1. Department of Physiology and Pathophysiology, Medical University of Varna, 9002 Varna, Bulgaria
2. Department of General Medicine, Medical University of Varna, 9002 Varna, Bulgaria
3. Department of Conservative Dental Treatment and Oral Pathology, Medical University of Varna, 9002 Varna, Bulgaria
4. Department of Neurology and Neuroscience, Medical University of Varna, 9002 Varna, Bulgaria
5. Department of Biochemistry, Molecular Medicine and Nutrigenomics, Medical University of Varna, 9002 Varna, Bulgaria