Accuracy of Two Continuous Glucose Monitoring Devices During Aerobic and High-Intensity Interval Training in Individuals with Type 1 Diabetes

BBACKGROUND

This study aimed to evaluate the accuracy of Dexcom G6 (DG6) and FreeStyle Libre-2 (FSL2) during aerobic training and HIIT in individuals with type 1 diabetes (T1D).

METHODS

Twenty-six males (mean age 29.3 ± 6.3 years and mean duration of diabetes 14.9 ± 6.1 years) participated in this study. Interstitial glucose levels were measured using DG6 and FSL2, while plasma glucose levels were measured every 10 min using YSI 2500 as the reference for glucose measurements in this study. The measurements began 20 min before the start of exercise and continued for 20 min after exercise. Seven measurements were taken for each subject and exercise.

RESULTS

Both DG6 and FSL2 devices showed significant differences compared to YSI glucose data for both aerobic and HIIT exercises. Continuous glucose monitoring (CGM) devices exhibited superior performance during HIIT than aerobic training, with DG6 showing a mean absolute relative difference (MARD) of 14.03% versus 31.98%, respectively. In the comparison between the two devices, FSL2 demonstrated significantly higher effectiveness in aerobic training, yet its performance was inferior to DG6 during HIIT. According to the 40/40 criteria, both sensors performed similarly, with marks over 93% for all ranges and both exercises, and above 99% for HIIT and in the >180 mg/dL range, which is in accordance with FDA guidelines.

CONCLUSIONS

The findings suggest that the accuracy of DG6 and FSL2 deteriorates during and immediately after exercise, but remains acceptable for both devices during HIIT. However, accuracy is compromised with DG6 during aerobic exercise. This study is the first to compare the accuracy of two CGMs, DG6 and FSL2, during two exercise modalities, using plasma glucose YSI measurements as the gold standard for comparisons.

Association of carotid atheroma plaque with IL-18 levels and with polymorphisms in the IL-18 receptor gene in a Mediterranean population

BACKGROUND

Atherosclerosis is an inflammatory disease. Interleukin 18 (IL-18) is an inflammatory molecule that has been linked to the development of atherosclerosis and cardiovascular disease.

OBJECTIVE

To evaluate the possible relationship between plasma levels of IL-18 and the presence of atherosclerosis evaluated at the carotid level, as well as to analyze the possible modulation by different polymorphisms in a Mediterranean population.

MATERIAL AND METHODS

Seven hundred and forty-six individuals from the metropolitan area of Valencia were included, recruited over a period of 2 years. Hydrocarbon and lipid metabolism parameters were determined using standard methodology and IL-18 using ELISA. In addition, carotid ultrasound was performed and the genotype of four SNPs related to the IL-18 signaling pathway was analyzed.

RESULTS

Patients with higher plasma levels of IL-18 had other associated cardiovascular risk factors. Elevated IL-18 levels were significantly associated with higher carotid IMT and the presence of atheromatous plaques. The genotype with the A allele of the SNP rs2287037 was associated with a higher prevalence of carotid atheromatous plaque. On the contrary, the genotype with the C allele of the SNP rs2293224 was associated with a lower prevalence of atheromatous plaque.

CONCLUSIONS

High levels of IL-18 were significantly associated with a higher carotid IMT and the presence of atheromatous plaques, which appear to be influenced by genetic factors, as evidenced by associations between SNPs in the IL-18 receptor gene and the presence of atheroma plaque.

Fibroblast-derived extracellular vesicles as trackable efficient transporters of an experimental nanodrug with fibrotic heart and lung targeting

The discovery of extracellular vesicles (EVs) as efficient exogenous biotransporters of therapeutic agents into cells across biological membranes is an exciting emerging field. Especially the potential of EVs as targeted delivery systems for diseases with selective treatments, such as fibrosis, whose treatment causes side effects in other organs not involved in the disease. Methods: In this study, we collected embryonic fibroblast-derived EVs from two different centrifugation fractions, 10 K g and 100 K g fractions from a NIH-3T3 cell line loaded with an experimental drug. Mice with fibrotic hearts and lungs were obtained by administration of angiotensin II. We generated fluorescent EVs and bioluminescent drug to observe their accumulation by colocalization of their signals in fibrotic heart and lung. The biodistribution of the drug in various organs was obtained by detecting the Au present in the drug nanostructure. Results: The drug-loaded EVs successfully reduced fibrosis in pathological fibroblasts in vitro, and modified the biodistribution of the experimental drug, enabling it to reach the target organs in vivo. We described the pre-analytical characteristics of EVs related to physical variables, culture and harvesting conditions, crucial for their in vivo application as nanotransporters using a previously validated protein-based antifibrotic drug. The results showed the colocalization of EVs and the experimental drug in vivo and ex vivo and the efficient reduction of fibrosis in vitro. This work demonstrates that 10K-EVs and 100K-EVs derived from fibroblasts can act as effective biotransporters for targeted drug delivery to profibrotic fibroblasts, lungs, or heart. Conclusion: We observed that fibroblast-derived 10K-EVs and 100K-EVs are useful biotransporters encapsulating a new generation drug leading to a reduction of fibrosis in profibrotic fibroblasts in vitro. In addition, drug containing EVs were shown to reach fibrotic heart and lungs in vivo, enhancing free drug biodistribution.

Comparison of GLP-1 receptor agonists and other Glucose-Lowering agents on cardiovascular outcomes in individuals with type 2 diabetes and Obesity: A Spanish Real-World Population-Based study

AIMS

Assess the impact of glucagon-like peptide receptor agonists (GLP-1RA) compared to other glucose-lowering agents on cardiovascular outcomes in individuals with type 2 diabetes and obesity in a Spanish metropolitan area.

METHODS

A retrospective population-based type 2 diabetes cohort was identified from the Valencia Clinic-Malvarrosa Department electronic databases (2014-2019). Study groups included GLP-1RA, sodium-glucose co-transporter-2 inhibitors (SGLT2i), Insulin, and Miscellany (other glucose-lowering agents). 1:1:1:1 propensity score matching was conducted. The primary outcome was a composite of major adverse cardiovascular events (4-point MACE) comprising myocardial infarction, stroke, all-cause mortality, and heart failure. Secondary outcomes included individual 4-point MACE components. Hazard ratios were estimated using Cox regression analyses against the Miscellany group.

RESULTS

From 26,944 subjects, 1,848 adults were selected per group. GLP-1RA did not show a significant reduction in 4-point MACE risk (HR 1.05 [95%CI 0.82-1.34]). SGLT2i significantly reduced the risk of heart failure (HR 0.16 [95%CI 0.05-0.54]) and atrial fibrillation (HR 0.58, [95%CI 0.35-0.95]). The Insulin group exhibited a higher risk for 4-point MACE and most individual outcomes compared to GLP-1RA and SGLT2i.

CONCLUSIONS

Our findings do not provide evidence of a reduced cardiovascular risk, as assessed by 4-point MACE, with GLP-1RA. In contrast, SGLT2i demonstrated protective effects against heart failure and atrial fibrillation.

Estimating Quadriceps and Hamstrings Strength Through Myoton Among Recreational Athletes

CONTEXT

The assessment of strength is one of the most usual practices among professionals involved in health care or sport. Quadriceps and hamstrings are the most commonly assessed muscle groups. Generally, the methods used to assess muscle strength are active and, therefore, alternative passive methods could be useful. Myoton provides measures on 3 mechanical properties of the muscle: tone, elasticity, and stiffness.

OBJECTIVE

This study aimed to analyze the association of Myoton, an easy-to-use tool not requiring voluntary stimulus from the subject, with strength values in quadriceps and hamstrings.

STUDY DESIGN

Experimental.

SETTING

University kinesiology laboratory.

PARTICIPANTS

Thirty-eight recreational athletes were evaluated.

MAIN OUTCOME MEASURES

Anthropometric and demographic data, Myoton-based measures of vastus lateralis, rectus femoris, vastus medialis, biceps femoris, and semitendinosus, and the maximum voluntary isometric contraction of quadriceps and hamstrings.

PROCEDURES

The association was examined using multiple regression models to estimate strength through Myoton-based parameters and different patient characteristics. The models encompassed either 2 or 3 independent variables.

RESULTS

The adjusted R2 values for predicting quadriceps strength were .666 for rectus femoris, .726 for vastus lateralis, and .667 for vastus medialis, while in regard to hamstrings, they were .617 for biceps femoris and .604 for semitendinosus.

CONCLUSIONS

The main finding was that acceptable relationships were found between muscle strength and Myoton-based parameters when variables such as gender and/or age are considered. Our study reveals a new tool for estimating strength with outstanding advantages: it is easy, time-efficient, adaptable, and highly manageable through the feasible equations provided.

Systematic analysis of YFP traps reveals common mRNA/protein discordance in neural tissues

While post-transcriptional control is thought to be required at the periphery of neurons and glia, its extent is unclear. Here, we investigate systematically the spatial distribution and expression of mRNA at single molecule sensitivity and their corresponding proteins of 200 YFP trap lines across the intact Drosophila nervous system. 97.5% of the genes studied showed discordance between the distribution of mRNA and the proteins they encode in at least one region of the nervous system. These data suggest that post-transcriptional regulation is very common, helping to explain the complexity of the nervous system. We also discovered that 68.5% of these genes have transcripts present at the periphery of neurons, with 9.5% at the glial periphery. Peripheral transcripts include many potential new regulators of neurons, glia, and their interactions. Our approach is applicable to most genes and tissues and includes powerful novel data annotation and visualization tools for post-transcriptional regulation.

Real-World Evaluation of GLP-1 Receptor Agonist Therapy Persistence, Adherence and Therapeutic Inertia Among Obese Adults with Type 2 Diabetes

INTRODUCTION

In type 2 diabetes (T2D), key barriers to optimal glycaemic control include lack of persistence with treatment, reduced medication adherence and therapeutic inertia. This study aimed to assess the impact of these barriers in obese adults with type 2 diabetes treated with a GLP-1 receptor agonist (GLP-1RA) and compare them against other glucose-lowering agents in a real-world setting.

METHODS

A retrospective study was conducted using electronic medical records from 2014 to 2019 for adults with T2D at the Valencia Clínico-Malvarrosa Department of Health (Valencia, Spain). Four study groups were established: all GLP-1RA users, SGLT2i users, insulin users and other glucose-lowering agent users (miscellany group). To account for imbalance between groups, propensity score matching (PSM) including age, gender and pre-existing cardiovascular disease was performed. Chi-square tests were used for comparisons between groups. Time to first intensification was calculated using competing risk analysis.

RESULTS

Among the 26,944 adults with T2D, 7392 individuals were selected following PSM, with 1848 patients in each group. At 2 years, GLP-1RA users were less persistent than non-users (48.4% versus 72.7%, p < 0.0001) but more adherent (73.8% versus 68.9%, respectively, p < 0.0001). A greater proportion of persistent GLP-1RA users than non-persistent users exhibited reduced HbA1c (40.5% versus 18.6%, respectively, p < 0.0001), but no differences in cardiovascular outcomes and death were found. Overall, therapeutic inertia was observed in 38.0% of the study population. The large majority of GLP-1RA users received treatment intensification, whereas only 50.0% of GLP-1RA non-users were intensified.

CONCLUSION

Under real-life conditions, obese adults with T2D persistently treated with GLP-1RA showed improved glycaemic control. Despite benefits, persistence with GLP-1RA was limited after 2 years. Additionally, therapeutic inertia occurred in two out of three study participants. Strategies to facilitate medication adherence, persistence and treatment intensification in people with T2D should be made a priority in order to achieve and maintain glycaemic targets and improve outcomes in this population.

TRAIL REGISTRATION

Study registered in clinicaltrials.org with the identifier NCT05535322.

Profibrotic Role of Inducible Heat Shock Protein 90α Isoform in Systemic Sclerosis

Systemic sclerosis (SSc) is an autoimmune disease that affects skin and multiple internal organs. TGF-β, a central trigger of cutaneous fibrosis, activates fibroblasts with the involvement of the stress-inducible chaperone heat shock protein 90 isoform α (Hsp90α). Available evidence supports overexpression and secretion of Hsp90α as a feature in profibrotic pathological conditions. The aim of this work is to investigate the expression and function of Hsp90α in experimental models of skin fibrosis such as human fibroblasts, C57BL/6 mice, and in human SSc. For this purpose, we generated a new experimental model based on doxorubicin administration with improved characteristics with respect to the bleomycin model. We visualized disease progression in vivo by fluorescence imaging. In this work, we obtained Hsp90α mRNA overexpression in human skin fibroblasts, in bleomycin- and doxorubicin-induced mouse fibrotic skin, and in lungs of bleomycin- and doxorubicin-treated mice. Hsp90α-deficient mice showed significantly decreased skin thickness compared with wild-type mice in both animal models. In SSc patients, serum Hsp90α levels were increased in patients with lung involvement and in patients with the diffuse form of SSc (dSSc) compared with patients with the limited form of SSc. The serum Hsp90α levels of patients dSSc were correlated with the Rodnan score and the forced vital capacity variable. These results provide new supportive evidence of the contribution of the Hsp90α isoform in the development of skin fibrosis. In SSc, these results indicated that higher serum levels were associated with dSSc and lung fibrosis.

The Controversial Role of Vitamin D in Thyroid Cancer Prevention

Thyroid cancer is the most common endocrine malignancy and exhibits rising incidence. Annual incidence varies by sex, age, and geographical location. It has been reported that impairment of vitamin D signalling promotes thyroid cancer progression. Recent studies have shown that vitamin D, a fat-soluble vitamin that acts as both a nutrient and a hormone, may have utility in the prevention of autoimmune thyroid-related diseases. However, the precise role of vitamin D in the pathobiology of thyroid cancer is controversial. Previous studies have suggested that elevated serum vitamin D levels have a protective role in thyroid cancer. However, there is also evidence demonstrating no inverse relationship between vitamin D levels and the occurrence of thyroid cancer. Furthermore, recent data provide evidence that circulating vitamin D concentration is inversely correlated with disease aggressiveness and poor prognosis, while evidence of an association with tumour initiation remains weak. Nevertheless, a variety of data support an anti-tumorigenic role of vitamin D and its potential utility as a secondary chemopreventive agent. In this review, we highlighted recent findings regarding the association of vitamin D status with the risk of thyroid cancer, prognosis, potential mechanisms, and possible utility as a chemopreventive agent.

Impact of COVID-19 lockdown on diabetes management and follow-up in a broad population in Spain

BACKGROUND

To evaluate the impact of COVID-19 lockdown on glycaemic control and diabetes follow-up in a Spanish metropolitan area with a total general population of 340,000.

METHODS

A retrospective real-world study comparing HbA1c testing, an indicator of diabetes control, and mean HbA1c during different COVID-19 restriction periods in 2020 (full lockdown, post-lockdown, partial lockdown) with the same periods in 2019. HbA1c testing was analysed per study period and according to gender, age and clinical setting. Associations between HbA1c testing and different covariables were investigated using logistic regression analysis. Changes in HbA1c were evaluated by repeated measures multivariate analysis of variance (ANOVA).

RESULTS

During full lockdown, 6847 individuals, of which 56.7% were over 65 and 6.5% below 40, were tested for HbA1c compared to 14,180 in 2019 (OR 0.47, 95% CI:0.46-0.49). Reduction in HbA1c testing was greater among older individuals (OR 0.44, 95% CI:0.42-0.45). No differences were observed for post-lockdown (OR 1.01, 95% CI:0.99-1.04). During partial lockdown, 10,816 individuals had at least one HbA1c measured compared to 12,749 in 2019 (OR 0.84, 95% CI:0.82-0.87). Mean HbA1c during full lockdown was 7.26% (±1.06) compared to 7.50% (±1.14) in 2019 (p < .0001). For gender and across all age groups, HbA1c levels were lower during full lockdown. HbA1c changes were not significantly different during post-lockdown and partial lockdown.

CONCLUSIONS

COVID-19 restriction measures affected HbA1c testing. During complete lockdown, HbA1c testing decreased by half across all gender and age groups. No deleterious effect on glycaemic control was observed during lockdown and post-lockdown among those tested.

Real-world Evidence of Efficacy and Safety of SGLT2 Inhibitors as Adjunctive Therapy in Adults With Type 1 Diabetes: A European Two-Center Experience

OBJECTIVE

To evaluate real-world efficacy and safety of sodium-glucose cotransporter 2 inhibitor (SGLT2i) use in combination with insulin in people with type 1 diabetes.

RESEARCH DESIGN AND METHODS

We conducted a retrospective cohort European two-center study. Data on demographics, HbA1c, weight, insulin use, renal function, and adverse events were collected for 199 adults with type 1 diabetes who initiated a SGLT2i adjunct to insulin. Subgroup analyses were performed to identify who benefited most and who was more at risk for adverse events.

RESULTS

Overall, significant reductions in mean HbA1c (-0.5%), weight (-2.9 kg), and daily insulin (-8.5%) were achieved after 12 months. The greatest reduction in HbA1c was obtained in individuals with baseline HbA1c >8% (-0.7% [64 mmol/mol]). The most weight loss was observed in subjects with BMI >27 kg/m2 (-3.5 kg). Individuals with baseline estimated glomerular filtration rate (eGFR) <90 mL/min/1.73 m2 showed an increase in eGFR (4.5 mL/min/1.73 m2), whereas those with urinary albumin-to-creatinine ratio (UACR) >15 mg/g showed a decrease in UACR (-16.6 mg/g). Fifty-seven individuals (28.6%) reported adverse events: 45 with genital infections (22.6%), 5 ketosis episodes (2.5%), and 7 diabetic ketoacidosis (DKA) (3.5%). No severe hypoglycemia events were reported.

CONCLUSIONS

Our real-world data on SGLT2i showed promising results in reductions in HbA1c, weight, and insulin requirements in type 1 diabetes. Benefits were more pronounced in individuals with higher baseline HbA1c and BMI. DKA remained a major concern, despite educational measures. Further real-life evidence is still required for evaluation of SGLT2i longer-term effects and their impact on reno-cardiovascular outcomes.

Correlative 3D cryo X-ray imaging reveals intracellular location and effect of designed antifibrotic protein-nanomaterial hybrids

Revealing the intracellular location of novel therapeutic agents is paramount for the understanding of their effect at the cell ultrastructure level. Here, we apply a novel correlative cryo 3D imaging approach to determine the intracellular fate of a designed protein–nanomaterial hybrid with antifibrotic properties that shows great promise in mitigating myocardial fibrosis. Cryo 3D structured illumination microscopy (cryo-3D-SIM) pinpoints the location and cryo soft X-ray tomography (cryo-SXT) reveals the ultrastructural environment and subcellular localization of this nanomaterial with spatial correlation accuracy down to 70 nm in whole cells. This novel high resolution 3D cryo correlative approach unambiguously locates the nanomaterial after overnight treatment within multivesicular bodies which have been associated with endosomal trafficking events by confocal microscopy. Moreover, this approach allows assessing the cellular response towards the treatment by evaluating the morphological changes induced. This is especially relevant for the future usage of nanoformulations in clinical practices. This correlative super-resolution and X-ray imaging strategy joins high specificity, by the use of fluorescence, with high spatial resolution at 30 nm (half pitch) provided by cryo-SXT in whole cells, without the need of staining or fixation, and can be of particular benefit to locate specific molecules in the native cellular environment in bio-nanomedicine.

A novel 3D cryo correlative approach locates designed therapeutic protein–nanomaterial hybrids in whole cells with high specificity and resolution. Detection of treatment-induced morphological changes, crucial for pre-clinical studies, are revealed.

Peripheral blood levels of CXCL10 are a useful marker for diabetic polyneuropathy in subjects with type 2 diabetes

BACKGROUND

Diabetic peripheral neuropathy (DPN) is a chronic complication of diabetes mellitus associated with high morbidity and mortality. Major risk factors for DPN include metabolic changes, duration of diabetes, nerve ischaemia and derangements in regeneration and nerve repair programmes. Chemokines have been previously implicated in the pathogenesis of various neuropathies and neuropathic pain processes. The aim of this pilot study was to evaluate the association between the plasma levels of chemokines (CXCL9, CXCL10 and CXCL11) in the presence of DPN in a cohort of type 2 diabetes (T2D) patients.

MATERIALS AND METHODS

We studied 73 patients with T2D: 36 with DPN and 37 without DPN. DPN was established through the Semmes-Weinstein test (SW). Plasma levels of circulating chemokines CXCL9, CXCL10 and CXCL11 were determined using DuoSet ELISA kits (Abingdon, UK).

RESULTS

We found that levels of CXCL10 were significantly higher in patients with DPN than amongst patients without DPN (57.6 ± 38.3 vs 38.1 ± 33.4 pg/mL, respectively; P = .034). Serum levels of chemokine CXCL9 were also higher amongst patients with DPN but did not reach a statistical significance (188.1 ± 72.7 and 150.4 ± 83.6 pg/mL, respectively, P = .06).

CONCLUSIONS

Increased circulating levels of CXCL10 were associated with DPN in T2D patients, suggesting a role of this chemokine in the DPN. Determination of CXCL10 levels could be used as a marker for the early detection and implementation of therapeutic strategies in order to reverse and prevent the DPN.

Epigenetic alterations of TGFβ and its main canonical signaling mediators in the context of cardiac fibrosis

Cardiac fibrosis is a pathological process that presents a continuous overproduction of extracellular matrix (ECM) components in the myocardium, which negatively influences the progression of many cardiac diseases. Transforming growth factor β (TGFβ) is the main ligand that triggers the production of pro-fibrotic ECM proteins. In the cardiac fibrotic process, TGFβ and its canonical signaling mediators are tightly regulated at different levels as well as epigenetically. Cardiac fibroblasts are one of the most important TGFβ target cells activated after cardiac injury. TGFβ-driven fibroblast activation is subject to epigenetic modulation and contributes to the progression of cardiac fibrosis, mainly through the expression of pro-fibrotic molecules implicated in the disease. In this review, we describe epigenetic regulation related to canonical TGFβ signaling in cardiac fibroblasts.

Therapeutic inertia in patients with type 2 diabetes treated with non-insulin agents

AIMS

To analyze therapeutic inertia in type 2 diabetes (T2D) subjects with suboptimal glycemic control and treated with ≥2 non-insulin antidiabetic agents in a primary care setting.

METHODS

A retrospective study was conducted using electronic medical records from subjects with HbA1c ≥7.0% (≥53 mmol/mol). Therapeutic inertia was defined as the absence of treatment intensification despite suboptimal glycemic control where intensification should have been implemented (HbA1c ≥7.5% [≥58 mmol/mol]). Time to the first intensification with non-insulin antidiabetic agent or insulin and HbA1c values at the time of intensification were evaluated by competing risk analysis.

RESULTS

2652 adults with T2D and HbA1c ≥7.0% (≥53 mmol/mol) were included. During the 4-year follow-up, among 1628 individuals with HbA1c ≥7.5% [≥58 mmol/mol], therapeutic inertia was present in 42.9% of cases. Median time to intensification was 14.5 months (IQR_25-75, 4-24 months). In this subgroup, 72.7% of subjects initiated non-insulin agents whereas 27.3% initiated insulin. Mean HbA1c values at initiation of treatment intensification were 8.6% (70 mmol/mol) and 9.2% (77 mmol/mol), respectively.

CONCLUSIONS

Therapeutic inertia occurred in over 40% of subjects. Treatment intensification took longer and was performed at higher HbA1c than recommended in clinical guidelines. Reducing therapeutic inertia is a priority to achieve therapeutic goals and prevent chronic complications in T2D.

CryoSIM: super-resolution 3D structured illumination cryogenic fluorescence microscopy for correlated ultrastructural imaging

Rapid cryopreservation of biological specimens is the gold standard for visualizing cellular structures in their true structural context. However, current commercial cryo-fluorescence microscopes are limited to low resolutions. To fill this gap, we have developed cryoSIM, a microscope for 3D super-resolution fluorescence cryo-imaging for correlation with cryo-electron microscopy or cryo-soft X-ray tomography. We provide the full instructions for replicating the instrument mostly from off-the-shelf components and accessible, user-friendly, open-source Python control software. Therefore, cryoSIM democratizes the ability to detect molecules using super-resolution fluorescence imaging of cryopreserved specimens for correlation with their cellular ultrastructure.

Subclinical atherosclerosis burden predicts cardiovascular events in individuals with diabetes and chronic kidney disease

Background

Individuals with diabetes have remarkably high rates of cardiovascular morbidity and mortality. However, the incremental cardiovascular risk in diabetes is heterogeneous and has often been related to renal involvement. The purpose of this study was to analyse the prognostic value of subclinical atherosclerosis in determining the incidence of first cardiovascular events (CVEs) in individuals with diabetes and chronic kidney disease (CKD) compared to CKD individuals without diabetes.

Methods

We included data from individuals with CKD with and without diabetes, free from pre-existing cardiovascular disease, from the NEFRONA cohort. Participants underwent baseline carotid and femoral ultrasound and were followed up for 4 years. All CVEs during follow-up were registered. Bivariate analysis and Fine–Gray competing risk models were used to perform the statistical analysis.

Results

During the mean follow-up time of 48 months, a total of 203 CVE was registered. 107 CVE occurred among participants without diabetes (19.58 per 1000 person-years) and 96 CVE occurred among participants with diabetes (44.44 per 1000 person-years). Following the competing risk analysis, the variables predicting CVEs in CKD individuals without diabetes were the number of territories with plaque at baseline (HR 1.862, 95% CI [1.432;2.240]), age (HR 1.026, 95% CI [1.003;1.049]) and serum concentrations of 25-OH vitamin D (HR 0.963, 95% CI [0.933;0.094]). The only variable predicting CVEs among CKD participants with diabetes was the number of territories with plaque at baseline (HR 1.782, 95% CI [1.393, 2.278]). For both models, concordance (C) index yielded was over 0.7.

Conclusions

The burden of subclinical atherosclerosis is the strongest predictor of future CVEs in diabetic individuals with CKD. Early detection of subclinical atherosclerotic burden by multiterritorial vascular ultrasound could improve CVE prediction in this population.

Electronic supplementary material

The online version of this article (10.1186/s12933-019-0897-y) contains supplementary material, which is available to authorized users.

Prevalence and progression of subclinical atherosclerosis in patients with chronic kidney disease and diabetes

BACKGROUND AND AIMS

Cardiovascular disease is the leading cause of morbidity and mortality in patients with chronic kidney disease (CKD) and diabetes. Traditional cardiovascular risk factors fail to fully account for the increase in cardiovascular risk in these patients. This study aims to analyse the prevalence and progression of subclinical atherosclerosis in CKD patients with and without diabetes.

METHODS

We included data from CKD patients with and without diabetes free from previous cardiovascular events from the NEFRONA cohort. Patients underwent baseline and 24-month follow-up carotid and femoral ultrasound examinations. Multivariable models were used to assess the contribution of diabetes to the presence and plaque progression.

RESULTS

A total of 419 patients with diabetes and 1129 without diabetes were included. Diabetic patients were older, had higher BMIs, more hypertension and dyslipidaemia. At baseline, the proportion of patients with plaque was higher among diabetic patients (81.4% vs. 64.1%, p < 0.001). Diabetic patients more frequently had more than two vascular territories with plaque (64.4% vs. 48.4%, p < 0.001). Multivariable analysis indicated that plaque at baseline was significantly associated with age, gender, smoking and renal replacement therapy (RRT) in the non-diabetic patients, but only with age and male gender in diabetic patients. Plaque progression was significantly associated with age, number of territories with basal plaque, smoking and RRT in both groups.

CONCLUSIONS

Subclinical atherosclerosis is more prevalent, carries a higher plaque burden and is more rapidly progressive in renal patients with diabetes. In these patients, diabetes outweighs other described risk factors associated with the presence of subclinical atherosclerosis.

Super-Resolution Single Molecule FISH at the Drosophila Neuromuscular Junction

The lack of an effective, simple, and highly sensitive protocol for fluorescent in situ hybridization (FISH) at the Drosophila larval neuromuscular junction (NMJ) has hampered the study of mRNA biology. Here, we describe our modified single molecule FISH (smFISH) methods that work well in whole mount Drosophila NMJ preparations to quantify primary transcription and count individual cytoplasmic mRNA molecules in specimens while maintaining ultrastructural preservation. The smFISH method is suitable for high-throughput sample processing and 3D image acquisition using any conventional microscopy imaging modality and is compatible with the use of antibody colabeling and transgenic fluorescent protein tags in axons, glia, synapses, and muscle cells. These attributes make the method particularly amenable to super-resolution imaging. With 3D Structured Illumination Microscopy (3D-SIM), which increases spatial resolution by a factor of 2 in X, Y, and Z, we acquire super-resolution information about the distribution of single molecules of mRNA in relation to covisualized synaptic and cellular structures. Finally, we demonstrate the use of commercial and open source software for the quality control of single transcript expression analysis, 3D-SIM data acquisition and reconstruction as well as image archiving management and presentation. Our methods now allow the detailed mechanistic and functional analysis of sparse as well as abundant mRNAs at the NMJ in their appropriate cellular context.

Dynamic Behavior of the RNA Polymerase II and the Ubiquitin Proteasome System During the Neuronal DNA Damage Response to Ionizing Radiation

Neurons are highly vulnerable to genotoxic agents. To restore genome integrity upon DNA lesions, neurons trigger a DNA damage response (DDR) that requires chromatin modifications and transcriptional silencing at DNA damage sites. To study the reorganization of the active RNA polymerase II (Pol II), which transcribes all mRNA-encoding genes, and the participation of the ubiquitin-proteasome system (UPS) in the neuronal DDR, we have used rat sensory ganglion neurons exposed to X-rays (4 Gy) ionizing radiation (IR). In control neurons, Pol II appears concentrated in numerous chromatin microfoci identified as transcription factories by the incorporation of 5'-fluorouridine into nascent RNA. Upon IR treatment, numerous IR-induced foci (IRIF), which were immunoreactive for γH2AX and 53BP1, were observed as early as 30 min post-IR; their number progressively reduced at 3 h, 1 day, and 3 days post-IR. The formation of IRIF was associated with a decrease in Pol II levels by both immunofluorescence and Western blotting. Treatment with the proteasome inhibitor bortezomib strongly increased Pol II levels in both control and irradiated neurons, suggesting that proteasome plays a proteolytic role by clearing stalled Pol II complexes at DNA damage sites, as a prelude to DNA repair. Neuronal IRIF recruited ubiquitylated proteins, including ubiquitylated histone H2A (Ub-H2A), and the catalytic proteasome 20S. Ub-H2A has been associated with transcriptional silencing at DNA damage sites. On the other hand, the participation of UPS in neuronal DDR may be essential for the ubiquitylation of Pol II and other proteasome substrates of the DNA repair machinery and their subsequent proteasome-mediated degradation.

Chronic Alcohol Exposure Decreases 53BP1 Protein Levels Leading to a Defective DNA Repair in Cultured Primary Cortical Neurons

Chronic alcohol consumption may cause neurodevelopmental and neurodegenerative disorders. Alcohol neurotoxicity is associated with the production of acetaldehyde and reactive oxygen species that induce oxidative DNA damage. However, the molecular mechanisms by which ethanol disturbs the DNA damage response (DDR), resulting in a defective DNA repair, remain unknown. Here, we have used cultured primary cortical neurons exposed to 50 or 100 mM ethanol for 7 days to analyze the ethanol-induced DDR. Ethanol exposure produced a dose-dependent generation of double strand breaks and the formation of DNA damage foci immunoreactive for the histone γH2AX, a DNA damage marker, and for the ubiquitylated H2A, which is involved in chromatin remodeling at DNA damage sites. Importantly, these DNA damage foci failed to recruit the protein 53BP1, a crucial DNA repair factor. This effect was associated with a drop in 53BP1 mRNA and protein levels and with an inhibition of global transcription. Moreover, ethanol-exposed neurons treated with ionizing radiation (2 Gy) also failed to recruit 53BP1 at DNA damage foci and exhibited a greater vulnerability to DNA lesions than irradiated control neurons. Our results support that defective DNA repair, mediated by the deficient expression and recruitment of 53BP1 to DNA damage sites, represents a novel mechanism involved in ethanol neurotoxicity. The design of therapeutic strategies that increase or stabilize 53BP1 levels might potentially promote DNA repair and partially compensate alcohol neurotoxicity.

The SMN Tudor SIM-like domain is key to SmD1 and coilin interactions and to Cajal body biogenesis

Cajal bodies (CBs) are nuclear organelles involved in the maturation of spliceosomal small nuclear ribonucleoproteins (snRNPs). They concentrate coilin, snRNPs and the survival motor neuron protein (SMN). Dysfunction of CB assembly occurs in spinal muscular atrophy (SMA). Here, we demonstrate that SMN is a SUMO1 target that has a small ubiquitin-related modifier (SUMO)-interacting motif (SIM)-like motif in the Tudor domain. The expression of SIM-like mutant constructs abolishes the interaction of SMN with the spliceosomal SmD1 (also known as SNRPD1), severely decreases SMN-coilin interaction and prevents CB assembly. Accordingly, the SMN SIM-like-mediated interactions are important for CB biogenesis and their dysfunction can be involved in SMA pathophysiology.

Reactive nucleolar and Cajal body responses to proteasome inhibition in sensory ganglion neurons

The dysfunction of the ubiquitin proteasome system has been related to a broad array of neurodegenerative disorders in which the accumulation of misfolded protein aggregates causes proteotoxicity. The ability of proteasome inhibitors to induce cell cycle arrest and apoptosis has emerged as a powerful strategy for cancer therapy. Bortezomib is a proteasome inhibitor used as an antineoplastic drug, although its neurotoxicity frequently causes a severe sensory peripheral neuropathy. In this study we used a rat model of bortezomib treatment to study the nucleolar and Cajal body responses to the proteasome inhibition in sensory ganglion neurons that are major targets of bortezomib-induced neurotoxicity. Treatment with bortezomib induced dose-dependent dissociation of protein synthesis machinery (chromatolysis) and nuclear retention of poly(A) RNA granules resulting in neuronal dysfunction. However, as a compensatory response to the proteotoxic stress, both nucleoli and Cajal bodies exhibited reactive changes. These include an increase in the number and size of nucleoli, strong nucleolar incorporation of the RNA precursor 5'-fluorouridine, and increased expression of both 45S rRNA and genes encoding nucleolar proteins UBF, fibrillarin and B23. Taken together, these findings appear to reflect the activation of the nucleolar transcription in response to proteotoxic stress Furthermore, the number of Cajal bodies, a parameter related to transcriptional activity, increases upon proteasome inhibition. We propose that nucleoli and Cajal bodies are important targets in the signaling pathways that are activated by the proteotoxic stress response to proteasome inhibition. The coordinating activity of these two organelles in the production of snRNA, snoRNA and rRNA may contribute to neuronal survival after proteasome inhibition. This article is part of a Special Issue entitled: Role of the Nucleolus in Human Disease.

Autophagy during beef aging

The conversion of muscle into meat is a complex process of major concern for meat scientists due to its influence on the final meat quality. The aim of this study was to investigate the occurrence of autophagic processes in the conversion of muscle into meat. Our findings demonstrated, for the first time, the occurrence of autophagic processes in the muscle tissue at early postmortem period (2 h to 24 h) in both beef breeds studied (Asturiana de los Valles and Asturiana de la Montaña) showing significant time-scale differences between breeds, which could indicate a role of this process in meat maturation. These breeds have different physiological features: while Asturiana de los Valles is a meat-specialized breed showing high growth rate, an elevated proportion of white fibers in the muscle and low intramuscular fat level, Asturiana de la Montaña is a small- to medium-sized rustic breed adapted to less-favored areas, showing more red fibers in the muscle and a high intramuscular fat content.

Effect of ionizing radiation in sensory ganglion neurons: organization and dynamics of nuclear compartments of DNA damage/repair and their relationship with transcription and cell cycle

Neurons are very sensitive to DNA damage induced by endogenous and exogenous genotoxic agents, as defective DNA repair can lead to neurodevelopmental disorders, brain tumors and neurodegenerative diseases with severe clinical manifestations. Understanding the impact of DNA damage/repair mechanisms on the nuclear organization, particularly on the regulation of transcription and cell cycle, is essential to know the pathophysiology of defective DNA repair syndromes. In this work, we study the nuclear architecture and spatiotemporal organization of chromatin compartments involved in the DNA damage response (DDR) in rat sensory ganglion neurons exposed to X-ray irradiation (IR). We demonstrate that the neuronal DDR involves the formation of two categories of DNA-damage processing chromatin compartments: transient, disappearing within the 1 day post-IR, and persistent, where unrepaired DNA is accumulated. Both compartments concentrate components of the DDR pathway, including γH2AX, pATM and 53BP1. Furthermore, DNA damage does not induce neuronal apoptosis but triggers the G0-G1 cell cycle phase transition, which is mediated by the activation of the ATM-p53 pathway and increased protein levels of p21 and cyclin D1. Moreover, the run on transcription assay reveals a severe inhibition of transcription at 0.5 h post-IR, followed by its rapid recovery over the 1 day post-IR in parallel with the progression of DNA repair. Therefore, the response of healthy neurons to DNA damage involves a transcription- and cell cycle-dependent but apoptosis-independent process. Furthermore, we propose that the segregation of unrepaired DNA in a few persistent chromatin compartments preserves genomic stability of undamaged DNA and the global transcription rate in neurons.