levels of eNAMPT, IL-6, and TNF-α were all significantly attenuated by eNAMPT mAb neutralization. Compared to hypoxia-exposed WT mice, cNAMPTec-/- KO mice exhibited significantly reduced PH severity and evidence of EC to mesenchymal transition (EndMT). Finally, biochemical and RNAseq analyses revealed eNAMPT mAb-mediated rectification of dysregulated inflammatory signaling pathways (TLR/NF-κB, MAP kinase, Akt/mTOR) and EndMT in rat PH lung tissues and human PAH PBMCs. These studies underscore EC-derived eNAMPT as a key contributor to PAH pathobiology and support the eNAMPT/TLR4 inflammatory pathway as a highly druggable therapeutic target to reduce PH severity and reverse PAH.

Necrotizing enterocolitis (NEC) is the most common gastrointestinal emergency of prematurity. Postulated mechanisms leading to inflammatory necrosis of the ileum and colon include activation of the pathogen recognition receptor Toll-like receptor 4 (TLR4) and decreased levels of transforming growth factor beta (TGFβ). Extracellular nicotinamide phosphoribosyltransferase (eNAMPT), a novel damage-associated molecular pattern (DAMP), is a TLR4 ligand and plays a role in a number of inflammatory disease processes. To test the hypothesis that eNAMPT is involved in NEC, an eNAMPT-neutralizing monoclonal antibody, ALT-100, was used in a well-established animal model of NEC. Preterm Sprague–Dawley pups delivered prematurely from timed-pregnant dams were exposed to hypoxia/hypothermia and randomized to control—foster mother dam-fed rats, injected IP with saline (vehicle) 48 h after delivery; control + mAB—foster dam-fed rats, injected IP with 10 µg of ALT-100 at 48 h post-delivery; NEC—orally gavaged, formula-fed rats injected with saline; and NEC + mAb—formula-fed rats, injected IP with 10 µg of ALT-100 at 48 h. The distal ileum was processed 96 h after C-section delivery for histological, biochemical, molecular, and RNA sequencing studies. Saline-treated NEC pups exhibited markedly increased fecal blood and histologic ileal damage compared to controls (q < 0.0001), and findings significantly reduced in ALT-100 mAb-treated NEC pups (q < 0.01). Real-time PCR in ileal tissues revealed increased NAMPT in NEC pups compared to pups that received the ALT-100 mAb (p < 0.01). Elevated serum levels of tumor necrosis factor alpha (TNFα), interleukin 6 (IL-6), interleukin-8 (IL-8), and NAMPT were observed in NEC pups compared to NEC + mAb pups (p < 0.01). Finally, RNA-Seq confirmed dysregulated TGFβ and TLR4 signaling pathways in NEC pups that were attenuated by ALT-100 mAb treatment. These data strongly support the involvement of eNAMPT in NEC pathobiology and eNAMPT neutralization as a strategy to address the unmet need for NEC therapeutics. [ABSTRACT FROM AUTHOR]

Objective  Point-of-care ultrasound (POC US) has been increasingly used by intensive care physicians. Growing use of POC US necessitates defining distinct clinical indications for its application, as well as structured POC US training programs. Homogeneous approach to POC US education combined with rigorous quality assurance should further enable POC US to become standard-of-care clinical tool. This study aimed to present the first, innovative, and structured POC US program in neonatal–perinatal medicine field. In addition, we reviewed the availability of the POC US training programs across different medical specialties. Study Design  Available English-language publications on POC US training programs in general and neonatal–perinatal medicine were reviewed in this study. Discussion  Mounting body of evidence suggests improved procedural completion rates, as well as clinical decision making with the use of POC US. However, limited research supported the existence of structured, comprehensive POC US programs. It was recognized that medical institutions need to develop syllabuses, teach, and credential increasing number of health care professionals in the use of POC US. We defined intuitive educational strategy that encompasses POC US clinical indications, educational curriculum, scanning protocols, competence evaluation, and finally credentialing process. In addition, we offered description of the imaging quality assurance, as well as POC US coding, and reimbursement. Conclusion  Future efforts need to be dedicated to the ongoing development of neonatal POC US as a clinical instrument. It should allow for eventual paradigm change and improved effectiveness in management of critically ill neonates. [ABSTRACT FROM AUTHOR]