ИСТИНА

Despite more than a century of carnosine research, the list of its biological effects still expands. Its high antioxidant activity is well established, opening the perspectives for its use as a neuroprotector in various pathologies. At the same time, the idea about its regulatory action in the cell, quoting A.A.Boldyrev, "new concept for the function of an old molecule", is expanding. Using in vivo and in vitro experiments, we have solved the crucial question of exogenous carnosine penetration into brain cells. Single intraperitoneal injection of carnosine to mice (1 g/kg) has led to its significant increase in the brain. In the primary cerebellum culture in vitro carnosine showed the ability to penetrate into neurons with the help of the PEPT2 transporter and prevent the growth of ROS under conditions of oxidative stress and excitotoxicity. Two models of focal cerebral ischemia in rats (irreversible and reperfusion) confirmed the direct neuroprotective effect of carnosine - prevention of oxidative damage and apoptosis in the ischemic penumbra in both preventive (150 mg/kg) and postischemic administration (50 mg/kg). Additional investigation of carnosine influence on learning and memory under both stressful and normal conditions was held in animals. The potentiating effect of carnosine on learning is mediated by a consistent increase in the antioxidant system activity and content of monoamine neurotransmitters in the brain. The data on the general mechanisms of carnosine neuroprotective and modulatory effects, reviewed as a functional continuum, allow us to substantiate the idea of its adaptogenic role in the central nervous system.