Hemodynamic coherence in sepsis

Intestinal Piezo1 aggravates intestinal barrier dysfunction during sepsis by mediating Ca2+ influx

INTRODUCTION

Intestinal barrier dysfunction is a pivotal factor in sepsis progression. The mechanosensitive ion channel Piezo1 is associated with barrier function; however, its role in sepsis-induced intestinal barrier dysfunction remains poorly understood.

METHODS

The application of cecal ligation and puncture (CLP) modeling was performed on both mice of the wild-type (WT) variety and those with Villin-Piezo1flox/flox genetic makeup to assess the barrier function using in vivo FITC-dextran permeability measurements and immunofluorescence microscopy analysis of tight junctions (TJs) and apoptosis levels. In vitro, Caco-2 monolayers were subjected to TNF-α incubation. Moreover, to modulate Piezo1 activation, GsMTx4 was applied to inhibit Piezo1 activation. The barrier function, intracellular calcium levels, and mitochondrial function were monitored using calcium imaging and immunofluorescence techniques.

RESULTS

In the intestinal tissues of CLP-induced septic mice, Piezo1 protein levels were notably elevated compared with those in normal mice. Piezo1 has been implicated in the sepsis-mediated disruption of TJs, apoptosis of intestinal epithelial cells, elevated intestinal mucosal permeability, and systemic inflammation in WT mice, whereas these effects were absent in Villin-Piezo1flox/flox CLP mice. In Caco-2 cells, TNF-α prompted calcium influx, an effect reversed by GsMTx4 treatment. Elevated calcium concentrations are correlated with increased accumulation of reactive oxygen species, diminished mitochondrial membrane potential, and TJ disruption.

CONCLUSIONS

Thus, Piezo1 is a potential contributor to sepsis-induced intestinal barrier dysfunction, influencing apoptosis and TJ modification through calcium influx-mediated mitochondrial dysfunction.

Influence of Escherichia coli lipopolysaccharide-induced endotoxemia on plasma and tissue disposition of florfenicol after intramuscular administration in rabbits

To assess the effects of the acute inflammatory response (AIR) induced by Escherichia coli lipopolysaccharide (LPS) on plasma and tissue disposition of florfenicol (FFC) and its metabolite florfenicol amine (FFC-a), after its intramuscular (IM) administration, twenty-two New Zealand rabbits were randomly distributed in two experimental groups: Group 1 (LPS) was treated with three intravenous doses of 2 μg LPS/kg bw, before an intramuscular dose of 20 mg/kg FFC twenty-four h after the first LPS or SS injection; Group 2 (Control) was treated with saline solution (SS) in equivalent volumes as LPS-treated group. Blood samples were collected before (T0) and at different times after FFC administration. Acute inflammatory response was assessed in a parallel study where significant increases in body temperature, C-reactive protein concentrations and leukopenia were observed in the group treated with LPS. In another two groups of rabbits, 4 h after FFC treatment, rabbits were euthanized and tissue samples were collected for analysis of FFC and FFC-a concentrations. Pharmacokinetic parameters of FFC that showed significantly higher values in LPS-treated rabbits compared with control rabbits were absorption half-life, area under the curve, mean residence time and clearance /F (Cl/F). Elimination half-life and mean residence time of FFC-a were significantly higher in LPS-treated rabbits, whereas the metabolite ratio of FFC-a decreased significantly. Significant differences in tissue distribution of FFC and FFC-a were observed in rabbits treated with LPS. Modifications in plasma and tissue disposition of FFC and FFC-a were attributed mainly to haemodynamic modifications induced by the AIR through LPS administration.

Prognostic value of APTT combined with fibrinogen and creatinine in predicting 28-Day mortality in patients with septic shock caused by acute enteric perforation

BACKGROUND

Septic shock is one of the leading causes of mortality in intensive care units. This retrospective study was carried out to evaluate the association of clinical available factors with 28-day mortality.

PATIENTS AND METHOD

In this observational study, patients with perioperative septic shocks secondary to intra-abdominal infection caused by enteric perforation were included. A total of 328 sepsis patients were admitted to the surgical intensive care units from January 2012 to December 2016. A total of 138 patients met the enrolment criteria and were included in the study. The data of demographic, clinical and laboratory were all recorded.

RESULT

All these 138 patients received abdominal surgery prior to surgical intensive care units caused by acute enteric perforation. These patients were all met the diagnostic criteria of septic shock according to Sepsis-3. Statistical analysis showed that lactic acid, blood platelet, fibrinogen, creatinine and activated partial thromboplastin time were found to be associated with 28-day mortality. A combination of serum activated partial thromboplastin time combined with fibrinogen and creatinine could predict in-hospital 28-day mortality. The area under the curve of serum activated partial thromboplastin time combined with fibrinogen and creatinine is 0.875 (0.806-0.944).

CONCLUSION

In conclusion, this pilot study demonstrated that these factors can predict the prognosis of septic shock caused by enteric perforation. In order to reduce the mortality, surgeons and intensive care units physician may consider these data in perioperative period.

Combined Multiomics and In Silico Approach Uncovers PRKAR1A as a Putative Therapeutic Target in Multi-Organ Dysfunction Syndrome

Despite all epidemiological, clinical, and experimental research efforts, therapeutic concepts in sepsis and sepsis-induced multi-organ dysfunction syndrome (MODS) remain limited and unsatisfactory. Currently, gene expression data sets are widely utilized to discover new biomarkers and therapeutic targets in diseases. In the present study, we analyzed MODS expression profiles (comprising 13 sepsis and 8 control samples) retrieved from NCBI-GEO and found 359 differentially expressed genes (DEGs), among which 170 were downregulated and 189 were upregulated. Next, we employed the weighted gene co-expression network analysis (WGCNA) to establish a MODS-associated gene co-expression network (weighted) and identified representative module genes having an elevated correlation with age. Based on the results, a turquoise module was picked as our hub module. Further, we constructed the PPI network comprising 35 hub module DEGs. The DEGs involved in the highest-confidence PPI network were utilized for collecting pathway and gene ontology (GO) terms using various libraries. Nucleotide di- and triphosphate biosynthesis and interconversion was the most significant pathway. Also, 3 DEGs within our PPI network were involved in the top 5 significantly enriched ontology terms, with hypercortisolism being the most significant term. PRKAR1A was the overlapping gene between top 5 significant pathways and GO terms, respectively. PRKAR1A was considered as a therapeutic target in MODS, and 2992 ligands were screened for binding with PRKAR1A. Among these ligands, 3 molecules based on CDOCKER score (molecular dynamics simulated-based score, which allows us to rank the binding poses according to their quality and to identify the best pose for each system) and crucial interaction with human PRKAR1A coding protein and protein kinase-cyclic nucleotide binding domains (PKA RI alpha CNB-B domain) via active site binding residues, viz. Val283, Val302, Gln304, Val315, Ile327, Ala336, Ala337, Val339, Tyr373, and Asn374, were considered as lead molecules.

T cell activation profiles can distinguish gram negative/positive bacterial sepsis and are associated with ICU discharge

Introduction

Sepsis is a life-threatening complication resulting from a dysregulated host response to a serious infection, of which bacteria are the most common cause. A rapid differentiation of the gram negative (G^-)/gram positive (G⁺) pathogens facilitates antibiotic treatment, which in turn improves patients' survival.

Methods

We performed a prospective, observational study of adult patients in intensive care unit (ICU) unit and underwent the analysis of peripheral blood lymphocyte subsets, cytokines and other clinical indexes. The enrolled 94 patients were divided into no infection group (n=28) and bacterial sepsis group (n=66), and the latter group was subdivided into G^- (n=46) and G⁺ (n=20) sepsis subgroups.

Results

The best immune biomarker which differentiated the diagnosis of G^- sepsis from G⁺ sepsis, included activation markers of CD69, human leukocyte antigen DR (HLA-DR) on CD3⁺CD8⁺T subset. The ratio of CD3⁺CD4⁺CD69⁺T/CD3⁺CD8⁺CD69⁺T (odds ratio (OR): 0.078(0.012,0.506), P = 0.008), PCT>0.53 ng/ml (OR: 9.31(1.36,63.58), P = 0.023), and CO₂CP<26.5 mmol/l (OR: 10.99(1.29, 93.36), P = 0.028) were predictive of G^- sepsis (versus G⁺ sepsis), and the area under the curve (AUC) was 0.947. Additionally, the ratio of CD3⁺CD4⁺CD69⁺T/CD3⁺CD8⁺CD69⁺T ≤ 0.2697 was an independent risk factor for poor ICU discharge in G^- sepsis patients (HR: 0.34 (0.13, 0.88), P=0.026).

Conclusion

We conclude that enhanced activation of T cells may regulate the excessive inflammatory response of G^- bacterial sepsis, and that T cell activation profiles can rapidly distinguish G^- sepsis from G⁺ sepsis and are associated with ICU discharge.

Predictors of Requirement of Inotrope Among Patients With Early Sepsis: Special Reference to Microcirculatory Parameters

Introduction

The management of septic shock and refractory septic shock is essential in preventing sepsis-related death. The handheld vital microscope is a new modality of investigation for sepsis for microcirculatory assessment. This study aimed to identify predictors of inotrope requirements among patients with early sepsis and impending septic shock with particular reference to sublingual microcirculation assessment parameters.

Methodology

We conducted an observational cross-sectional hospital-based study in central India. The formal sample size was calculated to be 52 patients using a convenient sampling technique. The study was initiated with ethics approval (IHEC-LOP/2019/ MD0090) with consent from the patients. We used the MicroScan (MicroVision Medical, Netherlands) Video Microscope System (No.16A00102) to obtain sidestream dark-field imaging along with the AVA 4.3C software (MicroVision Medical).

Results

Of 51 cases, 60.8% were women, and 39.2% were men, and the study population had a mean age of 41.0 ± 14.9 years. Patients were recruited from medical wards (64.7%) and emergency departments (35.3%). The most common site of infection was gastrointestinal (33.3%), followed by respiratory infections (25.5%) and genitourinary infections (11.8%). The quick sequential organ failure assessment score was 2.0 ± 0.1. Eight patients required inotropes, and six patients died. High respiratory rates and lactate levels were important predictors of inotrope requirements in patients with early sepsis. Sublingual microcirculatory parameters at baseline did not significantly affect the requirement of inotropes consequently.

Conclusions

Sublingual microscopy is a suggested tool for the management of sepsis. However, without clearly defined cut-off values, handheld vital microscopy could not predict fluid responsiveness among patients with early sepsis. Also, it would be difficult to incorporate this technology into regular practice without equipment upgrades and image acquisition software.

The effect of vasoconstriction on intestinal perfusion is determined by preload dependency: A prospective observational study

BACKGROUND

The effects of vasoconstriction on cardiac stroke volume (SV) and indices of peripheral and intestinal perfusion are insufficiently described.

METHODS

In a non-randomized clinical study, 30 patients undergoing elective rectal surgery were exposed to modulation of preload. The primary endpoint was intestinal perfusion (flux), measured by single-point laser Doppler flowmetry. Secondary endpoints were central cardiovascular variables obtained by the LiDCO rapid monitor, the peripheral perfusion index (PPI) derived from the pulse oximetry signal and muscle (StO₂ ) and cerebral oxygenation (ScO₂ ) determined by near-infrared spectroscopy.

RESULTS

For the whole cohort (n = 30), administration of Phenylephrine during HUT induced a median [IQR] increase in SV by 22% [14-41], p = .003 and in mean arterial pressure (MAP) by 54% [31-62], p < .001, with no change in PPI, StO₂ and ScO₂ or flux. In patients who were preload dependent during HUT (stroke volume variation; SSV >10%; n = 23), administration of phenylephrine increased SV by 29% [12-43], p = .01 and MAP by 54% [33-63], p < .001, followed by an increase in intestinal perfusion flux by 60% [15-289], p = .05, while PPI, StO₂ and ScO₂  remained unchanged. For non-preload dependent patients (SSV <10%; n = 7), no changes in hemodynamic indices were seen besides an increase in MAP by 54% [33-58], p = .002.

CONCLUSION

The reflection of vasoconstrictive modulation of preload in systemic cardiovascular variables and indices of perfusion was dependent on preload responsiveness. Administration of phenylephrine to increase preload did not appear to compromise organ perfusion.

The role of peripheral perfusion markers and lactate in septic shock resuscitation

Septic shock leads to progressive hypoperfusion and tissue hypoxia. Unfortunately, numerous uncertainties exist around the best monitoring strategy, as available techniques are mere surrogates for these phenomena. Nevertheless, central venous oxygen saturation (ScvO₂), venous-to-arterial CO₂ gap, and lactate normalization have been fostered as resuscitation targets for septic shock. Moreover, recent evidence has challenged the central role of lactate. Following the ANDROMEDA-SHOCK trial, capillary refill time (CRT) has become a promissory target, considering the observed benefits in mortality, treatment intensity, and organ dysfunction. Interpretation of CRT within a multimodal approach may aid clinicians in guiding resuscitative interventions and stop resuscitation earlier, thus avoiding the risk of morbid fluid overload. Integrative assessment of a patient's perfusion status can be easily performed using bedside clinical tools. Based on its fast kinetics and recent supporting evidence, targeting CRT (within a holistic assessment of perfusion) may improve outcomes in septic shock resuscitation.

Nicotine Improves Survivability, Hypotension, and Impaired Adenosinergic Renal Vasodilations in Endotoxic Rats: Role of α7-nAChRs/HO-1 Pathway

The nicotinic/cholinergic antiinflammatory pathway protects against acute kidney injury and other end-organ damages induced by endotoxemia. In this study, we tested the hypothesis that functional α7-nAChRs/heme oxygenase-1 (HO-1) pathway is imperative for the nicotine counteraction of hemodynamic and renovascular dysfunction caused by acute endotoxemia in rats. Renal vasodilations were induced by cumulative bolus injections of acetylcholine (ACh, 0.01 nmol-7.29 nmol) or ethylcarboxamidoadenosine (NECA, adenosine receptor agonist, 1.6 nmol-100 nmol) in isolated phenylephrine-preconstricted perfused kidneys. The data showed that 6-h treatment with lipopolysaccharide (LPS, 5 mg/kg i.p.) decreased systolic blood pressure and renal vasodilations caused by NECA but not Ach. The endotoxic insult also increased the mortality rate and elevated serum urea and creatinine. These LPS effects were sex-unrelated, except hypotension, and enhanced mortality which were more evident in male rodents, and abrogated after co-administration of nicotine (0.5, 1 mg/kg and 2 mg/kg) in a dose-dependent fashion. The advantageous effects of nicotine on NECA vasodilations, survivability, and kidney biomarkers in endotoxic male rats disappeared upon concurrent exposure to methyllycaconitine citrate (α7-nAChR blocker) or zinc protoporphyrin (HO-1 inhibitor) and were reproduced after treatment with bilirubin, but not hemin (HO-1 inducer) or tricarbonyldichlororuthenium (II) dimer (carbon monoxide-releasing molecule). Together, current biochemical and pharmacological evidence suggests key roles for α7-nAChRs and the bilirubin byproduct of the HO-1 signaling in the nicotine counteraction of renal dysfunction and reduced adenosinergic renal vasodilator capacity in endotoxic rats.

Why Septic Patients Remain Sick After Hospital Discharge?

Sepsis is well known to cause a high patient death rate (up to 50%) during the intensive care unit (ICU) stay. In addition, sepsis survival patients also exhibit a very high death rate after hospital discharge compared to patients with any other disease. The addressed question is then: why septic patients remain ill after hospital discharge? The cellular and molecular mechanisms involved in the high rate of septic patient deaths are still unknown. We described herein the studies that investigated the percentage of septic patients that died after hospital discharge ranging from 90 days up to 5 years. We also reported the symptoms of septic patients after hospital discharge and the development of the recently called post-sepsis syndrome (PSS). The most common symptoms of the PSS are cognitive disabilities, physical functioning decline, difficulties in performing routine daily activities, and poor life quality. The PSS also associates with quite often reinfection and re-hospitalization. This condition is the cause of the high rate of death mentioned above. We reported the proportion of patients dying after hospital discharge up to 5 years of followed up and the PSS symptoms associated. The authors also discuss the possible cellular and metabolic reprogramming mechanisms related with the low survival of septic patients and the occurrence of PSS.

Optimal target in septic shock resuscitation

Septic shock presents a high risk of morbidity and mortality. Through therapeutic strategies, such as fluid administration and vasoactive agents, clinicians intend to rapidly restore tissue perfusion. Nonetheless, these interventions have narrow therapeutic margins. Adequate perfusion monitoring is paramount to avoid progressive hypoperfusion or detrimental over-resuscitation. During early stages of septic shock, macrohemodynamic derangements, such as hypovolemia and decreased cardiac output (CO) tend to predominate. However, during late septic shock, endothelial and coagulation dysfunction induce severe alterations of the microcirculation, making it more difficult to achieve tissue reperfusion. Multiple perfusion variables have been described in the literature, from bedside clinical examination to complex laboratory tests. Moreover, all of them present inherent flaws and limitations. After the ANDROMEDA-SHOCK trial, there is evidence that capillary refill time (CRT) is an interesting resuscitation target, due to its rapid kinetics and correlation with deep hypoperfusion markers. New concepts such as hemodynamic coherence and flow responsiveness may be used at the bedside to select the best treatment strategies at any time-point. A multimodal perfusion monitoring and an integrated analysis with macrohemodynamic parameters is mandatory to optimize the resuscitation of septic shock patients.

Perioperative Quality Initiative (POQI) consensus statement on fundamental concepts in perioperative fluid management: fluid responsiveness and venous capacitance

Background

Optimal fluid therapy in the perioperative and critical care settings depends on understanding the underlying cardiovascular physiology and individualizing assessment of the dynamic patient state.

Methods

The Perioperative Quality Initiative (POQI-5) consensus conference brought together an international team of multidisciplinary experts to survey and evaluate the literature on the physiology of volume responsiveness and perioperative fluid management. The group used a modified Delphi method to develop consensus statements applicable to the physiologically based management of intravenous fluid therapy in the perioperative setting.

Discussion

We discussed the clinical and physiological evidence underlying fluid responsiveness and venous capacitance as relevant factors in fluid management and developed consensus statements with clinical implications for a broad group of clinicians involved in intravenous fluid therapy. Two key concepts emerged as follows: (1) The ultimate goal of fluid therapy and hemodynamic management is to support the conditions that enable normal cellular metabolic function in order to produce optimal patient outcomes, and (2) optimal fluid and hemodynamic management is dependent on an understanding of the relationship between pressure, volume, and flow in a dynamic system which is distensible with variable elastance and capacitance properties.

Effect of Increasing Blood Pressure With Noradrenaline on the Microcirculation of Patients With Septic Shock and Previous Arterial Hypertension

OBJECTIVES

To assess whether an increase in mean arterial pressure in patients with septic shock and previous systemic arterial hypertension changes microcirculatory and systemic hemodynamic variables compared with patients without arterial hypertension (control).

DESIGN

Prospective, nonblinded, interventional study.

SETTING

Three ICUs in two teaching hospitals.

PATIENTS

After informed consent, we included patients older than 18 years with septic shock for at least 6 hours, sedated, and under mechanical ventilation. We paired patients with and without arterial hypertension by age.

INTERVENTIONS

After obtaining systemic and microcirculation baseline hemodynamic variables (time 0), we increased noradrenaline dose to elevate mean arterial pressure up to 85-90 mm Hg before collecting a new set of measurements (time 1).

MEASUREMENTS AND MAIN RESULTS

We included 40 patients (20 in each group). There was no significant difference in age between the groups. After the rise in mean arterial pressure, there was a significant increase in cardiac index and a slight but significant reduction in lactate in both groups. We observed a significant improvement in the proportion of perfused vessels (control: 57.2 ± 14% to 66 ± 14.8%; arterial hypertension: 61.4 ± 12.3% to 70.8 ± 7.1%; groups: p = 0.29; T0 and T1: p < 0.001; group and time interaction: p = 0.85); perfused vessels density (control: 15.6 ± 4 mm/mm to 18.6 ± 4.5 mm/mm; arterial hypertension: 16.4 ± 3.5 mm/mm to 19.1 ± 3 mm/mm; groups: p = 0.51; T0 and T1: p < 0.001; group and time interaction: p = 0.70), and microcirculatory flow index (control: 2.1 ± 0.6 to 2.4 ± 0.6; arterial hypertension: 2.1 ± 0.5 to 2.6 ± 0.2; groups: p = 0.71; T0 and T1: p = 0.002; group and time interaction: p = 0.45) in both groups.

CONCLUSIONS

Increasing mean arterial pressure with noradrenaline in septic shock patients improves density and flow in small vessels of sublingual microcirculation. However, this improvement occurs both in patients with previous arterial hypertension and in those without arterial hypertension.

Challenge to the Intestinal Mucosa During Sepsis

Sepsis is a complex of life-threating organ dysfunction in critically ill patients, with a primary infectious cause or through secondary infection of damaged tissues. The systemic consequences of sepsis have been intensively examined and evidences of local alterations and repercussions in the intestinal mucosal compartment is gradually defining gut-associated changes during sepsis. In the present review, we focus on sepsis-induced dysfunction of the intestinal barrier, consisting of an increased permeability of the epithelial lining, which may facilitate bacterial translocation. We discuss disturbances in intestinal vascular tonus and perfusion and coagulopathies with respect to their proposed underlying molecular mechanisms. The consequences of enzymatic responses by pancreatic proteases, intestinal alkaline phosphatases, and several matrix metalloproteases are also described. We conclude our insight with a discussion on novel therapeutic interventions derived from crucial aspects of the gut mucosal dynamics during sepsis.

Photonic monitoring of treatment during infection and sepsis: development of new detection strategies and potential clinical applications

Despite the strong decline in the infection-associated mortality since the development of the first antibiotics, infectious diseases are still a major cause of death in the world. With the rising number of antibiotic-resistant pathogens, the incidence of deaths caused by infections may increase strongly in the future. Survival rates in sepsis, which occurs when body response to infections becomes uncontrolled, are still very poor if an adequate therapy is not initiated immediately. Therefore, approaches to monitor the treatment efficacy are crucially needed to adapt therapeutic strategies according to the patient's response. An increasing number of photonic technologies are being considered for diagnostic purpose and monitoring of therapeutic response; however many of these strategies have not been introduced into clinical routine, yet. Here, we review photonic strategies to monitor response to treatment in patients with infectious disease, sepsis, and septic shock. We also include some selected approaches for the development of new drugs in animal models as well as new monitoring strategies which might be applicable to evaluate treatment response in humans in the future. Figure Label-free probing of blood properties using photonics.

Microcirculation and red cell transfusion in patients with sepsis

Early identification of sepsis followed by diagnostic blood cultures and prompt administration of appropriate intravenous antibiotics covering all likely pathogen remains the corner stone in the initial management of sepsis. Source control, obtained by harvesting microbiological cultures and removal or drainage of the infected foci, is mandatory. However, optimization of hemodynamically unstable patients including volume support supplemented with vasopressor, inotropic and transfusion of red blood cells (RBCs) in case of persistent hypoperfusion have the potential to reduce morbidity and mortality. Given the imbalance between the ability of the cardiovascular system to deliver enough oxygen to meet the oxygen demand, transfusion of RBCs should theoretically provide the ideal solution to the challenge. However, both changes in the septic patients' RBCs induced by endogenous factors as well as the storage lesion affecting transfused RBCs have negative effects on the microcirculation. RBC morphology, distribution of fatty acids on the membrane surface, RBC deformability needed for capillary circulation and the nitrogen oxide (NO) signaling systems are involved. Although these deteriorating effects develop during storage, transfusion of fresh RBCs has not proven to be beneficial, possibly due to limitations of the studies performed. Until better evidence exists, transfusion guidelines recommend a restrictive strategy of RBC transfusion i.e. transfuse when hemoglobin (Hb)<7g/dL in septic patients.

Platelets and Multi-Organ Failure in Sepsis

Platelets have received increasing attention for their role in the pathophysiology of infectious disease, inflammation, and immunity. In sepsis, a low platelet count is a well-known biomarker for disease severity and more recently authors have focused their attention on the active role of platelets in the pathogenesis of multi-organ failure. Septic shock is characterised by a dysregulated inflammatory response, which can impair the microcirculation and lead to organ injury. Being at the crossroads between the immune system, clotting cascade, and endothelial cells, platelets seem to be an appealing central mediator and possible therapeutic target in sepsis. This review focuses on the pathogenic role of platelets in septic organ dysfunction in humans and animal models.

Beneficial effects of Red Light-Emitting Diode treatment in experimental model of acute lung injury induced by sepsis

Sepsis is a severe disease with a high mortality index and it is responsible for the development of acute lung injury (ALI). We evaluated the effects of light-emitting diode (LED) on ALI induced by sepsis. Balb-c mice were injected with lipopolysaccharide or saline and then irradiated or not with red LED on their tracheas and lungs for 150 s, 2 and 6 h after LPS injections. The parameters were investigated 24 h after the LPS injections. Red LED treatment reduced neutrophil influx and the levels of interleukins 1β, 17 A and, tumor necrosis factor-α; in addition to enhanced levels of interferon γ in the bronchoalveolar fluid. Moreover, red LED treatment enhanced the RNAm levels of IL-10 and IFN-γ. It also partially reduced the elevated oxidative burst and enhanced apoptosis, but it did not alter the translocation of nuclear factor κB, the expression of toll-like receptor 4 (TLR4), as well as, oedema or mucus production in their lung tissues. Together, our data has shown the beneficial effects of short treatment with LED on ALI that are caused by gram negative bacterial infections. It is suggested that LED applications are an inexpensive and non-invasive additional treatment for sepsis.