Uric acid is commonly known for its bad reputation. However, it has been shown that uric acid may be actively involved in neurotoxicity and/or neuroprotection. These effects could be caused by oxidative stress or inflammatory processes localized in the central nervous system, but also by other somatic diseases or systemic conditions. Our interest was to summarize and link the current data on the possible role of uric acid in cognitive functioning. We also focused on the two putative molecular mechanisms related to the pathological effects of uric acid—oxidative stress and inflammatory processes. The hippocampus is a prominent anatomic localization included in expressing uric acid's potential impact on cognitive functioning. In neurodegenerative and mental disorders, uric acid could be involved in a variety of ways in etiopathogenesis and clinical presentation. Hyperuricemia is non-specifically observed more frequently in the general population and after various somatic illnesses. There is increasing evidence to support the hypothesis that hyperuricemia may be beneficial for cognitive functioning because of its antioxidant effects but may also be a potential risk factor for cognitive dysfunction, in part because of increased inflammatory activity. In this context, gender specificities must also be considered.

Renewing interest in immune aspects of schizophrenia and new findings about the brain-fat axis encourage us to discuss the possible role of interleukin-6 (IL-6) in schizophrenia. Previously, it was suggested that a primary alteration of the innate immune system may be relevant in schizophrenia. Functional dichotomy of IL-6 suggests that this chemical messenger may be responsible for regulating the balance between pro- and anti-inflammatory responses, with tissue-specific properties at the periphery and in the central nervous system. Specific phase of this chronic and deteriorating disorder must be considered, which can involve IL-6 in acute or possible chronic inflammation and/or autoimmunity. We give an overview of IL-6 role in the onset and progression of this disorder, also considering cognitive impairment and metabolic changes in patients with schizophrenia. Data suggest that decreased serum level of IL-6 following antipsychotic therapy could be predisposing factor for the development of obesity and obesity-related metabolic disorders in schizophrenia. As we reviewed, the IL-6 plays significant role in disease genesis and progression, so the use of specific inhibitors may not only be beneficial for exacerbation and alleviation of positive symptoms, but may attenuate cognitive impairment in patients with schizophrenia.

The purpose of this study was to examine functional capacity of cardio-respiratory system in patients with schizophrenia, and to evaluate the effects of 12 weeks prescribed physical activity on aerobic capacity and symptoms of schizophrenia. Study involved 80 hospitalized patients with any of the subtypes of schizophrenia (42 men, 38 women). They were divided into two groups: exercise and control group, both with 40 patients. Maximal aerobic capacity (VO2 max) as an indicator of cardiovascular fitness has been obtained by cardiopulmonary stress test on a treadmill. Twelve weeks program of prescribed physical activity (45 minutes, four times per week) was made for every patient individually. Patients in exercise group practiced in training zone between 65 and 75% of their maximum heart rate (HR). Target HR was controlled by Polar F4 monitors. Symptoms of schizophrenia were measured by using Positive and Negative Symptoms Scale (PANSS). Before the exercise program was introduced, measured VO2 max was significantly lower in patients with schizophrenia, than the expected average value in matched healthy subjects (p<0.001). After twelve weeks, patients in exercise group showed a significant increase of VO2max (p=0.002), and significantly higher level of VO2max compared to the control group (p=0.000). Significant differences were also observed on PANSS general psychopathology subscale (p=0.007) and on PANSS total score (p=0.001). The pharmacotherapy and exercise had influence on PANSS general psychopathology (p=0.002) and PANSS total score (p=0.001). Individuals with schizophrenia have lower levels of aerobic capacity compared to general population. Prescribed physical activity significantly improves aerobic capacity in people with schizophrenia and it is effective in amelioration of some psychiatric symptoms. Prescribed physical activity could be an effective adjunctive treatment for patients with schizophrenia, not only for prevention and treatment of comorbidities, but also having an impact on symptoms of schizophrenia.