Zhengyuan Xia

The University of Hong Kong | HKU · Department of Medicine

The activity of phosphatase and tensin homolog (PTEN) can be inhibited by miR-17-3p, which results in attenuating myocardial ischemia/reperfusion injury (IRI), however, the mechanism behind this phenomenon is still elusive. Suppression of PTEN leads to augmented protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling strength and cons...

BACKGROUND Diabetes augments activity of histone deacetylase 6 (HDAC6) and generation of tumor necrosis factor α (TNFα) and impairs the physiological function of mitochondrial complex I (mCI) which oxidizes reduced nicotinamide adenine dinucleotide (NADH) to nicotinamide adenine dinucleotide to sustain the tricarboxylic acid cycle and β-oxidation....

Acute lung injury (ALI) represents a frequent sepsis-induced inflammatory disorder. Mesenchymal stromal cells (MSCs) elicit anti-inflammatory effects in sepsis. This study investigated the mechanism of exosomes from adipose-derived MSCs (ADMSCs) in sepsis-induced ALI. The IL-27r −/− (WSX-1 knockout) or wild-type mouse model of sepsis was establishe...

Diabetes patients with painful diabetic neuropathy (PDN) show severe spinal atrophy, suggesting pathological changes of the spinal cord contributes to central sensitization. However, the cellular changes and underlying molecular mechanisms within the diabetic spinal cord are less clear. By using a rat model of type 1 diabetes (T1D), we noted an ext...

Endothelial cells are highly sensitive to hemodynamic shear stresses, which act in the blood flow’s direction on the blood vessel’s luminal surface. Thus, endothelial cells on that surface are exposed to various physiological and pathological stimuli, such as disturbed flow-induced shear stress, which may exert effects on adaptive vascular diameter...

Abstract Background Abnormal myocardial Nav1.5 expression and function cause lethal ventricular arrhythmias during myocardial ischemia–reperfusion (I/R). Protein inhibitor of activated STAT Y (PIASy)-mediated caveolin-3 (Cav-3) SUMO modification affects Cav-3 binding to the voltage-gated sodium channel 1.5 (Nav1.5). PIASy activity is increased afte...

Background: We aimed to compare the analgesic effect and incidence of lower limb weakness of transmuscular quadratus lumborum (TQL) block via subfascial approach with that via extrafascial after laparoscopic cholecystectomy (LC). Methods: Eighty patients undergoing LC were randomized to receive ultrasound-guided bilateral TQL block via subfascia...

The literature is full of claims regarding the consumption of polyphenol or polyamine-rich foods that offer some protection from developing cardiovascular disease (CVD). This is achieved by preventing cardiac hypertrophy and protecting blood vessels through improving the function of endothelium. However, do these interventions work in the aged huma...

Growing evidence suggests that the interactions between astrocytes and neurons exert important functions in the central sensitization of the spinal cord dorsal horn in rodents with diabetes and neuropathic pain (DNP). However, it still remains unclear how signal transmission occurs in the spinal cord dorsal horn between astrocytes and neurons, espe...

Rationale: Peripheral nerve block is a traditional perioperative analgesic method for its precise pain control and low systemic toxicity. However, a single low dose of local anesthetic merely provides a few hours of analgesia, and high dose results in irreversible toxicity, whereas continuous infusion of anesthetics is expensive and complicated. Th...

Background: Ischemic postconditioning (IPostC) has been reported as a promising method for protecting against myocardial ischemia-reperfusion (MI/R) injury. Our previous study found that the infarct-limiting effect of IPostC is abolished in the heart of diabetes whose cardiac expression of DJ-1 (also called PARK7, Parkinsonism associated deglycase)...

Acute myocardial infarction is a leading cause of death worldwide, while restoration of blood flow to previously ischemic myocardium may lead to ischemia/reperfusion (I/R) injury. Accumulated evidence shows that microRNAs play important roles in cardiovascular diseases. However, the potential role of microRNA-503 (miR-503) in myocardial I/R injury...

Myocardial infarction is one of the primary causes of mortality in patients with coronary heart disease worldwide. Early treatment of acute myocardial infarction restores blood supply of ischemic myocardium and decreases the mortality risk. However, when the interrupted myocardial blood supply is recovered within a certain period of time, it causes...

Introduction Sepsis-induced apoptosis leads to lymphopenia including the decrease of CD4⁺ T cells thus favoring immunosuppression. Objectives Although epidermal growth factor receptor (EGFR) inhibitors significantly improve the survival rate of septic mice, the effect of EGFR on the function and metabolism of CD4⁺ T cells in sepsis remained unknow...

Background: Patients with diabetes are more vulnerable to myocardial ischemia/reperfusion injury (MIRI). Abnormal increases of cardiac Connexin43 (Cx43) were shown to be associated with a variety of pathological conditions including myocardial ischemia and diabetic cardiomyopathy, concomitant with various degrees of changes in autophagy. However,...

Background: Dynamic prediction of patient mortality risk in the ICU with time series data is limited due to high dimensionality, uncertainty in sampling intervals, and other issues. A new deep learning method, temporal convolution network (TCN), makes it possible to deal with complex clinical time series data in ICU. We aimed to develop and valida...

Chronic obstructive pulmonary disease (COPD) is a leading cause of death worldwide, which is usually caused by exposure to noxious particles or gases. Hydrogen sulfide (H2S), as an endogenous gasotransmitter, is involved in the pathogenesis of COPD, but its role in COPD is little known. To investigate the role of H2S in COPD, a rat model of COPD wa...

Bupivacaine (BP) is a commonly clinically used local anesthetic (LA). Current studies suggest that neurological complications are increased in diabetic patients after LA application, but the molecular mechanism is poorly understood. LA-induced autophagy and neuronal injury have been reported. We hypothesized that a high-glucose environment aggravat...

Background: Results from previous studies evaluating the effects of remote ischemic preconditioning (RIPC) on morbidity and mortality after cardiac surgery are inconsistent. This meta-analysis of randomized controlled trials (RCTs) aims to determine whether RIPC improves cardiac and renal outcomes in adults undergoing cardiac surgery. Methods: P...

Background: Administration of propofol, an intravenous anesthetic with antioxidant property, immediately at the onset of post-ischemic reperfusion (propofol postconditioning, P-PostC) has been shown to confer cardioprotection against ischemia-reperfusion injury, while the underlying mechanism remains incompletely understood. The FoxO transcription...

Objective Asthma is characterized by airway hyperresponsiveness(AHR), inflammation and remodeling. Autophagy and endoplasmic reticulum stress(ERS) are dysregulated in asthma, and ATG5 has attracted wide attentions a representative gene of autophagy. Previous evidence shows that acupuncture may treat asthma by regulating the immune environment.Howev...

The mortality rate of young female COVID-19 patients is reported to be lower than that of young males but no significant difference in mortality was found between female and male COVID-19 patients aged over 65 years, and the underlying mechanism is unknown. We retrospectively analyzed clinical characteristics and outcomes of severely ill pre- and p...

The morbidity and mortality of sepsis‐induced acute kidney injury (SAKI) remain high. Early detection using molecular ultrasound imaging may reduce mortality and improve the prognosis. Inspired by the intrinsic relationship between platelets and SAKI, platelet membrane‐coated hybrid microbubbles (Pla‐MBs) are designed for early recognition of SAKI....

Coronavirus disease-2019 (COVID-19) has rapidly spread worldwide and causes high mortality of elderly patients. High-flow nasal cannula therapy (HFNC) is an oxygen delivery method for severely ill patients. We retrospectively analyzed the course of illness and outcomes in 110 elderly COVID-19 patients (≥65 years) treated with HFNC from 6 hospitals....

Background and aims: Screening for hepatopulmonary syndrome in cirrhotic patients is limited due to the need to perform contrast enhanced echocardiography (CEE) and arterial blood gas (ABG) analysis. We aimed to develop a simple and quick method to screen for the presence of intrapulmonary vascular dilation (IPVD) using noninvasive and easily avai...

IntroductionCatheter management strategies for suspected catheter-related bloodstream infection (CRBSI) remain a major challenge in intensive care units (ICUs). The objective of this study was to determine the incidence, risk factors, and mortality attributable to CRBSIs in those patients.MethodsA population-based surveillance on suspected CRBSI wa...

Background: This study attempted to investigate the impact of hepatopulmonary syndrome (HPS) on postoperative outcomes in hepatitis B virus-induced hepatocellular carcinoma (HBV-HCC) patients. Methods: HBV-HCC patients undergoing primary curative hepatectomy for HCC in our hospital were diagnosed with HPS by contrast-enhanced echocardiography (C...

Background Cardiac fatty acid metabolism is essential for maintaining normal cardiac function at baseline and in response to various disease stress, like diabetes. EP4 is widely expressed in cardiomyocytes and has been demonstrated to play a role in cardio function. However, its function in regulating cardiac fatty acid metabolism is remained unkno...

AimsDiabetic cardiomyopathy (DCM) is a specific myocardial alteration in patients with diabetics. LncRNA KCNQ1OT1 has been previously demonstrated to be involved in various diabetic complications. Our aims are to further investigate the underlying regulatory mechanisms/pathways of KCNQ1OT1 in DCM.Methods In vitro and in vivo models of DCM were esta...

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, which has lasted for nearly a year, has made people deeply aware of the strong transmissibility and pathogenicity of SARS-CoV-2 since its outbreak in December 2019. By December 2020, SARS-CoV-2 had infected over 65 million people globally, resulting in more than 1 million de...

Background: Telomere shortening and dysfunction may cause metabolic disorders, tissue damage and age-dependent pathologies. However, little is known about the association of telomere-associated protein Rap1 with mitochondrial energy metabolism and cardiac aging. Methods: Echocardiography was performed to detect cardiac structure and function in Rap...

microRNAs (miRs) are short, non-coding RNAs that regulate gene expression by mRNA degradation or translational repression. Accumulated studies have demonstrated that miRs participate in various biological processes including cell differentiation, proliferation, apoptosis, metabolism and development, and the dysregulation of miRs expression are invo...

Nuclear factor kappa B (NF-κB) activation contributes to many vascular inflammatory diseases. The present study tested the hypothesis that microRNA-17-3p (miR-17-3p) suppresses the pro-inflammatory responses via NF-κB signaling in vascular endothelium. Human umbilical vein endothelial cells (HUVECs), transfected with or without miR-17-3p agomir/ant...

Background Reduced levels of myocardial STAT3 activity in diabetic hearts may contribute to the increased susceptibility to ischemia-reperfusion injury (I/RI). The protein mammalian target of rapamycin (mTOR) can regulate metabolism and cell processes and plays major roles in the dynamics of I/RI. However, the role of mTOR in regulation of myocardi...

Bupivacaine has been widely used in clinical Anesthesia, but its neurotoxicity has been frequently reported, implicating cellular oxidative DNA damage as the major underlying mechanism. However, the mechanism underlying bupivacaine-induced oxidative DNA damage is unknown. We, thus, exposed SH-SY5Y cells to 1.5mM bupivacaine to induce neurotoxicity....

Endothelial cells are highly sensitive to hemodynamic shear stresses, which act in the blood flow’s direction on the blood vessel’s luminal surface. Endothelial cells on that surface, thusly, are exposed to various physiological and pathological stimuli, such as disturbed flow-induced shear stress, which may exert effects on adaptive vascular diame...

Hyperglycemia-induced oxidative stress plays important roles in the development of non-alcoholic fatty liver disease (NAFLD), which is a common complication in diabetic patients. The Nrf2-Keap1 pathway is important for cell antioxidant protection, while its role in exogenous antioxidant mediated protection against NAFLD is unclear. We thus, postula...

Background Oxidative stress enhances tumor invasion and metastasis in brain cancer. The activation of divalent metal transporter 1 (DMT1), which is regulated by glutamate receptors, can result in the increase of oxidative stress and risk of cancer development. Propofol, an anesthetic with antioxidant capacity, has been shown to decrease oxidative s...

The coronavirus disease 2019 (COVID-19) became a global pandemic. Males, compared to females, seem to be more susceptible to COVID-19, but related evidence is scarce, especially in severe patients. We explored sex differences in clinical characteristics and potential risk factors for mortality in severe COVID-19 patients. In this retrospective coho...

Background: Cerebral ischemic stroke is a refractory disease which seriously endangers human health. Remote ischemic perconditioning (RiPerC) by which the sublethal ischemic stimulus is administered during the ischemic event is beneficial after an acute stroke. However, the regulatory mechanism of RiPerC that relieves cerebral ischemic injury is s...

Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial lung disease characterized by chronic non-specific inflammation of the interstitial lung and extensive deposition of collagen fibers leading to destruction of lung function. Studies have demonstrated that exposure to fine particulate matter (PM2.5) increases the risk of IPF. In order...

Background: Perioperative cerebral hypoperfusion (CH) is common, although the underlying mechanism of cognitive impairment that results due to perioperative cerebral hypoperfusion remains to be determined. Isoflurane anesthesia induces neuronal injury via endoplasmic reticulum (ER) stress, whereas a sub-anesthetic dose of propofol improves postoper...

Background: Dynamic and precise estimation of blood loss (EBL) is quite important for perioperative management. To date, the Triton System, based on feature extraction technology (FET), has been applied to estimate intra-operative haemoglobin (Hb) loss but is unable to directly assess the amount of blood loss. We aimed to develop a method for the...

Vascular complications from diabetes often result in poor outcomes for patients, even after optimized interventions. Forkhead box protein O1 (FoxO1) is a key regulator of cellular metabolism and plays an important role in vessel formation and maturation. Alterations of FoxO1 occur in the cardiovascular system in diabetes, yet the role of FoxO1 in d...

Purpose: The lack of training in personal protective equipment (PPE) donning and doffing is hindering the current fight against the COVID-19 worldwide. In order to enable medical staff to learn how to don and doff PPE faster and more effectively, we compared two training methods of PPE donning and doffing. Methods: Participants in this study wer...

Abstract Background Long-term mechanical ventilation with hyperoxia can induce lung injury. General anesthesia is associated with a very high incidence of hyperoxaemia, despite it usually lasts for a relatively short period of time. It remains unclear whether short-term mechanical ventilation with hyperoxia has an adverse impact on or cause injury...

Background. Constitutive nuclear factor kappa B (NFκB) activation has been shown to exacerbate during myocardial ischemia/reperfusion (I/R) injury. We recently showed that miR-181c-5p exacerbated cardiomyocytes injury and apoptosis by directly targeting the 3-untranslated region of protein tyrosine phosphatase nonreceptor type 4 (PTPN4). However, w...

Background Dynamic prediction of patients’ mortality risk in ICU with time series data is limited due to the high dimensionality, uncertainty with sampling intervals, and other issues. New deep learning method, temporal convolution network (TCN), makes it possible to deal with complex clinical time series data in ICU. We aimed to develop and valida...

Background: Dynamic prediction of patients’ mortality risk in ICU with time series data is limited due to the high dimensionality, uncertainty with sampling intervals, and other issues. New deep learning method, temporal convolution network (TCN), makes it possible to deal with complex clinical time series data in ICU. We aimed to develop and valid...

Manganese superoxide dismutase (SOD2) is a key enzyme to scavenge free radical superoxide in the mitochondrion. SOD2 deficiency leads to oxidative injury in cells. Bupivacaine, a local anesthetic commonly used in clinic, could induce neurotoxic injury via oxidative stress. The role and the mechanism of SOD2 regulation in bupivacaine-induced oxidati...

The mortality rate of elderly patients with Coronavirus Disease 2019 (COVID-19) was significantly higher than the overall mortality rate. However, besides age, leading death risk factors for the high mortality in elderly patients remain unidentified. This retrospective study included 210 elderly COVID-19 patients (aged ≥ 65 years), of whom 175 pati...

Myocardial ischemia/reperfusion (I/R) injury leads to high mortality and morbidity due to the incomplete understanding of the underlying mechanism and the consequent lack of effective therapy. The present study revealed and validated key candidate genes in relation to inflammation and apoptosis pathways underlying myocardial I/R injury. Cathepsin S...

Coronavirus disease-2019 (COVID-19) has rapidly spread worldwide. High-flow nasal cannula therapy (HFNC) is a major oxygen supporting therapy for severely ill patients, but information regarding the timing of HFNC application is scarce, especially in elderly patients. We retrospectively analyzed the clinical data of 110 elderly patients (≥65 years)...

Forkhead box protein O1 (FOXO1), a nuclear transcription factor, is preferably activated in the myocardium of diabetic mice. However, its role and mechanism in the development of diabetic cardiomyopathy in non‐obese insulin‐deficient diabetes are unclear. We hypothesized that cardiac FOXO1 over‐activation was attributable to the imbalanced myocardi...

Background During the COVID-19 pandemic, not only was there a lack of personal protective equipment (PPE) for health care workers but a dearth in training in respect of its donning and doffing. This study compared two training methods for donning and doffing PPE in order to teach health care workers how to do so more effectively and quickly. Metho...

Cardiac dysfunction resulting from sepsis may cause significant morbidity and mortality, and ferroptosis plays a role in this pathology. Dexmedetomidine (Dex), a α2‑adrenergic receptor (α2‑AR) agonist exerts cardioprotective effects against septic heart dysfunction, but the exact mechanism is unknown. In the present study, sepsis was induced by cec...

Oxidative stress induced necroptosis is important in myocardial ischemia/reperfusion injury. Dexmedetomidine (Dex), an α2-adrenoceptor (α2-AR) agonist, has protective effect on oxidative stress induced cell apoptosis, but effects of Dex and Dex-mediated α2-AR activation on oxidant induced necroptosis was unclear. H9C2 cardiomyocytes were pre-treate...

Diabetic hearts are more susceptible to myocardial ischemia/reperfusion (I/R) injury and less sensitive to ischemic postconditioning (IPostC), but the underlying mechanisms remain unclear. PKCβ2 is preferentially overactivated in diabetic myocardium, in which autophagy status is abnormal. This study determined whether hyperglycemia-induced PKCβ2 ac...