Biomedical subjects
Publications and source records attributed to T M Hansen.
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Granulation tissue was produced in rats by subcutaneous implantation of viscose cellulose sponges. Treatment with cyclophosphamide in a dose of 10 mg/kg/day for 14 days caused an increase in acid soluble OH-proline and a decrease in alpha/beta ratio of acid soluble collagen of granulation tissue. Forty-two days of continuous cyclophosphamide treatment caused a decrease in dry weight, in free OH-proline, and in salt soluble OH-proline in granulation tissue. These findings are in accordance with previous observations of a decreased collagen synthesis and an inhibited collagen degradation in granulation tissue after cyclophosphamide treatment. In skin, the only change after cyclophosphamide was a decrease in total content of OH-proline and an increase in alpha/beta ratio of acid soluble collagen after 42 days of treatment. No effect of the subcutaneous sponge implantation was observed on the collagen variables in the skin. In comparison with unstarved controls, a reduction in dry weight and in free OH-proline in granulation tissue, as well as an increase in salt soluble OH-proline in the skin were observed 28 days after a 14-day treatment with cyclophosphamide. These observations indicate a sustained effect of cyclophosphamide on collagen 28 days after cessation of treatment. In addition the thermal stability of rat tail tendons was decreased 28 days after withdrawal of cyclophosphamide to the same extent as after starvation for 42 days and after 42 days of continuous cyclophosphamide treatment. It is concluded that the cyclophosphamide-induced collagen alterations, which may be of importance in the anti-inflammatory action of cyclophosphamide, are only in part reversible, 28 days after cessation of 14 days of cyclophosphamide treatment.
Cyclophosphamide was injected intraperitoneally into rats in doses of 6 or 10 mg/kg/day. The controls had daily intraperitoneal injections of physiological saline. After 14 days of treatment, granulation tissue was produced by subcutaneous implantation of viscose cellulose sponges. The treatment with cyclophosphamide and physiological saline was continued in different sequences for a further one or two 14-day periods. The rats were killed 14 or 28 days after the sponge implantation. Cyclophosphamide caused a decrease in body weight, in the number of leucocytes, in granuloma dry weight and in the granuloma content of free OH-proline while the water percentage increased. Ten mg/kg/day of cyclophosphamide had a more pronounced effect than 6 mg/kg/day. The results are consistent with an inhibitory effect of cyclophosphamide on granuloma formation and on the degradation of collagen. Accordingly, measurements of collagenolytic activity in granulation tissue after culture in vitro suggested an inhibition of collagenolysis after cyclophosphamide treatment. No effect of pretreatment was observed, and the effect of cyclophosphamide was independent of whether cyclophosphamide was given during the early or late phase of granulation tissue production.
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Granulation tissue was produced in rats by subcutaneous implantation of viscose cellulose sponges. Cyclophosphamide 10 mg/kg was given daily intraperitoneally to 15 rats from the day of sponge implantation. Fifteen rats served as pair-fed controls, and 15 rats served as non-starved controls. After 14 days of treatment the animals were decapitated. Groups of 3 rats were given 50 muci 14C-proline intraperitoneally 1, 3, 6, 12, or 24 hours before death. The aorta, skin, and granulation tissue were examined. Cyclophosphamide caused no effect on collagen of the aorta, while in skin, the only detectable effect was a decrease in 14C-OH-proline biosynthesis. In granulation tissue, cyclophosphamide caused a fall in the dry weight, a decrease in 14C-proline uptake and 14C-OH-proline synthesis, as well as an increase in the alpha-amino nitrogen to OH-proline ratio in purified collagen. These results indicate that cyclophosphamide inhibits the synthesis of proteins, including collagen, and inhibits the hydroxylation of proline in collagen. No effect of cyclophosphamide could be detected on the amount of salt soluble OH-proline or on collagen cross-linking. The registered effects of cyclophosphamide on granulation tissue is probably of importance with regard to the anti-inflammatory action of cyclophosphamide. This action as well as the tissue differences in the sensitivity of cyclophosphamide may be of relevance to the clinical application of cytostatics in rheumatological diseases.
Thirteen patients, aged 27 to 70 years, with definite or classical rheumatoid arthritis were treated with penicillamine for six months. Skin biopsies and blood samples were compared with a clinical evaluation before and after therapy. The analyses of the skin included determinations of total collagen, thermal reaction of collagen, salt soluble collagen, in vitro uptake of 14C-proline and synthesis of 14C-hydroxyproline, as well as determinations of nucleic acids and proteoglycans. Serum concentrations of acute phase reactants, immunoglobulins, complement C3 and C4, rheumatoid factor, and iron, copper, and zinc were also determined. A positive correlation was found between clinical improvement and a fall in the number of granulocytes, a decrease in the concentration of acute phase reactants and serum copper, and an increase in salt soluble collagen of the skin. The total skin collagen decreased during treatment with penicillamine. The changes in skin collagen may reflect a generalized effect of penicillamine on collagen. These alterations may be part of an anti-inflammatory action of penicillamine.
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Granulation tissue was produced in rats by subcutaneous implantation of cellulose sponges. The effect of daily intraperitoneal injections of cyclophosphamide or azathioprine on rat skin and granulation tissue was examined after 14 and 42 days. Skin biopsies from patients with glomerulonephritis were analyzed before and after 42 days of treatment with cyclophosphamide or placebo. In the rats, cytostatic treatment caused an increase in the dry weight of the skin, and azathioprine increased the dry weight and the protein content of the granulomas. The increase in the dry weight was accompanied by a decrease in water percentage. The alpha-amino nitrogen/OH-proline ratio in purified acid soluble collagen from skin and granulation tissue increased with the dose and duration of cytostatic treatment. No effect on the aldehyde content was observed. Cyclophosphamide caused a decrease in the alpha/beta ratio in acid soluble collagen from granulation tissue, but not in the collagen from the skin. Salt soluble collagen was increased in the skin after 14 days of cytostatic treatment, but remained unchanged in the granulation tissue. In human skin cyclophosphamide caused no statistically significant changes in the amount of salt soluble or total collagen. It is concluded, that daily treatment of rats with cyclophosphamide or azathioprine from 14 to 42 days seems to inhibit the catabolic processes in the skin and granulation tissue, to decrease the hydroxylation of proline in collagen, and to inhibit the intermolecular cross-linking in collagen.?222
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Granulation tissue in rats was produced by subcutaneous implantation of viscose cellulose sponges. Granulomas, aortae, and skin samples were taken 4, 8, 14, 22, 33, and 42 days after the sponge implantation and compared with age-matched non-operated rats. 14C-proline was given 4 hours before death to animals killed on day 0, 14, and 42. The 14C-OH-proline activity in salt insoluble collagen was higher in granulation tissue and aorta than in skin. This indicates a faster formation, or an increased stability of the intermolecular cross-links in granulation tissue and aorta, than in skin. The percentage of free OH-proline was than in skin, reflecting a relatively increased collagen degradation in granulation tissue. An increased collagen degradation may also, in part, explain a registered higher alpha/beta ratio in collagen from granulation tissue than from skin, as well as the increase in alpha/beta ratio in the older granulomas. The sponge implantation did not affect the collagen of aorta and skin, but caused a decrease in the dry weight of aorta and skin, and an increase in the number of granulocytes in the blood.
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