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Elevated serum urate (hyperuricemia) promotes crystalline monosodium urate tissue deposits and gout, with associated inflammation and increased mortality. To identify modifiers of uric acid pathologies, we performed a fly Genome-Wide Association Study (GWAS) on purine metabolites using the Drosophila Genetic Reference Panel strains. We tested the candidate genes using the Drosophila melanogaster model of hyperuricemia and uric acid crystallization ("concretion formation") in the kidney-like Malpighian tubule. Medusa (mda) activity increased urate levels and inflammatory response programming. Conversely, whole-body mda knockdown decreased purine synthesis precursor phosphoribosyl pyrophosphate, uric acid, and guanosine levels; limited formation of aggregated uric acid concretions; and was sufficient to rescue lifespan reduction in the fly hyperuricemia and gout model. Levels of mda homolog FAM214A were elevated in inflammatory M1- and reduced in anti-inflammatory M2-differentiated mouse bone marrow macrophages, and influenced intracellular uric acid levels in human HepG2 transformed hepatocytes. In conclusion, mda/FAM214A acts in a conserved manner to regulate purine metabolism, promotes disease driven by hyperuricemia and associated tissue inflammation, and provides a potential novel target for uric acid-driven pathologies.

Neurodegeneration is a major age-related pathology. Cognitive decline is characteristic of patients with Alzheimer's and related dementias and cancer patients after chemo- or radio-therapies. A recently emerged driver of these and other age-related pathologies is cellular senescence, a cell fate that entails a permanent cell cycle arrest and pro-inflammatory senescence-associated secretory phenotype (SASP). Although there is a link between inflammation and neurodegenerative diseases, there are many open questions regarding how cellular senescence affects neurodegenerative pathologies. Among the various cell types in the brain, astrocytes are the most abundant. Astrocytes have proliferative capacity and are essential for neuron survival. Here, we investigated the phenotype of primary human astrocytes made senescent by X-irradiation, and identified genes encoding glutamate and potassium transporters as specifically downregulated upon senescence. This down regulation led to neuronal cell death in co-culture assays. Unbiased RNA sequencing of transcripts expressed by non-senescent and senescent astrocytes confirmed that glutamate homeostasis pathway declines upon senescence. Our results suggest a key role for cellular senescence, particularly in astrocytes, in excitotoxicity, which may lead to neurodegeneration including Alzheimer's disease and related dementias.

Cellular senescence irreversibly arrests cell proliferation, accompanied by a multi-component senescence-associated secretory phenotype (SASP) that participates in several age-related diseases. Using stable isotope labeling with amino acids (SILACs) and cultured cells, we identify 343 SASP proteins that senescent human fibroblasts secrete at 2-fold or higher levels compared with quiescent cell counterparts. Bioinformatic analysis reveals that 44 of these proteins participate in hemostasis, a process not previously linked with cellular senescence. We validated the expression of some of these SASP factors in cultured cells and in vivo. Mice treated with the chemotherapeutic agent doxorubicin, which induces widespread cellular senescence in vivo, show increased blood clotting. Conversely, selective removal of senescent cells using transgenic p16-3MR mice showed that clearing senescent cells attenuates the increased clotting caused by doxorubicin. Our study provides an in-depth, unbiased analysis of the SASP and unveils a function for cellular senescence in hemostasis.

Sodium-glucose cotransporter (SGLT) inhibitors are new oral antidiabetes medications shown to effectively reduce glycated hemoglobin (A1C) and glycemic variability, blood pressure, and body weight without intrinsic properties to cause hypoglycemia in people with type 1 diabetes. However, recent studies, particularly in individuals with type 1 diabetes, have demonstrated increases in the absolute risk of diabetic ketoacidosis (DKA). Some cases presented with near-normal blood glucose levels or mild hyperglycemia, complicating the recognition/diagnosis of DKA and potentially delaying treatment. Several SGLT inhibitors are currently under review by the U.S. Food and Drug Administration and European regulatory agencies as adjuncts to insulin therapy in people with type 1 diabetes. Strategies must be developed and disseminated to the medical community to mitigate the associated DKA risk. This Consensus Report reviews current data regarding SGLT inhibitor use and provides recommendations to enhance the safety of SGLT inhibitors in people with type 1 diabetes.

Morquio A syndrome (mucopolysaccharidosis IVA) is an autosomal recessive disorder that results from deficient activity of the enzyme N-acetylgalactosamine-6-sulfatase (GALNS) due to alterations in the GALNS gene, which causes major skeletal and connective tissue abnormalities and effects on multiple organ systems. The GALNS alterations associated with Morquio A are numerous and heterogeneous, and new alterations are continuously identified. To aid detection and interpretation of GALNS alterations, from previously published research, we provide a comprehensive and up-to-date listing of 277 unique GALNS alterations associated with Morquio A identified from 1,091 published GALNS alleles. In agreement with previous findings, most reported GALNS alterations are missense changes and even the most frequent alterations are relatively uncommon. We found that 48% of patients are assessed as homozygous for a GALNS alteration, 39% are assessed as heterozygous for two identified GALNS alterations, and in 13% of patients only one GALNS alteration is detected. We report here the creation of a locus-specific database for the GALNS gene (http://galns.mutdb.org/) that catalogs all reported alterations in GALNS to date. We highlight the challenges both in alteration detection and genotype-phenotype interpretation caused in part by the heterogeneity of GALNS alterations and provide recommendations for molecular testing of GALNS.

Background. Detection of type 1 diabetes (T1D) at the preclinical stage is possible by detecting islet autoantibodies (IAs) years before the appearance of symptomatic diabetes. The Antibody Detection Israeli Research is a general population screening program searching for children with multiple IAs who are at risk of developing T1D. IAs are measured in capillary or venous whole blood (WB) samples using the novel ultrasensitive antibody detection by agglutination-PCR (ADAP) technology. Objective. To assess the accuracy and reliability of the ADAP assay in venous and capillary WB. Materials and Methods. In total, 50 children with T1D and 50 healthy controls participated in the study. Venous and capillary blood samples were drawn from participants with T1D, while only venous blood was drawn from the controls. The ADAP assay in venous and capillary blood was compared to the currently used assays in their ability to detect glutamic acid decarboxylase (GADA), islet antigen-2 (IA-2A), and insulin autoantibodies (IAAs). Results. The area under the curve using the receiver operating characteristic curves was comparable between the ADAP assay in WB and standard enzyme-linked immunosorbent assay (ELISA)/radioimmunoassay (RIA) for all three IAs GADA 0.946 (95% CI: 0.900–0.991) vs. 0.949 (0.906–0.992), P = 0.873 ; IA-2A 0.747 (0.649–0.844) vs. 0.666 (0.587–0.744), P = 0.106 ; IAA 1.000 (1.000–1.000) vs. 1.000 (1.000–1.000), P = 1.000. The correlation between the levels of IA in venous and capillary WB using ADAP was R2 = 0.958 (P < 0.01), R2 = 0.943 (P < 0.01), and R2 = 0.711 (P < 0.01) for GADA, IA-2A, and IAA, respectively. IA levels in venous and capillary WB using ADAP were comparable without a proportional bias in Bland–Altman's plots of agreement, suggesting the two methods may be used interchangeably. Conclusions. The ADAP assay is reliable in detecting IA in venous and capillary WB samples with comparable performance to standard RIA and ELISA. These findings open avenues for widespread use of the ADAP assay in future general population screening programs to detect children at risk of developing T1D. [ABSTRACT FROM AUTHOR]

Automated annotation of protein function is challenging. As the number of sequenced genomes rapidly grows, the overwhelming majority of protein products can only be annotated computationally. If computational predictions are to be relied upon, it is crucial that the accuracy of these methods be high. Here we report the results from the first large-scale community-based critical assessment of protein function annotation (CAFA) experiment. Fifty-four methods representing the state of the art for protein function prediction were evaluated on a target set of 866 proteins from 11 organisms. Two findings stand out: (i) today's best protein function prediction algorithms substantially outperform widely used first-generation methods, with large gains on all types of targets; and (ii) although the top methods perform well enough to guide experiments, there is considerable need for improvement of currently available tools.

Objective: This pooled analysis assessed continuous glucose monitoring (CGM) in patients with inadequately controlled type 1 diabetes (HbA1c ≥7.7 to ≤11.0% [≥61 to ≤97 mmol/mol]) who received dapagliflozin as an adjunct to adjustable insulin.Research Design and Methods: CGM data were pooled from two 24-week, double-blind, randomized, phase 3 studies: Dapagliflozin Evaluation in Patients with Inadequately Controlled Type 1 Diabetes (DEPICT-1 and DEPICT-2). These studies comprised 1,591 patients receiving dapagliflozin 5 mg (n = 530), dapagliflozin 10 mg (n = 529), or placebo (n = 532).Results: Baseline characteristics were balanced between treatment groups. Patients receiving dapagliflozin 5 mg or 10 mg both spent more time with blood glucose in the range >3.9 to ≤10.0 mmol/L (>70 to ≤180 mg/dL) over 24 h than those receiving the placebo. The adjusted mean (SE) change from baseline at week 24 was 6.48% (0.60) with dapagliflozin 5 mg, 8.08% (0.60) with dapagliflozin 10 mg, and -2.59% (0.61) with placebo. At week 24, the mean amplitude of glucose excursion over 24 h, mean 24-h glucose values, and postprandial glucose values were also improved in patients receiving dapagliflozin over those receiving placebo. No marked differences were found at week 24 between dapagliflozin 5 or 10 mg and placebo in the percentage of glucose values ≤3.9 mmol/L (≤70 mg/dL) or ≤3.0 mmol/L (≤54 mg/dL) over 24 h, or in nocturnal (0000-0559 h) glucose values ≤3.9 mmol/L (≤70 mg/dL).Conclusions: In patients with type 1 diabetes, treatment with dapagliflozin over 24 weeks improved time in range, mean glucose, and glycemic variability without increasing the time spent in the range indicating hypoglycemia. [ABSTRACT FROM AUTHOR]

Aims: To compare insulin dose adjustments made by physicians to those made by an artificial intelligence-based decision support system, the Advisor Pro, in people with type 1 diabetes (T1D) using an insulin pump and self-monitoring blood glucose (SMBG)., Methods: This was a multinational, non-interventional study surveying 17 physicians from 11 countries. Each physician was asked to provide insulin dose adjustments for the settings of the pump including basal rate, carbohydrate-to-insulin ratios (CRs), and correction factors (CFs) for 15 data sets of pumps and SMBG of people with T1D (mean age 18.4 ± 4.8 years; eight females; mean glycated hemoglobin 8.2% ± 1.4% [66 ± 11mmol/mol]). The recommendations were compared among the physicians and between the physicians and the Advisor Pro. The study endpoint was the percentage of comparison points for which there was an agreement on the direction of insulin dose adjustments., Results: The percentage (mean ± SD) of agreement among the physicians on the direction of insulin pump dose adjustments was 51.8% ± 9.2%, 54.2% ± 6.4%, and 49.8% ± 11.6% for the basal, CR, and CF, respectively. The automated recommendations of the Advisor Pro on the direction of insulin dose adjustments were comparable )49.5% ± 6.4%, 55.3% ± 8.7%, and 47.6% ± 14.4% for the basal rate, CR, and CF, respectively( and noninferior to those provided by physicians. The mean absolute difference in magnitude of change between physicians was 17.1% ± 13.1%, 14.6% ± 8.4%, and 23.9% ± 18.6% for the basal, CR, and CF, respectively, and comparable to the Advisor Pro 11.7% ± 9.7%, 10.1% ± 4.5%, and 25.5% ± 19.5%, respectively, significant for basal and CR., Conclusions: Considerable differences in the recommendations for changes in insulin dosing were observed among physicians. Since automated recommendations by the Advisor Pro were similar to those given by physicians, it could be considered a useful tool to manage T1D.

Background: Type 1 diabetes (T1D) contributes to altered lipid profiles and increases the risk of cardiovascular disease (CVD). Youth with T1D may have additional CVD risk factors within the first decade of diagnosis., Aim: To examine risk factors for dyslipidemia in young subjects with T1D., Methods: Longitudinal and cross-sectional retrospective study of 170 young subjects with T1D (86 males; baseline mean age 12.2 ± 5.6 years and hemoglobin A1c 8.4% ± 1.4%) were followed in a single tertiary diabetes center for a median duration of 15 years. Predictors for outcomes of lipid profiles at last visit (total cholesterol [TC], triglycerides [TGs], low-density lipoprotein-cholesterol [LDL-c], and high-density lipoprotein-cholesterol [HDL-c]) were analyzed by stepwise linear regression models., Results: At baseline, 79.5% of the patients had at least one additional CVD risk factor (borderline dyslipidemia/dyslipidemia [37.5%], pre-hypertension/hypertension [27.6%], and overweight/obesity [16.5%]) and 41.6% had multiple (≥ 2) CVD risk factors. A positive family history of at least one CVD risk factor in a first-degree relative was reported in 54.1% of the cohort. Predictors of elevated TC: family history of CVD (β[SE] = 23.1[8.3], P = 0.006); of elevated LDL-c: baseline diastolic blood pressure (DBP) (β[SE] = 11.4[4.7], P = 0.003) and family history of CVD (β[SE] = 20.7[6.8], P = 0.017); of elevated TGs: baseline DBP (β[SE] = 23.8[9.1], P = 0.010) and family history of CVD (β[SE] = 31.0[13.1], P = 0.020); and of low HDL-c levels: baseline DBP (β[SE] = 4.8[2.1], P = 0.022])., Conclusion: Our findings suggest that elevated lipid profiles are associated with DBP and a positive family history of CVD. It is of utmost importance to prevent and control modifiable risk factors such as these, as early as childhood, given that inadequate glycemic control and elevation in blood pressure intensify the risk of dyslipidemia., Competing Interests: Conflict-of-interest statement: All authors confirm that no potential conflicts of interest relevant to this article were reported., (©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.)