Biopolym. Cell. 2023; 39(4):299-310.
Molecular Biomedicine
Angiostatins modulate ACE2 and GFAP levels in injured rat cornea and do not affect viability of retinal pigment epithelial cells
1Bilous V. L., 1Kapustianenko L. G., 1Yusova O. I., 1Korsa V. V., 2Nedzvetsky V. S., 3Ağca C. A., 4Ziablitsev S. V., 1Tykhomyrov A. O.
  1. Palladin Institute of Biochemistry, NAS of Ukraine
    9, Leontovicha str., Kyiv, Ukraine, 01054
  2. Dnipro State Agrarian and Economic University
    25, Serhii Efremov str., Dnipro, Ukraine, 49027
  3. Bingöl University, Selahaddin-i Eyyubi Mah. Üniversite Cad. No: 1
    Bingöl, Turkey, 12000
  4. Bogomolets National Medical University
    34, Beresteiskyy ave., Kyiv, Ukraine, 03057


Aim. To investigate the effects of AS K1-3 and K5 on the protein levels of SARS-CoV-2 receptor, ACE2, and marker of activated satellite glia, GFAP, in the injured rat cornea, and to assess if AS could affect the viability of retinal pigment epithelial (RPE) cells. Methods. AS (K1-3 and K5) were produced by limited proteolysis of plasminogen isolated from human plasma followed by affine chromatography purification. AS (K1-3 0.1 or 1.0 μM, K5 0.1 μM) were applied topically as eye drops in rat model of alkali burn of cornea. The protein level of ACE2 and GFAP was evaluated in corneal tissue lysates by western blot and expressed as arbitrary units (a.u.). The effects of AS on the viability of RPE cells were evaluated by MTT test. Results. The ocular injury caused by alkali burn induced overexpression of both ACE2 (by 7.7 fold vs. control, P<0.001) and GFAP (by 62 folds vs. control, P<0.001). Application of K5 or K1-3 (1.0 μM) reduced the expression level of ACE2 in injured corneas by two-folds (P<0.05 vs. Burn group), whereas K1-3 (0.1 μM) lowered the content of ACE2 by 3.4-folds compared with the Burn group (P<0.05) suggesting that AS can decrease a potential risk of SARS-CoV-2 entry due to the down-regulation of its receptor expression. Interestingly, K5 appeared to be more effective in suppressing the GFAP overexpression (by 10.9-fold vs. Burn group, P<0.01) indicating that AS may act as neuroprotective substances via alleviating excessive response of satellite glia in injured cornea. AS had no cytotoxic effects on retinal pigment endothelium in the range of concentrations 2-100 nM. Conclusions. Collectively, our data may pave the way for a possible application of AS in designing an ophthalmic drug as an effective and safe supplementary with combined protective effects.
Keywords: angiostatins, corneal injury, ACE2, GFAP, RPE cells, , , , ,


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