Post-Transplant Diabetes Mellitus in Kidney-Transplanted Patients: Related Factors and Impact on Long-Term Outcome

Integrative analyses of 16S rDNA sequencing and serum metabolomics demonstrate significant roles for the oral microbiota and serum metabolites in post-kidney transplant diabetes mellitus

Oral microbiota and serum metabolites play crucial roles in diabetes, but their relationship with post-transplant diabetes mellitus (PTDM), a common complication post-kidney transplantation, is not well characterized. This study investigated the relationship of oral microbiota and serum metabolites with PTDM using integrative analysis of 16S rDNA sequencing and serum metabolomics. We recruited 61 kidney transplant recipients, including 30 in the PTDM group and 31 in normal glucose tolerance controls. Oral samples and serum samples were collected from all the kidney transplant patients to perform 16S rDNA sequencing and serum metabolomics analysis. We annotated 689 oral microbial species, including 134 species unique to the PTDM group and 157 species unique to the control group. PTDM group showed upregulation of 36 metabolites and downregulation of 19 metabolites. Based on the random forest machine learning algorithm, genera such as UCG-005 (AUC = 0.9355), Succinivibrio (AUC = 0.8108); Akkermansia (AUC = 0.7742), Anaerovibrio (AUC = 0.2667), and Schwartzia (AUC = 0.2667), and serum metabolites such as LPI 18:0 (AUC: 0.8086), methylglyoxal (AUC: 0.7946), Vulgarin (AUC: 0.7828), 2-mercaptobenzothiazole (AUC: 0.7591), and PI(18:0/20:3(5Z,8Z,11Z)) (AUC: 0.7419) showed high diagnostic potential and may serve as clinical biomarkers. Furthermore, clinical indicators in PTDM patients, such as creatinine, cystatin C, and urea, showed a significant association with the differential oral microbiota and serum metabolites. Dysbiosis in the oral microbiota of the PTDM patients was associated with changes in the serum metabolites and alterations in their functions. These findings provide new insights toward identifying mechanisms by which oral microbiota and serum metabolites contribute to the development of PTDM.IMPORTANCEThis study reveals an imbalance in oral microbiota in patients with post-transplant diabetes and uncovers the potential relationship between oral microbiota and serum metabolites. These findings provide new insights into the role of oral microbiota and serum metabolites in the treatment of post-transplant diabetes, offering relevant biomarkers for clinicians and future research.

Novel insights and an updated review of metabolic syndrome in immune-mediated organ transplant rejection

Metabolic syndrome (MetS) is a group of symptoms that are characterized by abnormal changes in metabolic substances such as glucose, lipids, proteins, and bile acids. MetS is a common complication after organ transplantation and can further affect the survival and physiological function of the graft by reprograming the patient's immune environment. Additionally, MetS can influence the occurrence of post-transplant complications, such as infections. In recent years, research into the epidemiology and mechanisms of MetS has grown significantly. In this review, we summarize the mechanisms of MetS after transplantation and the mechanisms of hyperglycemia, insulin resistance, hyperlipidemia, abnormal bile acids, and abnormal amino acids on the body's immune cells as related to the effect of metabolic disorders on immune rejection after liver, kidney, heart, skin and other organ transplantation. Finally, we provide an overview of current treatment strategies and offer insights into potential future therapies for managing MetS in transplant recipients.

Posttransplantation diabetes mellitus (PTDM): pharmacological aspects and genetic predispositions

Posttransplantation diabetes mellitus (PTDM) is a form of diabetes developed after solid organ or stem cell transplantation. This condition shares physiopathological traits with type 2 diabetes, including insulin resistance and β-cells dysfunction and its prevalence varies significantly based on the diagnostic criteria used. Immunosuppressive drugs directly contribute to PTDM risk through intricate impacts on glucose regulation, insulin secretion, and inflammation. In addition, modifiable and non-modifiable environmental risk factors are associated with the onset of this condition. This review aims to provide a comprehensive overview of the multifactorial nature of PTDM in order to highlight candidate genes and variants for pharmacogenetic research. An extensive literature search was conducted to identify studies on pharmacological and genetic factors influencing PTDM development. This review stresses the importance of understanding these interactions for improving PTDM management and underscores the need for further research to refine preventive approaches, ultimately enhancing patient outcomes post-transplantation.