To What Extent Are the Terminal Stages of Sepsis, Septic Shock, Systemic Inflammatory Response Syndrome, and Multiple Organ Dysfunction Syndrome Actually Driven by a Prion/Amyloid Form of Fibrin?

A Perspective on How Fibrinaloid Microclots and Platelet Pathology May be Applied in Clinical Investigations

Microscopy imaging has enabled us to establish the presence of fibrin(ogen) amyloid (fibrinaloid) microclots in a range of chronic, inflammatory diseases. Microclots may also be induced by a variety of purified substances, often at very low concentrations. These molecules include bacterial inflammagens, serum amyloid A, and the S1 spike protein of severe acute respiratory syndrome coronavirus 2. Here, we explore which of the properties of these microclots might be used to contribute to differential clinical diagnoses and prognoses of the various diseases with which they may be associated. Such properties include distributions in their size and number before and after the addition of exogenous thrombin, their spectral properties, the diameter of the fibers of which they are made, their resistance to proteolysis by various proteases, their cross-seeding ability, and the concentration dependence of their ability to bind small molecules including fluorogenic amyloid stains. Measuring these microclot parameters, together with microscopy imaging itself, along with methodologies like proteomics and imaging flow cytometry, as well as more conventional assays such as those for cytokines, might open up the possibility of a much finer use of these microclot properties in generative methods for a future where personalized medicine will be standard procedures in all clotting pathology disease diagnoses.

Fibrinaloid Microclots and Atrial Fibrillation

Atrial fibrillation (AF) is a comorbidity of a variety of other chronic, inflammatory diseases for which fibrinaloid microclots are a known accompaniment (and in some cases, a cause, with a mechanistic basis). Clots are, of course, a well-known consequence of atrial fibrillation. We here ask the question whether the fibrinaloid microclots seen in plasma or serum may in fact also be a cause of (or contributor to) the development of AF. We consider known 'risk factors' for AF, and in particular, exogenous stimuli such as infection and air pollution by particulates, both of which are known to cause AF. The external accompaniments of both bacterial (lipopolysaccharide and lipoteichoic acids) and viral (SARS-CoV-2 spike protein) infections are known to stimulate fibrinaloid microclots when added in vitro, and fibrinaloid microclots, as with other amyloid proteins, can be cytotoxic, both by inducing hypoxia/reperfusion and by other means. Strokes and thromboembolisms are also common consequences of AF. Consequently, taking a systems approach, we review the considerable evidence in detail, which leads us to suggest that it is likely that microclots may well have an aetiological role in the development of AF. This has significant mechanistic and therapeutic implications.

The critical role of neutrophil-endothelial cell interactions in sepsis: new synergistic approaches employing organ-on-chip, omics, immune cell phenotyping and in silico modeling to identify new therapeutics

Sepsis is a global health concern accounting for more than 1 in 5 deaths worldwide. Sepsis is now defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Sepsis can develop from bacterial (gram negative or gram positive), fungal or viral (such as COVID) infections. However, therapeutics developed in animal models and traditional in vitro sepsis models have had little success in clinical trials, as these models have failed to fully replicate the underlying pathophysiology and heterogeneity of the disease. The current understanding is that the host response to sepsis is highly diverse among patients, and this heterogeneity impacts immune function and response to infection. Phenotyping immune function and classifying sepsis patients into specific endotypes is needed to develop a personalized treatment approach. Neutrophil-endothelium interactions play a critical role in sepsis progression, and increased neutrophil influx and endothelial barrier disruption have important roles in the early course of organ damage. Understanding the mechanism of neutrophil-endothelium interactions and how immune function impacts this interaction can help us better manage the disease and lead to the discovery of new diagnostic and prognosis tools for effective treatments. In this review, we will discuss the latest research exploring how in silico modeling of a synergistic combination of new organ-on-chip models incorporating human cells/tissue, omics analysis and clinical data from sepsis patients will allow us to identify relevant signaling pathways and characterize specific immune phenotypes in patients. Emerging technologies such as machine learning can then be leveraged to identify druggable therapeutic targets and relate them to immune phenotypes and underlying infectious agents. This synergistic approach can lead to the development of new therapeutics and the identification of FDA approved drugs that can be repurposed for the treatment of sepsis.

Ghrelin/GHSR Axis Induced M2 Macrophage and Alleviated Intestinal Barrier Dysfunction in a Sepsis Rat Model by Inactivating E2F1/NF-κB Signaling

Sepsis is an inflammatory reaction disorder state that is induced by infection. The activation and regulation of the immune system play an essential role in the development of sepsis. Our previous studies have shown that ghrelin ameliorates intestinal dysfunction in sepsis. Very little is known about the mechanism of ghrelin and its receptor (GHSR) on the intestinal barrier and the immune function of macrophage regulation. Our research is to investigate the regulatory effect and molecular mechanism of the ghrelin/GHSR axis on intestinal dysfunction and macrophage polarization in septic rats. A rat model of sepsis was established by cecal ligation and puncture (CLP) operation. Then, the sepsis rats were treated with a ghrelin receptor agonist (TZP-101) or ghrelin inhibitor (obestatin). The results suggested that TZP-101 further enhanced ghrelin and GHSR expressions in the colon and spleen of septic rats and obestatin showed the opposite results. Ghrelin/GHSR axis ameliorated colonic structural destruction and intestinal epithelial tight junction injury in septic rats. In addition, the ghrelin/GHSR axis promoted M2-type polarization of macrophages, which was characterized by the decreases of IL-1β, IL-6, and TNF-α, as well as the increase of IL-10. Mechanistically, the ghrelin/GHSR axis promoted E2F2 expression and suppressed the activation of the NF-κB signaling pathway in septic rats. Collectively, targeting ghrelin/GHSR during sepsis may represent a novel therapeutic approach for the treatment of intestinal barrier injury.

A Review of Persistent Post-COVID Syndrome (PPCS)

Persistent post-COVID syndrome, also referred to as long COVID, is a pathologic entity, which involves persistent physical, medical, and cognitive sequelae following COVID-19, including persistent immunosuppression as well as pulmonary, cardiac, and vascular fibrosis. Pathologic fibrosis of organs and vasculature leads to increased mortality and severely worsened quality of life. Inhibiting transforming growth factor beta (TGF-β), an immuno- and a fibrosis modulator, may attenuate these post-COVID sequelae. Current preclinical and clinical efforts are centered on the mechanisms and manifestations of COVID-19 and its presymptomatic and prodromal periods; by comparison, the postdrome, which occurs in the aftermath of COVID-19, which we refer to as persistent post-COVID-syndrome, has received little attention. Potential long-term effects from post-COVID syndrome will assume increasing importance as a surge of treated patients are discharged from the hospital, placing a burden on healthcare systems, patients' families, and society in general to care for these medically devastated COVID-19 survivors. This review explores underlying mechanisms and possible manifestations of persistent post-COVID syndrome, and presents a framework of strategies for the diagnosis and management of patients with suspected or confirmed persistent post-COVID syndrome.

Effects of Albumin Supplements on In-Hospital Mortality in Patients with Sepsis or Septic Shock: A Systemic Review and Meta-Analysis

Objective

To explore the clinical effects of albumin supplements on the basis of crystalloid solution in patients with sepsis or septic shock.

Methods

The online databases including PubMed, Web of Science, Cochrane Library, and EMBASE were comprehensively searched from inception to June 28, 2021, with the keywords including “albumin,” “sepsis,” or “septic shock.” Retrospective cohort (RC) and randomized controlled trials (RCT) were included for analysis. Two authors independently searched and analyzed the literature. The in-hospital mortality at 7 days and 28 days, duration of mechanical ventilation, renal replacement therapy, length of ICU stay, and length of hospital stay were compared between patients with albumin supplements and crystalloid solution and those with crystalloid alone.

Results

A total of 10 studies with 6463 patients were eventually included for meta-analysis. The in-hospital mortality of patients at 7 days (OR = 1.00, 95% CI: 0.81–1.23) and 28 days (OR = 1.02, 95% CI: 0.91–1.13) did not show a significant difference between the two groups of patients. Also, the pooled results demonstrated no significant differences in duration of mechanical ventilation (OR = 0.29, 95% CI: −0.05–0.63), renal replacement therapy (WMD = 1.15, 95% CI: 0.98–1.35), length of ICU stay (WMD = −0.07, 95% CI: −0.62–0.48), and length of hospital stay (WMD = −0.09, 95% CI: −0.70–0.52) between patients receiving albumin plus crystalloid solution and those with crystalloid solution alone.

Conclusion

Albumin supplements on the basis of crystalloid solution did not improve the 7-day and 28-dayin-hospital mortality in patients with sepsis or septic shock compared with those with crystalloid solution alone.

The potential role of ischaemia-reperfusion injury in chronic, relapsing diseases such as rheumatoid arthritis, Long COVID, and ME/CFS: evidence, mechanisms, and therapeutic implications

Ischaemia–reperfusion (I–R) injury, initiated via bursts of reactive oxygen species produced during the reoxygenation phase following hypoxia, is well known in a variety of acute circumstances. We argue here that I–R injury also underpins elements of the pathology of a variety of chronic, inflammatory diseases, including rheumatoid arthritis, ME/CFS and, our chief focus and most proximally, Long COVID. Ischaemia may be initiated via fibrin amyloid microclot blockage of capillaries, for instance as exercise is started; reperfusion is a necessary corollary when it finishes. We rehearse the mechanistic evidence for these occurrences here, in terms of their manifestation as oxidative stress, hyperinflammation, mast cell activation, the production of marker metabolites and related activities. Such microclot-based phenomena can explain both the breathlessness/fatigue and the post-exertional malaise that may be observed in these conditions, as well as many other observables. The recognition of these processes implies, mechanistically, that therapeutic benefit is potentially to be had from antioxidants, from anti-inflammatories, from iron chelators, and via suitable, safe fibrinolytics, and/or anti-clotting agents. We review the considerable existing evidence that is consistent with this, and with the biochemical mechanisms involved.

Burkholderia cepacia Infections at Sites Other than the Respiratory Tract: A Large Case Series from a Tertiary Referral Hospital in Lebanon

Objectives

The Burkholderia cepacia complex (Bcc), which was originally thought to be a single species, represents a group of 24 distinct species that are often resistant to multiple antibiotics, and usually known to cause life-threatening pulmonary infections in cystic fibrosis patients. Herein we describe a series of non-respiratory Bcc infections, the risk factors and epidemiologic factors, in addition to the clinical course.

Patients and methods

This is a retrospective chart review of 44 patients with documented B. cepacia infections isolated from sites other than the respiratory tract admitted between June 2005 and February 2020 to the American University of Beirut Medical Center (AUBMC), a tertiary referral hospital for Lebanon and the Middle East region. The epidemiological background of these patients, their underlying risk factors, the used antibiotic regimens, and the sensitivities of the B. cepacia specimens were collected.

Results

The majority of the Bcc infections (26/44, 59.1%) were hospital-acquired infections. The most common nationality of the patients was Iraqi (18/44, 40.9%), and the most common site of infection was bacteremia (17/44, 38.6%), followed by skin and soft tissues infections (16/44, 36.4%) and vertebral osteomyelitis (8/44, 18.2%). Most of the isolated B. cepacia were susceptible to ceftazidime, carbapenems, followed by TMP-SMX. Patients responded well to therapy with good overall outcome.

Conclusions

Bcc can cause infections outside the respiratory tract, mostly as hospital-acquired infections and in immunocompromised patients. Most patients were referred from countries inflicted by wars raising the possibility of a potential role of conflicts which need to be investigated in future studies. Directed therapy according to susceptibility results proved effective in most patients.

Clinical Characteristics and Death Risk Factors of Severe Sepsis in Children

Sepsis is a systemic inflammatory response syndrome caused by viral infection. The circulatory dysfunction caused by sepsis is also called septic shock or septic shock. The main characteristics are rapid onset, rapid changes, and involvement. Multiple organs in the body make diagnosis difficult, which seriously threatens the survival of patients. As many as one million people worldwide die every year because of SIRS, it is also the leading cause of death among children in hospital ICUs. This article is aimed at studying the clinical characteristics of severe sepsis in children and the risk factors for death. Based on the analysis of the pathogenesis of sepsis and the treatment of septic shock, 65 cases of children with PICU sepsis admitted to a hospital were selected. Data, to study its clinical characteristics and risk factors for death. The results of the study showed that despite the interaction among the removal factors of the three indexes of serum lactic acid value, PCIS level, and the number of organs involved in MODS, they are still related to the mortality of children with severe sepsis.

The Role of Lipopolysaccharide-Induced Cell Signalling in Chronic Inflammation

Lipopolysaccharide (LPS) is the main structural component of the outer membrane of most Gram-negative bacteria and has diverse immunostimulatory and procoagulant effects. Even though LPS is well described for its role in the pathology of sepsis, considerable evidence demonstrates that LPS-induced signalling and immune dysregulation are also relevant in the pathophysiology of many diseases, characteristically where endotoxaemia is less severe. These diseases are typically chronic and progressive in nature and span broad classifications, including neurodegenerative, metabolic, and cardiovascular diseases. This Review reappraises the mechanisms of LPS-induced signalling and emphasises the crucial contribution of LPS to the pathology of multiple chronic diseases, beyond conventional sepsis. This perspective asserts that new ways of approaching chronic diseases by targeting LPS-driven pathways may be of therapeutic benefit in a wide range of chronic inflammatory conditions.

MicroRNA-200b-3p as a biomarker for diagnosis and survival prognosis of multiple organ dysfunction syndrome caused by acute paraquat poisoning

BACKGROUND

Acute paraquat poisoning-induced multiple organ dysfunction syndrome (MODS) leads to the high mortality. This study aimed to investigate the clinical significance of microRNA-200b-3p (miR-200b-3p), an upstream inhibitor of high-mobility group box 1 (HMGB1), in acute paraquat poisoning patients for the prediction of MODS and survival.

METHODS

This study enrolled 80 patients with MODS induced by paraquat and 94 healthy volunteers. The interaction between miR-200b-3p and HMGB1 was identified by luciferase reporter assay. miR-200b-3p levels were measured by quantitative real-time (QRT) PCR. High-mobility group box 1 levels were measured by enzyme-linked immune sorbent assay (ELISA). Receiver operating characteristic analysis was used to evaluate the diagnostic value of miR-200b-3p in screening MODS patients. The relationship between miR-200b-3p and the 28-day survival of MODS patients was evaluated by Kaplan-Meier curves and log-rank test. Cox regression analysis was used to assess the prognostic value of miR-200b-3p. Correlation between miR-200b-3p and HMGB1 was confirmed by Pearson's correlation analysis.

RESULTS

miR-200b-3p directly target HMGB1. miR-200b-3p, decreased in MODS patients, had high diagnostic value to screen MODS patients from healthy controls. Additionally, serum miR-200b-3p was decreased in non-survivors, and patients with low miR-200b-3p level had poor 28-day survival. Serum miR-200b-3p could independently predict the survival prognosis. Moreover, serum HMGB1 level was increased in MODS patients, and was negatively correlated with miR-200b-3p level.

CONCLUSION

Decreased miR-200b-3p may function as a biomarker for the diagnosis and survival prognosis of MODS patients, and miR-200b-3p may be involved in the progression of acute paraquat-induced MODS via regulating inflammatory responses by targeting HMGB1.

TEG®, Microclot and Platelet Mapping for Guiding Early Management of Severe COVID-19 Coagulopathy

An important component of severe COVID-19 disease is virus-induced endothelilitis. This leads to disruption of normal endothelial function, initiating a state of failing normal clotting physiology. Massively increased levels of von Willebrand Factor (VWF) lead to overwhelming platelet activation, as well as activation of the enzymatic (intrinsic) clotting pathway. In addition, there is an impaired fibrinolysis, caused by, amongst others, increased levels of alpha-(2) antiplasmin. The end result is hypercoagulation (proven by thromboelastography^® (TEG^®)) and reduced fibrinolysis, inevitably leading to a difficult-to-overcome hypercoagulated physiological state. Platelets in circulation also plays a significant role in clot formation, but they themselves may also drive hypercoagulation when they are overactivated due to the interactions of their receptors with the endothelium, immune cells or circulating inflammatory molecules. From the literature it is clear that the role of platelets in severely ill COVID-19 patients has been markedly underestimated or even ignored. We here highlight the value of early management of severe COVID-19 coagulopathy as guided by TEG^®, microclot and platelet mapping. We also argue that the failure of clinical trials, where the efficacy of prophylactic versus therapeutic clexane (low molecular weight heparin (LMWH)) were not always successful, which may be because the significant role of platelet activation was not taken into account during the planning of the trial. We conclude that, because of the overwhelming alteration of clotting, the outcome of any trial evaluating an any single anticoagulant, including thrombolytic, would be negative. Here we suggest the use of the degree of platelet dysfunction and presence of microclots in circulation, together with TEG^®, might be used as a guideline for disease severity. A multi-pronged approach, guided by TEG^® and platelet mapping, would be required to maintain normal clotting physiology in severe COVID-19 disease.

Multiple Organ Dysfunction Syndrome Caused by Sepsis: Risk Factor Analysis

Purpose

To analyze the risk factors of multiple organ dysfunction syndromes (MODS) caused by sepsis.

Patients and Methods

A total of 180 patients with sepsis admitted to The First Affiliated Hospital of Harbin Medical University (No. 23, Post Street, Nangang District, Harbin 150001, Heilongjiang province, China) from July 2018 to June 2019 were selected and divided into a non-MODS group and a MODS group, with 90 cases in each group. Clinical data of the patients were retrospectively analyzed, and univariable and multivariable analyses were performed.

Results

The univariable analysis showed that there were no significant differences in terms of age, body temperature, heart rate, respiration, mean arterial pressure, RBC specific volume, blood sodium, serum kalium, and infection site (P > 0.05). Whereas significant differences were found between the groups in terms of gender, arterial blood pH, WBC count, Apache II score, blood glucose, creatinine, chronic medical history, surgery, and ventilator usage (P < 0.05). The growth of bacterial culture, the increase of creatinine level, chronic diseases and Apache II score were discovered to have significant effects on the occurrence of MODS through the multivariable logistic regression analysis.

Conclusion

Bacterial culture, serum creatinine level, history of chronic disease and Apache II score may be risk factors of MODS in sepsis patients.

The effects of early restrictive fluid resuscitation on the clinical outcomes in sepsis patients

OBJECTIVE

To investigate the effects of early restrictive fluid resuscitation (RFR) on the clinical outcomes in sepsis patients.

METHODS

A total of 122 sepsis patients admitted to our hospital were recruited for this study and divided into a study group (the SG, n=56) and a control group (the CG, n=66) according to the treatment method each patient was administered. The SG was administered early RFR, and the CG was administered adequate fluid resuscitation. The clinical data were analyzed retrospectively in both groups. The total infusion volumes, the hemorrhage amounts, the urine outputs, and the Acute Physiology and Chronic Health Evaluation (APACHE II) scores were compared between the two groups. In addition, the heart rates, the mean arterial pressure levels, the central venous pressure levels, and the cardiac function indices were compared between the two groups at 1-7 days after the procedures. The survival and the complication incidence rates were followed up.

RESULTS

The SG showed significantly lower heart rates and mean arterial pressure levels and higher central venous pressure levels than the CG at 1-7 days after the procedures (P<0.05). The cardiac troponin, N-terminal brain pro-natriuretic peptide, and C-reactive protein levels at 3-7 days after the procedures in the SG were significantly lower than the levels in the CG (P<0.05). The cardiac output, stroke volume, and left ventricular ejection fraction scores in the SG were significantly higher than they were in the CG (P<0.05). The survival rate in the SG was significantly higher than it was in the CG at 16, 32, and 64 days after the procedures (P<0.05). The incidence of complications in the SG was lower than it was in the CG (P<0.05).

CONCLUSION

Early RFR can remarkably improve the clinical outcomes, the myocardial injury and survival rates, and the multiple complications incidence rate in sepsis patients.

Study of C-reactive protein, procalcitonin, and immunocyte ratios in 194 patients with sepsis

BACKGROUND

Evidence suggests that C-reactive protein (CRP), procalcitonin (PCT), and immune cells can predict sepsis severity in adult patients. However, the specific values of these indicators are not consistent in predicting prognosis.

METHODS

A retrospective study analyzed the medical records of 194 patients based on the concept of sepsis in 2016 (Sepsis 3.0) from January 2017 to December 2019. A comparative analysis of inflammatory factors associated with patients in the sepsis survival and the non-survival group was performed. The concentrations of CRP and PCT, neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), and platelet-to-lymphocyte ratio (PLR) were measured. ROC curve was used to assess the diagnosis and analysis of the selected indices of sepsis. According to each index's cut-off value of the ROC curve, the patients were divided into two groups, and the prognosis was calculated.

RESULTS

Among the 194 patients, 32 died (16.49%), the median age of the patients was 79 (66.0, 83.3) years, and 118 were male (60.8%). Analysis of related inflammatory indicators showed that CRP, NLR, MLR, PLR, and CRP*PCT in the non-survival group were statistically higher than those in the survival group (all p values were < 0.05). Regression analysis showed that PCT, CRP, NLR, PLR, and CRP*PCT were all independent prognostic factors for patients. The ROC curve results showed that CRP*PCT had the best diagnostic value (AUC = 0.915). The cut-off values of PCT, CRP, NLR, PLR, MLR, and CRP*PCT were 0.25 ng/mL, 85.00 mg/L, 8.66, 275.51, 0.74%, and 5.85 (mg/L)2, respectively. Kaplan-Meier survival estimate showed that patient prognosis between the CRP, PCT, NLR, PLR, and CRP*PCT was statistically different (all values P < 0.05, respectively). However, there was no statistically significant difference in gender and MLR (all values P > 0.05, respectively), grouping based on diagnostic cut-off values.

CONCLUSIONS

In this study, inflammation-related markers PCT, CRP, NLR, MLR, PLR, and CRP*PCT can be used as independent risk factors affecting the prognosis of patients with sepsis. Furthermore, except for MRL, these indicators have cut-off values for predicting patient death.

A protet-based, protonic charge transfer model of energy coupling in oxidative and photosynthetic phosphorylation

Textbooks of biochemistry will explain that the otherwise endergonic reactions of ATP synthesis can be driven by the exergonic reactions of respiratory electron transport, and that these two half-reactions are catalyzed by protein complexes embedded in the same, closed membrane. These views are correct. The textbooks also state that, according to the chemiosmotic coupling hypothesis, a (or the) kinetically and thermodynamically competent intermediate linking the two half-reactions is the electrochemical difference of protons that is in equilibrium with that between the two bulk phases that the coupling membrane serves to separate. This gradient consists of a membrane potential term Δψ and a pH gradient term ΔpH, and is known colloquially as the protonmotive force or pmf. Artificial imposition of a pmf can drive phosphorylation, but only if the pmf exceeds some 150-170mV; to achieve in vivo rates the imposed pmf must reach 200mV. The key question then is 'does the pmf generated by electron transport exceed 200mV, or even 170mV?' The possibly surprising answer, from a great many kinds of experiment and sources of evidence, including direct measurements with microelectrodes, indicates it that it does not. Observable pH changes driven by electron transport are real, and they control various processes; however, compensating ion movements restrict the Δψ component to low values. A protet-based model, that I outline here, can account for all the necessary observations, including all of those inconsistent with chemiosmotic coupling, and provides for a variety of testable hypotheses by which it might be refined.

Prevalence of readily detected amyloid blood clots in 'unclotted' Type 2 Diabetes Mellitus and COVID-19 plasma: a preliminary report

Background

Type 2 Diabetes Mellitus (T2DM) is a well-known comorbidity to COVID-19 and coagulopathies are a common accompaniment to both T2DM and COVID-19. In addition, patients with COVID-19 are known to develop micro-clots within the lungs. The rapid detection of COVID-19 uses genotypic testing for the presence of SARS-Cov-2 virus in nasopharyngeal swabs, but it can have a poor sensitivity. A rapid, host-based physiological test that indicated clotting severity and the extent of clotting pathologies in the individual who was infected or not would be highly desirable.

Methods

Platelet poor plasma (PPP) was collected and frozen. On the day of analysis, PPP samples were thawed and analysed. We show here that microclots can be detected in the native plasma of twenty COVID-19, as well as ten T2DM patients, without the addition of any clotting agent, and in particular that such clots are amyloid in nature as judged by a standard fluorogenic stain. Results were compared to ten healthy age-matched individuals.

Results

In COVID-19 plasma these microclots are significantly increased when compared to the levels in T2DM.

Conclusions

This fluorogenic test may provide a rapid and convenient test with 100% sensitivity (P < 0.0001) and is consistent with the recognition that the early detection and prevention of such clotting can have an important role in therapy.

Erythrocyte, Platelet, Serum Ferritin, and P-Selectin Pathophysiology Implicated in Severe Hypercoagulation and Vascular Complications in COVID-19

Progressive respiratory failure is seen as a major cause of death in severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2)-induced infection. Relatively little is known about the associated morphologic and molecular changes in the circulation of these patients. In particular, platelet and erythrocyte pathology might result in severe vascular issues, and the manifestations may include thrombotic complications. These thrombotic pathologies may be both extrapulmonary and intrapulmonary and may be central to respiratory failure. Previously, we reported the presence of amyloid microclots in the circulation of patients with coronavirus disease 2019 (COVID-19). Here, we investigate the presence of related circulating biomarkers, including C-reactive protein (CRP), serum ferritin, and P-selectin. These biomarkers are well-known to interact with, and cause pathology to, platelets and erythrocytes. We also study the structure of platelets and erythrocytes using fluorescence microscopy (using the markers PAC-1 and CD62PE) and scanning electron microscopy. Thromboelastography and viscometry were also used to study coagulation parameters and plasma viscosity. We conclude that structural pathologies found in platelets and erythrocytes, together with spontaneously formed amyloid microclots, may be central to vascular changes observed during COVID-19 progression, including thrombotic microangiopathy, diffuse intravascular coagulation, and large-vessel thrombosis, as well as ground-glass opacities in the lungs. Consequently, this clinical snapshot of COVID-19 strongly suggests that it is also a true vascular disease and considering it as such should form an essential part of a clinical treatment regime.

Gingipain R1 and Lipopolysaccharide From Porphyromonas gingivalis Have Major Effects on Blood Clot Morphology and Mechanics

Background:Porphyromonas gingivalis and its inflammagens are associated with a number of systemic diseases, such as cardiovascular disease and type 2 diabetes (T2DM). The proteases, gingipains, have also recently been identified in the brains of Alzheimer's disease patients and in the blood of Parkinson's disease patients. Bacterial inflammagens, including lipopolysaccharides (LPSs) and various proteases in circulation, may drive systemic inflammation.

Methods: Here, we investigate the effects of the bacterial products LPS from Escherichia coli and Porphyromonas gingivalis, and also the P. gingivalis gingipain [recombinant P. gingivalis gingipain R1 (RgpA)], on clot architecture and clot formation in whole blood and plasma from healthy individuals, as well as in purified fibrinogen models. Structural analysis of clots was performed using confocal microscopy, scanning electron microscopy, and AFM-Raman imaging. We use thromboelastography® (TEG®) and rheometry to compare the static and dynamic mechanical properties of clots.

Results: We found that these inflammagens may interact with fibrin(ogen) and this interaction causes anomalous blood clotting.

Conclusions: These techniques, in combination, provide insight into the effects of these bacterial products on cardiovascular health, and particularly clot structure and mechanics.

Covid-19: The Rollercoaster of Fibrin(Ogen), D-Dimer, Von Willebrand Factor, P-Selectin and Their Interactions with Endothelial Cells, Platelets and Erythrocytes

Severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2), also known as coronavirus disease 2019 (COVID-19)-induced infection, is strongly associated with various coagulopathies that may result in either bleeding and thrombocytopenia or hypercoagulation and thrombosis. Thrombotic and bleeding or thrombotic pathologies are significant accompaniments to acute respiratory syndrome and lung complications in COVID-19. Thrombotic events and bleeding often occur in subjects with weak constitutions, multiple risk factors and comorbidities. Of particular interest are the various circulating inflammatory coagulation biomarkers involved directly in clotting, with specific focus on fibrin(ogen), D-dimer, P-selectin and von Willebrand Factor (VWF). Central to the activity of these biomarkers are their receptors and signalling pathways on endothelial cells, platelets and erythrocytes. In this review, we discuss vascular implications of COVID-19 and relate this to circulating biomarker, endothelial, erythrocyte and platelet dysfunction. During the progression of the disease, these markers may either be within healthy levels, upregulated or eventually depleted. Most significant is that patients need to be treated early in the disease progression, when high levels of VWF, P-selectin and fibrinogen are present, with normal or slightly increased levels of D-dimer (however, D-dimer levels will rapidly increase as the disease progresses). Progression to VWF and fibrinogen depletion with high D-dimer levels and even higher P-selectin levels, followed by the cytokine storm, will be indicative of a poor prognosis. We conclude by looking at point-of-care devices and methodologies in COVID-19 management and suggest that a personalized medicine approach should be considered in the treatment of patients.

The Biology of Lactoferrin, an Iron-Binding Protein That Can Help Defend Against Viruses and Bacteria

Lactoferrin is a nutrient classically found in mammalian milk. It binds iron and is transferred via a variety of receptors into and between cells, serum, bile, and cerebrospinal fluid. It has important immunological properties, and is both antibacterial and antiviral. In particular, there is evidence that it can bind to at least some of the receptors used by coronaviruses and thereby block their entry. Of importance are Heparan Sulfate Proteoglycans (HSPGs) and the host receptor angiotensin-converting enzyme 2 (ACE2), as based on other activities lactoferrin might prevent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from attaching to the host cells. Lactoferrin (and more specifically enteric-coated LF because of increased bioavailability) may consequently be of preventive and therapeutic value during the present COVID-19 pandemic.

Clinical significance of serum levels of microRNA-27a and its correlation with interleukin-10 in patients with multiple organ dysfunction syndrome caused by acute paraquat poisoning

The aims of the present study were to examine the clinical significance of serum microRNA-27a (miR-27a) levels in patients with multiple organ dysfunction syndrome (MODS) caused by acute paraquat poisoning and to investigate the correlation between miR-27a and interleukin (IL)-10. A total of 82 patients with MODS induced by acute paraquat poisoning and 88 healthy controls were recruited in the present study. Reverse transcription-quantitative PCR was used to measure serum miR-27a expression levels in patients with MODS and the control group. IL-10 serum levels were determined using ELISA. Decreased serum miR-27a level and increased IL-10 expression levels were detected in patients with paraquat poisoning compared with healthy controls (P<0.001). A moderately negative correlation was identified between the serum expression levels of miR-27a and IL-10 (r=-0.5225; P<0.001). miR-27a expression level was found to be associated with blood urea nitrogen, partial pressure of carbon dioxide, arterial blood lactic acid, and the acute physiology and chronic health evaluation II score (APACHE II; P<0.05). The area under the curve for miR-27a was 0.946, with a sensitivity of 86.6% and specificity of 87.5% at a cutoff value of 2.10. The non-survival patient group had lower miR-27a expression levels compared with the survival group (P<0.01). Multivariate Cox regression analyses suggested miR-27a expression level and APACHE II score were independent prognostic factors for 30-day mortality (P<0.01). The present results suggested that serum miR-27a level may be a potential novel diagnostic and prognostic factor for MODS caused by paraquat poisoning. Collectively, miR-27a may be involved in the process of MODS induced by paraquat poisoning by regulating the inflammatory response.

Parkinson's Disease: A Systemic Inflammatory Disease Accompanied by Bacterial Inflammagens

Parkinson’s disease (PD) is a well-known neurodegenerative disease with a strong association established with systemic inflammation. Recently, the role of the gingipain protease group from Porphyromonas gingivalis was implicated in Alzheimer’s disease and here we present evidence, using a fluorescent antibody to detect gingipain R1 (RgpA), of its presence in a PD population. To further elucidate the action of this gingipain, as well as the action of the lipopolysaccharide (LPS) from P. gingivalis, low concentrations of recombinant RgpA and LPS were added to purified fluorescent fibrinogen. We also substantiate previous findings regarding PD by emphasizing the presence of systemic inflammation via multiplex cytokine analysis, and demonstrate hypercoagulation using thromboelastography (TEG), confocal and electron microscopy. Biomarker analysis confirmed significantly increased levels of circulating proinflammatory cytokines. In our PD and control blood analysis, our results show increased hypercoagulation, the presence of amyloid formation in plasma, and profound ultrastructural changes to platelets. Our laboratory analysis of purified fibrinogen with added RgpA, and/or LPS, showed preliminary data with regards to the actions of the protease and the bacterial membrane inflammagen on plasma proteins, to better understand the nature of established PD.

Both lipopolysaccharide and lipoteichoic acids potently induce anomalous fibrin amyloid formation: assessment with novel Amytracker™ stains

In recent work, we discovered that the presence of highly substoichiometric amounts (10⁻⁸ molar ratio) of lipopolysaccharide (LPS) from Gram-negative bacteria caused fibrinogen clotting to lead to the formation of an amyloid form of fibrin. We here show that the broadly equivalent lipoteichoic acids (LTAs) from two species of Gram-positive bacteria have similarly (if not more) potent effects. Using thioflavin T fluorescence to detect amyloid as before, the addition of low concentrations of free ferric ion is found to have similar effects. Luminescent conjugated oligothiophene dyes (LCOs), marketed under the trade name Amytracker™, also stain classical amyloid structures. We here show that they too give very large fluorescence enhancements when clotting is initiated in the presence of the four amyloidogens (LPS, ferric ions and two LTA types). The staining patterns differ significantly as a function of both the amyloidogens and the dyes used to assess them, indicating clearly that the nature of the clots formed is different. This is also the case when clotting is measured viscometrically using thromboelastography. Overall, the data provide further evidence for an important role of bacterial cell wall products in the various coagulopathies that are observable in chronic, inflammatory diseases. The assays may have potential in both diagnostics and therapeutics.

Shengjiang Powder ameliorates myocardial injury in septic rats by downregulating the phosphorylation of P38-MAPK

Sepsis is the systemic inflammatory response caused by infection. Cardiac dysfunction is an acknowledged result of sepsis. Shengjiang Powder, a prescribed traditional Chinese medicine, showed anti-infection and antipyretic functions in our previous study. In this study, we established a septic rat model via cecal ligation puncture (CLP) to evaluate the effects of Shengjiang Powder on sepsis and the involvement of P38 mitogen activated protein kinase (P38-MAPK) signaling. The 10 main ingredients of Shengjiang Powder were identified by LC-MS. The results of this study indicated that Shengjiang Powder at a concentration of 3.0 g/kg with SB203580 (an inhibitor of P38-MAPK) could improve myocardial injury, ameliorate the histopathological abnormalities, decrease apoptosis and upregulate proliferating cell nuclear antigen (PCNA) levels in myocardial tissues. Further, cytokine mRNA expression levels (tumor necrosis factor - alpha, TNF-α and interleukin 6, IL-6) were decreased by Shengjiang Powder and SB203580 in the myocardial tissues. Furthermore, the p-P38 protein level in myocardial tissues was upregulated in septic rats but decreased upon treatment with Shengjiang Powder and SB203580; however, the relative protein level of P38 showed no significant changes. Collectively, Shengjiang Powder showed a myocardial protective effect on rats with CLP-induced sepsis.

Protective Effects of Live Combined B. subtilis and E. faecium in Polymicrobial Sepsis Through Modulating Activation and Transformation of Macrophages and Mast Cells

Aims: Clinical studies showed that the use of probiotics during critical illness reduced nosocomial infection and improved clinical outcome. However, the functional mechanisms of probiotics is remains unclear. Therefore the aim of current study is to explore the protective effects and understand the underlying mechanisms for the beneficial effects of live combined Bacillus subtilis and Enterococcus faecium (LCBE) in cecal ligation puncture (CLP)-induced sepsis.

Methods and Results: Seven-week-old C57BL/6J mice were divided into three groups: sham group (6 mice), CLP-control group (20 mice, pretreatment with saline for 7 days before CLP surgery) and CLP-probiotics group (14 mice, pretreatment with LCBE enteric-coated capsules for 7 days before CLP surgery). In survival experiment, mice were monitored for 7 days after CLP. After the procedure, mice were sacrificed, and, serum, and peritoneal lavage fluid were collected and intestinal ileal samples were harvested.

Results: Our results showed that the mortality was significantly reduced in mice CLP-probiotics group vs. CLP-control group (P < 0.05). Also, treatment CLP-probiotics group decreased the injury scores CLP-probiotics group when compared to CLP-control group. Additionally, levels of pro-inflammatory cytokines IL-6 and TNF-α levels in the serum and intestinal ileal tissues of CLP-probiotics group were reduced when compared to CLP-control group (P < 0.05). However, no significant differences in anti-inflammatory levels of IL-10 and TGF-β1 were observed between CLP-control and CLP-probiotic groups. Furthermore, our experiments showed that that probiotic treatment suppressed the macrophage activation and transformation from M-type to M1-type, inhibited the mast cells (MCs) degranulation, and activation of AKT (kinase B) pathway.

Conclusion: In conclusion, our data shows that probiotics have a protective role in CLP septic mice through reducing intestinal inflammation, altering macrophage polarization and MCs degranulation, and regulating AKT signaling.

Significance and Impact of Study: This study demonstrated the protective effects and mechanisms involved in the protective role of live combined Bacillus subtilis and Enterococcus faecium (LCBE) in CLP-induced septic mice model.

The Potential of LPS-Binding Protein to Reverse Amyloid Formation in Plasma Fibrin of Individuals With Alzheimer-Type Dementia

Many studies indicate that there is a (mainly dormant) microbial component in the progressive development of Alzheimer-type dementias (ADs); and that in the case of Gram-negative organisms, a chief culprit might be the shedding of the highly inflammagenic lipopolysaccharide (LPS) from their cell walls. We have recently shown that a highly sensitive assay for the presence of free LPS [added to platelet poor plasma (PPP)] lies in its ability (in healthy individuals) to induce blood to clot into an amyloid form. This may be observed in a SEM or in a confocal microscope when suitable amyloid stains (such as thioflavin T) are added. This process could be inhibited by human lipopolysaccharide-binding protein (LBP). In the current paper, we show using scanning electron microscopy and confocal microscopy with amyloid markers, that PPP taken from individuals with AD exhibits considerable amyloid structure when clotting is initiated with thrombin but without added LPS. Furthermore, we could show that this amyloid structure may be reversed by the addition of very small amounts of LBP. This provides further evidence for a role of microbes and their inflammagenic cell wall products and that these products may be involved in pathological clotting in individuals with AD.

Lipopolysaccharide-binding protein (LBP) can reverse the amyloid state of fibrin seen or induced in Parkinson's disease

The thrombin-induced polymerisation of fibrinogen to form fibrin is well established as a late stage of blood clotting. It is known that Parkinson's Disease (PD) is accompanied by dysregulation in blood clotting, but it is less widely known as a coagulopathy. In recent work, we showed that the presence of tiny amounts of bacterial lipopolysaccharide (LPS) in healthy individuals could cause clots to adopt an amyloid form, and this could be observed via scanning electron microscopy (SEM) or via the fluorescence of thioflavin-T. This could be prevented by the prior addition of lipopolysaccharide-binding protein (LBP). We had also observed by SEM this unusual clotting in the blood of patients with Parkinson's Disease. We hypothesised, and here show, that this too can be prevented by LBP in the context of PD. This adds further evidence implicating inflammatory microbial cell wall products as an accompaniment to the disease, and may be part of its aetiology. This may lead to novel treatment strategies in PD designed to target microbes and their products.

Immunological Tolerance, Pregnancy, and Preeclampsia: The Roles of Semen Microbes and the Father

Although it is widely considered, in many cases, to involve two separable stages (poor placentation followed by oxidative stress/inflammation), the precise originating causes of preeclampsia (PE) remain elusive. We have previously brought together some of the considerable evidence that a (dormant) microbial component is commonly a significant part of its etiology. However, apart from recognizing, consistent with this view, that the many inflammatory markers of PE are also increased in infection, we had little to say about immunity, whether innate or adaptive. In addition, we focused on the gut, oral and female urinary tract microbiomes as the main sources of the infection. We here marshall further evidence for an infectious component in PE, focusing on the immunological tolerance characteristic of pregnancy, and the well-established fact that increased exposure to the father's semen assists this immunological tolerance. As well as these benefits, however, semen is not sterile, microbial tolerance mechanisms may exist, and we also review the evidence that semen may be responsible for inoculating the developing conceptus (and maybe the placenta) with microbes, not all of which are benign. It is suggested that when they are not, this may be a significant cause of PE. A variety of epidemiological and other evidence is entirely consistent with this, not least correlations between semen infection, infertility and PE. Our view also leads to a series of other, testable predictions. Overall, we argue for a significant paternal role in the development of PE through microbial infection of the mother via insemination.

Substantial fibrin amyloidogenesis in type 2 diabetes assessed using amyloid-selective fluorescent stains

BACKGROUND

We have previously shown that many chronic, inflammatory diseases are accompanied, and possibly partly caused or exacerbated, by various coagulopathies, manifested as anomalous clots in the form of 'dense matted deposits'. More recently, we have shown that these clots can be amyloid in nature, and that the plasma of healthy controls can be induced to form such clots by the addition of tiny amounts of bacterial lipopolysaccharide or lipoteichoic acid. Type 2 diabetes (T2D) is also accompanied by raised levels of LPS.

METHODS

We use superresolution and confocal microscopies to investigate the amyloid nature of clots from healthy and T2D individuals.

RESULTS

We show here, with the established stain thioflavin T and the novel stains Amytracker™ 480 and 680, that the clotting of plasma from type 2 diabetics is also amyloid in nature, and that this may be prevented by the addition of suitable concentrations of LPS-binding protein.

CONCLUSION

This implies strongly that there is indeed a microbial component to the development of type 2 diabetes, and suggests that LBP might be used as treatment for it and its sequelae.

Lipopolysaccharide-binding protein (LBP) reverses the amyloid state of fibrin seen in plasma of type 2 diabetics with cardiovascular co-morbidities

Type 2 diabetes (T2D) has many cardiovascular complications, including a thrombotic propensity. Many such chronic, inflammatory diseases are accompanied (and may be exacerbated, and possibly even largely caused) by amyloid fibril formation. Recognising that there are few strong genetic associations underpinning T2D, but that amyloidogenesis of amylin is closely involved, we have been seeking to understand what might trigger the disease. Serum levels of bacterial lipopolysaccharide are raised in T2D, and we recently showed that fibrin(ogen) polymerisation during blood clotting can be affected strongly by LPS. The selectivity was indicated by the regularisation of clotting by lipopolysaccharide-binding protein (LBP). Since coagulopathies are a hallmark of T2D, we wondered whether they might too be caused by LPS (and reversed by LBP). We show here, using SEM and confocal microscopy, that platelet-poor-plasma from subjects with T2D had a much greater propensity for hypercoagulability and for amyloidogenesis, and that these could both be reversed by LBP. These data imply that coagulopathies are an important feature of T2D, and may be driven by ‘hidden’ LPS. Given the prevalence of amyloid formation in the sequelae of diabetes, this opens up novel strategies for both the prevention and treatment of T2D.

Major involvement of bacterial components in rheumatoid arthritis and its accompanying oxidative stress, systemic inflammation and hypercoagulability

We review the evidence that infectious agents, including those that become dormant within the host, have a major role to play in much of the etiology of rheumatoid arthritis and the inflammation that is its hallmark. This occurs in particular because they can produce cross-reactive (auto-)antigens, as well as potent inflammagens such as lipopolysaccharide that can themselves catalyze further inflammagenesis, including via β-amyloid formation. A series of observables coexist in many chronic, inflammatory diseases as well as rheumatoid arthritis. They include iron dysregulation, hypercoagulability, anomalous morphologies of host erythrocytes, and microparticle formation. Iron dysregulation may be responsible for the periodic regrowth and resuscitation of the dormant bacteria, with concomitant inflammagen production. The present systems biology analysis benefits from the philosophical idea of "coherence," that reflects the principle that if a series of ostensibly unrelated findings are brought together into a self-consistent narrative, that narrative is thereby strengthened. As such, we provide a coherent and testable narrative for the major involvement of (often dormant) bacteria in rheumatoid arthritis.