Stress and immunosuppression: opportunities for pharmacorrection

Introduction. Factory-farmed animals are constantly exposed to a variety of stress factors. Medical drugs, pesticide residues in feed, and other toxic agents entering the animal body play a special role in it. The combined effect of these factors is the most dangerous, since it is often accompanied by the immune system dysfunction. The purpose of the study is to reveal the mechanisms of immunosuppression under stress and the opportunities for pharmacological immunocorrection. Materials and methods. Data search was carried out in domestic and foreign databases ‒ eLibrary.ru, Scopus, Web of Science, and PubMed. The integrative approach was used to assess the mechanisms of immunosuppression and the corrective role of vitamins, glutathione, melatonin, and trace elements. Research results and discussion. The immunotoxic effects of chemical stressors are different, but in most cases, they trigger oxidative stress. Hyperproduction of free radicals contributes to the intensification of lipid and protein peroxidation processes, which is accompanied by a violation of the effector functions of macrophages/neutrophils and a suppression of antibody production. Alpha-tocopherol is the first line of anti-lipid peroxidation defense. It plays an important role in selenium metabolism, which is part of glutathione peroxidase. Carotenoids are involved in the division of immunocompetent cells and the synthesis of immunoglobulins. Ascorbic acid is the synergist of beta-carotene. Melatonin, as an antioxidant, binds to the most toxic hydroxyl radicals, as well as peroxynitrite, singlet oxygen, and peroxyl radical. Trace elements (zinc, copper, and selenium) regulate cell differentiation, proliferation, and apoptosis. They also participate in the work of innate and adaptive immunity. Conclusion. Immunosuppression developing under stress conditions increases the animal’s susceptibility to infectious diseases and causes severe infection. The presented data on the role of fat- and water-soluble vitamins, melatonin, and trace elements in the regulation of the immune response confirm the feasibility of their application in animal husbandry as means of pharmacorrection in cases of immunosuppression.