Hypomagnesaemia, an independent risk factor for the development of post-transplant diabetes mellitus in liver and renal transplant recipients? A systematic review.

BACKGROUND: Post-transplantation diabetes mellitus (PTDM) is common after solid organ transplantation. In the past decade, there has been increasing interest in the association between hypomagnesaemia and the development of PTDM. This systematic review aimed to investigate the current knowledge regarding the association between hypomagnesaemia and PTDM in adult liver and renal transplant recipients. METHODS: A literature search of five databases, Medline, Embase, ProQuest, Scopus and Google Scholar, as well as article reference lists, was performed. Eligible studies that focused on adult liver and renal transplant recipients without pretransplantation hyperglycaemia or diabetes were included. Other eligibility criteria included quantitative studies which reported magnesium concentrations, studies with at least 6 months of follow-up, and studies published in English. The Newcastle-Ottawa Assessment Tool was used for the quality assessment. RESULTS: In total, 12 studies were included in the final analysis. Eleven focused on renal transplantation and one on liver transplantation. All studies were medium to high quality with eight out of 12 achieving the highest rating of nine. Eight studies found a negative association between either pretransplant or early post-transplant serum magnesium concentration and the risk of PTDM, three studies found no association between these two variables, and one study found a positive association between the magnesium concentration at 8 weeks after transplantation and glycosylated haemoglobin A1C. CONCLUSIONS: Further large-scale prospective studies with at least 6 months of follow-up are needed to confirm these findings, particularly in liver transplantation, to further clarify and explore the relationship between hypomagnesaemia and PTDM.

Microbial and metabolic features in renal transplant recipients with post-transplantation diabetes mellitus.

OBJECTIVE: Post-transplantation diabetes mellitus (PTDM) is a common complication in renal transplant recipients (RTRs). Gut microbiome plays important roles in a variety of chronic metabolic diseases, but its association with the occurrence and development of PTDM is still unknown. The present study integrates the analysis of gut microbiome and metabolites to further identify the characteristics of PTDM. METHODS: A total of 100 RTRs fecal samples were collected in our study. Among them, 55 samples were submitted to Hiseq sequencing, and 100 samples were used for non-targeted metabolomics analysis. The gut microbiome and metabolomics of RTRs were comprehensively characterized. RESULTS: The species Dialister invisus was significantly associated with fasting plasma glucose (FPG). The functions of tryptophan and phenylalanine biosynthesis were enhanced in RTRs with PTDM, while the functions of fructose and butyric acid metabolism were reduced. Fecal metabolome analysis indicated that RTRs with PTDM had unique metabolite distribution characteristics, and two differentially expressed specific metabolites were significantly correlated with FPG. The correlation analysis of gut microbiome and metabolites showed that gut microbiome had an obvious effect on the metabolic characteristics of RTRs with PTDM. Moreover, the relative abundance of microbial function is associated with the expression of several specific gut microbiome and metabolites. CONCLUSIONS: Our study identified the characteristics of gut microbiome and fecal metabolites in RTRs with PTDM, and we also found two important metabolites and a bacterium were significantly associated with PTDM, which might be used as novel targets in the research field of PTDM.

Association of diuretic use with increased risk for long-term post-transplantation diabetes mellitus in kidney transplant recipients.

BACKGROUND: Post-transplantation diabetes mellitus (PTDM) is a major clinical problem in kidney transplant recipients (KTRs). Diuretic-induced hyperglycaemia and diabetes have been described in the general population. We aimed to investigate whether diuretics also increase PTDM risk in KTRs. METHODS: We included 486 stable outpatient KTRs (with a functioning graft ≥1 year) without diabetes from a prospective cohort study. Participants were classified as diuretic users and non-users based on their medication use verified by medical records. RESULTS: At the baseline study, 168 (35%) KTRs used a diuretic (thiazide, n = 74; loop diuretic, n = 76; others, n = 18) and 318 KTRs did not use a diuretic. After 5.2 years [interquartile range (IQR) 4.0‒5.9] of follow up, 54 (11%) KTRs developed PTDM. In Cox regression analyses, diuretic use was associated with incident PTDM, independent of age, sex, fasting plasma glucose (FPG) and haemoglobin A1c (HbA1c) {hazard ratio [HR] 3.28 [95% confidence interval (CI) 1.84-5.83]; P <0.001}. Further adjustment for potential confounders, including lifestyle, family history of cardiovascular disease, use of other medication, kidney function, transplantation-specific parameters, BMI, lipids and blood pressure did not materially change the association. Moreover, in Cox regression analyses, both thiazide and loop diuretics associated with the development of PTDM, independent of age, sex, FPG and HbA1c [HR 2.70 (95% CI 1.24-5.29); P = 0.012 and HR 5.08 (95% CI 2.49-10.34); P <0.001), respectively]. CONCLUSIONS: This study demonstrates that diuretics overall are associated with an increased risk of developing PTDM in KTRs, independent of established risk factors for PTDM development. The association was present for both thiazide and loop diuretics.

Dynamics of glucose metabolism after liver transplantation: prediabetes as a window of opportunity for patient survival and long-term kidney function.

Post-transplantation diabetes mellitus (PTDM) is a relevant complication following liver transplantation with profound impact on morbidity and mortality. To date, little is known about the evolution and dynamics of glucose metabolism and the impact of prediabetes in long-term follow-up. To address this issue, all consecutive adult liver transplant recipients (n = 429) from a European university hospital transplant center between 2007 and 2017 were analyzed retrospectively. In patients without pre-existing diabetes (n = 327), we conducted a longitudinal characterization of glucose metabolism. Median follow-up was 37 [9-64, IQR] months. Median prevalence of prediabetes was 39 [37-39]% and of PTDM 21 [17-22]%. Throughout follow-up, intra-individual glucose regulation of patients was highly variable, continuously fluctuating between different states of glucose metabolism (normal glucose tolerance, prediabetes, PTDM). Whereas overall survival and long-term kidney function of patients with PTDM were significantly lower than that of patients with normal glucose metabolism, prediabetes was not associated with adverse outcome. This study provides new insight into the dynamics and impact of glucose metabolism after liver transplantation. Unlike PTDM, prediabetes is not associated with adverse outcome, providing a window of opportunity for targeted intervention. The results underline the need for constant screening and intervention in posttransplant care of liver allograft recipients.

Prediabetes and older age increase the risk of post-transplantation diabetes mellitus: Qatar experience.

Post-transplantation diabetes mellitus (PTDM) is a major complication in kidney transplant recipients leading to reduced allograft and patient survival. Given the high prevalence of diabetes in Qatar, which is twice the global average, we were interested in determining the incidence of PTDM, identifying risk factors, and comparing clinical outcomes in kidney transplant recipients with and without diabetes. We retrospectively followed up 191 adult kidney allograft recipients transplanted between January 1, 2012, and December 31, 2016, for a median of 41 months. A total of 76 patients (40%) had pre-existing diabetes. A total of 39 patients developed PTDM during follow-up; they represent 34% of patients who did not have diabetes prior to transplantation. Two thirds of PTDM occurred within 3-6 months post-transplantation. Prediabetes before transplant [OR = 6.07 (1.24-29.74), P = .026] older recipient's age at the time of transplantation [OR = 1.10 (1.00-1.20), P = .039] and average fasting blood sugar during 3-6 months post-transplant [OR = 1.06 (1.01-1.11), P = .010] were independently associated with PTDM. Patient and kidney allograft survival rates exceeded 97% in all groups. The incidence of PTDM in kidney transplant recipients living in Qatar is high. Older age and prediabetes are independent risk factors for developing PTDM.

Validation of diagnostic utility of fasting plasma glucose and HbA1c in stable renal transplant recipients one year after transplantation.

BACKGROUND: The use of HbA1c ≥6.5% for diagnosis of diabetes has been challenged for post-transplantation diabetes mellitus (PTDM) also known as new onset diabetes after transplantation (NODAT) due to a low sensitivity early after renal transplantation. PTDM diagnosed with an oral glucose tolerance test (OGTT) is highly predictable for long-term patient mortality. HbA1c was introduced for diagnosis based on the risk of developing diabetic retinopathy. The utility of HbA1c measures versus glucose criteria has not been widely assessed in stable transplant patients but still HbA1c is widely used in this population. The aim of the present analyses was to validate the utility of fasting plasma glucose (FPG) together with HbA1c in diagnosing PTDM in stable renal transplant recipients (RTRs). METHODS: OGTT's were performed one year after transplantation in 494 consecutive RTRs without diabetes. FPG and HbA1c were obtained the same day, before starting the OGTT. Validation was performed using C-statistics and logistic regression analyses. RESULTS: PTDM was diagnosed in 51 patients (10.3%) by glucose criteria, 38 (74%) patients were diagnosed by FPG ≥7.0 mmol/L [126.1 mg/dl], and 13 (26%) only by 2-h plasma glucose. Six of the latter had HbA1c ≥6.5%. Only seven patients out of the 51 (13.7%) PTDM patients remained undiagnosed when HbA1c ≥6.5% was used together with FPG, and five of these regressed to normal after a median follow-up of 14 months. ROC curves including FPG and HbA1c versus OGTT derived criteria revealed an AUC of 0.858. CONCLUSIONS: Combining standard diagnostic FPG and HbA1c criteria captured almost all patients with persistent PTDM in stable RTRs. The combined use of the criteria appears to be an applicable diagnostic strategy for PTDM without the need of an OGTT one year post-transplant. TRIAL REGISTRATION: Retrospectively registered.

Metabolic Complications Precede Alloreactivity and Are Characterized by Changes in Suppression of Tumorigenicity 2 Signaling.

New-onset post-transplantation diabetes mellitus (PTDM) occurs commonly after allogeneic hematopoietic cell transplantation (HCT) and is associated with inferior survival. We hypothesize that PTDM and nonrelapse mortality (NRM) are related to IL-33/suppression of tumorigenicity 2 (ST2) signaling and that soluble ST2 (sST2) levels will predict PTDM diagnosis. sST2 was measured at engraftment and day +30 in 36 euglycemic HCT recipients followed prospectively for PTDM (cohort 1). Results were confirmed in a validation cohort of 26 patients without pre-existing diabetes analyzed retrospectively for PTDM (cohort 2). Twelve patients with established diabetes before HCT were analyzed in cohort 3. When compared with recipients without PTDM, patients developing PTDM (n = 24) from cohort 1 had elevated sST2 levels at engraftment (P = .02) and at day +30 (P < .01). Cohort 2 confirmed this finding at engraftment (P = .01). Cohort 3 patients with pretransplantation diabetes had higher sST2 at engraftment than patients maintaining euglycemia after HCT from cohort 2 (P = .03). Multivariate analysis of cohorts 1 and 2 showed high engraftment sST2 predicted increased PTDM and NRM risk, independent of conditioning and grades 3 to 4 acute graft-versus-host-disease. sST2 was elevated in PTDM, indicating a relationship between glucose homeostasis and the IL-33/ST2 axis after transplantation. Correction of metabolic complications may decrease sST2 and improve NRM.

Diabetic kidney transplant recipients: Impaired infection control and increased alloreactivity.

BACKGROUND: Post-transplantation diabetes mellitus (PTDM) has been associated with inferior patient and allograft outcomes. However, previous studies did not identify differences in infection control and alloreactivity. METHODS: We studied 449 kidney transplant recipients (KTRs) between 2005 and 2013. Fifty (11.1%) KTRs were diagnosed with PTDM and 60 (13.4%) KTRs with pre-existing diabetes. Samples were collected pretransplantation, at +1, +2, +3 months post-transplantation. CMV specific and alloreactive T cells were quantified by interferon-γ Elispot assay. Lymphocyte subpopulations were quantified by flow cytometry. RESULTS: Upon multivariate analysis, age, obesity, and the use of tacrolimus increased the risk of PTDM (P<.05). KTRs with pre-existing diabetes/PTDM showed higher rates of sepsis (P<.01). Total CD3+ and CD4+ T cell counts were significantly lower in KTRs with PTDM/pre-existing diabetes post-transplantation (P<.05). No differences were observed for CMV-specific T cells between any group (P>.05). KTRs developing PTDM showed increased frequencies of alloreactive T-cells post-transplantation (P<.05). CONCLUSIONS: Our results suggest higher rates of infection in KTRs with pre-existing diabetes/PTDM that may be attributed to impaired overall immunity. Higher frequencies of alloreactive T cells contribute to inferior long-term outcomes. As acute rejection, but not pre-existing diabetes/PTDM, was associated with inferior allograft survival and function, maintaining adequate immunosuppression to prevent rejection seems important.

Post-transplantation diabetes mellitus: evaluation of treatment strategies.

BACKGROUND: Post-transplantation diabetes mellitus (PTDM) is a serious complication after kidney transplantation, but evidence regarding long-term outcomes of treatment regimens remains scarce. AIM AND METHODS: The aim of this retrospective cohort analysis was to assess the long-term efficiency and safety of antidiabetic treatments in kidney transplant recipients (KTRs), who were diagnosed with PTDM by an oral glucose tolerance test (OGTT). RESULTS: Of 561 KTRs that were screened for PTDM at our outpatient clinic, 71 (13%) had a diabetic OGTT and were included in this study. Mean follow-up was 34.2 ± 16.1 months. Thirty-six PTDM patients (51%) received antidiabetic treatment after diagnosis with either a dipeptidyl peptidase-4 (DPP-4) inhibitor, a sulfonylurea, pioglitazone, or insulin. These patients had significantly higher fasting glucose and two-h plasma glucose (2HPG) values at baseline than those who remained without therapy. In contrast to lifestyle modification alone or sulfonylureas, DPP-4 inhibitors improved glycemic control significantly. Adverse events were generally mild and occurred at similar rates in all groups. CONCLUSION: While sulfonylureas failed to improve glycemic control, DPP-4 inhibitors appeared effective and safe for the therapy of PTDM after kidney transplantation.

Computed tomography-based intermuscular adipose tissue analysis and its predicting role in post-kidney transplantation diabetes mellitus.

BACKGROUND: While body mass index (BMI) is the most widely used indicator as a measure of obesity factors in post-transplantation diabetes mellitus (PTDM), body composition is a more accurate measure of obesity. This study aims to investigate the effects of Computed tomography (CT)--based morphemic factors on PTDM and establish a prediction model for PTDM after kidney transplantation. METHODS: The pre-transplant data and glycemic levels of kidney transplant recipients (June 2021 to July 2023) were retrospectively and prospectively collected. Univariate and multivariate analyses were conducted to analyze the relationship between morphemic factors and PTDM at one month, six months, and one year after hospital discharge. Subsequently, a one-year risk prediction model based on morphemic factors was developed. RESULTS: The study consisted of 131 participants in the one-month group, where Hemoglobin A1c (HbA1c) (p = 0.02) was identified as the risk factor for PTDM. In the six-month group, 129 participants were included, and the intermuscular adipose tissue (IMAT) area (p = 0.02) was identified as the risk factor for PTDM. The one-year group had 128 participants, and the risk factors for PTDM were identified as body mass index (BMI) (p = 0.02), HbA1c (p = 0.01), and IMAT area (p = 0.007). HbA1c (%) and IMAT area were included in the risk prediction Model for PTDM in the one-year group with AUC = 0.716 (95 % CI 0.591-0.841, p = 0.001). CONCLUSIONS: Compared to BMI and other morphemic factors, this study demonstrated that the IMAT area was the most potential predictor of PTDM. CLINICAL TRIAL NOTATION: Chictr.org (ChiCTR2300078639).

SGLT2 inhibitors in diabetic and non-diabetic kidney transplant recipients: current knowledge and expectations.

The beneficial effect of sodium-glucose cotransporter-2 inhibitors (SGLT2i) have been shown recently in numerous randomized controlled trials (RCT) and systematic reviews. According to KDIGO guidelines, SGLT2i currently represent a first choice for diabetic patients with chronic kidney disease (CKD). In addition, a recent meta-analysis of 13 large led by the 'SGLT2 inhibitor Meta-Analysis Cardio-Renal Trialists' Consortium' (SMART-C) provided solid evidence of SGLT2i beneficial effects in CKD or in patients with heart failure, with and without diabetes. Collectively, the patients treated with SGLT2i had a decreased risk of CKD progression, acute kidney injury (AKI), end-stage kidney disease (ESKD) or death from heart failure. Whether these cardio-renal benefits should be extrapolated to kidney transplant recipients (KTR) needs to be assessed in further studies. In this article, we report recent data accumulated so far in the literature, looking at the efficacy and safety of SGLT2i in diabetic and non-diabetic KTR. We found encouraging data regarding the use of SGLT2i in KTR with diabetes. These agents appeared to be safe, and they reduced body weight and blood pressure in this group of patients. Potential effects on kidney graft function and survival are yet to be investigated.

Indirect Insulin Resistance Indices and Their Cut-Off Values for the Prediction of Post-Transplantation Diabetes Mellitus in Kidney Transplant Recipients.

BACKGROUND: Insulin resistance plays an important role in the development of post-transplantation diabetes mellitus (PTDM) in kidney transplant recipients (KTRs). Current methods for the direct determination of insulin resistance are complicated and invasive. Therefore, this study aimed to investigate the relevance of indirect insulin resistance indices in relation to the development of PTDM in KTRs. METHODS: We included 472 stable outpatient KTRs without diabetes at baseline from a prospective cohort study. Four indirect insulin resistance indices, namely homeostasis model assessment-insulin resistance (HOMA-IR), visceral adiposity index (VAI), lipid accumulation product (LAP), and triglycerides-glucose (TyG) index, were assessed. We analyzed each measure using the receiver operating characteristic (ROC) curve for PTDM development. The optimal cut-off value for each parameter was determined using the Youden index. RESULTS: After a median of 9.6 years (interquartile range (IQR) 6.6-10.2) of follow-up, 68 (14%) KTRs developed PTDM. In Cox regression analyses, all indirect insulin resistance indices associated with incident PTDM were independent of potential confounders. ROC curve was 0.764 (95% CI, 0.703-0.826) for HOMA-IR, 0.685 (95% CI, 0.615-0.757) for VAI, 0.743 (95% CI, 0.678-0.808) for LAP, and 0.698 (95% CI, 0.629-0.766) for TyG index, with respective optimal cut-off values of 2.47, 4.01, 87.0, and 4.94. CONCLUSIONS: Indirect insulin resistance indices can be used to predict incident PTDM in KTRs. In addition to HOMA-IR, insulin-free surrogates of insulin resistance might serve as useful methods to identify KTRs at risk of PTDM, thus obviating the necessity to measure insulin.

Impaired TFEB activation and mitophagy as a cause of PPP3/calcineurin inhibitor-induced pancreatic ß-cell dysfunction.

Macroautophagy/autophagy or mitophagy plays crucial roles in the maintenance of pancreatic ß-cell function. PPP3/calcineurin can modulate the activity of TFEB, a master regulator of lysosomal biogenesis and autophagy gene expression, through dephosphorylation. We studied whether PPP3/calcineurin inhibitors can affect the mitophagy of pancreatic ß-cells and pancreatic ß-cell function employing FK506, an immunosuppressive drug against graft rejection. FK506 suppressed rotenone- or oligomycin+antimycin-A-induced mitophagy measured by Mito-Keima localization in acidic lysosomes or RFP-LC3 puncta colocalized with TOMM20 in INS-1 insulinoma cells. FK506 diminished nuclear translocation of TFEB after treatment with rotenone or oligomycin+antimycin A. Forced TFEB nuclear translocation by a constitutively active TFEB mutant transfection restored impaired mitophagy by FK506, suggesting the role of decreased TFEB nuclear translocation in FK506-mediated mitophagy impairment. Probably due to reduced mitophagy, recovery of mitochondrial potential or quenching of mitochondrial ROS after removal of rotenone or oligomycin+antimycin A was delayed by FK506. Mitochondrial oxygen consumption was reduced by FK506, indicating reduced mitochondrial function by FK506. Likely due to mitochondrial dysfunction, insulin release from INS-1 cells was reduced by FK506 in vitro. FK506 treatment also reduced insulin release and impaired glucose tolerance in vivo, which was associated with decreased mitophagy and mitochondrial COX activity in pancreatic islets. FK506-induced mitochondrial dysfunction and glucose intolerance were ameliorated by an autophagy enhancer activating TFEB. These results suggest that diminished mitophagy and consequent mitochondrial dysfunction of pancreatic ß-cells contribute to FK506-induced ß-cell dysfunction or glucose intolerance, and autophagy enhancement could be a therapeutic modality against post-transplantation diabetes mellitus caused by PPP3/calcineurin inhibitors.

Postoperative fasting plasma glucose and family history diabetes mellitus can predict post-transplantation diabetes mellitus in kidney transplant recipients.

PURPOSE: To explore whether glycated albumin (GA) or fasting plasma glucose (FPG), both routinely monitored during patients' hospital stay, can be used to predict post-transplantation diabetes mellitus (PTDM). METHODS: All kidney transplantation recipients (KTRs) from January 2017 to December 2018 were followed-up for 1 year. PTDM was diagnosed from day 45 post-operation to 1 year. When the completeness was above 80%, FPG or GA data on the day was selected, analyzed, and presented as range parameters and standard deviation (SD) and compared between PTDM and non-PTDM groups in fluctuation and stable periods. The predictive cut-off values were determined via receiver operating characteristic (ROC) analysis. The PTDM combined predictive mode, formed by the independent risk factors derived from logistic regression analyses, was compared with each independent risk factor with the independent ROC curve test. RESULTS: Among 536 KTRs, 38 patients developed PTDM up to 1 year post-operatively. The family history diabetes mellitus (OR, 3.21; P = 0.035), the FPG SD in fluctuation period >2.09 mmol/L (OR, 3.06; P = 0.002), and the FPG maximum in stable period >5.08 mmol/L (OR, 6.85; P < 0.001) were the PTDM independent risk factors. The discrimination of the combined mode (area under the curve = 0.81, sensitivity = 73.68%, and specificity = 76.31%) was higher than each prediction (P < 0.05). CONCLUSIONS: The FPG standard deviation during the fluctuation period, FPG maximum during the stable period, and family history diabetes mellitus predicted PTDM with good discrimination and potential routine clinical use.

Progress of new-onset diabetes after liver and kidney transplantation.

Organ transplantation is currently the most effective treatment for end-stage organ failure. Post transplantation diabetes mellitus (PTDM) is a severe complication after organ transplantation that seriously affects the short-term and long-term survival of recipients. However, PTDM is often overlooked or poorly managed in its early stage. This article provides an overview of the incidence, and pathogenesis of and risk factors for PTDM, aiming to gain a deeper understanding of PTDM and improve the quality of life of recipients.

A Randomized Controlled Trial on Safety of Steroid Avoidance in Immunologically Low-Risk Kidney Transplant Recipients.

INTRODUCTION: Steroid-based immunosuppression after transplantation increases the risk of post-transplant diabetes mellitus (PTDM), with adverse effects on patient and graft survival. In the SAILOR study, we investigated the safety and efficacy of complete steroid avoidance in immunologically low-risk kidney recipients without diabetes on the current standard-of-care maintenance regimen with tacrolimus/mycophenolate mofetil (MMF). METHODS: In this 2-year, multicenter, open-label trial, a total of 222 patients were randomized to receive either steroid avoidance protocol (tacrolimus/MMF/antithymocyte globulin [ATG] induction [n = 113]) or steroid maintenance protocol (tacrolimus/MMF/prednisolone/basiliximab-induction [n = 109]). RESULTS: At 1 year, no significant differences were found between steroid avoidance and steroid maintenance arms in the incidence of PTDM, the primary end point (12.4% vs. 18.3%, respectively, P = 0.30, CI: 16.3-4.4), or in overall biopsy-proven rejections (15% vs. 13.8%, respectively, P = 0.85). At 2 years, the composite end point of freedom from acute rejection, graft loss, and death (81% vs. 85%, respectively, P = 0.4), kidney function, or adverse events was comparable between the 2 arms. Moreover, 63.9% of the patients in the steroid avoidance arm remained free from steroids at 2 years. CONCLUSION: The SAILOR study provides further evidence for the feasibility, safety, and efficacy of early steroid-free treatment at 2 years in immunologically low-risk kidney recipients with tacrolimus/MMF maintenance regimen.

Optimal use of SGLT2 inhibitors in diabetic kidney transplant recipients.

Sodium-glucose cotransporter 2 inhibitor (SGLT2i), a glucosuric agent initially approved for use as an antidiabetic agent, was unexpectedly found to confer cardio-and reno-protective effects in individuals with or without type 2 diabetes mellitus. Despite mounting evidence suggesting that SGLT2i provides cardio- and reno-protective benefits in both diabetic and non-diabetic and in chronic kidney disease (CKD) patients in the general population, reservations for its use in the transplant setting persist due to concerns for increased risk of genital mycotic and urinary tract infections. A comprehensive review of the literature on the efficacy and safety of SGLT2i use in diabetic kidney transplant recipients is herein presented followed by authors' opinion on its optimal use in this patient population.

Tacrolimus inhibits insulin release and promotes apoptosis of Min6 cells through the inhibition of the PI3K/Akt/mTOR pathway.

As a calcineurin inhibitor, tacrolimus is commonly used as a first­line immunosuppressant in organ transplant recipients. Post­transplantation diabetes mellitus (PTDM) is a common complication following kidney transplantation and is associated with immunosuppressant drugs, such as tacrolimus. PTDM caused by tacrolimus may be related to its influence on insulin secretion and insulin resistance. However, the specific mechanism has not been fully elucidated. The aim of the present study was to investigate whether the PI3K/Akt/mTOR signaling pathway served an important role in the pathogenesis of PTDM induced by tacrolimus. In the present study, the Cell Counting Kit­8 assay was used to measure the effect of tacrolimus on the viability of Min6 mouse insulinoma cells. The effects of tacrolimus on the insulin secretion and the activity of caspase­3 of Min6 cells stimulated by glucose exposure were measured by ELISA. Superoxide dismutase (SOD) and malondialdehyde (MDA) levels were measured using WST­8 and thiobarbituric acid assays, respectively. The effects of tacrolimus on the mRNA expression levels of PI3K, Akt and mTOR were detected by reverse transcription­quantitative PCR (RT­qPCR), whereas the protein expression levels of PI3K, Akt, mTOR, phosphorylated (p)­AKT and p­mTOR in Min6 cells were assessed using western blotting. The present data indicated that, compared with the control group, 5, 25 and 50 ng/ml tacrolimus treatment could inhibit the insulin secretion of Min6 cells stimulated by glucose solution, and 50 ng/ml tacrolimus could notably decrease the stimulation index (P<0.05). Moreover, 50 ng/ml tacrolimus markedly increased the activity of caspase­3 by 175.1% (P<0.05), it also decreased the SOD activity (P<0.01) and increased MDA levels (P<0.05). The RT­qPCR results demonstrated that the mRNA expression levels of PI3K, Akt and mTOR were downregulated by 25 and 50 ng/ml tacrolimus (P<0.01). Furthermore, the western blotting results suggested that tacrolimus had no significant effects on the expression levels of total PI3K, Akt and mTOR proteins (P>0.05), but 25 and 50 ng/ml tacrolimus could significantly inhibit the expression levels of p­Akt and p­mTOR (P<0.01). In conclusion, tacrolimus decreased the activity and insulin secretion of pancreatic ß cells and induced the apoptosis of islet ß cells by inhibiting the mRNA expression levels of PI3K, Akt and mTOR and reducing the phosphorylation of Akt and mTOR proteins in the PI3K/Akt/mTOR signaling pathway, which may ultimately lead to the occurrence of diabetes mellitus, and may be considered as one of the specific mechanisms of PTDM caused by tacrolimus.

New-onset post-transplant diabetes mellitus after haploidentical hematopoietic cell transplant with post-transplant cyclophosphamide.

Haploidentical hematopoietic cell transplant (haplo-HCT) with post-transplant cyclophosphamide (PTCY) is utilized for patients with hematological disorders but without conventional donors. The effects of new-onset post-transplant diabetes mellitus (PTDM) following haplo-HCT are unknown. We examined PTDM incidence and outcomes after haplo-HCT with PTCY. Patients without diabetes receiving haplo-HCT (n=64) were analyzed for PTDM diagnosis (defined as blood glucose≥ 200 mg/dL). By day 100, 14 (22%) patients developed PTDM (median, 18 days). Hyperglycemia (blood glucose ≥ 200 mg/dL) preceded corticosteroids in 11 (79%) individuals. PTDM patients had increased death/relapse (p=0.029). PTDM occurs frequently, precedes corticosteroids, and leads to inferior outcomes following haplo-HCT. PTDM prophylaxis/treatment may improve HCT survival.

Pretransplant metabolic syndrome and its components predict post-transplantation diabetes mellitus in Chinese patients receiving a first renal transplant.

BACKGROUND: Post-transplantation diabetes mellitus (PTDM) remains a major clinical challenge following renal transplant. Identification of pretransplant modifiable risk factors may allow timely interventions to prevent PTDM. This study aims to determine whether pretransplant metabolic syndrome and its components are able to predict PTDM in Chinese patients receiving their first renal transplant. PATIENTS AND METHODS: We conducted a single-center retrospective study of 633 non-diabetic patients receiving a first kidney transplant. PTDM was diagnosed between 1 month and 1 year post-transplant. Multivariable logistic regression and Cox proportional hazards model were applied to detect potential pretransplant risk factors for PTDM. RESULTS: One year post-transplant, 26.2% of recipients had developed PTDM. PTDM patients had significantly higher fasting plasma glucose (FPG) (P=0.026) and body mass index (BMI) (P=0.006) than non-PRDM patients, and lower levels of high-density lipoprotein cholesterol (P=0.015). The presence of metabolic syndrome was an independent risk factor for PTDM, as assessed by multivariable logistic regression analysis (OR 1.28, 95% CI 1.04-1.51, P=0.038) and Cox proportional hazards model (OR 2.75, 95% CI 1.45-6.05, P=0.021). Moreover, both FPG >5.6 mmol/L and BMI >28 kg/m2 (obesity) were able to predict PTDM. CONCLUSION: Our results suggest that the presence of metabolic syndrome and its components, impaired fasting glycemia and obesity, are independent risk factors for PTDM in Chinese non-diabetic patients receiving a first renal transplant. Interventions aimed at improving pretransplant metabolic syndrome may reduce the incidence of PTDM.