Anti-arthritic properties of FK506 on collagen-induced arthritis in rats

Objective and design:To determine the effect of FK506 (tacrolimus) on paw inflammation, TNF- expression in joint, and bone and cartilage destruction in type II collagen-induced arthritis (CIA) model in rats.Methods:CIA was induced by immunization of female Lewis rats with an emulsion of bovine type II collagen and incomplete Freunds adjuvant. Paw inflammation was assessed by the increase in paw volume. Tumor necrosis factor (TNF) - expression in hind knee joint was assessed by immunohistochemical analysis. Lesions of bone and cartilage were assessed on the basis of histological change in knee joint, radiographic analysis in hind paw, bone mineral density in femora and proteoglycan contents in the cartilage of femoral heads. FK506 at doses of 1, 1.8 and 3.2 mg/kg or its placebo formulation was orally administered to rats for 28 days from the day after immunization (n = 10). Effect of FK506 was compared with that of vehicle (distilled water).Results:FK506 at a dose of 1.8 mg/kg significantly suppressed paw swelling (p < 0.01) and histological change in knee joint (p < 0.05). Tumor necrosis factor (TNF)- was mainly expressed in the region with a marked infiltration of inflammatory cells in the hind knee joint. FK506 (3.2 mg/kg) markedly reduced TNF- expression. FK506 at a dose of 1.8 mg/kg suppressed radiographic changes in hind paw (p < 0.05) and also recovered the decrease in bone mineral density in the femora (p < 0.05). Proteoglycan contents in the cartilage of femoral heads were determined to evaluate the cartilage destruction more quantitatively and found to significantly decrease in CIA rats. FK506 at a dose of 1.8 mg/kg recovered the loss of proteoglycan contents (p < 0.01).Conclusion:These results show that FK506 is effective in suppressing inflammation, TNF- expression in joint, and damage to bone and cartilage in rat CIA, and may be useful in the treatment of rheumatoid arthritis.     

Prostagiandin E1 and F2 α levels during development of shock induced by plague toxin

Laboratory of the Molecular Basis of Pathogenesis of Infectious Diseases, Central Research Institute of Epidemiology, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. I. Pokrovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 105, No. 3, pp. 313–315, March, 1988.     

Synoviocytes in chronic synovitis in situ and cytokine stimulated synovial cells in vitro neo-express α1, α3 and α5 chains of β1 integrins

The expression of the 1 integrins was examined immunohistochemically in synoviocytes from normal synovial membrane and from chronic synovitis of different aetiology and intensity. Normal synoviocytes were 61-positive but lacked 1 through 5. In mild inflammation type A synoviocytes neo-expressed 1, 3, and 5 chains. In severe inflammation both type A and B synoviocytes expressed 3, 4, 5, and 6 chains. The effects of inflammatory cytokines, as single agents or in combination, on the 1 integrin expression in cultured normal synoviocytes was determined by immunocytochemistry and flow cytometry. The 1 chain, while absent in unstimulated synoviocytes, was induced by interleukin-1 (IL-1), tumour necrosis factor- (TNF-), and interferon- (INF-). This effect was enhanced by combining IL-1 and TNF-. Expression of the 3 chain was up-regulated by IL-1 and, more intensely, by IFN-. Transforming growth factor (TGF-) inhibited the up-regulating effect of IL-1 and antagonized the effect of IFN- on 3 chain expression. Expression of the 5 chain was up-regulated significantly by co-stimulation through IL-1 together with TGF- or TNF-. Thus, the 1 integrin profile of cytokine activated synoviocytes in vitro resembled that of synoviocytes in synovitis in situ. These data suggest that IL-1, TNF-, IFN-, and TGF- are likely to be among the effectors regulating 1 integrin expression in synoviocytes in vivo.     

Cow milk angiogenin induces cytokine production in human blood leukocytes

Angiogenin isolated from cow milk induces the production of cytokines IL-1, IL-6, and TNF- in human leukocytes; the level of production of each cytokine depends on the concentration of the preparation, and the dynamics of production depends on the time from the beginning of induction. Simultaneous treatment with angiogenin and phytohemagglutinin had an additive effect on the production of cytokines, the time of this effect manifestation being individual for each cytokine.     

Effect of “flow anoxia” and “non flow anoxia” on the NAD/NADH redox state of the intact brain cortex of the cat

In the present study, we compared the nicotin-amide adenine dinucleotide (NAD) reducing potencies of flow anoxia and non flow anoxia in the cat brain cortex. In animals anaesthetized with alpha-D-glucochloralose flow anoxia and non flow anoxia were produced by ventilating for 2 and 25 min, respectively, with nitrogen gas. Following non flow anoxia, the brain cortices of dead animals were superfused with oxygen saturated artificial cerebrospinal fluid (mock CSF), and subsequently with CSF containing various concentrations (10^–3–10^–1 M) of potassium cyanide. NADH (reduced NAD) fluorescence of the brain cortex was measured through a cranial window with microscope fluororeflectometer. Ventilating the animals for 2 and 25 min with nitrogen gas increased cortical NADH fluorescence (NAD reduction) by 43.5±2.8% and 135.3±6.1%, respectively. Oxygen saturated CSF superfusion of the ischemic brain cortex restored the cortical NAD/NADH redox state to the preanocic level (oxidation of NADH). 10^–1 M cyanide, applied after superfusion of the brain cortex with oxygen saturated CSF resulted in comparable NAD reduction to that produced by non flow anoxia. On the basis of these findings it is suggested that non flow anoxia leads to much greater cortical NAD reduction than flow anoxia, because oxygen tension in the cortex may not fall to zero mm Hg during nitrogen anoxia lasting for 2 min. Besides this, a more pronounced substrate mobilization and acidosis may also contribute to the greater NAD reducing potency of non flow anoxia. Finally, since 10–15 min after the death of the animal the cerebral carbohydrate reserves are completely exhausted, and in our experiments non flow anoxia, reoxygenation of the ischemic brain cortex and inhibition of the cortical mitochondrial electron transport by cyanide (10^–1 M) resulted in comparable redox state changes (as far as their magnitude is concerned), it is concluded that the recorded changes in NADH fluorescence were of mitochondrial origin.     

Comparison of two models of bleomycin-induced lung fibrosis in mouse on the level of leucocytes and T cell subpopulations in bronchoalveolar lavage

Bleomycin produces pulmonary fibrosis in mice when given as a single intratracheal instillation or as multiple subcutaneous injections. Both models are associated with a significant deposition of collagen in the lungs but differ in the location of the initial lesions. Intratracheal instillation of bleomycin directs lesions to peribronchial or peribronchiolar sites, whereas subcutaneous injection produces lesions in subpleural and perivascular locations. It was therefore of interest to analyse the bronchoalveolar lavage (BAL) fluid for differences in the cellular composition, especially of intraepithelial T lymphocytes characterised by the expression of the integrin E7.Intracheal instillation of bleomycin induced a 5 to 6 times higher number of neutrophils and lymphocytes in BAL fluid than the subcutaneous model. Furthermore, intratracheal instillation of bleomycin induced the infiltration of eosinophilic neutrophils, a peculiar subtype of neutrophils often found in rodents, which were not found in BAL after subcutaneous injection of bleomycin. In both models of bleomycin injection, however, CD4⁺, CD8⁺, NK, and T lymphocytes were detected with dominance of the CD4⁺ T cell population. Analysis of the expression of the integrin E7 revealed similar numbers of E7⁺ cells in the CD4⁺ and T cell populations in both models but significantly lower numbers of E7⁺ T cells were found in the BAL fluid within the CD8⁺ T cell population after subcutaneous injection of bleomycin compared to intratracheal instillation.These results show that a difference in route of bleomycin administration not only causes changes in the localisation of the lesions but that this variation may be reflected in alterations within the BAL leucocyte population especially within the intraepithelial T lymphocytes.     

Effects of aging on the mechanical threshold of rat skeletal muscle fibers

Mechanical threshold was measured in vitro in extensor digitorum longus (EDL) muscle fibers from rats of 3–4 and 29 months of age, by means of a two microelectrode point voltage clamp. The potential needed for evoking a barly visible contraction was determined using depolarizing command pulses of 5–500ms duration. At each pulse duration, the EDL fibers from aged rats contracted at a significantly more negative potential than did those from the younger adult rats. Accordingly, the strength duration curve of the aged EDL was significantly shifted towards more negative potentials compared to that for adult rats. The rheobase voltages estimated from the fit of such curves were –62.6±0.81mV and –57.1±0.87mV in aged ana adult EDL fibers, respectively. The data suggest that changes in excitation-contraction coupling parallel the prolongation of contractile times observed during aging in mammalian skeletal muscle. These results are consistent with the known reduction in rate and extent of Ca⁺⁺ uptake by sarcoplasmic reticulum in aged rats.     

Regulatory T cell-subset imbalance in chronic active hepatitis

Three monoclonal anti-T-cell antibodies, specifically directed against total T cells (OKT3), inducer-helper T cells (OKT4), and suppressor/cytotoxic T cells (OKT8), were used in this study to analyze peripheral T-cell subsets in hepatitis B surface antigen (HBsAg)-positive and -negative chronic active hepatitis (CAH) patients. Results showed that a clear-cut difference exists in the distribution of peripheral T cells of these two groups of subjects. HBsAg-positive CAH patients had a numerical predominance of peripheral T lymphocytes expressing the characteristics of cytotoxic/suppressor T cells. In contrast, patients with autoimmune HBsAg-negative CAH exhibit a predominance of OKT4⁺ T cells, namely, the helper-inducer T-cell subset. In addition, high numbers of circulating doubly labeled cells (expressing both the OKT4 and the OKT8 xenoantigens) were detected in some of the HBsAg-positive and HBsAg-negative CAH patients studied.     

Radioautographic identification of lactogen binding sites in rat median eminence using 125I-human growth hormone: Evidence for a prolactin “short-loop” feedback site

Summary The binding characteristics of human growth hormone were exploited to identify radioautographically lactogen binding sites in the rat median eminence. Following systemic injection ¹²⁵I-human growth hormone bound preferentially to the lateral palisade zone, a region of median eminence rich in dopamine and LHRH. Coinjection of ¹²⁵I-human growth hormone with an excess of unlabeled human growth hormone or ovine prolactin, but not bovine growth hormone, competitively blocked ¹²⁵I-human growth hormone binding to the external median eminence. These observations provide direct evidence of recognition sites for lactogenic hormones in a discrete region of the median eminence associated with hypothalamic regulation of hypophyseal prolactin and luteinizing hormone secretion. Median eminence lactogen binding sites may mediate presumed direct effects of lactogenic hormones on the reproductive functions of the hypophysiotropic hypothalamus.A preliminary report of these findings was presented at the Annual Meeting of the Canadian Society for Clinical Investigation, February 5, 1979, Montreal, and appeared in Clinical Research 26, 874A (1979)     

Inverse behaviour of "synaptic" ribbon and spherule numbers in the pineal gland of male guinea-pigs exposed to continuous illumination

Summary There is increasing evidence that pineal synaptic ribbons are a heterogeneous population of organelles. In addition to synaptic ribbons (SR) sensu stricto, which consist of an electron-dense rod surrounded by electronlucent vesicles, synaptic spherules (SS) exist, the electrondense core of which is round and much wider than that of the SR. In the guinea-pig SR and SS numbers exhibit an inverse day/night rhythmicity. To gain more insight into the functional significance of SR and SS, guinea-pigs were exposed to continuous illumination for approximately 4 months (LL) and the respective structures in the pineal gland were quantitated under the electron microscope and compared with control animals kept under a lighting regiment of 12 h light and 12 h dark. It was found that SR numbers increase following LL whereas SS numbers decrease. The proximal, intermediate and distal parts of the dumbbell-shaped organ respond differently. The increase in SR numbers is significant in the distal and intermediate regions only, whereas the decrease in SS numbers is significant in the proximal and the intermediate regions only. Within each pineal region analyses of parenchymal subareas measuring 65 m by 65 m exhibit an inverse correlation of SR and SS numbers indicating that there are parenchymal domains in which either SR or SS predominate. Morphometric analyses of a number of pinealocytic parameters reveal minor differences between different pineal regions and that exposure to LL does not strikingly affect the pinealocyte perikarya. By contrast, the numbers of pinealocyte processes increase significantly after LL in the distal and intermediate, but not the proximal region of the pineal gland. These observations suggest structural and functional differences between different parts of the guinea-pig pineal gland.     

Synergistic effects of tumour necrosis factor-α and interferon-γ on feline haemopoietic progenitors

Pathogenic mechanisms that underlie feline leukaemia virus subgroup-C (FeLV-C) induced erythroid aplasia are unknown. FeLV-C infection is associated with higher serum levels of interferon- (IFN-) and tumour necrosis factor- (TNF-), which may act synergistically to cause haemopoietic suppression. In the present studies, the synergistic effects of TNF- and IFN- on feline bone marrow progenitors in vitro were evaluated. Bone marrow mononuclear cells from specific-pathogen-free cats were exposed to TNF- (100 and 200 pg/ml) and IFN- (100 or 200 units/ml), alone or in combination, for 2 h before plating for clonal assays of colony forming units. Our results show that TNF- and IFN- in combination caused marked suppression of feline colony forming units-erythroid (CFU-E), burst forming units-erythroid (BFU-E), and colony forming units-fibroblasts (CFU-F), whereas colony forming units-granulocyte/macrophage (CFU-GM) were minimally affected. The same concentrations of TNF- and IFN- alone had minimal effects on CFU-E, BFU-E and CFU-F. These results suggest that TNF- and IFN- may play a significant role in regulating haemopoiesis in cats and may be involved in the pathogenesis of erythroid aplasia in cats infected with feline leukaemia virus.     

Dependence of the degree of stress-induced heart damage in endogenous β-endorphin levels during preliminary adaptation

Laboratory of Radionuclide Methods of Investigation, Research Institute of Cardiology, Tomsk Scientific Center, Academy of Medical Sciences of the USSR. (Presented by Academician of Academy of Medical Sciences of the USSR, R. S. Karpov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 6, pp. 662–665, June, 1989.     

Flow Cytometric Analysis of In Vitro Proinflammatory Cytokine Secretion in Peripheral Blood from Multiple Sclerosis Patients

The cytokines, interferon- (IFN-), tumor necrosis factor- (TNF-rpar;, and interleukin-2 (IL-2) are important endogenous proinflammatory proteins and have been linked to disease activity in multiple sclerosis. In this study, we use flow cytometric methodology to compare the secretion of IFN-, IL-2, and TNF- from peripheral blood-derived T cells of multiple sclerosis patients to the secretion in healthy controls. The percentages of IFN-, IL-2, and TNF- secreting cells are not significantly different between multiple sclerosis patients and controls. However, the TNF- secreting CDS cell percentage is correlated with the IFN- and IL-2 secreting CD3 cell percentages in multiple sclerosis patients. In the controls, only the TNF- secreting CD3 cell percentage is correlated with IFN-. These findings show that correlated secretion of cytokines occurs in multiple sclerosis and suggest that concerted intercytokine interactions may play an important role in the disease.