Association between total antioxidant capacity and mortality in ischemic stroke patients

Melatonin: a promising neuroprotective agent for cerebral ischemia-reperfusion injury

Cerebral ischemia-reperfusion (CIR) injury is initiated by the generation of reactive oxygen species (ROS), which leads to the oxidation of cellular proteins, DNA, and lipids as an initial event. The reperfusion process impairs critical cascades that support cell survival, including mitochondrial biogenesis and antioxidant enzyme activity. Failure to activate prosurvival signals may result in increased neuronal cell death and exacerbation of CIR damage. Melatonin, a hormone produced naturally in the body, has high concentrations in both the cerebrospinal fluid and the brain. However, melatonin production declines significantly with age, which may contribute to the development of age-related neurological disorders due to reduced levels. By activating various signaling pathways, melatonin can affect multiple aspects of human health due to its diverse range of activities. Therefore, understanding the underlying intracellular and molecular mechanisms is crucial before investigating the neuroprotective effects of melatonin in cerebral ischemia-reperfusion injury.

The Role of Potential Oxidative Biomarkers in the Prognosis of Acute Ischemic Stroke and the Exploration of Antioxidants as Possible Preventive and Treatment Options

Ischemic strokes occur when the blood supply to a part of the brain is interrupted or reduced due to arterial blockage, and it often leads to damage to brain cells or death. According to a myriad of experimental studies, oxidative stress is an important pathophysiological mechanism of ischemic stroke. In this narrative review, we aimed to identify how the alterations of oxidative stress biomarkers could suggest a severity-reflecting diagnosis of ischemic stroke and how these interactions may provide new molecular targets for neuroprotective therapies. We performed an eligibility criteria-based search on three main scientific databases. We found that patients with acute ischemic stroke are characterized by increased oxidative stress markers levels, such as the total antioxidant capacity, F2-isoprostanes, hydroxynonenal, total and perchloric acid oxygen radical absorbance capacity (ORACTOT and ORACPCA), malondialdehyde (MDA), myeloperoxidase, and urinary 8-oxo-7,8-dihydro-2′-deoxyguanosine. Thus, acute ischemic stroke is causing significant oxidative stress and associated molecular and cellular damage. The assessment of these molecular markers could be useful in diagnosing ischemic stroke, finding its causes, predicting its severity and outcomes, reducing its impact on the cellular structures of the brain, and guiding preventive treatment towards antioxidant-based therapy as novel therapeutic alternatives.

Balance of the prooxidant and antioxidant system is associated with mortality in critically ill patients

It is well known that oxidative stress causes certain diseases and organ damage. However, roles of oxidative stress in the acute phase of critical patients remain to be elucidated. This study aimed to investigate the balance of oxidative and antioxidative system and to clarify the association between oxidative stress and mortality in critically ill patients. This cohort study enrolled 247 patients transported to our emergency department by ambulance. Blood was drawn on hospital arrival, and serum derivatives of reactive oxidant metabolites (dROMs, oxidative index) and biological antioxidant potential (BAP, antioxidative index) were measured. Modified ratio (MR) is also calculated as BAP/dROMs/7.51. There were 197 survivors and 50 non-survivors. In the non-survivors, dROMs were significantly lower (274 vs 311, p<0.01), BAP was significantly higher (2,853 vs 2,138, p<0.01), and MR was significantly higher (1.51 vs 0.92, p<0.01) compared to those in the survivors. The AUC of MR was similar to that for the APACHE II score. Contrary to our expectations, higher BAP and lower dROMs were observed on admission in non-survivors. This may suggest that the antioxidative system is more dominant in the acute phase of severe insults and that the balance toward a higher antioxidative system is associated with mortality.

Oxidative stress in cerebrovascular disease and associated diseases

Cellular aging is the most severe risk factor for neurodegenerative disease. Simultaneously, oxidative stress (OS) is a critical factor in the aging process, resulting from an imbalance between reactive oxygen and nitrogen species and the antioxidant defense system. Emerging evidence indicates that OS is a common cause of several age-related brain pathologies, including cerebrovascular diseases. Elevated OS disrupts endothelial functional ability by diminishing the bioavailability of nitric oxide (a vascular dilator), induces atherosclerosis, and impairs vasculature, which are all common characteristics of cerebrovascular disease. In this review, we summarize evidence supporting an active role of OS in cerebrovascular disease progression, focusing primarily on stroke pathogenesis. We briefly discuss hypertension, diabetes, heart disease, and genetic factors that are often linked to OS and are considered associated factors influencing stroke pathology. Finally, we discuss the current pharmaceutics/therapeutics available for treating several cerebrovascular diseases.

Oxidative stress markers-driven prognostic model to predict post-discharge mortality in heart failure with reduced ejection fraction

Background

Current predictive models based on biomarkers reflective of different pathways of heart failure with reduced ejection fraction (HFrEF) pathogenesis constitute a useful tool for predicting death risk among HFrEF patients. The purpose of the study was to develop a new predictive model for post-discharge mortality risk among HFrEF patients, based on a combination of clinical patients’ characteristics, N-terminal pro-B-type Natriuretic peptide (NT-proBNP) and oxidative stress markers as a potentially valuable tool for routine clinical practice.

Methods

116 patients with stable HFrEF were recruited in a prospective single-center study. Plasma levels of NT-proBNP and oxidative stress markers [superoxide dismutase (SOD), glutathione peroxidase (GPX), uric acid (UA), total bilirubin (TB), gamma-glutamyl transferase (GGT) and total antioxidant capacity (TAC)] were measured in the stable predischarge condition. Generalized linear model (GLM), random forest and extreme gradient boosting models were developed to predict post-discharge mortality risk using clinical and laboratory data. Through comprehensive evaluation, the most performant model was selected.

Results

During a median follow-up of 525 days (7–930), 33 (28%) patients died. Among the three created models, the GLM presented the best performance for post-discharge death prediction in HFrEF. The predictors included in the GLM model were age, female sex, beta blockers, NT-proBNP, left ventricular ejection fraction (LVEF), TAC levels, admission systolic blood pressure (SBP), angiotensin-converting enzyme inhibitors/angiotensin receptor II blockers (ACEI/ARBs) and UA levels. Our model had a good discriminatory power for post-discharge mortality [The area under the curve (AUC) = 74.5%]. Based on the retained model, an online calculator was developed to allow the identification of patients with heightened post-discharge death risk.

Conclusion

In conclusion, we created a new and simple tool that may allow the identification of patients at heightened post-discharge mortality risk and could assist the treatment decision-making.

The Influence of Oxidative Stress on Neurological Outcomes in Spontaneous Intracerebral Hemorrhage

Spontaneous intracerebral hemorrhage (ICH) causes, besides the primary brain injury, a secondary brain injury (SBI), which is induced, amongst other things, by oxidative stress (OS) and inflammation, determining the patient’s outcome. This study aims to assess the impact of OS in plasma and cerebrospinal fluid (CSF) on clinical outcomes in patients with ICH. A total of 19 ICH (volume > 30 cc) patients and 29 control patients were included. From day one until seven, blood and CSF samples were obtained, and ICH volume was calculated. OS markers, like malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), glutathione-sulfhydryl (GSH), and the total antioxidant status (TAS) were measured. Clinical data on treatment and outcome were determined. Patients with mRS ≤ 4 showed significantly elevated SOD and GSH-Px levels in plasma compared to patients with poor CO (p = 0.004; p = 0.002). Initial increased TAS in plasma and increased MDA in CSF were linked to an unfavorable outcome after six months (p = 0.06, r = 0.45; p = 0.05, r = 0.44). A higher ICH volume was associated with a worse outcome at week six (p = 0.04, r = 0.47). OS plays a significant role in SBI. Larger ICHs, elevated MDA in CSF, and TAS in plasma were associated with a detrimental outcome, whereas higher plasma-SOD and -GSH-Px were associated with a favorable outcome.

Biomarkers Predictive of Long-Term Outcome After Ischemic Stroke: A Meta-Analysis

BACKGROUND AND PURPOSE

The goal of this study was to systematically review the utility of serum biomarkers in the setting of ischemic stroke (IS) to predict long-term outcome.

METHODS

A systematic literature review was performed using the PubMed and MEDLINE databases for studies published between 1986-2018. All studies assessing long-term functional outcome (defined as 30 days or greater) following IS with respect to serum biomarkers were included. Data were extracted and pooled using a meta-analysis of odds ratios.

RESULTS

Of the total 2928 articles in the original literature search, 183 studies were ultimately selected. A total of 127 serum biomarkers were included. Biomarkers were grouped into several categories: inflammatory (32), peptide/enzymatic (30), oxidative/metabolic (28), hormone/steroid based (23), and hematologic/vascular (14). The most commonly studied biomarkers in each category were found to be CRP, S100β, albumin, copeptin, and D-dimer. With the exception of S100β, all were found to be statistically associated with >30-day outcome after ischemic stroke.

CONCLUSIONS

Serum-based biomarkers have the potential to predict functional outcome in IS patients. This meta-analysis has identified CRP, albumin, copeptin, and D-dimer to be significantly associated with long-term outcome after IS. These biomarkers have the potential to serve as a platform for prognosticating stroke outcomes after 30 days. These serum biomarkers, some of which are routinely ordered, can be combined with imaging biomarkers and used in artificial intelligence algorithms to provide refined predictive outcomes after injury. Ultimately these tools will assist physicians in providing guidance to families with regards to long-term independence of patients.

Decreased Superoxide Dismutase Concentrations (SOD) in Plasma and CSF and Increased Circulating Total Antioxidant Capacity (TAC) Are Associated with Unfavorable Neurological Outcome after Aneurysmal Subarachnoid Hemorrhage

Background: Subarachnoid hemorrhage (SAH) is a devastating disease with high morbidity and mortality. Hypoxia-induced changes and hemoglobin accumulation within the subarachnoid space are thought to lead to oxidative stress, early brain injury, and delayed vasospasm. This study aimed to evaluate the antioxidant status and its impact on neurological outcome in patients with aneurysmal SAH. Methods: In this prospective observational study, 29 patients with aneurysmal SAH were included (mean age 54.7 ± 12.4). Blood and cerebrospinal fluid (CSF) samples were collected on days (d) 1, 3, and 7. In addition, 29 patients without intracranial hemorrhage served as controls. The antioxidant system was analyzed by glutathione peroxidase (GSH-Px; U/L) and total and free glutathione-sulfhydryl (GSH; mg/L) in the plasma. Superoxide dismutase (SOD, U/mL) and total antioxidant capacity (TAC, µmol/L) were measured in the serum and CSF. Clinical data were compiled on admission (Hunt and Hess grade, Fisher grade, and GCS). Neurological and cognitive outcome (modified Rankin scale (mRS), Glasgow Outcome Scale Extended (GOSE) and Montreal Cognitive Assessment (MoCA)) was assessed after 6 weeks (6 w) and 6 months (6 m). Results: Plasma levels of SOD increased from day 1 to 7 after SAH (d1: 1.22 ± 0.36 U/L; d3: 1.25 ± 0.33 U/L, p = 0.99; d7: 1.52 ± 0.4 U/L, p = 0.019) and were significantly higher compared to controls (1.11 ± 0.27 U/L) at day 7 (p < 0.001). Concordantly, CSF levels of SOD increased from day 1 to 7 after SAH (d1: 1.22 ± 0.41 U/L; d3: 1.77 ± 0.73 U/L, p = 0.10; d7: 2.37 ± 1.29 U/L, p < 0.0001) without becoming significantly different compared to controls (1.74 ± 0.8 U/L, p = 0.09). Mean plasma TAC at day 1 (d1: 77.87 ± 49.72 µmol/L) was not statistically different compared to controls (46.74 ± 32.42 µmol/L, p = 0.25). TAC remained unchanged from day 1 to 7 (d3: 92.64 ± 68.58 µmol/L, p = 0.86; d7: 74.07 ± 54.95 µmol/L, p = 0.8) in plasma. TAC in CSF steeply declined from day 1 to 7 in patients with SAH becoming significantly different from controls at days 3 and 7 (d3: 177.3 ± 108.7 µmol/L, p = 0.0046; d7: 85.35 ± 103.9 µmol/L, p < 0.0001). Decreased SOD levels in plasma and CSF are associated with a worse neurological outcome 6 weeks (mRS: CSF p = 0.0001; plasma p = 0.027/GOSE: CSF p = 0.001; plasma p = 0.001) and 6 months (mRS: CSF p = 0.001; plasma p = 0.09/GOSE: CSF p = 0.001; plasma p = 0.001) after SAH. Increased plasma TAC correlated with a worse neurological outcome 6 weeks (mRS: p = 0.001/GOSE p = 0.001) and 6 months (mRS p = 0.001/GOSE p = 0.001) after SAH. Conclusion: In our study, a reduction in the antioxidative enzyme SOD and elevated TAC were associated with a poorer neurological outcome reflected by mRS and GOSE at 6 weeks and 6 months after SAH. A lower initial SOD CSF concentration was associated with the late deterioration of cognitive ability. These findings support the mounting evidence of the role of oxidative stress in early brain injury formation and unfavorable outcome after SAH.

Therapeutic Potential of Saffron (Crocus sativus L.) in Ischemia Stroke

Stroke is the second leading cause of death and a main cause of disability worldwide. The majority (approximately 80%) of strokes are ischemic. Saffron (Crocus sativus L.) has been considered for medicinal purposes since ancient times. Pharmacological effects of saffron are attributed to the presence of crocin, crocetin, picrocrocin, and safranal. In the present review, we summarized the reported neuroprotective effects of saffron and its active constituents against cerebral ischemia stroke. Saffron and its components exert its beneficial effects as an antioxidant, anti-inflammatory, and antiapoptotic agent though inhibition of biochemical, inflammatory, and oxidative stress markers. Taken together, this review indicates that saffron and its ingredients could be a potent candidate in the process of new drug production for the treatment of ischemia stroke.

The Antioxidant Role of One-Carbon Metabolism on Stroke

One-carbon (1C) metabolism is a metabolic network that is centered on folate, a B vitamin; it integrates nutritional signals with biosynthesis, redox homeostasis, and epigenetics. This metabolic pathway also reduces levels of homocysteine, a non-protein amino acid. High levels of homocysteine are linked to increased risk of hypoxic events, such as stroke. Several preclinical studies have suggested that 1C metabolism can impact stroke outcome, but the clinical data are unclear. The objective of this paper was to review preclinical and clinical research to determine whether 1C metabolism has an antioxidant role on stroke. To accomplish the objective, we searched for publications using the following medical subject headings (MeSH) keywords: antioxidants, hypoxia, stroke, homocysteine, one-carbon metabolism, folate, methionine, and dietary supplementation of one-carbon metabolism. Both pre-clinical and clinical studies were retrieved and reviewed. Our review of the literature suggests that deficiencies in 1C play an important role in the onset and outcome of stroke. Dietary supplementation of 1C provides beneficial effects on stroke outcome. For stroke-affected patients or individuals at high risk for stroke, the data suggest that nutritional modifications in addition to other therapies could be incorporated into a treatment plan.

High serum levels of TAC and early mortality in patients with spontaneous intracerebral haemorrhage

OBJECTIVE

Oxidation contributes to secondary brain injury after spontaneous intracerebral haemorrhage (SIH). One study found lower levels of total antioxidant capacity (TAC) in the blood in patients with SIH than in healthy subjects. However, there are no data on blood TAC levels and survival in patients with SIH. Therefore, the objective of our study was to determine if an association exists between serum TAC levels and mortality in patients with SIH.

METHODS

We included patients with severe supratentorial SIH. We considered severe when Glasgow Coma Scale (GCS) < 9. Patients from 6 Spanish hospitals were included in this observational and prospective study. Serum TAC levels at days 1, 4 and 8 of SIH were determined. Thirty-day mortality was our end-point study.

RESULTS

Non-surviving patients compared with surviving patients showed higher serum TAC levels at day 1 (p < 0.001), 4 (p < 0.001) and 8 (p = 0.001). An area under the curve was found for the prediction of 30-day mortality by serum TAC levels of 0.92 (95% CI = 0.85-96%; p < 0.001). Multiple logistic regression analysis showed an association of serum TAC levels with 30-day mortality (odds ratio = 16.513; 95% CI = 2.548-107.015; p = 0.003) controlling for midline shift, glycemia, early evacuation of SIH, intracerebral haemorrhage (ICH) score, age and volume of SIH.

CONCLUSIONS

The new findings of this study are that serum TAC levels are higher in non-surviving than in surviving patients, and that they are associated with mortality and could be used to predict mortality.

Liquid biopsy markers for stroke diagnosis

INTRODUCTION

There is a short time window (4.5 h) for the effective treatment of acute ischemic stroke (AIS), which uses recombinant tissue plasminogen activator (rt-PA). Unfortunately, this short therapeutic timeframe is a contributing factor to the relatively small number of patients (~7%) that receive rt-PA. While neuroimaging is the major diagnostic for AIS, more timely decisions could be made using a molecular diagnostic.

AREAS COVERED

In this review, we survey neuroimaging techniques used to diagnose stroke and their limitations. We also highlight the potential of various molecular/cellular biomarkers, especially peripheral blood-based (i.e. liquid biopsy) biomarkers, for diagnosing stroke to allow for precision decisions on managing stroke in a timely manner. Both protein and nucleic acid molecular biomarkers are reviewed. In particular, mRNA markers are discussed for AIS and hemorrhagic stroke diagnosis sourced from both cells and extracellular vesicles.

EXPERT OPINION

While there are a plethora of molecular markers for stroke diagnosis that have been reported, they have yet to be FDA-cleared. Possible reasons include the inability for these markers to appear in sufficient quantities for highly sensitive clinical decisions within the rt-PA therapeutic time.

The relationship between oxidative stress and acute ischemic stroke severity and functional outcome

Background

Cerebral ischemia initiates an oxidative stress response in the brain which is a composite process that involves many oxidative stress biomarkers. High levels of malondialdehyde (MDA) in patients with acute ischemic stroke had been found. The evaluation of oxidative stress in the acute stage may contribute to improve the post ischemic stroke outcome.

Objective

The aim of the current study to assess MDA level, as an oxidative stress biomarker, in acute ischemic stroke on admission and its relation with stroke severity on admission and also, its relation with three months short-term outcome.

Methods

Forty-two patients (20 males and 22 females) with acute ischemic stroke were prospectively enrolled in follow-up cohort study. Serum MDA was measured within 24 h after admission. We studied the relationship between MDA and stroke severity and functional outcome after 3 months assessed by National Institute of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS) respectively.

Results

Serum MDA levels correlated significantly with clinical short-term stroke outcome after 3 months (p < 0.001).

Conclusion(s)

These data provide evidence that the MDA (an oxidative stress biomarker) may be used as predictor for functional outcome in acute ischemic stroke.

Targeting Oxidative Stress and Inflammation to Prevent Ischemia-Reperfusion Injury

The cerebral ischemia injury can result in neuronal death and/or functional impairment, which leads to further damage and dysfunction after recovery of blood supply. Cerebral ischemia/reperfusion injury (CIRI) often causes irreversible brain damage and neuronal injury and death, which involves many complex pathological processes including oxidative stress, amino acid toxicity, the release of endogenous substances, inflammation and apoptosis. Oxidative stress and inflammation are interactive and play critical roles in ischemia/reperfusion injury in the brain. Oxidative stress is important in the pathological process of ischemic stroke and is critical for the cascade development of ischemic injury. Oxidative stress is caused by reactive oxygen species (ROS) during cerebral ischemia and is more likely to lead to cell death and ultimately brain death after reperfusion. During reperfusion especially, superoxide anion free radicals, hydroxyl free radicals, and nitric oxide (NO) are produced, which can cause lipid peroxidation, inflammation and cell apoptosis. Inflammation alters the balance between pro-inflammatory and anti-inflammatory factors in cerebral ischemic injury. Inflammatory factors can therefore stimulate or exacerbate inflammation and aggravate ischemic injury. Neuroprotective therapies for various stages of the cerebral ischemia cascade response have received widespread attention. At present, neuroprotective drugs mainly include free radical scavengers, anti-inflammatory agents, and anti-apoptotic agents. However, the molecular mechanisms of the interaction between oxidative stress and inflammation, and their interplay with different types of programmed cell death in ischemia/reperfusion injury are unclear. The development of a suitable method for combination therapy has become a hot topic.

Evaluating the Role of Oxidative Stress in Acute Ischemic Stroke

Background The role of oxidative stress in neuronal injury due to ischemic stroke has been an interesting topic in stroke research. Malondialdehyde (MDA) has emerged as a sensitive oxidative stress biomarker owing to its ability to react with the lipid membranes. Total antioxidant power (TAP) is another biomarker to estimate the total oxidative stress in stroke patients. We aimed to determine the oxidative stress in acute stroke patients by measuring MDA and TAP.

Materials and Methods MDA and TAP were determined in 100 patients with ischemic stroke and compared with that in 100 age- and sex-matched healthy adults. Demographic data, stroke severity measured by the National Institutes of Health Stroke Scale (NIHSS), and disability measured by the Barthel index (BI) were recorded. The association of MDA and TAP with other variables was analyzed by paired t -test.

Results Of the whole sample, 74% represented males. The mean NIHSS score was 13.11 and BI was 38.87. MDA was significantly higher in stroke patients (7.11 ± 1.67) than in controls (1.64 ± 0.82; p = 0.00). TAP was significantly lower in stroke patients (5.72 ± 1.41) than in controls (8.53 ± 2.4; p = 0.00). The lipid profile and blood sugar levels were also significantly higher in stroke patients. There was no association of MDA and TAP with other variables.

Conclusion We found that oxidative stress was associated with acute ischemic stroke. However, we could not establish an association between oxidative stress and the severity of acute stroke.

Total Antioxidant Capacity Predicts Outcome in Acute Ischemic Stroke Subtypes in Egyptian Patients

BACKGROUND

Oxidative stress after ischemic stroke contributes to neuronal cell injury. We tried to demonstrate an association between total antioxidant capacity (TAC) levels and outcomes after acute ischemic stroke (AIS).

METHODS

We enrolled 60 patients (36 females and 24 males) who were admitted to our hospital due to AIS, in addition to 30 age and sex-matched healthy controls. TAC levels were measured on day 1 of stroke onset, the relationships between TAC levels, stroke subtypes, and clinical outcomes based on the National Institutes of Health Stroke Scale and modified Rankin scale upon discharge were evaluated.

RESULTS

TAC levels were significantly lower in AIS patients than control (P < .001) being much lower in patients with large-vessel cerebral infarction than in those with small-vessel infarction. We investigated whether TAC concentrations reflected the severity and outcome of ischemic stroke and we found a significantly lower concentration of TAC in the poor outcome group than in the good outcome group (P < .001).

CONCLUSIONS

Our findings suggested that the biochemical changes related to TAC and oxidative stress may be considered a marker of ischemic brain injury and clinical outcome of ischemic stroke.

Lipid metabolic changes in rat brain during permanent cerebral ischemia

With each year, millions of people remain targeted by brain stroke, it still is by all means a global concern of the mankind. Despite all efforts to understand this disease better, there is still a lack of information on pathophysiology of ischemic stroke. Scrutinized data on biochemical changes at early stages of ischemia may help understand the mechanisms of the disorder and possibly reveal ways to finding the cure. The key role in the pathogenesis of stroke belongs to lipids as well as to the molecules associated with their biosynthesis and functionality. On the one hand, stroke evokes a deep oxidative stress leading to damage to biomolecules including lipids while on the other hand, due to the lack of reducing equivalents, the cellular biosynthesis processes are interrupted. The focus of this work was to study the changes taking place in the tissues of rat brain as a result of ischemia including estimation of levels of total cholesterol, FFA, MDA, GSH, and NADP(H). It was shown that in 24 hours from the onset of ischemia, there was a significant decrease in levels of FFA, total cholesterol and GSH, and an increase in the level of MDA, a marker of lipid peroxidation. NADP(H) pool level decreases twice in 6 hours from MCAO.

Antioxidant effect of myricitrin on hyperglycemia-induced oxidative stress in C2C12 cell

Hyperglycemia induced oxidative stress inside the cells. Myricitrin, as an antioxidant plant-derived component, may be useful in hyperglycemia. Hence, the aim of this study was conducted to evaluate the antioxidant effects of myricitrin on hyperglycemia-induced oxidative damage in myotubes (C2C12 cells). In this experimental study, mouse myoblast cell line (C2C12) was obtained and divided into five groups: control, hyperglycemia, hyperglycemia + myricitrin 1, 3, and 10 μM. After treatment period for 48 h, cells were collected, homogenized, and centrifuged at 2000 rpm for 10 min. All samples were kept at - 80 °C until experimental and real-time PCR assessments were performed. Hyperglycemia increased malondialdehyde (MDA) (p < 0.05), total antioxidant capacity (TAC) (p < 0.001), and cellular apoptosis, and decreased levels of superoxide dismutase (SOD), catalase (CAT) (p < 0.01), myotube glycogen content (p < 0.05), glucose transporter type 4 (Glut-4), and cellular viability (p < 0.001). Myricitrin administration improved SOD (p < 0.05), CAT (p < 0.01), muscle cell's glycogen content (p < 0.01), Glut-4 gene expression (p < 0.001), Thiazolyl blue tetrazolium bromide (MTT) (p < 0.05), and Bax to Bcl-2 ratio (p < 0.001), and reduced MDA (p < 0.05) compared to hyperglycemia group. In conclusion, hyperglycemic condition induced oxidative stress along with cellular apoptosis, and myricitrin improved these disorders. Also, low and moderate doses of myricitrin are more efficient on skeletal muscle cells exposed to hyperglycemic statues than a high concentration of this antioxidant agent.

Serum melatonin levels are associated with mortality in patients with malignant middle cerebral artery infarction

Objectives Lower serum melatonin levels are found in patients with ischaemic stroke compared with healthy controls. This study aimed to determine whether serum melatonin levels are associated with peroxidation status, antioxidant status, and mortality in patients with ischaemic stroke. Methods Patients with severe malignant middle cerebral artery infarction (MMCAI), defined as a Glasgow coma scale (GCS) score lower than 9, were included. Serum levels of melatonin, malondialdehyde (to assess lipid peroxidation), and total antioxidant capacity at the time of diagnosing MMCAI were determined. We chose 30-day mortality as the endpoint of the study. Results We found significantly higher serum levels of melatonin, total antioxidant capacity, and malondialdehyde in non-survivors (n = 32) than in survivors (n = 32) with MMCAI. Serum melatonin levels were associated with 30-day mortality (odds ratio = 2.205; 95% confidence interval = 1.294-3.759) after controlling for GCS score and age. We found a positive association between serum melatonin levels and total antioxidant capacity (rho = 0.36), and between serum melatonin and malondialdehyde levels (rho = 0.35). Conclusions Our study shows that serum melatonin levels are associated with peroxidation status, antioxidant status, and mortality in patients with MMCAI.

Solid Lipid Nanoparticles of Myricitrin Have Antioxidant and Antidiabetic Effects on Streptozotocin-Nicotinamide-Induced Diabetic Model and Myotube Cell of Male Mouse

Type 2 diabetes mellitus (T2DM) may occur via oxidative stress. Myricitrin is a plant-derived antioxidant, and its solid lipid nanoparticle (SLN) may be more potent. Hence, the present study was conducted to evaluate the effects of myricitrin SLN on streptozotocin-nicotinamide- (STZ-NA-) induced T2DM of the mouse and hyperglycemic myotube. In this experimental study, cold homogenization method was used to prepare SLN. Then, 120 adult male NMRI mice were divided into 7 groups: control, vehicle, diabetes (received STZ 65 mg/kg 15 min after injected NA 120 mg/kg), diabetes + SLN containing myricitrin 1, 3, and 10 mg/kg, and diabetes + metformin. For in vitro study, myoblast (C2C12) cell line was cultured and divided into 6 groups (n = 3): control, hyperglycemia, hyperglycemia + SLN containing myricitrin 1, 3, and, 10 μM, and hyperglycemia + metformin. After the last nanoparticle treatment, plasma samples, pancreas and muscle tissues, and myotubes were taken for experimental assessments. Diabetes increased lipid peroxidation and reduced antioxidant defense along with the hyperglycemia, insulin resistance, and pancreas apoptosis. Hyperglycemia induced oxidative stress, antioxidant impairment, and cellular apoptosis. Myricitrin SLN improved diabetes and hyperglycemia complications in the in vivo and in vitro studies. Therefore, SLN of myricitrin showed antioxidant, antidiabetic, and antiapoptotic effects in the mouse and myotube cells.

Malondialdehyde: A novel predictive biomarker for post-stroke depression

BACKGROUND

There is evidence that stroke is accompanied by oxidative stress. However, the links between oxidative stress and depression in stroke patients are poorly understood. This study examines whether post-stroke depression (PSD) is associated with oxidative stress.

METHODS

Overall, 216 acute stroke patients were consecutively recruited and followed up for 1 month. Blood specimens were collected within 24h after admission and measured for the following oxidative stress biomarkers: malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX). All enrolled patients were divided into the PSD group or the non-PSD group according to an assessment of clinical depression. One hundred normal control subjects were also recruited.

RESULTS

There was a positive correlation between serum MDA levels and HAMD scores in stroke patients (r=0.536, p<0.001). Based on the Receiver-operating characteristic (ROC) curve, the optimal cutoff value of serum MDA levels as an indicator for an auxiliary diagnosis of PSD was projected to be 2.898 nmol/ml, which yielded a sensitivity of 77.9% and a specificity of 81.1%, with an area under the curve of 0.883 (95% CI, 0.836-0.929). Elevated MDA (≥2.898 nmol/ml) was an independent predictive marker of PSD (odds ratio OR=24.295; 95% CI, 9.461-62.388; p<0.001, adjusted for relevant confounders).

LIMITATIONS

We excluded patients with severe aphasia or with serious conditions. In addition, the information for dietary intake was not recorded, which may influence oxidative stress levels.

CONCLUSION

Our study demonstrated that an elevated serum MDA level at admission was positively associated with an increased risk of developing depression after acute stroke, especially minor stroke.

High Serum Levels of Malondialdehyde and 8-OHdG are both Associated with Early Cognitive Impairment in Patients with Acute Ischaemic Stroke

Post-stroke cognitive impairment (PSCI) is an increasingly prevalent sequel after stroke that may associate with poor functional outcome and increased risk of recurrent stroke. We aimed to explore the relationship between oxidative stress biomarkers and the presence of PSCI. 193 first-ever acute ischaemic stroke patients were consecutively enrolled in the current study. The oxidative stress biomarkers malondialdehyde (MDA) and 8-hydroxydeoxyquanosine (8-OHdG) were measured within 24 h after admission. Cognition function was evaluated by the Mini-Mental State Examination (MMSE) at 1 month after stroke. Serum levels of 8-OHdG and MDA were both significantly higher in the PSCI (p < 0.001) compared with the non-PSCI group. Both the serum levels of both 8-OHdG and MDA were negatively correlated with the MMSE score. Receiver operating characteristic curve analysis was used to evaluate 8-OHdG and MDA as markers of a high risk of PSCI and produced area under curve values of 0.700 and 0.793. Adjusted logistic regression showed that serum 8-OHdG and MDA levels remained as independent markers of PSCI. High serum levels of malondialdehyde and 8-OHdG are associated with the presence of PSCI at 1 month after stroke.

Pre-treatment with spermine for acute cerebral ischemia/reperfusion injuries

Acute cerebral ischemia/reperfusion injury (ACIR) rat model was used to investigate the effect of spermine on oxidative stress and apoptosis. Sixty healthy and clean male Sprague-Dawley rats were randomly divided into 3 groups: The sham-operated group (n=12), the model group (n=12) and the experiment group (n=36). The experiment group was further divided into 3 subgroups: The SPE-10 group (n=12), the SPE-25 group (n=12) and the SPE-50 group (n=12). Rats in the experimental sub-groups SPE-10, SPE-25 and SPE-50 were injected with 10, 25 and 50 mg/kg of spermine, respectively, one week before the establishment of rat models. Rats in the sham-operated and model groups were injected with 0.9% NaCl solution. We evaluated the effect of spermine on malondialdehyde (MDA) level and superoxide dismutase (SOD) activity using ELISA kits. Bax and Bcl-2 levels were measured using western blot analysis. Our results showed that after spermine injection, MDA levels markedly decreased, while SOD activity increased significantly. The variations in MDA levels and SOD activity were dose (spermine)-dependent. Bax protein levels increased significantly, while Bcl-2 levels decreased significantly after the onset of ACIR injuries. After spermine injection, there was a significant decrease in Bax levels. Bcl-2 levels in these rats markedly increased. The observed decline in Bax levels and the increase in Bcl-2 levels in the experimental groups were dose-dependent. We concluded that spermine protected nerve tissues in rats with ACIR by decreasing the MDA level, increasing SOD activity and modifying the balance between Bax and Bcl-2 proteins.

Serum Levels of Substance P and Mortality in Patients with a Severe Acute Ischemic Stroke

Substance P (SP), a member of tachykinin family, is involved in the inflammation of the central nervous system and in the appearance of cerebral edema. Higher serum levels of SP have been found in 18 patients with cerebral ischemia compared with healthy controls. The aim of our multi-center study was to analyze the possible association between serum levels of SP and mortality in ischemic stroke patients. We included patients with malignant middle cerebral artery infarction (MMCAI) and a Glasgow Coma Scale (GCS) lower than 9. Non-surviving patients at 30 days (n = 31) had higher serum concentrations of SP levels at diagnosis of severe MMCAI than survivors (n = 30) (p < 0.001). We found in multiple regression an association between serum concentrations of SP higher than 362 pg/mL and mortality at 30 days (Odds Ratio = 5.33; 95% confidence interval = 1.541-18.470; p = 0.008) after controlling for age and GCS. Thus, the major novel finding of our study was the association between serum levels of SP and mortality in patients suffering from severe acute ischemic stroke.

Serum Levels of Substance P and Mortality in Patients with a Severe Acute Ischemic Stroke

Substance P (SP), a member of tachykinin family, is involved in the inflammation of the central nervous system and in the appearance of cerebral edema. Higher serum levels of SP have been found in 18 patients with cerebral ischemia compared with healthy controls. The aim of our multi-center study was to analyze the possible association between serum levels of SP and mortality in ischemic stroke patients. We included patients with malignant middle cerebral artery infarction (MMCAI) and a Glasgow Coma Scale (GCS) lower than 9. Non-surviving patients at 30 days (n = 31) had higher serum concentrations of SP levels at diagnosis of severe MMCAI than survivors (n = 30) (p < 0.001). We found in multiple regression an association between serum concentrations of SP higher than 362 pg/mL and mortality at 30 days (Odds Ratio = 5.33; 95% confidence interval = 1.541-18.470; p = 0.008) after controlling for age and GCS. Thus, the major novel finding of our study was the association between serum levels of SP and mortality in patients suffering from severe acute ischemic stroke.