Measurement of Circulating Neuron-Specific Enolase mRNA in Diabetes Mellitus

Serum Levels of Neuron-Specific Enolase in Children With Diabetic Ketoacidosis

Neuron-specific enolase is a sensitive marker of neuronal damage in various neurologic disorders. This study aimed to measure serum neuron-specific enolase levels at different time points and severities of diabetic ketoacidosis. This study included 90 children (age 9.2 ± 3.4 years) with diabetic ketoacidosis. Neuron-specific enolase was measured at 3 time points (baseline and after 12 and 24 hours of starting treatment). Among patients, 74.4% had diagnosis of new diabetes, 60% had Glasgow Coma Scale score <15, and 75.6% had moderate/severe diabetic ketoacidosis. Compared with controls (n = 30), children with diabetic ketoacidosis had higher neuron-specific enolase levels at the 3 time points ( P = .0001). In multiple regression analysis, the factors associated with higher neuron-specific enolase levels were younger age, higher glucose, lower pH, and bicarbonate values. This study indicates that serum neuron-specific enolase is elevated in diabetic ketoacidosis and correlated with the severity of hyperglycemia, ketosis, and acidosis. This study indicates that diabetic ketoacidosis may cause neuronal injury from which the patients recovered partially but not completely.

Expression Profile of Genes Potentially Associated with Adequate Glycemic Control in Patients with Type 2 Diabetes Mellitus

Despite increasing research in type 2 diabetes mellitus (T2D), there are few studies showing the impact of the poor glycemic control on biological processes occurring in T2D. In order to identify potential genes related to poorly/well-controlled patients with T2D, our strategy of investigation included a primary screen by microarray (Human Genome U133) in a small group of individuals followed by an independent validation in a greater group using RT-qPCR. Ninety patients were divided as follows: poorly controlled T2D (G1), well-controlled T2D (G2), and normoglycemic individuals (G3). After using affy package in R, differentially expressed genes (DEGs) were prospected as candidate genes potentially relevant for the glycemic control in T2D patients. After validation by RT-qPCR, the obtained DEGs were as follows-G1 + G2 versus G3: HLA-DQA1, SOS1, and BRCA2; G2 versus G1: ENO2, VAMP2, CCND3, CEBPD, LGALS12, AGBL5, MAP2K5, and PPAP2B; G2 versus G3: HLA-DQB1, MCM4, and SEC13; and G1 versus G3: PPIC. This demonstrated a systemic exacerbation of the gene expression related to immune response in T2D patients. Moreover, genes related to lipid metabolisms and DNA replication/repair were influenced by the glycemic control. In conclusion, this study pointed out candidate genes potentially associated with adequate glycemic control in T2D patients, contributing to the knowledge of how the glycemic control could systemically influence gene expression.

Circulating Plasma Tumor DNA

Circulating cell-free DNA (ccfDNA)--first identified in 1947--is "naked" DNA that is free-floating in the blood, and derived from both normal and diseased cells. In the 1970s, scientists observed that patients with cancer had elevated levels of ccfDNA as compared to their healthy, cancer-free counterparts. The maternal fetal medicine community first developed techniques to identify the small fraction of fetal-derived ccfDNA for diagnostic purposes. Similarly, due to the presence of tumor-specific (somatic) variations in all cancers, the fraction of circulating cell-free plasma tumor DNA (ptDNA) in the larger pool of ccfDNA derived from normal cells can serve as extremely specific blood-based biomarkers for a patient's cancer. In theory this "liquid biopsy" can provide a real-time assessment of molecular tumor genotype (qualitative) and existing tumor burden (quantitative). Historically, the major limitation for ptDNA as a biomarker has been related to a low detection rate; however, current and developing techniques have improved sensitivity dramatically. In this chapter, we discuss these methods, including digital polymerase chain reaction and various approaches to tagged next-generation sequencing.

Controlled ovarian hyperstimulation induced changes in the expression of circulatory miRNA in bovine follicular fluid and blood plasma

Background

Despite its role in increasing the number of offspring during the lifetime of an individual animal, controlled ovarian hyperstimulation (COH) may have detrimental effects on oocyte development, embryo quality and endometrial receptivity. Circulating miRNAs in bio-fluids have been shown to be associated with various pathological conditions including cancers. Here we aimed to investigate the effect of COH on the level of extracellular miRNAs in bovine follicular fluid and blood plasma and elucidate their mode of circulation and potential molecular mechanisms to be affected in the reproductive tract.

Method

Twelve simmental heifers were estrous synchronized and six of them were hyperstimulated using FSH. Follicular fluid samples from experimental animals were collected using ovum pick up technique at day 0 of the estrous cycle and blood samples were collected at day 0, 3 and 7 of post ovulation. The expression profile of circulatory miRNAs in follicular fluid and blood plasma were performed using the human miRCURY LNA™ Universal RT miRNA PCR array system. A comparative threshold cycle method was used to determine the relative abundance of the miRNAs.

Results

A total of 504 and 402 miRNAs were detected in both bovine follicular fluid and blood plasma, respectively. Of these 57 and 21 miRNAs were found to be differentially expressed in follicular fluid and blood plasma, respectively derived from hyperstimulated versus unstimulated heifers. Bioinformatics analysis of those circulating miRNAs indicated that their potential target genes are involved in several pathways including TGF-beta signaling pathway, MAPK signaling pathway, pathways in cancer and Oocyte meiosis.

Moreover, detail analysis of the mode of circulation of some candidates showed that most of the miRNA were found to be detected in both exosomal and Ago2 protein complex fraction of both follicular fluid and blood plasma.

Conclusion

Our data provide the consequence of hyperstimulation induced changes of extracellular miRNAs in bovine follicular fluid and blood plasma, which may have a potential role in regulating genes associated not only with bovine ovarian function but also involved in altering various physiological in bovine oocytes, embryos and modulating reproductive tract environment.

Diabetic Stroke Severity: Epigenetic Remodeling and Neuronal, Glial, and Vascular Dysfunction

We determined the mechanism of severity during type 1 diabetic (T1D) stroke (ischemia-reperfusion [IR] injury) that affects potential markers associated with epigenetics, neuronal, glial, and vascular components of the brain with regard to nondiabetic stroke. The study used male genetic T1D Ins2(+/-) Akita and wild-type (C57BL/6J) mice. The experimental mice groups were 1) sham, 2) IR, 3) sham(Akita), and 4) IR(Akita). Mice were subjected to middle cerebral artery occlusion for 40 min, followed by reperfusion for 24 h. Brain tissues were analyzed for inflammation, neuro-glio-vascular impairments, matrix metalloproteinase (MMP)-9 expression, and epigenetic alterations (DNA methyltransferase-3a [DNMT-3a]; DNA methyltransferase-1 [DNMT-1]; 5-methylcytosine [5-mC]; and 5-hydroxymethylcytosine [5-hmC]). Intracarotid fluorescein isothiocyanate-BSA infusion was used to determine pial-venular permeability. IR(Akita) mice showed more infarct volume, edema, inflammation, and vascular MMP-9 expression compared with IR and sham groups. Sham(Akita) mice showed the highest DNMT-1 and DNMT-3a levels compared with the other groups. Reduced tight and adherent junction expressions and severe venular leakage exemplified intense cerebrovascular impairment in IR(Akita) mice compared with the other groups. Interestingly, we found differential regulations (downregulated expression) of epigenetic (5-mC, DNMTs), vascular (endothelial nitric oxide synthase), glial (connexin-43, glial fibrillary acidic protein, CD11b), and neuronal (neuron-specific enolase, neuronal nitric oxide synthase) markers in IR(Akita) compared with the IR group. These findings suggest that IR injury in T1D is more severe because it intensifies differential epigenetic markers and neuro-glio-vascular changes compared with nondiabetic mice.

Serum neuron specific enolase level as a predictor of prognosis in acute ischemic stroke patients after intravenous thrombolysis

OBJECTIVE

Serum neuron specific enolase (NSE) concentrations are significantly correlated with stroke severity and clinical outcome in ischemic stroke patients. We aimed to determine whether the serum levels of neuron specific enolase in acute ischemic stroke (AIS) patients after intravenous thrombolysis are associated with stroke severity, and indicative of favorable outcome.

METHODS

We prospectively analyzed the serum neuron specific enolase levels with for 67 subjects with AIS patients treated with intravenous recombinant tissue type plasminogen activator (rtPA) within 4.5h from symptom onset. Neurologic deficit was assessed by the National Institutes of Health Stroke Scale. Clinical outcome was assessed after 90days according to the modified Rankin Scale.

RESULTS

Neuron specific enolase levels correlated with National Institutes of Health Stroke Scale score 24h after rtPA bolus (R=0.342, p=0.005). Regarding the 67 included patients, 32 (47.8%) reached favorable outcome. They had a lower NIHSS score on admission (p=0.000) and at 24h after rtPA bolus (p=0.000), and had lower levels of neuron specific enolase (p=0.006). But only NIHSS score at 24h after rtPA bolus rather than neuron specific enolase level was an independent predictor for favorable outcome.

CONCLUSION

We found that after treatment with intravenous rtPA therapy, lower serum neuron specific enolase levels were associated with favorable outcome, which may be confounded by the link to NIHSS score.

Serum neuron-specific enolase is elevated as a novel indicator of diabetic retinopathy including macular oedema

AIM

Neuron-specific enolase as a potential biomarker of diabetic retinopathy, a neurovascular disease, had not been fully explored. We aimed to investigate the relationship between NSE and diabetic retinopathy.

METHODS

Participants included Type 1 and Type 2 diabetes patients and healthy controls (n = 392). In this cross-sectional study, diabetic retinopathy status was assessed by fundus photographs. Serum neuron-specific enolase was measured using an electrochemiluminescence immunoassay. Co-variables for diabetic retinopathy and neuron-specific enolase were obtained from fasting blood samples and interviewer questionnaires.

RESULTS

Neuron-specific enolase was slightly elevated in diabetic patients, in contrast to healthy participants, and obviously increased in diabetic patients with retinopathy compared with those without [8.3 (2.0) vs. 7.6 (1.5), P = 0.037 and 8.3 (2.0) vs. 9.5 (2.7), P = 0.004, respectively]. In addition, neuron-specific enolase levels increased with and were closely correlated to the stages of retinopathy without macular oedema [r = 0.60 (0.50-0.71), P = 0.002] and stages of macular oedema with comparable retinopathy [r = 0.58 (0.46-0.69), P = 0.006]. The association of neuron-specific enolase with diabetic retinopathy was independent [odds ration (OR): 1.31 (1.12-1.65), P = 0.017], after the diabetic state and other potential confounders affecting NSE levels were considered (e.g., HbA1c , duration, age, gender, renal status and medicines). The optimal cut-off point for serum neuron-specific enolase levels for differentiating between participants with diabetic retinopathy including macular oedema and those without was 9.3 μg/l, with a sensitivity of 67.5% and a specificity of 69.8%.

CONCLUSIONS

Serum neuron-specific enolase is elevated in and indicative of diabetic retinopathy. Neuron-specific enolase may be a potential biomarker of diabetic retinopathy. Future prospective studies are warranted to clarify the relationship.

Elevated neurofilament light chain (NFL) mRNA levels in prediabetic peripheral neuropathy

Evidence suggests that peripheral nerve injury occurs during the early stages of disease with mild glycemic dysregulation. Two proteins, neuron-specific enolase (NSE) and neurofilament light chain (NFL), have been examined previously as possible markers of neuronal damage in the pathophysiology of neuropathies. Herein, we aimed to determine the potential value of circulatory NSE and NFL mRNA levels in prediabetic patients and in those with peripheral neuropathy. This prospective clinical study included 45 prediabetic patients and 30 age- and sex-matched controls. All prediabetic patients were assessed with respect to diabetes-related microvascular complications, such as peripheral neuropathy, retinopathy and nephropathy. mRNA levels of NSE and NFL were determined in the blood by real-time polymerase chain reaction. NSE mRNA levels were similar between prediabetic and control groups (p > 0.05), whereas NFL mRNA levels were significantly higher in prediabetics than in controls (p < 0.001). NSE mRNA levels did not significantly differ between prediabetic patients with and without peripheral neuropathy (p > 0.05), while NFL mRNA levels were significantly higher in prediabetics with peripheral neuropathy than in those without (p = 0.038). According to correlation analysis, NFL mRNA levels were positively correlated with the Douleur Neuropathique 4 questionnaire score in prediabetic patients (r = 0.302, p = 0.044). This is the first study to suggest blood NFL mRNA as a surrogate marker for early prediction of prediabetic peripheral neuropathy, while NSE mRNA levels may be of no diagnostic value in prediabetic patients.

NSE, a potential biomarker, is closely connected to diabetic peripheral neuropathy

OBJECTIVE

To explore the relationship between serum neuron-specific enolase (NSE) levels and diabetic neuropathy.

RESEARCH DESIGN AND METHODS

Type 1 or 2 diabetic and healthy control subjects (n = 568) were randomly enrolled in a cross-sectional study. Diabetic neuropathy status was documented by the presence of clinical symptoms or signs, electromyography, quantitative sensory tests, and cardiac autonomic neuropathy tests. The severity of the neuropathy was staged by composite scores. Serum NSE was measured using electrochemiluminescence immunoassay. The demographic and clinical variables were obtained through an interviewer questionnaire.

RESULTS

Serum NSE levels increased slightly in diabetic subjects compared with normal subjects (9.1 [1.5] vs. 8.7 [1.7], P = 0.037), and the levels increased greatly in diabetic subjects with neuropathy compared with those without (10.8 [2.8] vs. 9.1 [1.5], P = 0.000). The association of NSE with diabetic neuropathy was independent of the hyperglycemic state (fasting blood glucose, HbA1c, duration, and the type of diabetes) and other potential confounders affecting NSE levels (e.g., age, sex, and renal status) (odds ratio 1.48 [1.13-1.74], P = 0.001). In addition, NSE levels increased with and were closely correlated to the stages of neuropathy (r = 0.63 [0.52-0.74], P = 0.000). The optimal cutoff point for serum NSE levels to distinguish patients with diabetic neuropathy from those without was 10.10 μg/L, with a sensitivity of 66.3% and a specificity of 72.5%.

CONCLUSIONS

Serum NSE levels are closely associated with peripheral neuropathy in patients with diabetes. Future studies are warranted to clarify the relationship.

Prognostic value of neuron specific enolase and IL-10 in ischemic stroke and its correlation with degree of neurological deficit

BACKGROUND

The blood-brain barrier is compromised in stroke patients. The release of neuro-biochemical protein markers, such as Neuron Specific Enolase (NSE) into the circulation may allow the pathophysiology and prognosis of patients with cerebrovascular diseases to be evaluated further.

METHOD

Present study aimed to investigate the predictive value of NSE and Interleukin-10 (IL-10) with respect to early neurobehavioral outcome which evaluated by National Institute of Health Stroke Scale (NIHSS). We investigated 100 patients of ischemic stroke and blood samples were taken within first 72 h of stroke onset. NSE and IL-10 were analyzed by commercially available ELISA kits. The neurological status was evaluated by a standardized NIHSS at the time of admission.

RESULTS

NSE was significantly increased (17.95±4.54 vs 7.48±1.51 {ng/ml} p≤0.05) and IL-10 significantly decreased (11.79±2.77 vs 15.72±2.69 {pg/ml} p≤0.05) in patients when compared with controls. NSE also significantly (r=0.8, p≤0.001) correlated with degree of neurological deficit but IL-10 level in serum did not show any significant correlation with NIHSS score at the time of admission.

CONCLUSIONS

Serum concentrations of NSE and IL-10 have a high predictive value for early neurobehavioral outcome after acute stroke.

Recovering circulating extracellular or cell-free RNA from bodily fluids

The presence of extracellular circulating or cell-free RNA in biological fluids is becoming a promising diagnostic tool for non invasive and cost effective cancer detection. Extracellular RNA or miRNA as biological marker could be used either for the early detection and diagnosis of the disease or as a marker of recurrence patterns and surveillance. In this review article, we refer to the origin of the circulating extracellular RNA, we summarise the data on the biological fluids (serum/plasma, saliva, urine, cerebrospinal fluid and bronchial lavage fluid) of patients suffering from various types of malignancies reported to contain a substantial amount of circulating extracellular (or cell-free) RNAs and we discuss the appropriate reagents and methodologies needed to be employed in order to obtain RNA material of high quality and integrity for the majority of the experimental methods used in RNA expression analysis. Furthermore, we discuss the advantages and disadvantages of the RT-PCR or microarray methodology which are the methods more often employed in procedures of extracellular RNA analysis.

Transforming growth factor beta 1 as a biomarker of diabetic peripheral neuropathy: cross-sectional study

BACKGROUND

Simple and efficient screening methods are lacking for diabetic peripheral neuropathy (DPN), the most common and most difficult to treat of the long-term diabetic complications. Increased levels of transforming growth factor beta 1 (TGFbeta1) in type 2 diabetic patients (T2DM) plays an immunomodulatory role in diabetic nephropathy and, possibly, in atherosclerotic evolution. Since preliminary interrelationships between experimental DPN and TGFbeta1 have been observed, we sought to assess whether TGFbeta1 could be a biomarker molecule for human DPN.

MATERIALS AND METHODS

Cross-sectional cohort study focused on the assessment of the interrelationships between TGFbeta1 levels, cardiovascular disease (CVD), diabetic nephropathy (DNF), and neuropathy (DPN) in a group of T2DM patients (N=180; male 117, female 63) randomly selected from the North Catalonia Diabetes Study. DPN was diagnosed using clinical and neurophysiology evaluation. Incipient DNF was assessed by microalbuminuria (MAU). Total TGFbeta1 (without acidification) was measured by immunoassay by ELISA (Promega).

RESULTS

DPN correlated with age, time of diabetes duration, MAU, CVD, and TGFbeta1 (P<.0001). Log-transformed TGFbeta1 (logTGbeta1) was significantly higher in patients with DPN than in those without (P<.0005). LogTGFbeta1 (OR=7.5; P=.006), age (OR=1.1; P<.0005), and logMAU (OR=2.0; P=.016) appear as significant estimators of the occurrence of DPN in our series. The integrated ROC curve evaluation with these three parameters expressed an important sensitivity (78.1%), specificity (76.0%), positive predictive value (79.2%), and negative predictive value (70.3%) in relation to DPN presence.

DISCUSSION

TGFbeta1 stands as an important biomarker molecule for DFN and DPN screening in our series. Further prospective studies are warranted.

Quantitative analyses and transcriptomic profiling of circulating messenger RNAs as biomarkers of rat liver injury

Serum aminotransferases have been the clinical standard for evaluating liver injury for the past 50-60 years. These tissue enzymes lack specificity, also tracking injury to other tissues. New technologies assessing tissue-specific messenger RNA (mRNA) release into blood should provide greater specificity and permit indirect assessment of gene expression status of injured tissue. To evaluate the potential of circulating mRNAs as biomarkers of liver injury, rats were treated either with hepatotoxic doses of D-(+)-galactosamine (DGAL) or acetaminophen (APAP) or a myotoxic dose of bupivacaine HCl (BPVC). Plasma, serum, and liver samples were obtained from each rat. Serum alanine aminotransferase and aspartate aminotransferase were increased by all three compounds, whereas circulating liver-specific mRNAs were only increased by the hepatotoxicants. With APAP, liver-specific mRNAs were significantly increased in plasma at doses that had no effect on serum aminotransferases or liver histopathology. Characterization of the circulating mRNAs by sucrose density gradient centrifugation revealed that the liver-specific mRNAs were associated with both necrotic debris and microvesicles. DGAL treatment also induced a shift in the size of plasma microvesicles, consistent with active release of microvesicles following liver injury. Finally, gene expression microarray analysis of the plasma following DGAL and APAP treatment revealed chemical-specific profiles.

CONCLUSION

The comparative analysis of circulating liver mRNAs with traditional serum transaminases and histopathology indicated that the circulating liver mRNAs were more specific and more sensitive biomarkers of liver injury. Further, the possibility of identifying chemical-specific transcriptional profiles from circulating mRNAs could open a range of possibilities for identifying the etiology of drug/chemical-induced liver injury.