Cyclosporin and tacrolimus impair insulin secretion and transcriptional regulation in INS-1E beta-cells

Management of diabetes in people with advanced chronic kidney disease

Diabetes is the commonest cause of end stage kidney disease globally, accounting for almost 40% of new cases requiring renal replacement therapy. Management of diabetes in people with advanced kidney disease on renal replacement therapy is challenging due to some unique aspects of assessment and treatment in this group of patients. Standard glycaemic assessment using glycated haemoglobin may not be valid in such patients due to altered red blood cell turnover or iron/erythropoietin deficiency, leading to changed red blood cell longevity. Therefore, use of continuous glucose monitoring may be beneficial to enable more focussed glycaemic assessment and improved adjustment of therapy. People with advanced kidney disease may be at higher risk of hypoglycaemia due to a number of physiological mechanisms, and in addition, therapeutic options are limited in such patients due to lack of experience or license. Insulin therapy is the basis of treatment of people with diabetes with advanced kidney disease due to many other drugs classes being contraindicated. Targets for glycaemic control should be adjusted according to co-morbidity and frailty, and continuous glucose monitoring should be used in people on dialysis to ensure low risk of hypoglycaemia. Post-transplant diabetes is common amongst people undergoing solid organ transplantation and confers a greater risk of mortality and morbidity in kidney transplant recipients. It should be actively screened for and managed in the post-transplant setting.

An update review of post-transplant diabetes mellitus: Concept, risk factors, clinical implications and management

OBJECTIVE

Kidney transplantation is the gold standard therapeutic alternative for patients with end-stage renal disease; nevertheless, it is not without potential complications leading to considerable morbidity and mortality such as post-transplant diabetes mellitus (PTDM). This narrative review aims to comprehensively evaluate PTDM in terms of its diagnostic approach, underlying pathophysiological pathways, epidemiological data, and management strategies.

METHODS

Articles were retrieved from electronic databases using predefined search terms. Inclusion criteria encompassed studies investigating PTDM diagnosis, pathophysiology, epidemiology, and management strategies.

RESULTS

PTDM emerges as a significant complication following kidney transplantation, influenced by various pathophysiological factors including peripheral insulin resistance, immunosuppressive medications, infections, and proinflammatory pathways. Despite discrepancies in prevalence estimates, PTDM poses substantial challenges to transplant. Diagnostic approaches, including traditional criteria such as fasting plasma glucose (FPG) and HbA1c, are limited in their ability to capture early PTDM manifestations. Oral glucose tolerance test (OGTT) emerges as a valuable tool, particularly in the early post-transplant period. Management strategies for PTDM remain unclear, within sufficient evidence from large-scale randomized clinical trials to guide optimal interventions. Nevertheless, glucose-lowering agents and life style modifications constitute primary modalities for managing hyperglycemia in transplant recipients.

DISCUSSION

The complex interplay between PTDM and the transplant process necessitates individualized diagnostic and management approaches. While early recognition and intervention are paramount, modifications to maintenance immunosuppressive regimens based solely on PTDM risk are not warranted, given the potential adverse consequences such as increased rejection risk. Further research is essential to refine management strategies and enhance outcomes for transplant recipients.

Human Menstrual Blood-Derived Stem Cells Protect against Tacrolimus-Induced Islet Dysfunction via Cystathionine β-Synthase Mediated IL-6/STAT3 Inactivation

Diabetes imposes a huge burden worldwide. Islet transplantation is an alternative therapy for diabetes. However, tacrolimus, a kind of immunosuppressant after organ transplantation, is closely related to post-transplant diabetes mellitus. Mesenchymal stem cells (MSCs) have attracted interest for their potential to alleviate diabetes. In vivo experiments revealed that human menstrual blood-derived stem cells (MenSCs) treatment improved tacrolimus-induced blood glucose, body weight, and glucose tolerance disorders in mice. RNA sequencing was used to analyze the potential therapeutic targets of MenSCs. In this study, we illustrated that cystathionine β-synthase (CBS) contributed to tacrolimus -induced islet dysfunction. Using β-cell lines (MIN6, β-TC-6), we demonstrated that MenSCs ameliorated tacrolimus-induced islet dysfunction in vitro. Moreover, MenSC reduced the tacrolimus-induced elevation of CBS levels and significantly enhanced the viability, anti-apoptotic ability, glucose-stimulated insulin secretion (GSIS), and glycolytic flux of β-cells. We further revealed that MenSCs exerted their therapeutic effects by inhibiting CBS expression to activate the IL6/JAK2/STAT3 pathway. In conclusion, we showed that MenSCs may be a potential strategy to improve tacrolimus-induced islet dysfunction.

Safety and efficacy of glucagon-like peptide-1 receptor agonists among kidney transplant recipients: a systematic review and meta-analysis

Background

Evidence supporting glucagon-like peptide-1 receptor agonists (GLP-1RAs) in kidney transplant recipients (KTRs) remains scarce. This systematic review and meta-analysis aims to evaluate the safety and efficacy of GLP-1RAs in this population.

Methods

A comprehensive literature search was conducted in the MEDLINE, Embase and Cochrane databases from inception through May 2023. Clinical trials and observational studies that reported on the safety or efficacy outcomes of GLP-1RAs in adult KTRs were included. Kidney graft function, glycaemic and metabolic parameters, weight, cardiovascular outcomes and adverse events were evaluated. Outcome measures used for analysis included pooled odds ratios (ORs) with 95% confidence intervals (CIs) for dichotomous outcomes and standardized mean difference (SMD) or mean difference (MD) with 95% CI for continuous outcomes. The protocol was registered in the International Prospective Register of Systematic Reviews (CRD 42023426190).

Results

Nine cohort studies with a total of 338 KTRs were included. The median follow-up was 12 months (interquartile range 6-23). While treatment with GLP-1RAs did not yield a significant change in estimated glomerular filtration rate [SMD -0.07 ml/min/1.73 m2 (95% CI -0.64-0.50)] or creatinine [SMD -0.08 mg/dl (95% CI -0.44-0.28)], they were associated with a significant decrease in urine protein:creatinine ratio [SMD -0.47 (95% CI -0.77 to -0.18)] and haemoglobin A1c levels [MD -0.85% (95% CI -1.41 to -0.28)]. Total daily insulin dose, weight and body mass index also decreased significantly. Tacrolimus levels remained stable [MD -0.43 ng/ml (95% CI -0.99 to 0.13)]. Side effects were primarily nausea and vomiting (17.6%), diarrhoea (7.6%) and injection site pain (5.4%).

Conclusions

GLP-1RAs are effective in reducing proteinuria, improving glycaemic control and supporting weight loss in KTRs, without altering tacrolimus levels. Gastrointestinal symptoms are the main side effects.

Defining an approach for therapeutic strategies in metabolic dysfunction-associated steatotic liver disease after liver transplantation

Occurrence of metabolic dysfunction-associated steatotic liver disease (MASLD) is common following liver transplantation (LT). MASLD can be classified as a recurrent disease when it occurs in patients receiving LT for metabolic dysfunction-associated steatohepatitis (MASH) or as de novo when it occurs in patients undergoing transplantation for non-metabolic dysfunction-associated steatohepatitis etiologies of liver disease. Fibrosis progression in patients with MASLD is accelerated, with progression to cirrhosis occurring more rapidly compared with the general (ie, non-LT) population. Moreover, the metabolic burden in LT recipients with MASLD is high and synergizes with liver disease to negatively affect the clinical course. Despite the oversized clinical burden of MASLD among LT recipients, there is currently a lack of regulatory approach and pathway for therapeutics development in this patient population. The present document, thus, provides guidance for therapeutics development that incorporates nuances of transplant care in patients with post-LT MASLD to facilitate drug development.

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.

Multifaceted relationship between diabetes and kidney diseases: Beyond diabetes

Diabetes mellitus is one of the most common causes of chronic kidney disease. Kidney involvement in patients with diabetes has a wide spectrum of clinical presentations ranging from asymptomatic to overt proteinuria and kidney failure. The development of kidney disease in diabetes is associated with structural changes in multiple kidney compartments, such as the vascular system and glomeruli. Glomerular alterations include thickening of the glomerular basement membrane, loss of podocytes, and segmental mesangiolysis, which may lead to microaneurysms and the development of pathognomonic Kimmelstiel-Wilson nodules. Beyond lesions directly related to diabetes, awareness of the possible coexistence of nondiabetic kidney disease in patients with diabetes is increasing. These nondiabetic lesions include focal segmental glomerulosclerosis, IgA nephropathy, and other primary or secondary renal disorders. Differential diagnosis of these conditions is crucial in guiding clinical management and therapeutic approaches. However, the relationship between diabetes and the kidney is bidirectional; thus, new-onset diabetes may also occur as a complication of the treatment in patients with renal diseases. Here, we review the complex and multifaceted correlation between diabetes and kidney diseases and discuss clinical presentation and course, differential diagnosis, and therapeutic oppor-tunities offered by novel drugs.

Insulin secretion in liver transplant recipients following conversion to a prolonged release tacrolimus formulation

Background

Post liver transplant diabetes mellitus (PLTDM) occurs in 10-40% of liver transplant recipients and is associated with increased morbidity and mortality. An important cause of PLTDM is tacrolimus induced, concentration-dependent, inhibition of insulin secretion.

Objective

To determine if a newly licenced formulation of tacrolimus (Envarsus-PA), which achieves peak tacrolimus concentrations 20-30% lower than other tacrolimus formulations has less of an inhibitory effect on insulin secretion.

Methods

Homeostatic model assessment (HOMA) for insulin secretion (HOMA-S) values and c-peptide levels were determined in 19 adult liver transplant recipients while being maintained on immediate- or slow-release tacrolimus formulations and repeated a minimum of 30 days following conversion to Envarsus-PA.

Results

Insulin secretion was unchanged following conversion to Envarsus-PA (HOMA-S pre-conversion: 154 ± 133 vs. 129 ± 75, post-conversion [p = 0.32], and c-peptide levels; 1059 ± 602 and 934 ± 463 respectively, p = 0.42). Fasting blood glucose (FBG) and hemoglobin A1c (HbA1c) levels were also unchanged (FBG 5.7 ± 0.8 pre-conversion vs. 5.6 ± 0.7 post-conversion; p = 0.36 and HbA1c 4.9±1.2 pre-conversion versus 5.5±0.2 post-conversion, p = 0.34).

Conclusions

Envarsus-PA had no significant effect on insulin secretion or glucose homeostasis beyond that associated with other tacrolimus formulations in adult liver transplant recipients.

Hyperglycemia and Hyperlipidemia with Kidney or Liver Transplantation: A Review

Although solid organ transplantation in persons with diabetes mellitus is often associated with hyperglycemia, the risk of hyperlipidemia in all organ transplant recipients is often underestimated. The diagnosis of diabetes often predates transplantation; however, in a moderate percentage of allograft recipients, perioperative hyperglycemia occurs triggered by antirejection regimens. Post-transplant prescription of glucocorticoids, calcineurin inhibitors and mTOR inhibitors are associated with increased lipid concentrations. The existence of diabetes mellitus prior to or following a liver transplant is associated with shorter times of useful allograft function. A cycle involving Smad, TGF beta, m-TOR and toll-like receptors has been identified in the contribution of rejection and aging of allografts. Glucocorticoids (prednisone) and calcineurin inhibitors (cyclosporine and tacrolimus) induce hyperglycemia associated with insulin resistance. Azathioprine, mycophenolate and prednisone are associated with lipogenesis. mTOR inhibitors (rapamycin) are used to decrease doses of atherogenic agents used for immunosuppression. Post-transplant medication management must balance immune suppression and glucose and lipid control. Concerns regarding rejection often override those relative to systemic and organ vascular aging and survival. This review focuses attention on the underlying mechanism of relationships between glycemia/lipidemia control, transplant rejection and graft aging.

Long-Term Survival and Induction of Operational Tolerance to Murine Islet Allografts by Co-Transplanting Cyclosporine A Microparticles and CTLA4-Ig

One strategy to prevent islet rejection is to create a favorable immune-protective local environment at the transplant site. Herein, we utilize localized cyclosporine A (CsA) delivery to islet grafts via poly(lactic-co-glycolic acid) (PLGA) microparticles to attenuate allograft rejection. CsA-eluting PLGA microparticles were prepared using a single emulsion (oil-in-water) solvent evaporation technique. CsA microparticles alone significantly delayed islet allograft rejection compared to islets alone (p < 0.05). Over 50% (6/11) of recipients receiving CsA microparticles and short-term cytotoxic T lymphocyte-associated antigen 4-Ig (CTLA4-Ig) therapy displayed prolonged allograft survival for 214 days, compared to 25% (2/8) receiving CTLA4-Ig alone. CsA microparticles alone and CsA microparticles + CTLA4-Ig islet allografts exhibited reduced T-cell (CD4+ and CD8+ cells, p < 0.001) and macrophage (CD68+ cells, p < 0.001) infiltration compared to islets alone. We observed the reduced mRNA expression of proinflammatory cytokines (IL-6, IL-10, INF-γ, and TNF-α; p < 0.05) and chemokines (CCL2, CCL5, CCL22, and CXCL10; p < 0.05) in CsA microparticles + CTLA4-Ig allografts compared to islets alone. Long-term islet allografts contained insulin+ and intra-graft FoxP3+ T regulatory cells. The rapid rejection of third-party skin grafts (C3H) in islet allograft recipients suggests that CsA microparticles + CTLA4-Ig therapy induced operational tolerance. This study demonstrates that localized CsA drug delivery plus short-course systemic immunosuppression promotes an immune protective transplant niche for allogeneic islets.

Early retinal neurovascular findings in post-transplant diabetes mellitus patients without clinical signs of diabetic retinopathy

BACKGROUND

Post-transplant diabetes mellitus (PTDM) is a specific subtype of diabetes with an uncertain impact on mortality and morbidity in post-transplant patients. Diabetic retinopathy is the most common microvascular complication of diabetes mellitus, but the long-term clinical progression in PTDM is unknown. New technologies are being used to assess pre-clinical signs of retinal changes, such as swept-source optical coherence tomography (OCT) and OCT-angiography. The aim of this study was to detect pre-clinical structural and vascular changes in the retina using swept-source-OCT and OCT-angiography in patients with PTDM.

METHODS

In this retrospective cohort study, post-kidney transplant patients were divided into PTDM and non-PTDM (control) groups. Both eyes of eligible PTDM patients and controls were included in this study. Inner retinal layer thickness was measured with swept-source-OCT. Retinal capillary density and the foveal avascular zone were measured with OCT-angiography.

RESULTS

In the PTDM group, reduced thickness was found in the inferior ganglion cell layer plus inner plexiform layer (95% CI -8.76 to -0.68; p = 0.022) and the temporal inferior segment (95% CI -10.23 to -0.76; p = 0.024) of the inner retina, as well as in the retinal nerve fiber layer in the temporal (95% CI -34.78 to -9.28 p = 0.001) and temporal inferior segments (95% CI -33.26 to -5.03 p = 0.008). No significant differences were found in the vascular capillary plexus between groups at all depths, segments, or foveal avascular zone (p = 0.088).

CONCLUSIONS

According to OCT-angiography, PTDM patients had reduced inner neurosensory retinal layers but no significant change in vascular density, which suggests that early neuroretinal degeneration might occur prior to vascular changes secondary to PTDM. Prospective studies could help elucidate the clinical course of retinal neuropathy and microvascular pathology in PTDM and provide a better understanding of PTDM complications.

The Association between CDKAL1 Gene rs10946398 Polymorphism and Post-Transplant Diabetes in Kidney Allograft Recipients Treated with Tacrolimus

Post-transplant diabetes mellitus (PTDM) is a common complication that occurs in kidney transplant patients, increasing the risk of infection, cardiovascular disease and loss of graft function. Currently, factors that increase the risk of this complication are being sought, among them polymorphisms in genes that regulate carbohydrate metabolism and influence pancreatic β-cell function. The aim of this study was to evaluate the association of selected polymorphisms of genes affecting carbohydrate metabolism, such as CDKAL1 rs10946398, GCK rs1799884, GCKR rs780094 and DGKB/TMEM195 rs2191349, with the development of post-transplant diabetes in kidney transplant patients. This study included 201 Caucasian patients after kidney transplantation treated with tacrolimus. An association was observed between the CDKAL1 rs10946398 gene polymorphism and PTDM. Among patients with PTDM, there was an increased prevalence of the CC genotype in the PTDM group compared to the group without PTDM. The chance of PTDM in those with the CC genotype was 2.60 times higher compared to those with the AC + AA genotypes (CC vs. AC + AA OR (95% CI): 2.60 (1.02-6.61), p = 0.040). Multivariate logistic regression analysis showed that advanced age and the CC genotype (rare homozygote) of CDKAL1 rs10946398 were risk factors for the development of PTDM at 1 year after transplantation. There was no statistically significant association between GCK rs1799884, GCKR rs780094 or DGKB/TMEM195 rs2191349 polymorphisms and the development of post-transplant diabetes mellitus in kidney transplant patients. The results of this study suggest that the CDKAL1 rs10946398 CC genotype is associated with the increased risk of PTDM development in patients after kidney graft transplantation treated with tacrolimus.

A comprehensive update of the metabolic and toxicological considerations for immunosuppressive drugs used during pancreas transplantation

INTRODUCTION

Despite significant advancements in immunosuppressive regimens and surgical techniques, the prevalence of adverse events related to immunosuppression remains a major challenge affecting the long-term survival rates of pancreas and kidney allografts.

AREAS COVERED

This article presents a comprehensive review of the literature and knowledge (Jan/2012-Feb/2023) concerning glucose metabolism disorders and nephrotoxicity associated with tacrolimus and mammalian target of rapamycin inhibitors (mTORi). Novel signaling pathways potentially implicated in these adverse events are discussed. Furthermore, we extensively examine the findings from clinical trials evaluating the efficacy and safety of tacrolimus, mTORi, and steroid minimization.

EXPERT OPINION

Tacrolimus-based regimens continue to be the standard treatment following pancreas transplants. However, prolonged use of tacrolimus and mTORi may lead to hyperglycemia and nephrotoxicity. Understanding and interpreting experimental data, particularly concerning novel signaling pathways beyond calcineurin-NFAT and mTOR pathways, can offer valuable insights for therapeutic interventions to mitigate hyperglycemia and nephrotoxicity. Additionally, critically analyzing clinical trial results can identify opportunities for personalized safety-based approaches to minimize side effects. It is imperative to conduct randomized-controlled studies to assess the impact of mTORi use and steroid-free protocols on pancreatic allograft survival. Such studies will aid in tailoring treatment strategies for improved transplant outcomes.

Palliative Role of Zamzam Water against Cyclosporine-Induced Nephrotoxicity through Modulating Autophagy and Apoptosis Crosstalk

Cyclosporine (CsA) is considered one of the main components of treatment protocols for organ transplantation owing to its immunosuppressive effect. However, its use is very restricted due to its nephrotoxic effect. ZW is an alkaline fluid rich in various trace elements and has a great ability to stimulate antioxidant processes. This study aimed to investigate the possible mitigating effect of ZW on CsA-induced nephrotoxicity and its underlying mechanisms. Forty rats were allocated into four groups (n = 10): a control group, ZW group, cyclosporine A group (injected subcutaneously (SC) with CsA (20 mg/kg/day)), and cyclosporine A+ Zamzam water group (administered CsA (SC) and ZW as their only drinking water (100 mL/cage/day) for 21 days). Exposure to CsA significantly (p < 0.001) increased the serum creatinine level, lipid peroxidation marker level (malondialdehyde; MDA), and the expression of apoptotic markers procaspase-8, caspase-8, caspase- 9, calpain, cytochrome c, caspas-3, P62, and mTOR in renal tissues. Meanwhile, it markedly decreased (p< 0.001) the autophagic markers (AMPK, ULK-I, ATag5, LC3, and Beclin-1), antiapoptotic Bcl-2, and antioxidant enzymes. Moreover, the administration of CsA caused histological alterations in renal tissues. ZW significantly (p < 0.001) reversed all the changes caused by CsA and conclusively achieved a positive outcome in restraining CsA-induced nephrotoxicity, as indicated by the restoration of the histological architecture, improvement of renal function, inhibition of apoptosis, and enhancement of autophagy via the AMPK/mTOR pathway.

Interventions Against Posttransplantation Diabetes: A Scientific Rationale for Treatment Hierarchy Based on Literature Review

Posttransplant diabetes (PTD) is a common medical complication after solid organ transplantation. Because of adverse outcomes associated with its development and detrimental impact on long-term survival, strategies to prevent or manage PTD are critically important but remain underresearched. Treatment hierarchies of antidiabetic therapies in the general population are currently being revolutionized based on cardiovascular outcome trials, providing evidence-based rationale for optimization of medical management. However, opportunities for improving medical management of PTD are challenged by 2 important considerations: (1) translating clinical evidence data from the general population to underresearched solid organ transplant cohorts and (2) targeting treatment based on primary underlying PTD pathophysiology. In this article, the aim is to provide an overview of PTD treatment options from a new angle. Rationalized by a consideration of underlying PTD pathophysiological defects, which are heterogeneous among diverse transplant patient cohorts, a critical appraisal of the published literature and summary of current research in progress will be reviewed. The aim is to update transplant professionals regarding medical management of PTD from a new perspective tailored therapeutic intervention based on individualized characteristics. As the gap in clinical evidence between management of PTD versus type 2 diabetes widens, it is imperative for the transplant community to bridge this gap with targeted clinical trials to ensure we optimize outcomes for solid organ transplant recipients who are at risk or develop PTD. This necessary clinical research should help efforts to improve long-term outcomes for solid transplant patients from both a patient and graft survival perspective.

Post-transplant diabetes mellitus in Canadian liver and renal transplant recipients

BACKGROUND: Post-transplant diabetes mellitus (PTDM) occurs in 10%-40% of liver and renal transplant recipients. Whether the risk factors for PTDM in liver and renal transplant recipients are similar and whether Indigenous Canadians, who have a high underlying prevalence of diabetes mellitus (DM), are at increased risk of developing PTDM have yet to be determined. OBJECTIVE: To describe and compare those variables associated with PTDM in adult Canadian liver and renal transplant recipients. METHODS: A retrospective chart review of adult liver and renal transplant recipients attending four transplant follow-up clinics in three Canadian provinces was undertaken. RESULTS: De novo PTDM was diagnosed in 184/905 (20.3%) liver and 179/390 (45.9%) renal transplant recipients. Older age, higher pre-transplant BMI, underlying immune-mediated liver disease, lower trough tacrolimus levels and longer duration of follow-up were independently associated with PTDM in liver transplant recipients and non-Caucasian race, higher pre-transplant BMI, and incidence of organ rejection in renal transplant recipients. Compared with Caucasians, Indigenous Canadians who had undergone renal transplantation had a significantly increased prevalence of PTDM (56.5% versus 40.0%, p = 0.035). The prevalence of PTDM in liver transplant recipients was similar in Indigenous Canadians and Caucasians (27.9% versus 20.1%, p = 0.215). CONCLUSIONS: The variables associated with PTDM differ in liver and renal transplant recipients. Compared with Caucasians, Indigenous Canadians undergoing renal transplantation are at increased risk of developing PTDM.

Delayed Hepatocellular Carcinoma Recurrence After Liver Transplantation: Comprehensive Clinical Characterization of Case Series

Purpose

Liver transplantation (LT) is the definite curative treatment for hepatocellular carcinoma (HCC), but recurrence can occur even under stringent criteria. “Delayed” HCC recurrence (>3 years after LT) is not common. Here, we present the clinical features of patients who developed delayed HCC recurrence after LT.

Patients and Methods

We reviewed the data of eligible patients from February 1999 to December 2020 from medical records.

Results

From among 195 (17%) HCC patients who received LT, 34 experienced HCC recurrence, with 5 (15%) delayed recurrence. These five explant tumors were staged T1b–T2, graded II–III, with two vascular invasion and four beyond the Milan criteria. The median time to recurrence was 6.1 years, with the longest interval being nearly 18 years. Recurrence patterns included two extrahepatic, one intrahepatic, and two mixed extrahepatic and intrahepatic recurrences. A drastic increase in serum alpha-fetoprotein levels was observed in four cases 1 year before recurrence. Management of recurrence included locoregional (surgssical resection in three, radiotherapy in three, transarterial chemoembolization in one, radiofrequency ablation in one) and systemic sorafenib use in three. Two patients died within 12–18 months, one died within 18–24 months, and two are still alive until the end of the study, with respective 13.5- and 16.5-month survival.

Conclusion

Delayed HCC recurrence could occur over 10 years. Therefore, continual surveillance for recurrence is justified, but biomarkers and intervals or intensities specific for delayed recurrence are not validated, which warrants further validation to facilitate personalized medical care.

Non-Immunologic Causes of Late Death-Censored Kidney Graft Failure: A Personalized Approach

Despite continuous advances in surgical and immunosuppressive protocols, the long-term survival of transplanted kidneys is still far from being satisfactory. Antibody-mediated rejection, recurrent autoimmune diseases, and death with functioning graft are the most frequent causes of late-kidney allograft failure. However, in addition to these complications, a number of other non-immunologic events may impair the function of transplanted kidneys and directly or indirectly lead to their failure. In this narrative review, we will list and discuss the most important nonimmune causes of late death-censored kidney graft failure, including quality of the donated kidney, adherence to prescriptions, drug toxicities, arterial hypertension, dyslipidemia, new onset diabetes mellitus, hyperuricemia, and lifestyle of the renal transplant recipient. For each of these risk factors, we will report the etiopathogenesis and the potential consequences on graft function, keeping in mind that in many cases, two or more risk factors may negatively interact together.

Cardiovascular Risk after Kidney Transplantation: Causes and Current Approaches to a Relevant Burden

Background. Cardiovascular disease is a frequent complication after kidney transplantation and represents the leading cause of mortality in this population. Material and Methods. We searched for the relevant articles in the National Institutes of Health library of medicine, transplant, cardiologic and nephrological journals. Results. The pathogenesis of cardiovascular disease in kidney transplant is multifactorial. Apart from non-modifiable risk factors, such as age, gender, genetic predisposition and ethnicity, several traditional and non-traditional modifiable risk factors contribute to its development. Traditional factors, such as diabetes, hypertension and dyslipidemia, may be present before and may worsen after transplantation. Immunosuppressants and impaired graft function may strongly influence the exacerbation of these comorbidities. However, in the last years, several studies showed that many other cardiovascular risk factors may be involved in kidney transplantation, including hyperuricemia, inflammation, low klotho and elevated Fibroblast Growth Factor 23 levels, deficient levels of vitamin D, vascular calcifications, anemia and poor physical activity and quality of life. Conclusions. The timely and effective treatment of time-honored and recently discovered modifiable risk factors represent the basis of the prevention of cardiovascular complications in kidney transplantation. Reduction of cardiovascular risk can improve the life expectancy, the quality of life and the allograft function and survival.

Stem cells differentiation into insulin-producing cells (IPCs): recent advances and current challenges

Type 1 diabetes mellitus (T1D) is a chronic disease characterized by an autoimmune destruction of insulin-producing β-pancreatic cells. Although many advances have been achieved in T1D treatment, current therapy strategies are often unable to maintain perfect control of glycemic levels. Several studies are searching for new and improved methodologies for expansion of β-cell cultures in vitro to increase the supply of these cells for pancreatic islets replacement therapy. A promising approach consists of differentiation of stem cells into insulin-producing cells (IPCs) in sufficient number and functional status to be transplanted. Differentiation protocols have been designed using consecutive cytokines or signaling modulator treatments, at specific dosages, to activate or inhibit the main signaling pathways that control the differentiation of induced pluripotent stem cells (iPSCs) into pancreatic β-cells. Here, we provide an overview of the current approaches and achievements in obtaining stem cell-derived β-cells and the numerous challenges, which still need to be overcome to achieve this goal. Clinical translation of stem cells-derived β-cells for efficient maintenance of long-term euglycemia remains a major issue. Therefore, research efforts have been directed to the final steps of in vitro differentiation, aiming at production of functional and mature β-cells and integration of interdisciplinary fields to generate efficient cell therapy strategies capable of reversing the clinical outcome of T1D.

New-Onset Diabetes Mellitus (NODM) After Liver Transplantation (LT): The Ultimate Non-diabetogenic Immunosuppressive Therapy

New-onset diabetes mellitus (NODM) is a common long-term complication after liver transplantation (LT). It is thought to be drug-induced in most cases, no matter the underlying disease that cause liver failure and indicated transplantation. Standard post-transplantation (PT) immunosuppressive regimens include prolonged use of calcineurin inhibitors (CNIs), namely tacrolimus (TAC), alongside corticosteroids to avoid acute and chronic graft rejection. This combination is well known for its diabetogenicity. Significant differences between the applied regimens stand out concerning the duration and dosages to prevent the metabolic side effects of these drugs in the long run without compromising the graft's survival. Studies were collected after an extensive research of PubMed database for this very specific topic using the following MeSH keywords in multiple combinations: "Liver Transplantation," "Diabetes Mellitus," "NODM," "Tacrolimus," "Cyclosporine A," and "Steroids." In addition, we used the same keywords for regular searches in Google Scholar. Only the relevant English human studies between 2010 and 2020 were collected except for review articles. Duplicates were eliminated using Mendeley software. Twelve relevant studies directly related to the targeted topic were collected and discussed, including five retrospective cohorts, four prospective cohorts, one clinical trial, one prospective pilot, and one case report. Their topics included primarily the factors increasing the risk of new-onset diabetes mellitus after liver transplantation (NODALT), TAC-based immunosuppression and its relative blood levels affecting the possible development of NODALT, the role of cyclosporine in substituting TAC regimen, and the effect of different steroids-avoiding protocols on the prevention of NODALT. The reviewed studies suggested that lowering the serum concentration of tacrolimus (cTAC) throughout the PT period and eliminating the corticosteroids regimen as early as possible, among other measures, can significantly impact the rate of emergence of NODM. This traditional review tackles the most recent studies about NODALT to establish a comprehensive view on this issue and guide clinicians and researchers for the safest immunosuppressive regimen to date, while maintaining a balanced metabolic profile.

Management of Diabetes in Candidates for Liver Transplantation and in Transplant Recipients

Diabetes is common in patients waitlisted for liver transplantation because of end-stage liver disease or hepatocellular cancer as well as in posttransplant phase (posttransplantation diabetes mellitus). In both conditions, the presence of diabetes severely affects disease burden and long-term clinical outcomes; careful monitoring and appropriate treatment are pivotal to reduce cardiovascular events and graft and recipients' death. We thoroughly reviewed the epidemiology of diabetes in the transplant setting and the different therapeutic options, from lifestyle intervention to antidiabetic drug use-including the most recent drug classes available-and to the inclusion of bariatric surgery in the treatment cascade. In waitlisted patients, the old paradigm that insulin should be the treatment of choice in the presence of severe liver dysfunction is no longer valid; novel antidiabetic agents may provide adequate glucose control without the risk of hypoglycemia, also offering cardiovascular protection. The same evidence applies to the posttransplant phase, where oral or injectable noninsulin agents should be considered to treat patients to target, limiting the impact of disease on daily living, without interaction with immunosuppressive regimens. The increasing prevalence of liver disease of metabolic origin (nonalcoholic fatty liver) among liver transplant candidates, also having a higher risk of noncirrhotic hepatocellular cancer, is likely to accelerate the acceptance of new drugs and invasive procedures, as suggested by international guidelines. Intensive lifestyle intervention programs remain however mandatory, both before and after transplantation. Achievement of adequate control is mandatory to increase candidacy, to prevent delisting, and to improve long-term outcomes.

Predictors of New-onset Diabetes After Kidney Transplantation During 2019-nCoV Pandemic: A Unison of Frequentist Inference and Narrow AI

BACKGROUND: New-onset diabetes after kidney transplant (NODAT) is a severe metabolic complication that frequently occurs in recipients following transplantation. AIM: The study aims to verify NODAT, compare cases and non-cases of this entity, and explore potential predictors in recipients within 1 year following kidney transplantation. METHODS: The research is a retrospective study of 90 renal transplant recipients (n = 90). Demographic factors and clinical aspects were analyzed using non-Bayesian statistics and machine learning (ML). The clinical aspects included the glycated hemoglobin (HbA1c) level, associated viral infections (hepatitis B virus [HBV], hepatitis C virus [HCV], and cytomegalovirus [CMV]), prior kidney transplant, hemodialysis status, body mass index (BMI) at transplant time, and 3 months later, primary causes of renal failure, and post-transplant therapeutics. All individuals were on cyclosporine and prednisolone treatment. RESULTS: The mean age was 39 (±1.5) years; recipients included 27 females (30%) and 63 males (70%). Donor type was live related (16, 17.8%) or live unrelated (74, 82.2%); 27 recipients (30%) had O+ blood group, while 70% belonged to other groups. Thirteen recipients (14.4%) were not on dialysis. Only 32 individuals (35.6%) developed NODAT. Concerning virology, confirmed by real-time polymerase chain reaction before transplantation, 19 recipients (21.1%) were CMV positive, 9 (10%) were HCV positive, and 2 (2.2%) had HBV. CONCLUSIONS: In reconciliation with frequentist statistics, the dual ML model validated several predictors that either negatively (protective) or positively (harmful) influenced HbA1c level, the majority of which were significant at 95% confidence interval. Individuals who are HCV and CMV positive are predicted to develop NODAT. Further, older individuals, with blood group O+ve, prior history of hemodialysis, a relatively high BMI before the transplant, and receiving higher doses of prednisolone following the transplant are more likely to develop NODAT. The current study represents the first research from Iraq to explore NODAT predictors among kidney transplant recipients using frequentist statistics and artificial intelligence models.

Post-Transplantation Diabetes Mellitus in Pediatric Patients

More than 80% of pediatric solid organ transplant (SOT) recipients now survive into young adulthood and many encounter transplant-related complications. Post-transplantation diabetes mellitus (PTDM), sometimes also referred to as post-transplant diabetes or new onset diabetes after transplant, occurs in 3-20% of pediatric SOT recipients depending upon the organ transplanted, age at transplantation, immunosuppressive regimen, family history, and time elapsed since transplant. To diagnose PTDM, hyperglycemia must persist beyond the initial hospitalization for transplantation when a patient is on stable doses of immunosuppressive medications. Though standard diagnostic criteria used by the American Diabetes Association (ADA) to diagnose diabetes are employed, clinicians need to be aware of the limitations of using these criteria in this unique patient population. Management of PTDM parallels strategies used for type 2 diabetes (T2D), while also carefully considering comorbidities and potential interactions with immunosuppressive medications in these patients. In caring for patients with PTDM, it is important to be familiar with these interactions and comorbidities in order to coordinate care with the transplant team and optimize outcomes for these patients.

Posttransplant Diabetes Mellitus and Immunosuppression Selection in Older and Obese Kidney Recipients

Rationale & Objective

Posttransplant diabetes mellitus (DM) after kidney transplantation increases morbidity and mortality, particularly in older and obese recipients. We aimed to examine the impact of immunosuppression selection on the risk of posttransplant DM among both older and obese kidney transplant recipients.

Study Design

Retrospective database study.

Setting & Participants

Kidney-only transplant recipients aged ≥18 years from 2005 to 2016 in the United States from US Renal Data System records, which integrate Organ Procurement and Transplantation Network/United Network for Organ Sharing records with Medicare billing claims.

Exposures

Various immunosuppression regimens in the first 3 months after transplant.

Outcomes

Development of DM >3 months-to-1 year posttransplant.

Analytical Approach

We used multivariable Cox regression to compare the incidence of posttransplant DM by immunosuppression regimen with the reference regimen of thymoglobulin (TMG) or alemtuzumab (ALEM) with tacrolimus + mycophenolic acid + prednisone using inverse propensity weighting.

Results

12.7% of kidney transplant recipients developed posttransplant DM with higher incidences in older (≥55 years vs <55 years: 16.7% vs 10.1%) and obese (body mass index [BMI] ≥ 30 kg/m² vs BMI < 30 kg/m²: 17.1% vs 10.9%) patients. The incidence of posttransplant DM was lower with steroid avoidance [TMG/ALEM + no prednisone (8.4%) and IL2rAb + no prednisone (9.7%)] than TMG/ALEM with triple therapy (13.1%). After adjustment for donor and recipient characteristics, TMG/ALEM with steroid avoidance was beneficial for all groups [age < 55 years: adjusted HR (aHR), 0.63 (95% confidence interval [CI], 0.54-0.72); age ≥ 55 years: aHR, 0.69 (95% CI, 0.60-0.79); BMI < 30 kg/m²: aHR, 0.69 (95% CI, 0.60-0.78); BMI ≥ 30 kg/m²: aHR, 0.67 (95% CI, 0.57-0.79)]. However, IL2rAb with steroid avoidance was beneficial only for older patients (aHR, 0.76; 95% CI, 0.58-0.99) and for those with BMI < 30 kg/m² (aHR, 0.63; 95% CI, 0.46-0.87).

Limitations

Retrospective study and lacked data on immunosuppression levels.

Conclusions

The beneficial impact of steroid avoidance using tacrolimus on posttransplant DM appears to differ by patient age and induction regimen.

Diabetes Remission After Bariatric Surgery in Patients on Glucocorticoids: A Pilot Study

BACKGROUND

Diabetes mellitus type 2 (DM2) remission after bariatric surgery has long been reported in the medical literature. Glucocorticoid use is associated with weight gain and could theoretically affect diabetes remission post bariatric surgery.

OBJECTIVES

The aim is to identify remission rates of DM2 among patients using glucocorticoids after bariatric surgery and assess long-term postsurgical follow-up.

METHODS

A retrospective analysis was performed on patients who used glucocorticoids and underwent bariatric surgery at the Mayo Clinic between 2008 and 2020. Data were analyzed for 3-month, 6-month, 1-year, 2-year, and 5-year intervals for factors indicative of diabetes remission.

RESULTS

Within our retrospective search, we identified 92 patients who were on any immunosuppressant medication before surgery. Of those, 22 patients had a diagnosis of DM2 while 18 of them were concurrently on glucocorticoids. Diabetes remission occurred in 11 of the 18 DM2 patients (61.11%). There was a statistically significant negative correlation between diabetes remission and combination therapy with glucocorticoids and tacrolimus (P=0.016); patients with a longer duration of DM2 diagnosis (P=0.024), and patients who used insulin three months after the procedure (P=0.001). However, percent total weight loss and the number of preoperative oral DM2 medications were not associated with worse outcomes.

CONCLUSIONS

Patients who use systemic glucocorticoids are able to achieve diabetes remission after bariatric surgery. Concurrent therapy with tacrolimus is associated with worse remission outcomes.

Adverse Effects of Immunosuppression: Nephrotoxicity, Hypertension, and Metabolic Disease

The use of Immunosuppression has led to the tremendous improvement in graft survival. However, immunosuppressants have been found to cause a variety of metabolic derangements including but not limited to: insulin resistance and diabetes, hyperlipidemia, hypertension, and weight gain after transplantation. This combination of metabolic risk factors may be associated with increased cardiovascular disease (Grundy et al., Circulation 112(17):2735, 2005). In addition many transplant recipients may have many of these risk factors pre-transplant that are exacerbated by immunosuppression. These facts emphasize the need for rigorous follow-up and management of these risk factors post-transplant.The most common immune suppressant regimens may include different combinations of these agents: Corticosteroids, Calcineurin inhibitors (CNIs), Mammalian Target of Rapamycin (mTOR) Inhibitors, Antimetabolite.

Old and New Calcineurin Inhibitors in Lupus Nephritis

Calcineurin inhibitors (CNIs) are drugs that inhibit calcineurin, a key phosphatase that dephosphorylates a transcription factor called the nuclear factor of activated T cells (NFAT), allowing its translocation into the nucleus of quiescent T cells. In the nucleus, NFAT activates interleukin 2, which stimulates the proliferation and differentiation of T-cells. CNIs can also stabilize the actin cytoskeleton of podocytes reducing proteinuria. Thanks to these characteristics, CNIs have been often used in the treatment of autoimmune diseases. However, the therapeutic index of CNIs is narrow, and their interactions with other drugs can increase toxicity or reduce efficacy. In lupus nephritis, cyclosporine and tacrolimus have been used both in induction and maintenance therapies. Observational studies and randomized controlled trials showed that both cyclosporine and tacrolimus can increase efficacy. Tolerance is satisfactory if low doses are used and the patient is carefully monitored. More recently, a new CNI, called voclosporin (VCS), has been approved by the Food and Drug Administration for use in lupus nephritis. VCS offers potential advantages over other CNIs. In two large multiethnic trials, VCS was not associated with adverse renal and metabolic events and obtained positive results despite a novel and rapid corticosteroid tapering regime.

Beta-Cell Dysfunction Induced by Tacrolimus: A Way to Explain Type 2 Diabetes?

The combination of insulin resistance and β-cells dysfunction leads to the onset of type-2 diabetes mellitus (T2DM). This process can last for decades, as β-cells are able to compensate the demand for insulin and maintain normoglycemia. Understanding the adaptive capacity of β-cells during this process and the causes of its failure is essential to the limit onset of diabetes. Post-transplant diabetes mellitus (PTDM) is a common and serious disease that affects 30% of renal transplant recipients. With the exception of immunosuppressive therapy, the risk factors for T2D are the same as for PTDM: obesity, dyslipidaemia, insulin resistance and metabolic syndrome. Tacrolimus (TAC) is the immunosuppressant of choice after renal transplantation but it has the highest rates of PTDM. Our group has shown that insulin resistance and glucolipotoxicity, without favouring the appearance of apoptosis, modify key nuclear factors for the maintenance of identity and functionality of β-cells. In this context, TAC accelerates or enhances these changes. Our hypothesis is that the pathways that are affected in the progression from pre-diabetes to diabetes in the general population are the same pathways that are affected by TAC. So, TAC can be considered a tool to study the pathogenesis of T2DM. Here, we review the common pathways of β-cells dysfunction on T2DM and TAC-induced diabetes.

Pharmacokinetics of a Once Daily Tacrolimus Formulation in First Nations and Caucasian Liver Transplant Recipients

BACKGROUND

Patient ethnicity may influence the pharmacokinetics (PK) of tacrolimus. The Canadian First Nations (FN) constitute a large and increasing segment of the liver transplant population.

OBJECTIVE

To determine whether PK differences exist for a once daily, extended-release formulation of tacrolimus in FN compared to Caucasian (Cauc) liver transplant recipients.

METHODS

Following a 1:1 mg conversion from immediate- to extended-release tacrolimus and achievement of a steady state on the latter formulation, blood samples were drawn at 0, 1, 2, 4, 6, 8 and 24 hours for whole blood tacrolimus levels by commercial immunoassay. CYP3A4 and CYP3A5 allele analyses were performed by polymerase chain reactions.

RESULTS

Nineteen subjects participated in the study (7 FN and 12 Cauc). Unlike Cauc patients, post-conversion Cmin levels did not decrease and were less variable in FN patients. FN patients also had significant shorter Tmax times (1.6±0.2 hours versus 2.8±0.3 hours, p<0.05). Oral clearance, Vd, AUCs, Cmax and Cmin levels were similar in the two cohorts. CYP3A4 genotypes were C/C in both cohorts while the CYP3A5 *1/*3 allele, was present in 2/5 FN and 0/9 Cauc.

CONCLUSIONS

Conversion from immediate- to extended-release tacrolimus results in no significant decrease in Cmin levels, less variable Cmin levels and a shorter time to Tmax in FN compared to Cauc liver transplant recipients.

Avocado Seeds Relieve Oxidative Stress-Dependent Nephrotoxicity but Enhance Immunosuppression Induced by Cyclosporine in Rats

Cyclosporine A's (CsA) immunosuppressive effect makes it an ideal drug for organ transplantation. However, CsA's uses are restricted due to its side effects. We investigated the effects of avocado seed (AvS) powder on CsA-induced nephrotoxicity and immunosuppression in rats. The injection of CsA (5 mg/kg, subcutaneously, for 10 days) increased serum levels of creatinine, uric acid, and urea, and the renal levels of the malondialdehyde. It decreased creatinine clearance and the renal activity of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase) and Na⁺/K⁺ ATPase. The administration of CsA also significantly downregulated the renal expression of interferon-gamma, tumor necrosis factor-alpha, interleukin 1 beta, monocyte chemotactic protein 1, intercellular adhesion molecule-1, and vascular cell adhesion molecule 1 genes, and increased renal DNA damage. Histopathological examination confirmed the biochemical and molecular alterations that accompanied CsA nephrotoxicity. All CsA-induced deleterious effects, except immunosuppression, were ameliorated by feeding rats on a basal diet supplemented with 5% AvS powder for 4 weeks. Importantly, AvS also maximized CsA's immunosuppressive effect. These findings suggest a potential ameliorative effect of AvS on CsA-induced nephrotoxicity, and AvS enhances CsA's immunosuppressive effect. Therefore, AvS might be used in combination with CsA in transplantation treatment to relieve the CsA-induced nephrotoxicity.

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.

Systematic review and meta-analysis of post-transplant diabetes mellitus in liver transplant recipients

Post-transplant diabetes mellitus (PTDM) compromises long-term survival in liver transplant (LT) recipients. The aim of this study was to determine incidence of PTDM after LT and risk factors associated with it. A literature search was conducted, and prospective studies that reported on the incidence of PTDM in LT adult patients on tacrolimus, sirolimus, or cyclosporine were included. We performed random effects meta-analyses for the incidence of PTDM stratified by immunosuppressant and time period. Of 9817 articles identified, 26 studies were included in the qualitative analysis and 21 studies were eligible for the quantitative analysis representing 79 559 LT recipients in 32 separate treatment arms. The proportion of patients who developed PTDM by two-three years was 0.15 (95% CI: 0.10-0.24) for cyclosporine, 0.23 (95% CI: 0.14-0.36) for tacrolimus, and 0.27 (95% CI: 0.23-0.30) for sirolimus. CONCLUSION: Our results showed that sirolimus-based immunosuppression was associated with a higher incidence of PTDM than tacrolimus or cyclosporine at two-three years. However, there were only two studies that compared all three drugs which is a limitation of the study and requires more studies with patients on sirolimus. Recipient factors increasing the risk of PTDM are older age, male sex, and high BMI.

Immunosuppressive PLGA TGF-β1 Microparticles Induce Polyclonal and Antigen-Specific Regulatory T Cells for Local Immunomodulation of Allogeneic Islet Transplants

Allogeneic islet transplantation is a promising cell-based therapy for Type 1 Diabetes (T1D). The long-term efficacy of this approach, however, is impaired by allorejection. Current clinical practice relies on long-term systemic immunosuppression, leading to severe adverse events. To avoid these detrimental effects, poly(lactic-co-glycolic acid) (PLGA) microparticles (MPs) were engineered for the localized and controlled release of immunomodulatory TGF-β1. The in vitro co-incubation of TGF-β1 releasing PLGA MPs with naïve CD4⁺ T cells resulted in the efficient generation of both polyclonal and antigen-specific induced regulatory T cells (iTregs) with robust immunosuppressive function. The co-transplantation of TGF-β1 releasing PLGA MPs and Balb/c mouse islets within the extrahepatic epididymal fat pad (EFP) of diabetic C57BL/6J mice resulted in the prompt engraftment of the allogenic implants, supporting the compatibility of PLGA MPs and local TGF-β1 release. The presence of the TGF-β1-PLGA MPs, however, did not confer significant graft protection when compared to untreated controls, despite measurement of preserved insulin expression, reduced intra-islet CD3⁺ cells invasion, and elevated CD3⁺Foxp3⁺ T cells at the peri-transplantation site in long-term functioning grafts. Examination of the broader impacts of TGF-β1/PLGA MPs on the host immune system implicated a localized nature of the immunomodulation with no observed systemic impacts. In summary, this approach establishes the feasibility of a local and modular microparticle delivery system for the immunomodulation of an extrahepatic implant site. This approach can be easily adapted to deliver larger doses or other agents, as well as multi-drug approaches, within the local graft microenvironment to prevent transplant rejection.

New-Onset Diabetes after Kidney Transplantation

New-onset diabetes mellitus after transplantation (NODAT) is a frequent complication in kidney allograft recipients. It may be caused by modifiable and non-modifiable factors. The non-modifiable factors are the same that may lead to the development of type 2 diabetes in the general population, whilst the modifiable factors include peri-operative stress, hepatitis C or cytomegalovirus infection, vitamin D deficiency, hypomagnesemia, and immunosuppressive medications such as glucocorticoids, calcineurin inhibitors (tacrolimus more than cyclosporine), and mTOR inhibitors. The most worrying complication of NODAT are major adverse cardiovascular events which represent a leading cause of morbidity and mortality in transplanted patients. However, NODAT may also result in progressive diabetic kidney disease and is frequently associated with microvascular complications, eventually determining blindness or amputation. Preventive measures for NODAT include a careful assessment of glucose tolerance before transplantation, loss of over-weight, lifestyle modification, reduced caloric intake, and physical exercise. Concomitant measures include aggressive control of systemic blood pressure and lipids levels to reduce the risk of cardiovascular events. Hypomagnesemia and low levels of vitamin D should be corrected. Immunosuppressive strategies limiting the use of diabetogenic drugs are encouraged. Many hypoglycemic drugs are available and may be used in combination with metformin in difficult cases. In patients requiring insulin treatment, the dose and type of insulin should be decided on an individual basis as insulin requirements depend on the patient's diet, amount of exercise, and renal function.

Management of post-transplant diabetes: immunosuppression, early prevention, and novel antidiabetics

Post-transplant diabetes mellitus (PTDM) shows a relationship with risk factors including obesity and tacrolimus-based immunosuppression, which decreases pancreatic insulin secretion. Several of the sodium-glucose-linked transporter 2 inhibitors (SGLT2is) and glucagon-like peptide 1 receptor agonists (GLP1-RAs) dramatically improve outcomes of individuals with type 2 diabetes with and without chronic kidney disease, which is, as heart failure and atherosclerotic cardiovascular disease, differentially affected by both drug classes (presumably). Here, we discuss SGLT2is and GLP1-RAs in context with other PTDM management strategies, including modification of immunosuppression, active lifestyle intervention, and early postoperative insulin administration. We also review recent studies with SGLT2is in PTDM, reporting their safety and antihyperglycemic efficacy, which is moderate to low, depending on kidney function. Finally, we reference retrospective case reports with GLP1-RAs that have not brought forth major concerns, likely indicating that GLP1-RAs are ideal for PTDM patients suffering from obesity. Although our article encompasses PTDM after solid organ transplantation in general, data from kidney transplant recipients constitute the largest proportion. The PTDM research community still requires data that treating and preventing PTDM will improve clinical conditions beyond hyperglycemia. We therefore suggest that it is time to collaborate, in testing novel antidiabetics among patients of all transplant disciplines.

pre-existing diabetes and PTDM in kidney transplant recipients: how to handle immunosuppression

INTRODUCTION

Preexisting diabetes (PD) and post-transplant diabetes mellitus (PTDM) are common and severe comorbidities posttransplantation. The immunosuppressive regimens are modifiable risk factors.

AREAS COVERED

We reviewed Pubmed and Cochrane database and we summarize the mechanisms and impacts of available immunosuppressive treatments on the risk of PD and PTDM. We also assess the possible management of these drugs to improve glycemic parameters while considering risks inherent in transplantation.

EXPERT OPINION

PD i) increases the risk of sepsis, ii) is an independent risk factor for infection-related mortality, and iii) increases acute rejection risk. Regarding PTDM development i) immunosuppressive strategies without corticosteroids significantly reduce the risk but the price may be a higher incidence of rejection; ii) minimization or rapid withdrawal of steroids are two valuable approaches; iii) the diabetogenic role of calcineurin inhibitors(CNIs) is also well-described and is more important for tacrolimus than for cyclosporine. Reducing tacrolimus-exposure may improve glycemic parameters but also has a higher risk of rejection. PTDM risk is higher in patients that receive sirolimus compared to mycophenolate mofetil. Finally, conversion from CNIs to belatacept may offer the best benefits to PTDM-recipients in terms of glycemic parameters, graft and patient-outcomes.

[Immunosuppressive therapy as a risk factor for new-onset diabetes after transplantation]

AIM

To analyze the modes of immunosuppressive therapy as a risk factor for new-onset diabetes after transplantation (NODAT) in kidney recipients.

MATERIALS AND METHODS

The retrospective analysis included data from 1367 recipients (755 men and 612 women) who lived more than one year after NODAT and were observed at the Moscow City Nephrology Center from January 1989 to December 2018. NODAT was established for 178 (13%) patients based on criteria from the World Health Organization and the American Diabetes Association. The modes of immunosuppressive therapy using cyclosporin A (CSA), tacrolimus (Tac), mTOR inhibitors, glucocorticoids in patients with NODAT and without NODAT were evaluated. To assess the impact of risk factors, descriptive statistics methods were used, the odds ratio (OR) and the 95% confidence interval (CI) were calculated.

RESULTS

NODAT was diagnosed in 105 men and 73 women. The OR for men was 1.19 (95% CI 0.871.64), the OR for women was 0.84 (95% CI 0.611.15). At the time of transplantation, the average age of the kidney recipients in the NODAT group was higher than in the group without NODAT: 51 [43; 57] and 43 [32; 52] years, respectively (p=0.0001). Most patients with NODAT (82%) were older than 50 years, while in the group without NODAT, the proportion of patients of the same age was 48.5% (p=0.0001). Among patients without NODAT, transplantation of a kidney from a living donor was significantly more often compared with the group with NODAT+ (7.1% vs 1.1%;p=0.001). Among the recipients who received the regimen with CSA, diabetes developed in 75 (42.1%), those who received Tac in 102 (57.3%;p0.05). The chance (risk of development) of NODAT in patients receiving i-mTOR + Tac was 3.2 (95% CI 1.476.78;p=0.032), and for patients receiving i-mTOR + cyclosporin A, the chance of development NODAT was 1.95 (95% CI 0.884.35;p=0.044).

CONCLUSION

13% of recipients developed de novo kidney diabetes after allograft. Age at the time of allotransplantation, gender, as well as the use of tacrolimus in combination with i-mTOR are the most significant risk factors for the development of NODAT.

Long-term porcine islet graft survival in diabetic non-human primates treated with clinically available immunosuppressants

BACKGROUND

Although pancreatic islet transplantation is becoming an effective therapeutic option for patients with type 1 diabetes (T1D) who suffer from a substantially impaired awareness of hypoglycemia, its application is limited due to the lack of donors. Thus, pig-to-human islet xenotransplantation has been regarded as a promising alternative due to the unlimited number of "donor organs." Long-term xenogeneic islet graft survival in pig-to-non-human primate (NHP) models has mainly been achieved by administering the anti-CD154 mAb-based immunosuppressant regimen. Since the anti-CD154 mAb treatment has been associated with unexpected fatal thromboembolic complications in clinical trials, the establishment of a new immunosuppressant regimen that is able to be directly applied in clinical trials is an urgent need.

METHODS

We assessed an immunosuppressant regimen composed of clinically available agents at porcine islet transplantation in consecutive diabetic NHPs.

RESULTS

Porcine islet graft survival in consecutive diabetic NHPs (n = 7; >222, >200, 181, 89, 62, 55, and 34 days) without severe adverse events.

CONCLUSION

We believe that our study could contribute greatly to the initiation of islet xenotransplantation clinical trials.

Differential Effects of Voclosporin and Tacrolimus on Insulin Secretion From Human Islets

The incidence of new onset diabetes after transplant (NODAT) has increased over the past decade, likely due to calcineurin inhibitor-based immunosuppressants, including tacrolimus (TAC) and cyclosporin. Voclosporin (VCS), a next-generation calcineurin inhibitor, is reported to cause fewer incidences of NODAT but the reason is unclear. While calcineurin signaling plays important roles in pancreatic β-cell survival, proliferation, and function, its effects on human β-cells remain understudied. In particular, we do not understand why some calcineurin inhibitors have more profound effects on the incidence of NODAT. We compared the effects of TAC and VCS on the dynamics of insulin secretory function, programmed cell death rate, and the transcriptomic profile of human islets. We studied 2 clinically relevant doses of TAC (10 ng/mL, 30 ng/mL) and VCS (20 ng/mL, 60 ng/mL), meant to approximate the clinical trough and peak concentrations. TAC, but not VCS, caused a significant impairment of 15 mM glucose-stimulated and 30 mM KCl-stimulated insulin secretion. This points to molecular defects in the distal stages of exocytosis after voltage-gated Ca2+ entry. No significant effects on islet cell survival or total insulin content were identified. RNA sequencing showed that TAC significantly decreased the expression of 17 genes, including direct and indirect regulators of exocytosis (SYT16, TBC1D30, PCK1, SMOC1, SYT5, PDK4, and CREM), whereas VCS has less broad, and milder, effects on gene expression. Clinically relevant doses of TAC, but not VCS, directly inhibit insulin secretion from human islets, likely via transcriptional control of exocytosis machinery.

Post-transplant diabetes mellitus

Post-transplant diabetes mellitus (PTDM) is common following solid organ transplantation, and is a risk factor for graft failure and patient mortality. In addition to standard diabetes risk factors such as obesity and ethnicity, patients undergoing transplantation also have the additional risk factors of immunosuppressive agents and infections such as hepatitis C. Patients undergoing transplant assessment should be screened for diabetes. If non-diabetic, but deemed at high risk, they should be offered careful lifestyle advice to reduce risk of post-transplant weight gain and therefore reduce risk of PTDM. Hyperglycaemia in the early post-operative period should be managed ideally with insulin therapy. Once clinically stable, there may be an opportunity to reduce or stop insulin, and consider oral hypoglycaemic agents. Despite lack of evidence from randomised trials, PTDM should be actively screened for in all transplant recipients, and actively managed with structured education, screening for complications, cardiovascular risk reduction and anti-hyperglycaemic therapy.

Evaluation of Tacrolimus Trough Level in Patients Who Developed Post-transplant Diabetes Mellitus After Kidney Transplantation: A Retrospective Single-Center Study in Saudi Arabia

BACKGROUND

Post-transplant diabetes mellitus (PTDM) is a complication after kidney transplantation. Studies showed an association between high trough levels of tacrolimus FK506 and PTDM. This study aims to investigate the association between FK506 trough levels during the first year after kidney transplant and the incidence of PTDM.

METHODS

This retrospective study included adult kidney transplant patients who were not diabetic before transplantation from 2011 to 2014. The analysis evaluated FK506 trough levels at different time points post-transplant, as well as other variables to determine whether they were associated with PTDM.

RESULTS

The cumulative incidence of PTDM was 22.5% with a median time to PTDM diagnosis of 10 months. PTDM patients had higher first FK506 (ng/mL) levels (P = .001), and more patients in the PTDM group had FK506 level >10 ng/mL during the first 3 months (P = .004). After 12 months of transplant, PTDM patients had higher body mass index (BMI) 28.3 ± 6.9 kg/m² compared to non-PTDM patients 26.4 ± 6.7 kg/m² (P = .015). Binary logistic regression analysis showed that age ≥40 years (odds ratio [OR] = 2.75, P = .004), BMI ≥25 kg/m² (OR = 2.04, P = .040), and FK506 level ≥10 ng/mL during the first 3 months (OR = 2.65, P = .009) were significantly related to PTDM development.

CONCLUSION

Patients with FK506 trough level >10 ng/mL during the first 3 months after transplantation are at higher risk of PTDM, especially in patients >40 years of age and/or who are overweight. These results may strengthen the notion that there is a connection between high FK506 trough levels and PTDM development.

The tacrolimus-induced glucose homeostasis imbalance in terms of the liver: From bench to bedside

Tacrolimus (TAC), the mainstay of maintenance immunosuppressive agents, plays a crucial role in new-onset diabetes after transplant (NODAT). Previous studies investigating the diabetogenic effects of TAC have focused on the β cells of islets. In this study, we found that TAC contributed to NODAT through directly affecting hepatic metabolic homeostasis. In mice, TAC-induced hypoglycemia rather than hyperglycemia during starvation via suppressing gluconeogenetic genes, suggesting the limitation of fasting blood glucose in the diagnosis of NODAT. In addition, TAC caused hepatic insulin resistance and triglyceride accumulation through insulin receptor substrate (IRS)2/AKT and sterol regulatory element binding protein (SREBP1) signaling, respectively. Furthermore, we found a pivotal role of CREB-regulated transcription coactivator 2 (CRTC2) in TAC-induced metabolic disorders. The restoration of hepatic CRTC2 alleviated the metabolic disorders through its downstream molecules (eg, PCK1, IRS2, and SREBP1). Consistent with the findings from bench, low CRTC2 expression in graft hepatocytes was an independent risk factor for NODAT (odds ratio = 2.692, P = .023, n = 135). Integrating grafts' CRTC2 score into the clinical model could significantly increase the predictive capacity (areas under the receiver operating characteristic curve: 0.71 vs 0.79, P = .048). Taken together, in addition to its impact on pancreatic cells, TAC induces "hematogenous diabetes" via CRTC2 signaling. Liver-targeted management may be of help to prevent or heal TAC-associated diabetes.

Effect of Posttransplant Diabetes Mellitus on Graft Loss After Living-Donor Kidney Transplant at a Single Institution

BACKGROUND

This study aimed to evaluate predictive factors for graft loss in patients who received kidney transplantation (KT) from living kidney donors (LKDs) at a single institute in Japan.

METHODS

Our study focused on patients with end-stage renal disease who underwent KT from LKDs and were followed up for at least 1 year after surgery. The primary end point was graft survival (GS). GS after KT was analyzed using the Kaplan-Meier method. GS according to subgroup classification was analyzed using the log-rank test. A multivariate analysis was performed using a Cox proportional hazard model.

RESULTS

The median follow-up period was 105.5 months after KT. The 5- and 10-year GS rates were 97.8% and 96.0% in KT recipients (KTRs) without posttransplant diabetes mellitus (PTDM) and 89.9% and 63.2% in those with PTDM, respectively. The rate of graft loss was significantly higher in KTRs with PTDM than in those without PTDM (P < .001). Of the KTRs whose diabetes mellitus (DM) was cured after KT, those who underwent dialysis because of diabetic nephropathy had no graft loss. In the multivariate analysis, the serum creatinine level at 1 month after KT, PTDM, and human leukocyte antigen mismatches were significantly associated with graft loss after KT.

CONCLUSIONS

In this study, the rate of graft loss in KTRs with PTDM was significantly higher than that of KTRs without PTDM. However, among KTRs whose DM was cured after KT, those who underwent dialysis because of diabetic nephropathy had no graft loss.

Late Conversion From Calcineurin Inhibitors to Belatacept in Kidney-Transplant Recipients Has a Significant Beneficial Impact on Glycemic Parameters

Background.

Calcineurin inhibitors (CNIs) and steroids are strongly associated with new-onset diabetes after transplantation, worsening of pre-existing diabetes, and cardiovascular events. We assessed the benefit of conversion from CNI-based to belatacept-based immunosuppression in diabetic kidney-transplant (KT) recipients on glucose control and cardiovascular risk factors.

Methods.

In this retrospective, noncontrolled single-study conducted between May 2016 and October 26, 2018, we recruited KT recipients converted from CNIs to belatacept at least 6 months after KT. The primary endpoint was the evolution of hemoglobin A1c (HbA1c) between baseline and after 6 months of treatment. Secondary endpoints included modifications to antidiabetic drugs, other cardiovascular risk factors, and renal function.

Results.

One hundred and three KT recipients were included. Of these, 26 (25%) had type 2 diabetes. The patients were either receiving oral antidiabetic drugs (n = 21; 75%) or insulin therapy (n = 14; 54%). Overall HbA1c decreased significantly from 6.2 ± 1 to 5.8 ± 1%, P < 0.001. In diabetic patients, HbA1c decreased from 7.2 ± 1 to 6.5 ± 1%, P = 0.001. HbA1c significantly decreased in the subgroup of patients with new-onset diabetes after transplantation and whether diabetes was controlled at inclusion or not (ie, HA1c ≤7% or >7%). Moreover, no diabetic patient increased the number of oral antidiabetic drugs and the dose of basal insulin was not statistically different from baseline to 6 months (16 international unit at baseline and 16 international unit at 6 mo, P = 1). One patient had to start treatment by insulin pump. During follow-up, the renal function, body mass index, and hemoglobin level of all 103 patients remained stable, 2 patients presented acute cellular rejection, and no patient suffered from graft loss.

Conclusions.

A late switch from CNI to belatacept was a valuable therapeutic option for diabetic kidney recipients and substantially improved glycemic parameters.

Range of Normal Serum Aminotransferase Levels in Liver Transplant Recipients

Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) are used to monitor liver transplant recipients (LTR) but the reference range and context of its use is not well defined. We aimed to determine the healthy ranges in LTR without chronic liver disease.

METHODS

One hundred and three LTR without chronic liver disease based on serology, transient elastography with controlled attenuated parameter, and ultrasound were included. A healthy range of aminotransferases was set to 95th percentile. An updated normal aminotransferase range was used to detect recurrence in post-liver transplantation (LT) with hepatitis C virus (HCV) and nonalcoholic fatty liver disease (NAFLD).

RESULTS

The normal ALT and AST range was 0 to 57 and 0 to 54 IU/L, respectively, in LTR and was not affected by age, sex, obesity, or choice of immunosuppressant. The diagnostic performance of serum ALT and AST to detect recurrence of NAFLD by a controlled attenuated parameter was poor with area under the receiver operating characteristic curve of 0.573 (95% confidence interval 0.493, 0.655; P = .08) and 0.537 (0.456, 0.618; P = .4), respectively. In contrast, the diagnostic performance of ALT and AST to detect recurrence of HCV after LT was 0.906 (0.868, 0.944; P < .001) and 0.925 (0.890, 0.959; P < .001), respectively.

CONCLUSION

The updated aminotransferase range in LTR is higher than the general population and accurate for detecting recurrent HCV, but not NAFLD.

Hypomagnesemia is associated with new-onset diabetes mellitus following heart transplantation

BACKGROUND

Diabetes mellitus (DM) is a major cause of morbidity and mortality following heart transplantation (HT), with 21% and 35% of survivors being affected within 1 and 5 years following HT, respectively. Magnesium deficiency is common among HT patients treated with calcineurin inhibitors and is a known risk factor for DM in non-HT patients. We therefore investigated the association between serum Mg (s-Mg) levels and new-onset diabetes after transplantation (NODAT).

METHODS

Between 2002 and 2017, 102 non-DM HT patients were assessed. In accordance with the mean value of all s-Mg levels recorded during the first year post-HT, patients were divided into high s-Mg (≥ 1.8 mg/dL) and low s-Mg (< 1.8 mg/dL) groups. The endpoint was NODAT, defined according to the diagnostic criteria of the American Diabetes Association.

RESULTS

Baseline clinical and demographic characteristics for the high (n = 45) and low s-Mg (n = 57) groups were similar. Kaplan-Meier survival analysis showed that 15-year freedom from NODAT was significantly higher among patients with high vs low s-Mg (85% vs 46% log-rank test, p < 0.001). Consistently, multivariate analysis adjusted for age, gender, immunosuppression therapies, BMI and mean creatinine values in the first year post-HT, showed that low s-Mg was independently associated with a significant > 8-fold increased risk for NODAT (95% CI 2.15-32.63, p = 0.003). Stroke rate was significantly higher in patients with low s-Mg levels vs high s-Mg (14% vs 0, p = 0.025), as well as long term mortality (HR 2.6, 95% CI 1.02-6.77, p = 0.05).

CONCLUSIONS

Low s-Mg level post-HT is an independent risk factor for NODAT in HT patients. The implications of interventions, focusing on preventing or correcting low s-Mg, for the risk of NODAT and for clinical outcomes should be evaluated.

Incidence of Post-transplantation Diabetes Mellitus Within 1 Year After Kidney Transplantation and Related Factors in Korean Cohort Study

BACKGROUND

Post-transplantation diabetes mellitus (PTDM) is associated with a higher risk of mortality and graft loss. The reported incidence of PTDM after kidney transplantation (KT) varies from 10% to 74% and varies by country and ethnicity. There are few reports of nationwide cohort studies on PTDM incidence and related factors in Korea. The purpose of this study was to evaluate incidence of PTDM and related factors within 1 year after KT in Korea.

METHODS

The KoreaN cohort study for Outcome in patients With Kidney Transplantation (KNOW-KT) enrolled 1080 recipients from July 2012 to August 2016. This study included 723 recipients, excluding 273 patients with pretransplant DM and 84 patients who were lost from follow-up within 1 year after KT.

RESULTS

Among 723 recipients, 85 (11.8%) recipients were diagnosed and treated with PTDM. Recipient age, HLA mismatches, hemoglobin A1c (HbA1c), waist-hip ratio (WHR), and use of prednisolone were significantly higher in PTDM group than the nondiabetic group. In the multivariable logistic regression analysis, independent risk factors for PTDM were older recipient age, higher WHR, and HbA1c before KT.

CONCLUSION

The incidence of PTDM was 11.8% in a nationwide Korean cohort study. The factors related to the development of PTDM within 1 year after KT were older recipient age and higher WHR, and HbA1c levels before KT. In recipients with high WHR, it is important to control pretransplant abdominal obesity to prevent PTDM after KT.