Cyclosporin A causes impairment of the ventral prostate tissue structure of Wistar rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Alendronate therapy in cyclosporine-induced alveolar bone loss in rats

Background and Objective: Cyclosporine A is an immunosuppressive drug that is widely used in organ transplant patients as well as to treat a number of autoimmune conditions. Bone loss is reported as a significant side-effect of cyclosporine A use because this can result in serious morbidity of the patients. As we have shown that cyclosporine A-associated bone loss can also affect the alveolar bone, the purpose of this study was to evaluate the effect of the concomitant administration of alendronate on alveolar bone loss in a rat model.Material and Methods: Forty Wistar rats (10 per group) were given cyclosporine A (10 mg/kg, daily), alendronate (0.3 mg/kg, weekly), or both cyclosporine A and alendronate, for 60 d. The control group received daily injections of sterile saline. The expression of proteins associated with bone turnover, including osteocalcin, alkaline phosphatase and tartrate-resistant acid phosphatase (TRAP), and also the calcium levels, were evaluated in the serum. Analysis of the bone volume, alveolar bone surface, the number of osteoblasts per bone surface and the number of osteoclasts per bone surface around the lower first molars was also performed.Results: the results indicate that cyclosporine A treatment was associated with bone resorption, represented by a decrease in the bone volume, alveolar bone surface and the number of osteoblasts per bone surface and by an increase in the number of osteoclasts per bone surface and TRAP-5b. These effects were effectively counteracted by concomitant alendronate administration.Conclusion: It is concluded that concomitant administration of alendronate can prevent cyclosporine A-associated alveolar bone loss.

The effects of up to 240 days of tacrolimus therapy on the gingival tissues of rats - A morphological evaluation

Background: Tacrolimus, an immunosuppressive drug used in organ transplantation, has been reported not to induce gingival overgrowth. However, prevalence studies are limited, and the methods used for assessing gingival overgrowth varies among studies. Objective: The purpose of this study was to evaluate the effects of up to 240 days of tacrolimus therapy on gingival tissues of rats. Materials and methods: Rats were treated for 60, 120, 180 and 240 days with daily subcutaneous injections of 1 mg/kg body weight of tacrolimus. After histological processing, the oral and connective tissue, volume densities of fibroblasts (Vf), collagen fibers (Vcf) and other structures (Vo) were assessed in the region of the lower first molar. Results: After 60 and 120 days of treatment with tacrolimus, gingival overgrowth was not observed. The gingival epithelium, connective tissue, as well as the values for Vf, Vcf, and Vo were similar to those of the control rats (P > 0.05). After 180 and 240 days of the treatment, gingival overgrowth was associated with a significant increase in the gingival epithelium and connective tissue as well as an increase in the V f and Vcf (P < 0.05). Conclusions: Within the limits of the experimental study, it may be concluded that the deleterious side effects of tacrolimus on the gingival tissues of rats may be time-related. © 2007 Blackwell Munksgaard All rights reserved.

Desenvolvimento e caracterização de sistemas micro e nanoestruturados para a administração cutânea de acetato de dexametasona

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação morfométrica e estereométrica dos tecidos periodontais de ratos imunossuprimidos por Tracolimus (FK506)

Pós-graduação em Odontologia - FOAR

Heteropterys tomentosa (A. Juss.) infusion counteracts Cyclosporin a side effects on the ventral prostate

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Predictive Usefulness of Urinary Biomarkers for the Identification of Cyclosporine A-Induced Nephrotoxicity in a Rat Model

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efeitos preventivos do treinamento físico na expressão das proteínas Cox-2 e Vegf de ratos tratados com dexametasona

Dexamethasone is a synthetic glucocorticoid widely used to treat allergic and inflammatory processes. This drug is used in three main situations, are used to contain acute or chronic inflammatory processes, or like immunosuppressive drug's. In these cases the patient will receive high doses for a chronic period and, therefore, has a much greater chance of adverse side effects, such as hypertension, diabetes and dyslipidemia. Dexamethasone promotes deleterious effects on the arachidonic acid pathway, when administered in high doses, because it is a potent anti-inflammatory drug. We recently demonstrated that dexamethasone significantly reduces the protein expression of vascular endothelial growth factor (VEGF) in both skeletal muscle and heart, but the mechanisms involved remain unclear. Meanwhile, exercise has been shown to be effective against high blood pressure, diabetes and dyslipidemia, promoting, among other factors, the increase in VEGF and angiogenesis. One possible explanation for these effects would be the creation of new vessels mediated by inflammation, or by the stimulation of the formation of products of the metabolism of arachidonic acid (AA), such as prostaglandin E2 (PGE2) and VEGF, by increasing the stimulation of the enzymes cyclooxygenase 1 and 2 (COX-1 and COX-2). Little is known about the preventive effects of training on the action of dexamethasone in the arachidonic acid pathway. Therefore, the aim of this study was to determine whether aerobic exercise training, performed before and concomitant treatment with dexamethasone, was able to prevent the effects of the dexamethasone in the protein expression of COX-2 and VEGF. For this, we used young Wistar rats (n = 40) which were randomly divided into 4 groups: sedentary control (SC), sedentary and treated with dexamethasone (SD), trained control (TC) and trained and treated with dexamethasone (TD). These rats performed aerobic exercise training, 60% of maximum capacity, 5

Conversion of immunosuppressive monotherapy from cyclosporin A to tacrolimus reverses bone loss in rats

Tacrolimus is used for transplant patients with refractory graft rejection and those with intolerance to cyclosporin (CsA), without the disfiguring adverse effects frequently attributed to CsA therapy. Since we have shown that CsA-associated bone loss can also affect alveolar bone, the purpose of this study was to evaluate the effects of conversion of monotherapy from CsA to tacrolimus on alveolar bone loss in rats. Groups of rats were treated with either CsA (10 mg/kg/day, s.c.), tacrolimus (I mg/kg/day, s.c.), or drug vehicle for 60 and 120 days, and an additional group received CsA for 60 days followed by conversion to tacrolimus for a further 60-day period. Bone-specific alkaline phosphatase (BALP), tartrate-resistent acid phosphatase (TRAP-5b), calcium (Ca2+), interleukin (IL)-1 beta, IL-6, and tumor necrosis factor alpha (TNF-alpha) concentrations were evaluated in the serum. Analyses of bone volume, bone surface, number of osteblasts, and osteoclasts were performed. Treatment with CsA for either 60 or 120 days was associated with bone resorption, represented by lower bone volume and increased number of osteoclasts; serum BALP, TRAP-5b, IL-1 beta, IL-6, and TNF-alpha were also higher in these animals. After conversion from CsA to tacrolimus, all the altered serum markers returned to control values in addition to a significant increase of bone volume and a lower number of osteoclasts. This study shows that conversion from CsA to tacrolimus therapy leads to a reversal of the CsA-induced bone loss, which can probably be mediated by downregulation of IL-1 beta, IL-6, and TNF-alpha production.

Influence of post-transplant immunosuppressive therapy on gastrointestinal transit using biomagnetic method: a pilot study

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)