Likhitskyi O. The use of cryopreserved placental tissue for correction of the reparative osteogenesis processes of the lower jaw during an angular fracture with osteoporosis (experimental study)

The study of the effect of cryopreserved xenografts of human placenta on the repairing bone tissue of the mandible on the background of the simulated osteoporosis was performed of the rats. Animals were divided into the following groups: group 1 - control, animals with combined pathology: rats injured in the lower jaw (fracture of the mandible (FM)) on the background of the modified osteoporosis (OP); group 2 - study of the effect of cryopreserved human placenta tissue (CP) on repair of bone tissue in animals having a combined pathology (OP + FM): 24 hours after the manipulation, a subclause of fragments of human placental tissue was performed; group 3 - study of the effect of cryopreserved tissue placenta in combination with calcium citrate preparation in animals with a combined pathology. The stimulating effect of cryopreserved tissue of the placenta on the proliferation and differentiation of cell and tissue components of bone regenerate has been prove. It is substantiated that the cryopreserved tissue of the placenta has the ability to influence the acceleration of formation of osteoid tissue and on the growth of bone beams with the emergence of active mineralization sites. It is shown that bone reparation processes take place in a shorter term, more dynamically, on a qualitatively new level. For the first time, the peculiarities of the course of oxidative and nitrosamine stress at different stages of reparative osteogenesis in rats with an open fracture of the mandible on the background of osteoporosis were determined. It has been shown that the activity of free radical oxidation of lipids and proteins, as well as the production of nitrogen monoxide and superoxide anion-radical (with the participation of NADPH-oxidase) begins to increase already on day 7 after the trauma and reaches the maximum values on 14-21 days of reparative osteogenesis, after which gradually decreasing to normal. Instead, the activity of neutralizing superoxide anion with the participation of superoxide dismutase begins to decrease already on 7 day after the fracture, and on 14-21 days, it becomes minimal. For the first time an important role of oxidative degradation of proteins, nitrosative stress and imbalance in the system of cytokines of TNF-α and TGF-β1 in metabolic collagen transformations in the open fracture of the mandible on the background of osteoporosis was determined. For the first time, it has been shown that the activity of osteodestruction and osteosynthesis in open fracture of the mandible on the background of osteoporosis depends on the cytokine profile of the blood serum (TNF-α, IL-8, VEGF and TGF-β1), production of superoxide anion radical with the participation of NADPH oxidase, the activity of free radical oxidation of proteins and the degree of nitrosative stress.For the first time, it has been shown that the combined use of cryopreserved tissue of the placenta and calcium citrate preparation in rats with an open fracture of the mandible on an osteoporosis background corrects a number of metabolic and immunological processes, namely, reduces collagen degradation by 7-21 days; increases collagen formation activity by 14-30 days; increases the index of mineralization of bone tissue by 7-30 days; restores the balance in the system of anti-oxidant enzymes, which is associated with the slowdown of the activity of free radical oxidation of lipids and proteins, nitrosative stress by 7-21 days; reduces the level of proinflammatory cytokines of TNF-α, IL-8 for 7-21 days; increases the content of the angiogenic factor VEGF and growth factor TGF-β1 at 14-30 days after injury.