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OBJECTIVE: Leucine-rich α-2 glycoprotein 1 (LRG1) was recently identified as an amplifier of transforming growth factor-β (TGF-β)–induced kidney fibrosis in animal models. We aimed to study whether urine LRG1 is associated with risk of progression to end-stage kidney disease (ESKD) in individuals with type 2 diabetes. RESEARCH DESIGN AND METHODS: A total of 1,837 participants with type 2 diabetes and estimated glomerular filtration rate (eGFR) >30 mL/min/1.73 m2 were recruited from a regional hospital and a primary care facility. Association of urine LRG1 with risk of ESKD (progression to sustained eGFR <15 mL/min/1.73 m2, dialysis, or death resulting from renal causes) was assessed by survival analyses. RESULTS: During a median follow-up of 8.6 (interquartile range 5.8–9.6) years, 134 incident ESKD events were identified. Compared with those in the lowest tertile, participants with baseline urine LRG1 in the highest tertile had a 1.91-fold (95% CI 1.04–3.50) increased risk of progression to ESKD, after adjustment for cardiorenal risk factors, including eGFR and albuminuria. As a continuous variable, 1 SD increment in urine LRG1 was associated with a 1.53-fold (95% CI 1.19–1.98) adjusted risk of ESKD. Of note, the association of urine LRG1 with ESKD was independent of plasma LRG1. Moreover, urine LRG1 was associated with rapid kidney function decline and progression to macroalbuminuria, two common pathways leading to ESKD. CONCLUSIONS: Urine LRG1, a TGF-β signaling modulator, predicts risk of progression to ESKD independently of clinical risk factors in patients with type 2 diabetes, suggesting that it may be a novel factor involved in the pathophysiological pathway leading to kidney disease progression. [ABSTRACT FROM AUTHOR]

Context: Early-onset diabetes has been associated with unfavorable cardiovascular risk but data on heart failure (HF) in this subpopulation are scarce. Objective: We aimed to study the risk of, and risk factors for, incident HF in individuals with early-onset type 2 diabetes. Methods: We studied 606 individuals with type 2 diabetes diagnosed before 40 years of age (early-onset) and 1258 counterparts with diabetes diagnosed from 41 to 65 years of age (usual-onset) with no HF history, at a regional hospital, over a median follow-up period of 7.1 years. Incident HF by European Cardiology Society criteria was determined. Results: A total of 62 and 108 HF events were identified in the early- and usual-onset groups (1.55 and 1.29 per 100 patient-years), respectively. Compared with usual-onset counterparts, individuals with early-onset diabetes had a 1.20-fold unadjusted (95% CI, 0.88-1.63; P = 0.26) and 1.91-fold age-adjusted (95% CI, 1.37-2.66; P < 0.001) hazard ratio (HR) for incident HF. Adjustment for traditional cardiometabolic risk factors only moderately mitigated the hazards (adjusted HR 1.69; 95% CI, 1.19-2.40; P = 0.003). However, additional adjustment for estimated glomerular filtration rate and albuminuria markedly attenuated the association of early-onset age with incident HF (adjusted HR 1.24; 95% CI, 0.87-1.77; P = 0.24). Notably, a long diabetes duration was not significantly associated with HF risk after accounting for kidney measures. Conclusion: Individuals with early-onset diabetes have at least the same absolute risk and a 2-fold age-adjusted relative risk for incident HF. Excess cardiorenal risk factors but not a long diabetes duration are main drivers for HF development in this diabetic population. [ABSTRACT FROM AUTHOR]

Objective: Leucine-rich α-2 glycoprotein 1 (LRG1) is a circulating protein potentially involved in several pathways related to pathogenesis of heart failure (HF). We aimed to study whether plasma LRG1 is associated with risks of incident HF and hospitalization attributable to HF (HHF) in individuals with type 2 diabetes.Research Design and Methods: A total of 1,978 individuals with type 2 diabetes were followed for a median of 7.1 years (interquartile range 6.1-7.6). Association of LRG1 with HF was studied using cause-specific Cox regression models.Results: In follow-up, 191 incident HF and 119 HHF events were identified. As compared with quartile 1, participants with LRG1 in quartiles 3 and 4 had 3.60-fold (95% CI 1.63-7.99) and 5.99-fold (95% CI 2.21-16.20) increased risk of incident HF and 5.88-fold (95% CI 1.83-18.85) and 10.44-fold (95% CI 2.37-45.98) increased risk of HHF, respectively, after adjustment for multiple known cardiorenal risk factors. As a continuous variable, 1 SD increment in natural log-transformed LRG1 was associated with 1.78-fold (95% CI 1.33-2.38) adjusted risk of incident HF and 1.92-fold (95% CI 1.27-2.92) adjusted risk of HHF. Adding LRG1 to the clinical variable-based model improved risk discrimination for incident HF (area under the curve [AUC] 0.79-0.81; P = 0.02) and HHF (AUC 0.81-0.84; P = 0.02).Conclusions: Plasma LRG1 is associated with risks of incident HF and HHF, suggesting that it may potentially be involved in pathogenesis of HF in individuals with type 2 diabetes. Additional studies are warranted to determine whether LRG1 is a novel biomarker for HF risk stratification. [ABSTRACT FROM AUTHOR]

Objective: Haptoglobin is an acute-phase reactant with pleiotropic functions. We aimed to study whether urine haptoglobin may predict risk of mortality in people with type 2 diabetes.Research Design and Methods: We employed a transethnic approach with a cohort of Asian origin (Singapore) (N = 2,061) and a cohort of European origin (France) (N = 1,438) included in the study. We used survival analyses to study the association of urine haptoglobin with risk of all-cause and cause-specific mortality.Results: A total of 365 and 525 deaths were registered in the Singapore cohort (median follow-up 7.5 years [interquartile range 3.5-12.8]) and French SURDIAGENE cohort (median follow-up 6.8 years [interquartile range 4.3-10.5], respectively. Singapore participants with urine haptoglobin in quartiles 2 to 4 had higher risk for all-cause mortality compared with quartile 1 (unadjusted hazard ratio [HR] 1.47 [95% CI 1.02-2.11], 2.28 [1.62-3.21], and 4.64 [3.39-6.35], respectively). The association remained significant in quartile 4 after multiple adjustments (1.68 [1.15-2.45]). Similarly, participants in the French cohort with haptoglobin in quartile 4 had significantly higher hazards for all-cause mortality compared with quartile 1 (unadjusted HR 2.67 [2.09-3.42] and adjusted HR 1.49 [1.14-1.96]). In both cohorts, participants in quartile 4 had a higher risk of mortality attributable to cardiovascular disease and infection but not malignant tumor.Conclusions: Urine haptoglobin predicts risk of mortality independent of traditional risk factors, suggesting that it may potentially be a novel biomarker for risk of mortality in patients with type 2 diabetes. [ABSTRACT FROM AUTHOR]

Background The progression trajectory of renal filtration function has not been well characterized in patients with early-onset type 2 diabetes mellitus (T2DM) although albuminuria is often reported in this population. We aim to study the risk of progressive chronic kidney disease (CKD) in individuals with early-onset T2DM. Methods In total, 1189 T2DM participants were followed for 3.9 (interquartile range 3.2–4.7) years. Progressive CKD was defined as estimated glomerular filtration rate (eGFR) decline of ≥5 mL/min/1.73 m2 per year. Early-onset T2DM was defined as age at T2DM diagnosis between 18 and 30 years. Results Compared with later-onset counterparts (N  = 1032), participants with early-onset T2DM (N  = 157) were more obese and had poorer glycaemic control at baseline. In the follow-up, 24.2% and 15.6% experienced progressive CKD in early-onset and later-onset participants, respectively (P = 0.007). Logistic regression suggested that participants with early-onset T2DM had 2.63-fold [95% confidence interval (CI) 1.46–4.75] higher risk of progressive CKD after accounting for multiple traditional risk factors. Furthermore, the excess risk of progressive CKD associated with early-onset T2DM mainly occurred in participants with preserved renal function [eGFR ≥60 mL/min/1.73 m2, odds ratio (OR) 2.85, 95% CI 1.50–5.42] and was more pronounced in those with diabetes duration <10 years (OR 3.67, 95% CI 1.51–8.90). Conclusions Individuals with early-onset T2DM have a higher risk of progressive CKD. The excess risk mainly exhibits in early stage of CKD and cannot be solely attributed to traditional risk factors and a longer diabetes duration. [ABSTRACT FROM AUTHOR]

Background The telomerase enzyme is a viable target for anti-cancer therapy given the innate differences in telomerase activity between tumour cells and normal somatic cells. However, the time lag between telomerase inhibition and telomeres becoming critically short to trigger cell death, allows cancer cells to acquire drug resistance. Inhibition of DNA repair pathways along with telomerase could be an alternative strategy to enhance anti-tumour effects and circumvent the possibility of drug resistance. Poly (ADP-Ribose) Polymerase-1 (PARP-1), an important DNA damage sensor and a DNA repair factor, has important roles in maintaining telomeres and chromosomal stability. In this study, the effects of combined inhibition of PARP-1 and telomerase in mouse embryonic fibroblasts (MEFs) following sodium arsenite exposure (a carcinogen and potent DNA damaging agent), were evaluated. Results Inhibition of PARP in telomerase deficient MEFs induced an increase in arsenite-induced DNA damage as compared to control cells. Combined inhibition also resulted in enhanced genomic instability, demonstrated by elevated micronuclei induction and chromosomal aberrations with decreased cell survival. In addition, telomerase inhibition in PARP-1 deficient MEFs led to greater telomere shortening and increased genomic instability. Conclusions Our study demonstrated that the co-inhibition of PARP-1 and telomerase in MEFs rendered cells more susceptible to DNA damaging agents. Hence, these results offer support for the use of combined inhibition of PARP-1 and telomerase as a strategy to minimise the problems associated with long-term telomerase inhibition in cancer therapeutics., Authors: Resham L Gurung [1]; Lakshmidevi Balakrishnan [1]; Rabindra N Bhattacharjee [2]; Jayapal Manikandan [1]; Srividya Swaminathan [1]; M Prakash Hande (corresponding author) [1] Background Telomeres are specialised dynamic structures [...]

Background and Aim The kidney is the main site for glucagon clearance. However, a recent study showed that hyperglucagonemia in patients with end-stage renal disease might not be caused by full-length intact glucagon. Additionally, the relationship between glucagon and renal function in early-stage chronic kidney disease (CKD) has not yet been characterized. We studied the association of fasting glucagon with renal function across a wide range of glomerular filtration rates (GFRs) in participants with type 2 diabetes. Participants and Methods 326 participants with type 2 diabetes and renal function spanning CKD stage 1 to 5 were included in the present cross-sectional study. Fasting full-length plasma glucagon was quantified using a newly developed ELISA (Mercodia AB, Uppsala, Sweden). Results The fasting plasma glucagon level was elevated linearly from CKD stage 1 to 5 [from a median of 2.5 pM (interquartile range, 1.4 to 4.7) in CKD 1 to a median of 8.3 pM (interquartile range, 5.9 to 12.8) in CKD 5; P for trend < 0.0001], from as early as CKD stage 2 compared with that in stage 1 (Bonferroni-corrected P < 0.0001). The estimated GFR and homeostatic model of assessment–insulin resistance were the main determinants of the fasting glucagon level. These explained 14.3% and 10.3% of the glucagon variance, respectively. Albuminuria was not associated with fasting glucagon after adjustment for estimated GFR. Conclusions Fasting full-length glucagon was elevated linearly with the deterioration in renal function in individuals with type 2 diabetes, even in those with early CKD. In addition to renal function, insulin sensitivity was also a main determinant of glucagon variance. [ABSTRACT FROM AUTHOR]

Elongation of the telomeric overhang by telomerase is counteracted by synthesis of the complementary strand by the CST complex, CTC1(Cdc13)/Stn1/Ten1. Interaction of budding yeast Stn1 with overhang-binding Cdc13 is increased by Cdc13 SUMOylation. Human and fission yeast CST instead interact with overhang-binding TPP1/ POT1. We show that the fission yeast TPP1 ortholog, Tpz1, is SUMOylated. Tpz1 SUMOylation restricts telomere elongation and promotes Stn1/Ten1 telomere association, and a SUMO-Tpz1 fusion protein has increased affinity for Stn1. Our data suggest that SUMO inhibits telomerase through stimulation of Stn1/Ten1 action by Tpz1, highlighting the evolutionary conservation of the regulation of CST function by SUMOylation. [ABSTRACT FROM AUTHOR]

Objective: Haptoglobin is an acute-phase reactant with pleiotropic functions. We aimed to study whether urine haptoglobin may predict risk of mortality in people with type 2 diabetes., Research Design and Methods: We employed a transethnic approach with a cohort of Asian origin (Singapore) ( N = 2,061) and a cohort of European origin (France) ( N = 1,438) included in the study. We used survival analyses to study the association of urine haptoglobin with risk of all-cause and cause-specific mortality., Results: A total of 365 and 525 deaths were registered in the Singapore cohort (median follow-up 7.5 years [interquartile range 3.5-12.8]) and French SURDIAGENE cohort (median follow-up 6.8 years [interquartile range 4.3-10.5], respectively. Singapore participants with urine haptoglobin in quartiles 2 to 4 had higher risk for all-cause mortality compared with quartile 1 (unadjusted hazard ratio [HR] 1.47 [95% CI 1.02-2.11], 2.28 [1.62-3.21], and 4.64 [3.39-6.35], respectively). The association remained significant in quartile 4 after multiple adjustments (1.68 [1.15-2.45]). Similarly, participants in the French cohort with haptoglobin in quartile 4 had significantly higher hazards for all-cause mortality compared with quartile 1 (unadjusted HR 2.67 [2.09-3.42] and adjusted HR 1.49 [1.14-1.96]). In both cohorts, participants in quartile 4 had a higher risk of mortality attributable to cardiovascular disease and infection but not malignant tumor., Conclusions: Urine haptoglobin predicts risk of mortality independent of traditional risk factors, suggesting that it may potentially be a novel biomarker for risk of mortality in patients with type 2 diabetes., (© 2019 by the American Diabetes Association.)

Elongation of the telomeric overhang by telomerase is counteracted by synthesis of the complementary strand by the CST complex, CTC1(Cdc13)/Stn1/Ten1. Interaction of budding yeast Stn1 with overhang-binding Cdc13 is increased by Cdc13 SUMOylation. Human and fission yeast CST instead interact with overhang-binding TPP1/POT1. We show that the fission yeast TPP1 ortholog, Tpz1, is SUMOylated. Tpz1 SUMOylation restricts telomere elongation and promotes Stn1/Ten1 telomere association, and a SUMO-Tpz1 fusion protein has increased affinity for Stn1. Our data suggest that SUMO inhibits telomerase through stimulation of Stn1/Ten1 action by Tpz1, highlighting the evolutionary conservation of the regulation of CST function by SUMOylation., (© 2014 The Authors. Published under the terms of the CC BY 4.0 License.)