Preconception episodes of severe hypoglycemia and risk of adverse pregnancy outcomes in pregnant women with type 1 diabetes mellitus.

AIMS: To explore the relationship between preconception severe hypoglycemia (PSH) and pregnancy outcomes in pregnancies complicated with type 1 diabetes mellitus (T1DM). MATERIALS AND METHODS: In this multicenter prospective cohort study, women with pregestational T1DM were stratified by episodes of severe hypoglycemia within 1 year before conception: No PSH, sporadic PSH (1-6 times/year), and recurrent PSH (>6 times/year). We analysed the predictive ability of PSH for maternal and neonatal outcomes using log-binomial regression models and receiver operating characteristic (ROC) curve. RESULTS: Of the 124 women studied, 37.1% experienced at least one episode of severe hypoglycemia preconception. In the multiple adjusted regression models, recurrent PSH was significantly associated with increased incidence of preeclampsia (RR 17.59, 95% CI: 2.89-150.62, p for trend = 0.007), preterm birth (RR 6.34, 95% CI: 1.22-40.63, p for trend = 0.027), neonatal hypoglycemia (RR 4.52, 95% CI: 1.14-17.16, p for trend = 0.017), neonatal hyperbilirubinemia (RR 4.12, 95% CI: 1.11-15.56, p for trend = 0.004), and composite neonatal outcome (RR 3.85, 95% CI: 1.01-19.61, p for trend = 0.003). In the ROC analysis, PSH predicted preeclampsia, preterm birth, neonatal hypoglycemia, neonatal hyperbilirubinemia, and composite neonatal outcome with areas under the ROC curve all ≥0.6. CONCLUSIONS: Recurrent preconception severe hypoglycemia is associated with increased risks of adverse outcomes in pregnant women with T1DM.

High Vasohibin-2 expression correlated with autophagy in proliferative diabetic retinopathy.

Vasohibin-2 (VASH2) is confirmed to be associated with angiogenesis. To investigate the vitreous levels of VASH2 and how VASH2 induces angiogenesis in proliferative diabetic retinopathy (PDR), a total of 120 eyes were enrolled in this prospective and randomized controlled study and the vitreous level of VASH2 was quantified by Luminex liquid suspension chip. Vector systems were applied in human retinal microvascular endothelial cells (HRMECs) for VASH2 gene overexpression, along with interfering lentiviral vectors (VASH2-shRNA) for VASH2 gene silencing. Cell migration, autophagic flux, as well as the expression of α-tubulin, detyrosinated ⍺-tubulin, LC3 II/LC3 I, P62 were detected under normal, VASH2 overexpression, or interference conditions. The level of VASH2 in PDR patients was significantly higher (218.61 ± 30.14 pg/ml) than that in ERM/MH patients (80.78 ± 2.05 pg/ml) (P = 0.001). The migration ability of HRMECs was significantly increased in VASH2 overexpression group, while in the interfering group, the migration ability decreased. VASH2 increased the detyrosination of ⍺-tubulin. The high fluorescence intensity of autophagic flux showed an activation of autophagy in VASH2 overexpression group, which was also confirmed by the increase of LC3 II/LC3 I ratio and the decrease of P62. Collectively, the present study shows in PDR, vitreous level of VASH2 is higher. VASH2 promotes neovascularization by inducing autophagy, suggesting VASH2 could be a new anti-angiogenic drug target for PDR.

Long-term exercise preserves pancreatic islet structure and ß-cell mass through attenuation of islet inflammation and fibrosis.

Islet fibrosis is associated with the disruption of islet structure and contributes to ß-cell dysfunction, playing an essential role in the pathogenesis of type 2 diabetes. Physical exercise has been shown to attenuate fibrosis in various organs; however, the effect of exercise on islet fibrosis has not been defined. Male Sprague-Dawley rats were divided into four groups: normal diet sedentary [N-Sed], normal diet + exercise [N-Ex], high-fat diet sedentary [H-Sed], and high-fat diet + exercise [H-Ex]. After 60 weeks of exercise, 4452 islets from Masson-stained slides were analyzed. Exercise led to a 68% and 45% reduction in islet fibrosis in the normal and high-fat diet groups and was correlated with a lower serum blood glucose. Fibrotic islets were characterized by irregular shapes and substantial loss of ß-cell mass, which were significantly reduced in the exercise groups. Remarkably, the islets from exercised rats at week 60 were morphologically comparable to those of sedentary rats at 26 weeks. In addition, the protein and RNA levels of collagen and fibronectin, and the protein levels of hydroxyproline in the islets were also attenuated by exercise. This was accompanied by a significant reduction in inflammatory markers in the circulation Interleukin-1 beta (IL-1ß)] and pancreas [IL-1ß, Tumor Necrosis Factor-alpha, Transforming Growth Factor-ß, and Phosphorylated Nuclear Factor Kappa-B p65 subunit], lower macrophage infiltration, and stellate cell activation in the islets of exercised rats. In conclusion, we have demonstrated that long-term exercise preserves pancreatic islet structure and ß-cell mass through anti-inflammatory and anti-fibrotic actions, suggesting additional rationales for the success of exercise training in the prevention and treatment of type 2 diabetes that should be further explored.

Mouse islet-derived stellate cells are similar to, but distinct from, mesenchymal stromal cells and influence the beta cell function.

AIMS: Evidence is accumulating of the therapeutic benefits of mesenchymal stromal cells (MSCs) in diabetes-related conditions. We have identified a novel population of stromal cells within islets of Langerhans - islet stellate cells (ISCs) - which have a similar morphology to MSCs. In this study we characterize mouse ISCs and compare their morphology and function to MSCs to determine whether ISCs may also have therapeutic potential in diabetes. METHODS: ISCs isolated from mouse islets were compared to mouse bone marrow MSCs by analysis of cell morphology; expression of cell-surface markers and extracellular matrix (ECM) components; proliferation; apoptosis; paracrine activity; and differentiation into adipocytes, chondrocytes and osteocytes. We also assessed the effects of co-culture with ISCs or MSCs on the insulin secretory capacity of islet beta cells. RESULTS: Although morphological similar, ISCs were functionally distinct from MSCs. Thus, ISCs were less proliferative and more apoptotic; they had different expression levels of important paracrine factors; and they were less efficient at differentiation down multiple lineages. Co-culture of mouse islets with ISCs enhanced glucose induced insulin secretion more effectively than co-culture with MSCs. CONCLUSIONS: ISCs are a specific sub-type of islet-derived stromal cells that possess biological behaviors distinct from MSCs. The enhanced beneficial effects of ISCs on islet beta cell function suggests that they may offer a therapeutic target for enhancing beta cell functional survival in diabetes.

Gastric emptying in newly diagnosed, treatment-naïve Han Chinese with type 2 diabetes and the impact of 4-week insulin pump therapy.

AIM: To evaluate gastric emptying (GE) and the glycaemic response to a 75-g oral glucose load in newly diagnosed, treatment-naïve Han Chinese with type 2 diabetes (T2D) before insulin pump therapy, after 4 weeks of insulin pump therapy, and 12-15 months after insulin pump therapy. MATERIALS AND METHODS: Twenty participants with T2D (baseline glycated haemoglobin [± SD] 10.7% [± 1.2%] 93 [± 10] mmol/mol) ingested a 75-g glucose drink containing 150 mg 13C-acetate, to determine the gastric half-emptying time, and underwent assessment of plasma glucose and serum insulin, C-peptide and glucagon-like peptide-1 (GLP-1) over 180 min before and after 4 weeks of insulin pump therapy (discontinued for 48 h before re-assessment). Data were compared to those in 19 healthy participants matched for sex and age. After 12-15 months, GE was re-measured in 14 of the T2D participants. RESULTS: At baseline, participants with T2D exhibited substantially augmented fasting and post-glucose glycaemia, diminished insulin secretion, and more rapid GE (p < 0.05 each), but comparable GLP-1, compared to healthy participants. Following insulin pump therapy, insulin secretion increased, GLP-1 secretion was attenuated, fasting and post-glucose glycaemia were lower, and GE was slowed (p < 0.05 each). The slowing of GE in T2D participants was sustained over 12-15 months of follow-up. CONCLUSIONS: In newly diagnosed Han Chinese with T2D, GE is often accelerated despite poor glycaemic control and is slowed by short-term insulin pump therapy. The effect on GE is maintained for at least 12 months.

Gastric emptying is slower in women than men with type 2 diabetes and impacts on postprandial glycaemia.

AIM: To evaluate sex differences in gastric emptying and the glycaemic response to a glucose drink and a high carbohydrate meal in type 2 diabetes (T2D). METHODS: In cohort 1, 70 newly diagnosed, treatment-naïve Chinese patients with T2D (44 men) recruited from a diabetes outpatient clinic ingested a 75-g glucose drink containing 150 mg 13C-acetate. In cohort 2, 101 Australian patients with T2D (67 male) recruited from the community, managed by diet and/or metformin monotherapy, ingested a semi-solid mashed potato meal, labelled with 100 µl 13C-octanoic acid. Breath samples were collected over 3 and 4 h, respectively, for assessment of gastric emptying, and venous blood was sampled for evaluation of glycaemia (with and without adjustment for each participant's estimated total blood volume). RESULTS: Gastric emptying was slower in female than male subjects in both cohorts (both p < .01). Multiple linear regression analyses revealed that gastric emptying was independently associated with sex (both p < .05). Without adjustment for blood volume, the glycaemic responses to oral glucose and the mixed meal were greater in female subjects (both p < .001). However, after adjustment for blood volume, the glycaemic responses were greater in men (both p < .05). CONCLUSIONS: Gastric emptying is slower in women than men with T2D, associated with a reduced blood volume-adjusted glycaemic response to oral glucose and a mixed meal in women. These observations highlight the sex difference in postprandial glucose handling, which is relevant to the personalized management of postprandial glycaemia in T2D.

HbA1c combined with glycated albumin or 1,5-anhydroglucitol improves the efficiency of diabetes screening in a Chinese population.

AIMS: This study aimed to evaluate the ability of HbA1c combined with glycated albumin (GA) or 1,5-anhydroglucitol (1,5-AG) to detect diabetes in residents of Jiangsu, China. METHODS: The oral glucose tolerance test (OGTT) was performed on 2184 people in Jiangsu. HbA1c , GA, 1,5-AG and other serum biochemical parameters were measured. Receiver operating characteristic curves were plotted to determine the optimal thresholds of HbA1c , GA and 1,5-AG according to the Youden index. RESULTS: (1) The optimal thresholds of HbA1c , GA and 1,5-AG for the screening of diabetes were ≥45 mmol/mol (6.3%), ≥13.0% and ≤23.0 µg/ml, respectively. (2) The sensitivities of HbA1c combined with GA and 1,5-AG were both 85%, higher than that of HbA1c (70%, p < 0.001). CONCLUSIONS: This study is suitable for cases where plasma glucose is unavailable. Among the residents of Jiangsu, HbA1c combined with GA or 1,5-AG can improve the sensitivity of diabetes screening, reduce the miss rate and save the use of OGTT. GA and 1,5-AG are superior in individuals with mild glucose metabolism disorder. GA enhances the detection of diabetes in the nonobese, and 1,5-AG enhances the detection in those with hyperuricaemia.

Cholecystectomy is associated with dysglycaemia: Cross-sectional and prospective analyses.

Cholecystectomy has been reported to be associated with increased risk of diabetes in cross-sectional studies. In the current study, we performed both cross-sectional and prospective analyses to examine the association between cholecystectomy and dysglycaemia in Chinese community-dwelling adults. A total of 1612 participants (n = 1564 without cholecystectomy and n = 48 with cholecystectomy) were evaluated for glycaemic status (according to the World Health Organization (WHO) 1999 criteria) and then followed up over ~3.2 years. Percent changes (Δ) in fasting blood glucose and HbA1c from baseline at the follow-up visit were calculated to define glycaemic control as stable (-10% ≤ Δ < 10%), improved (Δ < -10%), or worsened (Δ ≥ 10%). The baseline cross-sectional analyses indicated that cholecystectomy was associated with an increased risk of both prediabetes and diabetes, while the prospective analysis indicated that cholecystectomy was also associated with a greater risk of deterioration in glycaemic control (ΔFPG ≥10% and ΔHbA1c ≥10%) (P < 0.05 for each, both before and after adjusting for potential confounding covariates). These observations suggest that individuals in the Chinese community-dwelling population who have undergone cholecystectomy are at increased risk of dysglycaemia. Further studies are warranted to both delineate the underlying mechanisms and to clarify whether more intense surveillance for future development of diabetes is needed in this group.

Serum bile acid response to oral glucose is attenuated in patients with early type 2 diabetes and correlates with 2-hour plasma glucose in individuals without diabetes.

AIM: To determine the serum bile acid (BA) response to 75-g oral glucose in individuals without diabetes, and whether this is attenuated in patients with 'early' type 2 diabetes (T2D) and related to the glycaemic response at 2 hours in either group. METHODS: Forty newly diagnosed, treatment-naïve Han Chinese T2D subjects and 40 age-, gender-, and body mass index-matched controls without T2D ingested a 75-g glucose drink after an overnight fast. Plasma glucose and serum concentrations of total and individual BAs, fibroblast growth factor-19 (FGF-19), total glucagon-like peptide-1 (GLP-1), and insulin, were measured before and 2 hours after oral glucose. RESULTS: Fasting total BA levels were higher in T2D than control subjects (P < .05). At 2 hours, the BA profile exhibited a shift from baseline in both groups, with increases in conjugated BAs and/or decreases in unconjugated BAs. There were increases in total BA and FGF-19 levels in control (both P < .05), but not T2D, subjects. Plasma glucose concentrations at 2 hours related inversely to serum total BA levels in control subjects (r = -0.42, P = .006). Total GLP-1 and the insulin/glucose ratio were increased at 2 hours in both groups, and the magnitude of the increase was greater in control subjects. CONCLUSIONS: The serum BA response to a 75-g oral glucose load is attenuated in patients with 'early' T2D, as is the secretion of FGF-19 and GLP-1, while in individuals without T2D it correlates with 2-hour plasma glucose levels. These observations support a role for BAs in the regulation of postprandial glucose metabolism.

The elevation of serum uric acid depends on insulin resistance but not fasting plasma glucose in hyperuricaemia.

OBJECTIVES: The association between serum uric acid (SUA) and fasting plasma glucose (FPG) has not been fully outlined, in particular in hyperuricaemic population. This study aimed to address this issue, along with the exploration of the role of insulin resistance that was assessed by triglyceride-and-glucose (TyG) index. METHODS: A total of 16,297 participants without known diabetes from the SENSIBLE and SENSIBLE-Addition studies were included in the present analysis. Hyperuricaemia was defined as SUA ≥6 mg/dL. Generalised addictive model was applied to establish the relationship of SUA with FPG, and mediation analysis was performed to assess how insulin resistance affected the relationship. RESULTS: SUA showed an inverted U-shaped association with FPG, with the turning point of FPG at 6.1 mmol/L and 7.5 mmol/L in normouricaemic and hyperuricaemic participants, respectively. However, the significant relationship between SUA and FPG disappeared in hyperuricaemic participants (form B=3.3, 95% CI: 0.6-5.9, p=0.016 to B= -0.2, 95% CI: -3.1-2.7, p=0.894), and attenuated in normouricaemic participants (from B=9.8, 95% CI: 8.0-11.7, p<0.001 to B=7.3, 95% CI: 5.3-9.2, p<0.001) after controlling for TyG index. In the ascending segment, the relationship between SUA and FPG was partially mediated by TyG index in normouricaemic participants, but fully in hyperuricaemic participants. CONCLUSIONS: SUA had an inverted U-shaped relationship with FPG, and their positive relationship was fully mediated by insulin resistance in participants with hyperuricaemia but not those without.

Henagliflozin monotherapy in patients with type 2 diabetes inadequately controlled on diet and exercise: A randomized, double-blind, placebo-controlled, phase 3 trial.

AIM: To evaluate henagliflozin, a novel sodium-glucose co-transporter-2 inhibitor, as monotherapy in patients with type 2 diabetes and inadequate glycaemic control with diet and exercise. MATERIALS AND METHODS: This multicentre trial included a 24-week, randomized, double-blind, placebo-controlled period, followed by a 28-week extension period. Four hundred and sixty-eight patients with an HbA1c of 7.0%-10.5% were randomly assigned (1:1:1) to receive once-daily placebo, or 5 or 10 mg henagliflozin. After 24 weeks, patients on placebo were switched to 5 or 10 mg henagliflozin, and patients on henagliflozin maintained the initial therapy. The primary endpoint was the change in HbA1c from baseline after 24 weeks. RESULTS: At Week 24, the placebo-adjusted least squares (LS) mean changes from baseline in HbA1c were -0.91% (95% CI: -1.11% to -0.72%; P < .001) and -0.94% (-1.13% to -0.75%; P < .001) with henagliflozin 5 and 10 mg, respectively; the placebo-adjusted LS mean changes were -1.3 (-1.8 to -0.9) and -1.5 (-2.0 to -1.1) kg in body weight, and -5.1 (-7.2 to -3.0) and -4.4 (-6.5 to -2.3) mmHg in systolic blood pressure (all P < .05). The trends of these improvements were sustained for an additional 28 weeks. Adverse events occurred in 81.0%, 78.9% and 78.9% of patients in the placebo, henagliflozin 5 and 10 mg groups, respectively. No diabetic ketoacidosis or major episodes of hypoglycaemia occurred. CONCLUSIONS: Henagliflozin 5 mg and 10 mg as monotherapy provided effective glycaemic control, reduced body weight and blood pressure, and was generally well tolerated.

Endovascular Celiac Denervation for Glycemic Control in Patients with Type 2 Diabetes Mellitus.

PURPOSE: To investigate the safety and efficacy of catheter-based endovascular denervation (EDN) at the celiac artery and abdominal aorta around the celiac artery on glycemic control in patients with type 2 diabetes mellitus (T2DM). MATERIALS AND METHODS: With a novel catheter system, EDN was conducted at the celiac artery along with the abdominal aorta around the celiac artery in patients with T2DM whose glycosylated hemoglobin (HbA1c) level was >7.5%. The primary outcome was HbA1c level at 6 months. Other outcomes included safety, oral glucose tolerance test, homeostasis model assessment of insulin resistance (HOMA-IR), fasting plasma glucose (FPG) level, 2-hour postprandial plasma glucose (2hPG) level, and C-peptide test. RESULTS: A total of 11 subjects were included for analysis. The technical success was 100%, and no severe treatment-related adverse events or major complications were observed. Both HbA1c level and HOMA-IR were significantly reduced at 6 months (9.9% vs 8.0%, P = .005; 13.3 vs 6.0, P = .016). Decreases in FPG and 2hPG levels were observed (227.2 vs 181.8 mg/dL, P < .001; 322.2 vs 205.2 mg/dL, P = .001). The C-peptide test indicated improved ß-cell function (area under the curve, 0.23 vs 0.28 pmol/mL, P = .046). A reduction of daily insulin injection (P = .02) and improvement of liver function (alanine aminotransferase, P = .014; γ-glutamyl transpeptidase, P = .021) were also observed. CONCLUSIONS: EDN in the celiac artery and abdominal aorta around the celiac artery elicited a clinically significant improvement in glycemic control and insulin resistance in patients with T2DM, with good tolerability as demonstrated by 6-month follow-up.

Nonesterified free fatty acids enhance the inflammatory response in renal tubules by inducing extracellular ATP release.

In proteinuric renal diseases, excessive plasma nonesterified free fatty acids bound to albumin can leak across damaged glomeruli to be reabsorbed by renal proximal tubular cells and cause inflammatory tubular cells damage by as yet unknown mechanisms. The present study was designed to investigate these mechanisms induced by palmitic acid (PA; one of the nonesterified free fatty acids) overload. Our results show that excess PA stimulates ATP release through the pannexin 1 channel in human renal tubule epithelial cells (HK-2), increasing extracellular ATP concentration approximately threefold compared with control. The ATP release is dependent on caspase-3/7 activation induced by mitochondrial reactive oxygen species. Furthermore, extracellular ATP aggravates PA-induced monocyte chemoattractant protein-1 secretion and monocyte infiltration of tubular cells, enlarging the inflammatory response in both macrophages and HK-2 cells via the purinergic P2X7 receptor-mammalian target of rapamycin-forkhead box O1-thioredoxin-interacting protein/NOD-like receptor protein 3 inflammasome pathway. Hence, PA increases mitochondrial reactive oxygen species-induced ATP release and inflammatory stress, which cause a "first hit," while ATP itself is a "second hit" in amplifying the renal tubular inflammatory response. Thus, inhibition of ATP release or the purinergic P2X7 receptor may be an approach to reduce renal inflammation and improve renal function.

Role of endogenous glucagon-like peptide-1 enhanced by vildagliptin in the glycaemic and energy expenditure responses to intraduodenal fat infusion in type 2 diabetes.

AIM: To evaluate the effects of the dipeptidyl peptidase-4 (DPP-4) inhibitor vildagliptin on glycaemic and energy expenditure responses during intraduodenal fat infusion, as well as the contribution of endogenous glucagon-like peptide-1 (GLP-1) signalling, in people with type 2 diabetes (T2DM). METHODS: A total of 15 people with T2DM managed by diet and/or metformin (glycated haemoglobin 49.3 ± 2.1 mmol/mol) were studied on three occasions (two with vildagliptin and one with placebo) in a double-blind, randomized, crossover fashion. On each day, vildagliptin 50 mg or placebo was given orally, followed by intravenous exendin (9-39) 600 pmol/kg/min, on one of the two vildagliptin treatment days, or 0.9% saline over 180 minutes. At between 0 and 120 minutes, a fat emulsion was infused intraduodenally at 2 kcal/min. Energy expenditure, plasma glucose and glucose-regulatory hormones were evaluated. RESULTS: Intraduodenal fat increased plasma GLP-1 and glucose-dependent insulinotropic polypeptide (GIP), insulin and glucagon, and energy expenditure, and decreased plasma glucose (all P < 0.05). On the two intravenous saline days, plasma glucose and glucagon were lower, plasma intact GLP-1 was higher (all P < 0.05), and energy expenditure tended to be lower after vildagliptin (P = 0.08) than placebo. On the two vildagliptin days, plasma glucose, glucagon and GLP-1 (both total and intact), and energy expenditure were higher during intravenous exendin (9-39) than saline (all P < 0.05). CONCLUSIONS: In well-controlled T2DM during intraduodenal fat infusion, vildagliptin lowered plasma glucose and glucagon, and tended to decrease energy expenditure, effects that were mediated by endogenous GLP-1.

Tea consumption and risk of diabetes in the Chinese population: a multi-centre, cross-sectional study.

The aim of the present study was to explore the influence of tea consumption on diabetes mellitus in the Chinese population. This multi-centre, cross-sectional study was conducted in eight sites from south, east, north, west and middle regions in China by enrolling 12 017 subjects aged 20-70 years. Socio-demographic and general information was collected by a standardised questionnaire. A standard procedure was used to measure anthropometric characteristics and to obtain blood samples. The diagnosis of diabetes was determined using a standard 75-g oral glucose tolerance test. In the final analysis, 10 825 participants were included and multiple logistic models and interaction effect analysis were applied for assessing the association between tea drinking with diabetes. Compared with non-tea drinkers, the multivariable-adjusted OR for newly diagnosed diabetes were 0·80 (95 % CI 0·67, 0·97), 0·88 (95 % CI 0·71, 1·09) and 0·86 (95 % CI 0·67, 1·11) for daily tea drinkers, occasional tea drinkers and seldom tea drinkers, respectively. Furthermore, drinking tea daily was related to decreased risk of diabetes in females by 32 %, elderly (>45 years) by 24 % and obese (BMI > 30 kg/m2) by 34 %. Moreover, drinking dark tea was associated with reduced risk of diabetes by 45 % (OR 0·55; 95 % CI 0·42, 0·72; P < 0·01). The results imply that drinking tea daily was negatively related to risk of diabetes in female, elderly and obese people. In addition, drinking dark tea was associated with decreased risk of type 2 diabetes mellitus.

A modified in vitro tool for isolation and characterization of rat quiescent islet stellate cells.

BACKGROUND: Islet stellate cells (ISCs) play a critical role in islet fibrosis, contributing to the progression of pancreatic diseases. Previous studies have focused on fibrosis-associated activated ISCs obtained by standard islet explant techniques. However, in vitro models of quiescent ISCs (qISCs) are lacking. This study aims to develop a method to isolate qISCs and analyze their phenotype during activation. METHODS: Immunofluorescence staining was applied to localize ISCs in normal human, rat, and mouse islets. qISCs were isolated from rat islets using density gradient centrifugation (DGC) method. qRT-PCR, immunoblotting, proliferation, and migration assays were employed for their characterization. RESULTS: Desmin-positive ISCs were detected in normal human, rat, and mouse islets. Freshly isolated qISCs, obtained by density gradient centrifugation, displayed a polygonal appearance with refringent cytoplasmic lipid droplets and expressed transcriptional markers indicating a low activation/quiescent state. With increasing culture time, the marker expression pattern changed, reflecting ISC activation. qISCs contained more lipid droplets and exhibited lower proliferation and migration abilities compared to spindle-shaped ISCs obtained by traditional explant techniques. CONCLUSIONS: This study describes a new method for efficient isolation of qISCs from rat islets, representing a useful in vitro tool to study the biology of ISCs in more physiological conditions.

Lipotoxicity reduces ß cell survival through islet stellate cell activation regulated by lipid metabolism-related molecules.

BACKGROUND: Islet stellate cells (ISCs) activation is mainly associated with islet fibrosis, which contributes to the progression of type 2 diabetes. However, the molecular mechanism underlying this process is not fully understood. METHODS: In order to investigate this process the current study examined ectopic fat accumulation in rats with high-fat diet (HFD) induced obesity. Levels of lipotoxicity-induced ISC activation and islet function were assessed via intraperitoneal glucose and insulin tolerance tests, and immunohistochemistry. The expression of lipid metabolism- and ISC activation-related markers was evaluated in cultured ISCs treated with palmitic acid (PA) using quantitative PCR and western blotting. We also overexpressed sterol regulatory element-binding protein (SREBP)-1c in ISCs by lentiviral transduction, and assessed the effects on insulin release in co-cultures with isolated rat islets. RESULTS: HFD increased body weight and ectopic fat accumulation in pancreatic islets. Lipotoxicity caused progressive glucose intolerance and insulin resistance, upregulated α-smooth muscle actin, and stimulated the secretion of extracellular matrix. Lipotoxicity reduced the expression of lipid metabolism-related molecules in ISCs treated with PA, especially SREBP-1c. Overexpression of SREBP-1c in ISCs improved islet viability and insulin secretion in co-cultures. CONCLUCIONS: These results indicate that lipotoxicity-induced ISC activation alters islet function via regulation of lipid metabolism, suggesting that therapeutic strategies targeting activated ISC may be an effective treatment for prevention of ISC activation-associated islet dysfunction.

Protective effects of Clec11a in islets against lipotoxicity via modulation of proliferation and lipid metabolism in mice.

The lipotoxicity is considered as one of the risk for diabetes. Here we report C-type lectin domain family 11, member A (Clec11a) as a new regulator in islet playing a protective role in lipotoxicity induced dysfunction. Islet transcriptome sequencing was performed using the high-fat diet induced obesity (DIO) mice model. We found a significant decrease of Clec11a expression in islets of DIO mice compared to normal control mice, which was further confirmed by real-time PCR. Immunostaining demonstrated the localization of the Clec11a protein in mouse islets. Administration of recombinant human Clec11a (rClec11a) protein promoted the proliferation of islet cells and rescued the inhibition of fatty acid on cell proliferation, which involved the activation of Erk signaling pathway. We also found that the rClec11a altered the expression of genes involved in lipid metabolism.

Association Between Cardiorespiratory Fitness and Risk of Heart Failure: A Meta-Analysis.

BACKGROUND: Evidence emerges that cardiorespiratory fitness (CRF) might be implicated in the development of heart failure (HF). This meta-analysis aimed to quantify the association between CRF exposed at baseline and HF risk with dose-response analysis and to assess whether CRF changes over time are correlated with alterations in HF risk. METHODS AND RESULTS: Cohort studies that assessed the association between CRF and risk of HF in subjects without baseline HF were included. Study-specific multivariate-adjusted relative risks (RRs) with 95% confidence intervals (CIs) were pooled using a random-effects model. Ten studies from 8 articles were included, enrolling 8987 incident HF cases from 154,598 participants. The RR of HF per 1-metabolic equivalent (MET) higher CRF at baseline was 0.82 (95% CI 0.80-0.84) in the overall population. The RRs were similar in men (0.82, 95% CI 0.80-0.85) and women (0.81, 95% CI 0.78-0.84), and remained minorly changed in patients with existing diabetes, hypertension, or cardiovascular disease at entry. No evidence of a nonlinear relationship between CRF at baseline and risk of HF was observed (Pnonlinearity = .18). The RR of HF per 1-MET increase in CRF over time was 0.79 (95% CI 0.67-0.93), and the measurement of CRF provided incremental value to the prediction of HF beyond conventional models. CONCLUSIONS: High or increased CRF resulted in reduced risk of HF in a dose-dependent manner, supporting the necessity to increase CRF to prevent HF in clinical practice.

Use of capillary glucose combined with other non-laboratory examinations to screen for diabetes and prediabetes.

AIM: To evaluate the value and feasibility of capillary glucose assessment, combined with other non-laboratory measures, in screening for diabetes and prediabetes in the community. METHODS: In this cross-sectional study, we assessed fasting capillary glucose, fasting plasma glucose, and both capillary glucose and plasma glucose values after 2-h oral glucose tolerance tests in a total of 3736 samples. We determined the optimal threshold of capillary glucose using receiver-operating characteristic curve analysis. The effect of screening methods using capillary glucose combined with other variables, such as age, BMI and waist circumference, was assessed according to area under the receiver-operating characteristic curve. RESULTS: There was a strong positive correlation between capillary glucose and venous plasma glucose. The area under the curve for the model using fasting capillary glucose to screen for impaired fasting glucose was 0.722, while that for the model using capillary glucose after a 2-h oral glucose tolerance test to screen for impaired glucose tolerance was 0.916. The area under the curve for the model using fasting capillary glucose to screen for diabetes was 0.835, while that for the model using 2-h oral glucose tolerance test capillary glucose was 0.912. The area under the curve for the model using fasting capillary glucose + 2-h oral glucose tolerance test capillary glucose to screen for diabetes was 0.945. The discriminatory capability of models using capillary glucose was somewhat improved by adding non-laboratory variables. CONCLUSIONS: Capillary glucose could be an alternative for screening for diabetes and prediabetes, especially in low-resource areas.