Threshold of hyperglycaemia associated with mortality in critically ill patients: a multicentre, prospective, observational study using continuous glucose monitoring.

AIMS/HYPOTHESIS: Continuous glucose monitoring (CGM) provides comprehensive information on the exposure to dysglycaemia. This study aimed to investigate the threshold of hyperglycaemia related to mortality risk in critically ill patients using CGM technology. METHODS: A total of 293 adult critically ill patients admitted to intensive care units of five medical centres were prospectively included between May 2020 and November 2021. Participants wore intermittently scanned CGM for a median of 12.0 days. The relationships between different predefined time above ranges (TARs), with the thresholds of hyperglycaemia ranging from 7.8 to 13.9 mmol/l (140-250 mg/dl), and in-hospital mortality risk were assessed by multivariate Cox proportional regression analysis. Time in ranges (TIRs) of 3.9 mmol/l (70 mg/dl) to the predefined hyperglycaemic thresholds were also assessed. RESULTS: Overall, 66 (22.5%) in-hospital deaths were identified. Only TARs with a threshold of 10.5 mmol/l (190 mg/dl) or above were significantly associated with the risk of in-hospital mortality, after adjustment for covariates. Furthermore, as the thresholds for TAR increased from 10.5 mmol/l to 13.9 mmol/l (190 mg/dl to 250 mg/dl), the hazards of in-hospital mortality increased incrementally with every 10% increase in TARs. Similar results were observed concerning the associations between TIRs with various upper thresholds and in-hospital mortality risk. For per absolute 10% decrease in TIR 3.9-10.5 mmol/l (70-190 mg/dl), the risk of in-hospital mortality was increased by 12.1% (HR 1.121 [95% CI 1.003, 1.253]). CONCLUSIONS/INTERPRETATION: A glucose level exceeding 10.5 mmol/l (190 mg/dl) was significantly associated with higher risk of in-hospital mortality in critically ill patients.

Improving enteral nutrition tolerance and protein intake maybe beneficial to intensive care unit patients.

Enteral nutrition (EN) is important for critically ill patients. This study investigated the current situation of EN treatment in SHANGHAI intensive care units (ICUs). We hypothesized that improving EN practice in SHANGHAI may benefit the prognosis of ICU patients. Clinical information on EN use was collected using clinic information forms in 2019. The collected data included the patient's general clinical information, EN prescription status, EN tolerance status, and clinical outcomes. The observation time points were days 1, 3, and 7 after starting EN. A total of 491 patients were included. The proportion of EN intolerance (defined as < 20 kcal/kg/day) decreased, with rates of intolerance of 100%, 82.07%, 70.61%, and 52.23% at 1, 3, 7, and 14 days, respectively. Age, mNutric score, and protein intake < 0.5 g/kg/day on day 7 were risk factors for 28-day mortality.The EN tolerance on day 7 and protein intake > 0.5 g/kg/day on day 3 or day 7 might affect the 28-day mortality. Risk factors with EN tolerance on day 7 by logistic regression showed that the AGI grade on day 1 was a major factor against EN tolerance. The proportion of EN tolerance in SHANGHAI ICU patients was low. Achieving tolerance on day 7 after the start of EN is a protective factor for 28-day survival. Improving EN tolerance and protein intake maybe beneficial for ICU patients.

Bone Mesenchymal Stem Cells Origin Exosomes are Effective Against Sepsis-Induced Acute Kidney Injury in Rat Model.

Introduction: The incidence and mortality rates of sepsis-induced acute kidney injury (SAKI) remain high, posing a substantial healthcare burden. Studies have implicated a connection between the development of SAKI and inflammation response, apoptosis, and autophagy. Moreover, evidence suggests that manipulating autophagy could potentially influence the prognosis of this condition. Notably, exosomes derived from bone mesenchymal stem cells (BMSCs-Exo) have exhibited promise in mitigating cellular damage by modulating pathways associated with inflammation, apoptosis, and autophagy. Thus, this study aims to investigate the influence of BMSCs-Exo on SAKI and the potential mechanisms that drive this impact. Methods: The SAKI model was induced in HK-2 cells using lipopolysaccharide (LPS), while rats underwent cecal ligation and puncture (CLP) to simulate the condition. Cell viability was assessed using the CCK-8 kit, and kidney damage was evaluated through HE staining, blood urea nitrogen (BUN), and serum creatinine (SCr) measurements. Inflammatory-related RNAs and proteins were quantified via qPCR and ELISA, respectively. Apoptosis was determined through apoptosis-related protein levels, flow cytometry, and TUNEL staining. Western blot analysis was utilized to measure associated protein expressions. Results: In vivo, BMSCs-Exo ameliorated kidney injury in CLP-induced SAKI rats, reducing inflammatory cytokine production and apoptosis levels. Fluorescence microscope observed the absorption of BMSCs-Exo by renal cells following injection via tail vein. In the SAKI rat kidney tissue, there was an upregulation of LC3-II/LC3-I, p62, and phosphorylated AMP-activated protein kinase (p-AMPK) expressions, indicating blocked autophagic flux, while phosphorylated mammalian target of rapamycin (p-mTOR) expression was downregulated. However, BMSCs-Exo enhanced LC3-II/LC3-I and p-AMPK expression, concurrently reducing p62 and p-mTOR levels. In vitro, BMSCs-Exo enhanced cell viability in LPS-treated HK-2 cells, and exerted anti-inflammation and anti-apoptosis effects which were consistent with the results in vivo. Similarly, rapamycin (Rapa) exhibited a protective effect comparable to BMSCs-Exo, albeit partially abrogated by 3-methyladenine (3-MA). Conclusion: BMSCs-Exo mitigate inflammation and apoptosis through autophagy in SAKI, offering a promising avenue for SAKI treatment.

Intestinal epithelial pH-sensing receptor GPR65 maintains mucosal homeostasis via regulating antimicrobial defense and restrains gut inflammation in inflammatory bowel disease.

Intestinal epithelial cell (IEC) regulation of barrier function and mucosal homeostasis enables the establishment of a harmonious gut microenvironment. However, host-derived regulatory networks that modulate intestinal antimicrobial defenses have not been fully defined. Herein we generated mice with IEC-specific deletion of Gpr65 (Gpr65ΔIEC) and investigated the role of epithelial GPR65 using DSS- and C. rodentium-induced murine colitis models. RNA sequencing analysis was conducted on colonic IECs from Gpr65fl/fl and Gpr65ΔIEC mice, and colonoids and colonic epithelial cell lines were used to evaluate the pH-sensing effect of GPR65. The expression of GPR65 was determined in IECs from patients with inflammatory bowel disease (IBD) and DSS colitis mice by qRT-PCR, Western blot, and immunohistochemistry, respectively. We observed that the absence of GPR65 in IECs abrogated homeostatic antimicrobial programs, including the production of antimicrobial peptides (AMPs) and defense response-associated proteins. Gpr65ΔIEC mice displayed dysbiosis of the gut microbiota and were prone to DSS- and C. rodentium-induced colitis, as characterized by significantly disrupted epithelial antimicrobial responses, pathogen invasion, and increased inflammatory infiltrates in the inflamed colon. RNA sequencing analysis revealed that deletion of GPR65 in IECs provoked dramatic transcriptome changes with respect to the downregulation of immune and defense responses to bacteria. Forced AMP induction assays conducted in vivo or in ex vivo colonoids revealed that IEC-intrinsic GPR65 signaling drove antimicrobial defense. Mechanistically, GPR65 signaling promoted STAT3 phosphorylation to optimize mucosal defense responses. Epithelial cell line and colonoid assays further confirmed that epithelial GPR65 sensing pH synergized with IL-22 to facilitate antimicrobial responses. Finally, the expression of GPR65 was markedly decreased in the inflamed epithelia of IBD patients and DSS colitis mice. Our findings define an important role of epithelial GPR65 in regulating intestinal homeostasis and mucosal inflammation and point toward a potential therapeutic approach by targeting GPR65 in the treatment of IBD.

Fatal multisystem inflammatory syndrome in a 78-year-old adult after severe COVID-19 pneumonia during 2022 Omicron variant epidemic in Shanghai, China.

Multisystem inflammatory syndrome adult type (MIS-A) is a rare type of post-acute COVID-19 syndrome which more frequently occurred in younger population. Here we present a 78-year-old Chinese female, the oldest case reported, diagnosed with MIS-A who had severe SARS-CoV-2 infection. She was diagnosed with severe COVID-19 and experienced an unexpected sudden hemodynamic collapse in the recovery period within three weeks. Her platelet count was sharply dropped, accompanied with sustained cardiac, kidney and liver injury. She was diagnosed with MIS-A according to criteria established by Center of Disease Control and Prevention. Though her condition was improved under administrating with high dose of methylprednisolone and intravenous immunoglobulin, methylprednisolone was unable to withdraw till two weeks as her partial pressure of oxygen/fraction of inspiration oxygen ratio and platelet count dropped on the heels of decreasing dosage. Unfortunately, the patient's condition gradually deteriorated with the development of severe nosocomial pneumonia. We presented this rare case in order to emphasize that MIS-A could occur in the elderly and the management of this population might be more difficult as the condition of the elderly with SARS-CoV-2 infection and MIS-A might be more severe.

Super resolution imaging reconstruction reveals that gold standard methods may not correctly conclude neural/brain functional recovery.

The status of cerebral perfusion and its restoration level play a vital role in the prognosis and clinical decision making of many neurosurgical diseases. As such, gold standard methods including CT, MR and ICP monitoring, which can indicate and measure cerebral perfusion and restoration, have been widely adopted to evaluate whether or not a patient has recovered from neurofunctional disabilities. This robust combination of methods, however, is confronted with a growing number of contradictions in recent years due to its inability to measure the status of cerebral reperfusion in microvasculature level, even though this has been shown to determine neurofunctional restoration as well or even better. To this date, nevertheless, we have very limited imaging methods that could evaluate human cerebral microperfusion both safely and accurately under most neurosurgical conditions. We herein report a new method of acquiring a patient's cerebral microperfusion status noninvasively which could display the precise distribution of microvasculature in deep cerebral regions with a resolution of ∼30 µm, using everyday bed-side ultrasonography combined with a computerized super-resolution reconstruction algorithm. Using this imaging modality, we found that a patient's cerebral microperfusion might not be improved by some routine administrations even though the gold standard method had yielded the opposite conclusions. Our imaging modality retains the safe, portable feature of ordinary ultrasonography while possesses the extraordinary super-resolution nature, which enables an efficient, precise diagnosis of cerebral perfusion. Most importantly, the super resolution nature of this method may also facilitate early-stage evaluation of a patient's neurofunctional restoration level and avoid overoptimistic conclusions from conventional angiography or ICP monitoring.

HMGB1 mediates lipopolysaccharide-induced macrophage autophagy and pyroptosis.

Autophagy and pyroptosis of macrophages play important protective or detrimental roles in sepsis. However, the underlying mechanisms remain unclear. High mobility group box protein 1 (HMGB1) is associated with both pyroptosis and autophagy. lipopolysaccharide (LPS) is an important pathogenic factor involved in sepsis. Lentivirus-mediated HMGB1 shRNA was used to inhibit the expression of HMGB1. Macrophages were treated with acetylation inhibitor (AA) to suppress the translocation of HMGB1 from the nucleus to the cytosol. Autophagy and pyroptosis-related protein expressions were detected by Western blot. The levels of caspase-1 activity were detected and the rate of pyroptotic cells was detected by flow cytometry. LPS induced autophagy and pyroptosis of macrophages at different stages, and HMGB1 downregulation decreased LPS-induced autophagy and pyroptosis. Treatment with acetylation inhibitor (anacardic acid) significantly suppressed LPS-induced autophagy, an effect that was not reversed by exogenous HMGB1, suggesting that cytoplasmic HMGB1 mediates LPS-induced autophagy of macrophages. Anacardic acid or an anti-HMGB1 antibody inhibited LPS-induced pyroptosis of macrophages. HMGB1 alone induced pyroptosis of macrophages and this effect was inhibited by anti-HMGB1 antibody, suggesting that extracellular HMGB1 induces macrophage pyroptosis and mediates LPS-induced pyroptosis. In summary, HMGB1 plays different roles in mediating LPS-induced autophagy and triggering pyroptosis according to subcellular localization.

Knockdown of lncRNA-ASLNC12002 alleviates epithelial-mesenchymal transition of type II alveolar epithelial cells in sepsis-induced acute respiratory distress syndrome.

Patients with sepsis-induced acute respiratory distress syndrome (ARDS) have higher mortality and poor prognosis than pneumonia-induced ARDS. Pulmonary fibrosis is an irreversible accumulation of connective tissue in the interstitium of the lung and closely associated with the epithelial-mesenchymal transition (EMT) of type II alveolar epithelial cells (AECIIs). Therefore, it is undoubtedly worth studying whether the EMT of AECIIs in sepsis-induced ARDS patients is different from that in patients with pneumonia-induced ARDS in the regulatory mechanism. Here, we will report for the first time that an lncRNA-ASLNC12002 is highly expressed in AECIIs of patients with sepsis-induced pneumonia and promotes EMT in AECIIs. The research results showed that the expression of ASLNC12002 in AECIIs derived from patients with sepsis-induced ARDS is significantly higher than that in normal people and pneumonia-induced ARDS patients. Mechanism research showed that ASLNC12002 can cause the inactivation of the anti-EMT pathway NR2F2/miR128-3p/Snail1 by acting as the sponge of miR128-3p. Functional experiments showed that targeted silencing of ASLNC12002 could effectively inhibit EMT progression in AECIIs of patients with sepsis-induced pneumonia by restoring NR2F2/miR128-3p/Snail1 pathway. In a word, our study shows for the first time that the inactivation of NR2F2/miR128-3p/Snail1 pathway caused by the enhanced expression of ASLNC12002 is the direct reason why AECIIs in sepsis-induced ARDS patients are prone to get EMT progress. ASLNC12002 has the potential to become a biological target for the prevention and treatment of pulmonary fibrosis in patients with sepsis-induced ARDS. At the same time, the expectation that ASLNC12002 and its related products may be used as clinical markers for the evaluation of early pulmonary fibrosis in ARDS patients should not be ignored.

Clinical features of omicron SARS-CoV-2 variants infection associated with co-infection and ICU-acquired infection in ICU patients.

Background: Although the decreasing rate of hospital admission in the omicron wave has led countries to loosen control, still the patients requires ICU admission. It is common for viral respiratory infections to be co-infected with bacteria. However, the difference between co-infection and ICU-acquired infection on their clinical characteristics and outcomes during the Omicron wave was little reported. Methods: Clinical and microbiological data were collected from ICU patients with omicron infection between April 1st, 2022, and May 31th, 2022 and a comprehensive comparative study of the clinical characteristics and endpoint were conducted. Results: The Omicron SARS-CoV-2 variants-infected patients requiring intensive care had high rates of co-infection (42.55%). Additionally, the ICU COVID-19 patients with co-infection showed more severe clinical features compared to those with ICU-acquired infection. Furthermore, Multivariate Cox analysis demonstrated that co-infection (hazard ratio: 4.670, p = 0.018) was a significant risk factor for poor outcomes in ICU patients with COVID-19. Besides, Kaplan-Meier survival curve analysis revealed that COVID-19 patients with co-infection had a significantly shorter 28-Day survival time compared to those with ICU-acquired infection (p < 0.001). Finally, our investigation identified a significant association between the presence of Candida app. in the broncho-alveolar lavage and an elevated risk of mortality (OR: 13.80, p = 0.002) and invasive ventilation (OR: 5.63, p = 0.01). Conclusion: Co-infection is prevalent among patients requiring intensive care and is linked to unfavorable outcomes in the Omicron wave. Consequently, more attention may be needed for the empirical antibacterial treatment in ICU patients within the COVID-19 Omicron variant, especially anti-fungi.

The combination of lactate level, lactate clearance and APACHE II score better predicts short-term outcomes in critically Ill patients: a retrospective cohort study.

BACKGROUND: The mortality rate is high in critically ill patients due to the difficulty of diagnosis and treatment. Thus, it is very important to explore the predictive value of different indicators related to prognosis in critically ill patients. METHODS: This was a retrospective cohort study of patients in the intensive care unit (ICU) of the Sixth People's Hospital in Shanghai, China. A total of 1465 ICU patients had lactate values > 2.1 mmol/L at least once within 24 h of ICU admission, and arterial blood gas was monitored more than twice during the ICU stay. RESULTS: The predictive value of lactate clearance at 24 h was not high, and the sensitivity and specificity were lower. The predictive value of the lactate level at baseline and the APACHE II score was higher than that of lactate clearance at 24 h in critically ill patients. The predictive value of the lactate level at baseline combined with the APACHE II score was higher than that of the lactate level at baseline or the APACHE II score alone. In addition, the predictive value of lactate clearance at 24 h combined with the APACHE II score was also significantly higher than that of lactate clearance at 24 h or the APACHE II score alone. In particular, the area under the ROC curve reached 0.900, the predictive value was markedly higher than that of the ROC alone, and the sensitivity and specificity were better when these three indicators were combined. CONCLUSIONS: The combination of lactate level, lactate clearance and APACHE II score better predicts short-term outcomes in critically ill patients.

Accuracy of the intermittently scanned continuous glucose monitoring system in critically ill patients: a prospective, multicenter, observational study.

OBJECTIVE: Continuous glucose monitoring (CGM) has the potential to improve glucose control in the intensive care unit (ICU) setting. We sought to evaluate the accuracy of the intermittently scanned CGM (isCGM) system in critically ill patients. RESEARCH DESIGN AND METHODS: Adult patients were consecutively enrolled from three ICUs from August 2020 to January 2021. The performance of FreeStyle Libre Pro was evaluated against the venous blood glucose samples as a reference. Numerical accuracy was examined by the mean absolute relative difference (MARD), the Bland-Altman analysis, and the International Organization for Standardization criteria. Clinical accuracy was assessed by performing the Clarke and consensus error grid analysis. RESULTS: A total of 122 patients were included and 3416 matched glucose pairs were analyzed. The overall MARD was 18.0%, and the highest MARD (33.1%) was observed in the hypoglycemic range (<70 mg/dL). The Bland-Altman analysis revealed a mean bias of -11.7 mg/dL, with the 95% limits of agreement of -73.0 to 49.5 mg/dL. The percentages of isCGM glucose values within ±15%/15, ±20%/20, and ±30%/30 mg/dL were 49.8%, 64.7%, and 84.5%, respectively. The Clarke and consensus error grid analysis showed acceptable clinical accuracy with 98.5% and 98.8% of glucose values falling into zones A and B. CONCLUSIONS: Our study demonstrated suboptimal overall accuracy of isCGM for critically ill patients. Whether the adjunctive use of isCGM could improve glucose management and health outcomes in the critically ill needs further investigation. CLINICAL TRIAL REGISTRATION: ChiCTR2100042036, Chinese Clinical Trial Registry.

Increased variability of mean arterial pressure is associated with increased risk of short-term mortality in intensive care unit: A retrospective study.

Background: In intensive care unit (ICU), what thresholds of MAP variability are effective in distinguishing low- and high-risk patients for short-term mortality (in-hospital and 28-day) remains unclear. Methods: Fifteen thousand five hundred sixty adult subjects admitted to ICU at Beth Israel Deaconess Medical Center (Boston, USA) between 2001 and 2012 were included in this retrospective study from MIMIC-III database. MAP within the first 24 h after admission were collected. Quantiles of MAP variability from 10% to 90% with 10% increasement each were considered to divide study participants into two groups, either having coefficients of variation of MAP greater or less than the given threshold. The threshold of MAP variability was identified by maximizing the odds ratio associated with increased risk of short-term mortality (in-hospital and 28-day). Logistic regression and Cox regression models were further applied to evaluate the association between increased variability of MAP and short-term mortality (in-hospital and 28-day). Results: 90% quantile of MAP variability was determined as the threshold generating the largest odds ratio associated with the increased risk of short-term mortality. Increased MAP variability, especially over 90% of MAP variability, was associated with increased risk of in-hospital mortality (odds ratio: 2.351, 95% CI: 2.064-2.673), and 28-day mortality (hazard ratio: 2.064, 95% CI: 1.820-2.337). Conclusion: Increased MAP variability, especially over 90% of MAP variability, is associated with short-term mortality. Our proposed threshold of MAP variability may aid in the early identification of critically ill patients with a high risk of mortality.

Unique Associations of DNA Methylation Regions With 24-Hour Blood Pressure Phenotypes in Black Participants.

BACKGROUND: Epigenetic marks (eg, DNA methylation) may capture the effect of gene-environment interactions. DNA methylation is involved in blood pressure (BP) regulation and hypertension development; however, no studies have evaluated its relationship with 24-hour BP phenotypes (daytime, nighttime, and 24-hour average BPs). METHODS: We examined the association of whole blood DNA methylation with 24-hour BP phenotypes and clinic BPs in a discovery cohort of 281 Blacks participants using reduced representation bisulfite sequencing. We developed a deep and region-specific methylation sequencing method, Bisulfite ULtrapLEx Targeted Sequencing and utilized it to validate our findings in a separate validation cohort (n=117). RESULTS: Analysis of 38 215 DNA methylation regions (MRs), derived from 1 549 368 CpG sites across the genome, identified up to 72 regions that were significantly associated with 24-hour BP phenotypes. No MR was significantly associated with clinic BP. Two to 3 MRs were significantly associated with various 24-hour BP phenotypes after adjustment for age, sex, and body mass index. Together, these MRs explained up to 16.5% of the variance of 24-hour average BP, while age, sex, and BMI explained up to 11.0% of the variance. Analysis of one of the MRs in an independent cohort using Bisulfite ULtrapLEx Targeted Sequencing confirmed its association with 24-hour average BP phenotype. CONCLUSIONS: We identified several MRs that explain a substantial portion of variances in 24-hour BP phenotypes, which might be excellent markers of cumulative effect of factors influencing 24-hour BP levels. The Bisulfite ULtrapLEx Targeted Sequencing workflow has potential to be suitable for clinical testing and population screenings on a large scale.

ZFP36 protects lungs from intestinal I/R-induced injury and fibrosis through the CREBBP/p53/p21/Bax pathway.

Acute lung injury induced by ischemia-reperfusion (I/R)-associated pulmonary inflammation is associated with high rates of morbidity. Despite advances in the clinical management of lung disease, molecular therapeutic options for I/R-associated lung injury are limited. Zinc finger protein 36 (ZFP36) is an AU-rich element-binding protein that is known to suppress the inflammatory response. A ZFP36 binding site occurs in the 3' UTR of the cAMP-response element-binding protein (CREB) binding protein (CREBBP) gene, which is known to interact with apoptotic proteins to promote apoptosis. In this study, we investigate the involvement of ZFP36 and CREBBP on I/R-induced lung injury in vivo and in vitro. Intestinal ischemia/reperfusion (I/R) activates inflammatory responses, resulting in injury to different organs including the lung. Lung tissues from ZFP36-knockdown mice and mouse lung epithelial (MLE)-2 cells were subjected to either Intestinal I/R or hypoxia/reperfusion, respectively, and then analyzed by Western blotting, immunohistochemistry, and real-time PCR. Silico analyses, pull down and RIP assays were used to analyze the relationship between ZFP36 and CREBBP. ZFP36 deficiency upregulated CREBBP, enhanced I/R-induced lung injury, apoptosis, and inflammation, and increased I/R-induced lung fibrosis. In silico analyses indicated that ZFP36 was a strong negative regulator of CREBBP mRNA stability. Results of pull down and RIP assays confirmed that ZFP36 direct interacted with CREBBP mRNA. Our results indicated that ZFP36 can mediate the level of inflammation-associated lung damage following I/R via interactions with the CREBBP/p53/p21/Bax pathway. The downregulation of ZFP36 increased the level of fibrosis.

ZFP36L2 regulates myocardial ischemia/reperfusion injury and attenuates mitochondrial fusion and fission by LncRNA PVT1.

Among several leading cardiovascular disorders, ischemia-reperfusion (I/R) injury causes severe manifestations including acute heart failure and systemic dysfunction. Recently, there has been increasing evidence suggesting that alterations in mitochondrial morphology and dysfunction also play an important role in the prognosis of cardiac disorders. Long non-coding RNAs (lncRNAs) form major regulatory networks altering gene transcription and translation. While the role of lncRNAs has been extensively studied in cancer and tumor biology, their implications on mitochondrial morphology and functions remain to be elucidated. In this study, the functional roles of Zinc finger protein 36-like 2 (ZFP36L2) and lncRNA PVT1 were determined in cardiomyocytes under hypoxia/reoxygenation (H/R) injury in vitro and myocardial I/R injury in vivo. Western blot and qRT-PCR analysis were used to assess the levels of ZFP36L2, mitochondrial fission and fusion markers in the myocardial tissues and cardiomyocytes. Cardiac function was determined by immunohistochemistry, H&E staining, and echocardiogram. Ultrastructural analysis of mitochondrial fission was performed using transmission electron microscopy. The mechanistic model consisting of PVT1 with ZFP36L2 and microRNA miR-21-5p with E3 ubiquitin ligase MARCH5 was assessed by subcellular fraction, RNA pull down, FISH, and luciferase reporter assays. These results identified a novel regulatory axis involving PVT1, miR-21-5p, and MARCH5 that alters mitochondrial morphology and function during myocardial I/R injury. Using an in vivo I/R injury mouse model and in vitro cardiomyocytes H/R model, we demonstrated that ZFP36L2 directly associates with PVT1 and alters mitochondrial fission and fusion. PVT1 also interactes with miR-21-5p and suppresses its expression and activity. Furthermore, we identified MARCH5 as a modifier of miR-21-5p, and its effect on mitochondrial fission and fusion are directly proportional to PVT1 expression during H/R injury. Our findings show that manipulation of PVT1-miR-21-5p-MARCH5-mediated mitochondrial fission and fusion via ZFP36L2 may be a novel therapeutic approach to regulate myocardial I/R injury.

Dietary Sodium Restriction Results in Tissue-Specific Changes in DNA Methylation in Humans.

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