New experimental model of kidney injury: Photothrombosis-induced kidney ischemia.

Acute kidney injury (AKI) is a frequent pathology with a high mortality rate after even a single AKI episode and a great risk of chronic kidney disease (CKD) development. To get insight into mechanisms of the AKI pathogenesis, there is a need to develop diverse experimental models of the disease. Photothrombosis is a widely used method for inducing ischemia in the brain. In this study, for the first time, we described photothrombosis-induced kidney ischemia as an appropriate model of AKI and obtained comprehensive characteristics of the photothrombotic lesion using micro-computed tomography (micro-CT) and histological techniques. In the ischemic area, we observed destruction of tubules, the loss of brush border and nuclei, connective tissue fibers disorganization, leukocyte infiltration, and hyaline casts formation. In kidney tissue and urine, we revealed increased levels in markers of proliferation and injury. The explicit long-term consequence of photothrombosis-induced kidney ischemia was renal fibrosis. Thus, we establish a new low invasive experimental model of AKI, which provides a reproducible local ischemic injury lesion. We propose our model of photothrombosis-induced kidney ischemia as a useful approach for investigating AKI pathogenesis, studying the mechanisms of kidney regeneration, and development of therapy against AKI and CKD.

Visualization of different anatomical parts of the enucleated human eye using X-ray micro-CT imaging.

Micro-CT visualization allows reconstruction of eye structures with the resolution of light microscopy and estimation of tissue densities. Moreover, this method excludes damaging procedures and allows further histological staining due to the similar steps in the beginning. We have shown the feasibility of the lab-based micro-CT machine usage for visualization of clinically important compartments of human eye such as trabecular outflow pathway, retina, iris and ciliary body after pre-treatment with iodine in ethanol. We also identified the challenges of applying this contrasting technique to lens, cornea, and retina and proposed alternative staining methods for these tissues. Thereby this work provides a starting point for other studies for imaging of human eyes in normal and pathological conditions using lab-based micro-CT systems.