Correlation of fibrinogen-like protein 2 with disease progression in patients with severe acute pancreatitis

FGL1 and FGL2: emerging regulators of liver health and disease

Liver disease is a complex group of diseases with high morbidity and mortality rates, emerging as a major global health concern. Recent studies have highlighted the involvement of fibrinogen-like proteins, specifically fibrinogen-like protein 1 (FGL1) and fibrinogen-like protein 2 (FGL2), in the regulation of various liver diseases. FGL1 plays a crucial role in promoting hepatocyte growth, regulating lipid metabolism, and influencing the tumor microenvironment (TME), contributing significantly to liver repair, non-alcoholic fatty liver disease (NAFLD), and liver cancer. On the other hand, FGL2 is a multifunctional protein known for its role in modulating prothrombin activity and inducing immune tolerance, impacting viral hepatitis, liver fibrosis, hepatocellular carcinoma (HCC), and liver transplantation. Understanding the functions and mechanisms of fibrinogen-like proteins is essential for the development of effective therapeutic approaches for liver diseases. Additionally, FGL1 has demonstrated potential as a disease biomarker in radiation and drug-induced liver injury as well as HCC, while FGL2 shows promise as a biomarker in viral hepatitis and liver transplantation. The expression levels of these molecules offer exciting prospects for disease assessment. This review provides an overview of the structure and roles of FGL1 and FGL2 in different liver conditions, emphasizing the intricate molecular regulatory processes and advancements in targeted therapies. Furthermore, it explores the potential benefits and challenges of targeting FGL1 and FGL2 for liver disease treatment and the prospects of fibrinogen-like proteins as biomarkers for liver disease, offering insights for future research in this field.

Soluble Fibrinogen-Like Protein 2 Downregulation and Th17/Treg Imbalance in a Taurocholate-Induced Murine Experimental Model of Severe Acute Pancreatitis

BACKGROUND

Severe acute pancreatitis (SAP) is associated with tremendous systemic inflammation, T-helper 17 (Th17) cells, and regulatory T (Treg) cells play an essential role in the inflammatory responses. Meanwhile, soluble fibrinogen-like protein 2 (Sfgl2) is a critical immunosuppressive effector cytokine of Treg cells and modulates immune responses. However, the impact of SAP induction on Sfgl2 expression and the role of Sfgl2 in immunomodulation under SAP conditions are largely unknown.

METHODS

A taurocholate-induced mouse SAP model was established. The ratios of CD4+CD25+Foxp3+ Treg cells or CD4+IL-17+ Th17 cells in blood and pancreatic tissues as well as surface expression of CD80, CD86, and major histocompatibility complex class II (MHC-II) were determined by flow cytometry. Gene mRNA expression was determined by qPCR. Serum amylase and soluble factors were quantitated by commercial kits. Bone marrow-derived dendritic cells (DCs) were generated, and NF-κB/p65 translocation was measured by immunofluorescence staining.

RESULTS

SAP induction in mice decreased the Th17/Treg ratio in the pancreatic tissue and increased the Th17/Treg ratio in the peripheral blood. In addition, SAP was associated with a reduced level of Sfgl2 in the pancreatic tissue and blood: higher levels of serum IL-17, IL-2, IFN-α, and TNF-α, and lower levels of serum IL-4 and IL-10. Furthermore, the SAP-induced reduction in Sfgl2 expression was accompanied by dysregulated maturation of bone marrow-derived DCs.

CONCLUSIONS

SAP causes reduced Sfgl2 expression and Th17/Treg imbalance, thus providing critical insights for the development of Sfgl2- and Th17/Treg balance-targeted immunotherapies for patients with SAP.

Pancreatic β-cell dysfunction in type 2 diabetes: Implications of inflammation and oxidative stress

Insulin resistance and pancreatic β-cell dysfunction are major pathological mechanisms implicated in the development and progression of type 2 diabetes (T2D). Beyond the detrimental effects of insulin resistance, inflammation and oxidative stress have emerged as critical features of T2D that define β-cell dysfunction. Predominant markers of inflammation such as C-reactive protein, tumor necrosis factor alpha, and interleukin-1β are consistently associated with β-cell failure in preclinical models and in people with T2D. Similarly, important markers of oxidative stress, such as increased reactive oxygen species and depleted intracellular antioxidants, are consistent with pancreatic β-cell damage in conditions of T2D. Such effects illustrate a pathological relationship between an abnormal inflammatory response and generation of oxidative stress during the progression of T2D. The current review explores preclinical and clinical research on the patho-logical implications of inflammation and oxidative stress during the development of β-cell dysfunction in T2D. Moreover, important molecular mechanisms and relevant biomarkers involved in this process are discussed to divulge a pathological link between inflammation and oxidative stress during β-cell failure in T2D. Underpinning the clinical relevance of the review, a systematic analysis of evidence from randomized controlled trials is covered, on the potential therapeutic effects of some commonly used antidiabetic agents in modulating inflammatory makers to improve β-cell function.

Presence and activity of Fibrinogen like protein 2 in platelets

BACKGROUND

Fibrinogen-like protein 2 (FGL2) is a serine protease capable of converting prothrombin into thrombin (i.e., prothrombinase-like activity) while bypassing the classic coagulation cascade. It has been reported to be expressed by mononuclear blood cells and endothelial cells. There are multiple reports that FGL2 supports tumor development and metastasis. However, in the blood, the origin and functional significance of FGL2 has not been established.

OBJECTIVE

To determine if FGL2, a malignancy related enzyme, is present in platelets.

METHODS

Peripheral blood samples were collected in K2 EDTA tubes. Blood cells and platelets were separated and thoroughly washed to produce plasma-free samples. Procoagulant activity was measured in the cell lysates using a thrombin generation test or an adjusted prothrombin time (PT) test in plasma deficient of factor X. The findings were further supported by confocal microscopy, immunoprecipitation, flow cytometry, enzyme-linked immunosorbent assays and specific inhibition assays.

RESULTS

FGL2 protein was readily detected in platelets. Also, despite being expressed by lymphocytes, FGL2 prothrombinase-like activity was solely detected in platelet samples, but not in white blood cell samples. Quiescent platelets were shown to contain the FGL2 protein in an active form. Upon activation, platelets secreted the active FGL2 into the milieu.

CONCLUSIONS

Active FGL2 is found in platelets. This suggests another role for the involvement of platelets in malignancies.

Gene Expression Profiling: Identification of Novel Pathways and Potential Biomarkers in Severe Acute Pancreatitis

BACKGROUND

Determining the risk of developing severe acute pancreatitis (AP) on presentation to hospital is difficult but vital to enable early management decisions that reduce morbidity and mortality. The objective of this study was to determine global gene expression profiles of patients with different acute pancreatitis severity to identify genes and molecular mechanisms involved in the pathogenesis of severe AP.

STUDY DESIGN

AP patients (n = 87) were recruited within 24 hours of admission to the Emergency Department and were confirmed to exhibit at least 2 of the following features: (1) abdominal pain characteristic of AP, (2) serum amylase and/or lipase more than 3-fold the upper laboratory limit considered normal, and/or (3) radiographically demonstrated AP on CT scan. Severity was defined according to the Revised Atlanta classification. Thirty-two healthy volunteers were also recruited and peripheral venous blood was collected for performing RNA-Seq.

RESULTS

In severe AP, 422 genes (185 upregulated, 237 downregulated) were significantly differentially expressed when compared with moderately severe and mild cases. Pathway analysis revealed changes in specific innate and adaptive immune, sepsis-related, and surface modification pathways in severe AP. Data-driven approaches revealed distinct gene expression groups (endotypes), which were not entirely overlapping with the clinical Atlanta classification. Importantly, severe and moderately severe AP patients clustered away from healthy controls, whereas mild AP patients did not exhibit any clear separation, suggesting distinct underlying mechanisms that may influence severity of AP.

CONCLUSION

There were significant differences in gene expression affecting the severity of AP, revealing a central role of specific immunological pathways. Despite the existence of patient endotypes, a 4-gene transcriptomic signature (S100A8, S100A9, MMP25, and MT-ND4L) was determined that can predict severe AP with an accuracy of 64%.

Serum soluble fibrinogen-like protein 2 concentration predicts delirium after acute pancreatitis

OBJECTIVE

Inflammation can cause delirium. Soluble fibrinogen-like protein 2 (sFGL2) is a modulator of the immune response and more recently found to be a biomarker for brain injury. This study was designed to discover the predictive capability of serum sFGL2 concentrations for delirium after acute pancreatitis (AP).

MATERIALS AND METHODS

In this prospective, observational study, serum sFGL2 concentrations were quantified in 184 healthy controls and in 184 AP patients. Disease severity was assessed by Acute Physiology and Chronic Health Care Evaluation II score, Ranson score, multiple organ dysfunction score, and sequential organ failure assessment score. Delirium was recorded during hospital stay. Predictors of delirium were identified using multivariate analysis.

RESULTS

Serum sFGL2 concentrations were substantially higher in AP patients than in controls. Serum sFGL2 concentrations were intimately correlated with the preceding severity parameters. Serum sFGL2 and the aforementioned severity parameters were independent predictors for delirium. Under receiver operating characteristic curve, the discriminatory ability of serum sFGL2 was equivalent to those of the above-mentioned severity parameters. Moreover, serum sFGL2 dramatically improved the predictive value of the aforementioned severity parameters.

CONCLUSIONS

Elevation of serum sFGL2 concentrations is strongly associated with the AP severity and has the potential to distinguish delirium after AP.

The relationship between serum fibrinogen-like protein 2 concentrations and 30-day mortality of patients with traumatic brain injury

BACKGROUND

Fibrinogen-like protein 2 (FGL2) is an inflammatory procoagulant protein. We discerned the impact of serum FGL2 on trauma severity and 30-day mortality in patients with traumatic brain injury (TBI).

METHODS

A total of 114 severe TBI patients were subjected to assessment of trauma severity using the Glasgow coma scale (GCS). Measurement of the serum concentrations of FGL2 was done. 114 matched control subjects for their age and sex were included for comparison of serum concentration of FGL2.

RESULTS

The concentration of FGL2 was dramatically increased in the patients as compared with the control subjects. FGL2 concentration was inversely correlated with GCS score among the patients. The non-survivors within 30 days exhibited substantially higher FGL2 concentrations than the alive. FGL2 concentrations discriminated the patients at risk of 30-day death with significantly high area under receiver operating characteristic curve. Serum FGL2 emerged as an independent predictor for mortality and overall survival at 30 days after head trauma.

CONCLUSIONS

Serum FGL2 is a promising biomarker for assessing the severity and prognosis in severe TBI.

Adenovirus-mediated artificial miRNA targetting fibrinogen-like protein 2 attenuates the severity of acute pancreatitis in mice

Severe acute pancreatitis (SAP) remains to be challenging for its unpredictable inflammatory progression from acute pancreatitis to SAP. Apoptosis is an important pathology of SAP. Fibrinogen-like protein 2 (FGL2) has been reported to be involved in apoptosis. The present study aimed to explore the therapeutic effect of an adenovirus-mediated artificial miRNA targetting FGL2 (Ad-FGL2-miRNA) in taurocholate-induced murine pancreatitis models. Sodium taurocholate was retrogradely injected into the biliopancreatic ducts of the C57/BL mice to induce SAP. FGL2 expression was measured with reverse transcription-PCR, Western blotting, and immunohistochemical staining. ELISA was used to detect the activity of amylase and the concentrations of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). In addition, the mRNA levels of TNF-α and IL-1β were also detected. Finally, apoptosis was assessed by terminal deoxynucleotidyl transferase mediated dUTP-biotin nick-end labeling (TUNEL) method and Western blotting. Ad-FGL2-miRNA significantly suppressed FGL2 expression and alleviated pancreatic injury. Also, Ad-FGL2-miRNA markedly inhibited a post-SAP increase in the activation of TNF-α and IL-1β. Finally, pretreatment with Ad-FGL2-miRNA ameliorated apoptosis at the early stage of SAP by modulating cleaved caspase-3 and therefore played a protective role. These results indicated that FGL2 might be a promising target for attenuating the severity of SAP and adenovirus-mediated artificial miRNAs targetting FGL2 represented a potential therapeutic approach for the treatment of SAP.

Clinical effects of involvement of a psychologist in nursing care of patients with severe acute pancreatitis

AIM: To investigate the clinical effects and application value of involvement of a psychologist in the nursing care of patients with severe acute pancreatitis (SAP).

METHODS: A total of 162 patients diagnosed with SAP from August 2013 to August 2014 at our hospital were randomly divided into two groups: an experimental group (n = 82) and a control group (n = 80). The control group received routine care, and the experimental group received both routine care and psychological intervention by a psychologist. Effect of treatment, hospitalization time, patient compliance, and anxiety [Self-rating Anxiety Scale (SAS)] were compared for the two groups.

RESULTS: Cure rate in the experimental group (96.3%) was significantly higher than that in the control group (87.5%) (P < 0.05). Patient compliance and degree of satisfaction for nursing in the experimental group were significantly higher than those in the control group. The length of hospitalization time, anxiety scores, and recurrence rate were significantly lower than those in the control group (P < 0.05).

CONCLUSION: Involvement of a psychologist in nursing care significantly enhances patient compliance, reduces hospitalization time and improves negative emotions in SAP patients.

flg2 as a potential biomarker of acute cerebral ischemic-reperfusion injury

Cerebral ischemic-reperfusion injury as an inflammatory and microcirculation dysfunction pathological condition negatively affects the clinical outcome of stroke patients. The novel inflammatory procoagulant protein fgl2 has been reported to play a role in some inflammatory and coagulation dysregulation diseases. This study aimed to examine the relationship between fgl2 expression and infarct size in an acute cerebral ischemic-reperfusion rat model. We studied fgl2 mRNA and protein expressions in cerebral tissue and peripheral macrophages, and the expressions of several inflammatory factors (TNF-α, IL-1β, MCP-1, and IL-8) in serum samples from rats with acute cerebral ischemic-reperfusion injury. Fiber microthrombosis in situ contributed to the microvascular thrombosis in acute cerebral ischemic-reperfusion injury, and fgl2 expression tended to strongly correlate with cerebral infarct size. The expression levels of the other inflammatory factors significantly increased but weakly correlated with cerebral infarct size. These findings support the potential of fgl2 level as a novel biomarker of acute cerebral ischemic-reperfusion injury.