Tophi and carotid atherosclerosis in gout patients: Role of insulin resistance

BACKGROUND AND AIM

Gout and cardiovascular disease are closely related, but the mechanism linking them is still unknown. Gout may affect the insulin signaling pathway inducing insulin resistance (IR). The study aims to evaluate the association between tophi and carotid atherosclerosis, considering the potential role of IR.

METHODS AND RESULTS

A total of 595 patients with gout aged 18 to 80 were enrolled in this study. Carotid intima-media thickness, plaques and tophi were evaluated by B-mode ultrasonography. IR was assessed by the HOMA index (hepatic IR) and Gutt index (peripheral IR). Multivariable logistic regression and interaction analysis were used to examine the association between tophi and IR and its impact on carotid atherosclerosis. Among these participants, the average age was 55.4 (±12.54) years, and 94.6 % were male. Tophi were associated with increased odds of carotid atherosclerosis and burden after adjustment for confounders (P < 0.05). Tophi and IR synergically interacted for inducing carotid atherosclerosis. The interaction between peripheral IR with tophi was more pronounced than hepatic IR with tophi.

CONCLUSIONS

Tophi were independently associated with carotid atherosclerosis risk. IR mediated a significant amount of the effect of tophi on the development of carotid atherosclerosis. Peripheral IR probably plays a more important role than hepatic IR does.

Sinensetin ameliorates high glucose-induced diabetic nephropathy via enhancing autophagy in vitro and in vivo

Diabetic nephropathy (DN) affects around 40% of people with diabetes, the final outcome of which is end-stage renal disease. The deficiency of autophagy and excessive oxidative stress have been found to participate in the pathogenesis of DN. Sinensetin (SIN) has been proven to have strong antioxidant capability. However, the effect of SIN on DN has not been studied. We examined the effect of SIN on cell viability and autophagy in the podocyte cell line, MPC5 cells, treated with high glucose (HG). For in vivo studies, DN mice models were established by intraperitoneal injected with streptozotocin (40 mg/kg) for 5 consecutive days and fed with a 60% high-fat diet, and SIN was given (10, 20, and 40 mg/kg) for 8 weeks via intraperitoneal injection. The results showed that SIN could protect MPC5 cells against HG-induced damage and significantly improve the renal function of DN mice. Moreover, SIN remarkably restored the autophagy activity of MPC5 cells which was inhibited under HG conditions. Consistent with this, SIN efficiently improved autophagy in the kidney tissue of DN mice. In brief, our findings demonstrated the protective effect of SIN on DN via restoring the autophagic function, which might provide a basis for drug development.

The role of C-peptide in diabetes and its complications: an updated review

Worldwide, diabetes and its complications have seriously affected people's quality of life and become a serious public health problem. C-peptide is not only an indicator of pancreatic β-cell function, but also a biologically active peptide that can bind to cell membrane surface signaling molecules and activate downstream signaling pathways to play antioxidant, anti-apoptotic and inflammatory roles, or regulate cellular transcription through internalization. It is complex how C-peptide is related to diabetic complications. Both deficiencies and overproduction can lead to complications, but their mechanisms of action may be different. C-peptide replacement therapy has shown beneficial effects on diabetic complications in animal models when C-peptide is deficient, but results from clinical trials have been unsatisfactory. The complex pattern of the relationship between C-peptide and diabetic chronic complications has not yet been fully understood. Future basic and clinical studies of C-peptide replacement therapies will need to focus on baseline levels of C-peptide in addition to more attention also needs to be paid to post-treatment C-peptide levels to explore the optimal range of fasting C-peptide and postprandial C-peptide maintenance.

Renoprotective Effect of Isoorientin in Diabetic Nephropathy via Activating Autophagy and Inhibiting the PI3K-AKT-TSC2-mTOR Pathway

Diabetic nephropathy (DN) is one of the most serious complications of diabetes and the most common cause of death. The autophagy of podocytes plays an important role in the pathogenesis of DN. Here, through screening the constituent compounds of practical and useful Chinese herbal formulas, we identified that isoorientin (ISO) strongly promoted the autophagy of podocytes and could effectively protect podocytes from high glucose (HG)-induced injury. ISO significantly improved autophagic clearance of damaged mitochondria under HG conditions. Through a proteomics-based approach, we identified that ISO could reverse the excessive phosphorylation of TSC2 S939 under HG conditions and stimulate autophagy through inhibition of the PI3K-AKT-TSC2-mTOR pathway. Furthermore, ISO was predicted to bind to the SH2 domain of PI3Kp85[Formula: see text], which is crucial for the recruitment and activation of PI3K. The protective effect of ISO and its effects on autophagy and particularly on mitophagy were further proved using a DN mice model. To summarize, our study identified the protective effects of ISO against DN and demonstrated that ISO was a strong activator of autophagy, which could provide a basis for drug development.

Obesity is associated with impaired postprandial pancreatic polypeptide secretion

Objective

This study aims to compare the levels of serum pancreatic polypeptide (PP), insulin (INS), C-peptide (C-P), and glucagon (GCG) before and after glucose stimulation in type 2 diabetes mellitus (T2DM) patients with different body mass indexes (BMI), analyze the relevant factors associated with PP secretion, and further investigate the role of PP in the development of obesity and diabetes.

Methods

Data were collected from 83 patients from the hospital. The subjects were divided into normal-weight group, overweight group, and obese group according to their BMI. All subjects were tested with the standard bread meal test (SBMT). PP and relevant parameters were measured, and the area under the curve (AUC) was calculated after 120 min of SBMT. AUC_pp (AUC of PP) was used as the dependent variable, and the potential influencing factors were used as independent variables for multiple linear regression analysis.

Results

The obese and overweight groups had significantly lower PP secretion than the normal-weight group (485.95 pg·h/ml, 95% CI 76.16-895.74, p = 0.021; 664.61 pg·h/ml, 95% CI 285.46-1043.77, p = 0.001) at 60 min postprandial. PP secretion in the obese and overweight groups was also significantly lower than that in the normal-weight group (520.07 pg·h/ml, 95% CI 186.58-853.56, p = 0.003; 467.62 pg·h/ml, 95% CI 159.06-776.18, p = 0.003) at 120 min postprandial. AUC_pp was negatively associated with BMI (r = -0.260, p = 0.017) and positively associated with AUC_GCG (r = 0.501, p< 0.001). Multiple linear regression analysis showed that there was a linear correlation between AUC_GCG, BMI, and AUC_pp (p< 0.001, p = 0.008). The regression equation was calculated as follows: AUC_pp = 1772.255-39.65 × BMI + 0.957 × AUC_GCG (R^2 = 54.1%, p< 0.001).

Conclusion

Compared with normal-weight subjects, overweight and obese subjects had impaired PP secretion after glucose stimulation. In T2DM patients, PP secretion was mainly affected by BMI and GCG.

Clinical trial registry

The Ethics Committee of the Affiliated Hospital of Qingdao University.

Clinical trial registration

http://www.chictr.org.cn, identifier ChiCTR2100047486.

Endoplasmic reticulum stress in the adipose tissue and monocyte chemoattractant protein-1 are involved in tacrolimus-induced diabetes mellitus

Tacrolimus is an independent risk factor for new-onset diabetes after transplantation (NODAT). This study aimed to identify the mechanisms underlying tacrolimus-induced NODAT. About 80 kidney-transplant patients receiving tacrolimus were divided into NODAT and non-NODAT groups after 1 year. Binary logistic regression was used to identify risk factors for NODAT. Insulin resistance indices were estimated using the homeostasis model assessment. The blood levels of 13 adipocytokines were measured 1 week after transplantation. A tacrolimus-induced diabetes mouse model was used to reveal the underlying mechanisms. The cumulative NODAT incidence was 12.7% at 1 year (median, 6 months; range, 3-12 months). Tacrolimus trough levels ≥10 ng/mL during the first 3 months (odds ratio: 2.54, p = .012) were related to NODAT. Insulin resistance indices were higher in NODAT patients than in non-NODAT patients at 3, 6, and 12 months. Monocyte chemoattractant protein (MCP)-1 was overexpressed in blood in NODAT patients. In the animal experiments, postprandial blood glucose and insulin levels, insulin pathway protein levels in adipose tissue, MCP-1 expression in blood and adipose tissue, and number of macrophages in adipose tissue were markedly higher in tacrolimus-treated mice than in control mice, and these increases were dose-dependent. The expression of endoplasmic reticulum (ER) stress proteins in adipose tissue was increased in a tacrolimus dose-dependent manner. In conclusion, tacrolimus-induced insulin resistance. Tacrolimus trough levels ≥10 ng/mL during the first 3 postoperative months were an independent risk factor for NODAT. ER stress and MCP-1 underlie tacrolimus-induced diabetes.

The risk of nonalcoholic fatty liver disease in gout patients with frequent flares: a retrospective cohort study

OBJECTIVE

Nonalcoholic fatty liver disease (NAFLD) is a common chronic disease that is related to high serum uric acid; however, the association between the frequency of gout flares and NAFLD risk remains unclear. This study aimed to investigate whether frequent gout flares were associated with incident NAFLD and analyze the interaction of frequency of gout flares and Adipo-IR on NAFLD in the gout Chinese population.

METHODS

A total of 350 cases of gout patients were enrolled in this retrospective cohort study. Cox proportional hazard regression analyses were performed to determine the association between frequent gout flares and NAFLD during follow-up and analyze the interaction of frequency of gout flares and Adipo-IR on NAFLD. Receiver operating curves (ROC) were plotted to explore the diagnostic value of frequent gout flares and Adipo-IR on the occurrence of NAFLD.

RESULTS

NAFLD developed in 78 participants (22.3%) during follow-up. Logistic regression showed that Adipo-IR was an independent factor associated with frequent gout flares risk. The multivariate Cox regression analysis revealed that frequent gout flares and Adipo-IR were associated with NAFLD risk (HR: 7.88, 95% CI: 2.11-29.48, p < 0.01; HR: 1.058, 95% CI: 1.01-1.2, p < 0.05). And ROC showed that both of them had a great discriminant ability to diagnose NAFLD.

CONCLUSIONS

Our data showed an independent association between the frequency of gout flares or Adipo-IR and incident NAFLD. Frequent gout flares and elevated Adipo-IR had a good predictive capability towards NAFLD development and played a synergistic role in the development of NAFLD.

KEY POINTS

• Frequent gout flares and elevated Adipo-IR had a good diagnostic capability towards NAFLD development. • Frequent gout flares and Adipo-IR played a synergistic role in the development of NAFLD.

hUCMSCs carrying exenatide prevent T1DM by improving intestinal microflora composition and islet tissue damage repair

BACKGROUND

Exenatide is a stable analogue of glucagon-like peptide 1 that can reduce postprandial hyperglycemia and has been utilized as adjunctive therapy for type 1 diabetes mellitus (T1DM). The human umbilical cord is a rich source of MSCs, and human umbilical cord mesenchymal stem cells (hUCMSCs) also show potential to enhance insulin secretion. Here, we aimed to explore the effects of hUCMSCs carrying exenatide in T1DM and further identify the possible mechanisms involved.

METHODS

hUCMSCs were isolated from human umbilical cord tissues, identified, and transduced with recombinant lentivirus carrying exenatide to obtain exenatide-carrying hUCMSCs (hUCMSCs@Ex-4).

RESULTS

The results showed that hUCMSCs@Ex-4 restored the blood glucose levels and body weight of NOD mice, and repressed immune cell infiltration and islet tissue changes. Additionally, in T1DM mice, treatment with hUCMSCs@Ex-4 reduced the blood glucose levels and promoted repair of islet tissue damage. Moreover, hUCMSCs@Ex-4 attenuated renal tissue lesions in T1DM mice. Applying bioinformatic analysis, the effects of hUCMSCs@Ex-4 were suggested to correlate with decreased abundance of pro-inflammatory intestinal bacteria and increased abundance of anti-inflammatory intestinal bacteria.

CONCLUSION

Overall, the study indicated that hUCMSCs carrying exenatide might improve beneficial intestinal microflora abundance and promote islet tissue damage repair, thereby alleviating T1DM.

Video-assisted superior mediastinal lymphadenectomy for papillary thyroid cancer: a case report

Superior mediastinal lymph node metastases in papillary thyroid cancer are uncommon. The clinical characteristics and surgical strategy of superior mediastinal lymph node metastases remain unclear. Superior mediastinal lymphadenectomy can be accomplished either by a transcervical or transsternal approach. Transsternal approach for superior mediastinal lymphadenectomy can cause great damage; transcervical approach sometimes results in inadequate exposure. Here we report our experience of a papillary thyroid cancer patient with superior mediastinal lymph node metastases who underwent video-assisted superior mediastinal lymphadenectomy. A 49-year-old woman diagnosed with papillary thyroid cancer in left thyroid underwent unilateral lobectomy and ipsilateral central and lateral node dissection in the local hospital 4 years ago. Currently lymph node metastases were found in mediastinum and the right neck, some of which were adjacent to the right innominate vein. Unilateral lobectomy, ipsilateral central and lateral node dissection, and video-assisted superior mediastinal lymphadenectomy were successfully performed by transcervical approach. Subsequently, the patient received thyroxine suppression therapy and adjuvant radioiodine treatment. Video-assisted superior mediastinal lymphadenectomy, providing adequate exposure for a complete superior mediastinal lymphadenectomy, is proved to be safe and feasible.

The Negative Association Between NAFLD Severity and CKD in a Non-Diabetic Gouty Population

Nonalcoholic fatty liver disease (NAFLD) and chronic kidney disease (CKD) share common pathogenic mechanisms and risk factors. We aim to evaluate the association between NAFLD and CKD in a non-diabetic gouty population. The retrospective cross sectional study was performed on 1049 non-diabetic gouty participants, who were hospitalized between 2014 and 2020, across 4 districts in Shandong, China. Demographic and clinical characteristics of the study population were collected. The odds ratios (OR) and corresponding 95% confidence intervals (CI) about the NAFLD severity determined by ultrasonography were obtained by multiple logistic regression analysis. An unexpectedly inverse relationship was found between NAFLD severity and the risk of CKD in people with gout. Multivariate logistic regression analysis demonstrated that a higher degree of NAFLD severity is independently associated with a lower risk of CKD in people with gout, after adjusted for age, sex, smoking, gout duration, and metabolic risk factors including obesity, hypertension, hyperglycemia, hyperuricemia, and dyslipidemia, with OR 0.392 (95% CI 0.248-0.619, p<0.001), 0.379 (95% CI 0.233-0.616, p<0.001) and 0.148 (95% CI 0.043-0.512, p=0.003) in participants with mild, moderate, and severe NAFLD, respectively, compared to those without NAFLD. We also observed a weakened association of serum uric acid (SUA) with metabolic risk factors and NAFLD under circumstances of CKD in people with gout (r=-0.054, p=0.466). In conclusion, the presence and severity of NAFLD were negatively associated with the risk of CKD in the non-diabetic gouty population.

Impaired glucose tolerance is associated with enhanced postprandial pancreatic polypeptide secretion

BACKGROUND

The purpose of this study is to compare serum pancreatic polypeptide (PP), insulin, C-peptide, and glucagon in different glucose tolerance stages; analyze the influencing factors of PP secretion; and further explore the role of PP in the pathogenesis of diabetes mellitus.

METHODS

Data were collected from 100 subjects from hospital. According to the results of oral glucose tolerance test (OGTT), the subjects were divided into a normal glucose tolerance (NGT) group, an impaired glucose regulation (IGR) group, and a newly diagnosed type 2 diabetes mellitus (T2DM) group. PP and the related parameters were measured, and the area under the curve (AUC) 120 min after OGTT was calculated. AUC_pp (AUC of PP) was used as the dependent variable and the potentially influencing factors were used as the independent variable for multiple linear regression analysis.

RESULTS

Postprandial 60 min PP in the IGR group was higher than those in the NGT group (2973.80 [±547.49] pg·h/mL vs 2663.55 [±594.89] pg·h/mL, p < 0.05). AUC_pp was significantly higher in the IGR group (428.76 pg·h/mL, 95% confidence interval [CI] [41.06 -816.46], p = 0.031) and newly diagnosed T2DM group (404.35 pg·h/mL, 95% CI [5.37-803.33], p = 0.047) than in the NGT group. AUC_pp was negatively correlated with body mass index (BMI) (r = -0.235, p = 0.038) and positively correlated with postprandial 60 min blood glucose (r = 0.370, p = 0.001) and AUC_bg (AUC of blood glucose) (r = 0.323, p = 0.007). Multiple linear regression analysis indicated that there was a linear correlation between BMI, AUC_bg , and AUC_pp (p = 0.004, p = 0.001), and the regression equation was calculated as: AUC_pp  = 6592.272 + 86.275 × AUC_bg -95.291 × BMI (R²  = 12.7%, p < 0.05).

CONCLUSIONS

Compared with NGT subjects, IGR and T2DM patients have an enhanced postprandial PP secretion. In T2DMs, the secretion of PP is mainly affected by BMI and blood glucose.

Resveratrol Enhances Wound Healing in Type 1 Diabetes Mellitus by Promoting the Expression of Extracellular Vesicle-Carried MicroRNA-129 Derived from Mesenchymal Stem Cells

Recent studies have shown the promotive effect of resveratrol on wound healing. This study aims to explore the underlying molecular mechanism of resveratrol in type 1 diabetes mellitus (T1DM) through microRNA (miR)-129-containing extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) based on in silico analysis. The rat model of T1DM was established by intraperitoneal injection of sodium citrate containing streptozotocin, and the wound was made around the deep fascia. Rat MSCs were isolated and treated with resveratrol (SRT501), and the corresponding EVs (SRT501-EVs) were isolated, where the expression of miR-129 was determined. By performing function experiments, the effect of SRT501-EVs and miR-129 on the biological functions of human umbilical vein endothelial cells (HUVECs) was determined. Finally, the binding relationship between miR-129 and tumor necrosis factor receptor-associated factor 6 (TRAF6) was also determined by the dual-luciferase reporter gene assay. miR-129 was shown as a candidate related to both resveratrol and wound healing in T1DM. SRT501-EVs promoted the skin wound healing of T1DM rats and also further improved the proliferative, migratory, and tube formation potentials of HUVECs. Resveratrol inhibited the expression of TRAF6 in HUVECs stimulated by MSC-conditioned medium and promoted the transfer of miR-129 via EVs, while TRAF6 was confirmed as a target gene of miR-129. Furthermore, inhibition of miR-129 attenuated the proangiogenic effect of resveratrol on HUVECs. Resveratrol exerts promotive role in wound healing in T1DM through downregulation of TRAF6 via MSC-EV-carried miR-129, suggesting a regulatory network involved in the wound healing process in T1DM.

Establishment and validation of a clinical model for predicting diabetic ketosis in patients with type 2 diabetes mellitus

BACKGROUND

Diabetic ketosis (DK) is one of the leading causes of hospitalization among patients with diabetes. Failure to recognize DK symptoms may lead to complications, such as diabetic ketoacidosis, severe neurological morbidity, and death.

PURPOSE

This study aimed to develop and validate a model to predict DK in patients with type 2 diabetes mellitus (T2DM) based on both clinical and biochemical characteristics.

METHODS

A cross-sectional study was conducted by evaluating the records of 3,126 patients with T2DM, with or without DK, at The Affiliated Hospital of Qingdao University from January 2015 to May 2022. The patients were divided randomly into the model development (70%) or validation (30%) cohorts. A risk prediction model was constructed using a stepwise logistic regression analysis to assess the risk of DK in the model development cohort. This model was then validated using a second cohort of patients.

RESULTS

The stepwise logistic regression analysis showed that the independent risk factors for DK in patients with T2DM were the 2-h postprandial C-peptide (2hCP) level, age, free fatty acids (FFA), and HbA1c. Based on these factors, we constructed a risk prediction model. The final risk prediction model was L= (0.472a - 0.202b - 0.078c + 0.005d - 4.299), where a = HbA1c level, b = 2hCP, c = age, and d = FFA. The area under the curve (AUC) was 0.917 (95% confidence interval [CI], 0.899-0.934; p<0.001). The discriminatory ability of the model was equivalent in the validation cohort (AUC, 0.922; 95% CI, 0.898-0.946; p<0.001).

CONCLUSION

This study identified independent risk factors for DK in patients with T2DM and constructed a prediction model based on these factors. The present findings provide an easy-to-use, easily interpretable, and accessible clinical tool for predicting DK in patients with T2DM.

The Role of Slit-2 in Gestational Diabetes Mellitus and Its Effect on Pregnancy Outcome

BACKGROUND

Slit guidance ligand 2 (Slit-2), as a member of the Slit family, can regulate the inflammatory response and glucose metabolism. The purpose of this study was to explore the expression of Slit-2 in maternal peripheral blood and neonatal cord blood of gestational diabetes mellitus (GDM) patients and its potential importance in disease progression.

METHODS

This study included 57 healthy pregnant women and 61 GDM patients. The levels of Slit-2, C-reactive protein (CRP), monocyte chemoattractant protein-1 (MCP-1), C-peptide (C-P), galectin-3(Gal-3), HbA1c, fasting blood glucose (FBG) and fasting insulin (FINS) in maternal peripheral blood and neonatal cord blood were detected by ELISA. Spearman's rank correlation test was used to assess the association between peripheral Slit-2 and inflammatory indicators, insulin resistance, and pregnancy outcomes. Logistic regression analysis was used to analyze the risk factors of GDM.

RESULTS

Slit-2 levels in maternal peripheral blood and neonatal cord blood of the GDM patients were higher than those of the HC. Slit-2 levels in maternal peripheral blood and neonatal cord blood of the GDM patients were positively correlated with inflammatory factors CRP and MCP-1 levels. The level of Slit-2 in the maternal peripheral blood of the GDM patients was positively correlated with the level of homeostasis model assessment insulin resistance (HOMA-IR) and HbA1c in maternal peripheral blood, but was negatively correlated with the level of homeostasis model assessment -β (HOMA-β). We also found that the Slit-2 level in the maternal peripheral blood of the GDM patients was negatively correlated with neonatal blood glucose, positively correlated with neonatal weight and independent of neonatal total bilirubin.

CONCLUSION

Our study suggests that the abnormal increase in Slit-2 in GDM may be related to its pathogenesis, and it was correlated with neonatal blood glucose and weight in patients with GDM, suggesting that Slit-2 may be a potential biomarker of GDM.

MiR-223-3p and miR-22-3p inhibit monosodium urate-induced gouty inflammation by targeting NLRP3

BACKGROUND

MicroRNAs (miRNAs) have been shown to play a crucial role in inflammation regulation; however, their relationship with inflammation in acute gouty arthritis has not been fully elucidated. Herein, we conducted a study to explore the regulatory roles of miR-223-3p and miR-22-3p in gouty-associated inflammation.

METHODS

In vitro and in vivo experiments were conducted to examine the molecular mechanisms of miRNA regulation in gouty inflammation. Dual-luciferase reporter assay was used to verify the direct target of miR-223-3p and miR-22-3p.

RESULTS

We found that miR-223-3p and miR-22-3p interacted with the 3' untranslated region segment of NLRP3 (nucleotide-binding domain leucine-rich repeat [NLR] and pyrin domain containing receptor 3) and inhibited its expression. A decreased expression of miR-223-3p and miR-22-3p was observed in both mice air pouch synovium and phorbol myristrate acetate-treated THP-1 cells stimulated with monosodium urate (P < .05). Compared with the negative control group, NLRP3 expression at the transcript and protein level in miR-223-3p and miR-22-3p overexpression group significantly decreased after 6 hours of monosodium urate treatment in vivo and in vitro (P < .05). The results of the dual-luciferase reporter assay demonstrated that miR-223-3p and miR-22-3p directly targeted NLRP3.

CONCLUSION

The findings of the present study show that miR-223-3p and miR-22-3p can reduce the inflammatory effects of gout by inhibiting the expression of NLRP3.

Obesity and diabetes as high-risk factors for severe coronavirus disease 2019 (Covid-19)

The outbreak of the coronavirus disease 2019 (Covid-19) has become an evolving worldwide health crisis. With the rising prevalence of obesity and diabetes has come an increasing awareness of their impacts on infectious diseases, including increased risk for various infections, post-infection complications and mortality from critical infections. Although epidemiological and clinical characteristics of Covid-19 have been constantly reported, no article has systematically illustrated the role of obesity and diabetes in Covid-19, or how Covid-19 affects obesity and diabetes, or special treatment in these at-risk populations. Here, we present a synthesis of the recent advances in our understanding of the relationships between obesity, diabetes and Covid-19 along with the underlying mechanisms, and provide special treatment guidance for these at-risk populations.

Efficacy and safety of endothelin receptor antagonists in type 2 diabetic kidney disease: A systematic review and meta-analysis of randomized controlled trials

AIM

To analyse the efficacy and safety of endothelin receptor antagonists for people with diabetic kidney disease.

METHODS

Randomized controlled trials comparing endothelin receptor antagonists with placebo in people with diabetic kidney disease were identified through PubMed, Embase and the Cochrane Library. We used a random-effect model to calculate the mean difference or risk ratio with the 95% CI.

RESULTS

Seven studies with a total of 4730 participants were included. Overall, endothelin receptor antagonists significantly reduced albuminuria compared with placebo (standardized mean difference -0.48, 95% CI -0.64 to -0.33). Atrasentan, in particular, effectively reduced albuminuria (standardized mean difference -0.58, 95% CI -1.00 to -0.17) and the risk of composite renal endpoints (risk ratio 0.65; 95% CI 0.49 to 0.88), with insignificant change in the rate of congestive heart failure (risk ratio 1.40, 95% CI 0.76 to 2.56) and mortality (risk ratio 1.11, 95% CI 0.77 to 1.61). In contrast, although avosentan reduced albuminuria (standardized mean difference -0.47, 95% CI -0.57 to -0.36) and the risk of composite renal endpoints (risk ratio 0.63, 95% CI 0.42 to 0.94), it was associated with a significant increase in congestive heart failure risk (risk ratio 2.61, 95% CI 1.36 to 5.00) and an insignificant increase in mortality risk (risk ratio 1.50, 95% CI 0.81, 2.78). No significant change in efficacy or safety outcomes with bosentan was detected. Dose-response analysis indicated that 0.75 mg/day atrasentan is expected to be optimal for renoprotection, with maximal albuminuria reduction and minimal fluid retention events.

CONCLUSIONS

Among the endothelin receptor antagonists, atrasentan and avosentan, but not bosentan, are effective for renoprotection in people with diabetic kidney disease. Compared with other types and doses, atrasentan 0.75 mg/day is the most promising, with maximal albuminuria reduction and minimal fluid retention. Vigilant monitoring of congestive heart failure risk is needed in future clinical practice. (PROSPERO registration no. CRD42020169840).

Elevated circulating luteinizing hormone levels are associated with diabetic macroalbuminuria in Chinese men and postmenopausal women: A cross-sectional study

BACKGROUND

Associations between sex hormones and diabetic vascular complications have recently been studied, but the role luteinizing hormone (LH) plays in diabetic kidney disease (DKD) remains uncertain. We aimed to investigate the relationship of LH and DKD in Chinese men and postmenopausal women with type 2 diabetes mellitus (T2DM).

METHODS

Data were collected from 1775 T2DM men and postmenopausal women in hospital. The odds ratios (OR) and corresponding 95% confidence intervals (CI) in relation to LH quartiles were obtained by multiple logistic regression analysis.

RESULTS

LH levels were significantly higher in patients with macroalbuminuria than in those with microalbuminuria, but were not higher in patients with microalbuminuria than in those with normoalbuminuria. Consistently, LH in those with an estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73m² were significantly higher than in those with eGFR≥60 mL/min/1.73m² . The prevalence of macroalbuminuria was obviously increased for subjects of the fourth quartile of LH vs the first to third quartile (20.4% vs 6.2%, 8.0%, 12.2% in men; 25.3% vs 5.5%, 3.8%, 9.3% in postmenopausal women). Multivariate logistic regression demonstrated that subjects within the highest quartile of LH had higher odds of macroalbuminuria than those within the lowest quartile (OR 4.00, 95% CI, 1.87-8.55 for men; OR 9.62, 95% CI, 3.42-27.08 for postmenopausal women), independent of age, diabetes duration, or other metabolic factors. The area under the curve for detecting macroalbuminuria based on LH was 0.662 for men, and 0.767 for postmenopausal women.

CONCLUSION

High LH levels are positively associated with established DKD among Chinese men and postmenopausal women. Elevated LH may be a promising clinical factor for identifying established DKD.

The effects of adipose-derived mesenchymal stem cells combined with sodium selenite on Hashimoto's thyroiditis

Recent research found that sodium selenite (Na₂SeO₃) could ameliorate oxidative damage in patients with Hashimoto's thyroiditis (HT). Additionally, the effects of adipose-derived mesenchymal stem cells (AMSCs) in an animal model of HT were also reported. However, the effects of AMSCs combined with Na₂SeO₃ on HT are unknown. We investigated the combined effects of AMSCs and Na₂SeO₃ in a rat model of HT and the in vitro effect of Na₂SeO₃ on AMSCs using gene microarray analyses. In the HT rat model, the combination of AMSCs and Na₂SeO₃ restored thyroid tissue structure to that of normal controls and increased the levels of most antioxidant and inflammatory cytokines examined, but decreased the levels of interleukin 10 (IL-10) in HT thyroid tissues. At 0.5-20 µM, Na₂SeO₃ promoted AMSC growth and increased the levels of reduced glutathione and total antioxidant capacity in AMSCs (P<0.05). Na₂SeO₃ increased the levels of hepatocyte growth factor (HGF), transforming growth factor beta (TGF-β), and stem cell factor (SCF) in AMSC culture supernatants. The results of the gene microarray analyses showed that the expression levels of certain genes involved in mitosis, DNA replication and repair, ubiquitination, synthesis and metabolism, and mitochondrial transport changed in response to Na₂SeO₃ treatment. In conclusion, the combination of AMSCs and Na₂SeO₃ restored the function and structure of the thyroid in an HT model, and Na₂SeO₃ promoted the growth, improved the secretion, and the antioxidant capacity of AMSCs in vitro. This combination treatment may provide a new therapy for patients with HT.

Comorbidities and the risk of severe or fatal outcomes associated with coronavirus disease 2019: A systematic review and meta-analysis

OBJECTIVES

Existing findings regarding the relationship between comorbidities and the severity of coronavirus disease 2019 (COVID-19) are inconsistent and insufficient. The aim of this study was to evaluate the association between different comorbidities and the severity of COVID-19.

METHODS

The PubMed, Embase, and Cochrane Library databases were searched to identify studies reporting the rates of comorbidities in COVID-19 patients with severe/fatal outcomes. Subgroup analyses were conducted according to disease severity and the country of residence. Odds ratios (OR) with 95% confidence intervals (CI) were pooled using random-effects models.

RESULTS

A total of 34 eligible studies were identified. In patients with severe/fatal COVID-19, the most prevalent chronic comorbidities were obesity (42%, 95% CI 34-49%) and hypertension (40%, 95% CI 35-45%), followed by diabetes (17%, 95% CI 15-20%), cardiovascular disease (13%, 95% CI 11-15%), respiratory disease (8%, 95% CI 6-10%), cerebrovascular disease (6%, 95% CI 4-8%), malignancy (4%, 95% CI 3-6%), kidney disease (3%, 95% CI 2-4%), and liver disease (2%, 95% CI 1-3%). In order of the prediction, the pooled ORs of the comorbidities in patients with severe or fatal COVID-19 when compared to patients with non-severe/fatal COVID-19 were as follows: chronic respiratory disease, OR 3.56 (95% CI 2.87-4.41); hypertension, OR 3.17 (95% CI 2.46-4.08); cardiovascular disease, OR 3.13 (95% CI 2.65-3.70); kidney disease, OR 3.02 (95% CI 2.23-4.08); cerebrovascular disease, OR 2.74 (95% CI 1.59-4.74); malignancy, OR 2.73 (95% CI 1.73-4.21); diabetes, OR 2.63 (95% CI 2.08-3.33); and obesity, OR 1.72 (95% CI 1.04-2.85). No correlation was observed between liver disease and COVID-19 aggravation (OR 1.54, 95% CI 0.95-2.49).

CONCLUSIONS

Chronic comorbidities, including obesity, hypertension, diabetes, cardiovascular disease, cerebrovascular disease, respiratory disease, kidney disease, and malignancy are clinical risk factors for a severe or fatal outcome associated with COVID-19, with obesity being the most prevalent and respiratory disease being the most strongly predictive. Knowledge of these risk factors could help clinicians better identify and manage the high-risk populations.

Low-dose CT of paediatric paranasal sinus using an ultra-low tube voltage (70 kVp) combined with the flash technique

AIM

To evaluate the radiation dose and diagnostic image quality of low-dose computed tomography (CT) of the paranasal sinus in children, with acquisition at an ultra-low tube voltage (70 kVp) combined with the Flash technique.

MATERIALS AND METHODS

Eighty paediatric patients underwent CT of the paranasal sinus and were divided into two groups according to different protocols (group A: 80 kVp protocol with conventional spiral mode [n=40] and group B: 70 kVp protocol with Flash scan mode [n=40]). For each examination, the CT dose index (CTDIvol), dose-length product (DLP), and effective dose (ED) were estimated. The image noise, signal-to-noise ratio (SNR), and overall subjective diagnostic image quality were also evaluated.

RESULTS

For radiation dose, the CTDIvol (mGy), DLP (mGy·cm), and ED (mSv) values of the 70 kVp protocol were significantly lower than those of the 80 kVp protocol (CTDIvol: 1.57±0.009 versus 0.39±0.004 mGy, p<0.001; DLP: 19.88±2.01 versus 6.31±0.52 mGy·cm, p<0.001; ED: 0.079±0.016 versus 0.024±0.005 mSv, p<0.001). Compared with those of the 80-kVp protocol, the image noise increased by 40.7% (p=0.113), the SNR_soft-tissue decreased by 48.9%, and the SNR_bone increased by 10.1% with the 70-kVp protocol (p=0.176 and 0.227, respectively). There was no significant difference in the overall subjective image quality grades between these two groups (p=0.15).

CONCLUSION

When imaging the paranasal sinus in children, an ultra-low tube voltage (70 kVp) combined with the Flash CT technique can reduce the radiation dose significantly while maintaining diagnostic image quality with clinically acceptable image noise.

Generation of the induced pluripotent stem cell(iPSC) line (AHQUi001-A) from a patient with familial hypertriglyceridemia (FHTG) carrying a heterozygous p.C310R (c.928 T > C) mutation in LPL gene

Familial hypertriglyceridemia (FHTG) is an autosomal dominant disorder of lipoprotein metabolism, partly caused by mutations in the LPL gene, which encodes for the lipoprotein lipase. LPL deficiency can impair triglyceride hydrolysis which causes elevated plasma triglyceride levels. An induced pluripotent stem cell (iPSC) line was generated from peripheral blood mononuclear cells (PBMCs) of a 53 years-old male patient with FHTG who had a heterozygous p.C310R (c.928 T > C) mutation in the LPL gene based on the sendai virus delivery system. The cellular model will offer a powerful tool to investigate pathogenic mechanisms in FHTG and to develop a treatment for FHTG.

Hypermethylation of the RSK4 promoter associated with BRAF V600E promotes papillary thyroid carcinoma

Ribosomal S6 kinase 4 (RSK4) is a putative tumor suppressor gene which is inactivated by epigenetic events in a number human malignancies; however, its role in papillary thyroid carcinoma (PTC) remains largely unknown. The aim of this study was to explore the methylation status of the RSK4 promoter in PTC, and to determine its potential role in thyroid carcinogenesis. Reverse transcription‑quantitative PCR (RT‑qPCR) and western blot analyses were performed to examine the RSK4 mRNA and protein levels, respectively. Methylation‑specific PCR (MSP) and bisulfite genomic sequencing (BGS) were used to analyze methylation status of the RSK4 gene. Sanger sequencing was further carried out to detect the BRAF V600E mutation. Cell proliferation assay was finally performed to evaluate the role of hypermethylation in the growth of PTC cells. The association between RSK4 methylation and the clinicopathological characteristics of patients with PTC was assessed. The methylation frequency of the RSK4 promoter in PTC tissues was higher than that in paired paracancerous tissues. Coincidentally, the RSK4 mRNA levels were also downregulated in PTC tissues when compared with the paracancerous counterparts. The hypermethylation of RSK4 was associated with tumor size and lymph node metastasis. Furthermore, the BRAF V600E mutation may influence RSK4 expression and methylation. Moreover, RSK4 hypermethylation was observed in thyroid cancer cell lines, which was consistent with a lack of RSK4 expression. Upon the 5‑Aza‑deoxycytidine treatment of thyroid cancer cells, RSK4 expression was significantly upregulated, while cell proliferation was inhibited. On the whole, the findings of the present study demonstrate that the hypermethylation of the RSK4 promoter may be one of the mechanisms responsible for the poor RSK4 expression in PTC. Thus, these data suggest that RSK4 may serve as a molecular target for the early diagnosis and treatment of PTC.

Mitochondrial DNA: A New Predictor of Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a common cause of end-stage renal disease, and diagnosis and treatment in time can help delay its progress. At present, there are more and more studies on the pathogenesis of DKD; mitochondrial dysfunction plays an important role in DKD. The occurrence and development of DKD is closely related to epigenetic changes and the interaction between mtDNA, ROS, inflammatory factors, and endothelial damage, which continuously aggravates kidney. The change of mtDNA is both the cause of DKD and the result of DKD. It is of great significance to incorporate the change of mtDNA into the monitoring of patients with diabetes. Existing evidence indicates that changes in mtDNA copy number in blood and urine reflect mitochondrial dysfunction and the severity of DKD. However, large-scale, long-term follow-up clinical trials are still needed to determine the threshold range. By the time, mitochondrial-targeted antioxidants will become a new method for the treatment of DKD and other diabetic complications; mtDNA also can be a therapeutic target for them.

Clinical outcomes of ultrasound-guided radiofrequency ablation for the treatment of primary papillary thyroid microcarcinoma

AIM

To evaluate the safety, efficacy, and long-term outcomes of ultrasound-guided radiofrequency ablation (RFA) for the treatment of primary papillary thyroid microcarcinoma (PTMC).

MATERIALS AND METHODS

A total of 37 patients with 38 PTMC nodules underwent RFA at a power of 20 W between September 2014 and December 2017. The clinical data of these patients were reviewed retrospectively and analysed. Imaging studies of the nodules were conducted, and the patients' thyroid function was assessed before RFA; 1, 3, 6, and 12 months after RFA; and every 6 months thereafter. The volumes and volume reduction rate (VRR) of the nodules were also calculated.

RESULTS

RFA with a low power of 20 W was used in the treatment of 37 patients with 38 PTMC nodules. All nodules achieved complete ablation, no complications occurred, and thyroid function was not affected. During follow-up, the volume of the nodules gradually decreased. Twelve months after ablation, the mean volumes of the nodules significantly decreased to 0.01±0.03 ml with a VRR of 99.34±3.49%. At a median follow-up of 6 (range: 1-18) months, 37 of the 38 nodules were completely absorbed, and no recurrence was observed in all 37 patients.

CONCLUSIONS

Low-power RFA showed good safety and promising efficacy outcomes for the treatment of PTMC. In addition to surgery and active surveillance, RFA may be an alternative treatment option for patients with PTMC.

The combined effect of mesenchymal stem cells and resveratrol on type 1 diabetic neuropathy

Diabetic neuropathy (DN) is one of the most common diabetic complications that results in an increase in patient discomfort and pain. The present study demonstrated that mesenchymal stem cells (MSCs) or resveratrol (RSV) may improve diabetic hyperglycemia and neuropathy. The aim of the present study was to investigate the combined effect of MSCs and RSV on DN. A total of 100 non-obese diabetic mice were divided into the following six groups: Normal control, MSCs, RSV, MSCs + RSV, insulin and diabetic control groups. Following homologous therapy, the levels of blood glucose and C-peptide, islets, nuclear factor (NF)-κB, nerve growth factor (NGF) and myelin basic protein (MBP), and the sciatic nerve structure in each group were examined and evaluated. Following the administration of therapy, the levels of blood glucose and C-peptide in mice in the MSCs + RSV group were significantly improved when compared with the other diabetic groups, and the dosage of insulin therapy required was the lowest among the six experimental groups (P<0.05). The levels of NGF, MBP and NF-κB in the MSCs + RSV group were significantly improved compared with the MSCs and RSV groups (P<0.05). Furthermore, the diameter of the axon, number of myelinated nerve fibers and the depth of the myelin sheath in the MSCs + RSV group were greatest among the five examined groups (excluding the control). The combination of RSV and MSCs could relieve hyperglycemia and improve DN. This indicated that the combination of RSV and MSCs may be a novel therapeutic method for the treatment of DN.

Elevated free fatty acid level is associated with insulin-resistant state in nondiabetic Chinese people

BACKGROUND

Free fatty acids (FFAs) are associated with insulin secretion and insulin resistance. However, the associations among FFAs, obesity, and progression from a normal to a prediabetic state are unclear.

METHODS

Nondiabetic subjects (5,952) were divided in two groups according to their body mass index (BMI): obese subjects (BMI ≥24 kg/m²) and nonobese subjects (BMI <24 kg/m²). Clinical and multiple glucolipid metabolism data were collected. The homeostasis model assessment for insulin resistance (HOMA-IR) and β-cell function (HOMA-β) was used. HbA1c level between 5.7% and 6.4% was considered prediabetic. Nonparametric tests, one-way ANOVA, and linear correlation analysis were performed. R and SPSS 23.0 software programs were used to analyze the results.

RESULTS

A U-shaped relationship between FFAs and HOMA-IR was observed. After adjusting for potential confounders, the turning points of FFA levels in the curves were 0.54 mmol/L in the nonobese group and 0.61 mmol/L in the obese group. HOMA-IR levels decreased with increasing FFA concentrations before the turning points (regression coefficient [β]= - 0.9, P=0.0111, for the nonobese group; β=0.2, P=0.5094, for the obese group) and then increased (β=0.9, P=0.0069, for the nonobese group; β=1.5, P=0.0263 for the obese group) after the points. Additionally, our study also identified that FFAs were associated with the prediabetes status in obese individuals.

CONCLUSION

FFA levels were associated with insulin resistance in nondiabetic subjects, and HOMA-IR in nonobese individuals was more sensitive to FFA changes. Monitoring and controlling plasma FFA levels in obese subjects is significant in decreasing insulin resistance and preventing diabetes.

Astragalus polysaccharides decrease proliferation, migration, and invasion but increase apoptosis of human osteosarcoma cells by up-regulation of microRNA-133a

Osteosarcoma (OS) has a high incidence, malignity, and frequency of recurrence and metastasis. In this study, we aimed to explore the potential anti-cancer effects of Astragalus polysaccharides (APS) on human OS MG63 cells as well as underlying mechanisms. Viability of MG63 cells was assessed by CCK-8 assay to determine the adequate concentration of APS. Then, effects of APS on MG63 cell proliferation, cell cycle distribution, apoptosis, and migration and invasion were analyzed by BrdU incorporation, PI staining, flow cytometry, and transwell assays, respectively. The expression levels of proteins involved in these physiological processes were assessed by western blot analysis. Afterwards, miR-133a level in APS-treated cells was determined by qRT-PCR, and whether APS affected MG63 cells through regulation of miR-133a was determined. Finally, the activation of c-Jun N-terminal protein kinase (JNK) pathway was detected. We found that APS treatment suppressed the viability, proliferation, migration, and invasion of MG63 cells, as well as induced cell apoptosis. Moreover, APS enhanced the expression of miR-133a in MG63 cells. Knockdown of miR-133a reversed the APS treatment-induced MG63 cell proliferation, migration and invasion inhibition, as well as cell apoptosis. Furthermore, APS inactivated JNK pathway in MG63 cells. Knockdown of miR-133a reversed the APS treatment-induced inactivation of JNK pathway in MG63 cells. To conclude, APS repressed proliferation, migration, and invasion while induced apoptosis of OS MG63 cells by up-regulating miR-133a and then inactivating JNK pathway.

TIPE2 acts as a biomarker for tumor aggressiveness and suppresses cell invasiveness in papillary thyroid cancer (PTC)

Background

Tumor necrosis factor (TNF)-alpha-induced protein 8-like 2 (TIPE2 or TNFAIP8L2) is a newly described negative immune regulator and is closely associated with various tumors. However, the expression and roles of TIPE2 in PTC is unknown.

Results

In the present study, TIPE2 upregulation in PTC tissues was found to be negatively associated with tumor size, capsule infiltration, peripheral infiltration and tumor T stage, which could be used to predict tumor invasiveness. TIPE2 overexpression significantly suppressed the viability, proliferation, migration and invasion of PTC cells. Moreover, TIPE2 suppressed tumor invasiveness by inhibiting Rac1, leading to decreased expression of uPA and MMP9.

Conclusions

These results indicate that TIPE2 is a potential biomarker for predicting tumor aggressiveness and suppresses tumor invasiveness in a Rac1-dependent manner.

Electronic supplementary material

The online version of this article (10.1186/s13578-018-0247-x) contains supplementary material, which is available to authorized users.

Expressions of IGF-1, ERK, GLUT4, IRS-1 in metabolic syndrome complicated with colorectal cancer and their associations with the clinical characteristics of CRC

BACKGROUND

Epidemiological data have revealed that colorectal cancer (CRC) risk is increased in patients with Metabolic syndrome.

OBJECTIVE

To explore the expressions of IGF-1, ERK, GLUT4, IRS-1 in MS patients with CRC and their associations with the clinical characteristics of CRC.

METHODS

We investigated the expressions of IGF-1, ERK, GLUT4 and IRS-1 in greater omental adipose tissues of 168 MS patients with/without CRC, 85 CRC patients without MS and 98 healthy controls by RT-PCR, and analyzed the relationships between their expressions and clinical characteristics of CRC.

RESULTS

The expression levels of IGF-1 and ERK in MS patients with/without CRC were higher while the expression levels of GLUT4 were lower compared with CRC patients without MS and healthy controls (P< 0.01). The expression levels of IGF-1 and ERK in MS patients with CRC were higher while expression levels of GLUT4 were lower compared to MS patients without CRC (P< 0.01). Expression levels of ERK, IGF-1, GLUT4 were associated with clinical characteristics of CRC, including tumor size, distant metastasis and advanced stages (III/IV) (P< 0.05).

CONCLUSIONS

Expressions of IGF-1, ERK and GLUT4 in greater omental adipose tissues might be useful biomarkers and predictive targets in the diagnosis of CRC.

Cortistatin inhibits arterial calcification in rats via GSK3β/β-catenin and protein kinase C signalling but not c-Jun N-terminal kinase signalling

AIM

Cortistatin (CST) is a newly discovered endogenous active peptide that exerts protective effects on the cardiovascular system. However, the relationship between CST and aortic calcification and the underlying mechanism remain obscure. Therefore, we investigated effects of CST on aortic calcification and its signalling pathways.

METHODS

Calcium content and alkaline phosphatase (ALP) activity were measured using the o-cresolphthalein colorimetric method and ALP assay kit respectively. Protein expression of smooth muscle (SM)-ɑ-actin, osteocalcin (OCN), β-catenin, glycogen synthase kinase 3β (GSK3β), p-GSK3β, protein kinase C (PKC), p-PKC, c-Jun N-terminal kinase (JNK) and p-JNK was determined using Western blotting.

RESULTS

In aorta from a rat vitamin D3 calcification model, CST abrogated calcium deposition and pathological damage, decreased the protein expression of OCN and β-catenin and increased SM-ɑ-actin expression. In a rat cultured vascular smooth muscular cell (VSMC) calcification model induced by β-glycerophosphate (β-GP), CST inhibited the increase in ALP activity, calcium content and OCN protein and the decrease in SM-α-actin expression. CST also inhibited the β-GP-induced increase in p-GSK3β and β-catenin protein (both P < .05). The inhibitory effects of CST on ALP activity, calcium deposition and β-catenin protein were abolished by pretreatment with lithium chloride, a GSK3β inhibitor. CST promoted the protein expression of p-PKC by 68.5% (P < .01), but not p-JNK. The ability of CST to attenuate β-GP-induced increase in ALP activity, calcium content and OCN expression in the VSMC model was abolished by pretreatment with the PKC inhibitor Go6976.

CONCLUSION

These results indicate that CST inhibits aortic calcification and osteogenic differentiation of VSMCs likely via the GSK3β/β-catenin and PKC signalling pathways, but not JNK signalling pathway.

N-Acetyl-Glucosamine Sensitizes Non-Small Cell Lung Cancer Cells to TRAIL-Induced Apoptosis by Activating Death Receptor 5

BACKGROUND/AIMS

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a potential anti-cancer agent due to its selective toxicity. However, many human non-small cell lung cancer (NSCLC) cells are partially resistant to TRAIL, thereby limiting its clinical application. Therefore, there is a need for the development of novel adjuvant therapeutic agents to be used in combination with TRAIL.

METHODS

In this study, the effect of N-acetyl-glucosamine (GlcNAc), a type of monosaccharide derived from chitosan, combined with TRAIL was evaluated in vitro and in vivo. Thirty NSCLC clinical samples were used to detect the expression of death receptor (DR) 4 and 5. After GlcNAc and TRAIL co-treatment, DR expression was determined by real-time PCR and western blotting. Cycloheximide was used to detect the protein half-life to further understand the correlation between GlcNAc and the metabolic rate of DR. Non-reducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis was used to detect receptor clustering, and the localization of DR was visualized by immunofluorescence under a confocal microscope. Furthermore, a co-immunoprecipitation assay was performed to analyze the formation of death-inducing signaling complex (DISC). O-linked glycan expression levels were evaluated following DR5 overexpression and RNA interference mediated knockdown.

RESULTS

We found that the clinical samples expressed higher levels of DR5 than DR4, and GlcNAc co-treatment improved the effect of TRAIL-induced apoptosis by activating DR5 accumulation and clustering, which in turn recruited the apoptosis-initiating protease caspase-8 to form DISC, and initiated apoptosis. Furthermore, GlcNAc promoted DR5 clustering by improving its O-glycosylation.

CONCLUSION

These results uncovered the molecular mechanism by which GlcNAc sensitizes cancer cells to TRAIL-induced apoptosis, thereby highlighting a novel effective agent for TRAIL-mediated NSCLC-targeted therapy.

Severe hypertriglyceridemia due to two novel loss-of-function lipoprotein lipase gene mutations (C310R/E396V) in a Chinese family associated with recurrent acute pancreatitis

Lipoprotein lipase (LPL) is widely expressed in skeletal muscles, cardiac muscles as well as adipose tissue and involved in the catabolism of triglyceride. Herein we have systematically characterized two novel loss-of-function mutations in LPL from a Chinese family in which afflicted members were manifested by severe hypertriglyceridemia and recurrent pancreatitis. DNA sequencing revealed that the proband was a heterozygote carrying a novel c.T928C (p.C310R) mutation in exon 6 of the LPL gene. Another member of the family was detected to be a compound heterozygote who along with the c.T928C mutation also carried a novel missense mutation c.A1187T (p.E396V) in exon 8 of the LPL gene. Furthermore, COS-1 cells were transfected with lentiviruses containing the mutant LPL genes. While C310R markedly reduced the overall LPL protein level, COS-1 cells carrying E396V or double mutations contained similar overall LPL protein levels to the wild-type. The specific activity of the LPL mutants remained at comparable magnitude to the wild-type. However, few LPL were detected in the culture medium for the mutants, suggesting that both mutations caused aberrant triglyceride catabolism. More specifically, E396V and double mutations dampened the transport of LPL to the cell surface, while for the C310R mutation, reducing LPL protein level might be involved. By characterizing these two novel LPL mutations, this study has expanded our understanding on the pathogenesis of familial hypertriglyceridemia (FHTG).

Fasting plasma glucose and serum uric acid levels in a general Chinese population with normal glucose tolerance: A U-shaped curve

Objective

Although several epidemiological studies assessed the relationship between fasting plasma glucose (FPG) and serum uric acid (SUA) levels, the results were inconsistent. A cross-sectional study was conducted to investigate this relationship in Chinese individuals with normal glucose tolerance.

Research design and methods

A total of 5,726 women and 5,457 men with normal glucose tolerance were enrolled in the study. All subjects underwent a 75-g oral glucose tolerance test. Generalized additive models and two-piecewise linear regression models were applied to assess the relationship.

Results

A U-shaped relationship between FPG and SUA was observed. After adjusting for potential confounders, the inflection points of FPG levels in the curves were 4.6 mmol/L in women and 4.7 mmol/L in men respectively. SUA levels decreased with increasing fasting plasma glucose concentrations before the inflection points (regression coefficient [β] = -36.4, P < 0.001 for women; β = -33.5, P < 0.001 for men), then SUA levels increased (β = 17.8, P < 0.001 for women; β = 13.9, P < 0.001 for men). Additionally, serum insulin levels were positively associated with FPG and SUA (P < 0.05).

Conclusions

A U-shaped relationship between FPG and SUA levels existed in Chinese individuals with normal glucose tolerance. The association is partly mediated through serum insulin levels.

Intramuscular injection of human umbilical cord-derived mesenchymal stem cells improves cardiac function in dilated cardiomyopathy rats

Background

Stem cells provide a promising candidate for the treatment of the fatal pediatric dilated cardiomyopathy (DCM). This study aimed to investigate the effects of intramuscular injection of human umbilical cord-derived mesenchymal stem cells (hUCMSCs) on the cardiac function of a DCM rat model.

Methods

A DCM model was established by intraperitoneal injections of doxorubicin in Sprague-Dawley rats. hUCMSCs at different concentrations or cultured medium were injected via limb skeletal muscles, with blank medium injected as the control. The rats were monitored for 4 weeks, meanwhile BNP, cTNI, VEGF, HGF, GM-CSF, and LIF in the peripheral blood were examined by ELISA, and cardiac function was monitored by echocardiography (Echo-CG). Finally, the expression of IGF-1, HGF, and VEGF in the myocardium was examined by histoimmunochemistry and real-time PCR, and the ultrastructure of the myocardium was examined by electron microscopy.

Results

Injection of hUCMSCs markedly improved cardiac function in the DCM rats by significantly elevating left ventricular ejection fraction (LVEF) and left ventricular fraction shortening (LVFS). The BNP and cTNI levels in the peripheral blood were reduced by hUCMSCs, while HGF, LIF, GM-CSF, and VEGF were increased by hUCMSCs. Expression of IGF-1, HGF, and VEGF in the myocardium from the DCM rats was significantly increased by hUCMSC injection. Furthermore, hUCMSCs protected the ultrastructure of cardiomyocytes by attenuating mitochondrial swelling and maintaining sarcolemma integrity.

Conclusions

Intramuscular injection of UCMSCs can improve DCM-induced cardiac function impairment and protect the myocardium. These effects may be mediated by regulation of relevant cytokines in serum and the myocardium.

Electronic supplementary material

The online version of this article (doi:10.1186/s13287-017-0472-y) contains supplementary material, which is available to authorized users.

Overexpression of JARID1B promotes differentiation via SHIP1/AKT signaling in human hypopharyngeal squamous cell carcinoma

Histone H3 (H3K4) demethylase JARID1B is aberrantly upregulated in many types of tumor and has been proposed to function as oncogene. Here we show that JARID1B is elevated in moderate and high-differentiated human hypopharyngeal squamous cell carcinoma (HPSCC) compared with low-differentiated HPSCC. Overexpression of JARID1B in FaDu cells increased epithelial differentiation marker K10 expression and inhibited cell proliferation. JARID1B and K10 mRNA expression is high correlated in HPSCC patients. Mechanistically, we found JARID1B directly bound to PI3K/AKT signaling inhibitor SHIP1 gene promoter and decreased SHIP1 gene expression. Activation of downstream AKT resulted in increased β-catenin signaling, by which promoted target genes Fra-1 and Jun, together with other AP-1 transcription factors, leading to K10 expression. Forced expression of SHIP1 rescued JARID1B-induced phenotypes on FaDu cell differentiation and proliferation. Taken together, our findings provide first evidence that elevated expression of JARID1B has a critical role in promoting HPSCC differentiation and inhibiting proliferation, suggesting JARID1B may function as a tumor suppressor in squamous cell cancers and implying a novel important therapeutic strategy of HPSCC.

Eye on the B-ALL: B-cell receptor repertoires reveal persistence of numerous B-lymphoblastic leukemia subclones from diagnosis to relapse

The strongest predictor of relapse in B-cell acute lymphoblastic leukemia (B-ALL) is the level of persistence of tumor cells after initial therapy. The high mutation rate of the B-cell receptor (BCR) locus allows high-resolution tracking of the architecture, evolution and clonal dynamics of B-ALL. Using longitudinal BCR repertoire sequencing, we find that the BCR undergoes an unexpectedly high level of clonal diversification in B-ALL cells through both somatic hypermutation and secondary rearrangements, which can be used for tracking the subclonal composition of the disease and detect minimal residual disease with unprecedented sensitivity. We go on to investigate clonal dynamics of B-ALL using BCR phylogenetic analyses of paired diagnosis-relapse samples and find that large numbers of small leukemic subclones present at diagnosis re-emerge at relapse alongside a dominant clone. Our findings suggest that in all informative relapsed patients, the survival of large numbers of clonogenic cells beyond initial chemotherapy is a surrogate for inherent partial chemoresistance or inadequate therapy, providing an increased opportunity for subsequent emergence of fully resistant clones. These results frame early cytoreduction as an important determinant of long-term outcome.

Pathogenic connexin-31 forms constitutively active hemichannels to promote necrotic cell death

Mutations in Connexin-31 (Cx31) are associated with multiple human diseases including erythrokeratodermia variabilis (EKV). The molecular action of Cx31 pathogenic mutants remains largely elusive. We report here that expression of EKV pathogenic mutant Cx31R42P induces cell death with necrotic characteristics. Inhibition of hemichannel activity by a connexin hemichannel inhibitor or high extracellular calcium suppresses Cx31R42P-induced cell death. Expression of Cx31R42P induces ER stress resulting in reactive oxygen species (ROS) production, in turn, to regulate gating of Cx31R42P hemichannels and Cx31R42P induced cell death. Moreover, Cx31R42P hemichannels play an important role in mediating ATP release from the cell. In contrast, no hemichannel activity was detected with cells expressing wildtype Cx31. Together, the results suggest that Cx31R42P forms constitutively active hemichannels to promote necrotic cell death. The Cx31R42P active hemichannels are likely resulted by an ER stress mediated ROS overproduction. The study identifies a mechanism of EKV pathogenesis induced by a Cx31 mutant and provides a new avenue for potential treatment strategy of the disease.