A phase II, single-center, double-blind, randomized placebo-controlled trial to explore the efficacy and safety of intravenous melatonin in surgical patients with severe sepsis admitted to the intensive care unit

Efficacy of melatonin as adjunctive therapy for sepsis: A meta-analysis of randomized controlled trials

BACKGROUND

This study systematically evaluates the therapeutic efficacy of melatonin as an adjunctive therapy, aiming to determine its potential to reduce mortality and mitigate inflammatory responses in patients with sepsis.

METHODS

A search was conducted across PubMed, Web of Science, Cochrane Library, and Embase databases. The Cochrane Collaboration Risk of Bias (ROB) tool was systematically employed to assess the potential for bias in the relevant studies. The I² statistic was employed to evaluate heterogeneity among the studies. Potential publication bias was assessed using Begg's test. Sensitivity analysis was performed to examine the stability of the results. Additionally, a GRADE evaluation of the evidence level.

RESULTS

This meta-analysis encompassed a total of seven randomized controlled trials involving 421 patients diagnosed with sepsis. The primary results indicated that the mortality rate in the intervention group was significantly lower than that in the control group, suggesting that melatonin may effectively reduce mortality among sepsis patients [OR = 0.42, 95 % CI: 0.23-0.77, P = 0.005]. Additionally, the CRP levels in the intervention group were markedly lower than those in the control group, providing evidence that melatonin possesses anti-inflammatory properties that may help decrease inflammatory markers in sepsis patients [SMD= -4.00, 95 % CI: -6.47 to -1.53, P = 0.001]. Furthermore, Secondary outcome results showed no statistically significant differences in sequential organ failure assessment (SOFA) scores, length of hospital stay, and adverse effects. A sensitivity analysis confirmed the robustness of the findings from the included studies. By applying the GRADE system to evaluate the quality of evidence, we found the evidence in four grades: one rated as high quality, one as medium quality, and three rated as low quality.

CONCLUSION

Melatonin, when used as an adjuvant therapy, significantly reduces mortality and lowers the levels of the inflammatory marker CRP in patients with sepsis, while also improving their physical condition. However, due to the limited number and quality of the articles, these conclusions warrant further verification through the conduct of additional high-quality research.

A Focused Update to the Clinical Practice Guidelines for the Prevention and Management of Pain, Anxiety, Agitation/Sedation, Delirium, Immobility, and Sleep Disruption in Adult Patients in the ICU

RATIONALE

Critically ill adults are at risk for a variety of distressing and consequential symptoms both during and after an ICU stay. Management of these symptoms can directly influence outcomes.

OBJECTIVES

The objective was to update and expand the Society of Critical Care Medicine's 2018 Clinical Practice Guidelines for the Prevention and Management of Pain, Agitation/Sedation, Delirium, Immobility, and Sleep Disruption in Adult Patients in the ICU.

PANEL DESIGN

The interprofessional inclusive guidelines task force was composed of 24 individuals including nurses, physicians, pharmacists, physiotherapists, psychologists, and ICU survivors. The task force developed evidence-based recommendations using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. Conflict-of-interest policies were strictly followed in all phases of the guidelines, including task force selection and voting.

METHODS

The task force focused on five main content areas as they pertain to adult ICU patients: anxiety (new topic), agitation/sedation, delirium, immobility, and sleep disruption. Using the GRADE approach, we conducted a rigorous systematic review for each population, intervention, control, and outcome question to identify the best available evidence, statistically summarized the evidence, assessed the quality of evidence, and then performed the evidence-to-decision framework to formulate recommendations.

RESULTS

The task force issued five statements related to the management of anxiety, agitation/sedation, delirium, immobility, and sleep disruption in adults admitted to the ICU. In adult patients admitted to the ICU, the task force issued conditional recommendations to use dexmedetomidine over propofol for sedation, provide enhanced mobilization/rehabilitation over usual mobilization/rehabilitation, and administer melatonin. The task force was unable to issue recommendations on the administration of benzodiazepines to treat anxiety, and the use of antipsychotics to treat delirium.

CONCLUSIONS

The guidelines task force provided recommendations for pharmacologic management of agitation/sedation and sleep, and nonpharmacologic management of immobility in critically ill adults. These recommendations are intended for consideration along with the patient's clinical status.

Sepsis-induced cardiac dysfunction: mitochondria and energy metabolism

Sepsis is a life-threatening multi-organ dysfunction syndrome caused by dysregulated host response to infection, posing a significant global healthcare challenge. Sepsis-induced myocardial dysfunction (SIMD) is a common complication of sepsis, significantly increasing mortality due to its high energy demands and low compensatory reserves. The substantial mitochondrial damage rather than cell apoptosis in SIMD suggests disrupted cardiac energy metabolism as a crucial pathophysiological mechanism. Therefore, we systematically reviewed the mechanisms underlying energy metabolism dysfunction in SIMD, including alterations in myocardial cell energy metabolism substrates, excitation-contraction coupling processes, mitochondrial dysfunction, and mitochondrial autophagy and biogenesis, summarizing potential therapeutic targets within them.

Melatonin ameliorates inflammation and improves outcomes of ischemia/reperfusion injury in patients undergoing coronary artery bypass grafting surgery: a randomized placebo-controlled study

To investigate the protective role of high dose melatonin concerning myocardial I/R injury and inflammation in patients undergoing on-pump coronary artery bypass grafting (CABG) surgery by evaluating IR/inflammatory biomarkers and clinical outcomes. This was a prospective; randomized; single-blinded placebo-controlled study conducted at cardio-thoracic surgery department of the Academy of the Cardiovascular and Thoracic Surgery, Ain Shams University. Eligible patients were randomly allocated to; melatonin-treated group (MTG) or placebo-treated group (PTG). The MTG (n = 17) received 60 mg/day melatonin capsules daily starting 5 days before surgery in addition to the standard of care. PTG (n = 17) received placebo also 5 days before surgery plus standard of care. The levels of nuclear factor kappa beta (NF-κb) (primary outcome), tumor necrosis factor (TNF-α), cardiac troponins I, and IL-6 levels were all assessed for both groups at five time points: baseline before melatonin or placebo administration (T0), before cross-clamp application(T1), 5 min after cross-clamp removal(T2), 6 h after cross-clamp removal(T3) and 24 h after cross-clamp removal(T4). Blood pressure was assessed at baseline, pre-operative and 24-hours post-operative. The Quality of recovery-40 score (QOR-40) was assessed for both groups on day 4 after surgery. TNF-α levels decreased in the MTG at T1(p = 0.034) versus PTG. At T2(p = 0.005), and T3(p = 0.04), TNF-α significantly increased in PTG versus MTG. Troponins significantly increased in PTG at T3 (p = 0.04) versus MTG. NF-κB levels declined at T1 (p = 0.013) and T2 (p = 0.0001) in MTG compared to PTG. IL-6 significantly increased in PTG versus MTG at T3 (p = 0.04). The QOR-40 score significantly decreased in MTG versus PTG. MTG had statistically significant decrease in DBP compared to the placebo group (p = 0.024). MTG had a statistically significant shorter intubation time than did the placebo group (p = 0.03). Melatonin 60 mg was well-tolerated without any reported side effects. Our findings suggested that melatonin could ameliorate myocardial I/R injury after on-pump CABG and that this outcome was essentially correlated to its antiapoptotic and anti-inflammatory effects. Trial registration: ClinicalTrials.gov registration number NCT05552586, 9/2022.

Interplay between oxidative stress, neuroinflammatory cytokines and melatonin in Alzheimer's disease: Insights from cerebrospinal fluid analysis

Background

Among neurodegenerative disorders Alzheimer's disease (AD) displays the highest prevalence and the projected increase in its incidence will require new advances in early diagnosis and treatment, particularly for distinguishing AD from other dementias. While beta-amyloid (Aβ) and tau biomarkers are currently used to discriminate AD from other tauopathies and dementias, additional indicators could enhance patient stratification for specific dementia types. The present study was designed to find potential associations among the classic neurologic markers, Aβ, total and phospho-tau (T-tau and P-tau), with other biomarkers including melatonin and its oxidative-derived metabolite, Formyl-N-acetyl-5-methoxykynurenamine (AFMK) levels, assayed in patients' cerebrospinal fluid (CSF) taken previously for diagnostic purposes. Other factors previously associated with the aetiology of AD, including redox indicators or proinflammatory biomarkers, were also included.

Methods

The cross-sectional study included a cohort of 148 patients showing signs of dementia. A group of age-matched patients without neurological disorders were used as controls. CSF levels of Aβ, T-tau and P-tau were assayed, and patients were further classified according to threshold CSF levels of the three markers protein following the criteria of NIA-AA.

Results

Correlational and group analysis showed a positive association between oxidative stress and neuronal damage. TNF-α negatively correlated with CSF Aβ levels (amyloid plaques) while only RANTES/CCL5 correlated positively with T-tau and P-tau. Qualitative analysis of the proinflammatory cytokines assayed showed a higher detection level in Aβ-positive patients. Regarding melatonin in the CSF, indolamine levels did not correlate with its major oxidative-derived metabolite, i.e., AFMK. However, melatonin CSF levels were significantly reduced in AD patients but not in OT. On the contrary, AFMK showed the opposite pattern, with higher levels in samples from patients displaying high T-tau and P-tau levels. Neuroinflammation was associated with Aβ deposits (low concentration in CSF), while oxidative stress significantly correlated with high T-tau and P-tau levels. Finally, among all the parameters assayed in CSF samples from the cohort studied, P-tau, in combination with antioxidant capacity, offered the best ROC curve for the diagnostic capacity to discriminate between AD and OT, showing an 85 % specificity.

Conclusion

While oxidative stress is instead associated with high T- and P-tau levels, higher neuroinflammatory cytokines correlate with low CSF Aβ levels. An intriguing lack of correlation between neuroinflammation and melatonin found in this study could be as a result of sample size and requires further studies with a larger sample size. Even though indolamine levels in CSF drop significantly in AD, they do not correlate with AFMK, suggesting a different kynurenine synthesis source. None of them appear to discriminate between AD and OT. Finally, among all the parameters assayed in this study, P-tau in combination with antioxidant capacity, offered the best ROC curve for the diagnostic ability capacity to discriminate between AD and OT, showing an 85 % specificity. This study holds the potential to significantly improve patient stratification and contribute to the early diagnosis and treatment of Alzheimer's disease.

Melatonin from Plants: Going Beyond Traditional Central Nervous System Targeting-A Comprehensive Review of Its Unusual Health Benefits

Melatonin is indispensable for the homeostasis of plants and animals. In humans, it can help prevent or be an adjuvant treatment for several diseases mainly related to the immune system, inflammation, and oxidative stress. Moreover, a melatonin-rich diet is linked to several health benefits, such as regulation of circadian rhythm, regulation of the immunological system, epilepsy control, delaying the aging process, and diminishing hormones related to cancer. This review aimed to show the effects of melatonin in diseases beyond its traditional use. The results showed it can present scavenging of free radicals, reducing inflammatory cytokines, and modulating the immune system. Moreover, it can improve insulin resistance, blood pressure, LDL-c, adipose tissue mass, adhesion molecules, endothelial impairment, and plaque formation. These effects result in neuro- and cardioprotection, improvement of liver diseases, rheumatoid arthritis, dermatitis, COVID-19, polycystic ovaries, and sepsis. We conclude that plant melatonin can benefit patients with many diseases besides sleep problems and neurodegeneration. Plant melatonin may be more cost-effective and present fewer adverse events than synthetic. However, more clinical trials should be performed to show adequate doses, formulation, and treatment time.

Melatonin, an Antitumor Necrosis Factor Therapy

Tumor necrosis factor (TNF) is a biomarker of inflammation whose levels are elevated in patients with several diseases associated with dysregulation of the immune response. The main limitations of currently used anti-TNF therapies are the induction of immunodepression, which in many cases leads to serious adverse effects such as infection and cancer, and the inability to cross the blood-brain barrier in neuroinflammatory conditions. Melatonin, in addition to being a chronobiotic compound, is widely known for its antioxidant and immunomodulatory capacity to control inflammatory processes in different pathological contexts. The aim of the present review is to address human-based studies that describe the effect of melatonin on TNF production. The review includes all the articles published in PubMed databases until April 15, 2024. After depuration, 45 studies were finally included in the review, 23 related to the in vitro action of melatonin in human cells and 22 in vivo studies in humans. Most of the data reviewed support the idea that melatonin has an immunosuppressive effect on TNF levels, which, together with its low toxicity profile, low cost, and ability to cross the blood-brain barrier, points to melatonin as a potential anti-TNF therapy. Therefore, improving our knowledge of the action of melatonin in regulating TNF through appropriate clinical trials would reveal the true potential of this molecule as a possible anti-TNF therapy.

The emerging role of mtDNA release in sepsis: Current evidence and potential therapeutic targets

Sepsis is a systemic inflammatory reaction caused by infection, and severe sepsis can develop into septic shock, eventually leading to multiorgan dysfunction and even death. In recent years, studies have shown that mitochondrial damage is closely related to the occurrence and development of sepsis. Recent years have seen a surge in concern over mitochondrial DNA (mtDNA), as anomalies in this material can lead to cellular dysfunction, disruption of aerobic respiration, and even death of the cell. In this review, we discuss the latest findings on the mechanisms of mitochondrial damage and the molecular mechanisms controlling mitochondrial mtDNA release. We also explored the connection between mtDNA misplacement and inflammatory activation. Additionally, we propose potential therapeutic targets of mtDNA for sepsis treatment.

Bidirectional Interaction of Sepsis and Sleep Disorders: The Underlying Mechanisms and Clinical Implications

Sepsis is defined as life-threatening organ injury induced by infection, with high incidence and mortality. Sleep disorder is prevalent in septic patients and approximately 50% of patients with sepsis may develop atypical sleep patterns, but many of them may have been underdiagnosed by physicians. Sleep disorders and sepsis exhibit a close bidirectional relationship, with each condition significantly influencing the other. Conversely, sleep deprivation, sleep dysrhythmia and sleep fragmentation have been shown to impact the outcome of sepsis. This review endeavors to offer a comprehensive understanding of the intricate mechanisms that underpin the interplay between sepsis and sleep disorders, in addition to exploring potential clinical intervention strategies that could enhance outcomes for patients suffering from sepsis.

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.

Melatonin: A potential protective multifaceted force for sepsis-induced cardiomyopathy

Sepsis is a life-threatening condition manifested by organ dysfunction caused by a dysregulated host response to infection. Lung, brain, liver, kidney, and heart are among the affected organs. Sepsis-induced cardiomyopathy is a common cause of death among septic patients. Sepsis-induced cardiomyopathy is characterized by an acute and reversible significant decline in biventricular both systolic and diastolic function. This is accompanied by left ventricular dilatation. The pathogenesis underlying sepsis-induced cardiomyopathy is multifactorial. Hence, targeting an individual pathway may not be effective in halting the extensive dysregulated immune response. Despite major advances in sepsis management strategies, no effective pharmacological strategies have been shown to treat or even reverse sepsis-induced cardiomyopathy. Melatonin, namely, N-acetyl-5-methoxytryptamine, is synthesized in the pineal gland of mammals and can also be produced in many cells and tissues. Melatonin has cardioprotective, neuroprotective, and anti-tumor activity. Several literature reviews have explored the role of melatonin in preventing sepsis-induced organ failure. Melatonin was found to act on different pathways that are involved in the pathogenesis of sepsis-induced cardiomyopathy. Through its antimicrobial, anti-inflammatory, and antioxidant activity, it offers a potential role in sepsis-induced cardiomyopathy. Its antioxidant activity is through free radical scavenging against reactive oxygen and nitrogen species and modulating the expression and activity of antioxidant enzymes. Melatonin anti-inflammatory activities control the overactive immune system and mitigate cytokine storm. Also, it mitigates mitochondrial dysfunction, a major mechanism involved in sepsis-induced cardiomyopathy, and thus controls apoptosis. Therefore, this review discusses melatonin as a promising drug for the management of sepsis-induced cardiomyopathy.

Potential Neuroprotective Role of Melatonin in Sepsis-Associated Encephalopathy Due to Its Scavenging and Anti-Oxidative Properties

Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. The brain is one of the organs involved in sepsis, and sepsis-induced brain injury manifests as sepsis-associated encephalopathy (SAE). SAE may be present in up to 70% of septic patients. SAE has a very wide spectrum of clinical symptoms, ranging from mild behavioral changes through cognitive disorders to disorders of consciousness and coma. The presence of SAE increases mortality in the population of septic patients and may lead to chronic cognitive dysfunction in sepsis survivors. Therefore, therapeutic interventions with neuroprotective effects in sepsis are needed. Melatonin, a neurohormone responsible for the control of circadian rhythms, exerts many beneficial physiological effects. Its anti-inflammatory and antioxidant properties are well described. It is considered a potential therapeutic factor in sepsis, with positive results from studies on animal models and with encouraging results from the first human clinical trials. With its antioxidant and anti-inflammatory potential, it may also exert a neuroprotective effect in sepsis-associated encephalopathy. The review presents data on melatonin as a potential drug in SAE in the wider context of the pathophysiology of SAE and the specific actions of the pineal neurohormone.