Leukocyte activation primes fibrinogen for proteolysis by mitochondrial oxidative stress

Fibrinogen and tumors

Elevated plasma fibrinogen (Fg) levels consistently correlate with an unfavorable prognosis in various tumor patient cohorts. Within the tumor microenvironment, aberrant deposition and expression of Fg have been consistently observed, interacting with multiple cellular receptors and thereby accentuating its role as a regulator of inflammatory processes. Specifically, Fg serves to stimulate and recruit immune cells and pro-inflammatory cytokines, thereby contributing to the promotion of tumor progression. Additionally, Fg and its fragments exhibit dichotomous effects on tumor angiogenesis. Notably, Fg also facilitates tumor migration through both platelet-dependent and platelet-independent mechanisms. Recent studies have illuminated several tumor-related signaling pathways influenced by Fg. This review provides a comprehensive summary of the intricate involvement of Fg in tumor biology, elucidating its multifaceted role and the underlying mechanisms.

The role of inflammation and antithrombin supplementation on thromboelastographic parameters during veno-venous ECMO for respiratory failure

INTRODUCTION

Extracorporeal membrane oxygenation (ECMO) may act as a driver or propagator of systemic inflammation. In turn, cytokine release can modify thromboelastographic (TEG) tests which are commonly used for anticoagulation monitoring. In this context, antithrombin (AT) supplementation might further modify TEG.

METHODS

This is a pre-specified sub-study of the "Randomized Controlled Trial of Antithrombin Supplementation During Extracorporeal Membrane Oxygenation" study (investigator-initiated, randomized, single-blind, two-arm trial) conducted in two Italian ECMO referral ICUs. Adult patients requiring vv-ECMO for respiratory failure and undergoing unfractioned heparin (UFH) administration were enrolled and randomized whether to receive AT supplementation. Plasma samples for cytokine assay (IL-8, IL-10, IL-6, IL-1β, TNF-α and Pro-ADM) and heparinase TEG were collected from every patient before ECMO start, 24 h and 72 h after ECMO start, before ECMO removal, and 7 days after ECMO removal or upon ICU discharge whichever happened first. AT concentration, coagulation and clinical data were collected before ECMO start and at pre-fixed time points.

RESULTS

Thirty-nine patients were enrolled (21 treatments, 18 controls). TEG-R had a weak-to-moderate positive correlation with IL-8, IL-6, IL-10 and TNF-α and a moderate positive correlation with Pro-ADM. TEG-ANG showed a weak negative correlation with IL-8, IL-6 and TNF-α, while TEG-MA negatively correlated with IL-8, TNF-α and Pro-ADM. AT supplementation seemed to modify the association between TEG-MA and IL-8, IL-10 and Pro-ADM; conversely, AT did not affect the relationship among TEG-R or TEG-ANG and the studied cytokines.

CONCLUSIONS

High concentrations of systemic cytokines correlated with longer reaction times and decreased angle and amplitude at TEG, suggesting that an increase in inflammation is related with hypocoagulability as revealed by thromboelastography.

Postoperative Prognostic Nutritional Index and Fibrinogen Could Well Predict Poor Prognosis of Acute Type A Aortic Dissection Patients After Surgery

INTRODUCTION

Inflammatory and immunological factors play pivotal roles in the prognosis of acute type A aortic dissection. We aimed to evaluate the prognostic values of immune-inflammatory parameters in acute type A aortic dissection patients after surgery.

METHODS

A total of 127 acute type A aortic dissection patients were included. Perioperative clinical data were collected through the hospital's information system. The outcomes studied were delayed extubation, reintubation, and 30-day mortality. Multivariate logistic regression analysis and receiver operating characteristic analysis were used to screen the risk factors of poor prognosis.

RESULTS

Of all participants, 94 were male, and mean age was 51.95±11.89 years. The postoperative prognostic nutritional indexes were lower in delayed extubation patients, reintubation patients, and patients who died within 30 days. After multivariate regression analysis, the postoperative prognostic nutritional index was a protective parameter of poor prognosis. The odds ratios (95% confidence interval) of postoperative prognostic nutritional index were 0.898 (0.815, 0.989) for delayed extubation and 0.792 (0.696, 0.901) for 30-day mortality. Low postoperative fibrinogen could also well predict poor clinical outcomes. The odds ratios (95% confidence interval) of postoperative fibrinogen were 0.487 (0.291, 0.813) for delayed extubation, 0.292 (0.124, 0.687) for reintubation, and 0.249 (0.093, 0.669) for 30-day mortality.

CONCLUSION

Postoperative prognostic nutritional index and postoperative fibrinogen could be two promising markers to identify poor prognosis of acute type A aortic dissection patients after surgery.

Laser-Activatable In Situ Vaccine Enhances Cancer-Immunity Cycle

The immune response in cancer reflects a series of carefully regulated events; however, current tumor immunotherapies typically address a single key aspect to enhance anti-tumor immunity. In the present study, a nanoplatform (Fe3 O4 @IR820@CpG)-based immunotherapy strategy that targets the multiple key steps in cancer-immunity cycle is developed: 1) promotes the release of tumor-derived proteins (TDPs), including tumor-associated antigens and pro-immunostimulatory factors), in addition to the direct killing effect, by photothermal (PTT) and photodynamic therapy (PDT); 2) captures the released TDPs and delivers them, together with CpG (a Toll-like receptor 9 agonist) to antigen-presenting cells (APCs) to promote antigen presentation and T cell activation; 3) enhances the tumor-killing ability of T cells by combining with anti-programmed death ligand 1 antibody (α-PD-L1), which collectively advances the outstanding of the anti-tumor effects on colorectal, liver and breast cancers. The broad-spectrum anti-tumor activity of Fe3 O4 @IR820@CpG with α-PD-L1 demonstrates that optimally manipulating anti-cancer immunity not singly but as a group provides promising clinical strategies.

Pathogenic Role of Fibrinogen in the Neuropathology of Multiple Sclerosis: A Tale of Sorrows and Fears

Multiple sclerosis (MS) is an autoimmune demyelinating neurodegenerative disease of the central nervous system (CNS) due to injury of the myelin sheath by immune cells. The clotting factor fibrinogen is involved in the pathogenesis of MS by triggering microglia and the progress of neuroinflammation. Fibrinogen level is correlated with MS severity; consequently, inhibition of the fibrinogen cascade may reduce MS neuropathology. Thus, this review aimed to clarify the potential role of fibrinogen in the pathogenesis of MS and how targeting of fibrinogen affects MS neuropathology. Accumulation of fibrinogen in the CNS may occur independently or due to disruption of blood-brain barrier (BBB) integrity in MS. Fibrinogen acts as transduction and increases microglia activation which induces the progression of inflammation, oxidative stress, and neuronal injury. Besides, brain fibrinogen impairs the remyelination process by inhibiting the differentiation of oligodendrocyte precursor cells. These findings proposed that fibrinogen is associated with MS neuropathology through interruption of BBB integrity, induction of neuroinflammation, and demyelination with inhibition of the remyelination process by suppressing oligodendrocytes. Therefore, targeting of fibrinogen and/or CD11b/CD18 receptors by metformin and statins might decrease MS neuropathology. In conclusion, inhibiting the expression of CD11b/CD18 receptors by metformin and statins may decrease the pro-inflammatory effect of fibrinogen on microglia which is involved in the progression of MS.

Managing Hemostasis in Space

Human space travel requires exposure to weightlessness, ionizing radiation, isolation, and austerity. A recent report of internal jugular vein thrombosis in astronauts in low Earth orbit confirms that these exposures also affect vascular biology to influence diseases of thrombosis and hemostasis. This brief review summarizes the known influences of space travel on inflammation, blood coagulation, and the cardiovascular system and conceptualizes how they might combine to affect thrombosis and hemostasis. In the event of a major thrombotic or bleeding emergency, it is anticipated that the unique physiological influences of the space environment and logistical limitations of providing medical care in space would require a response that is unique from our current experience. We also look towards the future to discuss lessons learned from our current experiences on Earth and in space.

Oxime blot: A novel method for reliable and sensitive detection of carbonylated proteins in diverse biological systems

Oxidative stress and oxidative protein damage occur in various biological processes and diseases. The carbonyl group on amino acid side chains is the most widely used protein oxidation biomarker. Carbonyl groups are commonly detected indirectly through their reaction with 2,4-dinitrophenylhydrazine (DNPH) and subsequent labeling with an anti-DNP antibody. However, the DNPH immunoblotting method lacks protocol standardization, exhibits technical bias, and has low reliability. To overcome these shortcomings, we have developed a new blotting method in which the carbonyl group reacts with the biotin-aminooxy probe to form a chemically stable oxime bond. The reaction speed and the extent of the carbonyl group derivatization are increased by adding a p-phenylenediamine (pPDA) catalyst under neutral pH conditions. These improvements are crucial since they ensure that the carbonyl derivatization reaction reaches a plateau within hours and increases the sensitivity and robustness of protein carbonyl detection. Furthermore, derivatization under pH-neutral conditions facilitates a good SDS-PAGE protein migration pattern, avoids protein loss by acidic precipitation, and is directly compatible with protein immunoprecipitation. This work describes the new Oxime blot method and demonstrates its use in detecting protein carbonylation in complex matrices from diverse biological samples.

Pump proton inhibitors display anti-tumour potential in glioma

OBJECTIVES

Glioma is one of the most aggressive brain tumours with poor overall survival despite advanced technology in surgical resection, chemotherapy and radiation. Progression and recurrence are the hinge causes of low survival. Our aim is to explain the concrete mechanism in the proliferation and progression of tumours based on tumour microenvironment (TME). The main purpose is to illustrate the mechanism of proton pump inhibitors (PPIs) in affecting acidity, hypoxia, oxidative stress, inflammatory response and autophagy based on the TME to induce apoptosis and enhance the sensitivity of chemoradiotherapy.

FINDINGS

TME is the main medium for tumour growth and progression. Acidity, hypoxia, inflammatory response, autophagy, angiogenesis and so on are the main causes of tumour progress. PPIs, as a common clinical drug to inhibit gastric acid secretion, have the advantages of fast onset, long action time and small adverse reactions. Nowadays, several kinds of literature highlight the potential of PPIs in inhibiting tumour progression. However, long-term use of PPIs alone also has obvious side effects. Therefore, till now, how to apply PPIs to promote the effect of radio-chemotherapy and find the concrete dose and concentration of combined use are novel challenges.

CONCLUSIONS

PPIs display the potential in enhancing the sensitivity of chemoradiotherapy to defend against glioma based on TME. In the clinic, it is also necessary to explore specific concentrations and dosages in synthetic applications.