Lipid Peroxidation as a Possible Factor Affecting Bone Resorption in Obese Subjects-Preliminary Research.

Oxidative stress, which promotes bone catabolism, also affects the quality of bone tissue. We aimed to assess the impact of metabolic disorders and oxidant-antioxidant imbalance associated with primary obesity on bone resorption and formation processes. Anthropometric parameters, metabolic variables, oxidative stress indicators (malondialdehyde, vitamins A and E, uric acid, superoxide dismutase, catalase, glutathione peroxidase, type 1 paraoxonase, iron-reducing plasma antioxidant power) and markers of bone turnover (type I procollagen N-terminal propeptide and the type I collagen C-terminal cross-linked telopeptide; P1NP and CTX) were assessed in 108 Polish participants. Under the influence of oxidative stress, both enzymatic and non-enzymatic defense mechanisms were stimulated in obese subjects, especially in women, who had increased lipid peroxidation and activity of catalase (particularly in first-degree obesity) and decreased vitamin E concentration. The process of lipid peroxidation, as well as the weakening of the bone formation, was strongly manifested in women at a BMI range of 35.0-39.9 kg/m2 but not at BMI > 40.0 kg/m2, but it had a comprehensive negative impact on bone turnover in obese men. Obesity and its degree of advancement significantly affected the decrease in the concentration of the marker of bone formation-P1NP-only in the plasma of women. Excessive body weight had no effect on the value of the bone resorption marker in plasma, regardless of gender. Our results confirm the existence of the "obesity paradox" in the aspect of bone tissue metabolism and suggest that a specific body weight threshold changed the molecular response of the tissue.

Serum Arylsulfatase and Acid Phosphatase Activity in Patients with Metabolic Syndrome as a Result of Oxidative Damage to Lysosomes.

BACKGROUND: Metabolic and clinical disorders forming the complex of interrelated abnormalities is known as metabolic syndrome (METs). OBJECTIVE: Our goal was to assess the dependence of serum arylsulfatase (AS) and acid phosphatase (ACP) activities on anthropometric and biochemical parameters in patients with METs. METHODS: In 142 patients with METs (IDF criteria), consisting of different components in different sequences (hypertension, diabetes, lipid disorders), and in 65 healthy participants, basic biochemical parameters were determined in laboratory tests. The activity of serum hydrolases was determined using Bessey's (ACP) and Roy's (AS) methods. RESULTS: The AS activity is correlated with waist-to-hip ratio (WHR) (more strongly in women and in most advanced METs), BMI (in men), and triglycerides (TG) (in women, participants with I degree obesity, and those with three METs components). The ACP activity correlated with the WHR of patients with II degree obesity, TG in those with III degree of obesity, and total cholesterol (TC) in those with four METs components. CONCLUSION: Increased AS activity in patients with METs compared to lower AS activity in the control group may be due to decreased lysosomal function and related to the amount of adipose tissue. Low activity of ACP in the blood serum of patients with METs compared to high activity of ACP in the control group may indicate exhaustion of the lysosomal apparatus and loss of hydrolytic activity. The increase in TG and TC in groups with an increasing number of METs-defining components may be due to the abnormal lysosomal degradation of these compounds.

Evaluation of Selected Parameters of Lipid Peroxidation and Paraoxonase Activity in Blood of Patients with Joint Osteoarthritis.

BACKGROUND: Oxidative stress constitutes an important risk factor for tissue/cell damage and is involved in the occurrence and progression of Osteoarthritis (OA). OBJECTIVE: The aim of this study was to evaluate the concentration of Malondialdehyde (MDA) in Synovial Fluid (SF) and blood as well as the activity of serum and SF paraoxonase (PON1) of patients with OA. Our study aimed to assess local and systemic responses to oxidative stress. METHODS: The study included 43 subjects with OA qualified to total joint replacement. The control group consisted of 58 subjects with no musculoskeletal disorders. The malondialdehyde level were measured in venous blood plasma, erythrocytes (MDAe) and Synovial Fluid (SF) while PON1 activities were estimated in serum and SF. RESULTS: No differences in MDA concentrations in erythrocytes and blood plasma between healthy subjects and OA patients were observed. The significant higher level of MDA in SF compared with blood serum was seen in both genders (in woman about 46.2%, in men - 75.0%) and in both assessed joints (in hip about 53.8%, in knee - 115.9%). Total protein concentration and PON1 activity in serum were significantly higher in OA patients (about 14.6% and 87.9% respectively). The systemic response to osteoarthritis (serum PON1 activity) was higher about 33.6% in men than women and not dependent on affected joint. CONCLUSION: The changes observed in osteoarthritic SF show that the process of antioxidant enzymatic defence is intensified locally, not systemically. The lipid hydroperoxides elimination may lead to restore joints homeostasis.

The concentration of thiobarbituric acid reactive substances (TBARS) and paraoxonase activity in blood of patients with osteoarthrosis after endoprosthesis implantation.

BACKGROUND: The aim of this study was to evaluate the concentration of malondialdehyde (MDA) in erythrocytes and in blood plasma and the activity of blood paraoxonase (PON1) of patients with osteoarthrosis (OA) submitted to endoprosthesis implantation for evaluating oxidative stress. MATERIAL/METHODS: Study was conducted on 55 patients with OA and on 54 total movement-efficient volunteers. The material for the study was venous blood plasma, serum and erythrocytes. RESULTS: Increased concentration of MDAe before surgery was observed in the group of men and in patients with a degenerative process affecting hip joints. After an implantation of endoprosthesis, MDAe decreased to the level observed in the control groups. In the study group MDA concentration in plasma was slightly lower before surgery, and after an operation it reached the value of the parameter of the reference groups. Regardless of sex or age, paraoxonase activity was almost twice as high in almost all subgroups as in the reference group. A positive correlation between PON 1 activity and MDAe concentration was demonstrated both before and after surgery in the group of men. CONCLUSIONS: The increase of PON1 activity in patients' serum in relation to the control groups indicates a probable pathogenic role of the increased formation of reactive oxygen species in the course of OA and may suggest acute inflammation of the synovial joint. The high level of PON 1 activity after endoprosthesis implantation indicates that surgical treatment may additionally stimulate ROS generation. MDAe concentration indicate more intensive process of lipid peroxidation in the elderly.

Oxidative equilibrium in the prophylaxis of degenerative joint changes: an analysis of pre- and postoperative activity of antioxidant enzymes in patients with hip and knee osteoarthritis.

BACKGROUND: Osteoarthritis is often accompanied by disturbance of oxidative equilibrium. The aim of the study was to analyze antioxidant defense system function in patients with hip and knee osteoarthritis by assessing superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activity in erythrocytes. MATERIAL/METHODS: The study included 26 women and 18 men who underwent hip or knee arthroplasty. The pre- and postoperative activities of the antioxidant enzymes were evaluated. SOD activity was determined using the Misra/Fridovich method, CAT by the Beer/Seizer method, and the activity of GPx by the Paglia/Valentine method. The results were compared with those of a healthy control group. RESULTS: SOD activity of the patients was insignificantly lower than in the control group. However, after arthroplasty it increased in subgroups: in males by 13% (p<0.04), in females by 7% (p<0.05), in the group <69 years of age by ca. 14%) (p<0.01), and in the group with idiopathic OA by 12% (p<0.005). The activities of CAT and GPx in all the patient groups were significantly higher than in the controls. It increased even more on the 10th day after arthroplasty with the exception of the patients with rheumatoid osteoarthritis, in whom a decrease by 65.5% (p<0.008) were found, and in the patients > or =69 years old by 9.3% (NS). CONCLUSIONS: Knowledge of antioxidant enzyme activity might offer new targets for future therapeutic methods for the treatment of degenerative joint disease.

Cell cycle, melanin contents and apoptosis processes in B16 and Cloudman S91 mouse melanoma cells after exposure to cytostatic drugs.

Free radicals are generated in cells during many metabolic processes and eliminated from an organism by complex enzymatic and nonenzymatic systems. Many chemical compounds--among others melanin, reveal antioxidative properties. In this work the influence of some cytostatic drugs (at EC50) on melanin content and on the apoptotic processes in mouse melanoma B16 and Cloudman S91 cells in vitro were investigated. The cells were incubated with adriblastin, actinomycin D, cytosine arabinoside, cisplatin, dacarbazine and vincristine. The number of viable mouse melanoma B16 and Cloudman S91 cells was estimated by flow cytometry analysis and melanin content in colorimetric assays. Apoptotic cells were detected using the annexin V-FITC test. The majority of tested cytostatic drugs caused an increase of melanin content in the cells of both melanoma lines, except cisplatin and dacarbazine in the case of B16 cells and dacarbazine in the case of Cloudman S91. Adriblastin, actinomycin D and vincristine evoked apoptosis in the both tested cell lines. Slight increase of melanin content in melanoma cells can be a cell answer to free radicals generation by some cytostatic drugs like adriblastin, actinomycin D and vincristine.

[Tissue engineering yesterday and today. Part II]. / Hodowla komórek, inzynieria tkankowa i medycyna regeneracyjna. Czesc II.

Science and technology is always an important component of human culture. Science directs technological innovation and technology accelerates the progress of science. Increasing number of achievements in tissue engineering domain make possible ex vivo maintaining not only the isolated cells, but also tissues and organs. Tissue engineering powerfully expanding from over hundred years, contribute to the development of genetics, transplantology, oncological diagnostics, pharmacology, toxicology and many other medical sciences. Presented paper summarizes the scientists' accomplishments in the field of tissue engineering which were noted in the second half of twentieth century.

[Cell culture, tissue engineering and regenerative medicine. Part I]. / Hodowla komórek, inzynieria tkankowa i medycyna regeneracyjna. Czesct I.

Tissue engineering is an interdisciplinary field that applies the principles and methods of engineering and the cell culture toward the development of biomaterials that restore, maintain or improve tissue function. The amalgamation of engineering and medicine has interested many scientists for at last two hundred years. What was the goal of cell culture? First, for progress in life sciences achievement and subsequent for virology and toxicology development. In vitro studies are done because of many problems with carrying out animal experiments. In this work the authors present the attempts of physicians, anatomopathologists, embryologists and biologists which contributed to fast development of new area in medicine--tissue engineering.

B16 and cloudman S91 mouse melanoma cells susceptibility to apoptosis after dacarbazine treatment.

Considering the necessity of an individual choice of cytostatic drugs for patients with cancer disease and tumor cells' resistance to these compounds, their ability to induction of apoptosis should be investigated. The aim of this study was to determine the influence of dacarbazine (DTIC) on morphology and kinetics of proliferation of B16 and Cloudman S91 cells. It is important to determine the kind of death induced by the DTIC and the effect of a specific concentration. The evaluation of apoptosis and necrosis in these two mouse melanoma cell lines in vitro was performed. Induction of apoptosis was estimated in annexin V binding assay by flow cytometry. DNA content and cell cycle phases were determined by propidium iodide staining. DTIC induced morphological changes typical for apoptosis and necrosis in both cell lines. DTIC caused cell cycle arrest in S and G2/M phase of both cell lines which showed hypertetraploidy. The highest induction of apoptosis was observed in DTIC concentration of 200 microg/mL for B16 cells (11%) and 100 microg/mL for apoptosis Cloudman S91 cells (22.2%). Higher doses of DTIC caused intensification of necrotic process. The B16 melanoma cells are more sensitive to DTIC than the Cloudman S91 cells, however more intensive apoptotic process was detected in Cloudman S91 cells already at lower concentration of DTIC.