Surrogate Biomarker Research Articles

Early Monitoring of Donor-Derived Cell-Free DNA in Kidney Allograft Recipients Followed-Up for Two Years: Experience of One Center

(1) Background: donor-derived circulating free DNA (dd-cfDNA), an innovative biomarker with great potential for the early identification and prevention of graft damage. (2) Methods: Samples were collected prospectively and the study was performed retrospectively to analyze dd-cfDNA plasma levels in 30 kidney transplant patients during their post-transplant follow-up (15 days, 3, 6, and 9 months), to determine if the result could be of interest in the identification of possible adverse events, especially rejection. The aim was to verify whether the data on sensitivity, specificity, NPV, and PPV compare with reference values and creatinine values. (3) Results: We observed levels of dd cfDNA > 1% in six of nine patients with active rejection (ABMR or TCMR) and elevated values (>0.5%) in two other patients in this rejection group. Our results show low values of sensitivity = 50%, specificity = 61.11%, rejection NPV = 64.71%, and rejection PPV = 46.13% of the technique compared to reference values previously published. With respect to creatinine, only for TCRM, we observed better results for dd-cfDNA in these parameters than in creatinine. Also, our data suggest that dd-cfDNA could help to differentiate those patients with dnDSAs that are going to through rejection better than creatinine, specially at 15 d post transplant. In this study, this appears to have no positive predictive value for borderline rejection (BR) or TCMR IA. (4) Conclusions: plasma levels of dd-cfDNA could be considered an additional or alternative biomarker for graft rejection monitoring in early post-kidney transplant up to several months before its clinical presentation, especially for patients with suspected TCMR or ABMR.

Identifying amyotrophic lateral sclerosis using diffusion tensor imaging, and correlation with neurofilament markers.

To determine diagnostic value of diffusion tensor imaging (DTI) in amyotrophic lateral sclerosis (ALS) patients and investigate the association between DTI and neurofilaments (NFs), including serum and cerebrospinal fluid (CSF) levels of neurofilament light chain (NFL) and phosphorylated neurofilament heavy chain (pNFH). Forty-three clinically diagnosed ALS patients and 32 control subjects without neurological disorders underwent routine MRI (magnetic resonance imaging) and DTI scans. DTI parameters (mean diffusivity [MD] and fractional anisotropy [FA]) at axial levels of internal capsules and cerebral peduncles along the corticospinal tract (CST) were measured. The study compared the differences of DTI parameters between ALS patients and controls using the Mann-Whitney U test. Diagnostic efficacy of each DTI metric was evaluated using the receiver operating characteristic (ROC) curve. NFs (NFL and pNFH levels in serum and CSF) were measured by enzyme-linked immunosorbent assay. Correlation analyses were conducted between DTI parameters and NFs. Capsule-MD and Peduncle-MD in ALS patients were higher than those in controls; whereas Capsule-FA and Peduncle-FA in ALS patients were lower than those in controls (all, p < 0.05). The area under curve (AUC) was 0.730 for Capsule-FA, 0.828 for Capsule-MD, 0.890 for Peduncle-FA, and 0.896 for Peduncle-MD. Capsule-FA was negatively correlated with CSF-NFL (r = -0.813, p < 0.001), Serum-NFL (r = -0.493, p = 0.001), CSF-pNFH (r = -0.637, p < 0.001), and Serum-pNFH (r = -0.672, p < 0.001); Peduncle-FA negatively with CSF-NFL (r = -0.562, p < 0.001), CSF-pNFH (r = -0.506, p = 0.001), and Serum-pNFH (r = -0.488, p = 0.001); Peduncle-MD positively with CSF-NFL (r = 0.516, p < 0.001), CSF-pNFH (r = 0.494, p = 0.001). DTI had superior performance in identifying ALS patients and could serve as a reliable predictor. DTI parameters related to neurofilament markers, and Capsule-FA may become a robust surrogate biomarker indicating disease severity and progression rate for ALS patients.

Abstract A008: Identification of EYA2 as a promising biomarker for DICER1-related tumor predisposition

Abstract Background: DICER1-related tumor predisposition (DRTP), also known as DICER1 syndrome, is a genetic condition associated with an increased risk of developing various tumors, including pleuropulmonary blastoma, thyroid gland neoplasia, ovarian tumors, and cystic nephroma. Currently, the diagnosis and surveillance of DRTP primarily relies on genetic testing for DICER1 mutations. There is a pressing need for surrogate diagnostic biomarkers to improve early detection and monitoring. Objective: To identify and validate EYA2 as a potential biomarker for DICER1-related tumor predisposition. Methods: Murine mesenchymal stromal cell lines were developed to model the consequences of DICER1 mutations, including the DICER1E1705K mutation found in DRTP. Both bulk RNA sequencing (RNAseq) and microRNA sequencing (miRNAseq) were employed to identify differentially expressed mRNAs in these cell lines. The RNA and protein levels of Eya2 were measured by qRT-PCR and Western blot, respectively. De-repression of Eya2 mRNA by miRNA was evaluated by dual luciferase assay to link overexpression with the DICER1 defect of DRTP. Then, immunohistochemistry staining of EYA2 was performed on a panel of DRTP tumors. Results: We found that more than 2000 mRNAs were derepressed in mesenchymal stromal cells expressing DICER1E1705K as compared to DICER1WT. Among these, Eya2 emerged as a top candidate. We observed elevated Eya2 mRNA and protein levels in DICER1E1705K -expressing mesenchymal stromal cells. Utilizing a reporter assay, we also observed de-repression of the 3’ UTR of Eya2 upon expression of DICER1E1705K as compared to DICER1WT. Strong nuclear EYA2 staining was observed in a subset of DRTP tumor samples. Conclusion: Elevated EYA2 expression in tumor tissues from DRTP patients supports its potential use in both diagnostic and surveillance contexts. Further studies are warranted to validate EYA2 as a clinical biomarker and explore its utility in improving early detection and monitoring strategies for individuals at risk of DRTP. Citation Format: Mona Wu, Shengmei Zhou, Felix Kommoss, Yemin Wang, James F Amatruda. Identification of EYA2 as a promising biomarker for DICER1-related tumor predisposition [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: RNAs as Drivers, Targets, and Therapeutics in Cancer; 2024 Nov 14-17; Bellevue, Washington. Philadelphia (PA): AACR; Mol Cancer Ther 2024;23(11_Suppl):Abstract nr A008.

Abstract B061: Assessing saliva for cancer biomarker discovery: A liquid biopsy approach

Abstract Introduction: Liquid biopsy has been gaining traction as a replacement for invasive tumor biopsies in oncology. Several blood-based in vitro diagnostics have been approved by the FDA and other regulatory agencies, and efforts are being made to validate urine, saliva, and buccal swabs as alternative matrices. The primary aim of this study was to investigate the relative mRNA expression in paired blood and saliva samples from cancer patients and healthy individuals. Methods: We collected matched saliva and blood samples from 35 subjects, comprising 26 patients with prostate, breast, colon, lung, melanoma, and pancreatic cancers, and 9 healthy individuals. Samples were collected using Wren's proprietary stabilization buffer kit, and total RNA extracted by TRIzol-based Qiagen reagents. RNA sequencing (RNA-Seq) was performed on a Novaseq 6000 platform, and data was analyzed using high-performance computing (HPC) with PartekFlow software, employing the BWA aligner (hg38). We focused on comparing gene expression in cancers (as a group) compared to controls. Results: The total number of genes detected in saliva was 3,985, compared to 14,459 genes detected in blood samples. A substantial overlap was observed, with more than 92.8% of saliva-detected genes also found in blood. We also examined housekeeping gene detection in both matrices. In this set of 1,003 housekeeping genes, 30% (n=305) were expressed in both saliva and blood. When we narrowed the scope to only include the 1,154 cancer-related genes as listed by the OncoKB database, 88.3% were detected in saliva and/or blood, with 37.1% of these genes (n=429) were expressed in both saliva and blood. Lastly, we examined a set of 241 cancer-associated biomarkers utilized in RT-PCR-based diagnostic blood assays clinically validated by our laboratory. This subset analysis revealed that 23.2% of these biomarkers were expressed in both saliva and blood. Conclusion: Our data indicate that the majority of mRNA detected in saliva was also detected in blood, with differential expression observed in cancer patients compared to normal controls. Given the relatively high limit of detection (low sensitivity) using RNA-Seq technology compared to PCR and the relatively small number of subjects, the data may suggest that saliva could function as a surrogate biomarker matrix for blood. Citation Format: Srinivas V Koduru, Mark Kidd, Abdel B Halim. Assessing saliva for cancer biomarker discovery: A liquid biopsy approach [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr B061.

Truncated Albumins as Novel Surrogate Biomarkers in Diabetes Therapy: Epiphenomena and Potential Clinical Applications.

Aims/Hypothesis: Among various albumin posttranslational modifications (PTMs), N- and C-terminal truncations (HSA-DA and HSA-L) have also shown biomarker potential in disease states. We examined albumin truncation longitudinal trends and correlations during diabetes therapy toward possible future clinical applications. Methods: In a preliminary longitudinal therapy investigation, mass spectrometry was employed to track PTMs of human serum albumin (HSA), including glycation (GA), cysteinylation (CA or HNA1; reversible), di/trioxidation (OA or HNA2; irreversible), and truncation (TA). These modifications were correlated with ongoing therapy in four distinct subject groups: type 1 diabetes (T1DM), type 2 diabetes (T2DM), prediabetes-obesity (PDOB), and healthy controls (NORM), observed over a follow-up period extending up to 280 days. Results: Diabetes was associated with significant reduction ("deficiency") of measured albumin truncations (For HSA-DA: T2DM = 0.32 ± 0.3%, p = 2E-08; T1DM = 1.02 ± 0.4%, p = 3E-05; PDOB = 1.61 ± 0.2%, p = 0.004; compared to NORM = 2.08 ± 0.2%). Albumin truncation reduction was more striking in T2DM (HSA-DA: T2DM vs. T1DM: p = 0.004). Improvements in glycemic control and decrease of albumin glycation during diabetes therapy were associated with concomitant increase of albumin truncations toward the "healthy" normal ranges, and vice versa ("mirror image" trends). Accordingly, albumin truncation correlated inversely with albumin glycation (HSA-DA vs. GA: R = -0.53, p = 1E-09). Conclusions: The "epiphenomenon" of albumin truncation (reflecting the severity of mean hyperglycemia and also insulin resistance) can possibly provide novel, sensitive, and complementary biomarkers (e.g., via simpler HSA-DA peptide fragment immunoassays) to monitor efficacy of diabetes therapy and also progression from "healthy" to prediabetes and type 2 diabetes, highlighting potential diagnostic and prognostic utility in clinical diabetes care.

Functional and vascular neuroimaging in maritime pilots with long-term sleep disruption.

The mechanism underlying the possible causal association between long-term sleep disruption and Alzheimer's disease remains unclear Musiek et al. 2015. A hypothesised pathway through increased brain amyloid load was not confirmed in previous work in our cohort of maritime pilots with long-term work-related sleep disruption Thomas et al. Alzheimer's Res Ther 2020;12:101. Here, using functional MRI, T2-FLAIR, and arterial spin labeling MRI scans, we explored alternative neuroimaging biomarkers related to both sleep disruption and AD: resting-state network co-activation and between-network connectivity of the default mode network (DMN), salience network (SAL) and frontoparietal network (FPN), vascular damage and cerebral blood flow (CBF). We acquired data of 16 maritime pilots (56 ± 2.3years old) with work-related long-term sleep disruption (23 ± 4.8 working years) and 16 healthy controls (59 ± 3.3years old), with normal sleep patterns (Pittsburgh Sleep Quality Index ≤ 5). Maritime pilots did not show altered co-activation in either the DMN, FPN, or SAL and no differences in between-network connectivity. We did not detect increased markers of vascular damage in maritime pilots, and additionally, maritime pilots did not show altered CBF-patterns compared to healthy controls. In summary, maritime pilots with long-term sleep disruption did not show neuroimaging markers indicative of preclinical AD compared to healthy controls. These findings do not resemble those of short-term sleep deprivation studies. This could be due to resiliency to sleep disruption or selection bias, as participants have already been exposed to and were able to deal with sleep disruption for multiple years, or to compensatory mechanisms Mentink et al. PLoS ONE. 2021;15(12):e0237622. This suggests the relationship between sleep disruption and AD is not as strong as previously implied in studies on short-term sleep deprivation, which would be beneficial for all shift workers suffering from work-related sleep disruptions.

BIOM-36. DETECTION OF CIRCULATING TUMOR DNA (CTDNA) IN CEREBROSPINAL FLUID (CSF) IN PATIENTS WITH GLIOBLASTOMA TREATED IN PHASE I CLINICAL TRIAL

Abstract BACKGROUND As circulating tumor DNA (ctDNA) has been shown to be a source of tumor-specific biomarkers, liquid biopsy has emerged as a novel noninvasive tool in diagnosis, disease monitoring and treatment selection in several solid tumors. However, its use in brain tumors remains challenging because ctDNA is commonly not detected in blood. Thus, CSF (cerebrospinal fluid) has emerged as a potential source of ctDNA in the context of brain tumors. PATIENTS AND METHODS We prospectively evaluated the detection of ctDNA in CSF (CSF-ctDNA) +/- blood of patients with pre-treated MTAP-deleted glioblastoma, currently treated in a phase I clinical trial evaluating PRMT5 inhibitors. We did CSF samples at C2D15 and at progression, after patient’s oral and written consent. CSF was collected by lumbar puncture and analyzed with a panel of 35 genes including IDH1-2, TERT promoter and EGFR. Blood was collected, synchronously with CSF, by peripheral veinous punction and analyzed with the Foundation One Liquid CDx panel. RESULTS Between January and April 2024, five patients were included. All of them undergone initial surgical resection and received at least one previous systemic treatment associated with radiotherapy. At least one somatic mutation was identified in each patient, including EGFR amplification in 2/5 patients (40%). CSF was not available at baseline. One patient provided CSF only at progression. Four patients provided CSF at C2D15 on treatment, and among them, one patient was also collected at progression. At data cut-off, one patient was still on treatment. We identified a detectable level of CSF-ctDNA in only one patient with occipital tumor localization, with detection of EGFR amplification known at diagnosis. Synchronous blood analysis showed only clonal hematopoiesis variants. CONCLUSION We showed in this small cohort of patients that detection of CSF-ctDNA is technically feasible. The type of panel used might be optimized for this population especially to monitor patients as a potential surrogate biomarker for treatment response.

Isotretinoin increases non-insulin-based surrogate markers of insulin resistance in acne vulgaris patients

Background Lipid indices, particularly the triglyceride-glucose index (TyG index) and the triglyceride/high-density lipoprotein cholesterol (TG/HDL-C) ratio, are simple, reliable, non-insulin-based surrogate markers of insulin resistance that have recently gained prominence. The aim of this study was to evaluate the effect of isotretinoin treatment on surrogate markers of insulin resistance, in particular the TyG index, in patients with acne vulgaris (AV). Materials and methods This retrospective study reviewed the records of 200 patients who received isotretinoin treatment for acne vulgaris at the Department of Dermatology and Venereology between September 2023 and March 2024. Serum fasting glucose, fasting lipid profile [triglyceride (TG), total cholesterol (TC), very low-density lipoprotein cholesterol (VLDL-C), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C)] and other biochemical parameters were recorded. Triglyceride-glucose (TyG) index value was calculated with the formula Ln [fasting triglyceride (mg/dL) × fasting plasma glucose (mg/dL)/2]. Pre-treatment values were compared with values after 5 months of treatment. Results TyG index and TG/HDL, TC/HDL, and LDL/HDL ratios all increased statistically significantly (p < 0.001). In addition, a positive correlation was found between pre- and post-treatment TyG index values and pre- and post-treatment TC/HDL, LDL/HDL and TG/HDL ratio values (p < 0.001). Among lipid measurements, triglycerides, total cholesterol, VLDL-C, LDL-C increased statistically significantly (p < 0.001), while HDL-C decreased statistically significantly (p < 0.05). Conclusion The results of this study suggest that isotretinoin treatment may increase insulin resistance in AV patients by increasing surrogate biomarkers of insulin resistance. We also suggest that the TyG index and other lipid indices can be used in treatment follow-up.

Hypothalamic-Pituitary-Adrenal Axis Activity and Metabolic Disorders in Kidney Transplant Recipients on Long-Term Glucocorticoid Therapy

Background/Objectives: Glucocorticoids are commonly used for maintenance immunosuppressive therapy in kidney transplant recipients (KTRs). We aimed to investigate the prevalence of hypothalamic-pituitary-adrenal (HPA) axis suppression and its association with metabolic disorders in stable KTRs on low-dose glucocorticoids. Methods: This cross-sectional study included adult KTRs on low-dose glucocorticoids. HPA axis suppression was defined as baseline morning cortisol &lt; 5 μg/dL. Adrenocorticotropic hormone (ACTH), dehydroepiandrosterone-sulphate (DHEAS) and 24 h urinary free cortisol (UFC) levels were also assessed. Examined metabolic disorders included hypertension, dyslipidemia, central obesity and post-transplant diabetes mellitus (PTDM). Results: Eighty adult KTRs with a median 57 months (IQR 24–102) since transplantation were included in the study. The mean prednisolone dose was 5.0 ± 1.3 mg/day. Baseline cortisol &lt; 5.0 μg/dL was observed in 27.5% of the KTRs. Participants with baseline cortisol &lt; 5.0 μg/dL were older (55.1 vs. 47.4 years, p = 0.023) and had had a transplant for a longer time (101.4 vs. 67.0 months, p = 0.043), compared with the rest of the cohort. Baseline cortisol correlated positively with ACTH (rho = 0.544, p &lt; 0.001), DHEAS (rho:0.459, p &lt; 0.001) and UFC (rho: 0.377, p = 0.002). The area under the receiver-operating characteristic curve for ACTH as a predictor of baseline cortisol &gt; 5.0 μg/dL was 0.79 [95% confidence interval (CI): 0.68–0.89]. After adjustment for covariates, HPA axis suppression was not associated with the examined metabolic disorders. Conclusions: Our study showed that stable KTRs on chronic low-dose glucocorticoids exhibited an increased prevalence of HPA axis suppression. ACTH may serve as a surrogate biomarker for HPA axis activity in this population. Further research could evaluate the association of glucocorticoid-induced HPA axis inhibition with metabolic disorders.

SNORD3A: a new possible circulating biomarker of human heart failure

Abstract Background Heart failure (HF) is a complex clinical syndrome and the leading cause of mortality, morbidity and hospitalization in industrialized countries. Human cardiac biopsies are invaluable resources for identifying cardiac signaling pathways, however blood fractions and peripheral blood mononuclear cells (PBMCs) could be used as a source of surrogate biomarkers of signaling pathway activation in human heart failure. Purpose In the present study we aimed to identify novel circulating biomarkers mirroring human myocardial signaling in HF and to study the role played by SNORD3A in cardiomyocyte survival and death. Methods Cardiac left ventricle samples and PBLs from 8 HF patients undergoing heart transplantation and 2 control patients (CTRL) were analyzed by RNA sequencing (RNASeq) to identify transcripts that were regulated in both hearts and PBLs. Five identified transcripts, KCNQOT1, MIAT, SCRN1, MALAT1 and SNORD3A, were then validated by quantitative real-time PCR in PBMCs and in LVs. Next, we analyzed the expression of the Small Nucleolar RNA (snoRNA) SNORD3A in LVs and PBMCs from 8-week-old wild type C57BL/6 mice with pressure overload-induced HF by transverse aortic constriction (TAC). Sham-operated mice (sham) were used as controls. To further investigate the role of SNORD3A in cardiomyocyte function and survival, SNORD3A antisense oligonucleotides (SNOaso) and scramble control sequences (GFPaso) were synthesized and tested in cardiomyoblasts H9C2 cells under normoxic or hypoxic conditions to evaluate SNORD3A transcription levels, cell death and protein synthesis. Results SNORD3A expression was significantly increased in both LVs and PBMCs from HF patients compared to control subjects. Consistent with these results, SNORD3A levels were increased both in PBMCs and LVs from TAC mice compared to sham. In vitro hypoxia significantly increased SNORD3A expression levels in H9C2 cells, compared to normoxia. After SNOaso transfection, SNORD3A transcripts were downregulated, and they were further reduced following 3-hour-hypoxia. Depletion of SNORD3A levels increased cardiomyocyte death and reduced protein synthesis in H9C2 cells. Conclusions Our data suggest that SNORD3A might be involved in the regulation of cardiomyocyte survival in HF and could be useful for diagnostic and prognostic applications in HF.

Linking antibody against apolipoprotein A-1 to metabolic dysfunction-associated steatohepatitis in mice

Abstract Background Metabolic dysfunction-associated fatty liver disease (MASLD) is a common liver condition associated with increased cardiovascular disease (CVD) risk. Cytokeratin 18 (CK-18) is indicative of liver injury and used as a surrogate biomarker covering MASLD to cirrhosis phenotypes. Autoantibodies against apolipoprotein A-1 (AAA-1) are known CVD risk factors inducing MASLD in vitro, but their role in modulating steatohepatitis and fibrosis in vivo is still elusive. We investigated AAA-1's contribution to systemic low-grade inflammation, liver steatosis, and fibrosis using a MASLD mouse model and a validated passive immunization protocol (PIP). Methods 10 weeks-old male C57BL/6J mice were fed a choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) and immunized with AAA-1 (200ug) or control antibodies for ten days. At sacrifice, plasma samples were collected, and CK-18 levels, and proinflammatory cytokines were measured using the Mesoscale Discovery platform. Hematoxylin and Eosin and Sirius Red Fast Green staining were used to reveal liver steatosis and fibrosis, respectively. RNA were extracted from mouse liver samples and mRNA were then analyzed using a commercial fibrosis-specific genes panel (nCounter Human Fibrosis V2 Panel) and the nCounter Analysis System. Results Compared to control IgG recipients, CDAHFD mice injected with AAA-1 exhibited significantly elevated plasma levels of CK-18 (5.3 vs 2.1, p=0.031), IL-6 (13 vs 6.9, p=0.035), IL-10 (27.3 vs 9.8, p=0.007) and TNF-α (32.1 vs 24.2, p=0.032), and liver steatosis (93.4% vs 73.8%, p=0.007). Nanostring technology experiments revealed upregulation of several pro-fibrotic m-RNAs in liver tissue from AAA-1 immunized mice compared to the IgG immunized control group. These included Serum Amyloid A (Fold Change (FC) AAA-1 vs IgG : 2.5, p=0.02) , G-protein coupled receptors 65 (FC: 2.7, p=0.01), Periostin (FC: 2.6, p=0.001), Phospholipid transfer protein (FC: 2.2, p=0.0004), Vascular Cell Adhesion Molecule 1 (FC: 2.5, p=0.02) and Angiopoietin-like 4 (FC: 2.8, p=0.01). Histologically, the amount of liver fibrosis remained unaffected, probably due to the short time of the study. Conclusions Short AAA-1 PIP induced enhanced liver steatosis and inflammation accompanied by an elevation of the expression of several pro-fibrotic genes in CDAHFD mice, suggesting that AAA-1 may contribute to the transition from MASLD to MASH. Knowing whether increased exposure time to AAA-1 could lead to end stage disease (including cirrhosis and HCC), and if this could apply to humans as well warrant further investigations.

Inhibition of ceramide de novo synthesis mitigates atherosclerosis

Abstract Background Atherosclerosis is the primary underlying cause of cardiovascular disease. Plasma ceramides are positively correlated with an increased risk of major adverse cardiovascular events and serve as an alternative biomarker for cardiovascular disease. Importantly, ceramide levels are notably higher within atherosclerotic plaques. Therefore, inhibiting the ceramide de novo synthesis pathway in the plaques may serve as a potential therapeutic intervention for atherosclerosis. Purpose We aim to assess the therapeutic efficacy of a nano-formulation of myriocin, a targeted inhibitor of serine-palmitoyl transferase, the key enzyme in ceramide de novo synthesis, in treating atherosclerosis. Methods Myriocin was encapsulated within the hydrophobic core of lipid-based nanoparticles specifically designed for this study. Male and female ApoE-/- mice, subjected to an 8-week high-fat diet regimen, received either myriocin nanoparticles (treatment group) or empty nanoparticles (control group) intravenously once a week for 4 weeks at a dose of 1.3 mg/kg body weight while still on the high-fat diet. At the study endpoint, whole aortas were harvested and subjected to Oil Red O staining to quantify the total lesion area. Histological staining was performed on serial sections of the aortic root to analyze the cellular composition within the plaques. Plasma samples were collected for total cholesterol measurement and lipidomic analysis. Results Upon intravenous administration, myriocin nanoparticles exhibited preferential accumulation in atherosclerotic plaques. Compared to control mice, those treated with myriocin nanoparticles exhibited a 58.7% reduction in total lesion area in male ApoE-/- mice and a 64.6% reduction in female ApoE-/- mice (p&amp;lt;0.0001). Consistently, the lesion areas in the aortic root were also reduced in the treated mice. Notably, myriocin nanoparticles enhanced collagen and alpha-smooth muscle content, while reducing macrophages and neutral lipids within the plaques, leading to a reduced plaque vulnerability index and preventing rupture events. TUNEL staining revealed reduced cellular apoptosis in the atherosclerotic plaques, resulting in a smaller necrotic area in the treated mice. In vitro experiments demonstrated that myriocin nanoparticles effectively inhibited lipopolysaccharide-induced inflammatory response and oxidative stress in bone marrow-derived macrophages. Furthermore, myriocin nanoparticles restored the gene expression of enzymes involved in the fatty acid beta-oxidation pathway, such as ACOX1 and CPT1A, in foam cells. Conclusion Using myriocin nanoparticles to inhibit excessive ceramide production due to inflammation reduces inflammation, and ROS production, while restoring fatty acid beta-oxidation in macrophages. This approach emerges as an effective strategy for targeting ceramide de novo synthesis within atherosclerotic plaques, thereby mitigating atherosclerosis progression and improving plaque stability.

The Role of circRNAs in the Pathological Mechanisms of Alzheimer's Disease and May Serve as Potential Biomarkers.

Alzheimer's disease (AD) is the most common neurodegenerative disease leading to dementia in the elderly, and the mechanisms of AD have not been fully defined. Circular RNAs (circRNAs), covalently closed RNAs produced by reverse splicing, have critical effects in the pathogenesis of AD. CircRNAs participate in production and clearance of Aβ and tau, regulate neuroinflammation, synaptic plasticity and the process of apoptosis and autophagy, indicating that circRNAs may be alternative biomarkers and therapeutic targets. Our review summarizes the functions of circRNAs in the progression and development of AD, which provide insights into the prospect of circRNAs in the diagnosis and treatment of AD.

Neck triangle nerve enlargement in hereditary transthyretin amyloidosis correlates with changes in the autonomic, cardiac, and gastrointestinal systems.

Hereditary transthyretin amyloidosis (ATTRv) is a hereditary disease that affects multiple bodily systems. Although sonography generally reveals enlargement of nerves in the limbs, the brachial plexus, and vagus nerve, the clinical significance of these findings remains unclear. We performed sonographic measurements of the median nerve, cervical spinal nerves at the C5-C7 level, and the vagus nerve in patients with ATTRv and healthy controls. Clinical profiles and cardiac and gastrointestinal examination results were also collected for linear regression analysis. We recruited 47 patients with ATTRv (males/females: 34/13, age: 65.6±5.3 years). The sampled segments were all significantly larger than those of the controls. In the clinical profiles, the sum of the Z scores of the neck triangle nerves (cervical spinal nerves and vagus nerve) and of all nerves (cervical spinal nerves, vagus nerve, and median nerve at the wrist) significantly correlated with the familial amyloid polyneuropathy stage, onset of autonomic nervous system (ANS) symptoms, and autonomic symptom scores. On cardiac examinations, several ultrasonography and magnetic resonance imaging parameters (primarily those that reflect heart volume) were found to be significantly correlated with the sum of the Z scores of the cervical spinal nerves but not with the Z score of the vagus nerve. In gastrointestinal evaluation, the cross-sectional area of the vagus nerve was correlated with gastric emptying time parameters on scintigraphy. Neck triangle nerve enlargement on sonography correlated with parameters related to ANS dysfunction, indicating that nerve enlargement observed on ultrasonography may serve as a potential surrogate biomarker of ATTRv.

Carotid intima-media thickness, fibroblast growth factor 23, and mineral bone disorder in children with chronic kidney disease

BackgroundCarotid intima-media thickness (cIMT) is a measure of atherosclerotic vascular disease and a surrogate biomarker for cardiovascular risk in patients with chronic kidney disease (CKD). Mineral and bone disorders (MBD) are complications of CKD, contributing to vascular calcification and accelerated atherosclerosis. Increased fibroblast growth factor 23 (FGF23)—the earliest detectable serum abnormality associated with CKD-MBD—has been linked with cardiovascular disease in patients with CKD. This study aimed to identify factors and analyze the relationship associated with high cIMT, high FGF23, and poor MBD control in children with CKD.MethodsA cross-sectional study was conducted in Yogyakarta, Indonesia recruiting children with CKD. The correlations and factors between cIMT, FGF23, and MBD were explored.ResultsWe recruited 42 children aged 2–18 years old with CKD stages 2 to 5D. There were no significant correlations between cIMT and factors including advanced CKD, use of dialysis, body mass index, hypertension, anemia, MBD, FGF23 levels, and left ventricular mass index (LVMI). Patients with advanced CKD had poorly controlled anemia, hypertension, and higher LVMI. In multivariate analysis, CKD stages, hypertension stages, the presence of MBD, and LVMI were associated with FGF23 levels (p < 0.05).ConclusionsFGF23 levels increased with CKD progression, and MBD was more prevalent in advanced kidney disease. Elevated FGF23 is potentially associated with increased MBD prevalence in late-stage CKD. A larger study is needed to confirm the factors affecting cIMT in children with CKD.

A novel DNA methylation-based surrogate biomarker for chronic systemic inflammation (InfLaMeS): results from the Health and Retirement Study.

Chronic low-grade systemic inflammation is a risk factor for chronic diseases and mortality and is an important biomarker in health research. DNA methylation (DNAm) surrogate biomarkers are valuable exposure, risk factor and health outcome predictors in studies where the measures cannot be measured directly and often perform as well or better than direct measure. We generated a DNAm surrogate biomarker for chronic, systemic inflammation from a systemic inflammation latent variable of seven inflammatory markers and evaluated its performance relative to measured inflammatory biomarkers in predicting several age-associated outcomes of interest, including mortality, activities of daily living and multimorbidity in the Health and Retirement Study (HRS). The DNAm surrogate, Inflammation Latent Variable Methylation Surrogate (InfLaMeS), correlated with seven individual inflammation markers (r= -0.2-0.6) and performed as well or better to the systemic inflammation latent variable measure when predicting multimorbidity, disability, and 4-year mortality in HRS. Findings were validated in an external cohort, The Irish Longitudinal Study of Ageing. These results suggest that InfLaMeS provides a robust alternative to measured blood-chemistry measures of inflammation with broad applicability in instances where values of inflammatory markers are not measured but DNAm data is available.

The associations of the triglyceride-glucose index and its combination with blood pressure on cardiovascular and all-cause mortality in hypertension: a national study.

The triglyceride-glucose (TyG) index, a reliable surrogate biomarker of insulin resistance (IR), is highlighted recently as related to cardiac disorders. However, the associations of the TyG index and its combination with blood pressure (BP) on cardiovascular and all-cause mortality in hypertension remain unclear. In this study, we included 9,635 hypertension patients from the National Health and Nutrition Examination Survey 1999-2018. During a median follow-up of 8.00 years, a total number of 853 and 2,489 in cardiovascular and all-cause deaths occurred, respectively. After full adjustments, the individual TyG index was positively associated with cardiovascular and all-cause mortality with J-shaped dose-response relationships. The lowest risk thresholds of the TyG index for cardiovascular and all-cause mortality were 9.5551 and 9.3405, respectively. In joint analyses, the highest risks of cardiovascular and all-cause mortality were observed among those with elevated levels of both BP and IR [1.64 (1.18, 2.28), P = 0.0031; 1.39 (1.14, 1.70), P = 0.0011; respectively]. In sensitivity and subgroup analyses, the results were generally robust. Our data appeal a hypothesis that future treatments for hypertension may require a combination of BP controlled and IR improvement.

Electrochemical aptasensor for 2-amino-2-thiazoline-4-carboxylic acid (ATCA), a metabolite for cyanide poisoning

An alternative biomarker for assessing the cyanide levels in postmortem materials is crucial for investigating acute cyanide intoxication. Herein, an aptamer–ligand biorecognition system with high specificity was developed to detect acute cyanide poisoning via its secondary metabolite, 2-amino-2-thiazoline-4-carboxylic acid (ATCA). Potential aptamers were screened from a random library of 66-base single-stranded DNA using GO-SELEX, with individual aptamers being identified through single-stranded DNA sequencing. Molecular docking was employed to predict the affinity of these aptamers toward ATCA and selected counter-targets; these predictions were confirmed using thermodynamic analysis with an isothermal titration calorimeter. Owing to its label-free biomolecular binding interactions, Apt46 exhibited the highest affinity against ATCA and notable selectivity against structurally similar counter-targets. Thus, an amino-tagged Apt46 binding aptamer was attached to a carbon electrode modified with EDC–NHS-activated graphene oxide. The binding of Apt46 to ATCA was quantified by measuring current changes using differential pulse voltammetry. The aptasensor achieved a detection limit of 0.05 µg/mL and demonstrated suitability for detecting ATCA across various biological matrices, with the high recovery percentages ranging from 92.29 to 114.22%. Overall, the proposed ATCA aptasensor is promising for identifying ATCA metabolites in cases of acute cyanide exposure.

Exploration of plasma biomarkers for Alzheimer's disease by targeted lipid metabolomics based on nuclear magnetic resonance (NMR) spectroscopy.

Alzheimer's disease (AD) is the most common cause of dementia, but the disease lacks convenient and cost-effective alternative biomarkers currently. We utilized targeted lipid metabolomics based on nuclear magnetic resonance (NMR) spectroscopy to identify plasma biomarkers in AD patients. Our study was a cross-sectional study that enrolled 58 AD patients and 40 matched health controls (HCs). Firstly, we identified plasma lipid metabolites that were significantly different between the two groups based on P < 0.05 and variable importance in the projection (VIP) > 1. Then we examined the correlation between the lipid metabolites and cognitive function using partial correlation analysis and assessed the diagnostic ability of the lipid metabolites using receiver operating characteristic (ROC) curves. Seventeen lipoproteins showed significant differences between AD patients and HCs among 114 lipid metabolites. All 17 lipoproteins were subtypes of low-density lipoprotein (LDL). Among them, LDL-3 particle number, LDL-3 apolipoprotein-B, LDL-3 phospholipids, LDL free cholesterol and LDL phospholipids were significantly correlated with cognitive function. The ROC curves showed that LDL-2 triglycerides (TG) and LDL-3 TG could significantly distinguish AD patients from HCs, with the area under the curve (AUC) above 0.7. In addition, we explored a strategy of combined diagnosis that significantly improved the diagnostic efficacy for AD (AUC = 0.879). Our study provides insight into the lipoprotein alterations associated with AD and potential biomarkers for its diagnosis and cognitive function assessment.

Using genetics to explore complement C5 as a druggable protein in periodontitis.

An excessively activated or dysregulated complement system has been proven to be a vital contributor to the pathogenesis of periodontitis. It has been previously hypothesized that inhibiting the activity of complement component C5 by targeting the C5a receptor is a powerful candidate for treating periodontitis. Here, we apply the drug target instrumental variable (IV) approach to investigate the therapeutic effect of genetically proxied inhibition of C5 on periodontitis. In our primary analysis, we used 26 independent 'cis' single nucleotide polymorphisms as IVs from the vicinity of the encoding locus of C5 that are associated with plasma C5 levels. In a secondary analysis, we assess the validity of our primary findings, exploring the involvement of alternative downstream biomarkers, interleukin 17 (IL-17), interleukin 1β (IL-1β), and tumor necrosis factor (TNF). Summary statistics of plasma levels (C5, IL-17, IL-1β, and TNF) were obtained from a genome-wide association study (GWAS) of 35,559 European descent individuals. We extracted association statistics from a GWAS of 17,353 clinical periodontitis cases and 28,210 European controls. Wald ratios were combined using inverse-variance weighted meta-analysis. In our primary approach, inhibiting C5 reduced the risk of periodontitis (Odds ratio 0.89 per 1 standard deviation reduction in C5; 95% confidence Interval 0.80-0.98, p value=0.022). Our secondary analysis suggests an involvement of IL-17 within the potential causal pathway, but was inconclusive for other biomarkers. The findings from our study suggest that C5 inhibition may reduce the risk of periodontitis, prioritizing C5 inhibitors as a potential adjunctive therapeutic intervention in this disease.