Effects and early diagnostic value of lncRNA H19 on sepsis-induced acute lung injury

Abstract

Sepsis is an immune disease induced by microbial invasion. The molecular mechanism and value of long non-coding H19 (lncRNA H19) in sepsis remain largely unknown. The present study aimed to investigate the effects and early diagnostic value of lncRNA H19 on sepsis-induced acute lung injury (ALI). Serum samples from 85 septic patients and 76 healthy individuals were collected, and the expression of lncRNA H19 was assessed by the quantitative polymerase chain reaction (qPCR). Sprague-Dawley (SD) rats were subjected to cecal ligation and puncture (CLP) in order to construct models of sepsis-induced ALI. A total of 18 successfully modeled rats were randomly allocated into an lncRNA H19-ad group and a model group, and another 9 healthy SD rats from the same batch were selected as a control group. The samples of serum and lung tissue were collected. lncRNA H19 expression was quantified by qPCR, and levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), IL-17, caspase-3, caspase-9, B-cell lymphoma-2 (Bcl-2), and BCL2-associated X (Bax) were measured by western blotting. A receiver operating characteristic (ROC) curve was employed to assess the diagnostic value of lncRNA H19 for septic patients. lncRNA H19 was downregulated in sepsis. Upregulation of lncRNA H19 inhibited TNF-α, IL-6, IL-17, caspase-3, caspase-9 and Bax and increased Bcl-2. The AUC of lncRNA H19 for early diagnosis of sepsis was 0.8197 (95% CI, 0.77 to 0.91). lncRNA H19 alleviated sepsis-induced ALI by inhibiting pulmonary apoptosis and inflammation, serving as a biochemical marker and therapeutic target for sepsis.

Keywords: acute lung injury; early diagnosis; long non-coding RNA H19; sepsis.

Figure 1

lncRNA H19 is expressed at a low level in sepsis. (A) lncRNA H19 was downregulated in the serum of septic patients; ^***P<0.001. (B) lncRNA H19 was down-regulated in the serum of septic rats; ^***P<0.001 vs. the control group. (C) lncRNA H19 was downregulated in the pulmonary tissue of septic rats; ^***P<0.001 vs. the control group. lncRNA, long non-coding RNA.

Figure 2

ROC analysis of lncRNA H19 for early diagnosis of sepsis. (A) lncRNA H19 for early diagnosis of sepsis, n=85; AUC=0.8197; 95% CI, 0.77 to 0.91. (B) lncRNA H19 for diagnosis of septic patients with ALI, n=49; AUC=0.9141; 95% CI, 0.87 to 0.96. (C) lncRNA H19 for diagnosis of septic patients without ALI, n=36; AUC=0.8399; 95% CI, 0.77 to 0.91. ROC, receiver operating characteristic; lncRNA, long non-coding RNA; ALI, acute lung injury; AUC, area under the curve; CI, confidence interval.

Figure 3

Upregulation of lncRNA H19 reduces pulmonary inflammation and apoptosis in septic rats. (A) lncRNA H19 downregulated caspase-3, caspase-9, Bax and upregulated Bcl-2. (B) Upregulation of lncRNA H19 reduced TNF-α, IL-6 and IL-17 in pulmonary tissue. (C) Upregulation of lncRNA H19 reduced TNF-α, IL-6 and IL-17 in serum. (D) Western blotting of caspase-3, caspase-9, Bax, Bcl-2, TNF-α, IL-6 and IL-17. ^*P<0.05 vs. the control group; ^#P<0.05 vs. the model group. lncRNA, long non-coding RNA; Bax, BCL2-associated X; Bcl-2, B-cell lymphoma-2; TNF-α, tumor necrosis factor-α; IL, interleukin.

Figure 4

Upregulation of lncRNA H19 improves pulmonary function in septic rats. (A) Effects of lncRNA H19 on SOD. (B) Effects of lncRNA H19 on MDA. (C) Effects of lncRNA H19 on MPO. (D) Effects of lncRNA H19 on W/D. ^***P<0.001 vs. the control group; ^###P<0.001 vs. the model group. lncRNA, long non-coding RNA; SOD, superoxide dismutase; MDA, malondialdehyde; MPO, myeloperoxidase; W/D, wet to dry.

Figure 5

miR-152-3p is the target gene of lncRNA H19. (A) lncRNA H19 was capable of binding to miR-152-3p. (B) Dual-luciferase reporter gene assay. ^*P<0.05 vs. the NC-mimics group. (C) Upregulation of lncRNA H19 suppressed the expression miR-152-3p in serum; ^*P<0.05 vs. the control group. (D) Upregulation of lncRNA H19 suppressed miR-152-3p in cells; ^*P<0.05 vs. the control group. lncRNA, long non-coding RNA; miR, microRNA.