Role of neutrophil extracellular trap formation in liver cirrhosis and sarcopenia

Background and Aims Sarcopenia is a frequent complication of liver cirrhosis, but it can also occur independently from any underlying cause. The immune system plays an important role in the pathogenesis of both liver cirrhosis and sarcopenia. Neutrophil extracellular trap (NET) formation has been linked to chronic inflammation. The function of NETs can be altered in people with liver cirrhosis, however, NET formation of neutrophils in patients with sarcopenia has not been studied yet. Here we aimed to examine if NET formation is altered in patients with sarcopenia.

Method Neutrophils from 36 patients were isolated with and stimulated with heat-inactivated E. coli (250 bacteria/cell), phorbol 12-myristate 13-acetate (PMA) (100nM) or incubation medium in duplicates for 2 hours at 37°C. Cells were fixed with paraformaldehyde and stained with 4′,6-diamidino-2-phenylindole (DAPI) (Life Technologies, Carlsbad, CA, USA). Pictures of 10 random fields of vision per slide were taken. DANA (DNA Area and NETosis Analysis) algorithm was used to quantify the percentage of NET formation per patient. Kruskal-Wallis-Test was performed for each condition (incubated, E. Coli, PMA). Sarcopenia was diagnosed by the EWGSOP 2010 criteria.

Results 18 patients with liver cirrhosis+ sarcopenia, 11 with liver cirrhosis without sarcopenia and 7 with sarcopenia without liver cirrhosis were studied. Mean age of patients with liver cirrhosis and sarcopenia was 56,4+/- 11,6; of patients with liver cirrhosis without sarcopenia 62,8+/- 9,2 years, and of patients with sarcopenia without cirrhosis 60,1+/-10,1 years (p=0,308). Gender was also not different between the groups (p=0.150). No difference in NET formation was observed between the three groups ([Table 1]).

Tab. 1

	cirrhosis+ sarcopenia	cirrhosis w/o sarcopenia	sarcopenia w/o cirrhosis
unstimulated	10,64+/− 11,15	12,59+/− 10,78	31,84+/− 28,92	0.177
stimulated E.coli	28,82+/− 20,62	25,37+/− 19,73	32,57+/− 29,9	0.924
stimulated PMA	51,27+/− 27,34	57,41+/−19,79	53,75+/−24,69	0.907

Conclusion Artificial intelligence can be used for standardized and efficient analysis of NET formation. NET formation was not associated with sarcopenia in this study, however, the small sample size warrants further investigations of this topic. [Table 1]: Percentage of NET formation

Publication History

Article published online:
26 August 2022