Tom 1 (2021): Zeszyt 1 (June 2021)

Diabetic kidney disease (DKD) is characterized by an accumulation of extracellular matrix proteins such as collagen and fibronectin in the kidney, resulting in tubulointerstitial fibrosis, glomerular mesangial hypertrophy and expansion, thickening of the glomerular basement membrane, podocyte foot process effacement, and inflammation due to the infiltration of monocytes and macrophages. All of these factors contribute to kidney function loss and can ultimately lead to progressive chronic kidney disease and kidney failure. In the review, we summarize the current state of knowledge in the pathogenesis of diabetic kidney disease to include the impact of genetic and environmental factors, hemodynamic changes, glycemic control, inflammation, proteinuria and novel mechanisms such as non-coding RNAs and lipotoxicity.

Diabetes is a noncommunicable disease and arguably represents the greatest pandemic in human history. Diabetic kidney disease (DKD) is seen in both type 1 and type 2 diabetes and can be detected in up to 30–50% of diabetic subjects. DKD is a progressive chronic kidney disease (CKD) and is a leading cause of mortality and morbidity in patients with diabetes. Renal fibrosis and inflammation are the major pathological features of DKD. There are a large number of independent and overlapping profibrotic and pro-inflammatory pathways involved in the pathogenesis and progression of DKD. Among these pathways, the transforming growth factor-β (TGF-β) pathway plays a key pathological role by promoting fibrosis. Sirtuin-1 (SIRT1) is a protein deacetylase that has been shown to be renoprotective with an anti-inflammatory effect. It is postulated that a reduction in renal SIRT1 levels could play a key role in the pathogenesis of DKD and that restoration of SIRT1 will attenuate DKD. Cell division autoantigen 1 (CDA1) synergistically enhances the profibrotic effect of TGF-β in DKD by regulating the expression of the TGF-β type I receptor (TβRI). CDA1 has also been found to be an inhibitor of SIRT1 in the DNA damage response. Indeed, targeting CDA1 in experimental DKD not only attenuates diabetes-associated renal fibrosis but also attenuates the expression of key pro-inflammatory genes such as tumor necrosis factor-α (TNF-α) and Monocyte Che moattractant Protein-1 (MCP-1). In conclusion, there is a large body of experimental data to support the view that targeting CDA1 is a superior approach to directly targeting TGF-β in DKD since it is not only safe but also efficacious in retarding both fibrosis and inflammation.

One of the major complications of diabetes mellitus is diabetic nephropathy (DN), the pathogenesis of which is primarily driven by oxidative stress. As a major regulator of antioxidant responses, the transcription factor nuclear factor erythroid 2-related factor 2 (NRF2) has recently attracted much interest. NRF2 is a primary defense mechanism against the cytotoxic effects of oxidative stress, involving heterogeneous detoxification, the production of antioxidants and anti-inflammatory molecules, DNA repair, nuclear chaperones, and proteasome systems. A myriad of studies in pre-clinical models of DN have consistently demonstrated a beneficial effect of NRF2 activation, suggesting that NRF2 is likely a promising target for treating DN. This has been further supported by findings from clinical trials of bardoxolone methyl, an activator of NRF2, despite the unexpected adverse cardiovascular effects. This review summarizes the support for therapeutic targeting of NRF2 in DN and emphasizes the need for the optimization of NRF2-based treatment with the minimization of potential adverse effects.

Membranous nephropathy (MN) is the most common glomerular disease in adults and is constantly associated with the occurrence of nephrotic syndrome. While diabetic kidney disease (DKD) and diabetic nephropathy (DN), which often occur in diabetic patients, are considered as the major causes of end-stage kidney disease. Actually, MN often occurs in patients with diabetes mellitus (DM), but to obtain a clear differential diagnosis without a renal biopsy has become difficult. Here we report the case of a female diabetic patient who developed both MN and DN simultaneously.

Deafness, diabetes and proteinuria are typically understood to be an uncommon combination. Here, we reported a 26-year-old woman with a history of persistent deafness, diabetes mellitus, and proteinuria. The diagnosis mainly depends on clinical symptoms, but the cause of the disease should be examined. The histological finding in renal biopsy showed secondary focal segmental glomerular sclerosis (FSGS), but not classic diabetic nephropathy. Further pathogeny was found. Subsequently, a 3243A>G mutation in the mitochondrial DNA was found. Thus, the diagnosis of maternally inherited deafness and diabetes (MIDD) was considered. Ineffective and unnecessary immunosuppression can be avoided through timely diagnosis. Long-term treatment of CoQ10 can be useful in MIDD patients.