The impact of calcineurin inhibitors on insulin sensitivity and insulin secretion: a randomized crossover trial in uraemic patients

Leptin receptor gene polymorphisms in kidney transplant patients with post-transplant diabetes mellitus treated with tacrolimus

Post-transplant diabetes mellitus (PTDM) is a metabolic complication that often occurs after kidney transplantation. Factors that increase the risk of this complication are currently being researched, including polymorphisms in genes affecting carbohydrate-lipid metabolism. Leptin is a hormone that affects appetite and adipose tissue and plays an important role in regulating insulin secretion as well as glucose and lipid metabolism. The aim of this study was to examine the association between leptin receptor gene polymorphisms and the development of post-transplant diabetes mellitus in patients treated with tacrolimus. The study was carried out in a group of 201 patients who underwent kidney transplantation. The follow-up period was 12 months. PTDM was diagnosed in 35 patients. Analysing the LEPR gene rs1137101 polymorphism, we observed in patients with PTDM an increased frequency of GG genotype carriers (GG vs AA, OR 3.36; 95 % CI 0.99-11.46; p = 0.04). There were no statistically significant differences in the distribution of the LEPR rs1137100 and LEPR rs1805094 polymorphisms between patients with and without PTDM. Multivariate regression analysis confirmed that female sex, advanced age, increased BMI and a higher number of LEPR rs1137101 G alleles were independent risk factors for PTDM development. The risk of PTDM development was almost 3.5 times greater in LEPR rs1137101 G allele carriers than in AA homozygotes (GG + AG vs AA; OR 3.48; 95 %CI (1.09-11.18), p = 0.035). The results suggest that patients after kidney transplantation with the LEPR gene rs1137101 G allele may have an increased risk of post-transplant diabetes development.

Body Mass Index and Cause-Specific Mortality after Lung Transplantation in the United States

Rationale: Low and high body mass index (BMI) are associated with increased mortality after lung transplantation. Why extremes of BMI might increase risk of death is unknown. Objectives: To estimate the association of extremes of BMI with causes of death after transplantation. Methods: We performed a retrospective study of the United Network for Organ Sharing database, including 26,721 adults who underwent lung transplantation in the United States between May 4, 2005, and December 2, 2020. We mapped 76 reported causes of death into 16 distinct groups. We estimated cause-specific hazards for death from each cause using Cox models. Results: Relative to a subject with a BMI of 24 kg/m2, a subject with a BMI of 16 kg/m2 had 38% (hazard ratio [HR], 1.38; 95% confidence interval [95% CI], 0.99-1.90), 82% (HR, 1.82; 95% CI, 1.34-2.46), and 62% (HR, 1.62; 95% CI, 1.18-2.22) increased hazards of death from acute respiratory failure, chronic lung allograft dysfunction (CLAD), and infection, respectively, and a subject with a BMI of 36 kg/m2 had 44% (HR, 1.44; 95% CI, 0.97-2.12), 42% (HR, 1.42; 95% CI, 0.93-2.15), and 185% (HR, 2.85; 95% CI, 1.28-6.33) increased hazards of death from acute respiratory failure, CLAD, and primary graft dysfunction, respectively. Conclusions: Low BMI is associated with increased risk of death from infection, acute respiratory failure, and CLAD after lung transplantation, whereas high BMI is associated with increased risk of death from primary graft dysfunction, acute respiratory failure, and CLAD.

Topical Glucocorticoid Use and the Risk of Posttransplant Diabetes

Systemically administered glucocorticoids constitute an essential part of the immunosuppressive regimen for transplant recipients, yet their known risks of causing hyperglycemia or posttransplant diabetes require close monitoring and minimisation of use, when possible, to prevent detrimental effects on patient morbidity and graft survival. Topical glucocorticoids, on the other hand, are rarely considered to affect glucose metabolism and therefore seldomly monitored, despite their wide and in some cases, long-term use. We report a case of a renal transplant recipient presenting with acute hyperosmolar hyperglycemia after treatment with topical glucocorticoids and present a mini review of the literature.

Glucagon-like peptide-1 receptor agonists and sodium-glucose cotransporter 2 inhibitors for diabetes after solid organ transplantation

Post-transplant diabetes mellitus (PTDM) is a common complication of solid organ transplantation and a major cause of increased morbidity and mortality. Additionally, solid organ transplant patients may have pre-existent type 2 diabetes mellitus (T2DM). While insulin is the treatment of choice for hyperglycemia in the first weeks after transplantation, there is no preferred first line agent for long-term management of PTDM or pre-existent T2DM. Glucagon-like peptide-1 receptor agonists (GLP-1RA) and sodium-glucose cotransporter 2 (SGLT2) inhibitors improve glycemic control, lower body weight, and blood pressure, are recommended after lifestyle and metformin as initial therapy for diabetic patients with cardiovascular or kidney comorbidities regarding their cardiorenal benefits. Furthermore, the mechanisms of action of GLP-1RA may counteract some of the driving forces for PTDM, as calcineurin-induced β cell toxicity as per preclinical data, and improve obesity. However, their use in the treatment of PTDM is currently limited by a paucity of data. Retrospective observational and small exploratory studies suggest that GLP-1RA effectively improve glycemic control and induce weight loss in patients with PTDM without interacting with commonly used immunosuppressive agents, although randomized-controlled clinical trials are required to confirm their safety and efficacy. In this narrative review, we evaluate the risk factors and pathogenesis of PTDM and compare the potential roles of GLP-1RA and SGLT2 inhibitors in PTDM prevention and management as well as in pre-existent T2DM, and providing a roadmap for evidence generation on newer antidiabetic drugs for solid organ transplantation.

Post-Transplant Diabetes Mellitus and Prediabetes in Renal Transplant Recipients: An Update

Post-transplant diabetes mellitus (PTDM) is a frequent and relevant complication after renal transplantation: it affects 20-30% of renal transplant recipients and increases the risk for cardiovascular and infectious events. Thus, understanding pathogenesis of PTDM would help limiting its consequences. In this review, we analyse novel aspects of PTDM, based on studies of the last decade, such as the clinical evolution of PTDM, early and late, the reversibility rate, diagnostic criteria, risk factors, including pre-transplant metabolic syndrome and insulin resistance (IR) and the interaction between these factors and immunosuppressive medications. Also, we discuss novel pathogenic factors, in particular the role of β-cell function in an environment of IR and common pathways between pre-existing cell damage and tacrolimus-induced toxicity. The relevant role of prediabetes in the pathogenesis of PTDM and cardiovascular disease is also addressed. Finally, current evidence on PTDM treatment is discussed.

Clinical considerations in the management of non-alcoholic steatohepatitis cirrhosis pre- and post-transplant: A multi-system challenge

Non-alcoholic steatohepatitis (NASH) is the most common chronic liver disease worldwide, and the fastest growing indication for liver transplantation in the United States. NASH is now the leading etiology for liver transplantation in women, the second leading indication for men, and the most common cause amongst recipients aged 65 years and older. Patients with end-stage liver disease related to NASH represent a unique and challenging patient population due the high incidence of associated comorbid diseases, including obesity, type 2 diabetes (T2D), and hypertension. These challenges manifest in the pre-liver transplantation period with increased waitlist times and waitlist mortality. Furthermore, these patients carry considerable risk of morbidity and mortality both before after liver transplantation, with high rates of T2D, cardiovascular disease, chronic kidney disease, poor nutrition, and disease recurrence. Successful transplantation for these patients requires identification and management of their comorbidities in the face of liver failure. Multidisciplinary evaluations include a thorough pre-transplant workup with a complete cardiac evaluation, control of diabetes, nutritional support, and even, potentially, consultation with a bariatric surgeon. This article provides a comprehensive review of the conditions and challenges facing patients with NASH cirrhosis undergoing liver transplantation and provides recommendations for evaluation and management to optimize them before liver transplantation to produce successful outcomes.

FXR activation alleviates tacrolimus-induced post-transplant diabetes mellitus by regulating renal gluconeogenesis and glucose uptake

BACKGROUND

Tacrolimus (FK506)-induced diabetes mellitus is one of the most important factors of post-transplant diabetes mellitus (PTDM). However, the detailed mechanisms underlying PTDM are still unclear. Farnesoid X receptor (FXR) regulates glycolipid metabolism. The objective of this study was to explore whether FXR is involved in the development of tacrolimus-induced diabetes mellitus.

METHODS

After C57BL/6J mice were treated with tacrolimus (FK506) for 3 months, the fasting blood glucose levels, body weights, renal morphological alterations, and mRNA expression levels of phosphoenolpyruvate carboxykinase (PEPCK) and glucose transporter 2 (GLUT2) among the control group, the FK506 group and the FK506 + GW4064 (a FXR agonist) group (n = 7) were measured. The intracellular location of peroxisome proliferator activated receptor γ coactivator-1α (PGC1α) and forkhead box O1 (FOXO1) was detected by immunofluorescence. Human renal cortex proximal tubule epithelial cells (HK-2) were treated with 15 μM FK506 or 4 μM FXR agonist (GW4064) for 24, 48 and 72 h, and the expression levels of FXR, gluconeogenesis and glucose uptake, representing the enzymes PEPCK and GLUT2, were detected with real-time PCR and western blot analyses. Finally, the mRNA levels of PEPCK and GLUT2 in HK-2 cells were measured after FXR was upregulated.

RESULTS

FK506 significantly inhibited the mRNA and protein levels of FXR at 48 h and 72 h in HK-2 cells (P < 0.05). Meanwhile, FK506 promoted gluconeogenesis and inhibited glucose uptake in HK-2 cells (P < 0.05). However, overexpression of FXR in transfected HK-2 cell lines significantly inhibited gluconeogenesis and promoted glucose uptake (P < 0.05). The FXR agonist GW4064 significantly decreased the fasting blood glucose in mice challenged with FK506 for 3 months (P < 0.05), inhibited gluconeogenesis (P < 0.05) and significantly promoted glucose uptake (P < 0.05). Immunofluorescence staining and western blot analyses further revealed that FXR activation may affect the translocation of PGC1α and FOXO1 from the nucleus to the cytoplasm.

CONCLUSIONS

FXR activation may mitigate tacrolimus-induced diabetes mellitus by regulating gluconeogenesis as well as glucose uptake of renal cortex proximal tubule epithelial cells in a PGC1α/FOXO1-dependent manner, which may be a potential therapeutic strategy for the prevention and treatment of PTDM.

Conversion from Tacrolimus to Cyclosporine A Improves Glucose Tolerance in HCV-Positive Renal Transplant Recipients

Background

Calcineurin-inhibitors and hepatitis C virus (HCV) infection increase the risk of post-transplant diabetes mellitus. Chronic HCV infection promotes insulin resistance rather than beta-cell dysfunction. The objective was to elucidate whether a conversion from tacrolimus to cyclosporine A affects fasting and/or dynamic insulin sensitivity, insulin secretion or all in HCV-positive renal transplant recipients.

Methods

In this prospective, single-center study 10 HCV-positive renal transplant recipients underwent 2h-75g-oral glucose tolerance tests before and three months after the conversion of immunosuppression from tacrolimus to cyclosporine A. Established oral glucose tolerance test-based parameters of fasting and dynamic insulin sensitivity and insulin secretion were calculated. Data are expressed as median (IQR).

Results

After conversion, both fasting and challenged glucose levels decreased significantly. This was mainly attributable to a significant amelioration of post-prandial dynamic glucose sensitivity as measured by the oral glucose sensitivity-index OGIS [422.17 (370.82–441.92) vs. 468.80 (414.27–488.57) mL/min/m2, p = 0.005), which also resulted in significant improvements of the disposition index (p = 0.017) and adaptation index (p = 0.017) as markers of overall glucose tolerance and beta-cell function. Fasting insulin sensitivity (p = 0.721), insulinogenic index as marker of first-phase insulin secretion [0.064 (0.032–0.106) vs. 0.083 (0.054–0.144) nmol/mmol, p = 0.093) and hepatic insulin extraction (p = 0.646) remained unaltered. No changes of plasma HCV-RNA levels (p = 0.285) or liver stiffness (hepatic fibrosis and necroinflammation, p = 0.463) were observed after the conversion of immunosuppression.

Conclusions

HCV-positive renal transplant recipients show significantly improved glucose-stimulated insulin sensitivity and overall glucose tolerance after conversion from tacrolimus to cyclosporine A. Considering the HCV-induced insulin resistance, HCV-positive renal transplant recipients may benefit from a cyclosporine A-based immunosuppressive regimen.

Trial Registration

ClinicalTrials.gov NCT02108301

Treatment of feline asthma with ciclosporin in a cat with diabetes mellitus and congestive heart failure

A 5-year-old domestic shorthair cat that had been previously diagnosed with diabetes mellitus was presented for episodes of coughing and respiratory distress. Diagnostic testing revealed congestive heart failure secondary to hypertrophic cardiomyopathy and concurrent asthma. All clinical signs and eosinophilic airway inflammation resolved with oral ciclosporin while the cat was concurrently receiving medications for treatment of heart failure (furosemide and enalapril). Ciclosporin should be considered for treatment of feline asthma in patients with concurrent diseases (eg, diabetes mellitus, severe heart disease) that may contraindicate use of oral glucocorticoid therapy.

Adiponectin and leptin gene polymorphisms in patients with post-transplant diabetes mellitus

Background: Post-transplant diabetes mellitus (PTDM) is a common metabolic complication after organ transplantation and may be associated with the use of calcineurin inhibitors (tacrolimus and cyclosporine). Leptin and adiponectin are adipokines and play an important role in the regulation of insulin secretion as well as glucose and lipid metabolism. Aim: The aim of this study was to examine the association between adiponectin and leptin gene polymorphisms and development of PTDM. Materials & methods: The study included 323 patients who received kidney transplants and were treated with calcineurin inhibitors (tacrolimus or cyclosporine). Results: The association between adiponectin and leptin gene polymorphisms and PTDM was studied in three models of Cox regression analysis – additive, dominant and recessive. In these three models, the LEP rs2167270 gene polymorphism was statistically significantly associated with increased risk of PTDM. The association between the LEP rs2167270 polymorphism and PTDM was confirmed by multivariate regression analysis. Conclusion: The results of our study suggest an association between the leptin rs2167270 gene A allele and PTDM.

Original submitted 27 February 2015; Revision submitted 22 May 2015

Tacrolimus and sirolimus have distinct effects on insulin signaling in male and female rats

Although the contribution of the immunosuppressants tacrolimus (TAC) and sirolimus (SIR) to the development of posttransplant diabetes mellitus (PTDM) are being increasingly recognized, the mechanisms of immunosuppressant-induced hyperglycemia are unclear. SIR induces insulin resistance predominantly, but is associated with β-cell dysfunction in rodents. TAC affects islet function but is associated with worsening insulin sensitivity in a few, and improvement in some, clinical studies. We sought to clarify the contributions of TAC and SIR to insulin resistance and islet function. Four groups of male and female Sprague-Dawley rats received TAC, SIR, TAC and SIR, or control for 2 weeks. All rats were administered an oral glucose challenge at the end of treatment. Half the groups were sacrificed 10 minutes after administration of regular insulin whereas the other half did not receive insulin before sacrifice. Liver, pancreas, fat, and muscle were harvested subsequently. Quantification of Western blots revealed that SIR and TAC plus SIR suppressed the phospho-Akt (pAkt)-to-Akt ratios in liver, muscle, and fat compared with control, regardless of sex. TAC alone did not impair the pAkt-to-Akt ratios in any of the tissues in male and female rats. β-Cell mass was reduced significantly after TAC treatment in male rats. SIR did not affect β-cell mass, regardless of sex. Our study demonstrated very clearly that SIR impairs insulin signaling, without any effect on β-cell mass, and TAC does not impair insulin signaling but reduces β-cell mass. Our efforts are key to understanding the mechanisms of immunosuppressant-induced hyperglycemia and to tailoring treatments for PTDM.

Treating diabetes with islet transplantation: lessons from the past decade in Lille

Type 1 diabetes (T1D) is due to the loss of both beta-cell insulin secretion and glucose sensing, leading to glucose variability and a lack of predictability, a daily issue for patients. Guidelines for the treatment of T1D have become stricter as results from the Diabetes Control and Complications Trial (DCCT) demonstrated the close relationship between microangiopathy and HbA1c levels. In this regard, glucometers, ambulatory continuous glucose monitoring, and subcutaneous and intraperitoneal pumps have been major developments in the management of glucose imbalance. Besides this technological approach, islet transplantation (IT) has emerged as an acceptable safe procedure with results that continue to improve. Research in the last decade of the 20th century focused on the feasibility of islet isolation and transplantation and, since 2000, the success and reproducibility of the Edmonton protocol have been proven, and the mid-term (5-year) benefit-risk ratio evaluated. Currently, a 5-year 50% rate of insulin independence can be expected, with stabilization of microangiopathy and macroangiopathy, but the possible side-effects of immunosuppressants, limited availability of islets and still limited duration of insulin independence restrict the procedure to cases of brittle diabetes in patients who are not overweight or have no associated insulin resistance. However, various prognostic factors have been identified that may extend islet graft survival and reduce the number of islet injections required; these include graft quality, autoimmunity, immunosuppressant regimen and non-specific inflammatory reactions. Finally, alternative injection sites and unlimited sources of islets are likely to make IT a routine procedure in the future.

Cyclosporin A attenuates weight gain and improves glucose tolerance in diet-induced obese mice

Inflammation is a main factor responsible for obesity induced insulin resistance and type 2 diabetes. Since immunosuppressant activity is closely related with low level of inflammation, we predict that Cyclosporin A (CsA), an immunosuppressant drug, might have a protective role for combating inflammation-associated disorders such as obesity and type 2 diabetes. To address this issue, obese or lean mice were received CsA via gavage at the dose of 10mg/kg/day for 3 weeks. Our results show that CsA treatment remarkably attenuates food intake and body weight gain in the obese mice. CsA treatment down-regulates expression of gluconeogenic gene including Pepck, G6Pase and Pgc1α, leading to a decrease in blood glucose level and an improvement of glucose tolerance in the obese animals. RT-PCR analysis of genes involved in adipocyte differentiation and lipid metabolism in white adipose tissue reveal that CsA application reduces expression of Pparγ, Fas and Scd 1. The productions of pro-inflammatory cytokines (IL-1β, IL-2, IL-12 and TNFα) and JNK activity were remarkably reduced in the CsA-treated obese animals. These results suggest that CsA treatment might play beneficial effects against obesity and obesity related hyperglycemia.