Inhibition of a Microbiota-derived Peptide Ameliorates Established Acute Lung Injury

One lung ventilation during thoracoscopic lobectomy alters lung microbiome miversity and composition

Current research indicates that the lungs are not sterile and maintain their own unique microecological balance, which can be disrupted by mechanical ventilation.One-lung ventilation (OLV) induces ischemia-reperfusion (IR) injury in the non-ventilated lung, a common contributor to acute lung injury during the perioperative period. This study investigates alterations in the pulmonary microbiome following one-lung ventilation during thoracoscopic lobectomy and evaluates the impact of differential microbiota on inflammatory responses. Approved by the Hospital Ethics Committee, this study involved 65 patients undergoing thoracoscopic lobectomy from April 2024 to June 2024. An internally controlled paired analysis was implemented to compare bronchoalveolar lavage fluid(BALF) collected from the operative side lung before and after one-lung ventilation. Key outcomes included changes in lung microbiota composition, levels of IL-1β and TNF-α, and the incidence of postoperative complications, with samples preserved for future analysis. Our research revealed significant changes in the abundances of Veillonella, Rothia, Ralstonia, and Melittanglum following one-lung ventilation during thoracoscopic lobectomy. However, there were no notable changes in overall microbial diversity, and alpha diversity remained unchanged. Correspondingly, the levels of IL-1β and TNF-α in the bronchoalveolar lavage fluid significantly increased post-OLV, positively correlating with Ralstonia abundance. The operational taxonomic units and species abundances significantly decreased following one-lung ventilation; nevertheless, overall microbial diversity remained stable. In BALF, levels of IL-1β and TNF-α were markedly elevated, with Ralstonia identified as a key pulmonary microbiome agent influencing inflammatory responses after one-lung ventilation.

Assessing the impact of gut microbiota and metabolic products on acute lung injury following intestinal ischemia-reperfusion injury: harmful or helpful?

Ischemia-reperfusion injury (IRI) is a common and clinically significant form of tissue damage encountered in medical practice. This pathological process has been thoroughly investigated across a variety of clinical settings, including, but not limited to, sepsis, organ transplantation, shock, myocardial infarction, cerebral ischemia, and stroke. Intestinal IRI, in particular, is increasingly recognized as a significant clinical entity due to marked changes in the gut microbiota and their metabolic products, often described as the body's "second genome." These changes in intestinal IRI lead to profound alterations in the gut microbiota and their metabolic outputs, impacting not only the pathology of intestinal IRI itself but also influencing the function of other organs through various mechanisms. Notable among these are brain, liver, and kidney injuries, with acute lung injury being especially significant. This review seeks to explore in depth the roles and mechanisms of the gut microbiota and their metabolic products in the progression of acute lung injury initiated by intestinal IRI, aiming to provide a theoretical basis and directions for future research into the treatment of related conditions.

Role of microbiota-derived corisin in coagulation activation during SARS-CoV-2 infection

BACKGROUND

Coagulopathy is a major cause of morbidity and mortality in COVID-19 patients. Hypercoagulability in COVID-19 results in deep vein thrombosis, thromboembolic complications, and diffuse intravascular coagulation. Microbiome dysbiosis influences the clinical course of COVID-19. However, the role of dysbiosis in COVID-19-associated coagulopathy is not fully understood.

OBJECTIVES

The present study tested the hypothesis that the microbiota-derived proapoptotic corisin is involved in the coagulation system activation during SARS-CoV-2 infection.

METHODS

This cross-sectional study included 47 consecutive patients who consulted for symptoms of COVID-19. A mouse acute lung injury model was used to recapitulate the clinical findings. A549 alveolar epithelial, THP-1, and human umbilical vein endothelial cells were used to evaluate procoagulant and anticoagulant activity of corisin.

RESULTS

COVID-19 patients showed significantly high circulating levels of corisin, thrombin-antithrombin complex, D-dimer, tumor necrosis factor-α, and monocyte-chemoattractant protein-1 with reduced levels of free protein S compared with healthy subjects. The levels of thrombin-antithrombin complex, D-dimer, and corisin were significantly correlated. A monoclonal anticorisin-neutralizing antibody significantly inhibited the inflammatory response and coagulation system activation in a SARS-CoV-2 spike protein-associated acute lung injury mouse model, and the levels of corisin and thrombin-antithrombin complex were significantly correlated. In an in vitro experiment, corisin increased the tissue factor activity and decreased the anticoagulant activity of thrombomodulin in epithelial, endothelial, and monocytic cells.

CONCLUSION

The microbiota-derived corisin is significantly increased and correlated with activation of the coagulation system during SARS-CoV-2 infection, and corisin may directly increase the procoagulant activity in epithelial, endothelial, and monocytic cells.

Cell Death in Acute Organ Injury and Fibrosis

Tissue fibrosis is characterized by the excessive accumulation of extracellular matrix in various organs, including the lungs, liver, skin, kidneys, pancreas, and heart, ultimately leading to organ failure [...].

Elevated plasma and bile levels of corisin, a microbiota-derived proapoptotic peptide, in patients with severe acute cholangitis

BACKGROUND

Acute cholangitis is a severe, life-threatening infection of the biliary system that requires early diagnosis and treatment. The Tokyo Guidelines recommend a combination of clinical, laboratory, and imaging findings for diagnosis and severity assessment, but there are still challenges in identifying severe cases that need immediate intervention. The microbiota and its derived products have been implicated in the pathogenesis of acute cholangitis. Corisin is a microbiome-derived peptide that induces cell apoptosis, acute tissue injury, and inflammation. This study aimed to evaluate the potential of plasma and bile corisin as a biomarker of acute cholangitis.

METHODS

Forty patients with acute cholangitis associated with choledocholithiasis or malignant disease were enrolled. Nine patients without acute cholangitis were used as controls. Corisin was measured by enzyme immunoassays in plasma and bile samples. Patients were classified into severe and non-severe groups. The associations of plasma and bile corisin with the clinical grade of acute cholangitis and other parameters were analyzed by univariate and multivariate regression analysis.

RESULTS

Plasma and bile corisin levels were significantly higher in patients with acute cholangitis than in controls. Patients with severe acute cholangitis had significantly higher plasma and bile corisin levels than those with non-severe form of the disease. Bile corisin level was significantly correlated with markers of inflammation, coagulation, fibrinolysis, and renal function. Univariate analysis revealed a significant association of bile corisin but a weak association of plasma corisin with the clinical grade of acute cholangitis. In contrast, multivariate analysis showed a significant relationship between plasma corisin level and the disease clinical grade. The receiver operating characteristic curve analysis showed low sensitivity but high specificity for plasma and bile corisin to detect the severity of acute cholangitis. The plasma and bile corisin sensitivity was increased when serum C-reactive protein level was included in the receiver operating characteristic curve analysis.

CONCLUSIONS

Overall, these findings suggest that plasma and bile corisin levels may be useful biomarkers for diagnosing and monitoring acute cholangitis and that corisin may play a role in the pathophysiology of the disease by modulating inflammatory, coagulation and renal pathways.