Do active substances of thymus influence the processes of aging? VIII. Cerebral superoxide dismutase activity and malonyl dialdehyde concentration in aging mice treated with embryonal and early fetal thymic calf extracts (ETCE) and mature calf thymic extracts (thymex L and TFX).

Cerebral superoxide dismutase (SOD) activity and malonyl dialdehyde (MDA) concentration were determined in 450 day female BNe strain mice. These animals were previously treated with 45 injections of: 1. embryonal and early fetal thymic calf extracts (ETCE) in single doses of 1.0 mg (group E) and 7.5 mg (group EE) protein per mouse; 2. Thymex L in the same doses (groups T and TT, respectively); 3. TFX in a single dose on 1.0 mg protein per animal. All applied thymic extracts, independently of the kind and dose, caused a fall in brain SOD activity. A statistically significant decrease in MDA concentration was found in the brains of E group mice. A clinical implication of the results has been suggested.

Do active substances of the thymus influence the processes of aging? I. Effects of treatment with embryonal and early fetal thymic calf extracts (ETCE) on some organs of grown-up young mice.

Our previous investigations indicated that embryonal and early fetal thymic calf extracts (ETCE), unlike those obtained from adult thymus, cause lymphopenia and hypogammaglobulinemia, counteract anaphylactic shocks and prolong the survival of allografts and xenografts in adult rodents. This paper presents the level of unsaturated fatty acid peroxides and the morphology of some organs in adult mice treated parenterally with ETCE. ETCE treatment resulted in the fall in the level of cerebral and splenic unsaturated fatty acid peroxides. Histology of thymus, liver and spleen in mice injected with ETCE remained similar to that of corresponding neonatal mouse organs. Experimental results, supplemented by such previous observations as longevity of some animals treated with ETCE, disappearance of presbyopia and climacteric symptoms in people treated with embryonal thymus per os, suggest that active substances produced by embryonal and early fetal thymus not only affect the immunological system but also interfere with the processes of organ differentiation and aging.

The effect of embryonal thymic calf extracts on neonatally thymectomized mice and on mice lethally irradiated with gamma rays.

The effect of embryonal thymic calf extracts (ETCE) on mice thymectomized at birth was investigated. ETCE was found to induce an increase in leukopenia and a decrease in the level of serum gamma globulins; it also reduced survival time in mice. The effect of ETCE on lethally irradiated mice was also examined. Only long-term administration of ETCE prior to gamma irradiation at 750 rad prolonged the survival time of mice (40% permanent survival) as compared with irradiated controls; the leukocytes from mice retained mitotic capability. Neither long-term treatment with ETCE prior to irradiation at 1000 rad, nor short-term administration prior to 750 rad affected survival time. ETCE administered after irradiation of mice with 750 rad caused a rapid decrease in blood leukocytes and a significantly lowered survival time.