Autophagy Mechanisms in Diabetic Kidney Disease

Autophagy is a conserved intracellular degradation pathway that maintains renal cellular homeostasis by removing damaged proteins and organelles via lysosomal clearance. In diabetic kidney disease, chronic hyperglycaemia, advanced glycation end products and dyslipidaemia disrupt autophagic flux in critical renal cell types, notably podocytes and proximal tubular epithelial cells. Impairment of autophagy exacerbates oxidative stress, mitochondrial dysfunction and inflammation, leading to podocyte foot process effacement, barrier disruption and tubulointerstitial fibrosis. Key regulatory nodes include the mammalian target of rapamycin complex 1, which senses nutrient excess and suppresses autophagy, and AMP-activated protein kinase, which is activated by energy depletion to promote autophagy. Transcription factor EB, which governs lysosomal biogenesis and autophagic gene expression, is inhibited under diabetic conditions. Crosstalk between autophagy and apoptosis further determines cell fate, with insufficient autophagy tipping the balance towards cell death. Restoring autophagic competence has emerged as a promising strategy to preserve renal function, with pharmacological modulation of signalling pathways and nutrient sensors offering concrete therapeutic potential.

Research from Nature Portfolio

A seminal investigation revealed that exposure of cultured podocytes to elevated levels of free fatty acids triggers reactive oxygen species–dependent activation of autophagy, which acts protectively against lipid-induced apoptosis. Inhibition of autophagy in this model intensified oxidative injury and mitochondrial depolarisation, whereas promotion of autophagy by pharmacological agents ameliorated podocyte loss. These findings established a direct link between lipid dysregulation, oxidative stress and autophagic defence mechanisms in the context of diabetic glomerular injury.

Autophagy Mechanisms in Diabetic Kidney Disease publication trend

The graph below shows the total number of articles in autophagy mechanisms in diabetic kidney disease across all publications each year (not limited to Nature Index journals).

Technical terms

Autophagy: A lysosome-mediated degradation process that recycles cellular components to maintain homeostasis and energy balance.

Podocyte: A specialised epithelial cell in the glomerulus that forms part of the filtration barrier and is highly reliant on autophagy for survival.

Mitophagy: A selective form of autophagy whereby damaged or superfluous mitochondria are targeted for degradation.

mTORC1: The mammalian target of rapamycin complex 1, a nutrient sensor that inhibits autophagy when activated by growth factors or energy abundance.

AMPK: AMP-activated protein kinase, an energy sensor that activates autophagy under conditions of cellular energy deficit.

Reactive oxygen species (ROS): Chemically reactive molecules derived from oxygen that can damage cellular structures but also act as signalling mediators for autophagy.

References

1. ADP-Ribosylation Factor-Interacting Protein 2 Acts as a Novel Regulator of Mitophagy and Autophagy in Podocytes in Diabetic Nephropathy. Antioxidants (2024).
2. Activation of acetyl-CoA synthetase 2 mediates kidney injury in diabetic nephropathy. JCI Insight (2023).
3. Autophagy Protects against Palmitic Acid-Induced Apoptosis in Podocytes in vitro. Scientific Reports (2017).
4. Autophagy-Lysosome Pathway in Renal Tubular Epithelial Cells Is Disrupted by Advanced Glycation End Products in Diabetic Nephropathy*. Journal of Biological Chemistry (2015).
5. Advanced glycation end‐products suppress autophagic flux in podocytes by activating mammalian target of rapamycin and inhibiting nuclear translocation of transcription factor EB. The Journal of Pathology (2018).