CC BY
4The 30th International Conference on Advanced Laser Technologies
B-O-10
ALT'23
Biomedical metabolic imaging revealed new criteria for reducing the
regenerative potential of the liver
S.A. Rodimova1, V.V. Elagin1, A.M. Mozherov1, I.D. Shchechkin12, D.P. Krylov12, D.S. Kozlov12, M.M. Karabut1, A.I. Gavrina12, N.V. Bobrov13, V.E. Zagainov14, E.V. Zagaynova1, D.S. Kuz-
netsova12
1 - Privolzhsky research medical university, 603005, Nizhny Novgorod, Minin and Pozharsky sq. 10/1 2 - Lobachevsky Nizhny Novgorod National Research State University, 603022, Nizhny Novgorod, Gagarina 23 3 - The Volga District Medical Centre of Federal Medical and Biological Agency, 603000, Nizhny Novgorod, Ilinskaya
st. 14
4 - Nizhny Novgorod Regional Clinical Oncologic Dispensary, Nizhny Novgorod, Delovaya St. 11/1
e-mail: daria. s. kuznetsova@gmail.com
Surgical liver resection remains the most effective treatment of liver tumors [1]. However, in the presence of hepatic pathologies, the regenerative potential of the liver is significantly reduced [2]. Standard clinical methods do not allow predicting the function of the liver remnant. Modern label-free methods of multiphoton microscopy with fluorescence lifetime imaging microscopy (FLIM) and second harmonic generation (SHG) allow to determine the criteria for reducing the regenerative potential of the liver with concomitant hepatic pathology.
A series of experiments were carried out on Wistar rats. Toxic liver fibrosis was induced by CCl4 injections and steatosis was induced by 60% high-fat diet. At different stages of the pathology, we induced liver regeneration by 70% hepatectomy. Using multiphoton microscopy, we analysed the structure of the liver tissue on 3rd and 7th day after hepatectomy, and also determined the intensity of NAD(P)H autofluorescence in the zones of low and high signal. Using FLIM, we determined the fluorescence lifetime contributions of the free and bound forms of NADH and NADPH. Morphological analysis and a standard biochemical blood test were performed as controls.
As a result, we revealed the features of the structural and functional state at different stages of liver regeneration with steatosis and fibrosis. In case of steatosis, we identified zones with a reduced NADH autofluorescence intensity, corresponding to lipid infiltration or fibrosis. The area of zones with a reduced NAD(P)H autofluorescence intensity increased with the development of steatosis. We also showed a decrease in the contributions of the bound form of NADH and NADPH already in the early stages of steatosis. During regeneration with the presence of steatosis, there was no sharp increase in the contributions of the bound form of NADH and NADPH on the 3rd day after hepatectomy, due to mitochondrial dysfunction of hepatocytes. In case of fibrosis, we also identified zones with a reduced signal of NADH autofluorescence intensity, which corresponded to fibrosis. The area of zones with a reduced NAD(P)H autofluorescence intensity increased with the development of fibrosis. There was sharp a decrease in the contributions of the bound form of NADH and NADPH in the early stages of pathology, followed by an increase in these parameters in the later stages. Such changes are associated with mitochondrial dysfunction in the early stages and the progression of compensatory processes in the later stages of pathology.
The work was supported by the Grant from the Russian Science Foundation №19-15-00263.
[1] E. Ramos., J. Torras., L. Lladô. et al., The influence of steatosis on the short-and long-term results of resection of liver metastases from colorectal carcinoma, Hpb, 18(4), 389-396 (2016).
[2] V.E. De Meijer, B.T. Kalish, M., Puder, J.N.M. IJzermans, Systematic review and meta-analysis of steatosis as a risk factor in major hepatic resection, Journal of British Surgery, 97(9), 1331-1339, (2010).
