[Effect of melatonin on activity of superoxide dismutase (CuZn-SOD) in erythrocytes of patients during short- and long-term hypokinesis]. / Wplyw melatoniny na aktywnosc dysmutazy ponadtlenkowej (CuZn-SOD) w krwinkach czerwonych chorych w okresie hipokinezji krótko- i dlugoterminowej.

INTRODUCTION: Short- or long-lasting hypokinesis is to a large degree the consequence of negative habits of human beings towards a comfortable and more sedentary lifestyle. The period of decreased physical activity can cause disturbance in the balance between systemic processes of the oxidation and reduction, which leads to an increase in reactive oxygen species (ROS) and oxidative stress generation. The aim of the study was to determine the effect of melatonin administration on the cellular superoxide dismutase (CuZn-SOD) activity in red blood cells of patients with short- and long-term hypokinesis as compared to the group of subjects with normal physical activity. MATERIAL AND METHODS: The study included 33 subjects with immobilization. The study group was divided into two subgroups (depending on hypokinesis duration): group A: 15 subjects classified for total hip alloplasty (a short-lasting decrease in physical activity); group B: 18 subjects suffering from multiple sclerosis or the stroke of brain (the long-term hypokinesis). The control group (group C) comprised 17 subjects with normal physical activity. Melatonin was applied at a dose of 5 mg daily, one hour before sleep. The CuZn-SOD activity in red blood cells was determined, according to the Misra and Fridovich method, in two periods: 1) on the first day, 2) on the 10th day (group A), and 30 days (group B) after melatonin administration. RESULTS: A slight increase in CuZn-SOD activity (+3.1%) was observed in group A 10 days after alloplasty and melatonin administration as compared to group B, where a considerable rise in the enzyme activity (+23.3%) was found 30 days after rehabilitation and melatonin supplementation. The average CuZn-SOD activity in both investigative groups was lower than that in the controls (group C). CONCLUSIONS: It was estimated that the short- and long-lasting hypokinesis leads to an increase in ROS generation, what is confirmed by the increase in CuZn-SOD activity. The results of the study on superoxide dismutase activity indicate that oral administration of melatonin for the period of 30 days has a more favorable influence on antioxidative processes than 10-day's melatonin intake.

DNA damage and repair of head and neck cancer cells after radio- and chemotherapy.

DNA repair is critical for successful chemo- and radiotherapy of human tumours, because their genotoxic sensitivity may vary in different types of cancer cells. In this study we have compared DNA damage and the efficiency of its repair after genotoxic treatment with hydrogen peroxide, cisplatin and gamma-radiation of head and neck squamous cell carcinoma (HNSCC). Lymphocytes and tissue cells from biopsies of 37 cancer patients and 35 healthy donors as well as the HTB-43 larynx cancer cell line were employed. The cell sensitivity to genotoxic treatment was estimated by the MTT survival assay. The extent of DNA damage and efficiency of its repair was examined by the alkaline comet assay. Among the examined treatments, we found that HNSCC cells were the most sensitive to gamma-radiation and displayed impaired DNA repair. In particular, DNA damage was repaired less effectively in cells from HNSCC metastasis than healthy controls. In conclusion, our results suggest that the different genotoxic sensitivity of HNSCC cells may depend on their DNA repair capacity what in turn may be connected with the effectiveness of head and neck cancer therapy.

[The influence of degenerative changes on the production of free radicals and the lipid peroxidation at the patients after alloplasty of the hip joint]. / Wplyw zmian zwyrodnieniowych na generacje wolnych rodników tlenowych i peroksydacje lipidów u chorych po przebytej alloplastyce stawu biodrowego.

UNLABELLED: Since now researches claimed that rheumatoid arthritis was not characterized with an inflammatory process due to the lack of vessel in the cartilaginous tissue. Nevertheless, an inflammation of synovial membrane and a reduction of activity of articulation co-exist with rheumatoid arthritis. Recent results have proved that the above disease is connected with an oxidative stress. AIM OF THE STUDY: The aim of this investigation was to estimate changes of nitric oxide (NO) in plasma and malondialdehyd (MDA) concentration in red blood cells of patients suffering from an alloplastic of the hip joint. We also measured how physical activity in a reduced motor activity influences the NO and MDA concentration. MATERIAL AND METHODS: Malonyl dialdehyde (MDA) concentration in RBCs was assayed with Placer method, nitrogen concentration in blood plasma was determined using the Griess indirect method. Biochemical tests have been performed on a group of 36 patients with osteoarthritis hospitalised at the Traumatic-Orthopaedic Department of the Ministry of Internal Affairs and Administration Hospital in Lodz, Poland. A control group included 21 subjects with normal physical activity. RESULTS: The concentration of nitric oxide in plasma of patients that were operated was lower than in a healthy control group. Ten days after the operation it decreased, but after a month it was higher than before the operation. The concentration of MDA in red blood cells was higher before and after the alloplastic than in the healthy control group. Ten days after operation the concentration of MDA was lower about 15.8% but after 30 days it lowered up to about 26.3% in comparison to the concentration before the operation. CONCLUSIONS: Our results are not the same as those shown by other researches which suggest increased production of nitric oxide. Reduction of the motor activity due to degenerative joint disease and alloplastic causes reduction in lipid peroxidation of red blood cells.

[Activity of superoxide dismutase (CuZn-SOD) in erythrocytes of patients after hips alloplasty]. / Aktywnosc dysmutazy ponadtlenkowej (CuZn-SOD) w krwinkach czerwonych chorych po alloplastyce stawu biodrowego.

UNLABELLED: Hip osteoarthritis leads, among others, to abnormally decreased physical activity (hypokinesia). Adverse effect of physical inactivity can cause inhibition of anabolic processes in favour of enhancement of protein, carbohydrate, and lipid catabolitic reactions, as well as inadequate metabolism of polyunsaturated fatty acids. These alterations can induce an increased lipid peroxide synthesis, overproduction of reactive oxygen species (ROS) and acceleration of lipid peroxidation processes. The aim of the study was to determine superoxide dismutase activity (CuZn-SOD) in red blood cells of patients suffering from hip osteoarthritis prior to and following total alloplasty as compared to healthy subjects, and also to evaluate effect of hypokinesia on oxidative stress. MATERIAL AND METHODS; CuZn-SOD activity in red blood cells was determined according to the Misra and Fridovich method in 36 patients with hip osteoarthritis hospitalized at the Traumatic-Orthopaedic Department of the Ministry of Internal Affairs and Administration Hospital in Lódz. RESULTS: In patients with decreased physical activity in ten days after alloplasty, enzyme activity increased (+24.9%), one month since the operation it decreased, but it higher as compared to result activity of CuZn-SOD prior to surgery (+16.8%). CONCLUSIONS: The results activity of superoxide dysmutase leads to ROS generation and their overgeneration in hip osteoarthritis and in first time of treatment.