1.Sepsis Associated Encephalopathy Accompanied by Bilateral Corticospinal Tract Lesions in Diffusion Weighed Image
Unkyu YUN ; Sang Won HA ; Seung Min KIM ; In Joong KIM
Journal of the Korean Neurological Association 2018;36(2):129-131
No abstract available.
Diffusion
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Leukoencephalopathies
;
Pyramidal Tracts
;
Sepsis
;
Sepsis-Associated Encephalopathy
2.Research Progress in Clinical Electrophysiological Assessment of Patients with Sepsis-Associated Encephalopathy.
Meng-Lu ZHOU ; Guang-Yong JIN ; Shao-Song XI ; Jia-Yi CHEN ; Dong-Cheng LIANG
Acta Academiae Medicinae Sinicae 2022;44(5):876-884
Sepsis-associated encephalopathy(SAE) caused by infections outside the central nervous system always presents extensive brain damage.It is common in clinical practice and associated with a poor prognosis.There are problems in the assessing and diagnosing of SAE.Many factors,such as sedation and mechanical ventilation,make it difficult to assess SAE,while electrophysiological examination may play a role in the assessment.We reviewed the studies of electrophysiological techniques such as electroencephalography and somatosensory evoked potentials for monitoring SAE,hoping to provide certain evidence for the clinical evaluation and diagnosis of SAE.
Humans
;
Sepsis-Associated Encephalopathy/complications*
;
Sepsis/diagnosis*
;
Electroencephalography
3.Autophagy in hippocampal nerve cells from rats with sepsis-associated encephalopathy.
Yafei LI ; Yunjie SU ; Yi QU ; Dezhi MU ; Xihong LI
Journal of Central South University(Medical Sciences) 2016;41(6):571-577
OBJECTIVE:
To show evidence of the autophagy in hippocampal nerve cells from rats with sepsis-associated encephalopathy (SAE) in vivo and to investigate the expression of microtubule-associated protein 1 light chain 3 (LC3).
METHODS:
A rat model of sepsis was established by the cecal ligation and puncture (CLP). A total of 60 male Wistar rats (30 days old) were randomly divided into a sham group (n=10) and a CLP group (n=50). At 12 hours after CLP, the electroencephalogram (EEG) and somatosensory evoked potential (SEP) changes in rats were monitored and the neurobehavioral score was measured. According to the occurrence of SAE, the CLP group was further divided into an SAE(+) group and an SAE(-) group. Histopathological changes in hippocampus were observed by hematoxylin-eosin staining. An electron microscope was used to observe autophagosome formation and lysosome activation in the hippocampal nerve cells. Expressions of LC3-I and LC3-II protein were measured by Western blot.
RESULTS:
Five of 50 rats in CLP group died in 12 hours after CLP. According to the low neurobehavioral score and abnormal EEG and SEP, 16 rats were diagnosed as SAE. The incidence of SAE was 35.56% (16/45). Compared with the sham group or the SAE(-) group, the frequency of α wave in SAE(+) group was significantly decreased at 12 hours after CLP, the δ wave increased, the P1 amplitude decreased, and the latency of SEP waves (P1 and N1) was prolonged (P<0.05). The morphology of hippocampal nerve cells was obvious in a status of edema. Pyramidal cells decreased significantly, even dissolved, and cell arrangement was in disorder in the SAE(+) group. But these cells were normal in the sham group and the SAE(-) group. The structure of hippocampal nerve cells was disordered, and the autophagy, granular matrix and square or rectangular crystals were found in the SAE(+) group. However, there was no autophagy both in the sham group and the SAE(-) group. LC3-II/LC3-I ratio in the hippocampal nerve cells was increased significantly at 12 hours after CLP in the SAE(+) group when compared with that in the sham or the SAE(-) group (P<0.05).
CONCLUSION
There is autophagy in hippocampal nerve cells from rats with SAE and the LC3-II/LC3-I ratio is increased significantly.
Animals
;
Autophagy
;
Hippocampus
;
Male
;
Microtubule-Associated Proteins
;
Neurons
;
Rats
;
Rats, Wistar
;
Sepsis-Associated Encephalopathy
4.Expression level of glial fibrillary acidic protein and its clinical significance in patients with sepsis-associated encephalopathy.
Shanshan YAN ; Min GAO ; Huan CHEN ; Xin JIN ; Mingshi YANG
Journal of Central South University(Medical Sciences) 2019;44(10):1137-1142
To determine expression levels of glial fibrillary acidic protein in patients of sepsis-associated encephalopathy (SAE) and its clinical significance.
Methods: Patients, admitted to intensive care units and diagnosed as sepsis, were recruited to our study from October 2016 to August 2018 in the Third Xiangya Hospital, Central South University. SAE is defined as a brain dysfunction secondary to sepsis and without evidence of a primary central nervous system infection or encephalopathy due to other reasons. The SAE group and non-SAE group were classed by Confusion Assessment Method for the ICU (CAM-ICU) score. We measured the levels of serum GFAP, S100β and neuron-specific enolase (NSE) within 24 hours after diagnosis of sepsis, and compared the patients' general clinical data, ICU stay time, 28-day and 180-day mortality.
Results: Among 152 enrolled patients, 58 and 94 were assigned to the SAE group and the non-SAE group, respectively. There were a significantly higher Sequential Organ Failure Assessment (SOFA) scores, 28-day mortality rate, as well as 180-day mortality rate in the SAE group (all P<0.001). The levels of GFAP, NSE and S100β in the SAE group were significantly higher than those in the non-SAE group (all P<0.001). The diagnostic values of GFAP was 0.67 μg/L, with sensitivity at 75.9% and specificity at 77.7%. Area under the receiver operating characteristic curve (AUROC) of GFAP, NSE and S100β were 0.803, 0.795 and 0.750, respectively. Pearson analysis showed that serum GFAP level was positively correlated with Acute Physiology and Chronic Health Evaluation II (APACHE II) score, but it was negatively correlated with Glasgow Coma Scale (GCS) score, 28-day survival rate and 180-day survival rate.
Conclusion: The level of serum GFAP is significantly increased in SAE, which shows certain correlation with incidence, severity and prognosis of the disease.
APACHE
;
Glial Fibrillary Acidic Protein
;
blood
;
Humans
;
Intensive Care Units
;
Organ Dysfunction Scores
;
Prognosis
;
ROC Curve
;
Sepsis
;
Sepsis-Associated Encephalopathy
;
diagnosis
5.Value of cerebral hypoxic-ischemic injury markers in the early diagnosis of sepsis associated encephalopathy in burn patients with sepsis.
Xiao Liang LI ; Jiang Fan XIE ; Xiang Yang YE ; Yun LI ; Yan Guang LI ; Ke FENG ; She Min TIAN ; Ji He LOU ; Cheng De XIA
Chinese Journal of Burns 2022;38(1):21-28
Objective: To explore the value of cerebral hypoxic-ischemic injury markers in the early diagnosis of sepsis associated encephalopathy (SAE) in burn patients with sepsis. Methods: A retrospective case series study was conducted. From October 2018 to May 2021, 41 burn patients with sepsis who were admitted to Zhengzhou First People's Hospital met the inclusion criteria, including 23 males and 18 females, aged 18-65 (35±3) years. According to whether SAE occurred during hospitalization, the patients were divided into SAE group (21 cases) and non-SAE group (20 cases). The gender, age, deep partial-thickness burn area, full-thickness burn area, and acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) scores of patients were compared between the two groups. The serum levels of central nervous system specific protein S100β and neuron specific enolase (NSE) at 12, 24, and 48 h after sepsis diagnosis (hereinafter referred to as after diagnosis), the serum levels of interleukin-6 (IL-6), IL-10, tumor necrosis factor α (TNF-α), Tau protein, adrenocorticotropic hormone (ACTH), and cortisol at 12, 24, 48, 72, 120, and 168 h after diagnosis, and the mean blood flow velocity of middle cerebral artery (VmMCA), pulsatility index, and cerebral blood flow index (CBFi) on 1, 3, and 7 d after diagnosis of patients in the two groups were counted. Data were statistically analyzed with chi-square test, analysis of variance for repeated measurement, independent sample t test, and Bonferroni correction. The independent variables to predict the occurrence of SAE was screened by multi-factor logistic regression analysis. The receiver operating characteristic (ROC) curve was drawn for predicting the occurrence of SAE in burn patients with sepsis, and the area under the curve (AUC), the best threshold, and the sensitivity and specificity under the best threshold were calculated. Results: The gender, age, deep partial-thickness burn area, full-thickness burn area, and APACHE Ⅱ score of patients in the two groups were all similar (χ2=0.02, with t values of 0.71, 1.59, 0.91, and 1.07, respectively, P>0.05). At 12, 24, and 48 h after diagnosis, the serum levels of S100β and NSE of patients in SAE group were all significantly higher than those in non-SAE group (with t values of 37.74, 77.84, 44.16, 22.51, 38.76, and 29.31, respectively, P<0.01). At 12, 24, 48, 72, 120, and 168 h after diagnosis, the serum levels of IL-10, Tau protein, and ACTH of patients in SAE group were all significantly higher than those in non-SAE group (with t values of 10.68, 13.50, 10.59, 8.09, 7.17, 4.71, 5.51, 3.20, 3.61, 3.58, 3.28, 4.21, 5.91, 5.66, 4.98, 4.69, 4.78, and 2.97, respectively, P<0.01). At 12, 24, 48, 72, and 120 h after diagnosis, the serum levels of IL-6 and TNF-α of patients in SAE group were all significantly higher than those in non-SAE group (with t values of 8.56, 7.32, 2.08, 2.53, 3.37, 4.44, 5.36, 5.35, 6.85, and 5.15, respectively, P<0.05 or P<0.01). At 12, 24, and 48 h after diagnosis, the serum level of cortisol of patients in SAE group was significantly higher than that in non-SAE group (with t values of 5.44, 5.46, and 3.55, respectively, P<0.01). On 1 d after diagnosis, the VmMCA and CBFi of patients in SAE group were significantly lower than those in non-SAE group (with t values of 2.94 and 2.67, respectively, P<0.05). On 1, 3, and 7 d after diagnosis, the pulsatile index of patients in SAE group was significantly higher than that in non-SAE group (with t values of 2.56, 3.20, and 3.12, respectively, P<0.05 or P<0.01). Serum IL-6 at 12 h after diagnosis, serum Tau protein at 24 h after diagnosis, serum ACTH at 24 h after diagnosis, and serum cortisol at 24 h after diagnosis were the independent risk factors for SAE complicated in burn patients with sepsis (with odds ratios of 2.42, 1.38, 4.29, and 4.19, 95% confidence interval of 1.76-3.82, 1.06-2.45, 1.37-6.68, and 3.32-8.79, respectively, P<0.01). For 41 burn patients with sepsis, the AUC of ROC of serum IL-6 at 12 h after diagnosis for predicting SAE was 0.92 (95% confidence interval was 0.84-1.00), the best threshold was 157 pg/mL, the sensitivity was 81%, and the specificity was 89%. The AUC of ROC of serum Tau protein at 24 h after diagnosis for predicting SAE was 0.92 (95% confidence interval was 0.82-1.00), the best threshold was 6.4 pg/mL, the sensitivity was 97%, and the specificity was 99%. The AUC of ROC of serum ACTH at 24 h after diagnosis for predicting SAE was 0.96 (95% confidence interval was 0.89-1.00), the best threshold was 14.7 pg/mL, the sensitivity was 90%, and the specificity was 94%. The AUC of ROC of serum cortisol at 24 h after diagnosis for predicting SAE was 0.93 (95% confidence interval was 0.86-1.00), the best threshold was 89 nmol/L, the sensitivity was 94%, and the specificity was 97%. Conclusions: Serum Tau protein, ACTH, and cortisol have high clinical diagnostic value for SAE complicated in burn patients with sepsis.
Adolescent
;
Adult
;
Aged
;
Burns/complications*
;
Early Diagnosis
;
Female
;
Humans
;
Male
;
Middle Aged
;
Prognosis
;
ROC Curve
;
Retrospective Studies
;
Sepsis/diagnosis*
;
Sepsis-Associated Encephalopathy
;
Young Adult
6.Phosphate and tension homology-induced kinase 1/Parkin signaling mediates cognitive dysfunction in sepsis-associated encephalopathy through activation of hippocampal mitochondrial autophagy.
Yue FENG ; Yuqi DAI ; Yaoyi GUO ; Fan JIANG ; Hongsen LIAO ; Haojia LI ; Hongguang BAO ; Yanna SI
Chinese Critical Care Medicine 2023;35(4):381-386
OBJECTIVE:
To investigate the effects of gene of phosphate and tension homology (PTEN)-induced putative kinase 1 (PINK1)/Parkin pathway on hippocampal mitophagy and cognitive function in mice with sepsis-associated encephalopathy (SAE) and its possible mechanism.
METHODS:
A total of 80 male C57BL/6J mice were randomly divided into Sham group, cecal ligation puncture (CLP) group, PINK1 plasmid transfection pretreatment groups (p-PINK1+Sham group, p-PINK1+CLP group), empty vector plasmid transfection control group (p-vector+CLP group), with 16 mice in each group. The mice in CLP groups were treated with CLP to reproduce SAE models. The mice in the Sham groups were performed laparotomy only. Animals in the p-PINK1+Sham and p-PINK1+CLP groups were transfected with PINK1 plasmid through the lateral ventricle at 24 hours before surgery, while mice in the p-vector+CLP group were transfected with the empty plasmid. Morris water maze experiment was performed 7 days after CLP. The hippocampal tissues were collected, the pathological changes were observed under a light microscope after hematoxylin-eosin (HE) staining, and the mitochondrial autophagy was observed under a transmission electron microscopy after uranyl acetate and lead citrate staining. The expressions of PINK1, Parkin, Beclin1, interleukins (IL-6, IL-1β) and microtubule-associated protein 1 light chain 3 (LC3) were detected by Western blotting.
RESULTS:
Compared with the Sham group, CLP group mice in Morris water maze experiment had longer escape latency, shorter target quadrant residence time, and fewer times of crossing the platform at 1-4 days. Under the light microscope, the hippocampal structure of the mouse was injured, the neuronal cells were arranged in disorder, and the nuclei were pyknotic. Under the electron microscope, the mitochondria appeared swollen, round, and wrapped by bilayer or multilayer membrane structures. Compared with the Sham group, CLP group had higher expressions of PINK1, Parkin, Beclin1, LC3II/LC3I ratio, IL-6 and IL-1β in hippocampus, indicating that sepsis induced by CLP could activated inflammatory response and caused PINK1/Parkin-mediated mitophagy. Compared with the CLP group, p-PINK1+CLP group had shorter escape latencies, spent more time in the target quadrant and had more number of crossings in the target quadrant at 1-4 days. Under the light microscope, the hippocampal structures of mice was destroyed, the neurons were arranged disorderly, and the nuclei were pyknotic. Under transmission electron microscope, swollen and rounded mitochondria and mitochondrial structure wrapped by double membrane or multilayer membrane structure were observed. Compared with the CLP group, the levels of PINK1, Parkin, Beclin1 and LC3II/LC3 ratio in the p-PINK1+CLP group were significantly increased [PINK1 protein (PINK1/β-actin): 1.95±0.17 vs. 1.74±0.15, Parkin protein (Parkin/β-actin): 2.06±0.11 vs. 1.78±0.12, Beclin1 protein (Beclin1/β-actin): 2.11±0.12 vs. 1.67±0.10, LC3II/LC3I ratio: 3.63±0.12 vs. 2.27±0.10, all P < 0.05], while the levels of IL-6 and IL-1β were significantly decreased [IL-6 protein (IL-6/β-actin): 1.69±0.09 vs. 2.00±0.11, IL-1β protein (IL-1β/β-actin): 1.11±0.12 vs. 1.65±0.12, both P < 0.05], suggesting that overexpression of PINK1 protein could further activate mitophagy and reduce the inflammatory response caused by sepsis. There was no statistically significant difference in the above pathological changes and related indicators between Sham group and p-PINK1+Sham group, CLP group and p-vector+CLP group.
CONCLUSIONS
PINK1 overexpression can further activate CLP-induced mitophagy by upregulating Parkin, thereby inhibiting inflammation response and alleviate cognitive function impairment in SAE mice.
Male
;
Animals
;
Mice
;
Mice, Inbred C57BL
;
Sepsis-Associated Encephalopathy
;
Phosphates
;
Actins
;
Beclin-1
;
Interleukin-6
;
Autophagy
;
Ubiquitin-Protein Ligases
;
Cognitive Dysfunction
;
Sepsis
;
Mitochondria
;
Protein Kinases
7.Hippocampal neuronal ferroptosis involved in cognitive dysfunction in rats with sepsis-related encephalopathy through the Nrf2/GPX4 signaling pathway.
Peng YAO ; Yong CHEN ; Yiling LI ; Yuzi ZHANG ; Hao QI ; Wenhao XU
Chinese Critical Care Medicine 2019;31(11):1389-1394
OBJECTIVE:
To evaluate the effects of ferroptosis in hippocampal neurons on cognitive dysfunction in rats with sepsis-associated encephalopathy (SAE) and its potential molecular mechanisms.
METHODS:
(1) Screening experiment of SAE modeling conditions: 42 healthy male Sprague-Dawley (SD) rats were divided into normal saline (NS) control group (n = 6) and lipopolysaccharide (LPS) 5, 15, 30 mg/kg groups (each n = 12) according to the random number table method. The SAE modeling conditions were determined by survival and the changes in mean arterial pressure (MAP) and heart rate (HR) within 72 hours, the percentage of stiffness status, the levels of serum inflammatory factors including interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), neuron specific enolase (NSE, a marker of neuronal injury), serum iron and lactic acid (Lac) contents, and the morphological changes in CA1 of hippocampus after 72 hours. (2) Deferoxamine (Def) intervention experiment: according to the results of screening experiments, 28 healthy male SD rats were divided into NS control group (n = 8), SAE group (n = 10) and Def+SAE group (n = 10) according to the random number table method. In the Def+SAE group, 100 mg/kg Def was injected intraperitoneally 12 hours before the modeling, once every 12 hours, with a total of 7 times; the rats in the NS control group and SAE group were injected with the same amount of NS. Then the cognitive function of rats was evaluated by fear conditioning test for the percentage of stiffness status; serum IL-6, TNF-α and NSE levels were determined by enzyme-linked immunosorbent assay (ELISA); the levels of serum Lac, serum iron and hippocampal malondialdehyde (MDA) and iron contents were determined by chemical colorimetric; the protein expressions of nuclear factor E2 related factor 2 (Nrf2), glutathione peroxidase 4 (GPX4) and NAPDH oxidase 1 (NOX1) in hippocampus were determined by Western Blot; morphological changes in hippocampal CA1 were observed after hematoxylin and eosin (HE) staining.
RESULTS:
(1) Compared with the NS control group, intraperitoneal injection of 15 mg/kg LPS could significantly reduce the MAP and HR as time prolonged, and the reduction was most significant at 72 hours. The 72-hour survival rate was significantly reduced and cognitive function was impaired. The levels of serum IL-6, TNF-α, Lac and NSE were increased while the serum iron content was decreased significantly. The morphology of vertebral cells in hippocampal CA1 was irregular and some of the cells were obviously vacuolated. In the LPS 5 mg/kg group, there were no significant changes in vital signs, inflammation, organ function or cognitive dysfunction, while the symptoms of septic shock were apparent in the LPS 30 mg/kg group. Therefore, SAE model was reproduced by intraperitoneal injection of 15 mg/kg LPS for 72 hours. (2) Compared with the NS control group, the percentage of stiffness in the SAE group was significantly reduced. The levels of serum IL-6, NSE and hippocampal MDA, iron were significantly increased. The serum iron contents and hippocampal Nrf2 and GPX4 protein expressions were significantly reduced, while the hippocampal NOX1 protein expression was significantly increased. The morphology of vertebral cells in hippocampal CA1 was irregular and the cytoplasm was deeply stained. The results indicated that the level of oxidative stress in the hippocampus of SAE rats was increased, the neuron degenerations were obvious, and the cognitive function of rats were impaired. Compared with the SAE group, the percentage of stiffness in the Def+SAE group was significantly increased [(63.4±6.4)% vs. (47.6±6.0)%, P < 0.05]. The levels of serum IL-6, NSE, iron and hippocampal MDA, iron were significantly reduced [serum IL-6 (ng/L): 73.14±8.31 vs. 99.86±12.37, serum NSE (μg/L): 3.67±0.51 vs. 5.92±0.79, serum iron (mg/L): 68.43±8.12 vs. 134.60±15.63, hippocampal MDA (mol/g): 4.62±0.90 vs. 6.62±0.84, hippocampal iron (μg/g): 155.32±17.86 vs. 221.54±27.54, all P < 0.05]. The hippocampal protein expressions of Nrf2 and GPX4 were significantly increased [Nrf2/β-actin: 0.41±0.07 vs. 0.18±0.03, GPX4/β-actin: 0.74±0.09 vs. 0.40±0.06, all P < 0.05] while the hippocampal NOX1 protein expression was significantly reduced (NOX1/β-actin: 0.62±0.08 vs. 1.11±0.16, P < 0.05). The vertebral cells was significantly improved as compared with the SAE group. These findings showed that the oxidative stress level in hippocampus of the Def+SAE group was reduced, neuron degeneration was significantly alleviated, and the cognitive function of the rats was significantly improved.
CONCLUSIONS
The cognitive function of rats with SAE was significantly impaired, the hippocampal neurons were obviously damaged and ferroptosis was increased. Def pretreatment could significantly reduce iron deposition and ferroptosis in hippocampal neurons of SAE rats and improve cognitive dysfunction, which may be related to activation of Nrf2/GPX4 signaling pathway.
Animals
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Cognitive Dysfunction
;
Ferroptosis
;
Hippocampus
;
Male
;
NF-E2-Related Factor 2/metabolism*
;
Neurons
;
Rats
;
Rats, Sprague-Dawley
;
Sepsis
;
Sepsis-Associated Encephalopathy
;
Signal Transduction
;
Tumor Necrosis Factor-alpha
8.Treatment of Sepsis-associated Encephalopathy by Xingnaojing Injection: a Clinical Observation.
Su LV ; Jia LI ; Bao-ping CAO ; Ji-hong ZHU
Chinese Journal of Integrated Traditional and Western Medicine 2015;35(7):792-795
OBJECTIVETo observe the efficacy of Xingnaojing Injection (XI) in treatment of sepsis-associated encephalopathy (SAE).
METHODSTotally 65 SAE patients were retrospectively analyzed at EICU from September 2010 to September 2013. They were assigned to the control group (32 cases) and the treatment group (33 cases) according to whether they received XI. Patients in the control group received anti-infection and symptomatic support, while those in the treatment group were intravenously injected with XI at 20 mL per day for additional 7-10 days. The fever clearance time, Glasgow coma scale (GCS), C-reactive protein (CRP), neuron-specific enolase (NSE), and improvement of electroen-cephalogram (EEG) were observed in the two groups.
RESULTSCompared with the control group, the fever clearance time was shortened, CRP levels decreased, GCS score and efficacy of EEG was alleviated in the treatment group after treatment with statistical difference (P < 0.05). No adverse reaction occurred during medication.
CONCLUSIONX1 was safe and effective in treatment of SAE.
C-Reactive Protein ; metabolism ; Drugs, Chinese Herbal ; administration & dosage ; therapeutic use ; Humans ; Injections ; Phosphopyruvate Hydratase ; metabolism ; Sepsis-Associated Encephalopathy ; drug therapy ; Treatment Outcome
9.Mechanism of myeloid differentiation factor 2 on mediating sepsis-associated encephalopathy.
Qi JIA ; Tingting GU ; Yi LI ; Jiawei WANG ; Jin LI ; Zongping FANG ; Xijing ZHANG
Chinese Critical Care Medicine 2023;35(11):1200-1206
OBJECTIVE:
To investigate the role and underlying mechanism of human myeloid differentiation protein 2 (MD2) in the process of neuronal death induced by lipopolysaccharide (LPS) by establishing an in vitro model of sepsis-associated encephalopathy (SAE) by LPS.
METHODS:
Healthy C57BL/6J mice at 14-18 days of gestation were selected, and brain cortical tissue was taken from fetal mice. Neurons were stimulated with 0 (control), 1, 5 and 10 g/L of LPS for 24 hours. The release of lactate dehydrogenase (LDH) was detected and the death of neurons was observed. Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of inflammatory factors interleukins (IL-6, IL-1β), in order to determine the optimal dose of LPS for establishing an in vitro neuroinflammation model of SAE. The cells were divided into blank control group and LPS group. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end-labeling (TUNEL) was used to discover apoptosis. Western blotting was used to detect the expression of the relevant protein markers activated caspase-3, necroptosis-associated protein neuronal receptor-interacting serine/threonine-protein kinase 3 (RIPK3) and phosphorylated RIPK3 (p-RIPK3). Immunofluorescence chemical staining was used to detect the expressions of p-RIPK3 and microtubule-associated protein 2 (MAP2) to evaluate the type of cell death and the degree of neuronal death. Western blotting was used to detect MD2 expression. Immunofluorescence chemical staining was performed to observe the expression and distribution of p-RIPK3 and MD2 in neurons to assess whether MD2 was involved in the inflammatory response promoting neuronal death. In addition, the cells were divided into blank control group, LPS group, and MD2 interfering peptide group (LPS+TC group), and the levels of IL-6, IL-1β and LDH were detected to evaluate whether interfering with MD2 can alleviate LPS induced neuroinflammation.
RESULTS:
10 g/L LPS induced notable neuronal death, and the release of LDH in neurons stimulated with this concentration for 24 hours was significantly higher than that in the blank control group (relative release: 1.45±0.04 vs. 1.00±0.00, P < 0.01), indicating apoptosis and necroptosis occurred in neurons, and the levels of inflammatory factors IL-6 and IL-1β were remarkable increased [IL-6 (relative level): 1.94±0.04 vs. 1.00±0.00, IL-1β (relative level): 1.53±0.09 vs. 1.00±0.00, both P < 0.01]. Compared with the blank control group, the apoptosis of cells, cleaved-caspase-3 expression, the p-RIPK3/RIPK3 ratio, and p-RIPK3 expression around neurons in the LPS group were significantly increased [cleaved-caspase-3/GAPDH: 1.55±0.10 vs. 1.00±0.00, P < 0.01; p-RIPK3/RIPK3 ratio (relative value): 1.54±0.06 vs. 1.00±0.00, P < 0.05], which suggested that typical apoptosis and necroptosis apoptosis occurred in neurons in the septic environment. Furthermore, MD2 expression was significantly increased in the LPS group compared with the blank control group (MD2/GAPDH: 1.91±0.07 vs. 1.00±0.00, P < 0.01), and MD2 expression around neurons was increased, indicating that LPS-induced MD2 upregulation may play a key role in neuroinflammation and induction of neuronal death in sepsis. In addition, compared with the LPS group, the MD2-interfering peptide could reduce the expression levels of inflammatory factors IL-6 and IL-1β [IL-6 (relative level): 1.16±0.08 vs. 1.94±0.04, IL-1β (relative level): 1.15±0.05 vs. 1.75±0.09, both P < 0.01] and decrease LDH release (relative release: 1.09±0.01 vs. 1.44±0.04, P < 0.05).
CONCLUSIONS
LPS induced neuronal inflammatory responses via MD2, which ultimately leads to apoptosis and necroptosis. Interfering with MD2 reduces inflammation and inhibits neuronal death.
Mice
;
Humans
;
Animals
;
Sepsis-Associated Encephalopathy
;
Caspase 3
;
Interleukin-6
;
Neuroinflammatory Diseases
;
Lipopolysaccharides
;
Mice, Inbred C57BL
;
Cell Differentiation
;
Tumor Necrosis Factor-alpha
10.Diagnostic and Predictive Levels of Calcium-binding Protein A8 and Tumor Necrosis Factor Receptor-associated Factor 6 in Sepsis-associated Encephalopathy: A Prospective Observational Study.
Li-Na ZHANG ; Xiao-Hong WANG ; Long WU ; Li HUANG ; Chun-Guang ZHAO ; Qian-Yi PENG ; Yu-Hang AI
Chinese Medical Journal 2016;129(14):1674-1681
BACKGROUNDDespite its high prevalence, morbidity, and mortality, sepsis-associated encephalopathy (SAE) is still poorly understood. The aim of this prospective and observational study was to investigate the clinical significance of calcium-binding protein A8 (S100A8) in serum and tumor necrosis factor receptor-associated factor 6 (TRAF6) in peripheral blood mononuclear cells (PBMCs) in diagnosing SAE and predicting its prognosis.
METHODSData of septic patients were collected within 24 h after Intensive Care Unit admission from July 2014 to March 2015. Healthy medical personnel served as the control group. SAE was defined as cerebral dysfunction in the presence of sepsis that fulfilled the exclusion criteria. The biochemical indicators, Glasgow Coma Scale, Acute Physiology and Chronic Health Evaluation score II, TRAF6 in PBMC, serum S100A8, S100β, and neuron-specific enolase were evaluated in SAE patients afresh. TRAF6 and S100A8 were also measured in the control group.
RESULTSOf the 57 enrolled patients, 29 were diagnosed with SAE. The S100A8 and TRAF6 concentrations in SAE patients were both significantly higher than that in no-encephalopathy (NE) patients, and higher in NE than that in controls (3.74 ± 3.13 vs. 1.08 ± 0.75 vs. 0.37 ± 0.14 ng/ml, P < 0.01; 3.18 ± 1.55 vs. 1.02 ± 0.63 vs. 0.47 ± 0.10, P < 0.01). S100A8 levels of 1.93 ng/ml were diagnostic of SAE with 92.90% specificity and 69.00% sensitivity in the receiver operating characteristic (ROC) curve, and the area under the curve was 0.86 (95% confidence interval [CI]: 0.76-0.95). TRAF6-relative levels of 1.44 were diagnostic of SAE with 85.70% specificity and 86.20% sensitivity, and the area under the curve was 0.94 (95% CI: 0.88-0.99). In addition, S100A8 levels of 2.41 ng/ml predicted 28-day mortality of SAE with 90.00% specificity and 73.70% sensitivity in the ROC curve, and the area under the curve was 0.88. TRAF6 relative levels of 2.94 predicted 28-day mortality of SAE with 80.00% specificity and 68.40% sensitivity, and the area under the curve was 0.77. Compared with TRAF6, the specificity of serum S100A8 in diagnosing SAE and predicting mortality was higher, although the sensitivity was low. In contrast, the TRAF6 had higher sensitivity for diagnosis.
CONCLUSIONSPeripheral blood levels of S100A8 and TRAF6 in SAE patients were elevated and might be related to the severity of SAE and predict the outcome of SAE. The efficacy and specificity of S100A8 for SAE diagnosis were superior, despite its weak sensitivity. S100A8 might be a better biomarker for diagnosis of SAE and predicting prognosis.
Adult ; Aged ; Biomarkers ; blood ; Calgranulin A ; blood ; Calmodulin ; blood ; Female ; Humans ; Male ; Middle Aged ; Prospective Studies ; S100 Calcium Binding Protein beta Subunit ; blood ; Sepsis-Associated Encephalopathy ; blood ; diagnosis ; TNF Receptor-Associated Factor 6 ; blood