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3.
Arch Toxicol ; 77(4): 194-200, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12698234

RESUMO

Chronic cholestasis is characteristic of many human liver diseases. Renal injury has been often associated with this type of disease. The aim of this study was to evaluate the effect of cholestasis on kidney mitochondrial bioenergetics following in vivo chronic administration of alpha-naphthyl-isothiocyanate (ANIT), a known cholestatic agent. Serum markers of renal injury, kidney morphology and endogenous adenine nucleotides were measured in ANIT-treated rats (80 mg/kg per week s.c. for 16 weeks). Changes in membrane potential and mitochondrial respiration as well as alterations in mitochondrial calcium homeostasis were monitored. Cholestatic animals shown no alterations in renal morphology when compared with control. Additionally, following chronic ANIT administration, no significant alterations in mitochondrial respiratory function have been shown. The phosphorylation capacity of cholestatic kidney mitochondria was enhanced. Associated with these parameters, mitochondria from treated animals exhibited a decreased susceptibility to disruption of mitochondrial calcium homeostasis, due to permeability transition induction. These data suggest that, despite being submitted to chronic treatment with ANIT, kidney mitochondria from cholestasis-induced rats present some defense mechanisms to circumvent this aggression. They show improved phosphorylative capacity and, moreover, a decreased susceptibility to mitochondrial permeability transition induction, probably due to adaptative mechanisms of calcium transport.


Assuntos
1-Naftilisotiocianato/toxicidade , Colestase Intra-Hepática/induzido quimicamente , Metabolismo Energético/efeitos dos fármacos , Rim/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , 1-Naftilisotiocianato/administração & dosagem , Nucleotídeos de Adenina/metabolismo , Animais , Cálcio/metabolismo , Colestase Intra-Hepática/metabolismo , Colestase Intra-Hepática/patologia , Modelos Animais de Doenças , Feminino , Injeções Intraperitoneais , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/fisiologia , Rim/metabolismo , Rim/patologia , Potenciais da Membrana/efeitos dos fármacos , Mitocôndrias/metabolismo , Dilatação Mitocondrial/efeitos dos fármacos , Fosforilação , Ratos , Ratos Wistar
4.
Cancer ; 70(11): 2703-12, 1992 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-1423201

RESUMO

BACKGROUND: Treatment of cancer with multiple-drug chemotherapy regimens or radiation therapy can cause either temporary azoospermia of various durations or permanent azoospermia in young men. METHODS: To identify which drugs in which doses contribute to long-term or permanent azoospermia, semen analyses were done on patients with Ewing and soft tissue sarcomas before, during, and after treatment with either CYADIC (cyclophosphamide, doxorubicin, and dacarbazine), or CYVADIC (vincristine added to CYADIC). Some patients also received other drugs or radiation therapy. RESULTS: From pretreatment levels that were similar to those of control subjects, sperm production declined to azoospermia within 4 months of treatment. Sperm production returned in some patients after treatment; 40% of men recovered to normospermic levels by 5 years after treatment. Few patients showed continued recovery of sperm production after that time. The cumulative dose of cyclophosphamide was the most significant determinant of recovery to normospermic levels; approximately 70% of those who had received doses less than 7.5 g/m2 (median, 4.1 g/m2) recovered, but only 10% recovered when doses exceeded 7.5 g/m2. CONCLUSIONS: Thus, a risk of permanent sterility is associated with the use of the CYADIC and CYVADIC regimens in young men, especially when the cumulative dose of cyclophosphamide is greater than 7.5 mg/m2.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida/efeitos adversos , Sarcoma de Ewing/tratamento farmacológico , Sarcoma/tratamento farmacológico , Neoplasias de Tecidos Moles/tratamento farmacológico , Contagem de Espermatozoides/efeitos dos fármacos , Adulto , Ciclofosfamida/administração & dosagem , Dacarbazina/efeitos adversos , Doxorrubicina/efeitos adversos , Humanos , Masculino , Oligospermia/induzido quimicamente , Fatores de Tempo , Vincristina/efeitos adversos
6.
Cancer ; 63(11): 2115-23, 1989 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-2720562

RESUMO

Because treatment with surgery and combination chemotherapy produces a high cure rate in young men with osteosarcoma, their subsequent reproductive function is an important concern. Semen analyses of osteosarcoma patients, therefore, were performed before, during, and after treatment with the PADIC regimen consisting of cisplatin, Adriamycin (doxorubicin), and dacarbazine or, in some cases, the PADIC regimen plus additional drugs. Results showed that semen volume was not affected and that sperm motility was reduced only during treatment. Although nearly all patients were rendered azoospermic during treatment, sperm production resumed in 30 of 32 patients examined at least 2 years after treatment. Analysis with correction for censored data indicates that, in 78% of treated men, sperm counts will return to more than 10 million/ml. The percentage of men whose sperm counts recovered to normal was lower for those receiving cisplatin dosages greater than or equal to 600 mg/m2; no trends were observed with Adriamycin and dacarbazine dosages. The inclusion of additional drugs such as methotrexate, bleomycin, dactinomycin, or cyclophosphamide (less than 4 g/m2) did not significantly affect the recovery of spermatogenesis. We conclude that the risk of long-term infertility from treatment with the PADIC regimen is low.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Osteossarcoma/tratamento farmacológico , Espermatogênese , Adolescente , Adulto , Neoplasias Ósseas/fisiopatologia , Cisplatino/administração & dosagem , Dacarbazina/administração & dosagem , Doxorrubicina/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Osteossarcoma/fisiopatologia , Sêmen/análise , Sêmen/efeitos dos fármacos , Contagem de Espermatozoides , Espermatogênese/efeitos dos fármacos
7.
Cancer Res ; 47(4): 1093-7, 1987 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-3542201

RESUMO

Protection of testicular integrity against damage from cyclophosphamide (CY) by simultaneous treatment with a gonadotropin-releasing hormone (GnRH) analogue was reported in BALB/c mice (L.M. Glode et al., Lancet, 1: 1132-1134, 1981). This approach has been used as the basis for clinical trials in various treatment centers (D. H. Johnson et al., Blood, 65:832-836, 1985) in an attempt to prevent iatrogenic sterility in males. This study aims at duplicating the original findings and obtaining quantitative data on spermatogonial killing by CY, and possible protection by GnRH, of differentiating and stem cell spermatogonia. Mice were treated with 23 daily injections of 0.4 micrograms D-leucine-6 GnRH, and with 200 mg/kg CY on Days 8, 15, and 22. Three additional groups of mice received phosphate-buffered saline and bovine serum albumin only, GnRH only, and CY only. Animals were killed at 29 days after the last injection to determine the number of late spermatids in testicular homogenates, and at 56 days for histological measurement of the ratio of elongated spermatids to Sertoli cells in the tubules. The twenty-ninth day assay was a measure of damage to differentiating spermatogonia, whose killing results in temporary sterility. The fifty-sixth day point assay assessed damage to stem spermatogonia, whose killing results in long-term or permanent sterility. Sperm counts at 29 days were identical in saline-treated control mice and GnRH-treated mice; no sperm were present in the CY-treated mice, both with and without GnRH. Thus, killing of differentiating spermatogonia by CY is not prevented by GnRH treatment. Similarly, counts of spermatids at 56 days showed no difference between saline- and GnRH-treated groups; a reduction to approximately 40% of control counts was observed equally with CY and CY plus GnRH treatments. Since GnRH treatment did not alter spermatogonial kinetics in BALB/c mice, it is not surprising that it did not protect against CY-induced damage. Thus, the mouse is not a suitable model for analyzing such effects of GnRH on spermatogenesis, and further studies in other experimental animals are needed if they are to be used as a rationale for clinical administration of GnRH to cancer patients.


Assuntos
Ciclofosfamida/toxicidade , Hormônio Liberador de Gonadotropina/farmacologia , Testículo/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/análogos & derivados , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Tamanho do Órgão/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos
8.
J Androl ; 6(4): 225-9, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3839780

RESUMO

The stages of spermatogenic cells killed by the single and fractionated administration of AMSA, an acridine derivative used in cancer chemotherapy, have been identified in the mouse. A wide range of doses, up to a total of 30 mg/kg, which is the LD50 for AMSA given in three daily injections, was employed. Survival of differentiating (types A1 through Intermediate) and stem spermatogonia was measured by sperm counts performed 29 and 56 days after treatment, respectively. The sensitivity of germ cells to AMSA at other stages of differentiation was determined by semiquantitative histologic analysis at 11 days after treatment. Significant killing of differentiating spermatogonia, types A2 through B, but only minor killing of stem cells and no toxicity to post-spermatogonial stages were observed with all treatment schedules. This pattern of differential sensitivity can explain the temporary azoospermia observed in man during AMSA treatment, which was followed by a return to normal sperm counts after cessation of therapy.


Assuntos
Aminoacridinas/farmacologia , Antineoplásicos/farmacologia , Espermatogênese/efeitos dos fármacos , Amsacrina , Animais , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Camundongos , Camundongos Endogâmicos C3H , Contagem de Espermatozoides , Espermatogônias/efeitos dos fármacos
9.
J Clin Oncol ; 2(6): 571-7, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6547167

RESUMO

The sperm production of 25 patients with Hodgkin's disease treated with mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) chemotherapy was studied retrospectively. All but two patients also received radiotherapy treatment to pelvic and/or non-pelvic fields. Sperm counts were obtained from patients treated either with three or fewer (MOPP-2 group) or with five or more (MOPP-6 group) chemotherapy cycles. Recovery of spermatogenesis following treatment-induced azoospermia was significantly higher among the MOPP-2 patients (Mann-Whitney rank sum test, p = 0.001). Patients in this group who did not receive pelvic irradiation appeared to have greater recovery rates (p = 0.06). The results suggest that three cycles of MOPP chemotherapy represent a maximum exposure compatible with the recovery of spermatogenesis.


Assuntos
Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica , Doença de Hodgkin/tratamento farmacológico , Espermatogênese/efeitos dos fármacos , Adolescente , Adulto , Antineoplásicos/uso terapêutico , Terapia Combinada , Doença de Hodgkin/fisiopatologia , Doença de Hodgkin/radioterapia , Humanos , Masculino , Mecloretamina/administração & dosagem , Mecloretamina/efeitos adversos , Pelve/efeitos da radiação , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Procarbazina/administração & dosagem , Procarbazina/efeitos adversos , Contagem de Espermatozoides , Espermatogênese/efeitos da radiação , Vincristina/administração & dosagem , Vincristina/efeitos adversos
10.
J Urol ; 130(5): 927-30, 1983 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6415299

RESUMO

The sperm production of 14 cancer patients who received doxorubicin was examined after cessation of therapy. Doxorubicin was used in several multiple-drug protocols for the treatment of various malignancies. Seven patients also received radiotherapy to different sites. Total cumulative doses of doxorubicin ranged from 145 to 625 mg./m.2. Sperm concentration, motility, morphology and the frequency of quinacrine-stained sperm with 2 fluorescent bodies (2F sperm) were measured 7 to 79 months after discontinuation of doxorubicin. Of the patients 6 remained azoospermic, 3 were oligospermic and 5 were normospermic. Sperm motility among the 8 patients with sperm ranged from 20 to 80 per cent. Morphology and 2F sperm distributions were not significantly different from controls. We conclude that, in contrast with the mechlorethamine, vincristine, procarbazine and prednisone protocol, active sperm production within relatively short recovery times is possible after treatment with protocols that include doxorubicin.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doxorrubicina/efeitos adversos , Oligospermia/induzido quimicamente , Espermatogênese/efeitos dos fármacos , Adulto , Terapia Combinada , Doxorrubicina/administração & dosagem , Humanos , Masculino , Neoplasias/terapia , Radioterapia de Alta Energia , Sêmen/análise , Motilidade dos Espermatozoides/efeitos dos fármacos , Fatores de Tempo
11.
Cancer ; 49(12): 2459-62, 1982 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-7074561

RESUMO

Spermatogenesis in a melanoma patient treated with 12 courses of acridinyl anisidide (AMSA) (20 mg/m2/course) was studied by monitoring sperm concentration, motility, and morphology at various phases of treatment. Chemotherapy was interrupted for 20 weeks between the ninth and tenth course. Sperm concentration and motility began to decline after the second course. At the third course, the percentage of morphologic abnormalities had increased to 86.5% from a pretreatment value of 57.8% (P less than 0.001). Azoospermia was observed at the sixth course and persisted until 12 weeks after the ninth course, when semen levels returned to pretreatment levels: 20 million/ml; 70% motility; 60.1% abnormal forms. Three weeks after the 12th course, the sperm count was reduced to 250,000/ml, motility to 5%, and abnormalities increased to 84.0%. The rapid recovery of normal spermatogenesis observed during the chemotherapy interruption indicates that AMSA has only a temporary, reversible effect on differentiating germinal cells with no toxicity to stem cells.


Assuntos
Aminacrina/efeitos adversos , Aminoacridinas/efeitos adversos , Antineoplásicos/efeitos adversos , Espermatogênese/efeitos dos fármacos , Adulto , Aminacrina/análogos & derivados , Humanos , Masculino , Melanoma/tratamento farmacológico , Espermatozoides/efeitos dos fármacos
12.
Cancer Res ; 42(1): 122-31, 1982 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7198505

RESUMO

The harmful effects of 14 chemotherapeutic drugs on spermatogenesis in the mouse have been evaluated by studies of testicular cell killing and morphological and genetic damage produced. Male mice were given drugs as single injections at various doses up to the toxic levels. Prednisone and 6-mercaptopurine produced little or no cytotoxicity. All other drugs tested killed differentiated spermatogonia. Of these, methotrexate, cyclohexylchlorethylnitrosourea, cis-platinum, and mechlorethamine did not show significant stem cell killing. Bischlorethylnitrosourea, chlorambucil, 5-fluorouracil, mitomycin C, antinomycin D, and procarbazine showed some stem cell killing. Triethylenethiophosphoramide (thio-TEPA) was the only drug in this group which killed large numbers of stem cells. Only 5-fluorouracil and cis-platinum killed spermatocytes, and only cis-platinum killed spermatids. Several drugs induced chromosome breaks in treated spermatocytes. Thio-TEPA was effective in inducing chromosome translocations in treated spermatocytes and probably also in spermatocytes which originated from surviving treated stem cells. It had been our hypothesis that the cytotoxic effects of these drugs on mouse testicular stem cells would correlate with the duration of azoospermia observed in patients. This was shown not to be the case. Thus, the cytotoxic effects of single injections of single chemotherapeutic agents on the mouse testis did not appear to be predictive of which drugs will cause long-term azoospermia in humans.


Assuntos
Antineoplásicos/farmacologia , Testículo/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Masculino , Camundongos , Espermatogênese/efeitos dos fármacos , Espermatogônias/efeitos dos fármacos , Testículo/patologia
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