Roberto Carnevale1, Valeria Raparelli2, Cristina Nocella1, Simona Bartimoccia3, Marta Novo3, Anna Severino3, Elena De Falco1, Vittoria Cammisotto3, Chiara Pasquale4, Clara Crescioli5, Antonio Sili Scavalli3, Oliviero Riggio4, Stefania Basili3, Francesco Violi6. 1. Department of Medical-Surgical Sciences and Biotechnologies, Sapienza University of Rome, Latina, Italy. 2. Department of Experimental Medicine, Sapienza University of Rome, Rome, Italy. 3. Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Rome, Italy. 4. Department of Clinical Medicine, Center for the Diagnosis and Treatment of Portal Hypertension, Sapienza-University of Rome, Rome, Italy. 5. Department of Movement, Human and Health Sciences, Section of Health Sciences, "Foro Italico" University of Rome, Rome, Italy. 6. Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Rome, Italy. Electronic address: francesco.violi@uniroma1.it.
Abstract
BACKGROUND & AIMS: Patients with cirrhosis display enhanced blood levels of factor VIII, which may result in harmful activation of the clotting system; however, the underlying mechanism is unknown. METHODS: We performed a cross-sectional study in patients with cirrhosis (n=61) and matched controls (n=61) comparing blood levels of factor VIII, von Willebrand factor (vWf), lipopolysaccharide (LPS) and positivity for Escherichia coli DNA. Furthermore, we performed an in vitro study to investigate if LPS, in a concentration range similar to that found in the peripheral circulation of cirrhotic patients, was able to elicit factor VIII secretion from human umbilical vein endothelial cells (HUVEC). RESULTS: Patients with cirrhosis displayed higher serum levels of LPS (55.8 [42.2-79.9] vs. 23.0 [7.0-34.0]pg/ml, p<0.001), factor VIII (172.0 [130.0-278.0] vs. 39.0 [26.0-47.0]U/dl, p<0.0001), vWf (265.0 [185.0-366.0] vs. 57.0 [48.0-65.0]U/dl, p<0.001) and positivity for Escherichia coli DNA (88% vs. 3%, p<0.001, n=34) compared to controls. Serum LPS correlated significantly with factor VIII (r=0.80, p<0.001) and vWf (r=0.63, p<0.001). Only LPS (beta-coefficient=0.70, p<0.0001) independently predicted factor VIII levels. The in vitro study showed that LPS provoked factor VIII and vWf release from HUVEC via formation and secretion of Weibel-Palade bodies, a phenomenon blunted by pre-treating HUVEC with an inhibitor of Toll-like receptor 4. CONCLUSIONS: The study provides the first evidence that LPS derived from gut microbiota increases the systemic levels of factor VIII via stimulating its release by endothelial cells. Lay summary: Cirrhosis is associated with thrombosis in portal and systemic circulation. Enhanced levels of factor VIII have been suggested to play a role but the underlying mechanism is still unclear. Here we show that patients with cirrhosis display a concomitant increase of factor VIII and lipopolysaccharide (LPS) from Escherichia coli and suggest that LPS contributes to the release of factor VIII from endothelial cells.
BACKGROUND & AIMS:Patients with cirrhosis display enhanced blood levels of factor VIII, which may result in harmful activation of the clotting system; however, the underlying mechanism is unknown. METHODS: We performed a cross-sectional study in patients with cirrhosis (n=61) and matched controls (n=61) comparing blood levels of factor VIII, von Willebrand factor (vWf), lipopolysaccharide (LPS) and positivity for Escherichia coli DNA. Furthermore, we performed an in vitro study to investigate if LPS, in a concentration range similar to that found in the peripheral circulation of cirrhotic patients, was able to elicit factor VIII secretion from human umbilical vein endothelial cells (HUVEC). RESULTS:Patients with cirrhosis displayed higher serum levels of LPS (55.8 [42.2-79.9] vs. 23.0 [7.0-34.0]pg/ml, p<0.001), factor VIII (172.0 [130.0-278.0] vs. 39.0 [26.0-47.0]U/dl, p<0.0001), vWf (265.0 [185.0-366.0] vs. 57.0 [48.0-65.0]U/dl, p<0.001) and positivity for Escherichia coli DNA (88% vs. 3%, p<0.001, n=34) compared to controls. Serum LPS correlated significantly with factor VIII (r=0.80, p<0.001) and vWf (r=0.63, p<0.001). Only LPS (beta-coefficient=0.70, p<0.0001) independently predicted factor VIII levels. The in vitro study showed that LPS provoked factor VIII and vWf release from HUVEC via formation and secretion of Weibel-Palade bodies, a phenomenon blunted by pre-treating HUVEC with an inhibitor of Toll-like receptor 4. CONCLUSIONS: The study provides the first evidence that LPS derived from gut microbiota increases the systemic levels of factor VIII via stimulating its release by endothelial cells. Lay summary: Cirrhosis is associated with thrombosis in portal and systemic circulation. Enhanced levels of factor VIII have been suggested to play a role but the underlying mechanism is still unclear. Here we show that patients with cirrhosis display a concomitant increase of factor VIII and lipopolysaccharide (LPS) from Escherichia coli and suggest that LPS contributes to the release of factor VIII from endothelial cells.
Authors: Victor Dong; Maxime Gosselin; Nishita Jagarlamudi; Beverley Kok; Mark G Swain; Jasmohan S Bajaj; Juan G Abraldes; Vladimir Marquez; R Todd Stravitz; Aldo J Montano-Loza; Manuela Merli; Phil Wong; Amanda Brisebois; Puneeta Tandon; Julia Wendon; Scott L Nyberg; François M Carrier; Michael R Lucey; Florence Wong; Jordan J Feld; Constantine J Karvellas; Christopher F Rose; Julien Bissonnette Journal: Can Liver J Date: 2019-12-10