Urolithin B Attenuates Cerebral Ischemia-reperfusion Injury by Modulating Nrf2-regulated Anti-oxidation in Rats

Ischemia-reperfusion (IR) induces a wide range of irreversible injuries. Cerebral IR injury (IRI) refers to additional brain tissue damage that occurs after blood flow is restored following cerebral ischemia. Currently, no established methods exist for treating IRI. Oxidative stress is recognized as a primary mechanism initiating IRI and a crucial focal target for its treatment. Urolithin B, a metabolite derived from ellagitannins, antioxidant polyphenols, has demonstrated protective effects against oxidative stress in various disease conditions. However, the precise mechanism underlying UB's effect on IRI remains unclear. In our current investigation, we assessed UB's ability to mitigate neurological functional impairment induced by IR using a neurological deficit score. Additionally, we examined cerebral infarction following UB administration through TTC staining and neuron Nissl staining. UB's inhibition of neuronal apoptosis was demonstrated through the TUNEL assay and Caspase-3 measurement. Additionally, we examined UB's effect on oxidative stress levels by analyzing malondialdehyde (MDA) concentration, superoxide dismutase (SOD) activity, and immunohistochemistry analysis of inducible nitric oxide synthase (iNOS) and 8-hydroxyl-2'-deoxyguanosine (8-OHdG). Notably, UB demonstrated a reduction in oxidative stress levels. Mechanistically, UB was found to stimulate the Nrf2/HO-1 signaling pathway, as evidenced by the significant reduction in UB's neuroprotective effects upon administration of ATRA, an Nrf2 inhibitor. In summary, UB effectively inhibits oxidative stress induced by IR through the activation of the Nrf2/HO-1 signaling pathway. These findings suggest that UB holds promise as a therapeutic agent for the treatment of IRI.

Application of Trace Biological Evidence Collection Kit in DNA Examination of Trace Bloodstain Samples from the Scene

Objective To evaluate the effects of DNA examination of trace bloodstain samples from the scene collected with Trace Biological Evidence Collection kit. Methods Venous blood was made into bloodstains on the ground. The trace bloodstain samples were collected with Trace Biological Evidence Collection kit and common methods, respectively. DNA examination of trace bloodstain samples （50 from each group） was conducted on the constant temperature shaker for 2, 24, 48, 72, and 96 h, respectively, and the examination results of every group were compared. Results When the trace bloodstain samples were placed on the constant temperature shaker for 24, 48, 72, and 96 h, the DNA detection rates in the group which used Trace Biological Evidence Collection kit （100.00%, 100.00%, 100.00%, 96.00%） were significantly higher than those in the group using common methods （62.00%, 26.00%, 10.00%, 0）, the differences had statistical significance （P<0.05）. When the trace bloodstain samples were placed on the constant temperature shaker for 2 h, the differences of DNA detection rates between the two groups had no statistical significance （ P>0.05）. Conclusion The Trace Biological Evidence Collection kit can effectively improve DNA detection rate and extend detection time limit for trace bloodstain samples from the scene that have been stored for a relatively long time.

Utility of serum macrophage migration inhibitory factor as a potential biomarker for detection of cerebrocardiac syndrome following severe traumatic brain injury

BACKGROUND

Cerebrocardiac syndrome (CCS) is a common complication after severe traumatic brain injury (sTBI) and its occurrence obviously increases the risk of a poor outcome. Macrophage migration inhibitory factor (MIF) acts as an inflammatory cytokine and its circulating concentration are related to acute heart and brain injury. The aim of this study was to examine the association of serum concentration of MIF with posttraumatic CCS.

METHODS

From January 2016 to February 2019, 116 sTBI patients and 116 healthy controls with similar age and gender percentage were recruited. Relationship between serum MIF concentration and CCS was assessed using multivariate analysis.

RESULTS

Serum MIF concentration of patients were significantly higher than those among controls. Serum MIF concentration were intimately correlated with Glasgow coma scale scores (t = -5.553, P < 0.001) and serum C-reactive protein concentration (t = 5.320, P < 0.001) in a multivariate linear regression model. 61 patients (52.6%) displayed CCS. Under ROC curve analylsis, there was a strong discriminatory ability for CCS regarding serum MIF concentration (area under curve, 0.834; 95% confidence interval, 0.754-0.897). Serum MIF concentration were highly associated with CCS independent of other confounding factors (odds ratio, 5.608; 95% CI: 1.896-16.587).

CONCLUSIONS

Increased MIF in serum may be a useful biomarker for early detection of CCS after head trauma.

Serum soluble lectin-like oxidized low-density lipoprotein receptor-1 as a biomarker of delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage

OBJECTIVE

Delayed cerebral ischemia (DCI) greatly contributes to the high morbidity and mortality of aneurysmal subarachnoid hemorrhage (aSAH) patients. Expression of lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) was substantially raised in the basilar arterial wall of SAH rabbits. We attempted to ascertain the relationship between serum soluble LOX-1 (sLOX-1) levels and the occurrence of DCI after aSAH.

MATERIALS AND METHODS

We enrolled 125 aSAH patients and 125 healthy controls. Serum sLOX-1 levels were quantified using commercial enzyme-linked immunosorbent assay kit. The relationship between sLOX-1 levels and DCI was analyzed utilizing the multivariate logistic regression analysis.

RESULTS

Serum sLOX-1 levels were significantly higher in stroke patients than in controls (median: 1,450.2 vs. 445.7 pg/ml, p < .001). Serum sLOX-1 levels were highly correlated with World Federation of Neurological Surgeons (WFNS) scores, Hunt-Hess scores, and modified Fisher scores (r = .574, .625, and .569, respectively). Forty-two patients (33.6%) experienced DCI. Serum sLOX-1 > 1,450.2 pg/ml, WFNS scores and modified Fisher scores were the independent predictors of DCI. Under receiver operating characteristic curve, serum sLOX-1 levels exhibited a significant discriminatory capability (area under curve 0.825, 95% confidence interval 0.747-0.887). The predictive power of serum sLOX-1 levels was similar to those of WFNS scores and modified Fisher grade (both p > .05). Moreover, serum sLOX-1 levels significantly improved their predictive capability (both p < .05).

CONCLUSIONS

Serum soluble LOX-1, in positive association with hemorrhagic severity, appears to have the potential to become a promising predictor of DCI after aSAH.

[Effect of Benzidine Test on DNA Analysis of Bloodstain]

OBJECTIVES

To explore the effect of benzidine test and related reagents on DNA analysis of bloodstain.

METHODS

A total of 970 bloodstain filter paper samples with 1 μL venous blood were collected, and 10 of them acted as control samples. After benzidine test and related reagent processing, DNA of 960 samples was extracted by Chelex-100 and silica bead methods and then multiplex amplified by AmpFℓSTR™ Identifiler™ Plus PCR kits. The results of STR typing were compared between different groups.

RESULTS

DNA were extracted immediately after benzidine test. Totally STR loci （3.80±1.34） were detected by silica bead method, while no STR loci were obtained by Chelex-100 method. Thirteen samples （21.7%） with whole STR typing results were obtained by drying after benzidine test, and the STR locus number （12.90±1.49） which obtained by silica bead method was much higher than by Chelex-100 method （4.70±1.96） （P<0.05）. When DNA was extracted immediately after the addition of glacial acetic acid, the STR locus number was （9.40±2.09） by silica bead method, but no STR typing result was obtained by Chelex-100 method. All 15 STR loci could be obtained by only adding glacial acetic acid after drying and only adding tetramethylbenzidine alcoholization liquid or 3% hydrogen peroxide liquid.

CONCLUSIONS

Benzidine test has significant influence on DNA analysis of bloodstain. The Chelex-100 method is not suitable for the DNA extraction of bloodstain after benzidine test. Drying after benzidine test and silica bead methods can effectively enhance the STR locus number of bloodstain.

Macrophage migration inhibitory factor levels in serum from patients with acute intracerebral hemorrhage: Potential contribution to prognosis

BACKGROUND

Intracerebral hemorrhage (ICH) pathophysiology involves inflammation. Macrophage migration inhibition factor (MIF), a pro-inflammatory cytokine, is related to prognosis of ischemic stroke. The aim of this study was to investigate whether serum MIF levels are associated with severity and outcomes in patients with acute ICH.

METHODS

We enrolled a total of 120 consecutive ICH patients and 120 healthy controls and sampled blood on admission and at study entry respectively. Enzyme-linked immunosorbent assay was used to quantify serum MIF levels.

RESULTS

Serum MIF levels were higher in patients compared with controls and correlated with hematoma volume, National Institutes of Health Stroke Scale (NIHSS) scores and plasma C-reactive protein levels. After adjusting for other significant outcome predictors, MIF in serum was an independent predictor of 6-month overall survival and unfavorable outcome (modified Rankin Scale score >2). Areas under receiver-operating characteristic curve (ROC) of serum MIF levels, hematoma volume and NIHSS scores were similar for 6-month unfavorable outcome. Moreover, serum MIF levels significantly improved areas under ROC of hematoma volume and NIHSS scores.

CONCLUSIONS

MIF in serum might be a potential biomarker for reflecting inflammation, severity and prognosis of ICH patients.

Thioredoxin as a marker for severity and prognosis of aneurysmal subarachnoid hemorrhage

OBJECTIVE

Circulating levels of thioredoxin (Trx), a potent anti-oxidant that modulates inflammation, cell growth and apoptosis, are increased in various critical care conditions. The purpose of this study was to establish the relationship between serum Trx levels and prognosis of aneurysmal subarachnoid hemorrhage (aSAH).

METHODS

An enzyme-linked immunosorbent assay measurement of Trx was performed in serum from 132 patients and 132 healthy volunteers. Clinical outcomes included 6-month mortality and unfavorable outcome (Glasgow outcome scale score of 1-3).

RESULTS

The serum Trx levels were significantly higher in patients than in controls (23.4±12.2 ng/mL vs.8.5±4.0 ng/mL, P<0.001) and had close relation to the World Federation of Neurological Surgeons (WFNS) scores (r=0.461, P<0.001) and modified Fisher scores (r=0.459, P<0.001). Trx was an independent predictor for 6-month mortality (Odds ratio, 1.386; 95% confidence interval, 1.015-2.161; P<0.001) and 6-month unfavorable outcome (Odds ratio, 1.297; 95% confidence interval, 1.012-2.002; P<0.001). Based on receiver operating characteristic curve, TRX had similar prognostic value compared with WFNS scores and modified Fisher scores and also significantly improved their prognostic value for 6-month unfavorable outcome, but not for 6-month mortality.

CONCLUSIONS

Elevated plasma Trx levels are correlated with the severity and poor prognosis, substantializing Trx as a potential prognostic predictive biomarker following aSAH.

Identification of plasma adrenomedullin as a possible prognostic biomarker for aneurysmal subarachnoid hemorrhage

Increased plasma adrenomedullin levels have been reported in critically ill patients. This study tested the hypothesis that plasma adrenomedullin levels are significantly increased in patients with acute spontaneous aneurysmal subarachnoid hemorrhage, and are predictive of clinical outcomes. Plasma adrenomedullin levels from 120 adult patients with spontaneous aneurysmal subarachnoid hemorrhage and 120 healthy volunteers during the study period were evaluated. Mortality and poor long-term outcome (Glasgow Outcome Scale score of 1-3) at 6 months were recorded. Data showed that circulating plasma adrenomedullin levels significantly increased in patients on admission compared with the volunteers. In patients who died or had poor outcome at 6 months, plasma adrenomedullin levels were significantly higher compared with survivors and patients with good outcome. Plasma adrenomedullin levels on presentation were highly associated with clinical severity assessed using World Federation of Neurological Surgeons score and Fisher score, emerged as the independent risk factor of 6-month mortality and poor outcome, and possessed similar predictive value to World Federation of Neurological Surgeons score and Fisher score based on receiver operating characteristic curves. A combined logistic-regression model did not demonstrate the additive benefit of adrenomedullin to World Federation of Neurological Surgeons score and Fisher score. Thus, higher plasma adrenomedullin levels on presentation are associated with clinical severity and worse outcomes in patients with acute spontaneous aneurysmal subarachnoid hemorrhage.