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As with their human counterparts, police K-9s face dangers, including death, while in service. However, police K-9 research is significantly lacking, limiting possible preventive interventions. As such, we use data collected by the Officer Down Memorial Page from 2000–2023 on K-9 deaths (N = 407) to understand trends and correlates of these line-of-duty deaths, with an emphasis on heatstroke. Following gunfire, heatstroke is the second-leading cause of line-of-duty deaths for K-9s, with more than one in five deaths attributed to heatstroke. Being left unattended and mechanical failures overwhelmingly (70.6%) characterized these heatstroke deaths. Summer months were also significantly implicated in increasing the odds of line-of-duty heatstroke deaths. However, age, gender, breed, and climate region were not associated. [ABSTRACT FROM AUTHOR]

This retrospective multicenter study was conducted across 83 intensive care units (ICUs) in 16 cities in Sichuan, China. Critically ill patients diagnosed with heatstroke and lung infections were included in the study. Specimens from the lower respiratory tract were collected for microbiological testing, and the characteristics of the pathogens were described. A total of 462 patients diagnosed with heatstroke-related pulmonary infections were included, 134 patients (29.0%) tested positive for respiratory pathogens. The most frequently isolated strain was Klebsiella pneumoniae (34.3%), followed by Escherichia coli (28.4%), Staphylococcus aureus (20.9%). The results revealed that in the hyperthermic resistance group, there was a higher proportion of Pseudomonas aeruginosa [14(34.1%) vs 11(11.8%), p =0.002] and Stenotrophomonas maltophilia [4(9.8%) vs 1(1.1%), p =0.030] compared to the hyperthermic control group. And a higher proportion of Staphylococcus aureus [27(29.7%) vs 1(2.3%), p <0.001], were obtained during the earlier stages with elevated temperatures. Patients with Klebsiella pneumoniae (38.3 ± 1.9°C), Staphylococcus aureus (38.5 ± 2.2°C), and Pseudomonas aeruginosa (38.7 ± 1.9°C) exhibited a higher temperature environment. Our study provides crucial insights into the lower respiratory tract pathogenesis of heatstroke patients, identifying key pathogens and their temperature-dependent characteristics, thus providing a foundation for future empirical treatment strategies in heatstroke. [ABSTRACT FROM AUTHOR]

In May and June 2024, a die‐off of Mexican mantled howler monkeys (Alouatta palliata mexicana) occurred in southern Mexico. This commentary documents the event, attributing it to extreme heatwaves, drought, wildfires, and habitat impoverishment. Despite their reported resilience to habitat disturbances, mantled howler monkey mortality rate in some areas reached 31%. Key evidence points to heatstroke as the primary cause of death, exacerbated by limited hydration and reduced dietary diversity in disturbed habitats. Immediate responses included community‐led rescues (e.g., hydrating the monkeys), coordination of rescue activities by nongovernmental organizations (NGOs) (e.g., managing donations), involvement of scientists (e.g., monitoring of primate populations), and assistance from government officials (e.g., providing legal support for animal management). This event underscores the urgency of developing action plans to prevent and attend future crises. Among other actions, we highlight (i) establishing primate care infrastructure with medical and rehabilitation centers; (ii) developing protocols and training programs to ensure rapid crisis response; (iii) fostering collaboration among government, NGOs, and academic institutions for effective crisis management; and (iv) developing targeted research on climate change impacts, predictive models, and long‐term health monitoring. We emphasize the critical need for coordinated conservation efforts to protect wild primates and maintain natural ecosystem resilience in the face of escalating climate challenges. Summary: In May and June 2024, over 300 howler monkeys died in southern Mexico.Key evidence points to heatstroke as the primary cause of death, exacerbated by limited hydration and reduced dietary diversity in disturbed habitats.This event highlights the critical need for coordinated conservation efforts to protect wild primates in the face of escalating climate challenges. [ABSTRACT FROM AUTHOR]

Heatstroke (HS) is a severe systemic condition that significantly impacts organ function, with the liver being particularly vulnerable. Sirtuin 1 (SIRT1), a crucial deacetylase, is implicated in various diseases' pathophysiology. Curcumin, a natural polyphenol, has been shown to modulate SIRT1 activity, offering therapeutic benefits. This study explores the impact of HS on hepatic SIRT1 expression and the protective mechanisms of curcumin against HS‐induced hepatic injury. Male C57BL/6 mice are divided into control and curcumin pretreatment groups, subjected to HS induction, and assessed for liver injury biomarkers, oxidative stress, and inflammatory cytokines. Results indicate that HS downregulates SIRT1, leading to liver damage and systemic inflammation. Curcumin pretreatment dose‐responsively attenuates these effects, with the highest dose providing optimal protection, potentially through SIRT1 restoration. The findings suggest that curcumin's hepatoprotective role in HS may be mediated by upregulating SIRT1, highlighting its therapeutic potential in heatstroke‐related liver damage. [ABSTRACT FROM AUTHOR]

Heat exhaustion (HE) is a common, yet obscure, heat-related illness that affects millions of people yearly and its burden is projected to rise due to climate change. A comprehensive literature synthesis is lacking despite previous studies on various HE aspects. This systematic review aims to fill this gap by identifying and synthesizing available evidence on the risk factors, symptoms, biomarkers, treatment options, and outcomes for HE. The review focused on HE during the Muslim (Hajj) pilgrimage where the condition is endemic. We conducted a structured search of MEDLINE/PubMed, Embase, Web of Science Core Collection, SCOPUS, and CINAHL databases. We summarized the data from eligible studies and synthesized them in narrative form using pooled descriptive statistics. Ten studies were included between 1980 and 2019, reporting over 1,194 HE cases. HE cases presented with elevated core temperature (up to 40°C) and mainly affected older males from the Middle East and North Africa region, with overweight individuals at a higher risk. Clinical symptoms included hyperventilation, fatigue, dizziness, headaches, nausea, and vomiting, but not central nervous system disturbances. HE was associated with cardiac stress, and with water, electrolyte, and acid-base alterations. Cooling and hydration therapy were the primary management strategies, leading to a low mortality rate (pooled case fatality rate=0.11 % [95 % CI: 0.01, 0.3]). Most cases recovered within a few hours without complications. HE is associated with cardiac stress and changes in homeostasis, leading to distinct clinical symptoms. Early diagnosis and treatment of HE are crucial in reducing the risk of complications and mortality. The review provides insights into the pathophysiology and outcomes of HE, adding to the scarce literature on the subject. Prospero registration number: CRD42022325759. [ABSTRACT FROM AUTHOR]

The occurrence of sequelae is common after heatstroke. There is a lack of risk prediction data regarding the prevalence of sequelae. This study aims to develop a predictive model for the sequelae after heatstroke, including cerebellar dysfunction. Heatstroke patients admitted to our hospital in the past 8 years were retrospectively enrolled. Regression analyses were conducted to identify risk factors associated with sequelae and cerebellar dysfunction. A prediction model for post-heatstroke sequelae was developed and internally and externally validated. Twenty-three percent of the patients experienced sequelae, with cerebellar dysfunction accounting for 51.7%. Patients with sequelae had longer duration of hyperthermia and coma, lower Glasgow Coma Scales scores, elevated core temperature, increased incidence of multiple organ dysfunction upon admission, and a worse prognosis compared to non-sequelae patients. Patients with cerebellar injury exhibited impaired balance, and a Sepsis-related Organ Failure Assessment (SOFA) score > 5 is an independent risk factor. The prediction system included advanced age, coma, and an APACHE-II score > 10 upon admission, predicting sensitivity = 0.8966, specificity = 0.8925, and AUC of ROC curve = 0.941 (95% CI: 0.884 ~ 0.976). The C-index in the internal verification was 0.942 (95% CI: 0.847 ~ 0.981) and the AUC in the external verification was 0.816 (95% CI: 0.699 ~ 0.902). The prediction system included advanced age, coma, and higher APACHE-II scores as variables, indicating a significant prevalence of sequelae. Higher SOFA scores were associated with the increased occurrence of cerebellar dysfunction and balance impairment. The prediction system could better predict sequelae after heatstroke.

Record-breaking heat waves over the past 20 years have led to a global increase in heat-related deaths, including heatstroke. Heat-related illnesses occur when the body cannot adapt to the elevated temperatures in the environment, leading to various symptoms. In severe situations, such as heatstroke, the body temperature can rise above 40°C, leading to significant injury to body systems, with particular susceptibility of the central nervous system (CNS). Neuroimaging studies conducted months or years after a heatstroke have revealed cellular damage in the cerebellum and other brain regions, including the hippocampus, midbrain, and thalamus, with the potential for long-term neurological complications in survivors of a heatstroke. This mini review aimed to describe the mechanisms and pathways underlying the development of brain injury induced by heatstroke and identify diagnostic imaging tools and biomarkers for injury to the CNS due to a heatstroke. [ABSTRACT FROM AUTHOR]

Background & Objectives: The present study investigates the therapeutic potential of betaine-conjugated gold nanoparticles (AuNPs) in treating inflammation induced by heatstroke. While heatstroke is characterized by elevated body temperature and severe inflammation, which can lead to organ dysfunction, conventional treatments, such as cooling and supportive care have not been successful in preventing long-term damage. AuNPs function as targeted carriers for the delivery of bioactive agents, such as betaine, to inflamed tissues. Using a murine model of heatstroke, we assessed the effects of AuNPs, betaine, and their combination on inflammation markers and cellular stress. Materials & Methods: The experimental animals were divided into groups receiving different treatments, and various outcomes, including cytokine levels (TNF-α, IL-6, IL- 10), heat shock protein (HSP70) expression, and splenocyte proliferation, were measured. Results: The findings revealed that the combination of AuNPs and betaine significantly decreased the levels of pro-inflammatory cytokines (TNF-α and IL-6) while increasing those of the anti-inflammatory cytokine IL-10. Furthermore, the therapy reduced HSP70 expression, indicating lowered cellular stress in the AuNP-betaine group. Moreover, treatment with AuNP-betaine significantly enhanced lymphocyte proliferation, suggesting improved immune function under heatstroke conditions. Conclusion: Our findings highlight the promise of betaine-conjugated AuNPs as an innovative therapeutic approach in reducing inflammation and oxidative stress associated with heatstroke. The synergistic effects of nanotechnology and bioactive substances in modulating inflammatory pathways can be a promising strategy for managing heat-related inflammatory conditions. [ABSTRACT FROM AUTHOR]

Background: Heat-related illnesses (HRIs) have a wide spectrum from relatively mild heat cramps to heatstroke in its severest form. The 2024 heat wave in Delhi, with temperatures consistently above 40°C, resulted in over 270 deaths due to heatstroke. This study examines nine cases of classical heatstroke admitted over a 24-h period to a tertiary care hospital in Delhi. Materials and Methods: This is a cross-sectional study of patients presenting to emergency with altered consciousness during the 24-h period just before the culmination of the 40-day long heat wave period. In the absence of alternative etiologies on the investigation, a diagnosis of classical heatstroke was entertained. The sociodemographic details, clinical features, investigations, treatment, and outcomes of nine such patients are being reported. Results: Common symptoms observed in the patients were hyperthermia (100%), dehydration (100%), altered sensorium (100%), vomiting (33%), and seizures (33%). Laboratory findings showed respiratory alkalosis (100%), hypokalemia (88.8%), thrombocytopenia (88.8%), and transaminitis (77.7%). Eight heatstroke patients required mechanical ventilation. Despite intensive treatment, three patients died, whereas six were discharged in stable condition. Conclusion: The 2024 heat wave in Delhi highlighted the severe impact of extreme heat on health. The spectrum of clinical features in classical heatstroke has been outlined. The impact of heat wave was such that even normal individuals accustomed to high-heat environments developed HRI. Early recognition and rapid cooling are crucial in managing heatstroke. Improved public awareness, healthcare infrastructure, and management protocols are essential to mitigate the effects of future heat waves. [ABSTRACT FROM AUTHOR]

Part one of this series on heat-related illness described how the disease has been known and written about for thousands of years. Since then, there have been some improvements in our understanding of its risks, mechanisms and treatments. However, heat-related illness remains a significant problem, and can be fatal or cause ongoing disability even after the acute episode has passed. This narrative review, the second article in a two-part series describes current understanding of heat-related illness and offers an insight into what we may learn in the future about its cause and potential new treatments and strategies. [ABSTRACT FROM AUTHOR]

Heatstroke induces fluid loss and electrolyte abnormalities owing to high ambient temperature (AT) and relative humidity (RH). Aquaporin 1 (AQP1) is a key protein for water homeostasis; however, its role in heatstroke remains unclear. This study examines endothelial AQP1 in Tie2-Cre/LNL-AQP1 double transgenic (dTG) mice with upregulated Aqp1 in endothelial cells. For experimental heatstroke, mice were exposed to 41 °C AT and >99% RH. Blood, brain, kidney, and liver samples were collected 24 h later. Blood was analyzed for electrolytes and tissue damage markers, and organs were examined using morphological and immunohistological staining for 3-nitrotyrosine (3-NT), AQP1, and Iba-1. No difference in Aqp1 expression was observed in the whole brain; however, it was detected in dTG mice after capillary deprivation. AQP1 immunostaining revealed immunoreaction in blood vessels. After heat exposure, wild-type and dTG mice showed electrolyte abnormalities compared with non-heatstroke wild-type mice. Hepatic damage markers were significantly higher in dTG mice than in wild-type mice. Hematoxylin–eosin staining and 3-NT immunoreactivity in the liver indicated hepatic damage. The number of Iba-1-positive cells adherent to hepatic vasculature was significantly higher in dTG mice than in wild-type mice. This study is the first to suggest that endothelial AQP1 contributes to hepatic damage after heatstroke. [ABSTRACT FROM AUTHOR]

Abstract Heatstroke (HS) is a severe systemic condition that significantly impacts organ function, with the liver being particularly vulnerable. Sirtuin 1 (SIRT1), a crucial deacetylase, is implicated in various diseases' pathophysiology. Curcumin, a natural polyphenol, has been shown to modulate SIRT1 activity, offering therapeutic benefits. This study explores the impact of HS on hepatic SIRT1 expression and the protective mechanisms of curcumin against HS‐induced hepatic injury. Male C57BL/6 mice are divided into control and curcumin pretreatment groups, subjected to HS induction, and assessed for liver injury biomarkers, oxidative stress, and inflammatory cytokines. Results indicate that HS downregulates SIRT1, leading to liver damage and systemic inflammation. Curcumin pretreatment dose‐responsively attenuates these effects, with the highest dose providing optimal protection, potentially through SIRT1 restoration. The findings suggest that curcumin's hepatoprotective role in HS may be mediated by upregulating SIRT1, highlighting its therapeutic potential in heatstroke‐related liver damage.

Background: Central nervous system (CNS) injury is the most prominent feature of heatstroke and the hippocampus is prone to damage. However, the mechanisms underlying the heatstroke-induced hippocampal injury remain unclear. Hyperbaric oxygen (HBO) therapy prevents CNS injury in heatstroke mice. However, the underlying mechanisms of HBO in heatstroke-induced hippocampal injury remain unclear. This study aimed to elucidate the protective effects of HBO against hippocampal injury and its potential role in microglial pyroptosis in heatstroke rats.Methods: A rat heatstroke model and a heat stress model with a mouse microglial cell line (BV2) were, respectively, used to illustrate the effect of HBO on heat-induced microglial pyroptosis in vivo and in vitro. We used a combination of molecular and histological methods to assess microglial pyroptosis and neuroinflammation both in vivo and in vitro.Results: The results revealed that HBO improved heatstroke-induced survival outcomes, hippocampal injury, and neurological dysfunction in rats. In addition, HBO mitigates microglial pyroptosis and reduces the expression of pro-inflammatory cytokines in the hippocampus of heatstroke rats. In vitro experiments showed that HBO attenuated BV2 cell injury under heat stress. Furthermore, HBO prevented heat-induced pyroptosis of BV2 cells, and the expression of pro-inflammatory cytokines IL-18 and IL-1β was reduced. Mechanistically, HBO alleviates heatstroke-induced neuroinflammation and hippocampal injury by preventing microglial pyroptosis. Conclusions: In conclusion, HBO attenuates heatstroke-induced neuroinflammation and hippocampal injury by inhibiting microglial pyroptosis.

The editorial titled "Body temperature homeostasis: the biological thermostat" explores how the human body regulates temperature around 37°C through the nervous system acting as a biological thermostat. It discusses the importance of the preoptic area in maintaining body temperature homeostasis and inducing fever during infections. The text also delves into the effects of traumatic brain injury on thermoregulation, epidural-related maternal fever, therapeutic hypothermia, heatstroke, and the role of the Raphe Pallidus in regulating thermogenesis and cardiovascular function. The research aims to uncover new neuroregulatory mechanisms related to thermoregulation and develop treatments for febrile diseases. [Extracted from the article]

This study provides a comprehensive collection of open-access daily time-series datasets designed to quantify the association between short-term exposure to maximum temperature and heatstroke-related ambulance dispatches (HSAD) utilizing a two-stage time-stratified case-crossover design. The datasets include daily records of HSAD, maximum temperature (°C), and relative humidity (%) for the summer months (i.e., June to September) from 2015 to 2019, spanning all 47 Japanese prefectures and covering the entire country. These datasets are well-suited for time-series regression analyses to estimate location-specific maximum temperature-HSAD associations in Japan. The availability of data from multiple locations also facilitates the of regional differences by aggregating location-specific associations within broader geographical areas. This resource is intended to support researchers, educators, and students in leveraging time-series analysis for research and educational purposes.

Objective To analyze the occurrence of heatstroke cases in Baoshan District, Shanghai, in recent years and explore its association with meteorological conditions. Methods Daily heatstroke case information and corresponding meteorological data from June 15 to September 30 during 2013-2022 were collected. An ordinal logistic regression model was used to estimate the strength of the association between heatstroke occurrence and meteorological conditions and to calculate temperature reference values for heatstroke warnings. Results From 2013 to 2022, a total of 173 heatstroke cases were recorded in Baoshan District, with a male-to-female ratio of 6.2 : 1. The average age of heatstroke cases was (45.08 ± 17.85) years old, with 114 cases (65.9%) occurring in July. Ordinal logistic regression analysis showed that for each 1% increase in relative humidity, the risk of heatstroke was reduced to 0.901 times the original risk. Compared to non-rainfall days, the risk of heatstroke during rainfall days was reduced to 0.340 times the original risk. For each 1 °C increase in daily average temperature, daily maximum temperature, or daily minimum temperature, the risk of heatstroke increased to 2.005, 1.736, and 1.906 times the original risk, respectively. The risk of heatstroke during heatwave and high-temperature days increased to 11.896 and 15.819 times, respectively, compared to non-heatwave and non-high-temperature days. For the 3-day moving average temperature (i.e., the average temperature of the current day and the previous two days), each 1 °C increase in daily average temperature, daily maximum temperature, and daily minimum temperature increased the risk of heatstroke to 1.926, 1.699, and 1.957 times, respectively. All these differences were statistically significant (all P < 0.05). The daily average temperature, daily maximum temperature, and daily minimum temperature for the extreme heatstroke risk warning values are 35.55° C, 40.58° C, and 31.07° C, respectively. The three temperature meteorological conditions for the high heatstroke risk warning values are 28.87°C, 33.31°C, and 25.21°C, respectively. Conclusions July was the peak period for heatstroke in Baoshan District. Increases in daily average temperature, daily maximum temperature, and daily minimum temperature all increased the likelihood of heatstroke, with sustained relatively high daily minimum temperatures over 3 days being more likely to result in heatstroke. [ABSTRACT FROM AUTHOR]

Background: Heat-related illness is commonly seen in individuals undergoing physical exercise or exertion (exertional heat illness) and those exposed to high ambient temperatures, for example in heatwaves (classic heat illness). While severe heat-related illness, including heatstroke, requires urgent recognition and treatment to minimise morbidity and mortality, little is known about prehospital practitioners' knowledge of the condition. Aims: This study aimed to assess UK prehospital practitioners' knowledge of recognition, treatment and risks of heat-related illness. Methods: An online questionnaire was disseminated to UK prehospital practitioners. Findings and conclusions: Some aspects, such as the criteria for diagnosis and the need for urgent treatment were generally well known. Other areas, such as risk of mortality and risk of complications and organ dysfunction, were less well known. Further education and awareness of this condition may be warranted. [ABSTRACT FROM AUTHOR]

With global warming, extreme environmental heat is becoming a social issue of concern, which can cause adverse health results including heatstroke (HS). Severe heat stress is characterized by cell death of direct heat damage, excessive inflammatory responses, and coagulation disorders that can lead to multiple organ dysfunction (MODS) and even death. However, the significant pathophysiological mechanism and treatment of HS are still not fully clear. Various modes of cell death, including apoptosis, pyroptosis, ferroptosis, necroptosis and PANoptosis are involved in MODS induced by heatstroke. In this review, we summarized molecular mechanism, key transcriptional regulation as for HSF1, NRF2, NF-κB and PARP-1, and potential therapies of cell death resulting in CNS, liver, intestine, reproductive system and kidney injury induced by heat stress. Understanding the mechanism of cell death provides new targets to protect multi-organ function in HS. [ABSTRACT FROM AUTHOR]

This retrospective multicenter study was conducted across 83 intensive care units (ICUs) in 16 cities in Sichuan, China. Critically ill patients diagnosed with heatstroke and lung infections were included in the study. Specimens from the lower respiratory tract were collected for microbiological testing, and the characteristics of the pathogens were described. A total of 462 patients diagnosed with heatstroke-related pulmonary infections were included, 134 patients (29.0%) tested positive for respiratory pathogens. The most frequently isolated strain was Klebsiella pneumoniae (34.3%), followed by Escherichia coli (28.4%), Staphylococcus aureus (20.9%). The results revealed that in the hyperthermic resistance group, there was a higher proportion of Pseudomonas aeruginosa [14(34.1%) vs 11(11.8%), p=0.002] and Stenotrophomonas maltophilia [4(9.8%) vs 1(1.1%), p=0.030] compared to the hyperthermic control group. And a higher proportion of Staphylococcus aureus [27(29.7%) vs 1(2.3%), p

Background: Brain injury often results in high mortality rates and significant sequelae following severe heatstroke (HS). Neuroinflammation aggravates HS-induced brain injury, yet the involvement of microglia in heat-induced neuroinflammation deserves further investigation. Methods: Our study investigated activation status, phenotype markers, production of pro-inflammatory cytokine and reactive oxygen species (ROS) of microglia both in vitro and in vivo under HS. Utilizing high-throughput sequencing, we identified SIRT1 as a potential modulator of microglia phenotype, and observed that SIRT1 alleviated severe heatstroke-induced brain injury following intraperitoneal administration of the SIRT1 agonist SRT-1720 and the inhibitor selisistat. Additionally, the effects of SRT-1720 and selisistat on mitochondrial dynamics and microglial phenotype transition were examined in BV2 cells in vitro. Results: Heatstroke promotes microglia activation, as evidenced by the increased production of pro-inflammatory cytokine and reactive oxygen species. High-throughput sequencing revealed elevated expression of SIRT1 in BV2 cells under HS. Upon inhibition of SIRT1 expression, there was a corresponding increase in pro-inflammatory cytokine, iNOS, and ROS expression in BV2 cells. In vivo experiments with the SIRT1 agonist SRT-1720 showed a mitigation of neuron injury under HS, as assessed by Nissl and HE staining. Activation of SIRT1 was associated with a reduction in mitochondrial injury and a decrease in the phosphorylation of mitochondrial fission protein Drp1ser616. Furthermore, the heat-induced activation of microglia was reversed by the Drp1 inhibitor, Mdivi. Conclusions: Our findings provided evidence that SIRT1 played a crucial role in inhibiting heat stress-induced microglial activation. By suppressing the phosphorylation of mitochondrial fission protein Drp1, SIRT1 contributed to the reduction of neuroinflammation and severity of heatstroke-induced brain injury.

BackgroundThe prevalence of heatstroke is rising due to global warming, making it a serious but preventable condition, highlighting the urgent need for effective dissemination of relevant health education to the general public. Advances in technology have made accessing health information more convenient and rapid. In recent years, short videos have become a primary medium for delivering health education, with TikTok gaining considerable popularity among the general public. However, the quality of heatstroke-related health education content on TikTok deserves closer scrutiny.ObjectiveThis study aimed to evaluate the quality and content of heatstroke-related videos available on TikTok.MethodsThe present study analyzed the top 100 heatstroke-related short videos on TikTok, focusing on their characteristics, quality, and the content they conveyed. The quality of these videos was assessed using the DISCERN instrument. In addition, the completeness of the videos was assessed by examining six key aspects: disease definition, clinical manifestations, risk factors, assessment, management, and outcomes.ResultsThe study included a total of 90 videos. The results showed that news organizations and healthcare professionals were the primary contributors to these videos, with those from news organizations receiving the most attention. In contrast, those from healthcare professionals received comparatively less engagement. Overall, the quality of the information was found to be moderately low, with the highest quality videos posted by non-profit organizations, followed by those posted by healthcare professionals. The majority of videos uploaded described the disease definition, clinical presentation, risk factors, assessment, management, and outcomes of heatstroke.ConclusionThe quality of information provided in heatstroke-related short videos on TikTok is generally inadequate and requires significant improvement. In addition, such content should be subject to government review to ensure its accuracy and reliability.

Xiao-xiao Ni,1,&ast; Zhe-ying Liu,2,&ast; Yan-yan Zeng,1,&ast; Zhi-feng Liu2 1Department of Hyperbaric Oxygen Medicine and Rehabilitation, General Hospital of Southern Theater Command of PLA, Guangzhou, Guangdong, People’s Republic of China; 2Department of Medicine Intensive Care Unit, General Hospital of Southern Theater Command of PLA, Guangzhou, Guangdong, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Zhi-feng Liu, Department of Medicine Intensive Care Unit, General Hospital of Southern Theatre Command of PLA, Guangzhou, Guangdong, People’s Republic of China, Email Zhifengliu7797@163.comBackground: Hyperthermia and multiple organ dysfunction syndrome (MODS) are the main characteristics of heatstroke and COVID-19. Differentiating between these illnesses is crucial during a summer COVID-19 pandemic, but cases of heatstroke comorbid with COVID-19 are rarely reported.Case description: We report the first case of heatstroke comorbid with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection in a 52-year-old male. After receiving intravenous antibiotics, organ protection measures, and treatment for coagulation disorders, his fever and coma resolved. However, he developed dyspnea and cerebral hemorrhage after several days. This patient experienced a multi-pathogen pulmonary infection and an intractable coagulopathy that ultimately resulted in MODS and death.Conclusion: The combination of heatstroke and SARS-CoV-2 infection exacerbated inflammation, immune abnormalities, and coagulation disorders. The interaction between inflammation and coagulation disturbances contributed to the underlying mechanism in this case, highlighting the importance of early anti-infection, treatment for coagulopathy, immune regulation, and organ protection as crucial interventions.Keywords: heatstroke, COVID‐19, infection, coagulation disorder, cerebral hemorrhage

Purpose: In patients with heatstroke, disseminated intravascular coagulation (DIC) is associated with greater risk of in-hospital mortality. However, time-consuming assays or a complex diagnostic system may delay immediate treatment. Therefore, the present study proposes a new heatstroke-induced coagulopathy (HIC) score in patients with heat illness as an early warning indicator for DIC. Methods: This retrospective study enrolled patients with heat illness in 24 Chinese hospitals from March 2021 to May 2022. Patients under 18 years old, with a congenital clotting disorder or liver disease, or using anticoagulants were excluded. Data were collected on demographic characteristics, routine blood tests, conventional coagulation assays and biochemical indexes. The risk factors related to coagulation function in heatstroke were identified by regression analysis, and used to construct a scoring system for HIC. The data of patients who met the diagnostic criteria for HIC and International Society on Thrombosis and Haemostasis defined-DIC were analyzed. All statistical analyses were performed using SPSS 26.0. Results: The final analysis included 302 patients with heat illness, of whom 131 (43.4%) suffered from heatstroke, including 7 death (5.3%). Core temperature (OR = 1.681, 95% CI 1.291 − 2.189, p

To explore the National Fatality Review Case Reporting System (NFR-CRS) as a new data source to (1) characterize pediatric vehicular heatstroke (PVH) deaths among children <15 years of age reviewed by Child Death Review teams, and (2) identify factors independently associated with common PVH scenarios and incident locations. Data for 2005–2019 were used to characterize 296 PVH deaths. Frequencies and percentages were calculated to describe child, supervisor, and incident characteristics. Multiple logistic regression with and without imputation were carried out to identify factors associated with the two outcomes of interest: PVH scenario (left in vehicle vs. gained access) and incident place (supervisor workplace vs. other locations). Odds ratios and 95% confidence intervals (OR, 95% CI) were calculated. Most children had been left unattended in vehicles (N = 225, 76.0%) and 13.5% (N = 40) had gained access independently. Children were most often male (N = 168, 56.8%), non-Hispanic White (N = 131, 44.3%), and <2 years of age (N = 172, 58.1%). Disability or chronic illness was noted for 4.7% (N = 14), 13.9% (N = 41) had a history of maltreatment, and 6.1% (N = 18) an open CPS case at the time of incident. Children left unattended were more likely to be <2 years of age (adjusted imputed OR 26.7, CI 7.3–97.2) and less likely to have an open CPS case (0.2, 0.0–0.4) and for the incident to occur at home (0.2, 0.1–0.9) compared to children who gained access. PVH deaths occurring at the supervisor's workplace were more likely to be <2 years of age (6.2, 2.4–15.8), to have occurred on a weekday (5.9, 1.7–20.9), and to have been supervised by their parent at the incident time (2.7, 1.1–6.7) compared to other locations. The results align with previous PVH findings and added new information on child race/ethnicity, CPS action, disability/chronic illness, and maltreatment. With the exception of parents being more likely to be the supervisor in incidents occurring at home, which was expected, neither supervisor characteristics nor child race/ethnicity or sex were independently significant in multiple regression, suggesting that PVH is pervasive and that education campaigns should be similarly broad. [ABSTRACT FROM AUTHOR]

Rhabdomyolysis (RM) induced by electric blankets is exceedingly rare, with only three cases identified in our literature review. Both RM and Guillain--Barré syndrome (GBS) present with similar clinical manifestations of myalgia and muscle weakness, posing a potential challenge for accurate diagnosis in clinical settings. This report presents the case of a 22-year-old man who developed RM subsequent to the use of an electric blanket. Despite undergoing plasma exchange and renal replacement therapy, the patient continued to exhibit poor muscle strength in both lower limbs. Subsequent comprehensive evaluation revealed the presence of concurrent GBS. Following a 5-day course of intravenous gamma globulin treatment, the patient experienced rapid recovery of muscle strength and was discharged. Additionally, we reviewed seven cases from the literature of coexistent RM and GBS. This indicated that investigation of the timing of onset of muscle strength decline in RM patients could help to identify potential concurrent neurological or muscular disorders. In cases in which concurrent GBS and RM cannot be definitively ascertained during early hospitalization, prioritizing plasma exchange treatment may lead to improved patient outcomes. [ABSTRACT FROM AUTHOR]

In patients with heatstroke, disseminated intravascular coagulation (DIC) is associated with greater risk of in-hospital mortality. However, time-consuming assays or a complex diagnostic system may delay immediate treatment. Therefore, the present study proposes a new heatstroke-induced coagulopathy (HIC) score in patients with heat illness as an early warning indicator for DIC. This retrospective study enrolled patients with heat illness in 24 Chinese hospitals from March 2021 to May 2022. Patients under 18 years old, with a congenital clotting disorder or liver disease, or using anticoagulants were excluded. Data were collected on demographic characteristics, routine blood tests, conventional coagulation assays and biochemical indexes. The risk factors related to coagulation function in heatstroke were identified by regression analysis, and used to construct a scoring system for HIC. The data of patients who met the diagnostic criteria for HIC and International Society on Thrombosis and Haemostasis defined-DIC were analyzed. All statistical analyses were performed using SPSS 26.0. The final analysis included 302 patients with heat illness, of whom 131 (43.4%) suffered from heatstroke, including 7 death (5.3%). Core temperature (OR = 1.681, 95% CI 1.291 − 2.189, p < 0.001), prothrombin time (OR = 1.427, 95% CI 1.175 − 1.733, p < 0.001) and D-dimer (OR = 1.242, 95% CI 1.049 − 1.471, p = 0.012) were independent risk factors for heatstroke, and therefore used to construct an HIC scoring system because of their close relation with abnormal coagulation. A total score ≥ 3 indicated HIC, and HIC scores correlated with the score for International Society of Thrombosis and Hemostasis -DIC (r = 0.8848, p < 0.001). The incidence of HIC (27.5%) was higher than that of DIC (11.2%) in all of 131 heatstroke patients. Meanwhile, the mortality rate of HIC (19.4%) was lower than that of DIC (46.7%). When HIC developed into DIC, parameters of coagulation dysfunction changed significantly: platelet count decreased, D-dimer level rose, and prothrombin time and activated partial thromboplastin time prolonged (p < 0.05). The newly proposed HIC score may provide a valuable tool for early detection of HIC and prompt initiation of treatment. [ABSTRACT FROM AUTHOR]

IntroductionHeatstroke is a serious clinical condition caused by exposure to high temperature and high humidity environment, which leads to a rapid increase of the core temperature of the body to more than 40°C, accompanied by skin burning, consciousness disorders and other organ system damage. This study aims to analyze the effect of meteorological factors on the incidence of heatstroke using machine learning, and to construct a heatstroke forecasting model to provide reference for heatstroke prevention.MethodsThe data of heatstroke incidence and meteorological factors in a city in South China from May to September 2014–2019 were analyzed in this study. The lagged effect of meteorological factors on heatstroke incidence was analyzed based on the distributed lag non-linear model, and the prediction model was constructed by using regression decision tree, random forest, gradient boosting trees, linear SVRs, LSTMs, and ARIMA algorithm.ResultsThe cumulative lagged effect found that heat index, dew-point temperature, daily maximum temperature and relative humidity had the greatest influence on heatstroke. When the heat index, dew-point temperature, and daily maximum temperature exceeded certain thresholds, the risk of heatstroke was significantly increased on the same day and within the following 5 days. The lagged effect of relative humidity on the occurrence of heatstroke was different with the change of relative humidity, and both excessively high and low environmental humidity levels exhibited a longer lagged effect on the occurrence of heatstroke. With regard to the prediction model, random forest model had the best performance of 5.28 on RMSE and dropped to 3.77 after being adjusted.DiscussionThe incidence of heatstroke in this city is significantly correlated with heat index, heatwave, dew-point temperature, air temperature and zhongfu, among which the heat index and dew-point temperature have a significant lagged effect on heatstroke incidence. Relevant departments need to closely monitor the data of the correlated factors, and adopt heat prevention measures before the temperature peaks, calling on citizens to reduce outdoor activities.

Purpose: The incidence of heatstroke (HS) is not particularly high; however, once it occurs, the consequences are serious. It is reported that calcitonin gene-related peptide (CGRP) is protective against brain injury in HS rats, but detailed molecular mechanisms need to be further investigated. In this study, we further explored whether CGRP inhibited neuronal apoptosis in HS rats via protein kinase A (PKA)/p-cAMP response element-binding protein (p-CREB) pathway. Methods: We established a HS rat model in a pre-warmed artificial climate chamber with a temperature of (35.5 ± 0.5) °C and a relative humidity of 60% ± 5%. Heatstress was stopped once core body temperature reaches above 41 °C. A total of 25 rats were randomly divided into 5 groups with 5 animals each: control group, HS group, HS+CGRP group, HS+CGRP antagonist (CGRP8-37) group, and HS+CGRP+PKA/p-CREB pathway blocker (H89) group. A bolus injection of CGRP was administered to each rat in HS+CGRP group, CGRP8-37 (antagonist of CGRP) in HS+CGRP8-37 group, and CGRP with H89 in HS+CGRP+H89 group. Electroencephalograms were recorded and the serum concentration of S100B, neuron-specific enolase (NSE), neuron apoptosis, activated caspase-3 and CGRP expression, as well as pathological morphology of brain tissue were detected at 2 h, 6 h, and 24 h after HS in vivo. The expression of PKA, p-CREB, and Bcl-2 in rat neurons were also detected at 2 h after HS in vitro. Exogenous CGRP, CGRP8-37, or H89 were used to determine whether CGRP plays a protective role in brain injury via PKA/p-CREB pathway. The unpaired t-test was used between the 2 samples, and the mean ± SD was used for multiple samples. Double-tailed p

Worldwide gatherings at religious festivals raise the possibility of disease transmission among attendees and the local populace. The enormous gathering of pilgrims may impact the country's health system. Infectious diseases with epidemic characteristics threaten global health security, demonstrating the significance of preparedness for any public health catastrophe. This literature review describes the extensive neurological disorders related to hajj pilgrims and the importance of preventive methods to control these diseases. Our systematic review was conducted from many sources, including credible websites and journals. We found about 23 articles about the most common neurological disease in hajj pilgrims. A clear result was observed about increased incidents of meningitis as a global health neurological disease related to hajj pilgrims of total PubMed indexed publications studies, and one review article was done in 2019. This review study summarizes the neurological health challenge from infectious, non-infectious to stroke mimics presentation and the heatstroke prevalence in Hajj and the process of how the body adaption to heat stress may influence the body systems and brain function to be reported the most common presentation may mimic to a neurological cause

Heatstroke induces fluid loss and electrolyte abnormalities owing to high ambient temperature (AT) and relative humidity (RH). Aquaporin 1 (AQP1) is a key protein for water homeostasis; however, its role in heatstroke remains unclear. This study examines endothelial AQP1 in Tie2-Cre/LNL-AQP1 double transgenic (dTG) mice with upregulated Aqp1 in endothelial cells. For experimental heatstroke, mice were exposed to 41 °C AT and >99% RH. Blood, brain, kidney, and liver samples were collected 24 h later. Blood was analyzed for electrolytes and tissue damage markers, and organs were examined using morphological and immunohistological staining for 3-nitrotyrosine (3-NT), AQP1, and Iba-1. No difference in Aqp1 expression was observed in the whole brain; however, it was detected in dTG mice after capillary deprivation. AQP1 immunostaining revealed immunoreaction in blood vessels. After heat exposure, wild-type and dTG mice showed electrolyte abnormalities compared with non-heatstroke wild-type mice. Hepatic damage markers were significantly higher in dTG mice than in wild-type mice. Hematoxylin–eosin staining and 3-NT immunoreactivity in the liver indicated hepatic damage. The number of Iba-1-positive cells adherent to hepatic vasculature was significantly higher in dTG mice than in wild-type mice. This study is the first to suggest that endothelial AQP1 contributes to hepatic damage after heatstroke.

Background and objectiveHeatstroke (HS) is a life-threatening condition resulting from thermal injury within the body, and it is associated with a significantly high mortality rate. This study aimed to assess the knowledge, attitudes and practices (KAP) among the general community population toward heatstroke.MethodsThe web-based cross-sectional study was conducted between September 2023 and October 2023 at the Emergency Department of Dongyang People's Hospital. A self-designed questionnaire was developed to collect demographic information of the general community population and to assess their knowledge, attitudes and practices toward heatstroke.ResultsA total of 1,356 valid questionnaires were collected. Among the participants, 875 (64.53%) were female, and 496 (36.58%) had regular exercise. The mean knowledge, attitudes and practices scores were 12.73 ± 1.42 (possible range: 0–14), 33.74 ± 2.91 (possible range: 8–40) and 34.65 ± 5.30 (possible range: 8–40), respectively. The structural equation model demonstrated that education had direct effects on knowledge (β = 0.017, p < 0.001), attitudes (β = 0.123, p < 0.001), and practices (β = −0.094, p < 0.001). Moreover, knowledge had direct effects on attitudes (β = 1.920, p < 0.001), and attitudes had direct effects on practices (β = 0.642, p < 0.001).ConclusionThe findings revealed that the general community population have sufficient knowledge, active attitudes and proactive practices toward the heatstroke. However, there is still room for improvement and it is necessary to develop and implement educational initiatives and interventions designed to further enhance their KAP toward heatstroke.

BackgroundAn increase in Heatstroke cases occurred in southwest China in 2022 due to factors like global warming, abnormal temperature rise, insufficient power supply, and other contributing factors. This resulted in a notable rise in Heatstroke patients experiencing varying degrees of organ dysfunction. This descriptive study aims to analyze the epidemiology and clinical outcomes of Heatstroke patients in the ICU, providing support for standardized diagnosis and treatment, ultimately enhancing the prognosis of Heatstroke.MethodsA retrospective, multicenter, descriptive analysis was conducted on Heatstroke patients admitted to ICUs across 83 hospitals in southwest China. Electronic medical records were utilized for data collection, encompassing various aspects such as epidemiological factors, onset symptoms, complications, laboratory data, concurrent infections, treatments, and patient outcomes.ResultsThe dataset primarily comprised classic heatstroke, with 477 males (55% of total). The patient population had a median age of 72 years (range: 63–80 years). The most common initial symptoms were fever, mental or behavioral abnormalities, and fainting. ICU treatment involved respiratory support, antibiotics, sedatives, and other interventions. Among the 700 ICU admissions, 213 patients had no infection, while 487 were diagnosed with infection, predominantly lower respiratory tract infection. Patients presenting with neurological symptoms initially (n = 715) exhibited higher ICU mortality risk compared to those without neurological symptoms (n = 104), with an odds ratio of 2.382 (95% CI 1.665, 4.870) (p = 0.017).ConclusionIn 2022, the majority of Heatstroke patients in southwest China experienced classical Heatstroke, with many acquiring infections upon admission to the ICU. Moreover, Heatstroke can result in diverse complications.

The occurrence of sequelae is common after heatstroke. There is a lack of risk prediction data regarding the prevalence of sequelae. This study aims to develop a predictive model for the sequelae after heatstroke, including cerebellar dysfunction. Heatstroke patients admitted to our hospital in the past 8 years were retrospectively enrolled. Regression analyses were conducted to identify risk factors associated with sequelae and cerebellar dysfunction. A prediction model for post-heatstroke sequelae was developed and internally and externally validated. Twenty-three percent of the patients experienced sequelae, with cerebellar dysfunction accounting for 51.7%. Patients with sequelae had longer duration of hyperthermia and coma, lower Glasgow Coma Scales scores, elevated core temperature, increased incidence of multiple organ dysfunction upon admission, and a worse prognosis compared to non-sequelae patients. Patients with cerebellar injury exhibited impaired balance, and a Sepsis-related Organ Failure Assessment (SOFA) score > 5 is an independent risk factor. The prediction system included advanced age, coma, and an APACHE-II score > 10 upon admission, predicting sensitivity = 0.8966, specificity = 0.8925, and AUC of ROC curve = 0.941 (95% CI: 0.884 ~ 0.976). The C-index in the internal verification was 0.942 (95% CI: 0.847 ~ 0.981) and the AUC in the external verification was 0.816 (95% CI: 0.699 ~ 0.902). The prediction system included advanced age, coma, and higher APACHE-II scores as variables, indicating a significant prevalence of sequelae. Higher SOFA scores were associated with the increased occurrence of cerebellar dysfunction and balance impairment. The prediction system could better predict sequelae after heatstroke. [ABSTRACT FROM AUTHOR]

Many oil and gas extraction (OGE) activities occur in high-heat environments, resulting in a significant risk of heat-related illness among outdoor workers in this industry. This report highlights cases of occupational heat-related illness that resulted in death and identifies common risk factors for heat-related fatalities and hospitalizations among OGE workers. Two databases maintained by the National Institute for Occupational Safety and Health (NIOSH) and the Occupational Safety and Health Administration (OSHA) were reviewed to identify heat-related fatalities, hospitalizations, and associated risk factors among OGE workers. Nine fatalities and associated risk factors were identified during 2014–2019 from NIOSH's Fatalities in Oil and Gas Extraction (FOG) Database. Risk factors identified included those commonly associated with heat-related fatalities: new workers not acclimatized to heat, inadequate heat stress training, and underlying hypertension or cardiovascular disease. Of particular note, substance use was identified as a significant risk factor as more than half of the fatalities included a positive postmortem test for amphetamines or methamphetamines. Fifty heat-related hospitalizations were identified from OSHA's Severe Injury Report Database during January 2015–May 2021. Heat stress has been and will continue to be an important cause of fatality and adverse health effects in OGE as hot outdoor working conditions become more common and extreme. More emphasis on heat stress training, acclimatization regimens, medical screening, and implementation of workplace-supportive recovery programs may reduce heat-related fatalities and injuries in this industry. [ABSTRACT FROM AUTHOR]

Annual rates of heat illness and heat-related deaths have been increasing across the United States as more regions of the country have been experiencing heat waves of extreme ambient temperatures of prolonged durations. According to the Centers for Disease Control and Prevention, heat illnesses have become the leading cause of weather-related deaths. This article critiques and describes the findings of a systematic review by C. Rublee et al. (2021). The review was conducted to develop an evidence-based algorithm specific for management of heatstroke in the emergency department with implications for improving recognition, initiating rapid cooling, and providing supportive care to reduce patient mortality and morbidity. [ABSTRACT FROM AUTHOR]

The incidence of heatstroke (HS) is not particularly high; however, once it occurs, the consequences are serious. It is reported that calcitonin gene-related peptide (CGRP) is protective against brain injury in HS rats, but detailed molecular mechanisms need to be further investigated. In this study, we further explored whether CGRP inhibited neuronal apoptosis in HS rats via protein kinase A (PKA)/p-cAMP response element-binding protein (p-CREB) pathway. We established a HS rat model in a pre-warmed artificial climate chamber with a temperature of (35.5 ± 0.5) °C and a relative humidity of 60% ± 5%. Heatstress was stopped once core body temperature reaches above 41 °C. A total of 25 rats were randomly divided into 5 groups with 5 animals each: control group, HS group, HS+CGRP group, HS+CGRP antagonist (CGRP8-37) group, and HS+CGRP+PKA/p-CREB pathway blocker (H89) group. A bolus injection of CGRP was administered to each rat in HS+CGRP group, CGRP8-37 (antagonist of CGRP) in HS+CGRP8-37 group, and CGRP with H89 in HS+CGRP+H89 group. Electroencephalograms were recorded and the serum concentration of S100B, neuron-specific enolase (NSE), neuron apoptosis, activated caspase-3 and CGRP expression, as well as pathological morphology of brain tissue were detected at 2 h, 6 h, and 24 h after HS in vivo. The expression of PKA, p-CREB, and Bcl-2 in rat neurons were also detected at 2 h after HS in vitro. Exogenous CGRP, CGRP8-37, or H89 were used to determine whether CGRP plays a protective role in brain injury via PKA/p-CREB pathway. The unpaired t -test was used between the 2 samples, and the mean ± SD was used for multiple samples. Double-tailed p < 0.05 was considered statistically significant. Electroencephalogram showed significant alteration of θ (54.50 ± 11.51 vs. 31.30 ± 8.71, F = 6.790, p = 0.005) and α wave (16.60 ± 3.21 vs. 35.40 ± 11.28, F = 4.549, p = 0.020) in HS group compared to the control group 2 h after HS. The results of triphosphate gap terminal labeling (TUNEL) showed that the neuronal apoptosis of HS rats was increased in the cortex (9.67 ± 3.16 vs. 1.80 ± 1.10, F = 11.002, p = 0.001) and hippocampus (15.73 ± 8.92 vs. 2.00 ± 1.00, F = 4.089, p = 0.028), the expression of activated caspase-3 was increased in the cortex (61.76 ± 25.13 vs. 19.57 ± 17.88, F = 5.695, p = 0.009) and hippocampus (58.60 ± 23.30 vs. 17.80 ± 17.62, F = 4.628, p = 0.019); meanwhile the expression of serum NSE (5.77 ± 1.78 vs. 2.35 ± 0.56, F = 5.174, p = 0.013) and S100B (2.86 ± 0.69 vs. 1.35 ± 0.34, F = 10.982, p = 0.001) were increased significantly under HS. Exogenous CGRP decreased the concentrations of NSE and S100B, and activated the expression of caspase-3 (0.41 ± 0.09 vs. 0.23 ± 0.04, F = 32.387, p < 0.001) under HS; while CGRP8-37 increased NSE (3.99 ± 0.47 vs. 2.40 ± 0.50, F = 11.991, p = 0.000) and S100B (2.19 ± 0.43 vs. 1.42 ± 0.30, F = 4.078, p = 0.025), and activated the expression caspase-3 (0.79 ± 0.10 vs. 0.23 ± 0.04, F = 32.387, p < 0.001). For the cell experiment, CGRP increased Bcl-2 (2.01 ± 0.73 vs. 2.15 ± 0.74, F = 8.993, p < 0.001), PKA (0.88 ± 0.08 vs. 0.37 ± 0.14, F = 20.370, p < 0.001), and p-CREB (0.87 ± 0.13 vs. 0.29 ± 0.10, F = 16.759, p < 0.001) levels; while H89, a blocker of the PKA/p-CREB pathway reversed the expression. CGRP can protect against HS-induced neuron apoptosis via PKA/p-CREB pathway and reduce activation of caspase-3 by regulating Bcl-2. Thus CGRP may be a new target for the treatment of brain injury in HS. [ABSTRACT FROM AUTHOR]

Background: Central nervous system (CNS) injury is the most prominent feature of heatstroke and the hippocampus is prone to damage. However, the mechanisms underlying the heatstroke-induced hippocampal injury remain unclear. Hyperbaric oxygen (HBO) therapy prevents CNS injury in heatstroke mice. However, the underlying mechanisms of HBO in heatstroke-induced hippocampal injury remain unclear. This study aimed to elucidate the protective effects of HBO against hippocampal injury and its potential role in microglial pyroptosis in heatstroke rats.Methods: A rat heatstroke model and a heat stress model with a mouse microglial cell line (BV2) were, respectively, used to illustrate the effect of HBO on heat-induced microglial pyroptosis in vivo and in vitro. We used a combination of molecular and histological methods to assess microglial pyroptosis and neuroinflammation both in vivo and in vitro.Results: The results revealed that HBO improved heatstroke-induced survival outcomes, hippocampal injury, and neurological dysfunction in rats. In addition, HBO mitigates microglial pyroptosis and reduces the expression of pro-inflammatory cytokines in the hippocampus of heatstroke rats. In vitro experiments showed that HBO attenuated BV2 cell injury under heat stress. Furthermore, HBO prevented heat-induced pyroptosis of BV2 cells, and the expression of pro-inflammatory cytokines IL-18 and IL-1β was reduced. Mechanistically, HBO alleviates heatstroke-induced neuroinflammation and hippocampal injury by preventing microglial pyroptosis. Conclusions: In conclusion, HBO attenuates heatstroke-induced neuroinflammation and hippocampal injury by inhibiting microglial pyroptosis. [ABSTRACT FROM AUTHOR]

Objective To explore the the effect and possible mechanism of heat stress at different rewarming time on the damage of human skeletal muscle cells (HSKMC). Methods HSKMC in the logarithmic growth phase were divided into the heat stress group and control group. Cells in the control group were cultured normally, and the heat stress models were established in the heat stress group and then were rewarmed in 37 ℃ and 5% CO2 cell incubator for 0, 6, 12 and 24 h, respectively. The cell survival rate was detected by CCK-8, the cell ultrastructure was observed by transmission electron microscopy, TRPV4 protein was detected by Western blotting, and TRPV4 mRNA was detected by real-time fluorescence quantitative PCR. HSKMC in the logarithmic growth phase were randomly divided into the HS group, GSK+HS group, HC+HS group, and NC group. Cells in the NC group were cultured normally, and the heat stress models were established in the other three groups, and the rewarming time was 12 h. Cells in the GSK+HS group and HC+HS group were given TRPV4 agonist GSK1016790A (500 nmol) and TRPV4 inhibitor HC-067047(5 µmol) at 0. 5 h before heat stress, and Ca2+ level was detected by flow cytometry. Results Compared with the control group, the survival rate of cells in heat stress group decreased after rewarming for 0, 6, 12 and 24 h (P<0. 05). With the extension of rewarming time, the survival rate of cells in the heat stress group decreased successively, and significant difference was found between these two groups (all P<0. 05). Compared with the control group, ultrastructural changes were observed in the cells in the heat stress group after rewarming for 0 and 6 h, which were mainly manifested as cell swelling, enlarged volume, cytoplasmic vacuolation, obvious mitochondrial swelling, degranulation, double ridge loss, widening of perinuclear space, nucleus condensation and contraction, and interruption of some envelope continuity. After rewarming for 12 and 24 h, the cells in the heat stress group even showed nucleolysis and disappearance, nucleus fragmentation, chromatin boundary aggregation, and cytoplasmic structure disintegration and granulation. Compared with the control group, the relative expression levels of TRPV4 mRNA and protein in heat stress group increased after rewarming for 0, 6, 12 and 24 h (all P<0. 05). The levels of intracellular Ca2+ in the NC group, HC+HS group, HS group and GSK+HS group increased successively, and significant difference was found between groups (all P<0. 05). Conclusions Heat stress can reduce HSKMC survival rate and damage HSKMC structure. The longer rewarming time after heat stress, the greater the damage to HSKMC cells. The mechanism may be related to the promotion of TRPV4 expression and its mediated Ca2+ influx. [ABSTRACT FROM AUTHOR]