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Calcium (Ca2+)/calmodulin-dependent protein kinase II (CaMKII) is activated during exercise by reactive oxygen species (ROS) and Ca2+ transients initiating muscle contraction. CaMKII modulates antioxidant, inflammatory, metabolic and autophagy signalling pathways. CaMKII is coded by four homologous genes (α, β, γ, and δ). In rat skeletal muscle, δ D, δ A , γ D , γ B and β M have been described while different characterisations of human skeletal muscle CaMKII isoforms have been documented. Precisely discerning between the various isoforms is pivotal for understanding their distinctive functions and regulatory mechanisms in response to exercise and other stimuli. This study aimed to optimize the detection of the different CaMKII isoforms by western blotting using eight different CaMKII commercial antibodies in human skeletal muscle. Exercise-induced posttranslational modifications, i.e. phosphorylation and oxidations, allowed the identification of specific bands by multitargeting them with different antibodies after stripping and reprobing. The methodology proposed has confirmed the molecular weight of β M CaMKII and allows distinguishing between γ/δ and δ D CaMKII isoforms. The corresponding molecular weight for the CaMKII isoforms resolved were: δ D , at 54.2 ± 2.1 kDa; γ/δ, at 59.0 ± 1.2 kDa and 61.6 ± 1.3 kDa; and β M isoform, at 76.0 ± 1.8 kDa. Some tested antibodies showed high specificity for the δ D , the most responsive isoform to ROS and intracellular Ca2+ transients in human skeletal muscle, while others, despite the commercial claims, failed to show such specificity. [Display omitted] • CaMKII, an enzyme coded by four genes (α, β, γ, δ), is activated by ROS and Ca2+ transients during exercise. • Using eight commercial antibodies, we describe a protocol to resolve CaMKII isoforms in human skeletal muscle by Western blot. • The observed molecular weights of CaMKII isoforms were β M : 76±1.8, γ/δ: 59±1.2/61.6±1.3, and δ D : 54.2±2.1 kDa, respectively. • Commercial antibodies with high specificity for the δ D CaMKII isoform have been identified. • We show how exercise-induced posttranslational modifications can be used to validate CaMKII antibody specificity. [ABSTRACT FROM AUTHOR]

Objective: Autoinflammation and phospholipase C (PLC) γ2–associated antibody deficiency and immune dysregulation (APLAID) syndrome is an autoinflammatory disease caused by gain‐of‐function variants in PLCG2. This study investigates the pathogenic mechanism of a novel variant of PLCG2 in a patient with APLAID syndrome. Methods: Whole‐exome sequencing and Sanger sequencing were used to identify the pathogenic variant in the patient. Single‐cell RNA sequencing, immunoblotting, luciferase assay, inositol monophosphate enzyme‐linked immunosorbent assay, calcium flux assay, quantitative PCR, and immunoprecipitation were used to define inflammatory signatures and evaluate the effects of the PLCG2 variant on protein functionality and immune signaling. Results: We identified a novel de novo variant, PLCG2 p.D993Y, in a patient with colitis, pansinusitis, skin rash, edema, recurrent respiratory infections, B‐cell deficiencies, and hypogammaglobulinemia. The single‐cell transcriptome revealed exacerbated inflammatory responses in the patient's peripheral blood mononuclear cells. Expression of the D993Y variant in HEK293T, COS‐7, and PLCG2 knock‐out THP‐1 cell lines showed heightened PLCγ2 phosphorylation; elevated inositol‐1,4,5‐trisphosphate production and intracellular Ca2+ release; and activation of the MAPK, NF‐κB, and NFAT signaling pathways compared with control‐transfected cells. In vitro experiments indicated that the D993Y variant altered amino acid properties, disrupting the interaction between the catalytic and autoinhibitory domains of PLCγ2, resulting in PLCγ2 autoactivation. Conclusion: Our findings demonstrated that the PLCG2 D993Y variant is a gain‐of‐function mutation via impairing its autoinhibition, activating multiple inflammatory signaling pathways, thus leading to APLAID syndrome. This study further broadens the molecular underpinnings and phenotypic spectrum of PLCγ2‐related disorders. [ABSTRACT FROM AUTHOR]

ABSTRACT Post‐inflammatory hyperpigmentation (PIH) is a very common disorder of cutaneous hyperpigmentation, which poses a persistent management challenge in the fields of dermatology and esthetics. This study was designed to explore the anti‐melanogenic and anti‐inflammatory effects of Bay 11‐7082, an NF‐κB inhibitor, using small‐molecule screening, to determine its potential application for PIH prevention. The molecular mechanisms were investigated in vitro and ex vivo in epidermis‐humanized mice using melanin content, RT‐PCR, and immunoblotting. Bay 11‐7082 suppressed proinflammatory cytokines and ameliorated 2,4‐dinitrofluorobenzene (DNFB)‐induced contact dermatitis on day 15. The suppression of melanin synthesis by Bay 11‐7082 was attributed to the reduction of MITF, which was induced by extracellular signal‐regulated kinase activation. Bay 11‐7082 reduced epidermal melanin accumulation in UVB‐stimulated ex vivo human epidermis as well as in the ear and tail skin of K14‐stem cell factor (SCF) transgenic mice. Topical administration of Bay 11‐7082 improved PIH on day 35 in the post‐DNFB dorsal skin of K14‐SCF transgenic mice. In conclusion, Bay 11‐7082 can be considered a promising candidate for the development of a preventive topical agent for PIH. [ABSTRACT FROM AUTHOR]

Introduction: Early-onset Alzheimer's disease (EOAD) is sporadic, highly heterogeneous, and its underlying pathogenic mechanisms remain largely elusive. Proteomics research aims to uncover the biological processes and key proteins involved in disease progression. However, no proteomic studies to date have specifically focused on EOAD brain tissue. Method: We integrated proteomic data from brain tissues of two Alzheimer's disease (AD) cohorts and constructed a protein co-expression network using weighted gene co-expression network analysis (WGCNA). We identified modules associated with EOAD, conducted functional enrichment analysis to understand the biological processes involved in EOAD, and pinpointed potential key proteins within the core modules most closely linked to AD pathology. Results: In this study, we identified a total of 2,749 proteins associated with EOAD. Through protein co-expression network analysis, we discovered 41 distinct co-expression modules. Notably, the proteins within the core module most closely linked to AD pathology were significantly enriched in neutrophil degranulation. Additionally, we identified two potential key proteins within this core module that have not been previously reported in AD and validated their expression levels in 5xFAD mice. Conclusion: In summary, through a protein co-expression network analysis, we identified EOAD-related biological processes and molecular pathways, and screened and validated two key proteins, ERBB2IP and LSP1. These proteins may play an important role in the progression of EOAD, suggesting they could serve as potential therapeutic targets for the disease. [ABSTRACT FROM AUTHOR]

Simple Summary: Treatments for colorectal cancer (CRC) largely rely on chemotherapeutics. For CRC treatment, irinotecan is widely used in various combinations with other drugs. Despite being an effective drug, irinotecan treatment often leads to drug resistance and tumor relapse. Mechanistically, it inhibits topoisomerase I and induces double-strand DNA breaks, which result in p53-dependent apoptosis. In the current study, we explored irinotecan-mediated, p53-independent pro- and anti-apoptotic effects. Our data show that irinotecan induces cyclin-dependent kinase inhibitors as well as anti-apoptotic proteins [osteopontin (OPN), survivin, and ISG15], the immunomodulatory molecule PD-L1, immune modulation mediated by proliferative NF-κB signaling, and metastatic markers (CD44, Sox2, Oct4, Snail, and Slug). Inhibition of OPN and/or NF-κB signaling potentiates irinotecan efficacy. The combination of OPN and/or an NF-κB inhibitor with irinotecan may lead to increased efficacy with reduced drug resistance. Among the most popular chemotherapeutic agents, irinotecan, regarded as a prodrug belonging to the camptothecin family that inhibits topoisomerase I, is widely used to treat metastatic colorectal cancer (CRC). Although immunotherapy is promising for several cancer types, only microsatellite-instable (~7%) and not microsatellite-stable CRCs are responsive to it. Therefore, it is important to investigate the mechanism of irinotecan function to identify cellular proteins and/or pathways that could be targeted for combination therapy. Here, we have determined the effect of irinotecan treatment on the expression/activation of tumor suppressor genes (including p15Ink4b, p21Cip1, p27Kip1, and p53) and oncogenes (including OPN, IL8, PD-L1, NF-κB, ISG15, Cyclin D1, and c-Myc) using qRT-PCR, Western blotting, immunofluorescence (IF), and RNA sequencing of tumor specimens. We employed stable knockdown, neutralizing antibodies (Abs), and inhibitors of OPN, p53, and NF-κB to establish downstream signaling and sensitivity/resistance to the cytotoxic activities of irinotecan. Suppression of secretory OPN and NF-κB sensitized colon cancer cells to irinotecan. p53 inhibition or knockdown was not sufficient to block or potentiate SN38-regulated signaling, suggesting p53-independent effects. Irinotecan treatment inhibited tumor growth in syngeneic mice. Analyses of allograft tumors from irinotecan-treated mice validated the cell culture results. RNA-seq data suggested that irinotecan-mediated activation of NF-κB signaling modulated immune and inflammatory genes in mice, which may compromise drug efficacy and promote resistance. In sum, these results suggest that, for CRCs, targeting OPN, NF-κB, PD-L1, and/or ISG15 signaling may provide a potential strategy to overcome resistance to irinotecan-based chemotherapy. [ABSTRACT FROM AUTHOR]

AbstractCaralluma europaea Guss. (C. europaea) is a medicinal plant used for cancer treatment. However, these treatments may be associated with complications that need to be investigated. This work aims to evaluate not only the chemical composition but also the hepatoprotective and anticancer properties of C. europaea extracts. The chemical constitution of the hydroethanolic extract was explored using gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). The hydroethanolic extract, flavonoids, and polyphenols-rich extract at 100, 15, and 50 mg/kg, respectively, were administered to acetaminophen-treated rats for seven days. We used Western blotting and Real-Time quantitative Polymerase Chain Reaction (RT-qPCR) to determine the protein and the mRNA levels of cancer stemness markers in pancreatic cancer cell lines MIA PaCa-2 and BxPC-3 exposed to increasing doses of C. europaea extracts. In silico analysis was used to evaluate the effects of phenolic compounds revealed in C. europaea on caspase-3 and HSP90, and on liver damage on CYP2E1. The primary phenolics detected by GC-MS and HPLC were ferulic acid and benzofurazan. The positive control group showed an increase in AST, ALT, ALP, triglycerides, and VLDL levels. C. europaea extracts demonstrated hepatoprotective effects by ameliorating acetaminophen-induced alterations of biochemical and hispathological parameters. Immunoblotting and RT-qPCR profiling of cancer stemness markers indicated a reduction in the expression levels of Oct-4 and Nanog proteins, as well as a reduction in the mRNA levels of CD133 by 50–60% and Sox2 by 80–90% in pancreatic cancer cells. Molecular docking showed that naringenin presented the highest docking Gscore on CYP2E1 (−8.199) and HSP90 (−7.742). In conclusion, C. europaea extracts could be considered as a safe and promising therapeutic strategy to sensitize pancreatic cancer cells to chemotherapy. [ABSTRACT FROM AUTHOR]

Background: Advances in diagnostic procedures have led to an increasing rate of diagnosis of autoimmune encephalitis or paraneoplastic neurological syndrome (AE/PNS) among patients with progressive supranuclear palsy (PSP)-like manifestations. Methods: In this narrative review, we first discuss the clinical characteristics of AE/PNS in comparison to those of PSP, followed by a discussion of diagnosis and treatment. Results: The antibodies involved in these conditions include anti-IgLON5, -Ma2, and -Ri antibodies, each of which has a characteristic clinical presentation. The steps in the diagnosis of AE/PNS in patients with PSP-like manifestations include (i) suspicion of AE/PNS based on clinical presentations atypical of PSP and (ii) antibody detection measures. Methods used to identify antibodies include a combination of tissue-based assays and confirmatory tests. The primary confirmatory tests include cell-based assays and immunoblotting. Treatments can be divided into immunotherapy and tumor therapies, the former of which includes acute and maintenance therapies. Conclusions: One of the major challenges of diagnosis is that existing reports on PSP-like patients with AE/PNS include only case reports, with the majority discussing antibodies other than anti-IgLON5 antibody. As such, more patients need to be evaluated to establish the relationship between antibodies and PSP-like manifestations. [ABSTRACT FROM AUTHOR]

Renal transporters (cotransporters, channels, and claudins) mediate homeostasis of fluids and electrolytes and are targets of hormonal and therapeutic regulators. Assessing renal transporter abundance with antibody probes by immunoblotting is an essential tool for mechanistic studies. Although journals require authors to demonstrate antibody specificity, there are no consensus guidelines for kidney sample preparation leading to lab-to-lab variability in immunoblot results. In this study, we determined the impact of sample preparation, specifically freeze-thawed (Frozen) versus freshly processed (Fresh) kidneys (female and male rats and mice) on immunoblot signal detection of 15 renal transporters and the impact of protease inhibitors during homogenization. In female Sprague-Dawley rat kidneys homogenized with aprotinin, Na2EDTA, PMSF, and phosphatase inhibitors, immunodetection signals were ∼50% lower in Frozen versus Fresh samples for most transporters. Inclusion of additional inhibitors (Roche cOmplete Protease Inhibitor, "+") only partially increased transporter immunoblot signals to near Fresh levels. In male Sprague-Dawley rats, immunoblot signal density was lower in Frozen+ versus Fresh+ despite additional inhibitors. In C57BL/6 male mice, immunoblot signals from proximal tubule transporters were lower in Frozen versus Fresh by ∼25–50% and greater in Frozen+. In contrast, immunodetection signal was equivalent in female Frozen+ versus female Fresh+ for claudin 2, villin, AQP1, NKCC2, NCC, ENaCβ, ENaCɣ, claudin 7, AQP2, NKAα1, and NKAβ1. Thus, kidney sample preparation variables, including freeze-thaw and protease inhibition, have substantial transporter-specific effects on quantification of renal transporter abundance by immunoblot. These findings underscore the critical importance of assessing and reporting the impact of sample preparation protocols on transporter recovery to ensure robust rigor and reproducibility. NEW & NOTEWORTHY: Freeze-thawing kidneys before homogenization is widely accepted in renal research. This study demonstrates that if kidneys are freeze-thawed just once before homogenization, immunoblot signals are reduced in a transporter-specific manner in rats and mice dependent on sex and that immunoblot signals can be partially recovered by adding additional protease inhibitors. These findings underscore the critical importance of assessing the impact of sample preparation, including freeze-thaw versus fresh, to ensure robust rigor and reproducibility. [ABSTRACT FROM AUTHOR]

Objectives To identify and characterize undescribed systemic sclerosis (SSc)-specific autoantibodies targeting nucleolar antigens and to assess their clinical significance. Methods We conducted proteome-wide autoantibody screening (PWAS) against serum samples from SSc patients with nucleolar patterned anti-nuclear antibodies (NUC-ANAs) of specific antibodies (Abs) unknown, utilizing wet protein arrays fabricated from in vitro human proteome. Controls included SSc patients with already-known SSc-specific autoantibodies, patients with other connective tissue diseases and healthy subjects. The selection of nucleolar antigens was performed by database search in the Human Protein Atlas. The presence of autoantibodies was certified by immunoblots and immunoprecipitations. Indirect immunofluorescence assays on HEp-2 cells were also conducted. Clinical assessment was conducted by retrospective review of electronic medical records. Results PWAS identified three candidate autoantibodies, including anti-nuclear valosin-containing protein-like (NVL) Ab. Additional measurements in disease controls revealed that only anti-NVL Abs are exclusively detected in SSc. Detection of anti-NVL Abs was reproduced by conventional assays such as immunoblotting and immunoprecipitation. Indirect immunofluorescence assays demonstrated homogeneous nucleolar patterns. Anti-NVL Ab-positive cases were characterized by significantly low prevalence of diffuse skin sclerosis and interstitial lung disease, compared with SSc cases with NUC-ANAs other than anti-NVL Abs, such as anti-U3-RNP and anti-Th/To Abs. Conclusion Anti-NVL Ab is an SSc-specific autoantibody associated with a unique combination of clinical features, including limited skin sclerosis and lack of lung involvement. [ABSTRACT FROM AUTHOR]

We examined how resistance exercise (RE), cycling exercise and disuse atrophy affect myosin heavy chain (MyHC) protein fragmentation. The 1boutRE study involved younger men (n = 8; 5 ± 2 years of RE experience) performing a lower body RE bout with vastus lateralis (VL) biopsies being obtained prior to and acutely following exercise. With the 10weekRT study, VL biopsies were obtained in 36 younger adults before and 24 h after their first/naïve RE bout. Participants also engaged in 10 weeks of resistance training and donated VL biopsies before and 24 h after their last RE bout. VL biopsies were also examined in an acute cycling study (n = 7) and a study involving 2 weeks of leg immobilization (n = 20). In the 1boutRE study, fragmentation of all MyHC isoforms (MyHCTotal) increased 3 h post‐RE (∼200%, P = 0.018) and returned to pre‐exercise levels by 6 h post‐RE. Interestingly, a greater magnitude increase in MyHC type IIa versus I isoform fragmentation occurred 3 h post‐RE (8.6 ± 6.3‐fold vs. 2.1 ± 0.7‐fold, P = 0.018). In 10weekRT participants, the first/naïve and last RE bouts increased MyHCTotal fragmentation 24 h post‐RE (+65% and +36%, P < 0.001); however, the last RE bout response was attenuated compared to the first bout (P = 0.045). Although cycling exercise did not alter MyHCTotal fragmentation, ∼8% VL atrophy with 2 weeks of leg immobilization increased MyHCTotal fragmentation (∼108%, P < 0.001). Mechanistic C2C12 myotube experiments indicated that MyHCTotal fragmentation is likely due to calpain proteases. In summary, RE and disuse atrophy increase MyHC protein fragmentation. Research into how ageing and disease‐associated muscle atrophy affect these outcomes is needed. Highlights: What is the central question of this study?How different exercise stressors and disuse affect skeletal muscle myosin heavy chain fragmentation.What is the main finding and its importance?This investigation is the first to demonstrate that resistance exercise and disuse atrophy lead to skeletal muscle myosin heavy chain protein fragmentation in humans. Mechanistic in vitro experiments provide additional evidence that MyHC fragmentation occurs through calpain proteases. [ABSTRACT FROM AUTHOR]

Background: We examined the physicochemical properties of IgD-type M protein from 10 patients with IgD-type M protein and those with other types of M protein. Methods: Identification of the L-chain type by routine methods (Immunoelectrophoresis: IEP, Immunofixation electrophoresis; IFE), detection of IgD-IgG complexes and the changes in the mobility by treatment with acid. Results: Identification of the L-chain type by both IEP and IFE was impossible. Only one patient revealed the possibility of IgD-IgG complex bands in 6 of the 10 samples. Changes in mobility by treatment with acid were observed in 8 of the 10 samples of IgD-type M protein. Conclusions: These abnormalities are caused by the primary structure of IgD, which may be related to the wellknown weak reactivity with L-chain antibody. [ABSTRACT FROM AUTHOR]

Aseptic necrosis of the femoral head is a staged process in which osteodestruction is replaced by the bone repair. The outcome of this disease may be characterized by severe discongruence of the hip joint area, disability of the patient. Recently, the research interest is drawn to molecular and cellular mechanisms of bone homeostasis disorders and ways of its correction. A number of studies have demonstrated the role of nonspecific inflammation in pathogenesis of aseptic necrosis. However, a more detailed study of dynamic changes in the activity of osteogenesis signaling pathways is required. The aim of this study was to assess the role of molecular patterns of inflammation and osteogenesis during aseptic necrosis of femoral head in experimental model. Surgical induction of aseptic necrosis of the femoral head was performed in 16 rats, which were removed biweekly from experiment (by 4 animals), for 8 weeks. The expression of genes encoding proteins involved in osteogenesis regulation was studied by qPCR with reverse transcription. Concentration of VCAM1, MMP9 proteins was assessed by immunoblotting. The results of our study demonstrated heterogenous dynamics of changes in molecular and cellular disorders associated with bone homeostasis regulation in pathogenesis of aseptic necrosis. For the first two weeks after surgical procedure, the expression of HIF1α and TNFα genes, as well as the concentration of MMP9 and VCAM1 proteins, were determined as predictor factors. After 1 month, VCAM1 protein concentration and TNFα gene expression acted as protector factors, whereas IL6 gene and MMP9 protein were considered predictive factors. After 6 weeks, the development of aseptic necrosis was promoted by expression of the IL4 gene, and after 8 weeks, by IL6 gene. Thus, an important role in regulation of osteoresorption belongs to nonspecific inflammation, which can be triggered by acute tissue hypoxia. A significant effect of the inflammation process persists up to 8 weeks after induction of avascular necrosis of femoral head. Pathogenesis of bone destruction is associated not only with an increased activity of osteoclastogenesis, but also with a decreased intensity of osteoblastogenesis. In general, the molecular and cellular pattern of bone homeostasis disorders varies depending on the stage of aseptic necrosis.

Abstract We examined how resistance exercise (RE), cycling exercise and disuse atrophy affect myosin heavy chain (MyHC) protein fragmentation. The 1boutRE study involved younger men (n = 8; 5 ± 2 years of RE experience) performing a lower body RE bout with vastus lateralis (VL) biopsies being obtained prior to and acutely following exercise. With the 10weekRT study, VL biopsies were obtained in 36 younger adults before and 24 h after their first/naïve RE bout. Participants also engaged in 10 weeks of resistance training and donated VL biopsies before and 24 h after their last RE bout. VL biopsies were also examined in an acute cycling study (n = 7) and a study involving 2 weeks of leg immobilization (n = 20). In the 1boutRE study, fragmentation of all MyHC isoforms (MyHCTotal) increased 3 h post‐RE (∼200%, P = 0.018) and returned to pre‐exercise levels by 6 h post‐RE. Interestingly, a greater magnitude increase in MyHC type IIa versus I isoform fragmentation occurred 3 h post‐RE (8.6 ± 6.3‐fold vs. 2.1 ± 0.7‐fold, P = 0.018). In 10weekRT participants, the first/naïve and last RE bouts increased MyHCTotal fragmentation 24 h post‐RE (+65% and +36%, P

Shiga toxin-producing Escherichia coli (STEC) causes acute intestinal infections and also causes acute renal failure, especially in children. Shiga toxins (Stx) occupy a central place in the pathogenesis of hemolytic uremic syndrome (HUS) in Escherichiosis. The presented work analyzes the effectiveness of laboratory diagnostics of enterohemorrhagic escherichiosis in patients at the stage of manifestation of HUS and/or acute renal failure using microbiological, immunological research methods and PCR analysis. The study used clinical material from 30 patients in the pediatric intensive care unit of the St. Vladimir Children’s City Clinical Hospital in Moscow with symptoms of HUS aged from 8 months to 5 years. Blood sera from 20 healthy donors were used as control. As a result of PCR analysis, stx2 DNA was detected in 23.3% of cases. Bacteriological research made it possible to sow a pure culture of Escherichia coli O157:H7 in only 3.3% of cases. Since the development of HUS begins in patients with acute intestinal infection caused by Shiga toxin-producing microorganisms starting from the 5th day of the disease, when antibiotic therapy is already carried out, the bacteria can be completely destroyed, which makes it difficult to identify them by bacteriological methods, as well as to detect genes encoding Shiga toxin in PCR analysis. Typically, patients with HUS are admitted to the intensive care unit 5–7 days after the onset of the disease, when class G immunoglobulins specific to the pathogen are already beginning to circulate in the blood. In this regard, the use of immunological tests can be effective to confirm the diagnosis of STEC infection. In our studies, enzyme immunoassay allowed us to detect antibodies to Stx2A in 63.3% and to Stx2B in 43.3% of patients. Using immunoblotting, antibodies to Stx2A were detected in all sera obtained from patients and in 66.7% of cases to Stx2B. Immunoblot analysis was characterized by higher sensitivity for detecting antibodies to Stx2, however, due to the presence of an immunological layer among healthy people, it is preferable to use ELISA analysis. In healthy donors with antibodies to Stx2, the antibody titer was significantly lower than in patients. Laboratory confirmation of the diagnosis of STEC infection is difficult when conducting microbiological and molecular genetic studies, which is confirmed in this work. The effectiveness of laboratory diagnostics can be expanded by performing an ELISA aimed at detecting antibodies to Stx2A.

Abstract Objective Extracellular vesicles (EVs) have been shown to play a critical role in promoting tumorigenesis. As EV research grows, it is of importance to have standardization of isolation, quality control, characterization and validation methods across studies along with reliable references to explore troubleshooting solutions. Therefore, our objective with this Research Note was to isolate EVs from multiple breast cancer cell lines and to describe and perform protocols for validation as outlined by the list of minimal information for studies of EVs (MISEV) from the International Society for Extracellular Vesicles. Results To isolate EVs, two techniques were employed: ultracentrifugation and size exclusion chromatography. Ultracentrifugation yielded better recovery of EVs in our hands and was therefore used for further validation. In order to satisfy the MISEV requirements, protein quantification, immunoblotting of positive (CD9, CD63, TSG101) and negative (TGFβ1, β-tubulin) markers, nanoflow cytometry and electron microscopy was performed. With these experiments, we demonstrate that yield of validated EVs varied between different breast cancer cell lines. Protocols were optimized to accommodate for low levels of EVs, and various technical and troubleshooting suggestions are included for potential application to other cell types that may provide benefit to investigators interested in future EV studies.

The reliable, accurate and quantitative targeted detection of proteins is a key technology in molecular and cell biology and molecular diagnostics. The current golden standard for targeted protein detection in complex mixtures such as complete cell lysates or body fluids is immunoblotting, a technology that was developed in the late 1970s and has not undergone major changes since. Although widespread, this methodology suffers from several disadvantages, such as the inability to detect low-abundant proteins or specific posttranslational modifications, the requirement for highly specific antibodies, the lack of quantitative power and the often-tedious practical procedures. Mass spectrometry (MS) based targeted protein detection is an alternative technology that could circumvent these caveats. Here, we compare immunoblotting with targeted protein mass spectrometry using a parallel reaction monitoring (PRM) regime on the Orbitrap mass spectrometer. We show that PRM based MS has superior sensitivity and quantitative accuracy over immunoblotting. The limit of detection for proteolytic peptides of a purified target protein was found to be in the mid- to low-attomole range and approximately one order of magnitude higher when embedded in a complex biological matrix. The incorporation of synthetic heavy isotope labeled (AQUA) peptides as internal calibrants into the PRM workflow allows for even higher accuracy for both the relative and absolute quantitation of tryptic target peptides. In conclusion, PRM is a versatile and sensitive technology, which can overcome the shortcomings of immunoblotting. We argue that PRM based MS could become the method of choice for the targeted detection of proteins in complex cellular matrices or body fluids and may eventually replace standard methods such as Western blotting and ELISA in biomedical research and in the clinic. [ABSTRACT FROM AUTHOR]

Simple Summary: Non-small cell lung cancer (NSCLC) accounts for 80–85% of primary lung cancers. Radiation therapy is widely used to treat both primary NSCLC and lung cancer that has spread to the brain. However, radiotherapy responses are not durable and toxicity limits therapy. Therefore, there is an urgent need for new agents that can enhance the effectiveness of radiation therapy in lung cancer and reduce its toxicity. We find that AM-101, a benzodiazepine analog, enhances the effects of radiation and significantly improves the survival of mice with lung cancer brain-metastatic tumors. Additionally, AM-101 makes radiation treatment work better and slows down the growth of NSCLC subcutaneous xenograft tumors in mice. AM-101 activates the GABA(A) receptor in lung cancer cells, triggering selective autophagy by causing GABARAP to form multimers and stabilizing the mitochondrial receptor Nix. GABA(A) receptor activation may improve tumor control and allow for lower radiation doses, reducing toxicity. In non-small cell lung cancer (NSCLC) treatment, radiotherapy responses are not durable and toxicity limits therapy. We find that AM-101, a synthetic benzodiazepine activator of GABA(A) receptor, impairs the viability and clonogenicity of both primary and brain-metastatic NSCLC cells. Employing a human-relevant ex vivo 'chip', AM-101 is as efficacious as docetaxel, a chemotherapeutic used with radiotherapy for advanced-stage NSCLC. In vivo, AM-101 potentiates radiation, including conferring a significant survival benefit to mice bearing NSCLC intracranial tumors generated using a patient-derived metastatic line. GABA(A) receptor activation stimulates a selective-autophagic response via the multimerization of GABA(A) receptor-associated protein, GABARAP, the stabilization of mitochondrial receptor Nix, and the utilization of ubiquitin-binding protein p62. A high-affinity peptide disrupting Nix binding to GABARAP inhibits AM-101 cytotoxicity. This supports a model of GABA(A) receptor activation driving a GABARAP–Nix multimerization axis that triggers autophagy. In patients receiving radiotherapy, GABA(A) receptor activation may improve tumor control while allowing radiation dose de-intensification to reduce toxicity. [ABSTRACT FROM AUTHOR]

BACKGROUND: A broad suite of bisphenol S (BPS) derivatives as alternatives for BPS have been identified in various human biological samples, including 4-hydroxyphenyl 4-isopropoxyphenylsulfone (BPSIP) detected in human umbilical cord plasma and breast milk. However, very little is known about the health outcomes of prenatal BPS derivative exposure to offspring. OBJECTIVES: Our study aimed to investigate the response of hepatic cholesterol metabolism by sex in offspring of dams exposed to BPSIP. METHODS: Pregnant ICR mice were exposed to 5μg/kg body weight (BW)/day of BPSIP, BPS, or E2 through drinking water from gestational day one until the pups were weaned. The concentration of BPSIP, BPS, or E2 in the plasma and liver of pups was determined by liquid chromatography-tandem mass spectrometry. Metabolic phenotypes were recorded, and histopathology was examined for liver impairment. Transcriptome analysis was employed to characterize the distribution and expression patterns of differentially expressed genes across sexes. The metabolic regulation was validated by quantitative real-time PCR, immunohistochemistry, and immunoblotting. The role of estrogen receptors (ERs) in mediating sex-dependent effects was investigated using animal models and liver organoids. RESULTS: Pups of dams exposed to BPSIP showed a higher serum cholesterol level, and liver cholesterol levels were higher in females and lower in males than in the controls. BPSIP concentration in the male liver was 1.22±0.25 ng/g and 0.69±0.27 ng/g in the female liver. Histopathology analysis showed steatosis and lipid deposition in both male and female offspring. Transcriptome and gene expression analyses identified sex-specific differences in cholesterol biosynthesis, absorption, disposal, and efflux between pups of dams exposed to BPSIP and those in controls. In vivo, chromatin immunoprecipitation analysis revealed that the binding of ERα protein to key genes such as Hmgcr, Pcsk9, and Abcg5 was attenuated in BPSIP-exposed females compared to controls, while it was enhanced in males. In vitro, the liver organoid experiments demonstrated that restoration of differential expression induced by BPSIP in key genes, such as Hmgcr, Ldlr, and Cyp7a1, to levels comparable to the controls was only achieved when treated with a combination of ERα agonist and ERβ; agonist. DISCUSSION: Findings from this study suggest that perinatal exposure to BPSIP disrupted cholesterol metabolism in a sex-specific manner in a mouse model, in which ERa played a crucial role both in vivo and in vitro. Therefore, it is crucial to systematically evaluate BPS derivatives to protect maternal health during pregnancy and prevent the transmission of metabolic disorders across generations [ABSTRACT FROM AUTHOR]

The youcai mosaic virus (YoMV) can infect a diverse array of crop species, such as Raphanus sativus, Brassica napus, Solanum nigrum, and Rehmannia glutinosa, causing substantial economic damage. This study aimed to develop a rapid, sensitive, and economical diagnostic method for YoMV. We successfully expressed and purified the recombinant His-CPYoMV-YZ protein in E. coli BL21, which was used to immunize New Zealand White rabbits, generating high-titer polyclonal antibodies (PAb-CPYoMV-YZ). Additionally, a serological-based reverse transcription loop-mediated isothermal amplification (S-RT-LAMP) assay was refined, combining serological and molecular detection techniques to enhance practicality. Utilizing PAb-CPYoMV-YZ, we developed four techniques for detecting YoMV: Western blot, dot immunoblotting assay, enzyme-linked immunosorbent assay (ELISA), and S-RT-LAMP. YoMV isolates from various regions and hosts were analyzed. The results indicated that PAb-CPYoMV-YZ was highly effective in detecting YoMV across a range of hosts and isolates from diverse regions. This study fills an important gap in the serological detection of YoMV and provides a practical tool for on-site diagnosis and control of YoMV infection. [ABSTRACT FROM AUTHOR]

Cervical malignancy (CC) is the 2nd most prevalent malignancy among females, leading to cancer mortality. Primary detection of CC tumors results in an improved prognosis. CC is a malignant gynecological tumor, with few treatment options. New diagnostic and therapeutic agents are required to expand patient survival and quality of life. If CC tumors can be found at an early stage, the prognosis is much brighter. New diagnostic and therapeutic agents are needed to increase patient survival and quality of life. In this work, we performed whole-exome sequencing utilizing V5 (Illumina platform) 10 samples, 5 control and 5 CC tumour tissue, and we compared the results with transcriptome studies. KMT2C variations were shown to be among the most vicious in this analysis. From an Indian viewpoint, we found a plethora of SNVs and mutations, including those with known, unknown, and possible effects on health. Based on our findings, we know that the KMT2C gene is on chr. Seven and in exon 8, all three recognized variants are missense, synonymous, coding synonymous, non-coding variants, and GnomAD MAF (− 0.05). The variation at position (7:152265091, T > A, SNV 62478356) in KMT2C is unique, potent, and pathogenic. The missense coding transcript CIQTNF maps to chromosome 7 and displays T > C SNV. In addition, we performed single strand conformational polymorphism analysis on 64 samples and further confirmed them using Sanger sequencing to understand and verify the mutations. KMT2C shows a log FC value of − 1.16. Understanding emerging harmful mutations from an Indian viewpoint is facilitated by our bioinformatics-based, extensive correlation studies of WES analysis. Potentially harmful and new mutations were found in our preliminary analysis; among these ten top mutated genes, KMT2C and CIQTNF were altered in ten cases of CC with an Indian phenotype. [ABSTRACT FROM AUTHOR]

GelBox is open-source software that was developed with the goal of enhancing rigor, reproducibility, and transparency when analyzing gels and immunoblots. It combines image adjustments (cropping, rotation, brightness, and contrast), background correction, and band-fitting in a single application. Users can also associate each lane in an image with metadata (for example, sample type). GelBox data files integrate the raw data, supplied metadata, image adjustments, and band-level analyses in a single file to improve traceability. GelBox has a user-friendly interface and was developed using MATLAB. The software, installation instructions, and tutorials, are available at https://campbell-muscle-lab.github.io/GelBox/. NEW & NOTEWORTHY: GelBox is open-source software that was developed to enhance rigor, reproducibility, and transparency when analyzing gels and immunoblots. It combines image adjustments (cropping, rotation, brightness, and contrast), background correction, and band-fitting in a single application. Users can also associate each lane in an image with metadata (for example, sample type). [ABSTRACT FROM AUTHOR]

Objective: This study aimed to investigate the effect of plasma‐activated Ringer's lactate solution (PAL) on oral squamous cell carcinoma (OSCC) cells and carcinogenic processes with a particular focus on iron and collagenous matrix formation. Materials and Methods: We used three OSCC cell lines, one keratinocyte cell line, and two fibroblast lines, and cell viability assays, immunoblotting, flow cytometry, and transmission electron microscopy were performed to evaluate the effect and type of cell death. The effect of PAL treatment on lysyl oxidase (LOX) expression was investigated in vitro and in vivo. Tamoxifen‐inducible Mob1a/b double‐knockout mice were used for the in vivo experiment. Results: PAL killed OSCC cells more effectively than the control nontumorous cells and suppressed cell migration and invasion. Ferroptosis occurred and the protein level of LOX was downregulated in cancer cells in vitro and in vivo. Additionally, PAL improved the survival rate of mice and suppressed collagenous matrix formation. Conclusions: We demonstrated that PAL specifically kills OSCC cells and that ferroptosis occurs in vitro and in vivo. Furthermore, PAL can prevent carcinogenesis and improve the survival rate of oral cancer, especially tongue cancer, by changing collagenous matrix formation via LOX suppression. [ABSTRACT FROM AUTHOR]

Background: Here, we evaluated whether the histone lysine demethylase 5B (JARID1B), is involved in osteogenic phenotype commitment of periodontal ligament cells (PDLCs), by considering their heterogeneity for osteoblast differentiation. Materials and Methods: Epigenetic, transcriptional, and protein levels of a gene set, involved in the osteogenesis, were investigated by performing genome‐wide DNA (hydroxy)methylation, mRNA expression, and western blotting analysis at basal (without osteogenic induction), and at the 3rd and 10th days of osteogenic stimulus, in vitro, using PDLCs with low (l) and high (h) osteogenic potential as biological models. Results: h‐PDLCs showed reduced levels of JARID1B, compared to l‐PDLCs, with significant inversely proportional correlations between RUNX2 and RUNX2/p57. Epigenetically, a significant reduction in the global H3K4me3 content was observed only in h‐PDLCs. Immunoblotting data reveal a significant reduction in the global H3K4me3 content, at 3 days of induction only in h‐PDLCs, while an increase in the global H3K4me3 content was observed at 10 days for both PDLCs. Additionally, positive correlations were found between global H3K4me3 levels and JARID1B gene expression. Conclusions: Altogether, our results show the crucial role of JARID1B in repressing PDLCs osteogenic phenotype and this claims to pre‐clinical protocols proposing JARID1B as a potential therapeutic target. [ABSTRACT FROM AUTHOR]

Background Objectives Methods Results Conclusions Anti‐p200 pemphigoid is a rare autoimmune subepidermal blistering disease. Although the phenomenon of epitope spreading has been reported to be common in anti‐p200 pemphigoid, the association between its clinical and immunoserological features has yet to be elucidated.Our aim was to compare the clinical and immunoserological characteristics of anti‐p200 pemphigoid patients with and without epitope spreading.We performed a retrospective cohort study encompassing 30 patients with anti‐p200 pemphigoid between January 2015 and December 2022. The clinical and immunoserological characteristics of anti‐p200 pemphigoid were analyzed using combined immunoserological assays.Epitope spreading was observed in 11 of 30 patients (36.7%) with anti‐p200 pemphigoid. Compared with patients in the non‐epitope spreading group, patients in the epitope spreading group showed more heterogeneous clinical presentations (P = 0.018), a higher proportion of mucosal involvement (P = 0.003), higher Bullous Pemphigoid Disease Area Index (BPDAI) scores for skin erosions/blisters (P = 0.018), mucosal erosions/blisters (P = 0.001), activity (P = 0.017) and total scores (P = 0.022), and required a higher initial dose of prednisone for disease control (P = 0.040).This study supported the idea that anti‐p200 pemphigoid was prone to epitope spreading. Anti‐p200 pemphigoid patients with epitope spreading are more likely to present heterogeneous clinical phenotypes, frequent mucosal involvement, and a more severe and recalcitrant disease course. [ABSTRACT FROM AUTHOR]

The cGAS-STING pathway is a pivotal element of the innate immune system, recognizing cytosolic DNA to initiate the production of type I interferons and pro-inflammatory cytokines. This study investigates the alterations of the cGASSTING signaling components in the cortex and hippocampus of mice aged 24 and 108 weeks. In the cortex of old mice, an increase in the dsDNA sensor protein cGAS and its product 2030-cGAMP was observed, without corresponding activation of downstream signaling, suggesting an uncoupling of cGAS activity from STING activation. This phenomenon may be attributed to increased dsDNA concentrations in the EC neurons, potentially arising from nuclear DNA damage. Contrastingly, the hippocampus did not exhibit increased cGAS activity with aging, but there was a notable elevation in STING levels, particularly in microglia, neurons and astrocytes. This increase in STING did not correlate with enhanced IRF3 activation, indicating that brain inflammation induced by the cGAS-STING pathway may manifest extremely late in the aging process. Furthermore, we highlight the role of autophagy and its interplay with the cGAS-STING pathway, with evidence of autophagy dysfunction in aged hippocampal neurons leading to STING accumulation. These findings underscore the complexity of the cGASSTING pathway's involvement in brain aging, with regional variations in activity and potential implications for neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

To investigate the effects of Cirsilineol on cell viability, pyroptosis, and inflammation in hypoxia/reoxygenation-induced renal tubular cells, we utilized the renal tubular epithelial cell line HK2. The in vitro renal injury model was induced by hypoxia/reoxygenation. Cell viability in hypoxia/reoxygenation-induced HK2 cells was determined using a methylthiazolyldiphenyltetrazolium bromide assay and lactate dehydrogenase releasing kit. The effects of Cirsilineol on inflammation and pyroptosis in HK2 cells were evaluated using enzyme-linked immunosorbent assay, flow cytometry, and immunoblot assays. Our results demonstrated that Cirsilineol promoted survival in hypoxia/reoxygenation-induced tubular cells, inhibited inflammation, and reduced pyroptosis in these cells. Further investigation revealed that the protective effects of Cirsilineol are mediated by the suppression of the Toll-like receptor 4/nuclear factor kappa B pathway, which mitigates the cellular response to hypoxia/ reoxygenation injury. Our study suggests that Cirsilineol protects renal tubular epithelial cells from hypoxia/reoxygenation injury by inhibiting inflammation and pyroptosis, highlighting its potential therapeutic value in renal conditions characterized by ischemic injury. [ABSTRACT FROM AUTHOR]

Cervical cancer (CC) is a common gynecological malignancy, and improving cisplatin sensitivity has become a hot topic in CC chemotherapy research. Polyphyllin I (PPI), a potent bioactive compound found in Rhizoma Paridis, known for its anticancer properties, remains underexplored in CC resistance. In this study, we evaluated PPI's impact on cisplatin-resistant CC cells and elucidated its underlying mechanism. Our findings reveal that PPI enhances the sensitivity of cisplatin-resistant CC cells to the drug, promotes apoptosis, and inhibits cell migration. Mechanistically, PPI was found to regulate p53 expression and its target genes, and suppressing p53 expression reverses PPI's sensitizing effect in drug-resistant CC cells. In conclusion, PPI showed promise in sensitizing cisplatin-resistant human CC cells to cisplatin treatment, suggesting that it could serve as a potent adjunct therapy for cervical cancer, particularly for cases that have developed resistance to cisplatin, thereby providing a promising basis for further clinical investigation into PPI for enhancing the efficacy of existing chemotherapy regimens in resistant cervical cancer. [ABSTRACT FROM AUTHOR]

The gut microbiome plays an essential role in host immune responses, including allergic reactions. However, commensal gut microbiota is extremely sensitive to antibiotics and excessive usage can cause microbial dysbiosis. Herein, we investigated how changes in the gut microbiome induced by ampicillin affected the production of IgG1 and IgG2a antibodies in mice subsequently exposed to Anisakis pegreffii antigens. Ampicillin treatment caused a notable change in the gut microbiome as shown by changes in both alpha and beta diversity indexes. In a 1-dimensional immunoblot using Anisakis-specific anti-mouse IgG1, a 56-kDa band corresponding to an unnamed Anisakis protein was detected using mass spectrometry analysis only in ampicillin-treated mice. In the Anisakis-specific anti-mouse IgG2a-probed immunoblot, a 70-kDa band corresponding to heat shock protein 70 (HSP70) was only detected in ampicillin-treated and Anisakis-immunized mice. A 2-dimensional immunoblot against Anisakis extract with immunized mouse sera demonstrated altered spot patterns in both groups. Our results showed that ampicillin treatment altered the gut microbiome composition in mice, changing the immunization response to antigens from A. pegreffii. This research could serve as a basis for developing vaccines or allergy immunotherapies against parasitic infections. [ABSTRACT FROM AUTHOR]

Altered serum Netrin-1 levels have been widely reported in cancer and other clinical diseases and they are often measured by commercial ELISA kits. However, we found the questionable results using these kits and therefore performed this simple study to evaluate their accuracy in detection of serum Netrin-1. Four commonly used commercial kits were collected. The kit standards were serially diluted or spiked into serum samples. The cells with confirmed expression of Netrin-1 and their culture medium, as well as the Netrin-1 controls of each kit were used for the kits to detect. The cell lysate samples and the kit controls were also blotted on a nitrocellulose membrane for detection antibodies of each kit to probe. Detection of the Netrin-1 standards in serum by each kit were all affected. Only one kit was able to detect Netrin-1 in the cell lysate or medium. No ELISA kits could detect all Netrin-1 controls of the four kits. None of the detection antibodies correctly probed Netrin-1 in the dot blot. The accuracy of these four Netrin-1 ELISA kits is under question. Reported serum Netrin-1 levels based on measurements by these kits need be carefully interpreted. [ABSTRACT FROM AUTHOR]

Highlights: SPI1 and SMAD5 are upregulated during MC3T3-E1 cell osteogenic differentiation. SPI1 enhances SMAD5 transcription. Icariin increases SMAD5 expression by upregulating SPI1. The SPI1/SMAD5 axis underlies the promoting effect of icariin on MC3T3-E1 cell osteogenic differentiation. Background: Dysregulation of osteogenic differentiation is a crucial event during osteoporosis. The bioactive phytochemical icariin has become an anti-osteoporosis candidate. Here, we elucidated the mechanisms underlying the promoting function of icariin in osteogenic differentiation. Methods: Murine pre-osteoblast MC3T3-E1 cells were stimulated with dexamethasone (DEX) to induce osteogenic differentiation, which was evaluated by an Alizarin Red staining assay and ALP activity measurement. The mRNA amounts of SPI1 and SMAD5 were detected by real-time quantitative PCR. Expression analysis of proteins, including osteogenic markers (OPN, OCN and RUNX2) and autophagy-associated proteins (LC3, Beclin-1, and ATG5), was performed by immunoblotting. The binding of SPI1 and the SMAD5 promoter was predicted by the Jaspar2024 algorithm and confirmed by chromatin immunoprecipitation (ChIP) experiments. The regulation of SPI1 in SMAD5 was examined by luciferase assays. Results: During osteogenic differentiation of MC3T3-E1 cells, SPI1 and SMAD5 were upregulated. Functionally, SPI1 overexpression enhanced autophagy and osteogenic differentiation of MC3T3-E1 cells, while SMAD5 downregulation exhibited opposite effects. Mechanistically, SPI1 could enhance SMAD5 transcription and expression. Downregulation of SMAD5 also reversed SPI1 overexpression-induced autophagy and osteogenic differentiation in MC3T3-E1 cells. In MC3T3-E1 cells under DEX stimulation, icariin increased SMAD5 expression by upregulating SPI1. Furthermore, icariin could attenuate SPI1 depletion-imposed inhibition of autophagy and osteogenic differentiation of MC3T3-E1 cells. Conclusion: Our findings demonstrate that the SPI1/SMAD5 cascade, with the ability to enhance osteogenic differentiation, underlies the promoting effect of icariin on osteogenic differentiation of MC3T3-E1 cells. In dexamethasone-stimulated murine pre-osteoblast MC3T3-E1 cells, icariin upregulates SPI1 and thus enhances SMAD5 transcription, leading to enhanced autophagy and osteogenic differentiation of MC3T3-E1 cells. [ABSTRACT FROM AUTHOR]

Objective: Extracellular vesicles (EVs) have been shown to play a critical role in promoting tumorigenesis. As EV research grows, it is of importance to have standardization of isolation, quality control, characterization and validation methods across studies along with reliable references to explore troubleshooting solutions. Therefore, our objective with this Research Note was to isolate EVs from multiple breast cancer cell lines and to describe and perform protocols for validation as outlined by the list of minimal information for studies of EVs (MISEV) from the International Society for Extracellular Vesicles. Results: To isolate EVs, two techniques were employed: ultracentrifugation and size exclusion chromatography. Ultracentrifugation yielded better recovery of EVs in our hands and was therefore used for further validation. In order to satisfy the MISEV requirements, protein quantification, immunoblotting of positive (CD9, CD63, TSG101) and negative (TGFβ1, β-tubulin) markers, nanoflow cytometry and electron microscopy was performed. With these experiments, we demonstrate that yield of validated EVs varied between different breast cancer cell lines. Protocols were optimized to accommodate for low levels of EVs, and various technical and troubleshooting suggestions are included for potential application to other cell types that may provide benefit to investigators interested in future EV studies. [ABSTRACT FROM AUTHOR]

Archived patient-derived tissue specimens play a central role in understanding disease and developing therapies. To address specificity and sensitivity shortcomings of existing single-cell resolution proteoform analysis tools, we introduce a hybrid microfluidic platform (DropBlot) designed for proteoform analyses in chemically fixed single cells. DropBlot serially integrates droplet-based encapsulation and lysis of single fixed cells, with on-chip microwell-based antigen retrieval, with single-cell western blotting of target antigens. A water-in-oil droplet formulation withstands the harsh chemical (SDS, 6 M urea) and thermal conditions (98 °C, 1-2 hr) required for effective antigen retrieval, and supports analysis of retrieved protein targets by single-cell electrophoresis. We demonstrate protein-target retrieval from unfixed, paraformaldehyde-fixed (PFA), and methanol-fixed cells. Key protein targets (HER2, GAPDH, EpCAM, Vimentin) retrieved from PFA-fixed cells were resolved and immunoreactive. Relevant to biorepositories, DropBlot profiled targets retrieved from human-derived breast tumor specimens archived for six years, offering a workflow for single-cell protein-biomarker analysis of sparing biospecimens. Archived patient-derived tissue specimens play a central role in understanding disease and developing therapies. Here authors present DropBlot, a microfluidic platform that integrates droplet-based antigen retrieval with single-cell immunoblotting, enabling efficient protein retrieval and proteoform separation from fixed human specimens. [ABSTRACT FROM AUTHOR]

Background: Isoelectric focusing (IEF) is a method with an exquisite resolution, and coupled with affinity immunoblotting (AIB), it can provide superior sensitivity to detect monoclonal free light chains (FLC). Methods: We tested the hypothesis that IEF/AIB is more sensitive and specific for monoclonal FLC detection in serum and urine samples than conventional methods, that is, electrophoresis (ELP), immunofixation (IF) and serum FLC ratio assessment. Investigation included 107 samples of 68 patients, among which 21 multiple myeloma patients were recently tested for minimal residual disease and 18 patients with AL amyloidosis. Results: Monoclonal FLC were detected by IEF/AIB in 37% of serum samples negative for monoclonal FLC on ELP/IF. As for urine samples, significant advantage of the IEF/AIB over ELP/IF was not demonstrated. Considering both serum and urine results, IEF/AIB definitely revealed monoclonal FLC in 20/83 (24%) of ELP/IF-negative samples. FLC ratio was abnormally high (>1.65) in all 11 patients definitely positive for monoclonal FLC kappa by IEF/AIB but also in 16/47 (34%) IEF/AIB-negative samples. Abnormally low values (<0.26) were found only in 10/28 samples (36%) positive for monoclonal FLC lambda. Appropriate use of renal FLC ratio reference range reduced the number of presumably false positives (6/47, i.e. 13%) but not false negatives (17/28, i.e. 61%). Conclusions: The IEF/AIB method is more sensitive than IF and might be used in patients with negative IF results before deciding whether to proceed to minimal residual disease testing. [ABSTRACT FROM AUTHOR]

The adaption of plants to stressful environments depends on long-distance responses in plant organs, which themselves are remote from sites of perception of external stimuli. Jasmonic acid (JA) and its derivatives are known to be involved in plants' adaptation to salinity. However, to our knowledge, the transport of JAs from roots to shoots has not been studied in relation to the responses of shoots to root salt treatment. We detected a salt-induced increase in the content of JAs in the roots, xylem sap, and leaves of pea plants related to changes in transpiration. Similarities between the localization of JA and lipid transfer proteins (LTPs) around vascular tissues were detected with immunohistochemistry, while immunoblotting revealed the presence of LTPs in the xylem sap of pea plants and its increase with salinity. Furthermore, we compared the effects of exogenous MeJA and salt treatment on the accumulation of JAs in leaves and their impact on transpiration. Our results indicate that salt-induced changes in JA concentrations in roots and xylem sap are the source of accumulation of these hormones in leaves leading to associated changes in transpiration. Furthermore, they suggest the possible involvement of LTPs in the loading/unloading of JAs into/from the xylem and its xylem transport. [ABSTRACT FROM AUTHOR]

Objective To screen and identify new human sperm specific antigen epitopes from candidate sperm-specific antigen epitope peptides using phage display random peptide library technolog and bioinformatics methods. Methods Candidate sperm-specific epitope peptide monomers and trimers were synthesized by solid phase polypeptide synthesis. Dot immunoblotting and enzyme-linked immunosorbent assay (ELISA) were used to detect the immune reaction of the peptides with anti-sperm antibody (ASA) positive serum. ELISA was used to detect antibody titers against candidate sperm-specific epitope peptides in serum of immunized mice. The effects of the sera of the mice immunized with the candidate sperm-specific epitope peptide on human spermatozoa were examined by computer aided sperm analysis. Results High performance liquid chromatography and mass spectrometry showed that the purity and structure of the synthesized candidate sperm-specific epitope peptide were in accordance with the design. Blot and ELISA results indicated that the sperm-specific epitope peptide with the amino acid sequence n-TRRIHRHMTIRR-c and its trimers displayed strong immune response to 17 of 35 ASA positive sera. The serum from mice immunized with the peptide and its trimers significantly attenuated the sperm motility parameters compared with serum from the control group (P < 0. 05), with trimeric-induced decrease in motility parameters being particularly significant. (P<0.01). Conclusion The dodecapeptide with amino acid sequence n-TRRIHRHMTIRR-c is a novel human sperm-specific epitope peptide. [ABSTRACT FROM AUTHOR]

Literature reports suggest that the presence of proteins in pomegranate seeds is responsible for sensitization and IgE-mediated allergic reactions. The objective of this study was the analysis of a pomegranate seed extract and the isolation and characterization of proteins contained in high amounts. The extract characterization showed a protein profile with main bands at about 18 kDa and below 10 kDa upon SDS-PAGE, and molecules were recognized by specific IgEs upon immunoblotting. Then, two new 2S albumins, a monomeric and a heterodimeric one, were isolated by using classical biochemical methods. They were identified via direct protein sequencing and mass spectrometry, and their primary structure was analyzed and compared with homologous allergenic proteins via bioinformatics. In an Italian population of 703 suspected allergic patients, analyzed by using the FABER® test, the frequency of sensitization to the monomeric and heterodimeric 2S albumins was 1.7% and 0.28%, respectively. This study reports for the first time the isolation and characterization of two 2S albumins from pomegranate seeds. The clinical relevance of these molecules needs further investigation, for instance in populations having different exposures and allergy profiles. [ABSTRACT FROM AUTHOR]

The article titled "Correction to 'integrin‐linked kinase regulates endothelial cell nitric‐oxide synthase expression in hepatic sinusoidal endothelial cells'" by Shafiei et al. published in Liver International in April 2015 contains a correction regarding errors in the figures. The authors identified mistakes in the beta‐actin lanes of Figure 2A,C, and in the total AKT lane in Figure 6B. The revised figures are provided in the article. The authors apologize for the errors. [Extracted from the article]

Abstract Background Opisthorchiasis and cholangiocarcinoma (CCA) continue to be public health concerns in many Southeast Asian countries. Although the prevalence of opisthorchiasis is declining, reported cases tend to have a light-intensity infection. Therefore, early detection by using sensitive methods is necessary. Several sensitive methods have been developed to detect opisthorchiasis. The immunological detection of antigenic proteins has been proposed as a sensitive method for examining opisthorchiasis. Methods The Opisthorchis viverrini antigenic proteins, including cathepsin B (OvCB), asparaginyl endopeptidase (OvAEP), and cathepsin F (OvCF), were used to construct multi-antigenic proteins. The protein sequences of OvCB, OvAEP, and OvCF, with a high probability of B cell epitopes, were selected using BepiPred 1.0 and the IEDB Analysis Resource. These protein fragments were combined to form OvCB_OvAEP_OvCF recombinant DNA, which was then used to produce a recombinant protein in Escherichia coli strain BL21(DE3). The potency of the recombinant protein as a diagnostic target for opisthorchiasis was assessed using immunoblotting and compared with that of the gold standard method, the modified formalin-ether concentration technique. Results The recombinant OvCB_OvAEP_OvCF protein showed strong reactivity with total immunoglobulin G (IgG) antibodies against light-intensity O. viverrini infections in the endemic areas. Consequently, a high sensitivity (100%) for diagnosing opisthorchiasis was reported. However, cross-reactivity with sera from other helminth and protozoan infections (including taeniasis, strongyloidiasis, giardiasis, E. coli infection, enterobiasis, and mixed infection of Echinostome spp. and Taenia spp.) and no reactivity with sera from patients with non-parasitic infections led to a reduced specificity of 78.4%. In addition, the false negative rate (FNR), false positive rate (FPR), positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy were 0%, 21.6%, 81.4%, 100%, and 88.9%, respectively. Conclusions The high sensitivity of the recombinant OvCB_OvAEP_OvCF protein in detecting opisthorchiasis demonstrates its potential as an opisthorchiasis screening target. Nonetheless, research on reducing cross-reactivity should be undertaken by detecting other antibodies in other sample types, such as saliva, urine, and feces. Graphical Abstract

Objective: Myositis‐associated autoantibodies (MAAs) have been associated with overlap myositis, certain disease manifestations such as interstitial lung disease (ILD), and worse prognosis in the idiopathic inflammatory myopathies. MAAs overall remain largely uncharacterized in patients with juvenile‐onset myositis. Moreover, it is unknown whether the number of MAAs is associated with disease severity. Methods: Patients with juvenile myositis in cross‐sectional natural history studies who underwent testing for myositis autoantibodies were included. Demographics, myositis autoantibodies, clinical characteristics, medications received, and outcomes of those with and without MAAs were compared. Multivariable logistic regression was performed to determine whether the number of MAAs detected was associated with severe disease features. Results: Among 551 patients, 36% had an MAA and 13% had more than one MAA. Among those who were MAA positive, there was a higher frequency of overlap myositis (18% vs 5.9%, P < 0.001). MAA positivity was associated with certain clinical features, including Raynaud phenomenon (odds ratio [OR] 2.44, 95% confidence interval [CI] 1.41–4.28) and ILD (OR 3.43, 95% CI 1.75–6.96), as well as a chronic disease course (OR 1.72, 95% CI 1.10–2.72) and mortality (OR 3.76, 95% CI 1.72–8.43). The number of MAAs was also associated with mortality (OR 1.83, 95% CI 1.16–2.86). Conclusion: MAAs were prevalent in a large cohort of patients with juvenile myositis. ILD, refractory disease, and mortality were associated with MAA positivity. Prospective studies are needed to determine whether early detection of MAAs may lead to improved outcomes for patients with juvenile myositis. [ABSTRACT FROM AUTHOR]

Mitochondrial genes can be artificially relocalized in the nuclear genome in a process known as allotopic expression, such is the case of the mitochondrial cox2 gene, encoding subunit II of cytochrome c oxidase (C c O). In yeast, cox2 can be allotopically expressed and is able to restore respiratory growth of a cox2-null mutant if the Cox2 subunit carries the W56R substitution within the first transmembrane stretch. However, the COX2W56R strain exhibits reduced growth rates and lower steady-state C c O levels when compared to wild-type yeast. Here, we investigated the impact of overexpressing selected candidate genes predicted to enhance internalization of the allotopic Cox2W56R precursor into mitochondria. The overproduction of Cox20, Oxa1, and Pse1 facilitated Cox2W56R precursor internalization, improving the respiratory growth of the COX2W56R strain. Overproducing TIM22 components had a limited effect on Cox2W56R import, while overproducing TIM23-related components showed a negative effect. We further explored the role of the Mgr2 subunit within the TIM23 translocator in the import process by deleting and overexpressing the MGR2 gene. Our findings indicate that Mgr2 is instrumental in modulating the TIM23 translocon to correctly sort Cox2W56R. We propose a biogenesis pathway followed by the allotopically produced Cox2 subunit based on the participation of the 2 different structural/functional forms of the TIM23 translocon, TIM23MOTOR and TIM23SORT, that must follow a concerted and sequential mode of action to insert Cox2W56R into the inner mitochondrial membrane in the correct Nout–Cout topology. [ABSTRACT FROM AUTHOR]

Heat shock proteins (HSPs), which function as chaperones, are activated in response to various environmental stressors. In addition to their role in diverse aspects of protein production, HSPs protect against harmful protein-related stressors. Calycosin exhibits numerous beneficial properties. This study aims to explore the protective effects of calycosin in the heart under heat shock and determine its underlying mechanism. H9c2 cells, western blot, TUNEL staining, flow cytometry, and immunofluorescence staining were used. The time-dependent effects of heat shock analyzed using western blot revealed increased HSP expression for up to 2 h, followed by protein degradation after 4 h. Hence, a heat shock damage duration of 4 h was chosen for subsequent investigations. Calycosin administered post-heat shock demonstrated dose-dependent recovery of cell viability. Under heat shock conditions, calycosin prevented the apoptosis of H9c2 cells by upregulating HSPs, suppressing p-JNK, enhancing Bcl-2 activation, and inhibiting cleaved caspase 3. Calycosin also inhibited Fas/FasL expression and activated cell survival markers (p-PI3K, p-ERK, p-Akt), indicating their cytoprotective properties through PI3K/Akt activation and JNK inhibition. TUNEL staining and flow cytometry confirmed that calycosin reduced apoptosis. Moreover, calycosin reversed the inhibitory effects of quercetin on HSF1 and Hsp70 expression, illustrating its role in enhancing Hsp70 expression through HSF1 activation during heat shock. Immunofluorescence staining demonstrated HSF1 translocation to the nucleus following calycosin treatment, emphasizing its cytoprotective effects. In conclusion, calycosin exhibits pronounced protective effects against heat shock-induced damages by modulating HSP expression and regulating key signaling pathways to promote cell survival in H9c2 cells. [ABSTRACT FROM AUTHOR]

Hyperglycemia induces chronic stresses, such as oxidative stress and endoplasmic reticulum (ER) stress, which can result in β -cell dysfunction and development of Type 2 Diabetes Mellitus (T2DM). Ginsenoside Rk1 is a minor ginsenoside isolated from Ginseng. It has been shown to exert anti-cancer, anti-inflammatory, anti-oxidant, and neuroprotective effects; however, its effects on pancreatic cells in T2DM have never been studied. This study aims to examine the novel effects of Ginsenoside Rk1 on ER stress-induced apoptosis in a pancreatic β -cell line MIN6 and HFD-induced diabetic pancreas, and their underlying mechanisms. We demonstrated that Ginsenoside Rk1 alleviated ER stress-induced apoptosis in MIN6 cells, which was accomplished by directly targeting and activating insulin-like growth factor 1 receptor (IGF-1R), thus activating the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/Bcl-2-associated agonist of cell death (Bad)-B-cell lymphoma-2 (Bcl-2) pathway. This pathway was also confirmed in an HFD-induced diabetic pancreas. Meanwhile, the use of the IGF-1R inhibitor PQ401 abolished this anti-apoptotic effect, confirming the role of IGF-1R in mediating anti-apoptosis effects exerted by Ginsenoside Rk1. Besides, Ginsenoside Rk1 reduced pancreas weights and increased pancreatic insulin contents, suggesting that it could protect the pancreas from HFD-induced diabetes. Taken together, our study provided novel protective effects of Ginsenoside Rk1 on ER stress-induced β -cell apoptosis and HFD-induced diabetic pancreases, as well as its direct target with IGF-1R, indicating that Ginsenoside Rk1 could be a potential drug for the treatment of T2DM. [ABSTRACT FROM AUTHOR]

BACKGROUND: Although sodium-glucose cotransporter-2 inhibitors have been shown to improve cardiovascular outcomes in general, little is presently known about any sex-specific changes that may result from this therapy. We sought to investigate and quantify potential sex-specific changes seen with the sodium-glucose cotransporter-2 inhibitor canagliflozin (CAN) in a swine model of chronic myocardial ischemia. STUDY DESIGN: Eighteen Yorkshire swine underwent left thoracotomy with placement of an ameroid constrictor. Two weeks postop, swine were assigned to receive either control (F = 5 and M = 5) or CAN 300 mg daily (F = 4 and M = 4). After 5 weeks of therapy, swine underwent myocardial functional measurements, and myocardial tissue was sent for proteomic analysis. RESULTS: Functional measurements showed increased cardiac output, stroke volume, ejection fraction, and ischemic myocardial flow at rest in male swine treated with CAN compared with control male swine (all p < 0.05). The female swine treated with CAN had no change in cardiac function as compared with control female swine. Proteomic analysis demonstrated 6 upregulated and 97 downregulated proteins in the CAN female group compared with the control female group. Pathway analysis showed decreases in proteins in the tricarboxylic acidic cycle. The CAN male group had 639 upregulated and 172 downregulated proteins compared with control male group. Pathway analysis showed increases in pathways related to cellular metabolism and decreases in pathways relevant to the development of cardiomyopathy and to oxidative phosphorylation. CONCLUSIONS: Male swine treated with CAN had significant improvements in cardiac function that were not observed in female swine treated with CAN. Moreover, CAN treatment in male swine was associated with significantly more changes in protein expression than in female swine treated with CAN. The increased proteomic changes seen in the CAN male group likely contributed to the more robust changes in cardiac function seen in male swine treated with CAN. [ABSTRACT FROM AUTHOR]

Anti-mitochondrial antibody (AMA) is not always present in patients with primary biliary cholangitis (PBC). We aimed to determine the additional value of anti-hexokinase 1 (anti-HK1) and anti-kelch-like 12 (anti-KLHL12) antibody in PBC and analyzed the biochemical and immunological parameters of 212 subjects, including PBC patients and healthy controls. Serum anti-gp210 and sp100 antibodies were determined by an immunoblotting test (IBT). Enzyme-linked immunosorbent assay (ELISA) was employed to evaluate anti-HK1 and anti-KLHL12. The diagnostic value of anti-HK1 and anti-KLHL12 to PBC was analyzed by constructing a receiver operating characteristic (ROC) curve. ROC analyses didn't show a very good performance of serum anti-HK1 for PBC diagnosis; the AUC was 0.664 with a sensitivity of 53.3 % and a specificity of 79.2 %. Regarding anti-KLHL12, ROC analysis yielded an AUC of 0.626, with a sensitivity of 45.7 % and a specificity of 93.8 %. For AMA-negative PBC patients, the AUC increased to 0.790 for KLHL12, and 0.708 for HK1. AMA combined with anti-HK1 or anti-KLHL12 antibody significantly improved the diagnostic sensitivity of PBC from 82 to about 95 %, respectively. In AMA-negative PBC patients, the sensitivities for anti-HK1 (62.50 %) and anti-KLHL12 (75 %) antibodies were higher than for anti-gp210 (37.5 %) and anti-sp100 antibody (43.75 %). When these four antibodies were combined, the overall sensitivity increased to 87.5 %. The determination of anti-HK1 and anti-KLHL12 facilitates the diagnosis of PBC, particularly in AMA-negative patients. Adding anti-HK1 and anti-KLHL12 antibodies to clinical detection enables early diagnosis and timely treatment, potentially improving patient prognosis. [ABSTRACT FROM AUTHOR]

Background: Intervertebral disc degeneration (IDD) is an increasingly important cause of low back pain (LBP) that results in substantial health and economic burdens. Inflammatory pathway activation and the production of reactive oxygen species (ROS) play vital roles in the progression of IDD. Several studies have suggested that phillyrin has a protective role and inhibits inflammation and the production of ROS. However, the role of phillyrin in IDD has not been confirmed. Purpose: The purpose of this study was to investigate the role of phillyrin in IDD and its mechanisms. Study design: To establish IDD models in vivo, ex-vivo, and in vitro to verify the function of phillyrin in IDD. Method: The effects of phillyrin on extracellular matrix (ECM) degeneration, inflammation, and oxidation in nucleus pulposus (NP) cells were assessed using immunoblotting and immunofluorescence analysis. Additionally, the impact of phillyrin administration on acupuncture-mediated intervertebral disc degeneration (IDD) in rats was evaluated using various techniques such as MRI, HE staining, S-O staining, and immunohistochemistry (IHC). Result: Pretreatment with phillyrin significantly inhibited the IL-1β-mediated reduction in the degeneration of ECM and apoptosis by alleviating activation of the NF-κB inflammatory pathway and the generation of ROS. In addition, in vivo and ex-vivo experiments verified the protective effect of phillyrin against IDD. Conclusion: Phillyrin can attenuate the progression of IDD by reducing ROS production and activating inflammatory pathways. [ABSTRACT FROM AUTHOR]

Background. Stevens–Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare and potentially life-threatening mucocutaneous blistering diseases that clinically can resemble autoimmune bullous diseases. Moreover, it has been shown that autoantibodies against epidermal proteins are present in SJS/TEN. Objectives. To establish the presence of antibodies against desmosomal and hemidesmosomal proteins in confirmed SJS/TEN patients. Methods. Serum of SJS/TEN patients diagnosed based on clinical criteria, e.g., epidermal detachment with erosions and severe mucosal lesions, (suspicion of) a culprit drug, and matching histologic results was evaluated by various techniques, e.g., indirect immunofluorescence on monkey esophagus, salt split skin and rat bladder, immunoblotting (IB) and immunoprecipitation (IP), ELISAs against desmogleins and BP180, keratinocyte footprint assay, and keratinocyte binding assay. Results. A total of 28 patients were included in this study, 15 men and 13 women with a mean age of 56 years. In most patients, none of the serological tests were positive. In two patients, an elevated DSG3 titer was found suspicious for pemphigus vulgaris. Three patients had elevated NC16a titers, suggesting bullous pemphigoid. However, in all these patients, no other tests were positive and in these patients, the biopsy for direct immunofluorescence showed no evidence for an autoimmune bullous disease. Three patients showed reactivity against rat bladder rat bladder; these were, however, completely negative for A2ML1, envoplakin, and periplakin in the IB as well as the IP. Conclusions. Serological analysis for desmosomal and hemidesmosomal antibodies is reliable to rule an autoimmune bullous disease in patients with suspected SJS/TEN. However, one should not rely on one single test method since false positive results can occur. Moreover, this study also makes it less plausible that antibodies against desmosomal and/or hemidesmosomal components are involved in the pathogenesis of SJS/TEN. [ABSTRACT FROM AUTHOR]

Background Opisthorchiasis and cholangiocarcinoma (CCA) continue to be public health concerns in many South- east Asian countries. Although the prevalence of opisthorchiasis is declining, reported cases tend to have a light- intensity infection. Therefore, early detection by using sensitive methods is necessary. Several sensitive methods have been developed to detect opisthorchiasis. The immunological detection of antigenic proteins has been proposed as a sensitive method for examining opisthorchiasis. Methods The Opisthorchis viverrini antigenic proteins, including cathepsin B (OvCB), asparaginyl endopeptidase (OvAEP), and cathepsin F (OvCF), were used to construct multi-antigenic proteins. The protein sequences of OvCB, OvAEP, and OvCF, with a high probability of B cell epitopes, were selected using BepiPred 1.0 and the IEDB Analysis Resource. These protein fragments were combined to form OvCB_OvAEP_OvCF recombinant DNA, which was then used to produce a recombinant protein in Escherichia coli strain BL21(DE3). The potency of the recombinant protein as a diagnostic target for opisthorchiasis was assessed using immunoblotting and compared with that of the gold standard method, the modified formalin-ether concentration technique. Results The recombinant OvCB_OvAEP_OvCF protein showed strong reactivity with total immunoglobulin G (IgG) antibodies against light-intensity O. viverrini infections in the endemic areas. Consequently, a high sensitivity (100%) for diagnosing opisthorchiasis was reported. However, cross-reactivity with sera from other helminth and protozoan infections (including taeniasis, strongyloidiasis, giardiasis, E. coli infection, enterobiasis, and mixed infection of Echi- nostome spp. and Taenia spp.) and no reactivity with sera from patients with non-parasitic infections led to a reduced specificity of 78.4%. In addition, the false negative rate (FNR), false positive rate (FPR), positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy were 0%, 21.6%, 81.4%, 100%, and 88.9%, respectively. Conclusions The high sensitivity of the recombinant OvCB_OvAEP_OvCF protein in detecting opisthorchiasis demonstrates its potential as an opisthorchiasis screening target. Nonetheless, research on reducing cross-reactivity should be undertaken by detecting other antibodies in other sample types, such as saliva, urine, and feces. [ABSTRACT FROM AUTHOR]

We assessed the effects of two levels of calorie restriction (CR; eating either 15% or 35% less than ad libitum, AL, food intake for 8 weeks) by 24-month-old female and male rats on glucose uptake (GU) and phosphorylation of key signaling proteins (Akt; AMP-activated protein kinase, AMPK; Akt substrate of 160 kDa, AS160) measured in isolated skeletal muscles that underwent four incubation conditions (without either insulin or AICAR, an AMPK activator; with AICAR alone; with insulin alone; or with insulin and AICAR). Regardless of sex: (1) neither CR group versus the AL group had greater GU by insulin-stimulated muscles; (2) phosphorylation of Akt in insulin-stimulated muscles was increased in 35% CR versus AL rats; (3) prior AICAR treatment of muscle resulted in greater GU by insulin-stimulated muscles, regardless of diet; and (4) AICAR caused elevated phosphorylation of acetyl CoA carboxylase, an indicator of AMPK activation, in all diet groups. There was a sexually dimorphic diet effect on AS160 phosphorylation, with 35% CR exceeding AL for insulin-stimulated muscles in male rats, but not in female rats. Our working hypothesis is that the lack of a CR-effect on GU by insulin-stimulated muscles was related to the extended duration of the ex vivo incubation period (290 min compared to 40–50 min that was previously reported to be effective). The observed efficacy of prior treatment of muscles with AICAR to improve glucose uptake in insulin-stimulated muscles supports the strategy of targeting AMPK with the goal of improving insulin sensitivity in older females and males. [ABSTRACT FROM AUTHOR]

Objective Autoantibodies against MDA5 (melanoma differentiation-associated protein 5) serve as a biomarker for DM (dermatomyositis) and indicate a risk factor for interstitial lung disease (ILD). MDA5 is a protein responsible for sensing RNA virus infection and activating signalling pathways against it. However, little is known about the antigen epitopes on MDA5 autoantibodies. We aimed to determine the interaction of the MDA5 autoantibody–antigen epitope. Methods Cell-based assays (CBAs), immunoprecipitation-immunoblot assays, and various immunoblotting techniques were used in the study. Results We demonstrated that DM patient autoantibodies recognize MDA5 epitopes in a native conformation–dependent manner. Furthermore, we identified the central helicase domain （3Hel） formed by Hel1, Hel2i, Hel2, and pincer as the major epitopes. As proof of principle, the purified 3Hel efficiently absorbed MDA5 autoantibodies from patient sera through immunoprecipitation-immunoblot assay. Conclusion Our study uncovered the nature of the antigen epitopes on MDA5 and can provide guidance for diagnosis and a targeted therapeutic approach development. [ABSTRACT FROM AUTHOR]