Aim. To study the state of the antioxidant system in mitochondria of skin cells during B16/F10 melanoma growth in mice with chronic neurogenic pain. Materials and methods. The study included female С57ВL/6 mice ( n = 28). Experimental groups included an intact group, a control group – chronic neurogenic pain model, a comparison group – standard subcutaneous transplantation of В16/F10 melanoma, and a main group – transplantation of В16/F10 melanoma 3 weeks after creation of a model of chronic neurogenic pain. Animals were decapitated on day 14 of the В16/F10 melanoma growth, the skin was excised and mitochondria were isolated . Standard ELISA test systems were used to determine the levels of reduced glutathione (GSH) and oxidized glutathione (GSSG) (Bio Source, USA) ; glutathione peroxidase-4 ( GPx 4) (Clod-Clon Corporation, CNDR); glutathione reductase (GR) (Cusabio, CNDR); glutathione S-transferase (G-S-T) (Ivvundiagnostik, Germany); glutathione peroxidase-1 (GPx 1), and superoxide dismutase-2 (SOD-2) (Ab Frontier, South Korea). Results . Mitochondria of skin cells in controls showed an increase in the levels of GSH by 1.3 times, GPx 1 – by 2.9 times, GPx 4 – by 1.9 times, GR – by 2.8 times, and SOD-2 – by 2.4 times, compared to intact animals. Changes in the comparison group were opposite: GPx 1 decreased by 1.9 times, GPx 4 – by 3.7 times, GR – by 3.9 times, SOD-2 – by 3.8 times, and GSSG rose by 1.36 times compared to intact animals. The growth of melanoma with chronic neurogenic pain caused an increase in the levels of GSH by 1.5 times, GPx 1 – by 3.6 times, G-S-T – by 1.28 times, GPx 4 – by 1.6 times, and SOD-2 – by 1.8 times, compared to intact animals. Conclusions . The growth of В16/F10 melanoma together with chronic neurogenic pain restructures the antioxidant system of skin mitochondria towards generation of reductive stress under the influence of chronic pain, which can affect the growth and development of experimental melanoma.

Purpose of the study . Studying the dynamics of growth factors (GF) in urokinase (uPA)-deficient mice with chronic neurogenic pain (CNP) and B16/F10 melanoma. Materials and methods . Levels of VEGFA, VEGFC, sVEGFRl, sVEGFR3, IGF1, IGF2, TGFp1 and FGF21 were determined by ELISA in tumors, perifocal tissues (PT) and the skin of male and female С 57 BL/6 mice (with a normal genome, n = 75) and C57BL/6-Plautm1.1BugThisPlauGFDhu/GFDhu mice (uPA-deficient animals, n = 46) at 3nd week of the carcinogenesis and CNP. Results . The skin of intact uPA-deficient mice demonstrated higher GF levels than in C57BL/6 mice, but VEGF- А and TGF-p1 in males (unlike females) were 4.4 and 5 times lower than in C57BL/6 males. This changes were generally similar in the skin of C57BL/6 mice with CNP. uPA-deficient females showed elevated GF in PT, especially VEGF- А and IGF1 — by 21.5 and 8.1 times, respectively in simultaneously CNP and growth of the melanoma. uPA gene-knockout males had similar changes in GF, although less marked. The levels of all studied GF in tumor tissue were lower than levels in PT in both males and females, except for VEGFA in males — 5.6 times higher in tumor tissue. Changes in PT of C57BL/6 mice were similar: maximally increased levels of all GF, especially VEGF, IGF and TGF-p1 — in females on average by 6.2, 15.9 and 5.5 times, respectively, in males by 9.4, 5.9 and 6.7 times, respectively, compared to the skin levels. While the absolute values of GF concentrations and the intensity of changes were higher than in uPA-deficient mice. Conclusion . In general, skin levels of GF in intact uPA-deficient mice were similar to the levels in mice without uPA-deficient with CNP. The GF dynamics was analogous in mice of both lines at simultaneously CNP and growth of the melanoma, but the intensity of changes in mice without uPA-deficient was significantly higher implying a synergic effect of CNP and paracrine influence of melanoma on the GF levels.