The effect of glutathione and N-acetylcysteine on lipoperoxidative damage in patients with early septic shock

Efficacy of dietary supplements on mortality and clinical outcomes in adults with sepsis and septic shock: A systematic review and network meta-analysis

AIM

The aim of this network meta-analysis (NMA) was to investigate the effects of different dietary supplements on the mortality and clinical status of adults with sepsis.

METHODS

We searched PubMed, EMBASE, and the Cochrane Library Central Register of Controlled Trials until February 2023. The inclusion criteria were: 1) randomized controlled trials (RCT)s; 2) adults suffering sepsis or septic shock; 3) evaluation of short- or long-mortality; and 4) publications between 1994 and 2023. The general information of studies and details of interventions were extracted. The primary outcome was short-term mortality (<90 days), and the secondary outcomes were long-term mortality (≥90 days), length of ICU and hospital stays, and duration of mechanical ventilation (MV). The risk of bias of RCTs was assessed using the Cochrane risk of bias tool 2 (ROB2). A random effect NMA was performed to rank the effect of each intervention using a frequentist approach.

RESULTS

Finally, 56 RCTs with 5957 participants met the criteria. Approximately, one-third of RCTs were low risk of bias. NMA analysis revealed that there was no treatment more effective in short- or long-term mortality than control or other interventions, except for magnesium (RR: 0.33, 95% CI: 0.14, 0.79; GRADE = low) and vitamin C (RR: 0.81, 95% CI: 0.67, 0.99; low certainty evidence), which had beneficial effects on short-term mortality. Moreover, eicosapentaenoic acid, gamma-linolenic acid, and antioxidants (EPA + GLA + AOs) combination was the most effective, and magnesium, vitamin D and vitamin C were the other effective approaches in terms of duration of MV, and ICU length of stay. There was no beneficial dietary supplement for hospital stay in these patients.

CONCLUSIONS

In septic patients, none of the dietary supplements had a substantial effect on mortality except for magnesium and vitamin C, which were linked to lower short-term mortality with low certainty of evidence. Further investigation into high-quality studies with the use of dietary supplements for sepsis should be highly discouraged.

Evaluation of efficacy and safety of vitiligo treatment with micro-needling combined with N-Acetylcysteine and micro-needling alone: A double-blinded randomized controlled clinical trial

INTRODUCTION

Vitiligo is a skin pigmentation disorder caused by the selective degradation of melanocytes. This study investigates the therapeutic effects of microneedling with and without N-acetylcysteine (NAC) in patients with persistent and limited vitiligo.

METHOD

This research employed a clinical trial design with double-blind randomization. Individuals affected by vitiligo and seeking treatment at Rasool Akram Medical Complex were divided into two separate treatment groups. In the intervention group, 24 affected areas underwent meso-microneedling using 5% NAC ampoules over six sessions, in addition to the application of 4.7% NAC cream once daily on the specified area. Conversely, the control group, consisting of 22 lesions, underwent microneedling using distilled water during six sessions. The severity of lesions and the extent of repigmentation were gauged using the Modified VETI Score. Assessment of treatment efficacy was determined through both physician evaluations and patient feedback.

RESULTS

Twenty patients with a mean age of 36.4 years were recruited. The mean percentage of lesions and their intensity were significantly improved 2 weeks after the third session and 1 month after the end of the treatment (p < 0.01). There was no statistically significant difference between the intervention and control groups. Gender, age, family history, duration of disease, duration of disease stability, and history of hypothyroidism had no statistically significant relationship with patients' treatment outcomes (p > 0.05).

CONCLUSION

Microneedling with or without the application of NAC appears to be an effective treatment option for persistent vitiligo lesions. However, despite the higher improvement rate with the application of NAC, the difference was not significant.

Unraveling the Multifaceted Role of Glutathione in Sepsis: A Comprehensive Review

Sepsis remains a formidable challenge in healthcare, characterized by a dysregulated host response to infection, leading to organ dysfunction and high mortality rates. Glutathione, a critical antioxidant and regulator of cellular redox balance, has emerged as a key player in the pathophysiology of sepsis. This comprehensive review explores the multifaceted role of glutathione in sepsis, focusing on its involvement in oxidative stress, immune modulation, and organ dysfunction. Glutathione depletion exacerbates oxidative damage and inflammatory responses, thereby contributing to the progression of sepsis. Understanding the intricate mechanisms underlying glutathione dysregulation in sepsis offers potential therapeutic avenues, with strategies targeting glutathione pathways showing promise in mitigating septic complications. However, further research is needed to optimize therapeutic approaches and identify biomarkers for patient stratification. Overall, this review underscores the importance of elucidating glutathione's role in sepsis management to improve clinical outcomes and reduce the global burden of this life-threatening condition.

The Combination of Estradiol and N-Acetylcysteine Reduces Ischemia-Reperfusion Injuries of Mice Autografted Ovarian Tissue

Ischemia-reperfusion injuries are important issues after ovarian tissue transplantation (OTT). Our study examined the effects of N-acetylcysteine (NAC) and estradiol (E2) on mouse ovarian autografts. Mice (6-8 weeks) were divided into ovarian autograft as follows: Control: fresh OTT; Sham: cryopreserved/warmed OTT; NAC: cryopreserved/warmed OTT with NAC treatment; E2: cryopreserved/warmed OTT with E2 treatment; NAC+E2: cryopreserved/warmed OTT with the treatment of NAC and E2. In all groups, grafts were harvested on days 2, 7, and 28 after transplantation to evaluate histological parameters, inflammation relative to genes expression, and oxidative status. Histological analysis showed that NAC, E2, and a combination of NAC+E2 significantly increased the primordial, preantral, and antral follicular number. When NAC was used, it significantly reduced the expression of Tnf-α and Fgf-2, whereas it increased Il-1β, Il-6, and Vegf expression levels. The levels of Il-6, Fgf-2, and VEGF were dramatically increased in the E2-treated group. The combination of NAC and E2 significantly increased levels of Il-1β, Il-6, Fgf-2, and Vegf. NAC and E2 alone or in combination significantly increased total antioxidant capacity but did not affect the superoxide dismutase and glutathione peroxidase activities. In conclusion, after transplantation, NAC and E2 alone or in combination, could improve follicular development and angiogenesis as well as decline inflammation and ovarian oxidative damage.

Effects of pulsed electromagnetic fields and N-acetylcysteine on transplantation of vitrified mouse ovarian tissue

In this experimental study, adult female NMRI mice were randomly assigned to five groups: control ;(fresh ovarian transplantation, OT); sham ;(vitrified OT); NAC ;(vitrified OT treated with N-acetyl cysteine, NAC); EMF ;(vitrified OT treated with pulsed electromagnetic fields, PEMF); and NAC+EMF ;(vitrified OT combined with NAC and PEMF). We conducted histological assessments to evaluate follicle reservation and vascularization. Furthermore, we examined the relative expression of Fgf-2, Vegf, Tnf-α, Il-6, Il-1, and Cd31 genes on days 2 and 7 after OT. Additionally, we measured total antioxidant capacity (TAC), malondialdehyde (MDA) levels, as well as the activity of superoxide dismutase (SOD) and glutathione peroxidase (GPX). Our results demonstrated that NAC, PEMF, and NAC+PEMF treatments significantly increased the number of follicles. Moreover, we observed a more pronounced development of vascularization in the NAC, PEMF, and PEMF+NAC groups. The relative expression levels of Fgf-2, Vegf, Tnf-α, Il-1β, and Il-6 were significantly elevated in the NAC, PEMF, and NAC+PEMF groups. Notably, TAC levels decreased significantly in the NAC group compared to the control group. Additionally, the MDA level showed a significant decrease in the PEMF+NAC group when compared to the other groups. Overall, the combination of NAC and PEMF exhibited a synergistic effect in promoting angiogenesis and protecting against oxidative stress and inflammation during OT.

Neutrophil, neutrophil extracellular traps and endothelial cell dysfunction in sepsis

Sepsis is a persistent systemic inflammatory condition involving multiple organ failures resulting from a dysregulated immune response to infection, and one of the hallmarks of sepsis is endothelial dysfunction. During its progression, neutrophils are the first line of innate immune defence against infection. Aside from traditional mechanisms, such as phagocytosis or the release of inflammatory cytokines, reactive oxygen species and other antibacterial substances, activated neutrophils also release web-like structures composed of tangled decondensed DNA, histone, myeloperoxidase and other granules called neutrophil extracellular traps (NETs), which can efficiently ensnare bacteria in the circulation. In contrast, excessive neutrophil activation and NET release may induce endothelial cells to shift toward a pro-inflammatory and pro-coagulant phenotype. Furthermore, neutrophils and NETs can degrade glycocalyx on the endothelial cell surface and increase endothelium permeability. Consequently, the endothelial barrier collapses, contributing to impaired microcirculatory blood flow, tissue hypoperfusion and life-threatening organ failure in the late phase of sepsis.

Effects of oral N-acetyl cysteine on pain and plasma biochemical parameters in fibrocystic breast disorder: A randomized controlled trial

Background

Fibrocystic change is the most common benign lesion in breasts of a woman in her reproductive age. It is an outcome of estrogen excess due to sex hormone imbalance. Cyclical pain as the most common symptom worsens life quality, compels patient to seek health care support continuously, and imposes large amounts of expense to both patient and health system. Current study aims to evaluate effects of N-acetyl cysteine on decreasing pain and changes in plasma biochemistry.

Method

A total of 64 eligible women participated in this double-blinded randomized controlled trial. They were between 18 and 40 years. Participants were randomly allocated into oral N-acetyl cysteine and placebo receivers. Intervention and follow-up lasted for, respectively, a 12-week drugs-on and 12-month drugs-off period. Visual analog scaling was applied to measure severity of pain. Peripheral venous plasma was extracted and compared for inflammatory parameters including high-sensitivity C-reactive protein, total antioxidant capacity, malondialdehyde, total plasma glutathione, lipid profile, and fasting blood sugar.

Results

Oral N-acetyl cysteine significantly decreased feeling of cyclical mastalgia (P < .01) after 12 weeks of consumption. In addition to lowering of plasma level of high-sensitivity C-reactive protein (P = .008), total plasma glutathione significantly increased (P = .02) among N-acetyl cysteine receivers. No change in lipid profile and insulin sensitivity was seen.

Conclusion

N-Acetyl cysteine could mitigate cyclical mastalgia. Inflammation as a considered reason for cyclical mastalgia also was halted by N-acetyl cysteine consumption.

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Daily oral N-acetyl cysteine effectively improves breast pain in FCC.

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NAC breaks inflammatory pathways associated with cyclical mastalgia.

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HDL-cholesterol and total plasma glutathione could be amended following NAC consumption.

The Interplay of Oxidative Stress and ROS Scavenging: Antioxidants as a Therapeutic Potential in Sepsis

Oxidative stress resulting from the disproportion of oxidants and antioxidants contributes to both physiological and pathological conditions in sepsis. To combat this, the antioxidant defense system comes into the picture, which contributes to limiting the amount of reactive oxygen species (ROS) leading to the reduction of oxidative stress. However, a strong relationship has been found between scavengers of ROS and antioxidants in preclinical in vitro and in vivo models. ROS is widely believed to cause human pathology most specifically in sepsis, where a small increase in ROS levels activates signaling pathways to initiate biological processes. An inclusive understanding of the effects of ROS scavenging in cellular antioxidant signaling is essentially lacking in sepsis. This review compiles the mechanisms of ROS scavenging as well as oxidative damage in sepsis, as well as antioxidants as a potent therapeutic. Direct interaction between ROS and cellular pathways greatly affects sepsis, but such interaction does not provide the explanation behind diverse biological outcomes. Animal models of sepsis and a number of clinical trials with septic patients exploring the efficiency of antioxidants in sepsis are reviewed. In line with this, both enzymatic and non-enzymatic antioxidants were effective, and results from recent studies are promising. The usage of these potent antioxidants in sepsis patients would greatly impact the field of medicine.

Plasma Free Thiol Levels during Early Sepsis Predict Future Renal Function Decline

Sepsis is a life-threatening syndrome characterized by acute organ dysfunction due to infection. In particular, acute kidney injury (AKI) is common among patients with sepsis and is associated with increased mortality and morbidity. Oxidative stress is an important contributor to the pathogenesis of sepsis-related AKI. Plasma free thiols (R-SH) reflect systemic oxidative stress since they are readily oxidized by reactive species and thereby serve as antioxidants. Here, we aimed to assess the concentrations of serum free thiols in sepsis and associate these with major adverse kidney events (MAKE). Adult non-trauma patients who presented at the emergency department (ED) with a suspected infection were included. Free thiol levels and ischemia-modified albumin (IMA), a marker of oxidative stress, were measured in plasma at baseline, at the ward, and at three months, and one year after hospitalization. Plasma free thiol levels were lower at the ED visit and at the ward as compared to three months and one year after hospital admission (p < 0.01). On the contrary, plasma levels of IMA were higher at the ED and at the ward compared to three months and one year after hospital admission (p < 0.01). Furthermore, univariate logistic regression analyses showed that plasma free thiol levels at the ED were inversely associated with long-term renal function decline and survival at 90 days (MAKE90) and 365 days (MAKE365) (OR 0.43 per standard deviation [SD] [0.22−0.82, 95% CI], p = 0.011 and OR 0.58 per SD [0.34−0.96, 95% CI], p = 0.035, respectively). A multivariate regression analysis revealed an independent association of plasma free thiols at the ED (OR 0.52 per SD [0.29−0.93, 95% CI], p = 0.028) with MAKE365, even after adjustments for age, eGFR at the ED, SOFA score, and cardiovascular disease. These data indicate the clear role of oxidative stress in the pathogenesis of sepsis-AKI, as reflected in the lower plasma free thiol levels and increased levels of IMA.

Clotting Dysfunction in Sepsis: A Role for ROS and Potential for Therapeutic Intervention

Sepsis is regarded as one of the main causes of death among the critically ill. Pathogen infection results in a host-mediated pro-inflammatory response to fight infection; as part of this response, significant endogenous reactive oxygen (ROS) and nitrogen species (RNS) production occurs, instigated by a variety of sources, including activated inflammatory cells, such as neutrophils, platelets, and cells from the vascular endothelium. Inflammation can become an inappropriate self-sustaining and expansive process, resulting in sepsis. Patients with sepsis often exhibit loss of aspects of normal vascular homeostatic control, resulting in abnormal coagulation events and the development of disseminated intravascular coagulation. Diagnosis and treatment of sepsis remain a significant challenge for healthcare providers globally. Targeting the drivers of excessive oxidative/nitrosative stress using antioxidant treatments might be a therapeutic option. This review focuses on the association between excessive oxidative/nitrosative stress, a common feature in sepsis, and loss of homeostatic control at the level of the vasculature. The literature relating to potential antioxidants is also described.

Oxidative Stress and Endothelial Dysfunction in Sepsis and Acute Inflammation

Significance: Under homeostatic conditions, the endothelium dynamically regulates vascular barrier function, coagulation pathways, leukocyte adhesion, and vasomotor tone. During sepsis and acute inflammation, endothelial cells (ECs) undergo multiple phenotypic and functional modifications that are initially adaptive but eventually become harmful, leading to microvascular dysfunction and multiorgan failure. Critical Issues and Recent Advances: Sepsis unbalances the redox homeostasis toward a pro-oxidant state, characterized by an excess production of reactive oxygen species and reactive nitrogen species, mitochondrial dysfunction, and a breakdown of antioxidant systems. In return, oxidative stress (OS) alters multiple EC functions and promotes a proinflammatory, procoagulant, and proadhesive phenotype. The OS also induces glycocalyx deterioration, cell death, increased permeability, and impaired vasoreactivity. Thus, during sepsis, the ECs are both a significant source and one of the main targets of OS. Future Directions: This review aims at covering the current understanding of the role of OS in the endothelial adaptive or maladaptive multifaceted response to sepsis and to outline the therapeutic potential and issues of targeting OS and endothelial dysfunction during sepsis and septic shock. One of the many challenges in the management of sepsis is now based on the detection and correction of these anomalies of endothelial function.

Reactive Oxygen Species Interact With NLRP3 Inflammasomes and Are Involved in the Inflammation of Sepsis: From Mechanism to Treatment of Progression

Over the past 10 years, the crisis of sepsis has remained a great challenge. According to data from 2016, the sepsis-related mortality rate remains high. In addition, sepsis consumes extensive medical resources in intensive care units, and anti-inflammatory agents fail to improve sepsis-associated hyperinflammation and symptoms of immunosuppression. The specific immune mechanism of sepsis remains to be elucidated. Reactive oxygen species (ROS) are triggered by energy metabolism and respiratory dysfunction in sepsis, which not only cause oxidative damage to tissues and organelles, but also directly and indirectly promote NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome activation. NLRP3 inflammasomes enlarge the inflammatory response and trigger apoptosis of immune cells to exacerbate sepsis progression. Inhibiting the negative effects of ROS and NLRP3 inflammasomes therefore provides the possibility of reversing the excessive inflammation during sepsis. In this review, we describe the interaction of ROS and NLRP3 inflammasomes during sepsis, provide prevention strategies, and identify fields that need further study.

Intensive Care Unit-Acquired Weakness: A Review of Recent Progress With a Look Toward the Future

Intensive care unit-acquired weakness (ICU-AW), a common neuromuscular complication associated with patients in the ICU, is a type of skeletal muscle dysfunction that commonly occurs following sepsis, mobility restriction, hyperglycemia, and the use of glucocorticoids or neuromuscular blocking agents. ICU-AW can lead to delayed withdrawal of mechanical ventilation and extended hospitalization. Patients often have poor prognosis, limited mobility, and severely affected quality of life. Currently, its pathogenesis is uncertain, with unavailability of specific drugs or targeted therapies. ICU-AW has gained attention in recent years. This manuscript reviews the current research status of the epidemiology, pathogenesis, diagnosis, and treatment methods for ICU-AW and speculates the novel perspectives for future research.

Effects of N-Acetylcysteine and N-Acetylcysteine Amide on Erythrocyte Deformability and Oxidative Stress in a Rat Model of Lower Extremity Ischemia-Reperfusion Injury

N-acetylcysteine (NAC) is an antioxidant which works as a free radical scavenger and antiapoptotic agent. N-acetylcysteine-amide (NACA) is a modified form of NAC containing an amide group instead of a carboxyl group of NAC. Our study aims to investigate the effectiveness of these two substances on erythrocyte deformability and oxidative stress in muscle tissue. Materials and Methods. A total of 24 Wistar albino rats were used in our study. The animals were randomly divided into five groups as control (n: 6), ischemia (n: 6), NAC (n: 6), and NACA (n: 6). In the ischemia, NAC, and NACA groups, 120 min of ischemia and 120 min of reperfusion were achieved by placing nontraumatic vascular clamps across the abdominal aorta. The NAC and NACA groups were administered an injection 30 min before ischemia (100 mg/kg NAC; 100 mg/kg NACA; intravenous). Blood samples were taken from the animals at the end of the ischemic period. The lower extremity gastrocnemius muscle was isolated and stored at −80 degrees to assess the total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) values and was analyzed. Results. The erythrocyte deformability index was found to be statistically significantly lower in rats treated with NAC and NACA before ischemia-reperfusion compared to the groups that received only ischemia-reperfusion. In addition, no statistically significant difference was found between the control group and the NAC and NACA groups. The groups receiving NAC and NACA before ischemia exhibited higher total antioxidative status and lower total oxidative status while the oxidative stress index was also lower. Conclusion. The results of our study demonstrated the protective effects of NAC and NACA on erythrocyte deformability and oxidative damage in skeletal muscle in lower extremity ischemia-reperfusion. NAC and NACA exhibited similar protective effects on oxidative damage and erythrocyte deformability.

The effects of chrysin on lipopolysaccharide-induced sepsis in rats

Chrysin (CR) is a flavone found in propolis and many plants. Lipopolysaccharide (LPS) is a component of the cell wall of gram-negative bacteria that causes sepsis. The purpose of this study was to investigate the effects of CR on LPS-induced sepsis in rats. LPS intraperitoneal and a single dose and CR were given orally for 10 days. Rats were sacrificed, blood samples were taken, liver, lung, and kidney tissues were dissected, homogenized, and histopathological analysis was carried out. When CR groups compared to sepsis group, CR significantly decreased the serum levels of aspartate transaminase (AST) and alanine aminotransferase (ALT), interleukin-1 beta (IL-1β), interleukin-10 (IL-10), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and levels of malondialdehyde (MDA) in tissues. CR also increased the levels of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in tissues. Histopathological findings were consistent with biochemical findings. Conclusion, CR could reduce the oxidative stress markers and cytokines in sepsis. PRACTICAL APPLICATIONS: Our approach is to determine the antioxidant and anti-inflammatory effects of chrysin, known as a flavolonoid, which are found in many plants and foods such as honey and propolis. In this study, experimental sepsis model was created using LPS. According to the results of the study, CR can attribute to the ameliorating of oxidative damage in tissues (lung, liver, and kidney) and it can suppress the sepsis-associated acute tissue injury via reduction of inflammation in rats. Even, CR can be used as a pharmacological agent in inflammatory diseases caused by other sources and in many cases causing oxidation.

Metabolic Resuscitation Strategies to Prevent Organ Dysfunction in Sepsis

Significance: Sepsis is the main cause of death among patients admitted to the intensive care unit. As current treatment is limited to antimicrobial therapy and supportive care, mortality remains high, which warrants efforts to find novel therapies. Recent Advances: Mitochondrial dysfunction is emerging as a key process in the induction of organ dysfunction during sepsis, and metabolic resuscitation might reveal to be a novel cornerstone in the treatment of sepsis. Critical Issues: Here, we review novel strategies to maintain organ function in sepsis by precluding mitochondrial dysfunction by lowering energetic demand to allow preservation of adenosine triphosphate-levels, while reducing free radical generation. As the most common strategy to suppress metabolism, that is, cooling, does not reveal unequivocal beneficial effects and may even increase mortality, caloric restriction or modulation of energy-sensing pathways (i.e., sirtuins and AMP-activated protein kinase) may offer safe alternatives. Similar effects may be offered when mimicking hibernation by hydrogen sulfide (H₂S). In addition H₂S may also confer beneficial effects through upregulation of antioxidant mechanisms, similar to the other gasotransmitters nitric oxide and carbon monoxide, which display antioxidant and anti-inflammatory effects in sepsis. In addition, oxidative stress may be averted by systemic or mitochondria-targeted antioxidants, of which a wide range are able to lower inflammation, as well as reduce organ dysfunction and mortality from sepsis. Future Directions: Mitochondrial dysfunction plays a key role in the pathophysiology of sepsis. As a consequence, metabolic resuscitation might reveal to be a novel cornerstone in the treatment of sepsis.

Antioxidant supplementation during illness in dogs: effect on oxidative stress and outcome, an exploratory study

OBJECTIVES

To assess whether combination antioxidant supplementation for 30 days in systemically ill dogs alters antioxidant status, degree of lipid peroxidation, clinical score and survival.

MATERIALS AND METHODS

Forty client-owned systemically-ill hospitalised dogs were eligible for inclusion. Dogs were randomised to no supplementation (NS; n=19) or supplementation with N-acetylcysteine/S-adenosylmethionine/silybin and vitamin E (AS; n=20) for 30 days. Clinical score and oxidative biomarkers including glutathione, cysteine, vitamin E, selenium and urine isoprostanes/creatinine (F₂ -IsoPs/Cr) were determined on days 0 and 30. Glutathione, cysteine, vitamin E and urine F₂ -IsoPs/Cr were quantified by high-performance liquid chromatography, and selenium concentrations determined using atomic absorption spectroscopy.

RESULTS

Thirty-two dogs completed the study (NS, n=16; AS, n=16). Vitamin E concentrations were significantly greater in the supplemented compared to the non-supplemented group. No other markers of oxidative stress significantly changed with supplementation. There was no difference in Day 30 clinical scores or survival between the two groups.

CLINICAL SIGNIFICANCE

In this population of systemically-ill hospitalised dogs, combination antioxidant supplementation did not alter redox state or clinical outcome.

Clinical Trial Assessment of Intermittent and Continuous Infusion Dose of N-Acetylcysteine on Redox Status of the Body in Patients with Sepsis Admitted to the ICU

PURPOSE

Conflicting results exist regarding the efficacy of N-acetyl cysteine (NAC) in sepsis treatment. A pivotal factor affecting the therapeutic potency of NAC in sepsis is timing and dosing of its infusion. We aimed to assess the effect of NAC on redox status of patients with sepsis and to compare its efficacy in intermittent and continuous infusion with the objective of developing the infusion regimen and optimizing the timing.

MATERIALS AND METHODS

A prospective, randomized clinical trial was designed to compare the antioxidative effect of NAC in intermittent infusion group (IV: 25 mg/kg bolus and then 25 mg/kg/8 hours 3 times) and continuous infusion group (IV: 25 mg/kg bolus and then 75 mg/kg over 24 hours) in 60 critically ill patients with sepsis (20 patients in each group). Blood samples were collected immediately before and after intervention for total antioxidant capacity (TAC) and malondialdehyde (MDA) assessment.

RESULTS

N-acetyl cysteine considerably increased TAC levels in both intermittent (0.68 ± 0.60; P value = .036) and continuous (0.69 ± 0.64; P value = .015) infusion groups when compared to placebo (0.61 ± 0.10); however, the difference in TAC levels between the intermittent and the continuous infusion did not reach statistical significance (P value = .942). Likewise, NAC treatment decreased MDA levels in both intermittent (19.45 ± 4.18; P value = 0.001) and continuous (22.47 ± 6.68; P value = .002) infusion groups when compared to placebo (31.76 ± 11.06), while the difference in MDA levels between the intermittent and the continuous infusion did not reach statistical significance (P value = .481).

CONCLUSION

Our data confirmed the antioxidative effect of NAC treatment in patients with sepsis, with no significant difference in intermittent and continuous infusion.

UHPLC-Q-TOF MS-Based Metabolic Analysis for the Therapeutic Efficacy of "Xuebijing Injection" against Sepsis-Induced Acute Lung Injury

“Xuebijing Injection” (XBJ) is a traditional Chinese medicine and has been wildly used in the treatment of sepsis in China. However, few studies have reported the use of XBJ in sepsis with acute lung injury (ALI). This study aimed to investigate the therapeutic efficacy of XBJ against sepsis-induced ALI. Generally a total of 27 mice were equally randomized into three groups: a sham group was given saline before sham operation. A sepsis group received the cecal ligation and puncture (CLP) operation only. A sepsis+XBJ group, XBJ, was injected at 72, 48, and 24 h before CLP operation. The lung tissue was collected for UHPLC-Q-TOF/MS profiling analysis, biomarker identification, and pathway analysis. With the analysis of principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA), forty-five purine, amino acid, and sphingolipid metabolites in lung tissues were identified as potential biomarkers of sepsis-induced ALI, among which 22 were reversed in the sepsis+XBJ group significantly. Conclusively, our results suggest that purine metabolic pathway, glutathione metabolic pathway, sphingomyelin metabolic pathway, arachidonic acid metabolic pathway, and phospholipid metabolic pathway may be the potential therapeutic pathways to overcome sepsis-induced acute lung injury and we provided the potential mechanisms of protective effects of XBJ against ALI.

Flavin-Based Light-Driven Fluorescent Probe for the Detection of Antioxidant Amino Acids

We have synthesized a flavin-N(5)-oxide derivative with a p-toluenesulfonyl (Ts-OF) group as a "turn-on" fluorescent probe for the detection of several antioxidant amino acids and biothiols. Oxidized flavin was synthesized by using dithiothreitol as the reducing agent. Ts-OF showed a light-driven fluorescence enhancement in the presence of several amino acids and biothiols such as histidine (His), methionine (Met), cysteine (Cys), glutathione (GSH), and homocysteine (Hcy). The 1H NMR study indicated the reductive elimination of the p-toluenesulfonyl group from Ts-OF in the presence of antioxidants and photo-irradiation.

N-Acetylcysteine's Role in Sepsis and Potential Benefit in Patients With Microcirculatory Derangements

OBJECTIVE

To review the data surrounding the utility of N-acetylcysteine (NAC) in sepsis and identify areas needed for additional research.

DATA SOURCES

A review of articles describing the mechanisms of action and clinical use of NAC in sepsis.

SUMMARY OF REVIEW

Despite many advances in critical care medicine, still as many as 50% of patients with septic shock die. Treatments thus far have focused on resuscitation and restoration of macrocirculatory targets in the early phases of sepsis, with less focus on microcirculatory dysfunction. N-acetylcysteine, due to its anti-inflammatory and antioxidative properties, has been readily investigated in sepsis and has yielded largely incongruous and disappointing results. In addition to its known anti-inflammatory and antioxidative roles, one underappreciated property of NAC is its ability to vasodilate the microcirculation and improve locoregional blood flow. Some investigators have sought to capitalize on this mechanism with promising results, as evidenced by microcirculatory vasodilation, improvements in regional blood flow and oxygen delivery, and reductions in lactic acidosis, organ failure, and mortality.

CONCLUSION

In addition to its antioxidant and anti-inflammatory properties, N-acetylcysteine possesses vasodilatory properties that could benefit the microcirculation in sepsis. It is imperative that we investigate these properties to uncover NAC's full potential for benefit in sepsis.

Sepsis induces telomere shortening: a potential mechanism responsible for delayed pathophysiological events in sepsis survivors?

Sepsis survivors suffer from additional morbidities, including higher disk of readmissions, nervous system disturbances and cognitive dysfunction, and increased mortality, even several years after the initial episode of sepsis. In many ways, the phenotype of sepsis survivors resembles the phenotype associated with accelerated aging. Since telomere shortening is a hallmark of aging, we investigated whether sepsis also leads to telomere shortening. Male balb/c mice were divided into two groups: the control group received 100 μl of normal saline intraperitoneally; the sepsis group received 15 mg/kg of bacterial lipopolysaccharide i.p. After 48 hours, animals were sacrificed to collect blood, spleen and kidney. The human component of our study utilized blood samples obtained from patients in the Trauma Department and samples collected 7 days later in those patients who developed sepsis. Telomere length was measured by quantitative PCR. Since oxidative stress is a known inducer of telomere shortening, thiobarbituric acid reactive substances and superoxide dismutase (SOD) activity were analyzed in order to evaluate oxidative stress burden. Induction of endotoxemia in mice resulted in significant telomere shortening in spleen and kidney. Blood cells from patients that progressed to sepsis also exhibited a statistically significant reduction of telomere length. Endotoxemia in mice also induced an early-onset increase in oxidative stress markers, but was not associated with a downregulation of telomerase protein expression. We conclude that endotoxemia and sepsis induce telomere shortening in various tissues and hypothesize that this may contribute to the pathogenesis of the delayed pathophysiological events in sepsis survivors.

Effects of N-acetylcysteine (NAC) supplementation in resuscitation fluids on renal microcirculatory oxygenation, inflammation, and function in a rat model of endotoxemia

Background

Modulation of inflammation and oxidative stress appears to limit sepsis-induced damage in experimental models. The kidney is one of the most sensitive organs to injury during septic shock. In this study, we evaluated the effect of N-acetylcysteine (NAC) administration in conjunction with fluid resuscitation on renal oxygenation and function. We hypothesized that reducing inflammation would improve the microcirculatory oxygenation in the kidney and limit the onset of acute kidney injury (AKI).

Methods

Rats were randomized into five groups (n = 8 per group): (1) control group, (2) control + NAC, (3) endotoxemic shock with lipopolysaccharide (LPS) without fluids, (4) LPS + fluid resuscitation, and (5) LPS + fluid resuscitation + NAC (150 mg/kg/h). Fluid resuscitation was initiated at 120 min and maintained at fixed volume for 2 h with hydroxyethyl starch (HES 130/0.4) dissolved in acetate-balanced Ringer’s solution (Volulyte) with or without supplementation with NAC (150 mg/kg/h). Oxygen tension in the renal cortex (CμPO₂), outer medulla (MμPO₂), and renal vein was measured using phosphorimetry. Biomarkers of renal injury, inflammation, and oxidative stress were assessed in kidney tissues.

Results

Fluid resuscitation significantly improved the systemic and renal macrohemodynamic parameters after LPS. However, the addition of NAC further improved cortical renal oxygenation, oxygen delivery, and oxygen consumption (p < 0.05). NAC supplementation dampened the accumulation of NGAL or L-FABP, hyaluronic acid, and nitric oxide in kidney tissue (p < 0.01).

Conclusion

The addition of NAC to fluid resuscitation may improve renal oxygenation and attenuate microvascular dysfunction and AKI. Decreases in renal NO and hyaluronic acid levels may be involved in this beneficial effect. A therapeutic strategy combining initial fluid resuscitation with antioxidant therapies may prevent sepsis-induced AKI.

Assessment of oxidative stress after out-of-hospital cardiac arrest

INTRODUCTION

Pathophysiology of cardiac arrest corresponds to a whole body ischemia-reperfusion. This phenomenon is usually associated with an oxidative stress in various settings, but few data are available on cardiac arrest in human. The aim of the present study was to evaluate different oxidative stress markers in out-of-hospital cardiac arrest (OHCA) patients treated with therapeutic hypothermia.

MATERIALS AND METHODS

We conducted a prospective study assessing oxidative stress markers (thiobarbituric acid reactive species, carbonyls, thiols, glutathione, and glutathione peroxidase) in OHCA patients treated with therapeutic hypothermia. Measurements were performed during the 4 days after admission and compared between good and poor outcome patients according to Cerebral Performance Category.

RESULTS

Thirty-four patients were included, 10 good and 24 poor outcomes at 6 months. Thiobarbituric acid reactive species were higher in the poor outcome group on admission and when therapeutic hypothermia was reached. The other markers were not different between groups. No markers seemed modified by the use of therapeutic hypothermia in each group.

CONCLUSIONS

After OHCA, good outcome patients exhibit lower oxidative stress markers than poor outcome patients. Thiobarbituric acid reactive species appears to be an early prognostic parameter. Oxidative stress markers seem not mitigated by therapeutic hypothermia.

Fetal and Neonatal Effects of N-Acetylcysteine When Used for Neuroprotection in Maternal Chorioamnionitis

OBJECTIVE

To evaluate the clinical safety of antenatal and postnatal N-acetylcysteine (NAC) as a neuroprotective agent in maternal chorioamnionitis in a randomized, controlled, double-blinded trial.

STUDY DESIGN

Twenty-two mothers >24 weeks gestation presenting within 4 hours of diagnosis of clinical chorioamnionitis were randomized with their 24 infants to NAC or saline treatment. Antenatal NAC (100 mg/kg/dose) or saline was given intravenously every 6 hours until delivery. Postnatally, NAC (12.5-25 mg/kg/dose, n = 12) or saline (n = 12) was given every 12 hours for 5 doses. Doppler studies of fetal umbilical and fetal and infant cerebral blood flow, cranial ultrasounds, echocardiograms, cerebral oxygenation, electroencephalograms, and serum cytokines were evaluated before and after treatment, and 12, 24, and 48 hours after birth. Magnetic resonance spectroscopy and diffusion imaging were performed at term age equivalent. Development was followed for cerebral palsy or autism to 4 years of age.

RESULTS

Cardiovascular measures, cerebral blood flow velocity and vascular resistance, and cerebral oxygenation did not differ between treatment groups. Cerebrovascular coupling was disrupted in infants with chorioamnionitis treated with saline but preserved in infants treated with NAC, suggesting improved vascular regulation in the presence of neuroinflammation. Infants treated with NAC had higher serum anti-inflammatory interleukin-1 receptor antagonist and lower proinflammatory vascular endothelial growth factor over time vs controls. No adverse events related to NAC administration were noted.

CONCLUSIONS

In this cohort of newborns exposed to chorioamnionitis, antenatal and postnatal NAC was safe, preserved cerebrovascular regulation, and increased an anti-inflammatory neuroprotective protein.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00724594.

Systemic inflammation and oxidative stress post-lung resection: Effect of pretreatment with N-acetylcysteine

BACKGROUND AND OBJECTIVE

N-acetylcysteine has been used to treat a variety of lung diseases, where is it thought to have an antioxidant effect. In a randomized placebo-controlled double-blind study, the effect of N-acetylcysteine on systemic inflammation and oxidative damage was examined in patients undergoing lung resection, a human model of acute lung injury.

METHODS

Eligible adults were randomized to receive preoperative infusion of N-acetylcysteine (240 mg/kg over 12 h) or placebo. Plasma thiols, interleukin-6, 8-isoprostane, ischaemia-modified albumin, red blood cell glutathione and exhaled breath condensate pH were measured pre- and post-operatively as markers of local and systemic inflammation and oxidative stress.

RESULTS

Patients undergoing lung resection and one-lung ventilation exhibited significant postoperative inflammation and oxidative damage. Postoperative plasma thiol concentration was significantly higher in the N-acetylcysteine-treated group. However, there was no significant difference in any of the measured biomarkers of inflammation or oxidative damage, or in clinical outcomes, between N-acetylcysteine and placebo groups.

CONCLUSION

Preoperative administration of N-acetylcysteine did not attenuate postoperative systemic or pulmonary inflammation or oxidative damage after lung resection.

CLINICAL TRIAL REGISTRATION

NCT00655928 at ClinicalTrials.gov.

Results of liver transplantation in patients with acute liver failure due to Amanita phalloides and paracetamol (acetaminophen) intoxication

INTRODUCTION

Amanita phalloides and paracetamol intoxications are responsible for the majority of acute liver failures.

AIM

To assess survival outcomes and to analyse risk factors affecting survival in the studied group.

MATERIAL AND METHODS

Of 1369 liver transplantations performed in the Department of General, Transplant, and Liver Surgery, Medical University of Warsaw before December 2013, 20 (1.46%) patients with Amanita phalloides (n = 13, 0.95%) and paracetamol (n = 7, 0.51%) intoxication were selected for this retrospective study. Overall and graft survival at 5 years were set as primary outcome measures.

RESULTS

Five-year overall survival after liver transplantation in the studied group was 53.57% and 53.85% in patients with paracetamol and Amanita phalloides poisoning, respectively (p = 0.816). Five-year graft survival was 26.79% for patients with paracetamol and 38.46% with Amanita phalloides intoxication (p = 0.737). Risk factors affecting patient survival were: pre-transplant bilirubin concentration (p = 0.023) and higher number of red blood cells (p = 0.013) and fresh frozen plasma (p = 0.004) transfused intraoperatively. Likewise, higher number of red blood cells (p = 0.012) and fresh frozen plasma (p = 0.007) transfused were risk factors affecting 5-year graft survival. Surprisingly, donor and recipient blood type incompatibility was neither the risk factor for 5-year overall survival (p = 0.939) nor the risk factor for 5-year graft survival (p = 0.189).

CONCLUSIONS

In selected intoxicated patients urgent liver transplantation is the only successful modality of treatment. Risk factors affecting survival are in correspondence with the patient's pre-transplant status (bilirubin level in serum) and intraoperative status (number of red blood cells and fresh frozen plasma transfused).

Changes in glucose metabolism and reversion of genes expression in the liver of insulin-resistant rats exposed to malathion. The protective effects of N-acetylcysteine

Organophosphorus pesticides are known to disturb glucose homeostasis and increase incidence of metabolic disorders and diabetes via insulin resistance. The current study investigates the influence of malathion on insulin signaling pathways and the protective effects of N-acetylcysteine (NAC). Malathion (200 mg/kg) and NAC (2 g/l) were administered orally to rats, during 28 consecutive days. Malathion increases plasma glucose, plasma insulin and glycated hemoglobin levels. Further, we observed an increase of insulin resistance biomarkers and a decrease of insulin sensitivity indices. The GP, GSK3β and PEPCK mRNA expressions were amplified by malathion while, the expression of glucokinase gene is down-regulated. On the basis of biochemical and molecular findings, it is concluded that malathion impairs glucose homeostasis through insulin resistance and insulin signaling pathways disruptions in a way to result in a reduced function of insulin into hepatocytes. Otherwise, when malathion-treated rats were compared to NAC supplemented rats, fasting glucose and insulin levels, as well as insulin resistance indices were reduced. Furthermore, NAC restored liver GP and PEPCK expression. N-acetylcysteine showed therapeutic effects against malathion-induced insulin signaling pathways disruption in liver. These data support the concept that antioxidant therapies attenuate insulin resistance and ameliorate insulin sensitivity.

Studies of host-pathogen interactions and immune-related drug development using the silkworm: interdisciplinary immunology, microbiology, and pharmacology studies

Innate immunity acts as a front-line barrier against invading pathogens, and the majority of the components are widely conserved among species. Regulation of innate immunity is important for overcoming infections and preventing self-damaging sepsis. Using the silkworm (Bombyx mori) as an animal model, we elucidated the activation processes of innate immunity with emphasis on a multifunctional insect cytokine called paralytic peptide. Moreover, we established an ex vivo system using silkworm larval specimens to quantitatively evaluate the immunostimulatory activity of natural compounds. We observed that overactivation of innate immunity in silkworms induces tissue damage followed by host death, resembling sepsis-induced multi-organ failure in humans. Here, we summarize our recent findings and propose the usefulness of the silkworm as an animal model for studying immune regulation and for evaluating compounds with the potential to regulate innate immunity.

Dynamic changes in amino acid concentration profiles in patients with sepsis

Objectives

The goal of this work was to explore the dynamic concentration profiles of 42 amino acids and the significance of these profiles in relation to sepsis, with the aim of providing guidance for clinical therapies.

Methods

Thirty-five critically ill patients with sepsis were included. These patients were further divided into sepsis (12 cases) and severe sepsis (23 cases) groups or survivor (20 cases) and non-survivor (15 cases) groups. Serum samples from the patients were collected on days 1, 3, 5, 7, 10, and 14 following intensive care unit (ICU) admission, and the serum concentrations of 42 amino acids were measured.

Results

The metabolic spectrum of the amino acids changed dramatically in patients with sepsis. As the disease progressed further or with poor prognosis, the levels of the different amino acids gradually increased, decreased, or fluctuated over time. The concentrations of sulfur-containing amino acids (SAAs), especially taurine, decreased significantly as the severity of sepsis worsened or with poor prognosis of the patient. The serum concentrations of SAAs, especially taurine, exhibited weak negative correlations with the Sequential Organ Failure Assessment (SOFA) (r=-0.319) and Acute Physiology and Chronic Health Evaluation (APACHE) II (r=-0.325) scores. The areas under the receiver operating characteristic curves of cystine, taurine, and SAA levels and the SOFA and APACHE II scores, which denoted disease prognosis, were 0.623, 0.674, 0.678, 0.86, and 0.857, respectively.

Conclusions

Critically ill patients with disorders of amino acid metabolism, especially of SAAs such as cystine and taurine, may provide an indicator of the need for the nutritional support of sepsis in the clinic.

Trial Registration

ClinicalTrial.gov identifier NCT01818830.

Preservation of renal blood flow by the antioxidant EUK-134 in LPS-treated pigs

Sepsis is associated with an increase in reactive oxygen species (ROS), however, the precise role of ROS in the septic process remains unknown. We hypothesized that treatment with EUK-134 (manganese-3-methoxy N,N'-bis(salicyclidene)ethylene-diamine chloride), a compound with superoxide dismutase and catalase activity, attenuates the vascular manifestations of sepsis in vivo. Pigs were instrumented to measure cardiac output and blood flow in renal, superior mesenteric and femoral arteries, and portal vein. Animals were treated with saline (control), lipopolysaccharide (LPS; 10 µg·kg-1·h-1), EUK-134, or EUK-134 plus LPS. Results show that an LPS-induced increase in pulmonary artery pressure (PAP) as well as a trend towards lower blood pressure (BP) were both attenuated by EUK-134. Renal blood flow decreased with LPS whereas superior mesenteric, portal and femoral flows did not change. Importantly, EUK-134 decreased the LPS-induced fall in renal blood flow and this was associated with a corresponding decrease in LPS-induced protein nitrotyrosinylation in the kidney. PO2, pH, base excess and systemic vascular resistance fell with LPS and were unaltered by EUK-134. EUK-134 also had no effect on LPS-associated increase in CO. Interestingly, EUK-134 alone resulted in higher CO, BP, PAP, mean circulatory filling pressure, and portal flow than controls. Taken together, these data support a protective role for EUK-134 in the renal circulation in sepsis.

Efficacy of screening immune system function in at-risk newborns

This paper explores the introduction of a screening test to highlight impaired immune system status for newborn infants and its efficacy as a preventative clinical measure. Moreover, it is suggested that screening of the infantile immune system has the potential to highlight susceptibility to a range of infant and childhood diseases, bestowing an opportunity to introduce early intervention to reduce the incidence of these diseases. Development of the neonatal immune system is an important health issue, implicated in many childhood problems such as allergies, infection, and autoimmunity. The neonate has a limited immune system and ability to combat bacteria. Depleted levels of the tripeptide reduced glutathione (GSH) have been linked to numerous conditions and its intracellular level is acknowledged as an indicator of immune system function. Introduction of an immune system screening programme for infants is formally reviewed and assessed. Several benefits are reported in the treatment of impaired immune systems, a trial screening programme is proposed for at-risk infants to gather further evidence as to its efficacy. Infants at risk of impaired immune system function include cystic fibrosis, premature infants, and low birth weight infants. The interventions include breastfeeding, milk banks, and appropriate formula to support the immune system.

Antioxidant and anti-inflammatory effects of N-acetylcysteine against malathion-induced liver damages and immunotoxicity in rats

AIMS

Occupational exposure to organophosphate pesticides is becoming a common and increasingly alarming world-wide phenomenon. The present study is designed to investigate the preventive effect of N-acetylcysteine on malathion-induced hepatic injury and inflammation in rats.

MAIN METHODS

Adult male Wistar rats of body weight 200-230 g were used for the study. Malathion (200mg/kg b.w./day) was administered to rats by oral intubation and N-acetylcysteine (2g/l) in drinking water for 28 days. Rats were sacrificed on the 28th day, 2h after the last administration. Markers of liver injury (aspartate transaminase, alanine transaminase, alkaline phosphatase and lactate desyhdogenase), inflammation (leukocyte counts, myeloperoxidase, immunophenotyping of CD4(+) and CD8(+), interleukin-1β, interleukin-6 and interferon-γ expression) and oxidative stress (lipid peroxidation, reduced glutathione and antioxidant status) were assessed.

KEY FINDINGS

Malathion induced an increase in activities of hepatocellular enzymes in plasma, lipid peroxidation index, CD3(+)/CD4(+) and CD3(+)/CD4(+) percent and pro-inflammatory cytokines, when decreased antioxidant status in liver was noted. When malathion-treated rats were compared to NAC supplemented rats, leukocytosis, T cell count and IL-1β, IL-6, INF-γ expression were reduced. Furthermore, NAC restored liver enzyme activities and oxidative stress markers.

SIGNIFICANCE

Malathion induces hepatotoxicity, oxidative stress and liver inflammation. N-acetylcysteine showed therapeutic effects against malathion toxicity.

Interventions for preventing critical illness polyneuropathy and critical illness myopathy

BACKGROUND

Critical illness polyneuropathy or myopathy (CIP/CIM) is a frequent complication in the intensive care unit (ICU) and is associated with prolonged mechanical ventilation, longer ICU stay and increased mortality. This is an interim update of a review first published in 2009 (Hermans 2009). It has been updated to October 2011, with further potentially eligible studies from a December 2013 search characterised as awaiting assessment.

OBJECTIVES

To systematically review the evidence from RCTs concerning the ability of any intervention to reduce the incidence of CIP or CIM in critically ill individuals.

SEARCH METHODS

On 4 October 2011, we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE, and EMBASE. We checked the bibliographies of identified trials and contacted trial authors and experts in the field. We carried out an additional search of these databases on 6 December 2013 to identify recent studies.

SELECTION CRITERIA

All randomised controlled trials (RCTs), examining the effect of any intervention on the incidence of CIP/CIM in people admitted to adult medical or surgical ICUs. The primary outcome was the incidence of CIP/CIM in ICU, based on electrophysiological or clinical examination. Secondary outcomes included duration of mechanical ventilation, duration of ICU stay, death at 30 and 180 days after ICU admission and serious adverse events from the treatment regimens.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted the data and assessed the risk of bias in included studies.

MAIN RESULTS

We identified five trials that met our inclusion criteria. Two trials compared intensive insulin therapy (IIT) to conventional insulin therapy (CIT). IIT significantly reduced CIP/CIM in the screened (n = 825; risk ratio (RR) 0.65, 95% confidence interval (CI) 0.55 to 0.77) and total (n = 2748; RR 0.70, 95% CI 0.60 to 0.82) population randomised. IIT reduced duration of mechanical ventilation, ICU stay and 180-day mortality, but not 30-day mortality compared with CIT. Hypoglycaemia increased with IIT but did not cause early deaths.One trial compared corticosteroids with placebo (n = 180). The trial found no effect of treatment on CIP/CIM (RR 1.27, 95% CI 0.77 to 2.08), 180-day mortality, new infections, glycaemia at day seven, or episodes of pneumonia, but did show a reduction of new shock events.In the fourth trial, early physical therapy reduced CIP/CIM in 82/104 evaluable participants in ICU (RR 0.62. 95% CI 0.39 to 0.96). Statistical significance was lost when we performed a full intention-to-treat analysis (RR 0.81, 95% CI 0.60 to 1.08). Duration of mechanical ventilation but not ICU stay was significantly shorter in the intervention group. Hospital mortality was not affected but 30- and 180-day mortality results were not available. No adverse effects were noticed.The last trial found a reduced incidence of CIP/CIM in 52 evaluable participants out of a total of 140 who were randomised to electrical muscle stimulation (EMS) versus no stimulation (RR 0.32, 95% CI 0.10 to 1.01). These data were prone to bias due to imbalances between treatment groups in this subgroup of participants. After we imputed missing data and performed an intention-to-treat analysis, there was still no significant effect (RR 0.94, 95% CI 0.78 to 1.15). The investigators found no effect on duration of mechanical ventilation and noted no difference in ICU mortality, but did not report 30- and 180-day mortality.We updated the searches in December 2013 and identified nine potentially eligible studies that will be assessed for inclusion in the next update of the review.

AUTHORS' CONCLUSIONS

There is moderate quality evidence from two large trials that intensive insulin therapy reduces CIP/CIM, and high quality evidence that it reduces duration of mechanical ventilation, ICU stay and 180-day mortality, at the expense of hypoglycaemia. Consequences and prevention of hypoglycaemia need further study. There is moderate quality evidence which suggests no effect of corticosteroids on CIP/CIM and high quality evidence that steroids do not affect secondary outcomes, except for fewer new shock episodes. Moderate quality evidence suggests a potential benefit of early rehabilitation on CIP/CIM which is accompanied by a shorter duration of mechanical ventilation but without an effect on ICU stay. Very low quality evidence suggests no effect of EMS, although data are prone to bias. Strict diagnostic criteria for CIP/CIM are urgently needed for research purposes. Large RCTs need to be conducted to further explore the role of early rehabilitation and EMS and to develop new preventive strategies.

Peripheral 5-HT7 receptors as a new target for prevention of lung injury and mortality in septic rats

Sepsis is a complex pathophysiological event involving metabolic acidosis, systemic inflammatory response syndrome, tissue damage and multiple organ dysfunction syndrome. Although many new mechanisms are being investigated to enlighten the pathophysiology of sepsis, there is no effective treatment protocol yet. Presence of 5-HT7 receptors in immune tissues prompted us to hypothesize that these receptors have roles in inflammation and sepsis. We investigated the effects of 5-HT7 receptor agonists and antagonists on serum cytokine levels, lung oxidative stress, lung histopathology, nuclear factor κB (NF-κB) positivity and lung 5-HT7 receptor density in cecal ligation and puncture (CLP) induced sepsis model of rats. Agonist administration to septic rats increased survival time; decreased serum cytokine response against CLP; decreased oxidative stress and increased antioxidant system in lungs; decreased the tissue NF-κB immunopositivity, which is high in septic rats; and decreased the sepsis-induced lung injury. In septic rats, as a result of high inflammatory response, 5-HT7 receptor expression in lungs increased significantly and agonist administration, which decreased inflammatory response and related mortality, decreased the 5-HT7 receptor expression. In conclusion, all these data suggest that stimulation of 5-HT7 receptors may be a new therapeutic target for prevention of impaired inflammatory response related lung injury and mortality.

The beneficial effects of levetiracetam on polyneuropathy in the early stage of sepsis in rats: electrophysiological and biochemical evidence

ABSTRACT Critical illness polyneuropathy (CIP) is a common complication in long (≥1 week) critical/intensive care hospitalizations. Rapidly progressing atrophy and weakness of the limb, trunk and, particularly, respiratory muscles may lead to severe morbidity or mortality. The aim of the present study was to investigate the protective effects of levetiracetam (LEV) on CIP in the early stage of sepsis in rats. We simulated CIP by a surgically induced sepsis model and verified it by lower-limb electromyography (EMG) (amplitude and duration of CMAP, and distal latency). We evaluated the effects of various doses of LEV treatment (300, 600, and 1200 mg/kg i.p.) on CIP by performing electrophysiology, and determining plasma tumor necrosis factor (TNF)-α, lipid peroxides (malondialdehyde, MDA) levels, and total antioxidant capacity (TAC). Our data showed: (1) significant suppression of CMAP amplitude and prolongation of distal latency in the saline-treated sepsis group, and distal latency as well as CMAP amplitudes benefiting best from the 600 mg/kg LEV treatment; (2) significant rise in plasma TNF-α and MDA levels in the saline-treated sepsis group, but significant ameliorations by the 600 and 1200 mg/kg LEV treatment; (3) highly significant suppression of TAC in the saline-treated group, but profound reversals in all LEV-treated groups. We conclude that 300, 600, and 1200 mg/kg i.p. doses of post-septic treatment by LEV has possibly acted in a dose-dependent manner to both protect and restore the affected peripheral nerves' axon and myelin following surgical disturbance of the cecum to induce sepsis and consequent polyneuropathy.

Effect of N-acetylcysteine supplementation on intracellular glutathione, urine isoprostanes, clinical score, and survival in hospitalized ill dogs

BACKGROUND

Antioxidant depletion and lipid peroxidation have been correlated with disease severity and associated with poor outcomes.

HYPOTHESIS/OBJECTIVES

Supplementing dogs with N-acetylcysteine (NAC) during the first 48 hours of hospitalization will increase cysteine, normalize glutathione concentrations, and decrease the degree of lipid peroxidation associated with illness.

ANIMALS

Sixty systemically ill hospitalized client-owned dogs and 14 healthy control dogs.

METHODS

Randomized investigator-blinded, placebo-controlled prospective study. Dogs were randomized to treatment with NAC (n = 30) versus placebo (n = 30). Antioxidants, urine 8-isoprostane/creatinine (IP/Cr), and clinical score were determined before and after treatment with NAC. Glutathione, cysteine, and vitamin E concentrations were quantified using high-performance liquid chromatography. Atomic absorption spectroscopy and enzyme-linked immunosorbent assays were used to quantify selenium and isoprostane concentrations, respectively.

RESULTS

Ill dogs had significantly lower vitamin E concentrations (27 versus 55 μg/mL; P = .0005) as well as elevated IP/Cr ratios (872 versus 399 pg/mg; P = .0007) versus healthy dogs. NAC supplementation significantly increased plasma cysteine (8.67 versus 15.1 μM; P < .0001) while maintaining glutathione concentrations. Dogs in the placebo group experienced a statistically significant decrease in glutathione concentrations (1.49 versus 1.44 mM; P = .0463). Illness severity and survival were unchanged after short duration NAC supplementation.

CONCLUSIONS

Ill dogs experience systemic oxidative stress. Supplementation with NAC during the first 48 hours of hospitalization stabilized erythrocyte glutathione concentrations. The clinical impact of this supplementation and glutathione concentration stabilization was undetermined.

Antioxidant micronutrients in the critically ill: a systematic review and meta-analysis

INTRODUCTION

Critical illness is characterized by oxidative stress, which is a major promoter of systemic inflammation and organ failure due to excessive free radical production, depletion of antioxidant defenses, or both. We hypothesized that exogenous supplementation of trace elements and vitamins could restore antioxidant status, improving clinical outcomes.

METHODS

We searched computerized databases, reference lists of pertinent articles and personal files from 1980 to 2011. We included randomized controlled trials (RCTs) conducted in critically ill adult patients that evaluated relevant clinical outcomes with antioxidant micronutrients (vitamins and trace elements) supplementation versus placebo.

RESULTS

A total of 21 RCTs met inclusion criteria. When the results of these studies were statistically aggregated (n = 20), combined antioxidants were associated with a significant reduction in mortality (risk ratio (RR) = 0.82, 95% confidence interval (CI) 0.72 to 0.93, P = 0.002); a significant reduction in duration of mechanical ventilation (weighed mean difference in days = -0.67, 95% CI -1.22 to -0.13, P = 0.02); a trend towards a reduction in infections (RR= 0.88, 95% CI 0.76 to 1.02, P = 0.08); and no overall effect on ICU or hospital length of stay (LOS). Furthermore, antioxidants were associated with a significant reduction in overall mortality among patients with higher risk of death (>10% mortality in control group) (RR 0.79, 95% CI 0.68 to 0.92, P = 0.003) whereas there was no significant effect observed for trials of patients with a lower mortality in the control group (RR = 1.14, 95% 0.72 to 1.82, P = 0.57). Trials using more than 500 μg per day of selenium showed a trend towards a lower mortality (RR = 0.80, 95% CI 0.63 to 1.02, P = 0.07) whereas trials using doses lower than 500 μg had no effect on mortality (RR 0.94, 95% CI 0.67 to 1.33, P = 0.75).

CONCLUSIONS

Supplementation with high dose trace elements and vitamins may improve outcomes of critically ill patients, particularly those at high risk of death.

Comparison of melatonin and oxytocin in the prevention of critical illness polyneuropathy in rats with experimentally induced sepsis

BACKGROUND

Critical illness polyneuropathy is an acute neuromuscular disorder of critically ill patients and is characterized by limb and respiratory muscle weakness. The purpose of the study was to evaluate the neuroprotective effects of melatonin (MEL) and oxytocin (OT) on the early stage of sepsis by recording compound muscle action potentials and measuring plasma tumor necrosis factor (TNF)-α levels, lipid peroxidation (malondialdehyde; MDA), and total antioxidant capacity.

MATERIALS AND METHODS

One hundred adult male Sprague-Dawley rats were included in the study. The cecal ligation and puncture (CLP) procedure was performed to induce the sepsis model. MEL (10, 20, and 40 mg/kg), OT (0.4, 0.8, and 1.6 mg/kg), and a combination of MEL (20 mg/kg) and OT (0.8 mg/kg) were administered intraperitoneally in the first hour of surgery. Electromyography (EMG) studies were achieved 24 h after CLP surgery and then blood samples were collected for biochemical measurements.

RESULTS

EMG findings revealed that compound muscle action potential amplitude was significantly decreased and distal latency was prolonged in the CLP group compared with the sham group (P < 0.05 and P < 0.0005). Moreover, the animals that received CLP surgery showed significantly higher TNF-α and MDA levels and lower total antioxidant capacity values than the sham group. The administration of MEL and OT to rats significantly abolished the EMG alterations and suppressed oxidative stress and TNF-α release in CLP-induced rats.

CONCLUSIONS

The inflammatory processes and imbalance in oxidative/antioxidative status play important roles in the pathogenesis of critical illness polyneuropathy. We suggest that both oxytocin and melatonin may have beneficial effects against sepsis-induced polyneuropathy in critical illness.

Glutathione and glutathione analogues; therapeutic potentials

BACKGROUND

Glutathione (GSH) and related enzymes are critical to cell protection from toxins, both endogenous and environmental, including a number of anti-cancer cytotoxic agents.

SCOPE OF REVIEW

Enhancing GSH and associated enzymes represents a longtime and persistent aim in the search for cytoprotective strategies against cancer, neurologic degeneration, pulmonary and inflammatory conditions, as well as cardiovascular ailments. The challenge is to identify effective GSH analogues or precursors that generate mimic molecules with glutathione's cellular protective effects. This review will provide an update on these efforts. Much effort has also been directed at depleting cellular GSH and related cytoprotective effects, in order to sensitize established tumors to the cytotoxic effects of anti-cancer agents. Efforts to deplete GSH have been limited by the challenge of selectivity doing so in tumor and not in normal tissue so as to avoid enhancing the toxicity of anti-cancer drugs. This review will also provide an update of efforts at overcoming the challenge of targeting the desired GSH depletion to tumor cells.

MAJOR CONCLUSIONS

This chapter provides a brief background and update of progress in the development and use of GSH analogues in the therapeutic setting, including the pharmacological aspects of these compounds.

GENERAL SIGNIFICANCE

This is an area of enormous research activity, and major advances promise the advent of novel therapeutic opportunities in the near future. This article is part of a Special Issue entitled Cellular functions of glutathione.