miR-141 is negatively correlated with TLR4 in neonatal sepsis and regulates LPS-induced inflammatory responses in monocytes

Diagnostic capacity of miRNAs in neonatal sepsis: a systematic review and meta-analysis

BACKGROUND

Neonatal sepsis is the third leading cause of mortality during the neonatal period, with manifestations atypical and obscure. But the gold standard-blood culture test, requiring 3-5 days, makes it difficult to unveil the final pathogen and leads to the increasing ratio of false-negative results. The empirical method is consulting traditional biomarkers, such as procalcitonin (PCT), C-reactive protein (CRP), and white blood cell count. However, they are not specific for neonate in diagnostic capacity, especially for infants within three days after delivery, so more novel biomarkers are urgently needed to assist diagnosing neonatal sepsis. microRNAs (miRNAs) have been widely studied in recent years for their diagnostic and prognostic values in different diseases and we conducted a meta-analysis of miRNAs on the topic that whether they are potentially novel biomarkers in early detection of neonatal sepsis.

OBJECTIVES

The purpose of the study was to assess whether circulating miRNAs could be used as potential biomarkers for neonatal sepsis, including early and late-onset neonatal sepsis, then calculate their overall accuracy (OA) via meta-analysis.

METHODS

PubMed, Cochrane Library, Embase, Web of Science, Scopus, and Ovid databases were retrieved; data cutoff for this analysis was 15 January 2023. Methodological quality assessment of included studies was performed through the Quality in Prognostic Studies tool. Corresponding 95% confidence interval (95%CI) was calculated to present miRNAs' diagnostic value including the pooled sensitivity (Sen), specificity (Spe), positive or negative likelihood ratios (PLR or NLR), diagnostic odds ratio (DOR), and area under the curve (AUC). Differences in OA between the septic group and non-septic group were compared using Chi-square test.

RESULTS

After identification, 16 records out of 11 selected articles were eligible for systematic review of miRNAs and four records for PCT; the case group for miRNAs included 945 neonatal sepsis cases; contrast group included 190 respiratory tract infections or pneumonia cases, 60 systemic inflammatory response syndrome (SIRS) cases and 559 healthy neonates. The pooled Sen, Spe, and DOR of miRNAs were 0.87 (95%CI 0.81-0.91), 0.79 (95%CI 0.71-0.85), and 24 (95%CI 12-50), respectively. The pooled Sen, Spe, and DOR of PCT were 0.92 (95%CI 0.83-0.96), 0.64 (95%CI 0.56-0.70), and 20 (95%CI, 7-56), respectively. The OA value of miRNAs was 80.38% and that of PCT was 77.36%, which were not statistically significant difference (p = .13) after the Chi-square test. In addition, no significant publication bias was indicated (p = .92).

CONCLUSIONS

Circulating miRNA levels could be applied as diagnostic biomarkers in neonatal sepsis.

MiRNAs as biomarkers for diagnosis of neonatal sepsis: a systematic review and meta-analysis

BACKGROUND

The relationship between circulating miRNAs and neonatal sepsis and the mechanism of action are still unclear at this time. Therefore, the potential diagnostic role of miRNAs in neonatal sepsis (NS) was studied through meta-analysis.

METHOD

Web of Science, Cochrane Library, PubMed, and Embase are retrieved, supplemented by manual search, and the search was conducted to find related studies without time limit until May 2022.The quality of the literature was assessed via QUADAS criteria and meta-analyzed via Stata 11.0 software, including the assessment of specificity, sensitivity, likelihood ratio and diagnostic odds ratio. Then, sensitivity analysis and heterogeneity testing were conducted, and finally, the summary receiver operating characteristics (SROC) curve was drawn.

RESULT

This study included 14 articles, including 20 miRNAs and 1597 newborns(control group: 727 and case group: 870). Among them, one article was of low quality, three articles were of high quality, and the rest were of medium quality. According to the results of random effects model analysis, the pooled specificity and sensitivity of miRNA for the diagnosis of NS were 0.83 (95%CI: 0.79-0.87) and 0.76 (95%CI: 0.72-0.80), respectively. And negative likelihood ratio, positive likelihood ratio, and diagnostic odds ratio were 0.29 (95%CI: 0.24-0.34), 4.51 (95%CI: 3.52-5.78), and 15.81 (95%CI: 10.71-23.35), respectively. The area under the SROC curve was 0.86, and there was no evidence publication bias detected in the funnel plot.

CONCLUSION

Circulating miRNAs may be very useful in the development of early diagnostic strategies for neonatal sepsis.

Transcriptomic and Bioinformatic Analyses Identifying a Central Mif-Cop9-Nf-kB Signaling Network in Innate Immunity Response of Ciona robusta

The Ascidian C. robusta is a powerful model for studying innate immunity. LPS induction activates inflammatory-like reactions in the pharynx and the expression of several innate immune genes in granulocyte hemocytes such as cytokines, for instance, macrophage migration inhibitory factors (CrMifs). This leads to intracellular signaling involving the Nf-kB signaling cascade that triggers downstream pro-inflammatory gene expression. In mammals, the COP9 (Constitutive photomorphogenesis 9) signalosome (CSN) complex also results in the activation of the NF-kB pathway. It is a highly conserved complex in vertebrates, mainly engaged in proteasome degradation which is essential for maintaining processes such as cell cycle, DNA repair, and differentiation. In the present study, we used bioinformatics and in-silico analyses combined with an in-vivo LPS exposure strategy, next-generation sequencing (NGS), and qRT-PCR to elucidate molecules and the temporal dynamics of Mif cytokines, Csn signaling components, and the Nf-κB signaling pathway in C. robusta. A qRT-PCR analysis of immune genes selected from transcriptome data revealed a biphasic activation of the inflammatory response. A phylogenetic and STRING analysis indicated an evolutionarily conserved functional link between the Mif-Csn-Nf-kB axis in ascidian C. robusta during LPS-mediated inflammation response, finely regulated by non-coding molecules such as microRNAs (miRNAs).

Specific microRNAs are associated with fracture healing phases, patient age and multi-trauma

Background

Methods

Results

Conclusion

The Translational Potential of this Article

Modes of action and diagnostic value of miRNAs in sepsis

Sepsis is a clinical syndrome defined as a dysregulated host response to infection resulting in life-threatening organ dysfunction. Sepsis is a major public health concern associated with one in five deaths worldwide. Sepsis is characterized by unbalanced inflammation and profound and sustained immunosuppression, increasing patient susceptibility to secondary infections and mortality. microRNAs (miRNAs) play a central role in the control of many biological processes, and deregulation of their expression has been linked to the development of oncological, cardiovascular, neurodegenerative and metabolic diseases. In this review, we discuss the role of miRNAs in sepsis pathophysiology. Overall, miRNAs are seen as promising biomarkers, and it has been proposed to develop miRNA-based therapies for sepsis. Yet, the picture is not so straightforward because of the versatile and dynamic features of miRNAs. Clearly, more research is needed to clarify the expression and role of miRNAs in sepsis, and to promote the use of miRNAs for sepsis management.

MiR-146a-5p accelerates sepsis through dendritic cell activation and glycolysis via targeting ATG7

To unveil the role and regulatory mechanism of miR-146a-5p in sepsis. A sepsis cell model was established via lipopolysaccharide (LPS)-induction in dendritic cells (DCs). The maturation of DCs was evaluated via flow cytometry. Gene expression was measured through reverse-transcription quantitative polymerase chain reaction (RT-qPCR). The concentrations of inflammation biomarkers were revealed via enzyme-linked immunosorbent assay (ELISA). The pathological and histological changes in lungs in the sepsis mice model were analyzed via hematoxylin and eosin (H&E) staining. In this study, the miR-146a-5p level was elevated in the serum of sepsis patients and LPS-induced DCs but decreased in the serums of cured sepsis patients. Furthermore, miR-146a-5p deletion alleviated the activation of T cells and attenuated the imbalance of Th17/Treg. Besides, ATG7 was validated as a target of miR-146a-5p. ATG7 elevation enhanced lactate production and glucose uptake in LPS-triggered DCs. Additionally, upregulation of ATG7 suppressed the protein levels of phosphorylated adenosine monophosphate-activated protein kinase (p-AMPK), phospho protein kinase B (p-AKT), and phosphorylated signal transducer and activator for transcription 3 (p-STAT3). In addition, miR-146a-5p downregulation alleviated T-cell activation, inflammation, lactate production, and glucose uptake in sepsis mice. Moreover, the lung injury due to sepsis was also attenuated as a result of miR-146a-5p silencing. MiR-146a-5p aggravates sepsis through DCs activation and glycolysis via targeting ATG7.

MicroRNA as an Early Biomarker of Neonatal Sepsis

Sepsis is a major cause of lethality in neonatal intensive care units. Despite significant advances in neonatal care and growing scientific knowledge about the disease, 4 of every 10 infants born in developed countries and suffering from sepsis die or experience considerable disability, including substantial and permanent neurodevelopmental impairment. Pharmacological treatment strategies for neonatal sepsis remain limited and mainly based upon early initiation of antibiotics and supportive treatment. In this context, numerous clinical and serum-based markers have been evaluated for diagnosing sepsis and evaluating its severity and etiology. MicroRNAs (miRNAs) do not encode for proteins but regulate gene expression by inhibiting the translation or transcription of their target mRNAs. Recently, it was demonstrated in adult patients that miRNAs are released into the circulation and that the spectrum of circulating miRNAs is altered during various pathologic conditions, such as inflammation, infection, and sepsis. Here, we summarize current findings on the role of circulating miRNAs in the diagnosis and staging of neonatal sepsis. The conclusions point to substantial diagnostic potential, and several miRNAs have been validated independently by different teams, namely miR-16a, miR-16, miR-96-5p, miR-141, miR-181a, and miR-1184.

Role of macrophages in fetal development and perinatal disorders

In the fetus and the neonate, altered macrophage function has been implicated not only in inflammatory disorders but also in developmental abnormalities marked by altered onset, interruption, or imbalance of key structural changes. The developmental role of macrophages were first noted nearly a century ago, at about the same time when these cells were being identified as central effectors in phagocytosis and elimination of microbes. Since that time, we have made considerable progress in understanding the diverse roles that these cells play in both physiology and disease. Here, we review the role of fetal and neonatal macrophages in immune surveillance, innate immunity, homeostasis, tissue remodeling, angiogenesis, and repair of damaged tissues. We also discuss the possibility of therapeutic manipulation of the relative abundance and activation status of macrophage subsets in various diseases. This article combines peer-reviewed evidence from our own studies with results of an extensive literature search in the databases PubMed, EMBASE, and Scopus. IMPACT: We have reviewed the structure, differentiation, and classification of macrophages in the neonatal period. Neonatal macrophages are derived from embryonic, hepatic, and bone marrow precursors. Macrophages play major roles in tissue homeostasis, innate immunity, inflammation, tissue repair, angiogenesis, and apoptosis of various cellular lineages in various infectious and inflammatory disorders. Macrophages and related inflammatory mediators could be important therapeutic targets in several neonatal diseases.