New insights into the role of mitochondrial metabolic dysregulation and immune infiltration in septic cardiomyopathy by integrated bioinformatics analysis and experimental validation.

BACKGROUND: Septic cardiomyopathy (SCM), a common cardiovascular comorbidity of sepsis, has emerged among the leading causes of death in patients with sepsis. SCM's pathogenesis is strongly affected by mitochondrial metabolic dysregulation and immune infiltration disorder. However, the specific mechanisms and their intricate interactions in SCM remain unclear. This study employed bioinformatics analysis and drug discovery approaches to identify the regulatory molecules, distinct functions, and underlying interactions of mitochondrial metabolism and immune microenvironment, along with potential interventional strategies in SCM. METHODS: GSE79962, GSE171546, and GSE167363 datasets were obtained from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) and module genes were identified using Limma and Weighted Correlation Network Analysis (WGCNA), followed by functional enrichment analysis. Machine learning algorithms, including support vector machine-recursive feature elimination (SVM-RFE), least absolute shrinkage and selection operator (LASSO) regression, and random forest, were used to screen mitochondria-related hub genes for early diagnosis of SCM. Subsequently, a nomogram was developed based on six hub genes. The immunological landscape was evaluated by single-sample gene set enrichment analysis (ssGSEA). We also explored the expression pattern of hub genes and distribution of mitochondria/inflammation-related pathways in UMAP plots of single-cell dataset. Potential drugs were explored using the Drug Signatures Database (DSigDB). In vivo and in vitro experiments were performed to validate the pathogenetic mechanism of SCM and the therapeutic efficacy of candidate drugs. RESULTS: Six hub mitochondria-related DEGs [MitoDEGs; translocase of inner mitochondrial membrane domain-containing 1 (TIMMDC1), mitochondrial ribosomal protein S31 (MRPS31), F-box only protein 7 (FBXO7), phosphatidylglycerophosphate synthase 1 (PGS1), LYR motif containing 7 (LYRM7), and mitochondrial chaperone BCS1 (BCS1L)] were identified. The diagnostic nomogram model based on the six hub genes demonstrated high reliability and validity in both the training and validation sets. The immunological microenvironment differed between SCM and control groups. The Spearman correlation analysis revealed that hub MitoDEGs were significantly associated with the infiltration of immune cells. Upregulated hub genes showed remarkably high expression in the naive/memory B cell, CD14+ monocyte, and plasma cell subgroup, evidenced by the feature plot. The distribution of mitochondria/inflammation-related pathways varied across subgroups among control and SCM individuals. Metformin was predicted to be the most promising drug with the highest combined score. Its efficacy in restoring mitochondrial function and suppressing inflammatory responses has also been validated. CONCLUSIONS: This study presents a comprehensive mitochondrial metabolism and immune infiltration landscape in SCM, providing a potential novel direction for the pathogenesis and medical intervention of SCM.

Migraine-like headache in subjects with isolated Lambl's excrescences: a case series and literature review.

AIM: Lambl's excrescences are mobile, thin, fibrinous connective tissue strands typically found on left-sided cardiac values. Migraine is positively associated with structural cardiac anomalies. However, it remains unclear whether Lambl's excrescences are associated with migraine. METHODS: Retrospective review of 182 inpatients with Lambl's excrescences confirmed by transesophageal echocardiogram in Chinese PLA General Hospital since January 2010. Among them, those with isolated Lambl's excrescences presented with migraine-like headache were included. We collected information on the demographics and clinical profiles of all participants, and performed follow-up visits. RESULTS: A total of 8 patients presented with migraine-like headache among 15 patients with isolated Lambl's excrescences. They included 2 men and 6 women, with an average age of 44.63 ± 12.24 years. Among these patients, 3 had visual aura, and 6 manifested infarct-like lesions on magnetic resonance imaging, of which 2 developed lesions after first visit. During follow-up, 4 patients suffering from intervention for Lambl's excrescences dramatically reduced headache recurrence compared to the other 4 patients only receiving migraine preventive medications. CONCLUSIONS: This study supports the hypothesis that microemboli from isolated Lambl's excrescences could cause migraine-like headache. And intervention for Lambl's excrescences may be crucial for preventing headache recurrence.

This study supports the hypothesis that microemboli from isolated Lambl's excrescences could cause migraine-like headache.The small sample size study fails to make management recommendations.

Proteomics profiling reveals mitochondrial damage in the thalamus in a mouse model of chronic migraine.

BACKGROUND: Migraine, a complex brain disorder, is regarded as a possible clinical manifestation of brain energy dysfunction. The trigeminovascular system is considered the basis for the pathogenesis of migraine, hence we depicted the proteomics profiling of key regions in this system, then focusing on protein alterations related to mitochondrial function. The aim of this study is to illustrate the role of mitochondria in migraine. METHODS: A mouse model of chronic migraine (CM) was established by repeated nitroglycerin (NTG) stimulation and evaluated by von-Frey filaments, a hot plate and a light-dark box. Differentially expressed proteins (DEPs) in some subcortical brain regions of the trigeminovascular system were screened through liquid chromatography-tandem mass spectrometry (LC‒MS/MS) to analyse the specificity of key signaling pathways in different brain regions. And then mitochondrial function, structure and dynamics were determined by qPCR, ELISA, and transmission electron microscope (TEM). Finally, the effect of mitochondrial intervention-Urolithin A (UA) on CM was investigated. RESULTS: Repeated NTG injection triggered photophobia, periorbital and hind paw allodynia in mice. The proteomics profiling of CM model showed that 529, 109, 163, 152 and 419 DEPs were identified in the thalamus, hypothalamus, periaqueductal grey (PAG), trigeminal ganglion (TG) and trigeminocervical complex (TCC), respectively. The most significant changes in the brain region-specific pathways pointed to thalamic mitochondrial impairment. NTG induced mitochondrial structural disruption, dysfunction and homeostatic dysregulation, which could be partially attenuated by UA intervention. CONCLUSION: Our findings highlight the involvement of mitochondrial damage in the thalamus in central sensitization of CM, which provides evidence of possible metabolic mechanisms in migraine pathophysiology.

Molecular mechanisms of coronary microvascular endothelial dysfunction in diabetes mellitus: focus on mitochondrial quality surveillance.

Coronary microvascular endothelial dysfunction is both a culprit and a victim of diabetes, and can accelerate diabetes-related microvascular and macrovascular complications by promoting vasoconstrictive, pro-inflammatory and pro-thrombotic responses. Perturbed mitochondrial function induces oxidative stress, disrupts metabolism and activates apoptosis in endothelial cells, thus exacerbating the progression of coronary microvascular complications in diabetes. The mitochondrial quality surveillance (MQS) system responds to stress by altering mitochondrial metabolism, dynamics (fission and fusion), mitophagy and biogenesis. Dysfunctional mitochondria are prone to fission, which generates two distinct types of mitochondria: one with a normal and the other with a depolarized mitochondrial membrane potential. Mitochondrial fusion and mitophagy can restore the membrane potential and homeostasis of defective mitochondrial fragments. Mitophagy-induced decreases in the mitochondrial population can be reversed by mitochondrial biogenesis. MQS abnormalities induce pathological mitochondrial fission, delayed mitophagy, impaired metabolism and defective biogenesis, thus promoting the accumulation of unhealthy mitochondria and the activation of mitochondria-dependent apoptosis. In this review, we examine the effects of MQS on mitochondrial fitness and explore the association of MQS disorders with coronary microvascular endothelial dysfunction in diabetes. We also discuss the potential to treat diabetes-related coronary microvascular endothelial dysfunction using novel MQS-altering drugs.

Identification of proteomic markers for prediction of the response to 5-Fluorouracil based neoadjuvant chemoradiotherapy in locally advanced rectal cancer patients.

BACKGROUND: Neoadjuvant chemoradiotherapy (nCRT) prior to surgery is the standard treatment for patients with locally advanced rectal cancer (LARC), while parts of them show poor therapeutic response accompanied by therapy adverse effects. Predictive biomarkers for nCRT response could facilitate the guidance on treatment decisions but are still insufficient until now, which limits the clinical applications of nCRT in LARC patients. METHODS: In our study, 37 formalin-fixed paraffin-embedded tumor biopsies were obtained from patients with LARC before receiving 5-fluorouracil based nCRT. Proteomics analyses were conducted to identify the differentially expressed proteins (DEPs) between total responders (TR) and poor responders (PR). The DEPs were validated via ROC plotter web tool and their predictive performance was evaluated by receiver operating characteristic analysis. Functional enrichment analyses were performed to further explore the potential mechanisms underlying nCRT response. RESULTS: Among 3,998 total proteins, 91 DEPs between TR and PR were screened out. HSPA4, NIPSNAP1, and SPTB all with areas under the curve (AUC) ~ 0.8 in the internal discovery cohort were independently validated by the external mRNA datasets (AUC ~ 0.7), and their protein levels were linearly correlated with the graded responses to nCRT in the internal cohort. The combination of HSPA4 and SPTB could distinctly discriminate the TR and PR groups (AUC = 0.980, p < 0.0001). Moreover, multiple combinations of the three proteins realized increased specificity and/or sensitivity, while achieving favorable predictive value when moderate responders were introduced into the ROC analysis. Pathways including DNA damage repair, cell cycle, and epithelial mesenchymal transition were involved in nCRT response according to the enrichment analysis results. CONCLUSIONS: HSPA4, SPTB and NIPSNAP1 in tumor biopsies and/or their optional combinations might be potential predictive markers for nCRT response in patients with LARC. The DEPs and their related functions have implications for the potential mechanisms of treatment response to nCRT in patients with LARC.

ITIH4, as an inflammation biomarker, mainly increases in bacterial bloodstream infection.

Bloodstream infection (BSI) is usually accompanied with the changes of varieties of inflammation proteins. In our previous study, we identified that inter-α-trypsin inhibitor heavy chain H4 (ITIH4) was highly expressed in the infection arms than the normal control arm. However, the correlated verification and mechanism remain obscure. Escherichia coli infected mice model and clinical serum samples were used to validate the concentration of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10), as well as ITIH4, in ELISA method. Cytokines (IL-6, TNF-α, IL-10 and lipopolysaccharide (LPS)) were used to stimulate the HepG2 cell model to explore which cytokines influence the expression of ITIH4. JAK/STAT inhibitor was treated before IL-6 and LPS stimulation. Westernblot, as well as real-time PCR were performed to detect the expression of ITIH4 in liver tissue from protein and transcription levels. Immunohistochemistry analysis was used to observe the expression of ITIH4 in mice liver tissue. In mice model, IL-6, TNF-α, as well as IL-10 increased in the infection arms than the normal control arm. ITIH4 in serum and liver tissue of mice model increased from 1 h to 128 h, which were remarkably different from that of the normal control arm. Besides, ITIH4 increased in the bacterial infection arm greatly than the fungemia arm, mycoplasma pneumoniae (MP) arm and febrile arm in clinical serum samples. Furthermore, using the HepG2 cell line, we demonstrated that ITIH4 was up-regulated at both protein and mRNA levels upon dose- and time- response treatments with IL-6, as well as LPS. Moreover, IL-6 or LPS mediated induction of ITIH4 expression could be significantly decreased by treatment with an JAK/STAT inhibitor in protein or mRNA level. No changes were observed after TNF-α or IL-10 stimulation. ITIH4 might be a critical inflammatory biomarker which correlated with the development of BSI, especially with bacterial bloodstream infection. It is expected that this study would provide some insights into potential functional mechanisms underlying BSI.

Fibronectin and colorectal cancer: signaling pathways and clinical implications.

Colorectal cancer (CRC) is the fourth leading cause of cancer deaths worldwide, with poor prognosis mainly related to metastasis. Fibronectin (FN), a vital component of the extracellular matrix (ECM), has been found involved in tumorigenesis and malignant progression in different types of malignancy. Numerous studies have indicated the distinct expression of FN in various cancers and demonstrated the different functions of FN in the proliferation, migration, and invasion of cancers. Meanwhile, FN isoforms have been extensively used for targeted drug delivery and imaging for tumors. Although a growing number of studies on FN in CRC have been reported, integrated reviews on the relationship between FN and CRC are rare. In this review, we will summarize the association between FN and CRC, including the signaling pathways and molecules involved in, as well as potential diagnostic and therapeutic values of FN for patients with CRC.

Research and progress on biomarkers of neuromyelitis optica spectrum disorders.

Neuromyelitis optica spectrum disorders (NMOSD) are a demyelinating disorder of the central nervous system based on the involvement of the optic nerve and/or spinal cord. The disease is characterized by high recurrence and disability. NMOSD is mainly diagnosed by AQP4-IgG and MOG-IgG. However, there are still some patients with negative or undetermined double-antibody, and AQP4-IgG and MOG-IgG cannot indicate the clinical disease activity. Therefore, it is urgent to explore interesting biomarkers in serum and cerebrospinal fluid to promote early clinical diagnosis and/or as a target for diagnosis and treatment. This article summarized the research progress in serum and cerebrospinal fluid biomarkers of astrocytes, neurons, myelin sheath, and other damage after the onset of NMOSD. Besides the value of microglial activation-related proteins in the diagnosis and treatment of NMOSD was prospected, so as to promote the research progress of NMOSD.

Pum2-Mff axis fine-tunes mitochondrial quality control in acute ischemic kidney injury.

Mitochondrial fission factor (Mff) has been demonstrated to play a role in the activation of mitochondrial cleavage and mitochondrial death, denoting its role in the regulation of mitochondrial quality control. Recent evidence suggested that the mRNA translation of Mff is under the negative regulation by the RNA-binding protein Pumilio2 (Pum2). This study was designed to examine the role of Pum2 and Mff in the governance of mitochondrial quality control in a murine model of acute ischemic kidney injury. Our results indicated that genetic deletion of Mff overtly attenuated ischemic acute kidney injury (AKI)-induced renal failure through inhibition of pro-inflammatory response, tubular oxidative stress, and ultimately cell death in the kidney. Furthermore, Mff inhibition effectively preserved mitochondrial homeostasis through amelioration of mitochondrial mitosis, restoration of Sirt1/3 expression, and boost of mitochondrial respiration. Western blot analysis revealed that levels of Pum2 were significantly downregulated by ischemic AKI, inversely coinciding with levels of Mff. Overexpression of Pum2 reduced ischemic AKI-mediated Mff upregulation and offered protection on renal tubules through modulation of mitochondrial quality control. Taken together, our data have unveiled the molecular mechanism of the Pum2-Mff axis in mitochondrial quality control in a mouse model of ischemic AKI. These data indicated the therapeutic potential of Pum2 activation and Mff inhibition in the management of ischemic AKI.

Oxycodone protects cardiomyocytes from ischemia-reperfusion-induced apoptosis via PI3K/Akt pathway.

Ischemia/reperfusion (I/R) cause secondary myocardial damage following a blood reflow after myocardial infarction. This study aimed to explore oxycodone as a myocardial protector after an I/R injury in rats. Oxycodone reduced myocardial infarction volume, an I/R-induced apoptosis of the cardiomyocytes, the serum levels of CK-MB and LDH. The ejection fraction and fraction shortening in the I/R rats also increased. From the molecular mechanism, it was evident that oxycodone not only decreased the expression levels of Bax, active-caspase 3 protein but also increased the expression levels of Bcl2, p-PI3K, and p-Akt protein in heart tissue of the I/R rats. In vitro, oxycodone induced anti-H9c2 cell apoptosis after hypoxia/reoxygenation (H/R). However, its ability to act as a myocardial protector deteriorated in the presence of a PI3K/Akt pathway inhibitor.

Prevalence and risk factors associated with headache amongst medical staff in South China.

BACKGROUND: A previous study by our team reported the prevalence of primary headache disorders and factors associated with headache among nurses in three hospitals in North China. The aim of this cross-sectional survey was to learn more about how medical nurses in South China were affected by headache. Additionally, we determined the prevalence of headache and measured the impact of headache among doctors in mainland China for the first time. METHODS: Stratified random cluster sampling was used to select 280 physicians and 365 nurses from various departments in four hospitals in Sanya, which is one of southernmost cities in China. Information was collected on demographic data, occupational factors and headache characteristics by using a structured questionnaire. RESULTS: Among 645 medical staff, 548 (85%) responded (doctors = 240, nurses = 308). Among the medical staff, the 1-year prevalence of primary headache disorders was 50%, with 25.9% experiencing migraine and 24.1% experiencing tension-type headache (TTH). The prevalence of migraine in female doctors was higher than that in female nurses, although this difference was not significant (32.4% vs. 29.8%, P = 0.628). Multivariate analysis showed that being female and working in other specialties (Emergency Department & Radiology Department) remained independent risk factors for migraine in doctors (OR 2.314 and 3.223). In nurses, being married was a risk factor for migraine (OR 3.728), and job titles remained an independent risk factor for migraine and TTH (OR 2.294 and 4.695). Working more than 6 night-shifts per month was associated with an increased prevalence of migraine and TTH in doctors; the same was true in nurses for migraine, but not for TTH. CONCLUSION: The prevalence of primary headache disorders in both nurses and doctors is higher than that in the general population in South China. Our study shows that occupation, geography and sex may play an important role. Further, female doctors are more susceptible than female nurses to migraine. The risk factors relevant to headache that were found in this study should provide an important reference for promoting occupational health in medical staff, especially female doctors in China.

Noninvasive prenatal test for FGFR3-related skeletal dysplasia based on next-generation sequencing and plasma cell-free DNA: Test performance analysis and feasibility exploration.

OBJECTIVE: To explore the feasibility and accuracy of a noninvasive prenatal test for fibroblast growth factor receptor 3 (FGFR3)-related skeletal dysplasia based on next-generation sequencing (NGS) of plasma cell-free DNA. METHOD: Fragmented genome DNA (gDNA) of fetuses with achondroplasia (ACH) and thanatophoric dysplasia type I (TD I) was mixed with postdelivery maternal plasma cell-free DNA to generate spiked samples of different modeled fetal fractions. Multiplex polymerase chain reaction was used to amplify the 19 FGFR3 loci, and the amplification products were then sequenced by NGS to detect the fetal mutant alleles. Then, maternal plasma samples of pregnant women carrying ACH (n = 4) and TD I fetuses (n = 2), as well as healthy controls (n = 15), were tested by NGS, and the test performance was evaluated. RESULTS: Fetal FGFR3 mutations were detected in all artificial mixtures with fetal gDNA concentrations above 3%. In clinical validation, our method identified all fetal FGFR3 mutant alleles from maternal plasma, with no false positive results. The sensitivity and specificity of our method were 100% (95% CI, 54.1%-100%) and 100% (78.2%-100%), respectively. CONCLUSION: Our method had a favorable performance for noninvasively detecting fetal FGFR3 mutations in maternal plasma, highlighting its promising value in developing a noninvasive prenatal test for de novo and paternally inherited disorders.

[Analysis of the gene mutation in an inherited FVII deficiency patient].

OBJECTIVE: The identify the gene defect of an inherited FVII deficiency patient. METHODS: The promoter, all the exons and exon-intron boundaries and 3' UTR of F7 gene of the proband were analyzed by direct sequencing. The defected mutations were confirmed by sequencing the complementary strand. The mutations would be screened in the related database and 150 healthy donors to identify the SNP. By splice site prediction, we analyzed the pathogenesis of defected mutations. RESULTS: Genetic analysis revealed G to A transition at 15975 in the intron 6 of F7 gene (IVS6-1G>A) and A to G transition at 16813 in the intron 7 of F7 gene (IVS7+7 A>G). According to the fruitfly, the acceptor site could not be recognized when a G to A substitution took place. The closest candidate splice site was located 132 bp downstream. The distance was probably too far to allow the use of the cryptic splice site and resulted in the skipping of exon6. A to G transition at 16813 in the intron 7 of F7 gene could not change the splice site, but modify a different molecular interaction that is important for the splice process. CONCLUSION: The heterozygous mutation of IVS6-1G>A combined with polymorphism of IVS7+7 A>G in F7 gene relates to the FVII deficiency.

[Sensitivity and specificity of noninvasive prenatal fetal RhD genotesting: a meta-analysis].

OBJECTIVE: To explore the sensitivity, specificity and clinical validity of fetal Rh genotyping from maternal blood. METHODS: A comprehensive literature search of PubMed, Embase and Web of Science was performed for describing fetal RhD determination from maternal blood. The inclusion criteria were established based on the validity criteria for diagnostic research. And the eligible entries were collected and analyzed with MetaDisc4.0. RESULTS: This meta-analysis included 55 studies with a total of 17 138 samples. The random-effect model was used for analysis because of heterogeneity. The pooled sensitivity and specificity were 98.5% and 97.3% respectively. The SROC curve was plotted and the area under the curve (AUC) calculated (AUC = 0.994). The subgroup and sensitivity analyses were performed. The sensitivity of 25 studies with samples<100 (94.6%) was significantly lower than those of 19 studies with samples 100-300 (98.5%) and 11 studies with samples>300 (99.0%) (χ² = 36.800, 106.062, P < 0.05). The sensitivity of 19 studies with samples 100-300 (98.5%) was not different from that of 11 studies with samples >300 (99.0%)( χ² = 3.068, P > 0.05). CONCLUSIONS: Noninvasive prenatal diagnosis of fetal RhD status from maternal blood represents a significant achievement in the application of research with high sensitivity and specificity. It may be applied for screening testing of all RhD⁻ negative pregnant women.

Phosphoglycerate mutase 5 exacerbates alcoholic cardiomyopathy in male mice by inducing prohibitin-2 dephosphorylation and impairing mitochondrial quality control.

BACKGROUND: The induction of mitochondrial quality control (MQC) mechanisms is essential for the re-establishment of mitochondrial homeostasis and cellular bioenergetics during periods of stress. Although MQC activation has cardioprotective effects in various cardiovascular diseases, its precise role and regulatory mechanisms in alcoholic cardiomyopathy (ACM) remain incompletely understood. METHODS: We explored whether two mitochondria-related proteins, phosphoglycerate mutase 5 (Pgam5) and prohibitin 2 (Phb2), influence MQC in male mice during ACM. RESULTS: Myocardial Pgam5 expression was upregulated in a male mouse model of ACM. Notably, following ACM induction, heart dysfunction was markedly reversed in male cardiomyocyte-specific Pgam5 knockout (Pgam5cKO) mice. Meanwhile, in alcohol-treated male mouse-derived neonatal cardiomyocytes, Pgam5 depletion preserved cell survival and restored mitochondrial dynamics, mitophagy, mitochondrial biogenesis and the mitochondrial unfolded protein response (mtUPR). We further found that in alcohol-treated cardiomyocyte, Pgam5 binds Phb2 and induces its dephosphorylation at Ser91. Alternative transduction of phospho-mimetic (Phb2S91D) and phospho-defective (Phb2S9A) Phb2 mutants attenuated and enhanced, respectively, alcohol-related mitochondrial dysfunction in cardiomyocytes. Moreover, transgenic male mice expressing Phb2S91D were resistant to alcohol-induced heart dysfunction. CONCLUSIONS: We conclude that ACM-induced Pgam5 upregulation results in Pgam5-dependent Phb2S91 dephosphorylation, leading to MQC destabilisation and mitochondrial dysfunction in heart. Therefore, modulating the Pgam5/Phb2 interaction could potentially offer a novel therapeutic strategy for ACM in male mice. HIGHLIGHTS: Pgam5 knockout attenuates alcohol-induced cardiac histopathology and heart dysfunction in male mice. Pgam5 KO reduces alcohol-induced myocardial inflammation, lipid peroxidation and metabolic dysfunction in male mice. Pgam5 depletion protects mitochondrial function in alcohol-exposed male mouse cardiomyocytes. Pgam5 depletion normalises MQC in ACM. EtOH impairs MQC through inducing Phb2 dephosphorylation at Ser91. Pgam5 interacts with Phb2 and induces Phb2 dephosphorylation. Transgenic mice expressing a Ser91 phospho-mimetic Phb2 mutant are resistant to ACM.

A SERS nanocellulose-paper-based analytical device for ultrasensitive detection of Alzheimer's disease.

BACKGROUND: Alzheimer's disease (AD), one of the most prevalent neurodegenerative diseases, results in severe cognitive decline and irreversible memory loss. Early detection of AD is significant to patients for personalized intervention since effective cure and treatment methods for AD are still lacking. Despite the severity of the disease, existing highly sensitive AD detection methods, including neuroimaging and brain deposit-positive lesion tests, are not suitable for screening purposes due to their high cost and complicated operation. Therefore, these methods are unsuitable for early detection, especially in low-resource settings. Although regular paper-based microfluidics are cost-efficient for AD detection, they are restricted by a poor limit of detection (LOD). RESULTS: To address the above limitations, we report the ultrasensitive and low-cost nanocellulose paper (nanopaper)-based analytical microfluidic devices (NanoPADs) for detecting one of the promising AD blood biomarkers (glial fibrillary acidic protein, GFAP) using Surface-enhanced Raman scattering (SERS) immunoassay. Nanopaper offers advantages as a SERS substrate, such as an ultrasmooth surface, high optical transparency, and tunable chemical properties. We detected the target GFAP in artificial serum, achieving a LOD of 150 fg mL-1. SIGNIFICANCE: The developed NanoPADs are distinguished by their cost-efficiency and ease of implementation, presenting a promising avenue for effective early detection of AD's GFAP biomarker with ultrahigh sensitivity. More importantly, our work provides the experimental routes for SERS-based immunoassay of biomarkers on NanoPADs for various diseases in the future.

Erratum to "PGAM5-Mediated PHB2 Dephosphorylation Contributes to Diabetic Cardiomyopathy by Disrupting Mitochondrial Quality Surveillance".

[This corrects the article DOI: 10.34133/research.0001.].

DNA-PKcs Phosphorylates Cofilin2 to Induce Endothelial Dysfunction and Microcirculatory Disorder in Endotoxemic Cardiomyopathy.

The presence of endotoxemia is strongly linked to the development of endothelial dysfunction and disruption of myocardial microvascular reactivity. These factors play a crucial role in the progression of endotoxemic cardiomyopathy. Sepsis-related multiorgan damage involves the participation of the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs). However, whether DNA-PKcs contributes to endothelial dysfunction and myocardial microvascular dysfunction during endotoxemia remains unclear. Hence, we conducted experiments in mice subjected to lipopolysaccharide (LPS)-induced endotoxemic cardiomyopathy, as well as assays in primary mouse cardiac microvascular endothelial cells. Results showed that endothelial-cell-specific DNA-PKcs ablation markedly attenuated DNA damage, sustained microvessel perfusion, improved endothelial barrier function, inhibited capillary inflammation, restored endothelium-dependent vasodilation, and improved heart function under endotoxemic conditions. Furthermore, we show that upon LPS stress, DNA-PKcs recognizes a TQ motif in cofilin2 and consequently induces its phosphorylation at Thr25. Phosphorylated cofilin2 shows increased affinity for F-actin and promotes F-actin depolymerization, resulting into disruption of the endothelial barrier integrity, microvascular inflammation, and defective eNOS-dependent vasodilation. Accordingly, cofilin2-knockin mice expressing a phospho-defective (T25A) cofilin2 mutant protein showed improved endothelial integrity and myocardial microvascular function upon induction of endotoxemic cardiomyopathy. These findings highlight a novel mechanism whereby DNA-PKcs mediates cofilin2Thr25 phosphorylation and subsequent F-actin depolymerization to contribute to endotoxemia-related cardiac microvascular dysfunction.

The DNA-dependent protein kinase catalytic subunit exacerbates endotoxemia-induced myocardial microvascular injury by disrupting the MOTS-c/JNK pathway and inducing profilin-mediated lamellipodia degradation.

Rationale: The DNA-dependent protein kinase catalytic subunit (DNA-PKcs) promotes pathological mitochondrial fission during septic acute kidney injury. The mitochondrial open reading frame of the 12S rRNA type-c (MOTS-c) is a mitochondria-derived peptide that exhibits anti-inflammatory properties during cardiovascular illnesses. We explored whether endotoxemia-induced myocardial microvascular injury involved DNA-PKcs and MOTS-c dysregulation. Methods: To induce endotoxemia in vivo, endothelial cell-specific DNA-PKcs-knockout mice were injected intraperitoneally with a single dose of lipopolysaccharide (10 mg/kg) and evaluated after 72 h. Results: Lipopolysaccharide exposure increased DNA-PKcs activity in cardiac microvascular endothelial cells, while pharmacological inhibition or endothelial cell-specific genetic ablation of DNA-PKcs reduced lipopolysaccharide-induced myocardial microvascular dysfunction. Proteomic analyses showed that endothelial DNA-PKcs ablation primarily altered mitochondrial protein expression. Verification assays confirmed that DNA-PKcs drastically repressed MOTS-c transcription by inducing mtDNA breaks via pathological mitochondrial fission. Inhibiting MOTS-c neutralized the endothelial protective effects of DNA-PKcs ablation, whereas MOTS-c supplementation enhanced endothelial barrier function and myocardial microvascular homeostasis under lipopolysaccharide stress. In molecular studies, MOTS-c downregulation disinhibited c-Jun N-terminal kinase (JNK), allowing JNK to phosphorylate profilin-S173. Inhibiting JNK or transfecting cells with a profilin phosphorylation-defective mutant improved endothelial barrier function by preventing F-actin depolymerization and lamellipodial degradation following lipopolysaccharide treatment. Conclusions: DNA-PKcs inactivation during endotoxemia could be a worthwhile therapeutic strategy to restore MOTS-c expression, prevent JNK-induced profilin phosphorylation, improve F-actin polymerization, and enhance lamellipodial integrity, ultimately ameliorating endothelial barrier function and reducing myocardial microvascular injury.