Reactive oxygen species induce apoptosis of synoviocytes in vitro. Alpha-tocopherol provides no protection

Reactive oxygen species (ROS) are released during the inflammation of the synovial membrane associated with cartilage degradation in osteoarthritis. In this work, we exposed synoviocytes to superoxide anions at concentrations that may cause either apoptosis or necrosis. We studied membrane organization, dehydrogenase mitochondrial activity and nuclear morphology and integrity, to determine the nature of the death process initiated by superoxide anions and tried to counteract ROS effects with alpha-tocopherol. We found that oxidative stress caused synoviocytes to undergo a process of cell death of an apoptotic nature rather than necrotic. Mitochondrial injury occurred at an early stage, and the FITC-annexin-V-positive/propidium iodide-positive cells occurred later than the metabolic changes. DNA strand breaks were evident at 8 h and nuclear condensation at 24 h. No LDH activity was detected in culture supernatants. In our experimental conditions, alpha-tocopherol had little effect on stress damage; the antioxidant properties of this molecule did not affect the apoptosis caused by superoxide anions.

Discrimination of osteoarthritic and rheumatoid human synovial cells in culture by nuclear image analysis

Rheumatoid arthritic (RA) and osteoarthritic (OA) synovial cells in culture differ in their metabolic and proliferative behaviour. To assess links between these properties and nuclear changes, we used image analysis to study chromatin texture, together with nuclear morphometry and densitometry of OA and RA cells in primary culture. Chromatin pattern at the third day (D3) was heterogeneous and granular with chromatin clumps whereas at the final stage (D11) of culture a homogeneous and finely granular chromatin texture was observed. This evolution indicates global chromatin decondensation. These characteristics were more marked for RA than for OA nuclei. At each culture time, RA nuclei could be discriminated with high confidence from OA ones from parameters evaluating the organization of the chromatine texture. Nuclear image analysis is thus a useful tool for investigating synovial cell biology.

Markers of oxidative stress in fit, health-conscious elderly people living in the Paris area. The Research Group on Ageing (GERBAP)

Lipid peroxidation index and antioxidant indicators were assessed by biochemical means in 193 healthy elderly volunteers (103 men and 90 women), ages 70-89 y and living freely in the Paris area. Lipid peroxidation index was in the same range as in young adults. Zinc, copper, and selenium levels were satisfactory and similar to those in young adults, though the range of copper values tended to be higher. Copper and selenium levels were higher in elderly women than in men. However, for selenium values this sex-related difference disappeared in elderly volunteers > 75 y. Copper-zinc-superoxide dismutase and glutathione peroxidase activities were similar to those in young adults, with no influence of sex or age. Vitamin E and total carotene, closely related to cholesterol levels, were satisfactory. Our findings show that markers of oxidative stress are not influenced by old age when good health and nutritional status are preserved, as in this selected population.

Methodological considerations on Feulgen-staining applied to cells in primoculture: the model of osteoarthritic synovial cells

Human synovial cells in primoculture are an interesting model for the study of articular joint diseases and anti-rheumatic drugs. Based on results obtained by image cytometry of Feulgen-stained nuclei, we describe the heterogeneity of synovial cell populations and their progression during culture time in primoculture. Using the hydrolysis properties of the Feulgen reaction and their variations dependent on fixatives, we demonstrate the high acid-lability of the condensed chromatin observed in short term cultured nuclei compared to the acid-resistance of decondensed chromatin in long term cultured nuclei; these variations being probably induced by modifications in the molecular supra-organisation of chromatin during the aging of a culture. Finally, due to the cellular heterogeneity of the biological model and its evolution during culture progression, technical compromises are proposed to obtain optimal Feulgen staining, using Böhm-Sprenger fixative and a 1 h hydrolysis by 6 M HCl at 20 degrees C.

Extensive laboratory assessment of nutritional status in fit, health-conscious, elderly people living in the Paris area. Research Group on Aging

OBJECTIVE

Nutritional status-related biological indexes were measured in fit, health-conscious elderly subjects in order to establish reference values for people over 70 years.

SUBJECTS

103 men and 90 women aged 70-89 years living freely in the Paris area volunteered to participate.

METHODS

Nutritional status was assessed by anthropometric and biochemical methods.

RESULTS

Serum protein and amino acid status was similar to that of young adults, with only 5.2% of the elderly subjects showing transthyretin concentrations < 0.20 g/L, as well as decreased essential amino acid levels. Iron status, assessed in terms of serum and erythrocyte ferritin levels, total iron binding capacity and erythrocyte protoporphyrin tended to be satisfactory, but iron depletion was detected in 8.8% of the subjects. Serum ferritin levels were elevated in 19.7% of the subjects. Folate and vitamin B12 status was satisfactory, while hypovitaminosis D was observed in 48.2% of cases.

CONCLUSION

Our findings suggest that, in aging uncomplicated by disease, nutritional status is similar to that in younger adults, although the range of values tended to be wider, with a higher risk of certain nutrient deficiencies.

Semi-automated assay of erythrocyte Cu-Zn superoxide dismutase activity

A semi-automated enzymatic colorimetric method for determining Cu-Zn superoxide dismutase (SOD) in erythrocytes using an FP9 parallel analyzer is described. The method is based on the reaction described by McCord and Fridovich (xanthine/xanthine oxidase, ferricytochrome C), which permits kinetic measurements to be determined colorimetrically for the assay of enzyme activity. The coefficients of variation for within- and between-run analyses were less than 6%. The limit of linearity is 3.5-times the mean value of the normal range while recovery of added SOD ranged from 91 to 120%. The method, which is both reliable and simple, allows rapid, simultaneous measurements of multiple samples.

[Free radicals in clinical biology. Origin, pathogenic effect and defense mechanisms]

Free radicals are chemical species with an unpaired electron on their outer orbit. This review discusses the various endogenous and exogenous sources of free radicals; toxicity of free radicals, especially for DNA and cell membranes; a number of pathophysiologic states related to overproduction of free radicals; the natural protective systems--involving enzymes or scavengers--which prevent free radical-induced cell injury, and therapeutic trials of antioxidants for improving protection against free radicals in a number of conditions.

Influence of sex and age on vitamin A and E status

Vitamins A and E were determined in the serum of 80 free-living healthy elderly subjects and in 80 healthy younger adults. Mean values and normal ranges were established for both groups and the influence of sex and age studied. We found a significantly lower level of vitamin A in the elderly men and women and a higher level of vitamin E in elderly women, relative to their younger counterparts. These differences may be related to life-style and age-associated physiological changes and justify the use of age-corrected standard values.

An epidemiological and clinical study of transaminase levels and hepatitis B antibodies in 1,100 blood donors

In order to provide epidemiological and clinical information on surrogate testing of blood donations, the respective prevalences of serum hepatitis B virus (HBV) markers and elevated transaminase levels were studied in 1,100 blood donors according to their geographic origin and socioeconomic level. The frequency of serum HBV markers varied as a function of HBV endemicity in the country of origin; however, it was inversely correlated (p less than 0.05) to the socioeconomic level of the donors, even in those originating from countries of low HBV endemicity. There was no association between serum HBV markers and the increased transaminase level which was observed in 48 (4.3%) donors. Twenty-five of these accepted further clinical evaluation. A diagnosis appeared probable in 12 of the 25: alcohol in 5; drugs in 6; non-A, non-B hepatitis in 1. Seven of the remaining 13 subjects were more than 25% above ideal body weight. Transaminase activities determined at the time of clinical assessment were normal in 14. In addition, serum HBV DNA was found in 5 of 247 donors, even in the absence of any usual HBV marker and/or hypertransaminasemia. This could account for the few cases of B and B-like posttransfusion hepatitis which are known to still occur despite careful HBsAg screening of blood donors.

The biological effects of retinoids on cell differentiation and proliferation

The retinoids are the natural and synthetic analogues of retinol or vitamin A. These molecules are able to modulate differentiation and proliferation processes in several cell types. The presence of retinoids is essential for inducing or maintaining the differentiation of epithelial cells. On the other hand, when excess retinol is added to the culture medium, the differentiation of some mesenchymal cells is impaired. Retinoids also promote the differentiation of carcinoma cells of various origins: embryonal carcinoma, leukaemic and melanoma cells. While their effect on the proliferation of normal cells appears variable, these molecules inhibit the growth of cells treated with a tumoural promoter, or spontaneously transformed cells, and they prevent tumour promotion. Various mechanisms of action might be involved: retinoids could act at the level of the genome with or without the participation of their binding proteins. They might also influence glycoconjugate biosynthesis and interact, through certain glycosylation reactions, with growth factor receptors. The role of vitamin A and its structural analogues in cell differentiation and growth is of great therapeutic interest.

Fibronectin and retinyl acetate effects on attachment and spreading of normal and rheumatoid human synovial cells

The action of two effectors - fibronectin (FN) and retinyl acetate (RA) - on cell attachment and spreading of human synoviocytes was investigated by adding these two drugs to the cell culture medium. No relationship was observed between the level of the effectors (FN = 20-80 micrograms/well, RA = 0.50-2 micrograms/well) and the biological effects studied. For normal human synoviocytes, fibronectin was less effective on the adhesion than fetal calf serum (FCS) present in the control culture medium; retinyl acetate, a drug acting on glycoprotein synthesis, led to similar effects to those observed for FCS-treated cells. In the case of rheumatoid synovial cells, the degree of adhesion was similar for drug- and FCS-treated cultures. Moreover, FN and RA had little effect on the spreading compared to FCS. Given these results, it would appear that synoviocytes differ in their behaviour from usual fibroblastic models.

[Biological criteria of denutrition. Search of significant parameters for diagnosis and management in surgical departments]

Assessment of the nutritional status of surgical patients with a mean weight loss of 11.5 kg included determination of the following biochemical parameters: prealbumin, retinol-binding protein (RBP), serum vitamin A and serum zinc. Patients' immunological status was investigated by delayed hypersensitivity skin tests. Prealbumin and RBP are decreased in patients. RBP levels are significantly lower than in controls: RBP therefore seems to be a better criterion of denutrition than prealbumin. Serum RBP and vitamin A concentrations are not always correlated in patients; for instance, in malabsorptions, the sharp fall in serum vitamin A is isolated. The decrease in mean serum zinc concentrations is minor. Three patients have positive skin tests with severe biochemical disturbances; only serum zinc concentrations are normal and correlated with the results of skin tests. Interpretation of investigations in surgical patients is dependent on the cause of weight loss. However, biochemical and immunological assessment of the nutritional status can demonstrate specific deficits and improve preoperative nutrition.

[Serum-ferritin assay in patients over seventy. A study on fifty-eight non anemic subjects and thirty-five anemic patients (author's transl)]

An immuno-enzymatic assay of serum ferritin was performed in subjects over 70 years of age. Wide variations in serum ferritin levels were demonstrated in the non-anemic group (17-510 ng/ml). This makes interpretation of results very difficult. In anemic patients a negative correlation was found between serum ferritin levels and TIBC (Total Iron Binding Capacity). When TIBC is under 42 mumol/l or above 63 mumol/l the two values are so closely correlated that serum ferritin assay does not provide any additional information for the diagnosis of anemia. On the contrary when TIBC is between 42 and 63 mumol/l serum ferritin can allow an estimation of tissue iron storage particularly in absolute iron deficiencies.

Fibroblast cultures in experimental disturbed metabolic conditions. effects of anti-inflammatory drugs

Fibroblasts in normal metabolic conditions constitute a simple cellular model for the study of anti-inflammatory drugs in culture, but do not take into account the factors related to the acute inflammatory reaction. A new approach was tried in submitting the fibroblasts to the action of a mouse peritoneal exudate or selected activated macrophages. Disrupted peritoneal material was inoculated to cultures in a volume representing a number of cells corresponding to 25 or 50% of fibroblast concentration at day 0 of the experimental time. Three anti-inflammatory drugs were retained to study their effects on proliferation and metabolic parameters: hydrocortisone, indomethacin and a newly-described molecule, the methoxybenzalthiosemicarbazone (MBT). At day 0, 1, and 2, fibroblasts were counted and total cellular protein and cellular glycolytic activity were determined. 4.5 X 10(-5) M hydrocortisone and MBT protected the fibroblast from the antiproliferative action of peritoneal exudate whereas in experiments using activated macrophage homogenate, all drugs exerted a protective and stimulatory effect.