Diabetic Nephropathy - possibilities of early laboratory diagnostics and course prediction (review of literature)

The medical and social significance of diabetes mellitus is determined by a progressive increase in the incidence of the disease, as well as the development of disabling and reducing the quality of life of macro- and microvascular complications in patients of working age, in particular, with the development of diabetic nephropathy (DN), which develops in one third of patients with type 1 and 2 diabetes. DN is the third leading cause of death after diseases of the cardiovascular system and oncological pathologies. In this regard, the identification of DN at the early stages is an important task both from the standpoint of prevention and a more favorable prognosis of the course of diabetes. This review presents data on the possibilities of early diagnosis of DN using blood and urine biomarkers, as well as information on their diagnostic and prognostic value. The analysis of the interpretation of the indicator of microalbuminuria in type 1 and 2 diabetes was carried out. In addition, the literature data of recent years on the informative value of determining markers of podocyte damage, on the role of oxidative stress products, immune-inflammatory factors, and vascular endothelial growth factor in the process of the onset and development of DN are presented. The possibility of their practical use for the diagnosis of DN in clinical practice is discussed. The literature search for this review was carried out using the databases of the RSCI, CyberLeninka, Scopus, Web of Science, MedLine, PubMed for the period from 2011 to 2021. using the following keywords: diabetes mellitus, diabetic nephropathy, markers of diabetic nephropathy; kidney damage, early diagnosis of diabetic nephropathy.

Short-term renal and metabolic effects of low dose vildagliptin treatment added-on insulin therapy in non-proteinuric patients with type 2 diabetes: open-label randomized prospective study

Objective The aim of this randomized comparative study was to assess renal and metabolic effects of vildagliptin in insulin-treated type 2 diabetes (T2DM) patients without overt chronic kidney disease. Subjects and methods We randomized 47 insulin-treated non-proteinuric patients with satisfactory controlled T2DM and estimated glomerular filtration rate (eGFR) ≥ 60 mL/min/1.73m 2 either to continue insulin therapy (control) or to receive combined insulin-vildagliptin treatment (VIG group). We assessed eGFR using serum creatinine (eGFRcreat), cystatin C (eGFRcys), and both (eGFRcreat-cys), and urinary creatinine-adjusted excretion of albumin (UACR), type IV collagen (uCol IV/Cr), and neutrophil gelatinase-associated lipocalin (uNGAL/Cr) at baseline and after 6 months of treatment. Results Study groups were comparable in terms of age and sex (60.1 ± 6.1 years and 42.9% men in control group vs. 60.8 ± 5.2 years and 39.1% in VIG group). After 6 months of treatment, there were no significant changes in main assessed parameters in control group. VIG group demonstrated significant decrease in HbA1c, diastolic blood pressure, frequency of hypoglycemia, and high-sensitivity C-reactive protein level as compared to the changes in control group. While eGFRcreat, UACR, and uNGAL/Cr showed no significant changes after vildagliptin addition, eGFRcys, eGFRcreat-cys, and uCol IV/Cr changed significantly in comparison with control group (+7.0% [3.7;13.3]; +5.1% [1.4;8.5]; -32,8% [-55.8;-24.4], respectively, p < 0.01 each). Correlation and regression analysis revealed glucose-independent pattern of these changes. Conclusion Addition of vildagliptin to ongoing insulin therapy in patients with T2DM was associated with a reduction in uCol IV/Cr and an increase in eGFRcys and eGFRcreat-cys, independent of T2DM control parameters.

Renal effects of glucagon-like peptide receptor agonists in patients with type 1 diabetes mellitus

AIM

The purpose of our study is to assess the effects of glucagon-like peptide-1 receptor agonists (GLP-1R agonists) on early markers of kidney damage in patients with type 1 diabetes mellitus (DM).

MATERIALS AND METHODS

The study included 27 patients with type 1 diabetes with normo- (n=16) and microalbuminuria (n=11) on intensive insulin injection regimen with insulin analogs. Patients were divided into two groups: 15 patients continued insulin therapy throughout the follow-up period, 12 patients were given 1.2 mg GLP-1R agonist (Liraglutide) once a day in addition to the insulin therapy for 6 months. HbA1c, lipid profile, classic markers of kidney damage (albuminuria, creatinine, glomerular filtration rate); plazma (neutrophilic gelatinase-associated lipoxalin - NGAL, molecule renal damage of type 1 - KIM-1, cystatin C, osteopontin) and urinary kidney biomarkers (nephrin, podocyne, uromodulin, NGAL, KIM-1, collagen type IV, cystatin C) were evaluated prior and in dynamics at 6 months. Kidney biomarkers levels were assessed by the enzyme-linked immunosorbent assay (ELISA).

RESULTS

We observed a significant decrease in the urinary excretion of type IV collagen, cystatin C, increased uromodulin excretion and decrease in the plasma levels of osteopontin, NGAL and cystatin C in the group of combined insulin and GLP-1R agonist therapy.

CONCLUSION

Changes in the level of sensitive kidney biomarkers indicate a possible renoprotective effect of GLP-1R agonist therapy in patients with type 1 diabetes at an early stages of kidney damage.