The angiogenic properties of human adipose-derived stem cells (HASCs) are modulated by the High mobility group box protein 1 (HMGB1) Federico Biscetti a,b, ⁎, Stefano Gentileschi c , Flavio Bertucci b , Maria Servillo c , Vincenzo Arena d , Flavia Angelini b , Egidio Stigliano d , Giuseppina Bonanno e , Giovanni Scambia e , Benedetto Sacchetti f , Luca Pierelli g,h , Raffaele Landolfi i , Andrea Flex b,i a Division of Rheumatology, Institute of Rheumatology & Related Sciences, Fondazione Policlinico Universitario “A. Gemelli”, Catholic University School of Medicine, Rome, Italy b Laboratory of Vascular Biology and Genetics, Department of Medicine, Fondazione Policlinico Universitario “A. Gemelli”, Catholic University School of Medicine, Rome, Italy c Division of Plastic Surgery, Fondazione Policlinico Universitario “A. Gemelli”, Catholic University School of Medicine, Rome, Italy d Department of Pathology, Fondazione Policlinico Universitario “A. Gemelli”, Catholic University School of Medicine, Rome, Italy e Division of Gynecology, Fondazione Policlinico Universitario “A. Gemelli”, Catholic University School of Medicine, Rome, Italy f Department of Science, University ROMA TRE, Rome, Italy g Immunohematology and Transfusion Medicine, San Camillo Forlanini Hospital, Rome, Italy h Department of Experimental Medicine, Sapienza University, Rome, Italy i Department of Internal Medicine, Fondazione Policlinico Universitario “A. Gemelli”, Catholic University School of Medicine, Rome, Italy abstract article info Article history: Received 8 April 2017 Received in revised form 4 September 2017 Accepted 18 September 2017 Available online xxxx Peripheral arterial disease (PAD), is a major health problem. Many studies have been focused on the possibilities of treatment offered by vascular regeneration. Human adipose-derived stem cells (HASCs), multipotent CD34+ stem cells found in the stromal-vascular fraction of adipose tissues, which are capable to differentiate into multiple mesenchymal cell types. The High mobility group box 1 protein (HMGB1) is a nuclear protein involved in angiogenesis. The aim of the study was to define the role of HMGB1 in cell therapy with HASCs, in an animal model of PAD. We induced unilateral ischemia in mice and we treated them with HASCs, with the specific HMGB1-inihibitor BoxA, with HMGB1 protein, and with the specific VEGF inhibitor sFlt1, alternately or concurrently. We measured the blood flow recovery in all mice. Immunohistochemical and ELISA analyses was performed to evaluate the number of vessels and the VEGF tissue content. None auto-amputation occurred and there have been no rejection reactions to the administration of HASCs. Animals co-treated with HASCs and HMGB1 protein had an improved blood flow recovery, compared to HASCs-treated mice. The post-ischemic angiogenesis was reduced when the HMGB1 pathway was blocked or when the VEGF activity was inhibited, in mice co-treated with HASCs and HMGB1. In conclusion, the HASCs treatment can be used in a mouse model of PAD to induce post-ischemic angiogenesis, modulating angiogenesis by HMGB1. This effect is mediated by VEGF activity. Although further data are needed, these findings shed light on possible new cell treatments for patients with PAD. © 2017 Elsevier B.V. All rights reserved. Keywords: HASCs HMGB1 PAD Angiogenesis VEGF 1. Introduction Peripheral arterial disease (PAD), the pathological process of obstruction of the arteries (excluding those of the coronary and cerebral circulation), is a major health problem, affecting over 3% of women and 5% of man over 60 years of age [1]. Its most severe manifestation is the critical limb ischemia (CLI), which is associated with high rates of limb loss, morbidity, and mortality [2]. Besides the traditional medical and surgical approaches to the disease, in recent years many studies have been focused on the possibilities of treatment offered by vascular regeneration [3]. The formation of new blood vessels occurs substantially through two mechanisms: angiogenesis and vasculogenesis. Vasculogenesis refers to the generation of embryonic blood vessels from endothelial progenitor cells (EPCs), or angioblasts; angiogenesis is the process of neovascular- ization during postnatal life, which results from proliferation, migration, and remodeling of fully differentiated vascular endothelial cells (VECs) derived from preexisting blood vessels [4]. In 1997 EPCs have been isolated from human peripheral blood. In vitro, these cells show the capability to differentiate into VECs. These findings suggested that peripheral blood contains cells that can International Journal of Cardiology xxx (2017) xxx–xxx ⁎ Corresponding author at: Division of Rheumatology, Fondazione Policlinico Universitario “A. Gemelli”, Catholic University School of Medicine, L.go A. Gemelli 1, 00168 Rome, Italy. E-mail address: f.biscetti@gmail.com (F. Biscetti). IJCA-25459; No of Pages 8 https://doi.org/10.1016/j.ijcard.2017.09.165 0167-5273/© 2017 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect International Journal of Cardiology journal homepage: www.elsevier.com/locate/ijcard Please cite this article as: F. Biscetti, et al., The angiogenic properties of human adipose-derived stem cells (HASCs) are modulated by the High mobility group box protein 1 (HMGB..., Int J Cardiol (2017), https://doi.org/10.1016/j.ijcard.2017.09.165