1.A profile of out-of-hospital cardiac arrest in Amang Rodriguez Memorial Medical Center: A prospective cohort study
Donna Erika E. De Jesus ; Ken P. Manongas
Philippine Journal of Internal Medicine 2025;63(1):45-50
INTRODUCTION
Cardiac arrest occurs when abrupt cessation of cardiac function results in loss of effective circulation and complete cardiovascular collapse. For every minute of cardiac arrest without early intervention (cardiopulmonary resuscitation [CPR], defibrillation), chances of survival drop by 7 – 10%. It is crucial that CPR be initiated within 4 – 6 minutes to avoid brain death. Most out-of-hospital cardiac arrests (OHCA) occur in a residential setting where access to trained personnel and equipment is not readily available, resulting in poor victim outcomes.
METHODSThis descriptive study was done from August to November 2021 using a prospective cohort design. Participants of the study include adult patients aged 18 years and above brought to the emergency room who suffered from out-ofhospital cardiac arrest. Out of the total 102 cases of OHCA, 63 participants were included in the study. Descriptive statistics was used to summarize the demographic and clinical characteristics of the patients.
RESULTSForty-three subjects were male patients, comprising the majority at 73.02%. Hypertension was identified as the top comorbidity, followed by diabetes mellitus, heart failure, and chronic kidney disease (CKD). Medical causes of arrest were identified in 96.83% of the cases. 90.48% of cardiac arrests occurred at home. Only 26 patients (41.27%) received prehospital intervention before ER arrival, comprising only hands-on CPR. Twenty-three of these were performed by individuals with background knowledge of CPR. 60.32% were brought via self-conduction, the remainder by ambulances, which were noted to have no available equipment necessary to provide proper resuscitation. The average travel time from dispatch to
ER arrival is 20 minutes.
Overall survival of OHCA in our local setting remains dismal, as the return of spontaneous circulation was not achieved in any of the patients. The small number of patients having pre-hospital CPR indicates the need for emphasis on training and community education.
Human ; Out-of-hospital Cardiac Arrest ; Cardiopulmonary Resuscitation ; Survival
2.Post-resuscitation care of patients with return of spontaneous circulation after out-of-hospital cardiac arrest at the emergency department.
Jing Kai Jackie LAM ; Jen Heng PEK
Singapore medical journal 2025;66(2):66-72
INTRODUCTION:
Out-of-hospital-cardiac-arrest (OHCA) is a major public health challenge and post-return-of-spontaneous-circulation (ROSC) goals have shifted from just survival to survival with intact neurology. Although post-ROSC care is crucial for survival with intact neurology, there are insufficient well-established protocols for post-resuscitation care. We aimed to evaluate post-resuscitation care in the emergency department (ED) of adult (aged ≥16 years) OHCA patients with sustained ROSC and its associated neurologically intact survival.
METHODS:
A retrospective review of electronic medical records was conducted for OHCA patients with sustained ROSC at the ED. Data including demographics, pre-hospital resuscitation, ED resuscitation, post-resuscitation care and eventual outcomes were analysed.
RESULTS:
Among 921 OHCA patients, 85 (9.2%) had sustained ROSC at the ED. Nineteen patients (19/85, 22.4%) survived, with 13 (13/85, 15.3%) having intact neurology at discharge. Electrocardiogram and chest X-ray were performed in all OHCA patients, whereas computed tomography (CT) was performed inconsistently, with CT brain being most common (74/85, 87.1%), while CT pulmonary angiogram (6/85, 7.1%), abdomen and pelvis (4/85, 4.7%) and aortogram (2/85, 2.4%) were done infrequently. Only four patients (4.7%) had all five neuroprotective goals of normoxia, normocarbia, normotension, normothermia and normoglycaemia achieved in the ED. The proportion of all five neuroprotective goals being met was significantly higher ( P = 0.01) among those with neurologically intact survival (3/13, 23.1%) than those without (1/72, 1.4%).
CONCLUSION
Post-resuscitation care at the ED showed great variability, indicating gaps between recommended guidelines and clinical practice. Good quality post-resuscitation care, centred around neuroprotection goals, must be initiated promptly to achieve meaningful survival with intact neurology.
Humans
;
Out-of-Hospital Cardiac Arrest/mortality*
;
Retrospective Studies
;
Male
;
Female
;
Middle Aged
;
Emergency Service, Hospital
;
Cardiopulmonary Resuscitation/methods*
;
Return of Spontaneous Circulation
;
Aged
;
Adult
;
Treatment Outcome
;
Electrocardiography
;
Tomography, X-Ray Computed
;
Aged, 80 and over
3.Characteristics and outcomes of out-of-hospital cardiac arrest among students under school supervision in Japan: a descriptive epidemiological study (2008-2021).
Kosuke KIYOHARA ; Mamoru AYUSAWA ; Masahiko NITTA ; Takeichiro SUDO ; Taku IWAMI ; Ken NAKATA ; Yuri KITAMURA ; Tetsuhisa KITAMURA
Environmental Health and Preventive Medicine 2025;30():4-4
BACKGROUND:
A comprehensive understanding of the epidemiology of pediatric out-of-hospital cardiac arrest (OHCA) occurring under school supervision is lacking. We aimed to comprehensively describe the characteristics and outcomes of OHCA among students in elementary schools, junior high schools, high schools, and technical colleges in Japan.
METHODS:
OHCA data from 2008-2021 were obtained from the SPIRITS study, which provides a nationwide database of OHCAs occurring under school supervision across Japan. We included cases in which resuscitation was attempted by emergency medical service personnel or bystanders. The cases were classified into three groups based on their etiology: cardiac, non-cardiac, and traumatic origin. The primary outcome was one-month survival with favorable neurological outcomes, defined as a Glasgow-Pittsburgh cerebral performance category of 1 or 2. The demographic characteristics, event details, and outcomes were compared across the three groups by using χ2 tests for categorical variables and one-way analyses of variance for continuous variables.
RESULTS:
During the 14-year study period, 602 OHCA cases were confirmed, with 430 (71.4%) classified as cardiac, 91 (15.1%) as non-cardiac, and 81 (13.5%) as traumatic origin. Non-cardiac and traumatic cases were less likely to be witnessed at the time of arrest (46.2% and 42.0%, respectively) than cardiac cases (82.6%; p < 0.001). Initiation of cardiopulmonary resuscitation by bystanders was less common in non-cardiac and traumatic cases (62.6% and 42.0%, respectively) than that in cardiac cases (82.8%; p < 0.001). The delivery of defibrillation using public-access automated external defibrillators was also significantly less frequent in non-cardiac (3.3%) and traumatic cases (6.2%) than that in cardiac cases (59.8%; p < 0.001). Ventricular fibrillation (VF) as the first documented rhythm was observed in 77.9% of cardiac cases but was much less common in non-cardiac (5.5%) and traumatic cases (8.6%; p < 0.001). One-month survival with favorable neurological outcomes was significantly lower in non-cardiac (6.6%) and traumatic cases (0%) than that in cardiac cases (50.2%; p < 0.001).
CONCLUSIONS
OHCAs of cardiac origin were more frequently associated with VF and had relatively good prognoses. In contrast, OHCAs of non-cardiac and traumatic origins consistently resulted in poor outcomes, highlighting the critical importance of prevention strategies to reduce the occurrence of these incidents.
Out-of-Hospital Cardiac Arrest/etiology*
;
Humans
;
Japan/epidemiology*
;
Male
;
Female
;
Child
;
Students/statistics & numerical data*
;
Schools/statistics & numerical data*
;
Adolescent
;
Cardiopulmonary Resuscitation/statistics & numerical data*
;
Emergency Medical Services/statistics & numerical data*
;
Epidemiologic Studies
4.Summary and interpretation of the Improving outcomes after post-cardiac arrest brain injury: a scientific statement from the International Liaison Committee on Resuscitation.
Aolin XIA ; Tianfeng HUA ; Min YANG
Chinese Critical Care Medicine 2025;37(2):97-102
Post-cardiac arrest brain injury (PCABI) remains the main cause of death and poor prognosis in patients after resuscitation. In June 2024, the International Liaison Committee on Resuscitation (ILCOR) released a scientific statement on improving the prognosis of PCABI based on relevant research progress. The statement proposed the pathological mechanism of PCABI, explored the reasons why previous preclinical data could not be translated into clinical practice, and outlined possible future directions for advancement. This article interprets the key content of the 2024 ILCOR scientific statement on improving the prognosis of PCABI, hoping to provide reference and assistance for domestic medical staff to understand and apply this scientific statement.
Humans
;
Heart Arrest/therapy*
;
Brain Injuries/therapy*
;
Cardiopulmonary Resuscitation
;
Prognosis
;
Resuscitation
5.Current practice, prognostic risk factors and management strategies of pre-hospital extracorporeal cardiopulmonary resuscitation in China.
Liangliang ZHOU ; Jianjun CHEN ; Jing WU ; Yijun DENG ; Renyu DING
Chinese Critical Care Medicine 2025;37(2):103-110
With the gradual development and popularization of extracorporeal membrane oxygenation (ECMO) in China, some prefecture-level medical institutions in China have carried out and formed their own pre-hospital extracorporeal cardiopulmonary resuscitation (ECPR) model. Although the development levels of various prefecture-level cities are uneven and the start times vary, at present, the prefecture-level hospitals in China generally go through the development process of ECMO-in-hospital ECPR-pre-hospital ECPR-professional medical recovery center. Among them, in-hospital ECPR has the advantages of timely resuscitation, guaranteed quality of resuscitation, and fast activation speed of the ECPR team, and currently has a high success rate, with a low proportion of patients with neurological complications. However, pre-hospital ECPR is more challenging, requiring the coordination between pre-hospital and in-hospital emergency forces, multidisciplinary cooperation, and the quality of resuscitation before ECPR cannot be fully guaranteed, the long duration of patient's low perfusion, and other factors make the survival rate of patients without neurological damage obviously lower than that of in-hospital ECPR. China has a large population base, and comprehensive domestic and foreign data show that there should be no less than several million cases of out-of-hospital cardiac arrest under the age of 60 every year, so there is much to be done to improve the survival rate of pre-hospital ECPR. Pre-hospital ECPR is a project of concentrated resources and technology, which has high requirements for the multidisciplinary diagnosis and treatment capabilities of medical institutions. The optimization of the implementation process of in-hospital and pre-hospital ECPR teams, the advancement of the timing of ECPR intervention, the selection of patients, the support and construction of multidisciplinary diagnosis and treatment capabilities after ECPR, and the management of related complications and risk factors are closely related to the prognosis of ECPR patients. The recoverability of the brain and heart is currently the key factor restricting the further improvement of the survival rate of patients after ECPR. Considering that the recovery of neurological function mainly depends on the duration of the early low perfusion, the in-hospital treatment after the implementation of ECPR is mainly the low-temperature brain protection strategy, the effect of which is still controversial, so the recovery of cardiac function is the key that seriously restricts the survival of patients after ECPR in addition to neurological prognosis. The recoverability of the heart after ECPR can be implemented from multiple angles: the research on pathophysiological issues such as the matching of the heart itself after the implementation of ECPR, and the matching between the heart and ECMO, and the proposal of corresponding countermeasures will help to improve the survival rate of patients after ECPR. The large population and the potential salvageable population make the development of ECPR technology in China's tertiary hospitals urgent and necessary, with challenges and opportunities coexisting.
Humans
;
Cardiopulmonary Resuscitation/methods*
;
China
;
Extracorporeal Membrane Oxygenation/methods*
;
Emergency Medical Services
;
Risk Factors
;
Prognosis
6.Mechanism of human embryonic stem cell-derived mesenchymal stem cells on alleviating brain injury after cardiopulmonary resuscitation in swine with cardiac arrest.
Feng GE ; Jiefeng XU ; Jinjiang ZHU ; Guangli CAO ; Xuguang WANG ; Meiya ZHOU ; Tiejiang CHEN ; Mao ZHANG
Chinese Critical Care Medicine 2025;37(2):133-139
OBJECTIVE:
To investigate the mechanism of human embryonic stem cell-derived mesenchymal stem cells (hESC-MSC) in alleviating brain injury after resuscitation in swine with cardiac arrest (CA).
METHODS:
Twenty-nine healthy male large white swine were randomly divided into Sham group (n = 9), cardiopulmonary resuscitation (CPR) group (n = 10) and hESC-MSC group (n = 10). The Sham group only completed animal preparation. In CPR group and hESC-MSC group, the swine model of CA-CPR was established by inducing ventricular fibrillation for 10 minutes with electrical stimulation and CPR for 6 minutes. At 5 minutes after successful resuscitation, hESC-MSC 2.5×106/kg was injected via intravenous micropump within 1 hour in hESC-MSC group. Venous blood samples were collected before resuscitation and at 4, 8, 24, 48 and 72 hours of resuscitation. The levels of neuron specific enolase (NSE) and S100B protein (S100B) were detected by enzyme linked immunosorbent assay (ELISA). At 24, 48 and 72 hours of resuscitation, neurological deficit score (NDS) and cerebral performance category (CPC) were used to evaluate the neurological function of the animals. Three animals from each group were randomly selected and euthanized at 24, 48, and 72 hours of resuscitation, and the hippocampus tissues were quickly obtained. Immunofluorescence staining was used to detect the distribution of hESC-MSC in hippocampus. Immunohistochemical staining was used to detect the activation of astrocytes and microglia and the survival of neurons in the hippocampus. The degree of apoptosis was detected by TdT-mediated dUTP nick end labeling (TUNEL).
RESULTS:
The serum NSE and S100B levels of brain injury markers in CPR group and hESC-MSC group were significantly higher than those in Sham group at 24 hours of resuscitation, and then gradually increased. The levels of NSE and S100B in serum at each time of resuscitation in hESC-MSC group were significantly lower than those in CPR group [NSE (μg/L): 20.69±3.62 vs. 28.95±3.48 at 4 hours, 27.04±5.56 vs. 48.59±9.22 at 72 hours; S100B (μg/L): 2.29±0.39 vs. 3.60±0.73 at 4 hours, 2.38±0.15 vs. 3.92±0.50 at 72 hours, all P < 0.05]. In terms of neurological function, compared with the Sham group, the NDS score and CPC score in the CPR group and hESC-MSC group increased significantly at 24 hours of resuscitation, and then gradually decreased. The NDS and CPC scores of hESC-MSC group were significantly lower than those of CPR group at 24 hours of resuscitation (NDS: 111.67±20.21 vs. 170.00±21.79, CPC: 2.33±0.29 vs. 3.00±0.00, both P < 0.05). The expression of hESC-MSC positive markers CD73, CD90 and CD105 in the hippocampus of hESC-MSC group at 24, 48 and 72 hours of resuscitation was observed under fluorescence microscope, indicating that hESC-MSC could homing to the damaged hippocampus. In addition, compared with Sham group, the proportion of astrocytes, microglia and apoptotic index in hippocampus of CPR group were significantly increased, and the proportion of neurons was significantly decreased at 24, 48 and 72 hours of resuscitation. Compared with CPR group, the proportion of astrocytes, microglia and apoptotic index in hippocampus of hESC-MSC group decreased and the proportion of neurons increased significantly at 24 hours of resuscitation [proportion of astrocytes: (14.33±1.00)% vs. (30.78±2.69)%, proportion of microglia: (12.00±0.88)% vs. (27.89±5.68)%, apoptotic index: (12.89±3.86)% vs. (52.33±7.77)%, proportion of neurons: (39.44±3.72)% vs. (28.33±1.53)%, all P < 0.05].
CONCLUSIONS
Application of hESC-MSC at the early stage of resuscitation can reduce the brain injury and neurological dysfunction after resuscitation in swine with CA. The mechanism may be related to the inhibition of immune cell activation, reduction of cell apoptosis and promotion of neuronal survival.
Animals
;
Heart Arrest/therapy*
;
Cardiopulmonary Resuscitation
;
Swine
;
Humans
;
Male
;
Human Embryonic Stem Cells/cytology*
;
Mesenchymal Stem Cell Transplantation
;
Mesenchymal Stem Cells/cytology*
;
Phosphopyruvate Hydratase/blood*
;
Brain Injuries/therapy*
;
S100 Calcium Binding Protein beta Subunit
;
Apoptosis
;
Disease Models, Animal
7.Design and application of a cardiopulmonary resuscitation compression depth limiting device.
Zhifang XUE ; Shuao ZHAO ; Hao LI ; Rongzhao GU ; Rong HUA ; Xianliang YAN
Chinese Critical Care Medicine 2025;37(2):180-182
During cardiopulmonary resuscitation (CPR), the depth of compression is a critical factor affecting the effectiveness of the rescue and the patient's prognosis. However, it is difficult to master the correct compression depth in manual CPR. If the compression depth is too deep, it may cause rib fractures, while insufficient compression depth may fail to establish effective circulation. Although most existing manual CPR compression depth control devices can indicate the depth but lack direct limiting functions. Against this background, led by a team of faculty and students from the Department of Emergency and Rescue Medicine at Xuzhou Medical University, on the basis of the development of a portable CPR protection device (National Invention Patent of China, patent number: ZL 2021 1 0309001.4), the device's compression depth limiting performance was further expanded, and then a new type of CPR compression depth limiting device suitable for different body types was developed. This device has applied for a National Invention Patent of China (patent application number: ZL 2023 1 0644910.2) and has been granted a National Utility Model Patent of China (patent number: ZL 2023 2 1384853.0). The device consists of a horizontal support beam, a vertical sliding beam, a guide block, a rotating shaft, a rotating arm, a limit slider and a limit pin. The horizontal support beams of the two limit devices are fixed horizontally to the horizontal side beams of the portable CPR protection device by bolts, and the connecting arms at the bottom of the vertical sliding beams are fixedly connected with the pressing mechanism, so that precise control of the pressing depth in CPR operation can be realized according to the patient's body size by the mechanical linkage of the vertical sliding beams and the rotating arms, as well as by the blocking and limiting effect of the rotating arms and the guiding blocks on the limiting sliders. It can prevent the occurrence of complications such as chest wall fractures, and thereby increase the success rate of manual CPR, and its structure is simple, low-cost, and suitable for social popularization.
Cardiopulmonary Resuscitation/instrumentation*
;
Humans
;
Equipment Design
;
Pressure
8.Annual review of clinical research on extracorporeal life support in 2024.
Hongling ZHANG ; Yuan YU ; Zhongtao DU ; Xiaojing ZOU ; Xiaotong HOU ; You SHANG
Chinese Critical Care Medicine 2025;37(4):317-323
The important studies in the field of extracorporeal life support (ECLS) in 2024 focused on the application of cardiac support technologies in acute myocardial infarction (AMI) with cardiogenic shock (CS): veno-arterial extracorporeal membrane oxygenation (V-A ECMO) has not shown advantages in either short- or long-term outcomes and may increase the risk of bleeding and vascular complications; in contrast, micro-axial flow pumps demonstrate potential in improving mortality. The effects of veno-venous extracorporeal membrane oxygenation (V-V ECMO) combined with prone positioning on severe acute respiratory distress syndrome (ARDS) remain uncertain. The survival benefit of extracorporeal cardiopulmonary resuscitation (ECPR) in out-of-hospital cardiac arrest (OHCA) patients has been further validated. The potential benefits of extracorporeal carbon dioxide removal (ECCO2R) require further investigation. Additionally, new guidelines released in 2024 focus on Neurological monitoring and management during ECMO, as well as the Definition and management of right ventricular injury during veno-venous ECMO. ECMO management requires more refined strategies, including optimized oxygenation targets, anticoagulation, blood transfusion, and weaning strategies to improve patient outcomes.
Humans
;
Extracorporeal Membrane Oxygenation/methods*
;
Shock, Cardiogenic/therapy*
;
Cardiopulmonary Resuscitation
;
Myocardial Infarction/therapy*
9.The impact of different chest compression frequencies on cardiopulmonary resuscitation outcomes in domestic pigs.
Nana XU ; Jiabi ZHANG ; Jialin LUO ; Li WANG ; Yong CHEN ; Lijun ZHOU ; Bihua CHEN ; Lan LUO ; Xiaolu LIU ; Shuju LUO ; Yong WANG ; Zunwei LUO ; Li DING ; Mei LI ; Manhong ZHOU
Chinese Critical Care Medicine 2025;37(5):472-476
OBJECTIVE:
To compare the effects of different chest compression rates (60-140 times/min) on hemodynamic parameters, return of spontaneous circulation (ROSC), resuscitation success, and survival in a porcine model of cardiac arrest (CA) followed by cardiopulmonary resuscitation (CPR).
METHODS:
Forty healthy male domestic pigs were randomly divided into five groups based on chest compression rate: 60, 80, 100, 120, and 140 times/min (n = 8). All animals underwent standard anesthesia and tracheal intubation. A catheter was inserted via the left femoral artery into the thoracic aorta to monitor aortic pressure (AOP), and another via the right external jugular vein into the right atrium to monitor right atrial pressure (RAP). In each group, animals were implanted with a stimulating electrode via the right external jugular vein to the endocardium, and ventricular fibrillation (VF) was induced by delivering alternating current stimulation, resulting in CA. After a 1-minute, manual chest compressions were performed at the assigned rate with a compression depth of 5 cm. The first defibrillation was delivered after 2 minutes of CPR. No epinephrine or other pharmacologic agents were administered during the entire resuscitation process. From 1 minute before VF induction to 10 minutes after ROSC, dynamic monitoring of AOP, coronary perfusion pressure (CPP), and partial pressure of end-tidal carbon dioxide (PETCO2). Cortical ultrastructure was examined 24 hours post-ROSC using transmission electron microscopy.
RESULTS:
With increasing compression rates, both the total number of defibrillations and cumulative defibrillation energy significantly decreased, reaching their lowest levels in the 120 times/min group. The number of defibrillations decreased from (4.88±0.83) times in the 60 times/min group to (2.25±0.71) times in the 120 compressions/min group, and energy from (975.00±166.90)J to (450.00±141.42)J. However, both parameters increased again in the 140 times/min group [(4.75±1.04)times, (950.00±207.02)J], the differences among the groups were statistically significant (both P < 0.01). As compression frequency increased, PETCO2, pre-defibrillation AOP and CPP significantly improved, peaking in the 120 times/min group [compared with the 60 times/min group, PETCO2 (mmHg, 1 mmHg≈0.133 kPa): 18.69±1.98 vs. 8.67±1.30, AOP (mmHg): 95.13±7.06 vs. 71.00±6.41, CPP (mmHg): 14.88±6.92 vs. 8.57±3.42]. However, in the 140 times/min group, these values declined significantly again [PETCO2, AOP, and CPP were (10.59±1.40), (72.38±11.49), and (10.36±4.57) mmHg, respectively], the differences among the groups were statistically significant (all P < 0.01). The number of animals achieving ROSC, successful resuscitation, and 24-hour survival increased with higher compression rates, reaching a peak in the 120 times/min group (compared with the 60 times/min group, ROSC: 7 vs. 2, successful resuscitation: 7 vs. 2, 24-hour survival: 7 vs.1), then decreased again in the 140 times/min group (the animals that ROSC, successfully recovered and survived for 24 hours were 3, 3, and 2, respectively). Transmission electron microscopy revealed that in the 60, 80, and 140 times/min groups, nuclear membranes in cerebral tissue were irregular and incomplete, nucleoli were indistinct, and mitochondria were swollen with reduced cristae and abnormal morphology. In contrast, the 100 times/min and 120 times/min groups exhibited significantly attenuated ultrastructural damage.
CONCLUSIONS
Among the tested chest compression rates of 60-140 times/min, a chest compressions frequency of 120 times/min is the most favorable hemodynamic profile and outcomes during CPR in a porcine CA model. However, due to the wide spacing between groups, further investigation is needed to determine the optimal compression rate range more precisely.
Animals
;
Cardiopulmonary Resuscitation/methods*
;
Swine
;
Male
;
Heart Arrest/therapy*
;
Heart Massage/methods*
;
Hemodynamics
10.6-Shogaol alleviates cerebral injury after cardiac arrest-cardiopulmonary resuscitation in rats by inhibiting death-associated protein kinase 1-mediated autophagy.
Ouyang RAO ; Shixin LI ; Ning ZHU ; Hangxiang ZHOU ; Jie HU ; Yun LI ; Junling TAO ; Yehong LI ; Ying LIU
Chinese Critical Care Medicine 2025;37(6):568-575
OBJECTIVE:
To observe the neuroprotective effect of 6-shogaol (6-SH) in global cerebral ischemia/reperfusion injury (CIRI) following cardiac arrest (CA) and cardiopulmonary resuscitation (CPR) in rats.
METHODS:
Computer-aided molecular docking was used to determine whether 6-SH could spontaneously bind to death-associated protein kinase 1 (DAPK1). SPF-grade male SD rats were randomly divided into a sham group (n = 5), a CPR group (n = 7), and a CPR+6-SH group (n = 7). The CPR group and CPR+6-SH group were further divided into 12-, 24-, and 48-hour subgroups based on observation time points. A rat model of global CIRI after CA-CPR was established by asphyxiation. In the sham group, only tracheal and vascular intubation was performed without asphyxia and CPR induction. The CPR group was intraperitoneally injected with 1 mL of normal saline immediately after successful modeling. The CPR+6-SH group received an intraperitoneal injection of 20 mg/kg 6-SH (1 mL) immediately after successful modeling, followed by administration every 12 hours until the endpoint. Neurological Deficit Score (NDS) was recorded at each time point after modeling. After completion of observation at each time point, rats were anesthetized and sacrificed, and brain tissue specimens were collected. Histopathological changes of neurons were observed under light microscopy after hematoxylin-eosin (HE) staining. Ultrastructural changes of hippocampal neurons and autophagy were observed by transmission electron microscopy (TEM). Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect mRNA expression levels of DAPK1, vacuolar protein sorting 34 (VPS34), Beclin1, and microtubule-associated protein 1 light chain 3 (LC3) in brain tissues. Western blotting was used to detect protein expression levels of DAPK1, phosphorylated DAPK1 at serine 308 (p-DAPK1 ser308), VPS34, Beclin1, and LC3. Immunofluorescence was used to observe Beclin1 and LC3 expression in brain tissues under a fluorescence microscope.
RESULTS:
Molecular docking results indicated that 6-SH could spontaneously bind to DAPK1. Compared with the sham group, the NDS scores of the CPR group rats were significantly increased at all modeling time points; under light microscopy, disordered cell arrangement, widened intercellular spaces, and edema were observed in brain tissues, with pyknotic and necrotic nuclei in some areas; under TEM, mitochondria were markedly swollen with intact membranes, dissolved matrix, reduced or disappeared cristae, vacuolization, and increased autophagosomes. Compared with the CPR group, the NDS scores of the CPR+6-SH group rats were significantly decreased at all modeling time points; under light microscopy, local neuronal edema and widened perinuclear space were observed; under TEM, mitochondria were mostly mildly swollen with intact membranes, fewer autophagosomes, and alleviated injury. RT-qPCR results showed that compared with the sham group, mRNA expression levels of DAPK1, VPS34, Beclin1, and LC3 in brain tissues were significantly upregulated in all CPR subgroups, with the most pronounced changes at 24 hours. Compared with the CPR group, the CPR+6-SH group showed significantly lower mRNA expression of the above indicators at each time point [24 hours post-modeling (relative expression): DAPK1 mRNA: 3.41±0.68 vs. 4.48±0.62; VPS34 mRNA: 3.63±0.49 vs. 4.66±1.18; Beclin1 mRNA: 3.08±0.49 vs. 4.04±0.22; LC3 mRNA: 2.60±0.36 vs. 3.67±0.62; all P < 0.05]. Western blotting results showed that compared with the sham group, the protein expression levels of DAPK1, VPS34, Beclin1, and LC3 in all CPR subgroups were significantly increased, while the expression of p-DAPK1 ser308 was significantly decreased, with the most pronounced changes observed in the CPR 24-hour subgroup. Compared with the CPR group, the CPR+6-SH subgroups exhibited significantly reduced protein expression of DAPK1, VPS34, Beclin1, and LC3 [24-hour post-modeling: DAPK1/β-actin: 1.88±0.22 vs. 2.47±0.22; VPS34/β-actin: 2.55±0.06 vs. 3.46±0.05; Beclin1/β-actin: 2.12±0.03 vs. 2.87±0.03; LC3/β-actin: 2.03±0.24 vs. 3.17±0.23; all P < 0.05]. Conversely, the expression of p-DAPK1 ser308 was significantly upregulated in the CPR+6-SH group compared to the CPR group [24-hour post-modeling: p-DAPK1 ser308/β-actin: 0.40±0.02 vs. 0.20±0.07, P < 0.05]. Under the fluorescence microscope, fluorescence intensities of Beclin1 and LC3 in the CPR 24-hour group were significantly higher than those in the sham 24-hour group; compared with the CPR 24-hour group, the CPR+6-SH 24-hour group showed significantly reduced fluorescence intensities of Beclin1 and LC3.
CONCLUSION
6-SH inhibited the expression of DAPK1, alleviated excessive autophagy after global CIRI following CA-CPR in rats, and exerted neuroprotective effects. The mechanism may be related to phosphorylation at the DAPK1 ser308 site.
Animals
;
Rats, Sprague-Dawley
;
Male
;
Rats
;
Cardiopulmonary Resuscitation
;
Autophagy/drug effects*
;
Heart Arrest/therapy*
;
Death-Associated Protein Kinases/metabolism*
;
Reperfusion Injury/metabolism*
;
Disease Models, Animal
;
Neuroprotective Agents/pharmacology*
;
Brain Ischemia/metabolism*


Result Analysis
Print
Save
E-mail