Simvastatin Improves Outcomes of Endotoxin-induced Coagulopathy by Regulating Intestinal Microenvironment

The causal impact of gut microbiota on circulating adipokine concentrations: a two-sample Mendelian randomization study

PURPOSE

Evidence from previous experimental and observational research demonstrates that the gut microbiota is related to circulating adipokine concentrations. Nevertheless, the debate as to whether gut microbiome composition causally influences circulating adipokine concentrations remains unresolved. This study aimed to take an essential step in elucidating this issue.

METHODS

We used two-sample Mendelian randomization (MR) to causally analyze genetic variation statistics for gut microbiota and four adipokines (including adiponectin, leptin, soluble leptin receptor [sOB-R], and plasminogen activator inhibitor-1 [PAI-1]) from large-scale genome-wide association studies (GWAS) datasets. A range of sensitivity analyses was also conducted to assess the stability and reliability of the results.

RESULTS

The composite results of the MR and sensitivity analyses revealed 22 significant causal associations. In particular, there is a suggestive causality between the family Clostridiaceae1 (IVW: β = 0.063, P = 0.034), the genus Butyrivibrio (IVW: β = 0.029, P = 0.031), and the family Alcaligenaceae (IVW: β=-0.070, P = 0.014) and adiponectin. Stronger causal effects with leptin were found for the genus Enterorhabdus (IVW: β=-0.073, P = 0.038) and the genus Lachnospiraceae (NK4A136 group) (IVW: β=-0.076, P = 0.01). Eight candidate bacterial groups were found to be associated with sOB-R, with the phylum Firmicutes (IVW: β = 0.235, P = 0.03) and the order Clostridiales (IVW: β = 0.267, P = 0.028) being of more interest. In addition, the genus Roseburia (IVW: β = 0.953, P = 0.022) and the order Lactobacillales (IVW: β=-0.806, P = 0.042) were suggestive of an association with PAI-1.

CONCLUSION

This study reveals a causal relationship between the gut microbiota and circulating adipokines and may help to offer novel insights into the prevention of abnormal concentrations of circulating adipokines and obesity-related diseases.

Simvastatin induces human gut bacterial cell surface genes

Drugs intended to target mammalian cells can have broad off-target effects on the human gut microbiota with potential downstream consequences for drug efficacy and side effect profiles. Yet, despite a rich literature on antibiotic resistance, we still know very little about the mechanisms through which commensal bacteria evade non-antibiotic drugs. Here, we focus on statins, one of the most prescribed drug types in the world and an essential tool in the prevention and treatment of high circulating cholesterol levels. Prior work in humans, mice, and cell culture support an off-target effect of statins on human gut bacteria; however, the genetic determinants of statin sensitivity remain unknown. We confirmed that simvastatin inhibits the growth of diverse human gut bacterial strains grown in communities and in pure cultures. Drug sensitivity varied between phyla and was dose-dependent. We selected two representative simvastatin-sensitive species for more in-depth analysis: Eggerthella lenta (phylum: Actinobacteriota) and Bacteroides thetaiotaomicron (phylum: Bacteroidota). Transcriptomics revealed that both bacterial species upregulate genes in response to simvastatin that alter the cell membrane, including fatty acid biogenesis (E. lenta) and drug efflux systems (B. thetaiotaomicron). Transposon mutagenesis identified a key efflux system in B. thetaiotaomicron that enables growth in the presence of statins. Taken together, these results emphasize the importance of the bacterial cell membrane in countering the off-target effects of host-targeted drugs. Continued mechanistic dissection of the various mechanisms through which the human gut microbiota evades drugs will be essential to understand and predict the effects of drug administration in human cohorts and the potential downstream consequences for health and disease.

Association between the use of statins and in-hospital mortality risk in patients with sepsis-induced coagulopathy during ICU stays: a study based on medical information mart for intensive care database

BACKGROUND

The objective of this study was to explore the correlation between statin administration in the intensive care unit (ICU) setting and the in-hospital mortality risk of patients suffering from sepsis-induced coagulopathy (SIC).

METHODS

Utilizing a retrospective cohort study design, this investigation collected data from the Medical Information Mart for Intensive Care (MIMIC)-IV spanning 2008 to 2019. The diagnosis of SIC was established based on a SIC score of 4 or above. Statin usage during the ICU period was extracted from the prescription records based on the keywords of statin medications. The primary endpoint analyzed was the in-hospital mortality within the ICU, characterized by any death occurring during the ICU admission.

RESULTS

During the follow-up, which had a median duration of approximately 7.28 days, 18.19% of the 4,777 SIC patients died in the ICU. Statin was linked with a decrease in the risk of in-hospital mortality for SIC patients in the ICU [hazard ratio (HR): 0.73, 95% confidence interval (CI): 0.60-0.89, P = 0.002]. Relative to rosuvastatin, the use of atorvastatin (HR: 0.54, 95% CI: 0.34-0.85, P = 0.008) or simvastatin (HR: 0.55, 95% CI: 0.33-0.92, P = 0.024), as well as combinations of multiple statins (HR: 0.36, 95% CI: 0.15-0.86, P = 0.022), was associated with a reduction in ICU in-hospital mortality risk. Subgroup analysis also suggested that the use of atorvastatin, simvastatin, or a combination of statins had an advantage over rosuvastatin in reducing ICU in-hospital mortality in SIC patients older than 65 years of age or SIC patients with respiratory failure or cardiogenic shock (all P < 0.05).

CONCLUSION

The present study supports the potential benefits of statin use in mortality in SIC patients during ICU stays. The study encourages clinicians to consider the benefits of statins and supports the ongoing exploration of statins for enhanced outcomes in critical care settings.

Gut barrier dysfunction and endotoxemia in heart failure: A dangerous connubium?

Heart failure (HF) is a leading cause of death worldwide despite recent advances in pharmacological treatments. Gut microbiota dysbiosis and gut barrier dysfunction with consequent bacterial translocation and increased blood endotoxemia has gained much attention as one of the key pathogenetic mechanisms contributing to increased mortality of patients at risk or with cardiovascular disease. Indeed, increased blood levels of lipopolysaccharide (LPS), a glycolipid of outer membrane of gut gram-negative bacteria, have been detected in patients with diabetes, obesity and nonalcoholic fatty liver disease or in patients with established coronary disease such as myocardial infarction or atrial fibrillation, suggesting endotoxemia as aggravating factor via systemic inflammation and eventually vascular damage. Upon interaction with its receptor Toll-like receptor 4 (TLR4) LPS may, in fact, act at different cellular levels so eliciting formation of proinflammatory cytokines or exerting a procoagulant activity. Increasing body of evidence pointed to endotoxemia as factor potentially deteriorating the clinical course of patients with HF, that, in fact, is associated with gut dysbiosis-derived changes of gut barrier functionality and eventually bacteria or bacterial product translocation into systemic circulation. The aim of this review is to summarize current experimental and clinical evidence on the mechanisms linking gut dysbiosis-related endotoxemia with HF, its potential negative impact with HF progression, and the therapeutic strategies that can counteract endotoxemia.

Comparison of the prognostic value of four different critical illness scores in patients with sepsis-induced coagulopathy

In patients with sepsis-induced coagulopathy (SIC), the Chinese DIC scoring system (CDSS) of the Chinese Society of Thrombosis and Hemostasis score, the Japanese Association for Acute Medicine (JAAM) score, the International Society of Thrombosis and Hemostasis (ISTH), and the Can Rapid risk stratification of Unstable angina patients Suppress Adverse outcomes with Early implementation of the ACC/AHA Guidelines (CRUSADE) score were compared for their predictive significance (SIC). From August 2021 through August 2022, 92 SIC patients hospitalized in our hospital's Department of Critical Care Medicine served as study participants. Groups of patients were created with a bad prognosis (n = 35) and a favorable prognosis (n = 57) 14 days following admission. Electronic medical records were used to compile patient information such as demographics (gender, age, and body mass index), medical history (hypertension, diabetes, chronic obstructive pulmonary disease, and chronic kidney disease), treatment (mechanical ventilation, APACHE II score at admission), and outcomes (results). All patients' JAAM, CDSS, ISTH, and CRUSADE scores were recorded. The APACHE II scores of the group with a poor prognosis were noticeably (p < 0.05) higher upon admission than those of the group with a favorable prognosis. The poor prognosis group had higher JAAM, ISTH, CDSS, and CRUSADE scores than the good prognosis group (all p < 0.05). Partial coagulation indicators in fibrinogen, D-dimer, activated partial thromboplastin time, and prothrombin time were positively linked with JAAM, ISTH, CDSS, and CRUSADE (all p < 0.05). At admission, the JAAM, ISTH, CDSS, CRUSADE, and APACHE II scores were independently linked with SIC patients' prognosis (all p < 0.05) in a multivariate logistic regression analysis. According to receiver operating characteristic analysis, the area under the curve for predicting the prognosis of SIC patients using the JAAM, ISTH, CDSS, and CRUSADE4 scores was 0.896, 0.870, 0.852, and 0.737, respectively, with 95% CI being 0.840-0.952, 0.805-0.936, 0.783-0.922 and 0.629-0.845, respectively (all p < 0.05). The prognosis of SIC patients may be predicted in part by their JAAM, ISTH, CDSS, and CRUSADE4 scores, with the CDSS score being the most accurate. This research provides important recommendations for improving the care of patients with SIC.

Statins and Hemostasis: Therapeutic Potential Based on Clinical Evidence

Hemostasis preserves blood fluidity and prevents its loss after vessel injury. The maintenance of blood fluidity requires a delicate balance between pro-coagulant and fibrinolytic status. Endothelial cells (ECs) in the inner face of blood vessels maintain hemostasis through balancing anti-thrombotic and pro-fibrinolytic activities. Dyslipidemias are linked to hemostatic alterations. Thus, it is necessary a better understanding of the underlying mechanisms linking hemostasis with dyslipidemia. Statins are drugs that decrease cholesterol levels in the blood and are the gold standard for treating hyperlipidemias. Statins can be classified into natural and synthetic molecules, approved for the treatment of hypercholesterolemia. The classical mechanism of action of statins is by competitive inhibition of a key enzyme in the synthesis pathway of cholesterol, the HMG-CoA reductase. Statins are frequently administrated by oral ingestion and its interaction with other drugs and food supplements is associated with altered bioavailability. In this review we deeply discuss the actions of statins beyond the control of dyslipidemias, focusing on the actions in thrombotic modulation, vascular and cardiovascular-related diseases, metabolic diseases including metabolic syndrome, diabetes, hyperlipidemia, and hypertension, and chronic diseases such as cancer, chronic obstructive pulmonary disease, and chronic kidney disease. Furthermore, we were prompted to delved deeper in the molecular mechanisms by means statins regulate coagulation acting on liver, platelets, and endothelium. Clinical evidence show that statins are effective regulators of dyslipidemia with a high impact in hemostasis regulation and its deleterious consequences. However, studies are required to elucidate its underlying molecular mechanism and improving their therapeutical actions.