Thioredoxin a novel biomarker of post-injury sepsis

The Importance of Thioredoxin-1 in Health and Disease

Thioredoxin-1 (Trx-1) is a multifunctional protein ubiquitously found in the human body. Trx-1 plays an important role in various cellular functions such as maintenance of redox homeostasis, proliferation, and DNA synthesis, but also modulation of transcription factors and control of cell death. Thus, Trx-1 is one of the most important proteins for proper cell and organ function. Therefore, modulation of Trx gene expression or modulation of Trx activity by various mechanisms, including post-translational modifications or protein-protein interactions, could cause a transition from the physiological state of cells and organs to various pathologies such as cancer, and neurodegenerative and cardiovascular diseases. In this review, we not only discuss the current knowledge of Trx in health and disease, but also highlight its potential function as a biomarker.

Changing Perspectives from Oxidative Stress to Redox Signaling-Extracellular Redox Control in Translational Medicine

Extensive research has changed the understanding of oxidative stress that has been linked to every major disease. Today we distinguish oxidative eu- and distress, acknowledging that redox modifications are crucial for signal transduction in the form of specific thiol switches. Long underestimated, reactive species and redox proteins of the Thioredoxin (Trx) family are indeed essential for physiological processes. Moreover, extracellular redox proteins, low molecular weight thiols and thiol switches affect signal transduction and cell–cell communication. Here, we highlight the impact of extracellular redox regulation for health, intermediate pathophenotypes and disease. Of note, recent advances allow the analysis of redox changes in body fluids without using invasive and expensive techniques. With this new knowledge in redox biochemistry, translational strategies can lead to innovative new preventive and diagnostic tools and treatments in life sciences and medicine.

Multi-cohort analysis of host immune response identifies conserved protective and detrimental modules associated with severity across viruses

Viral infections induce a conserved host response distinct from bacterial infections. We hypothesized that the conserved response is associated with disease severity and is distinct between patients with different outcomes. To test this, we integrated 4,780 blood transcriptome profiles from patients aged 0 to 90 years infected with one of 16 viruses, including SARS-CoV-2, Ebola, chikungunya, and influenza, across 34 cohorts from 18 countries, and single-cell RNA sequencing profiles of 702,970 immune cells from 289 samples across three cohorts. Severe viral infection was associated with increased hematopoiesis, myelopoiesis, and myeloid-derived suppressor cells. We identified protective and detrimental gene modules that defined distinct trajectories associated with mild versus severe outcomes. The interferon response was decoupled from the protective host response in patients with severe outcomes. These findings were consistent, irrespective of age and virus, and provide insights to accelerate the development of diagnostics and host-directed therapies to improve global pandemic preparedness.

Hydrogen Attenuates Endotoxin-Induced Lung Injury by Activating Thioredoxin 1 and Decreasing Tissue Factor Expression

Endotoxin-induced lung injury is one of the major causes of death induced by endotoxemia, however, few effective therapeutic options exist. Hydrogen inhalation has recently been shown to be an effective treatment for inflammatory lung injury, but the underlying mechanism is unknown. In the current study we aim to investigate how hydrogen attenuates endotoxin-induced lung injury and provide reference values for the clinical application of hydrogen. LPS was used to establish an endotoxin-induced lung injury mouse model. The survival rate and pulmonary pathologic changes were evaluated. THP-1 and HUVECC cells were cultured in vitro. The thioredoxin 1 (Trx1) inhibitor was used to evaluate the anti-inflammatory effects of hydrogen. Hydrogen significantly improved the survival rate of mice, reduced pulmonary edema and hemorrhage, infiltration of neutrophils, and IL-6 secretion. Inhalation of hydrogen decreased tissue factor (TF) expression and MMP-9 activity, while Trx1 expression was increased in the lungs and serum of endotoxemia mice. LPS-stimulated THP-1 and HUVEC-C cells in vitro and showed that hydrogen decreases TF expression and MMP-9 activity, which were abolished by the Trx1 inhibitor, PX12. Hydrogen attenuates endotoxin-induced lung injury by decreasing TF expression and MMP-9 activity via activating Trx1. Targeting Trx1 by hydrogen may be a potential treatment for endotoxin-induced lung injury.

Polygenic Risk Score for Early Prediction of Sepsis Risk in the Polytrauma Screening Cohort

BACKGROUND

Increasing genetic variants associated with sepsis have been identified by candidate-gene and genome-wide association studies, but single variants conferred minimal alterations in risk prediction. Our aim is to evaluate whether a weighted genetic risk score (wGRS) that aggregates information from multiple variants could improve risk discrimination of traumatic sepsis.

METHODS

Sixty-four genetic variants potential relating to sepsis were genotyped in Chinese trauma cohort. Genetic variants with mean decrease accuracy (MDA) > 1.0 by random forest algorithms were selected to construct the multilocus wGRS. The area under the curve (AUC) and net reclassification improvement (NRI) were adopted to evaluate the discriminatory and reclassification ability of weighted genetic risk score (wGRS).

RESULTS

Seventeen variants were extracted to construct the wGRS in 883 trauma patients. The wGRS was significantly associated with sepsis after trauma (OR = 2.19, 95% CI = 1.53-3.15, P = 2.01 × 10-5) after being adjusted by age, sex, and ISS. Patients with higher wGRS have an increasing incidence of traumatic sepsis (P trend = 6.81 × 10-8), higher SOFA (P trend = 5.00 × 10-3), and APACHE II score (P trend = 1.00 × 10-3). The AUC of the risk prediction model incorporating wGRS into the clinical variables was 0.768 (95% CI = 0.739-0.796), with an increase of 3.40% (P = 8.00 × 10-4) vs. clinical factor-only model. Furthermore, the NRI increased 25.18% (95% CI = 17.84-32.51%) (P = 6.00 × 10-5).

CONCLUSION

Our finding indicated that genetic variants could enhance the predictive power of the risk model for sepsis and highlighted the application among trauma patients, suggesting that the sepsis risk assessment model will be a promising screening and prediction tool for the high-risk population.

Urinary proteome analysis of acute hypercoagulable state in rat model induced by ε-aminocaproic acid

The hypercoagulable state occurs in a group of prothrombotic disorders associated with an increased risk for thromboembolic events, but it is difficult to diagnose due to the lack of available biomarkers. This study aimed to investigate systematic changes of urinary proteome in acute hypercoagulable state induced by certain antifibrinolytics. To reduce the effects of both genetic and environmental factors on the urinary proteome, we used a rat model of acute hypercoagulable state induced by an antifibrinolytic agent ε-aminocaproic acid, resembling human hypercoagulable state. Urine samples were collected during acute hypercoagulable state for analysis by liquid chromatography-tandem mass spectrometry (LCMS/MS). Of 65 significantly changed proteins in acute hypercoagulable state, 38 proteins had human orthologs, and 18 proteins were identified as stable in normal human urine. None of the identified proteins have been found to be clotting factors, but 4 proteins are known to be involved in the regulation of blood coagulation factors. Two proteins were verified as the markers associated with acute hypercoagulable state by Western blot analysis. In addition, four common differential urinary proteins have been found in acute hypercoagulable state induced by another antifibrinolytics tranexamic acid. These four proteins are potential biomarkers for early diagnosis of hypercoagulable state to prevent the development of thrombotic diseases.

LBP rs2232618 polymorphism contributes to risk of sepsis after trauma

Background

Previous study revealed that rs2232618 polymorphism (Phe436Leu) within LBP gene is a functional variant and associated with susceptibility of sepsis in traumatic patients. Our aim was to confirm the reported association by enlarging the population sample size and perform a meta-analysis to find additional evidence.

Methods

Traumatic patients from Southwest (n = 1296) and Southeast (n = 445) of China were enrolled in our study. After genotyping, the relationship between rs2232618 and the risk of sepsis was analyzed. Furthermore, we proceeded with a comprehensive literature search and meta-analysis to determine whether the rs2232618 polymorphism conferred susceptibility to sepsis.

Results

Significance correlation was observed between rs2232618 and risk of sepsis in Southwest patients (P = 0.002 for the dominant model, P = 0.006 for the recessive model). The association was confirmed in Southeast cohort (P = 0.005 for the dominant model) and overall combined cohorts (P = 4.5 × 10^-4, P = 0.041 for the dominant and recessive model). Multiple logistical regression analyses suggested that rs2232618 polymorphism was related to higher risk of sepsis (OR = 1.77, 95% CI = 1.26-2.48, P = 0.001 in Southwest patients; OR = 2.11, 95% CI = 1.24-3.58, P = 0.006 in Southeast cohort; OR = 1.54, 95% CI = 1.34-2.08, P = 0.006 in overall cohort). Furthermore, meta-analysis of four studies (including the present study) confirmed that rs2232618 within LBP increased the risk of sepsis (OR = 1.75, P < 0.001 for the dominant model; OR = 6.08, P = 0.003 for the recessive model; OR = 2.72, P < 0.001 for the allelic model).

Conclusions

The results from our replication study and meta-analysis provided firm evidence that rs2232618T allele significantly increased the risk of sepsis.

Anti-Inflammatory Thioredoxin Family Proteins for Medicare, Healthcare and Aging Care

Human thioredoxin (TRX) is a 12-kDa protein with redox-active dithiol in the active site -Cys-Gly-Pro-Cys-, which is induced by biological stress due to oxidative damage, metabolic dysfunction, chemicals, infection/inflammation, irradiation, or hypoxia/ischemia-reperfusion. Our research has demonstrated that exogenous TRX is effective in a wide variety of inflammatory diseases, including viral pneumonia, acute lung injury, gastric injury, and dermatitis, as well as in the prevention and amelioration of food allergies. Preclinical and clinical studies using recombinant TRX (rhTRX) are now underway. We have also identified substances that induce the expression of TRX in the body, in vegetables and other plant ingredients. Skincare products are being developed that take advantage of the anti-inflammatory and anti-allergic action of TRX. Furthermore, we are currently engaged in the highly efficient production of pure rhTRX in several plants, such as lettuce, grain and rice.