Statins decrease mortality in Lebanese patients with sepsis: A multicenter study

Salivary Gland Extract from Aedes aegypti Improves Survival in Murine Polymicrobial Sepsis through Oxidative Mechanisms

Sepsis is a systemic disease with life-threatening potential and is characterized by a dysregulated immune response from the host to an infection. The organic dysfunction in sepsis is associated with the production of inflammatory cascades and oxidative stress. Previous studies showed that Aedes aegypti saliva has anti-inflammatory, immunomodulatory, and antioxidant properties. Considering inflammation and the role of oxidative stress in sepsis, we investigated the effect of pretreatment with salivary gland extract (SGE) from Ae. aegypti in the induction of inflammatory and oxidative processes in a murine cecum ligation and puncture (CLP) model. Here, we evaluated animal survival for 16 days, as well as bacterial load, leukocyte migration, and oxidative parameters. We found that the SGE pretreatment improved the survival of septic mice, reduced bacterial load and neutrophil influx, and increased nitric oxide (NO) production in the peritoneal cavity. With regard to oxidative status, SGE increased antioxidant defenses as measured by Trolox equivalent antioxidant capacity (TEAC) and glutathione (GSH), while reducing levels of the oxidative stress marker malondialdehyde (MDA). Altogether, these data suggest that SGE plays a protective role in septic animals, contributing to oxidative and inflammatory balance during sepsis. Therefore, Ae. aegypti SGE is a potential source for new therapeutic molecule(s) in polymicrobial sepsis, and this effect seems to be mediated by the control of inflammation and oxidative damage.

Prophylactic Treatment With Simvastatin Modulates the Immune Response and Increases Animal Survival Following Lethal Sepsis Infection

Chronic use of statins may have anti-inflammatory action, promoting immunomodulation and survival in patients with sepsis. This study aimed to analyze the effects of pretreatment with simvastatin in lethal sepsis induced by cecal ligation and puncture (CLP). Male Swiss mice received prophylactic treatment with simvastatin or pyrogen-free water orally in a single daily dose for 30 days. After this period, the CLP was performed. Naïve and Sham groups were performed as non-infected controls. Animal survival was monitored for 60 h after the CLP. Half of mice were euthanized after 12 h to analyze colony-forming units (CFUs); hematological parameters; production of IL-10, IL-12, IL-6, TNF-α, IFN-γ, and MCP-1; cell counts on peritoneum, bronchoalveolar lavage (BAL), bone marrow, spleen, and mesenteric lymph node; immunephenotyping of T cells and antigen presenting cells and production of hydrogen peroxide (H₂O₂). Simvastatin induced an increase in survival and a decrease in the CFU count on peritoneum and on BAL cells number, especially lymphocytes. There was an increase in the platelets and lymphocytes number in the Simvastatin group when compared to the CLP group. Simvastatin induced a greater activation and proliferation of CD4+ T cells, as well as an increase in IL-6 and MCP-1 production, in chemotaxis to the peritoneum and in H₂O₂ secretion at this site. These data suggest that simvastatin has an impact on the survival of animals, as well as immunomodulatory effects in sepsis induced by CLP in mice.

Different regulation of Toll-like receptor 4 expression on blood CD14(+) monocytes by simvastatin in patients with sepsis and severe sepsis

We have demonstrated that regulation of Toll-like receptor 4 (TLR4) surface expression levels on blood CD14(+) monocytes by simvastatin treatment in patient with sepsis is different from that in patients with severe sepsis. In patients with sepsis simvastatin treatment statistically significantly decreased TLR4 surface expression level on blood CD14(+) monocytes, while in patients with severe sepsis simvastatin treatment had no significant influence on TLR4 surface expression level on blood CD14(+) monocytes. The changes of plasma interleukin-6 (IL-6) induced by simvastatin in patients with sepsis and severe sepsis were similar with that of TLR4. Our results indicated simvastatin treatment differently influenced inflammation process in patients with sepsis and severe sepsis, which might partially explain the discrepancy, presented by previous trials, about the therapeutic effects of simvastatin treatment in patients with sepsis and severe sepsis.

Impact of statins in outcomes of septic patients: a systematic review

BACKGROUND

The pleiotropic effects of statins have prompted considerable research in fields other than cardiovascular disease. We reviewed the literature aiming to summarize and critically evaluate the current evidence about the potential use of statins in sepsis.

MATERIALS AND METHODS

We searched the Pubmed, SciELO, and Cochrane electronic databases from inception through November 1, 2013, for randomized controlled trials (RCTs) and cohort studies that examined the association between statin use (upon hospital admission or previous users) and the risk or outcome of sepsis. Data on study characteristics, measurement of statin use, and outcomes (adjusted for potential confounders) were extracted. We structured our review according to the Principles of Reporting in Systematic Reviews and Meta-Analysis criteria. Quality assessment of cohort studies was performed using the Ottawa-Newcastle Scale.

RESULTS

Twenty-three cohort studies and 5 RCTs were eligible, comprising 42 549 statin users and 54 201 non-statin users, from 1995 to 2013. The populations included varied from patients admitted to general wards or intensive care units with bacterial infections, community-acquired pneumonia, ventilator-associated pneumonia, bacteremia, or sepsis, to outpatients with chronic kidney disease or established cardiovascular disease. Overall, 16 studies reported a benefit from statin use in morbidity or mortality outcomes (range of adjusted odds ratio, 0.06-0.62; α = 0.05). The remaining 12 studies found no protective effect associated with statin use upon hospital admission or previous users. Among the 5 RCTs, none demonstrated a reduction in mortality.

CONCLUSION

There is insufficient evidence to support the use of statins in patients with sepsis, as the existing studies failed to prove a consistent mortality benefit. More clinical trials are warranted to provide more conclusive knowledge and ultimately change clinical practice.