RESUMO
Background: In recent years, due to the increase in medical mal-practice complaints, the Sicilian Regional Health System has adopted procedures for the direct management of claims by each health facility with the aim of reducing the costs of insurance premiums and related taxes. Mandatory sentinel event monitoring is a crucial part of this strategy to improve patient safety and quality of care. The reported case relates to a laparoscopic myomectomy surgery performed by means of morcellation, a controversial technique. After the FDA's intervention in 2014, it is believed that morcellation may worsen the staging of the disease by spreading malignancies such as leiomyosarcoma into the abdomen. Case report: A 28-year-old woman, underwent laparoscopic surgery for uterine fibroids and an ovarian cyst removal in August 2018. Post-surgery, she was diagnosed with Leiomyoma. She returned to the hospital due to metrorrhagia and was discharged after a week. Persistent symptoms led to her readmission and subsequent exploratory laparoscopic surgery at another hospital. This resulted in a total hysterectomy and the discovery of uterine leiomyosarcoma, with FIGO STAGE IIIB staging. Despite chemotherapy, she passed away six months later. Discussion and Conclusions: This case highlights medical-legal issues. Informed consent for morcellation and its risks was not obtained. The morcellation technique was used, increasing cancer spread risk. The histopathological process was inadequate, with three biopsies leading to misdiagnosis. This could be medical malpractice, making providers legally responsible for the patient's deteriorating condition and the anticipation of possible death.
Assuntos
Laparoscopia , Leiomioma , Leiomiossarcoma , Imperícia , Morcelação , Miomectomia Uterina , Neoplasias Uterinas , Humanos , Feminino , Morcelação/efeitos adversos , Morcelação/legislação & jurisprudência , Adulto , Miomectomia Uterina/métodos , Laparoscopia/métodos , Imperícia/legislação & jurisprudência , Leiomioma/cirurgia , Neoplasias Uterinas/cirurgia , Leiomiossarcoma/cirurgia , Evolução Fatal , Histerectomia/legislação & jurisprudência , Histerectomia/métodos , Inoculação de Neoplasia , Cistos Ovarianos/cirurgiaRESUMO
The diagnosis of bland-looking spindle cell lesions of the breast is often challenging because there is a close morphological and immunohistochemical overlap among the different entities. The present review will discuss reactive spindle cell nodule/exuberant scar, nodular fasciitis, inflammatory pseudotumor, myofibroblastoma (classic type), lipomatous myofibroblastoma, palisaded myofibroblastoma, benign fibroblastic spindle cell tumor, spindle cell lipoma, fibroma, leiomyoma, solitary fibrous tumor, myxoma, schwannoma/neurofibroma, desmoid-type fibromatosis, dermatofibrosarcoma protuberans, low-grade fibromatosis-like spindle cell carcinoma, inflammatory myofibroblastic tumor and low-grade myofibroblastic sarcoma arising in the breast parenchyma. The pathologist should be aware of each single lesion to achieve a correct diagnosis to ensure patient a correct prognostic information and therapy. Accordingly representative illustrations and morphological/immunohistochemical diagnostic clues will be provided.
Assuntos
Neoplasias da Mama/diagnóstico , Carcinoma/diagnóstico , Dermatofibrossarcoma/diagnóstico , Fasciite/diagnóstico , Fibrossarcoma/diagnóstico , Neoplasias de Tecido Muscular/patologia , Neoplasias Cutâneas/diagnóstico , Mama/patologia , Neoplasias da Mama/patologia , Carcinoma/patologia , Dermatofibrossarcoma/patologia , Diagnóstico Diferencial , Fasciite/patologia , Feminino , Fibrossarcoma/patologia , Humanos , Neoplasias de Tecido Muscular/diagnóstico , Neoplasias Cutâneas/patologiaRESUMO
Nowadays, the histopathological study of surgical specimens is an essential part of the diagnostic work-up in aortic disease, and not only in characterizing the neoplastic forms. Despite increasing clinico-therapeutic complexity of aortic pathology, the criteria for histopathological diagnosis have not been properly updated over the years, with the result that we find inconsistent terminology and little standardization of diagnostic criteria. In light of this consideration, the SIAPeC-IAP Study Group of "Cardiovascular Pathology", in collaboration with the Association for Italian Cardiovascular Pathology, has created this consensus document, with the aim of defining the features of histopathological substrates in the main non-neoplastic aortopathies (atherosclerotic, "degenerative"/non inflammatory, and inflammatory) and of systematizing diagnostic criteria even for the rare tumours of the aorta and pulmonary artery. The principal aims of the project are defining histopathological diagnostic criteria, standard nomenclature and classification, methodology and reporting of histopathological study and handling of aortic specimens. In addiction, some current issues and new knowledge emerging from basic aortic research are debated, with the aim of promoting a "modern" and up-to-date view of aortic pathology.
Assuntos
Aorta/patologia , Doenças da Aorta/patologia , Patologia Clínica/normas , Neoplasias Vasculares/patologia , Vasculite/patologia , Consenso , Comportamento Cooperativo , ItáliaRESUMO
INTRODUCTION: Vascular endothelial growth factor (VEGF) is an endothelial cell mitogen. The objective of this study was to verify the proregenerative effects of VEGF in an experimental model of acute liver failure. MATERIALS AND METHODS: Sixty four rats that underwent intraperitoneal injection of carbon tetrachloride (CCl(4)) were randomly divided into two groups: group B animals received intravenous injection of VEGF(164) 1 hour following CCl(4) poisoning. Group A hosts were untreated. To obtain daily liver function tests (LFTs) and histological samples, on each day up to 8 days we sacrificed four rats in each group. RESULTS: The laboratory examinations showed notable alteration of LFTs in group A, while group B revealed only slight changes. The histological examination showed greater liver damage in group A compared with group B. CONCLUSION: Our results suggest that administration of exogenous VEGF protects the liver from CCl(4)-induced acute hepatic failure. Further studies are underway to assess whether exogenous VEGF is effective in other liver injuries.
Assuntos
Intoxicação por Tetracloreto de Carbono/terapia , Falência Hepática/induzido quimicamente , Falência Hepática/prevenção & controle , Regeneração Hepática/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/uso terapêutico , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Modelos Animais de Doenças , Testes de Função Hepática , Ratos , Ratos Sprague-DawleyRESUMO
The clinical features and course of cardiac involvement in a patient with maternally inherited diabetes and deafness associated with the mitochondrial DNA 3243 mutation are reported. A 45-year-old woman with maternally transmitted diabetes mellitus and deafness presented with congestive heart failure. The patient showed a short P-R interval on electrocardiogram (ECG) and had developed progression from left ventricular hypertrophy to a hypokinetic cardiomyopathy pattern over the course of 10 months. Rapid cardiac change was accompanied by left ventricular remodeling, as shown by wall thinning on echocardiogram and decrease in QRS voltages on ECG. Coronary arteriography revealed no significant stenosis. In the endomyocardial biopsy specimens, light microscopy showed nonspecific cardiomyopathic changes. Genetic testing for mitochondrial DNA mutations in peripheral blood lymphocytes revealed an adenine (A)-to-guanine (G) substitution at nucleotide 3243 in the mitochondrial DNA encoding the transfer RNA for leucine (tRNA Leu (UUR)). The proportion of mutant mitochondrial DNA was 25%. Two of the patient's daughters, aged 13 and 21 years, who were symptom free, were found to carry the same point mutation. A short P-R interval on ECG in the younger of them was the sole manifestation of the mutation. Unfortunately, 6 months after diagnosis, the patient died suddenly at home. Accelerated cardiomyopathy can occur as a mitochondria-related complication in patients with maternally inherited diabetes and deafness associated with the 3243 mutation.
Assuntos
DNA Mitocondrial/genética , Surdez/genética , Diabetes Mellitus/genética , Insuficiência Cardíaca/genética , Mutação Puntual , RNA de Transferência de Leucina/genética , Adolescente , Adulto , Surdez/complicações , Ecocardiografia , Eletrocardiografia , Evolução Fatal , Feminino , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Linhagem , Mutação Puntual/genética , Polimorfismo de Fragmento de RestriçãoRESUMO
Vascular Endothelial Growth Factor (VEGF) is an endothelial cell mitogen and an important stimulator of sinusoidal endothelial cell proliferation. The aim of this research was to study the effects of exogenous VEGF in a rat model of acute liver failure. The study was conducted on 64 rats (240-300 g). All rats underwent intraperitoneal injection (5 ml/kg) of 25% carbon tetrachloride (CCl4) and 75% paraffin oil. This dosage of CCl4 was devised to induce nonfatal acute liver failure with spontaneous recovery in 7 days. The animals were randomly divided into 2 groups. Group B animals underwent i.v. injection of 200 ng of VEGF165 one hour following intra-peritoneal injection of CCl4. To obtain daily liver functional tests (LFTS) and histological liver samples, 4 rats in each group were sacrificed daily up to 8 days. In group A, the liver histology showed massive periportal hepatocyte necrosis associated with portal lymphocytic infiltrates. The peak of the damage was documented at 72 hours following CCl4. Group B showed minimal necrosis, moderate periportal edema and a minimum periportal steatosis. At 48 hours steatotic changes had disappeared and the periportal edema was resolving. LFTs demonstrated severe liver damage in rats in group A. In group A the peak AST (mean 322.5 IU/L) and ALT (mean 250.25 IU/L) were recorded at 72 hours. In group B, at 72 hours the mean AST was 137 IU/L (normal < 95 IU/L) and ALT 68 IU/L(normal < 45 IU/L). The maximum levels of AST and ALT, in group B, were 152.3 IU/L and 72.3 IU/L, at 24 hours. According to our results exogenous VEGF successfully protects the liver from CCl4 induced acute liver failure. Further studies will demonstrate if exogenous VEGF can be effective in other liver injuries.
Assuntos
Falência Hepática Aguda/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular/uso terapêutico , Animais , Ratos , Ratos Sprague-DawleyRESUMO
The first neonatal case of a hemangioma of the diaphragm in a neonate is reported. After 25 months the patient is well with no signs of recurrence. Diaphragmatic tumors should be considered in the differential diagnosis of neonatal thoracic masses.
Assuntos
Diafragma , Hemangioma/cirurgia , Neoplasias Musculares/cirurgia , Feminino , Seguimentos , Hemangioma/diagnóstico por imagem , Humanos , Recém-Nascido , Neoplasias Musculares/diagnóstico por imagem , Procedimentos Cirúrgicos Operatórios/métodos , Toracotomia/métodos , Resultado do Tratamento , UltrassonografiaRESUMO
OBJECTIVE: To evaluate the expression of alpha6 and beta4 integrin subunits on surface and glandular endometrium throughout the menstrual cycle and during early pregnancy. SETTING: Second Department of Obstetrics and Gynecology, University of Catania, Catania, Italy. PATIENT(S): Thirty-two women. Nineteen of the women regularly menstruated in different phases of the cycle, and 13 were in the sixth to ninth week of gestation and required voluntary abortion. INTERVENTION(S): Endometrial specimens collected during endometrial biopsy, hysterectomy, or voluntary abortion. MAIN OUTCOME MEASURE(S): Immunohistochemical staining for alpha6 and beta4 integrin subunits in endometrial tissues. RESULT(S): Both subunits (poorly expressed in preimplantation days) reached a significant peak on the endometrial surface during the implantation window, which tended to disappear in the postimplantation phase. On glandular endometrium they exhibited an opposite trend, showing high levels in the preimplantation and postimplantation days, whereas their expression decreased during the implantation window. The two subunits tended to disappear in early pregnancy. CONCLUSION(S): alpha6 and beta4 integrin subunits are uniformly distributed and highly expressed on the endometrial surface during the implantation window; they decreased dramatically in the postimplantation phase. These results could suggest involvement of integrin-extracellular matrix components in blastocyst-endometrium interaction during the early stages of implantation.
Assuntos
Antígenos CD/metabolismo , Endométrio/metabolismo , Ciclo Menstrual/metabolismo , Gravidez/metabolismo , Adulto , Desenvolvimento Embrionário/fisiologia , Feminino , Humanos , Imuno-Histoquímica/métodos , Integrina alfa6 , Integrina beta4 , Pessoa de Meia-Idade , Primeiro Trimestre da Gravidez , Coloração e Rotulagem , Distribuição TecidualRESUMO
BACKGROUND: Little is known about the causes of death of heart transplant recipients who survive long-term. METHODS: The pathologic and clinical records of 97 patients who underwent heart transplantation in Italy from 1985 to 1995 and died (85 of 97) or underwent retransplantation (12 of 97) at least 2 years after transplantation were surveyed. Graft failures were classified as late (occurring between 2 and 5 years after transplantation) and belated (more than 5 years). RESULTS: Graft vasculopathy was the single most common cause of death (40.0%) and the only cause of late retransplantation. Tumors ranked second (23.5% of deaths), but the expected non-Hodgkin's lymphomas and Kaposi's sarcoma were accompanied by a high number of lung cancers (especially metastasizing adenocarcinomas). They were followed by the emergence or recurrence of pretransplantation diseases (9.4%), fatal infections (exclusively bacterial) (4.7%), the development of transmissible diseases (viral hepatitis and acquired immunodeficiency syndrome, 4.7%), and late acute rejection (2.3%). The distribution of failures differed in the late and belated periods: death and organ loss proportions for graft vasculopathy, respectively, fell and rose from the late to the belated period; some types of malignancy and fatal acute rejection were never observed in the belated period, whereas the emergence of pretransplantation diseases prevailed in the belated period. Graft vasculopathy was more frequent and tumors were less frequent among patients undergoing transplantation for ischemic heart disease. CONCLUSIONS: The reasons why heart transplant recipients die or undergo retransplantation, respectively, in the late and belated periods slightly differ from one another and are widely different than in short-term survivors.
Assuntos
Transplante de Coração , Infecções Bacterianas/mortalidade , Causas de Morte , Rejeição de Enxerto , Humanos , Neoplasias Pulmonares/mortalidade , Linfoma não Hodgkin/mortalidade , Isquemia Miocárdica/cirurgia , Complicações Pós-Operatórias , Reoperação , Sarcoma de Kaposi/mortalidade , Fatores de Tempo , Resultado do Tratamento , Doenças Vasculares/mortalidadeRESUMO
Right ventricle endomyocardial biopsies were obtained from 13 thalassemic patients. Clinical profiles were investigated, and serum ferritin tests were assessed using diagnostic kits. Histochemical iron detection (Perls method) and immunohistochemical stain for ferritin were performed in the endomyocardial samples. Histologic iron overload was observed in eight patients, and variable iron deposits were recognized by a semiquantitative method. There was a statistically evident correlation between serum ferritin and myocardial iron storage. Marked iron deposition was associated with higher immunohistologic ferritin concentration. Iron-negative tissue samples showed bland immunohistochemical positivity. Myocardial interstitial fibrosis was observed in 12 cases; diffuse perimyocytic or perivascular fibrosis and endocardium thickening were the main histologic patterns identified. One biopsy was characterized by marked fibrolipomatous infiltration. Myocyte hypertrophy, myocytolysis, and severe capillary congestion also were observed.
Assuntos
Colestase Extra-Hepática/etiologia , Linfadenite/complicações , Pré-Escolar , Colestase Extra-Hepática/diagnóstico por imagem , Colestase Extra-Hepática/cirurgia , Feminino , Humanos , Testes de Função Hepática , Excisão de Linfonodo , Linfadenite/diagnóstico por imagem , Linfadenite/cirurgia , Tomografia Computadorizada por Raios XRESUMO
Secondary heart failure induced by organ siderosis is the main cause of death in patients affected by thalassemia major. At present it cannot be predicted whether heart siderosis is correlated with iron overload and little is known about the real cardiac histological pattern of post transfusional hemochromatosis in patients with thalassemia major and intermedia. The study aim was to evaluate cardiac iron overload by non invasive and invasive techniques. Fifteen thalassemic patients were investigated and endomyocardial biopsy performed in ten revealed different grades of endomyocardial iron overload with histochemical positivity. Non invasive techniques are not able to furnish an exact picture of the cardiac hemochromatosis. There was a significant correlation between serum ferritin and myocardial iron grade. Patients with elevated ferritin levels and poor compliance to chelating therapy are at high risk of severe heart hemochromatosis. It was seen that endomyocardial biopsy is a useful tool in studying myocardial iron.
Assuntos
Hemossiderose , Miocárdio/metabolismo , Talassemia/metabolismo , Adulto , Biópsia , Ecocardiografia , Feminino , Coração/fisiopatologia , Humanos , Masculino , Talassemia/diagnóstico por imagem , Talassemia/fisiopatologiaRESUMO
Three uterine leiomyomas with vascular invasion (LWVI), two of which were associated with pulmonary leiomyomatous nodules, and a case of intravenous leiomyomatosis (IVL) invading the vena cava and extending to the right atrium, are described. Despite their histological benignity, these lesions have a strong tendency to metastasize and are closely related to the so-called benign metastasizing leiomyoma (BML). From a clinical point of view, the pulmonary nodules of LWVI are stable or slowly-growing. The IVL was a "worm-like" tumour that presented as a cardiac mass. On the basis of their histological and immunohistological features, a unified histogenetic view of LWVI, IVL and BML of the uterus is proposed. LWVI and BML may be the same pathological entity and microscopic vascular invasion may represent the metastatic mechanism of BML. Alternatively, LWVI may be the initial stage of IVL. In rare instances, IVL may be associated with distant parenchymal (pulmonary) metastases. LWVI seems to be the precursor of both BML and IVL.
Assuntos
Vasos Sanguíneos/patologia , Leiomiomatose/patologia , Neoplasias Uterinas/patologia , Adulto , Idoso , Angiomioma/patologia , Feminino , Átrios do Coração , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Pessoa de Meia-Idade , Miocárdio/patologia , Invasividade Neoplásica , Radiografia Torácica , Veias , Veias Cavas/patologiaRESUMO
We investigated whether thymopentin, a synthetic pentapeptide derivative of thymopoietin, could enhance the protective effect of interleukin-1 alpha when both administered prior to sublethal irradiation in the C57BL/6 mouse. Thymopentin (10 mg/kg/day/7 days) was injected intraperitoneally in groups of C57BL/6 mice. Then, interleukin-1 alpha was administered on day 7. Twenty hr later, all groups were given whole body sublethal irradiation of 750 rad by 60Co elements. In some groups of mice, treatment with thymopentin was continued for 1 week after irradiation. Efficacy of the combination treatment was assessed by evaluation of mortality, as well as by histologic examination of the brain, testis, bone marrow, heart and spleen. The combination of relatively low doses of interleukin-1 alpha (700 U) with thymopentin yielded a survival which was nearly that observed with interleukin-1 alpha (1000 U) given alone (about 100%). The optimal effect was observed in animals treated for 15 days with thymopentin, either in combination or alone. In addition, incidence and severity of histological lesions were also lower in animals with the some treatment schedule. Our results suggest that the combined treatment thymopentin-interleukin-1 alpha prevents radiation damage in the mouse.
Assuntos
Interleucina-1/farmacologia , Lesões Experimentais por Radiação/prevenção & controle , Protetores contra Radiação/farmacologia , Timopentina/farmacologia , Animais , Medula Óssea/efeitos dos fármacos , Medula Óssea/patologia , Medula Óssea/efeitos da radiação , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Encéfalo/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Lesões Experimentais por Radiação/mortalidade , Lesões Experimentais por Radiação/patologia , Proteínas Recombinantes/farmacologia , Testículo/efeitos dos fármacos , Testículo/patologia , Testículo/efeitos da radiação , Irradiação Corporal TotalRESUMO
This mortality study deals with the 1068 heart transplants (1054 patients) performed in Italian Units from November 1985 to April 1992. The death rate was 19.7% and the actuarial survival was 89% at 1 month, 83% at 1 year and 74% at 6.5 years. Recipients who died had been less often transplanted for dilated cardiomyopathy, were older (44.1 vs. 41.7 years) and more often male (84.5 vs. 72.7%). Analysis of the causes of death was restricted to orthotopic transplantations (1029/1068 procedures, 195/208 deaths). Deaths were grouped within four intervals: peri-operative (< or = 1 month, 50.0% of deaths), early (> 1 month < or = 3 months, 17.2%), intermediate (> 3 months < or = 2 years, 22.6%) and late (> 2 years, 10.2%). The prime causes of death were mostly postoperative graft failure (whose effects brought about 64% of peri-operative deaths, 28% of early and 7% of intermediate deaths), post-operative complications (10% of peri-operative deaths), acute rejection (10% of total deaths, distributed in all the periods), graft arteriopathy (6% of early, 36% of intermediate and 58% of late deaths), infections (17% of deaths, occurring in all periods but late) and malignant tumours (7% of deaths), lymphomas being the first to occur and Kaposi's sarcoma occurring only in the intermediate period. Repeat transplantation had a poor outcome (death rate 71.4%), two-thirds of the re-transplanted patients' deaths being due to early graft failure and a third to late relapsing graft vasculopathy.
Assuntos
Transplante de Coração/mortalidade , Adulto , Feminino , Oclusão de Enxerto Vascular/mortalidade , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
All the transplantation units within the Italian Heart Transplantation Project are supported by a section of pathology, devoted to the study of the recipient's heart, to patient monitoring by means of a schedule of endomyocardial biopsies, and, if that was the case, to examine the donor's heart and to analyse the causes of death. When successes and failures of the first five years of the Project's activity are weighed up, good results are observed: of the 847 operations performed (orthotopic, heterotopic and heart-lung transplants, and re-transplants) an actuarial survival rate of 77% at 5 years has been achieved. The sections of pathology believe to have contributed significantly to these results, examining as many as 10,446 endomyocardial biopsies. The indications for transplantation were: dilated cardiomyopathy (48.5%); ischemic (35.3%); valvular (5.9%) and congenital (2.4%) heart disease; hypertrophic cardiomyopathy (2.2%); endocardial fibroelastosis (1.7%); restrictive cardiomyopathy (1.4%); anthracycline cardiotoxicity (0.8%); myocarditis (0.8%); cardiac tumours (0.5%) and arrhythmogenic cardiomyopathy (0.2%). Distribution of recipients by sex and age varied according to the indications for transplantation: males were more common among the patients transplanted for ischemic (97%) and valvular (84%) heart disease, as well as for dilated (82%) and hypertrophic (78%) cardiomyopathy, whereas the opposite was true for endocardial fibroelastosis (males constituting 21%) and cardiac tumours (25%). Mean age at transplantation ranged from 49 years (ischemic heart disease) to 6 years (endocardial fibroelastosis). In the follow-up period, a 17.5% death rate was recorded; the main causes of death were the early failure of the transplanted heart (27 pts), postoperative complications (16), hyperacute rejection (4), acute rejection (18), infections (the singular most frequent cause of death, 35 pts), the proliferative endoarteritis of coronary branches (the so-called chronic rejection, that caused 21 deaths and required 14 re-transplants) and the development of neoplasms (11). The actuarial survival curve drops to 89% after the first postoperative month, abates to 82% at the end of the first year, and progressively decreases to 77% at the end of the fifth follow-up year. Rejection monitoring required an average number of 12.5 endomyocardial biopsies per recipient, and allowed 1.7 rejection episodes per patient to be diagnosed. The fewer were the rejection episodes occurring in a unit, the higher was the percentage of deaths due to infections.(ABSTRACT TRUNCATED AT 400 WORDS)
Assuntos
Institutos de Cardiologia , Transplante de Coração , Serviço Hospitalar de Patologia , Fatores Etários , Biópsia , Institutos de Cardiologia/estatística & dados numéricos , Cardiomiopatias/epidemiologia , Cardiomiopatias/mortalidade , Cardiomiopatias/patologia , Cardiomiopatias/cirurgia , Causas de Morte , Feminino , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/mortalidade , Rejeição de Enxerto/patologia , Transplante de Coração/estatística & dados numéricos , Hospitais Universitários/estatística & dados numéricos , Humanos , Itália/epidemiologia , Masculino , Miocárdio/patologia , Serviço Hospitalar de Patologia/estatística & dados numéricos , Fatores SexuaisRESUMO
The development of the thymus and the hypothalamic-pituitary-gonadal axis are linked by bidirectional hormonally mediated relationships. In the present study, the direct involvement of the neuropeptide LHRH in the maturation of the thymus and development of the cell-mediated and humoral immune responses were assessed after treatment of neonatal (from post-natal day 1-day 5) female rats with a potent LHRH-antagonist (LHRH-anta, p-Glu-D-Phe 2.6,Pro3-LHRH, 50 micrograms/rat), and the effects compared to those resulting from neonatal castration. Whereas in control animals the maturation of mitogenic potential in thymocyte cultures showed a progressive and age-dependent increase, reaching a maximal activity at 30 days of age and then decreasing after puberty onset, in LHRH-anta-treated rats, the thymocyte's proliferative response was completely blocked at 7 days of age and remained very low at each time interval studied, until 3 months of age. A similar effect of the LHRH-anta treatment on splenocyte cultures was measured. Moreover, a reduced percentage of the T-helper lymphocyte subpopulation followed LHRH-anta administration. By contrast, in neonatally castrated rats, blastogenic activity was significantly higher, compared to control cultures, at each stage studied. Treatment with LHRH-anta produced a significant decrease in thymus wt, an alteration of the maturational pattern characterized by a cellular monomorphism, reduced thymocyte volume, reduction of the cortical area, and depauperation of the epithelial microenvironment. Moreover, a morphometric analysis revealed a selective decrease in the large lymphoid cell population of the subcapsular cortex at 7 and 15 days. On the other hand, neonatal castration produced an opposite effect, leading to a marked hypertrophy of the cortical area, and counteracted the post-puberal thymus atrophy. When LHRH-anta-treated adult (3-month-old) rats were challenged with an antigenic stimulus (multiple sc injections of complete Freund adjuvant and BSA) and antibody (anti-BSA antibodies of the immunoglobulin G class) production measured in the serum after 15 days, a marked and significant decrease in immunoglobulin G levels was observed, compared to the values measured in untreated control. The described immune deficiencies in LHRH-anta-treated rats were associated with a clear inhibition of sexual maturation. This study clearly indicates that the blockade of central and peripheral LHRH receptors during a critical period for maturation of both hypothalamus-hypophyseal-gonadal axis and brain-thymus-lymphoid axis dramatically impairs immune system development, suggesting a potential role of the neuropeptide LHRH in the bidirectional programming of both neuroendocrine and immune functions.
Assuntos
Animais Recém-Nascidos/fisiologia , Hormônio Liberador de Gonadotropina/metabolismo , Imunidade Celular/fisiologia , Receptores de Superfície Celular/antagonistas & inibidores , Timo/crescimento & desenvolvimento , Animais , Formação de Anticorpos/fisiologia , Feminino , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Hipocampo/metabolismo , Subpopulações de Linfócitos/citologia , Tamanho do Órgão , Ovário/metabolismo , Hipófise/metabolismo , Ratos , Maturidade Sexual , Baço/citologia , Baço/imunologia , Timo/citologia , Timo/metabolismoAssuntos
Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/fisiologia , Linfócitos/imunologia , Glândula Tireoide/crescimento & desenvolvimento , Envelhecimento , Animais , Hormônio Liberador de Gonadotropina/farmacologia , Imunidade Celular/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Ratos , Timo/imunologia , Glândula Tireoide/efeitos dos fármacosRESUMO
The present study was designed to explore the effects of LHRH and its agonists on immune system function. As a first step, to identify a putative site of action, the very potent and stable LHRH agonist (LHRH-A), [D-Ser(TBU6)] des-Gly10-LHRH ethylamide (buserelin), was used as an iodinated ligand to characterize LHRH receptors in a membrane preparation of rat thymus, a key organ of the immune system. The effects of LHRH and LHRH-A were then investigated on the proliferative capacity of rat thymocytes exposed in vitro to a mitogen and on ornithine decarboxylase specific activity. In addition, to determine whether LHRH-A treatment in vivo might directly influence thymic function, we treated hypophysectomized (hypox) rats with a moderately high dose of LHRH-A for a period of 2 weeks, and thymocyte mitogenic capacity, thymus weight, and the histological and functional appearance of the thymus were then assessed. Specific binding of LHRH-A to rat thymic membrane preparations is a saturable process, depending on both time and temperature of incubation, but differs markedly from binding to the rat pituitary or ovarian LHRH receptor in its low binding affinity. Binding is optimal in the absence of chelating agents (EDTA) or divalent metal ions, and increases linearly with increasing protein concentration. Binding is specific for LHRH, LHRH-A, and antagonists. Both the C-terminal amide and N-terminal regions of the LHRH molecule were required for binding, and amino acid substitutions at position 6 markedly enhanced and at position 8 markedly reduced binding potencies in rat thymic tissue. A number of peptides, proteins, and other agents had no effect on the specific binding of LHRH-A to thymic membrane preparations. The binding affinity (Ka) of the membrane receptor of the rat thymus for the LHRH superagonist buserelin was 8.4 x 10(8) M-1, while a higher binding affinity (Ka = 2.8 x 10(9) M-1) was calculated for the ovarian LHRH-binding site. Preincubation of rat thymocytes with LHRH-A for 20 h induced a significant dose-dependent increase in the proliferative response to the mitogen Concanavalin-A, monitored by [3H]thymidine incorporation. Using native LHRH, it was also possible to elicit stimulatory effects on the same parameter, although much higher concentrations were required than with LHRH-A. Furthermore, simultaneous addition of a LHRH antagonist, abolished the LHRH effect on thymocytes. Ornithine decarboxylase specific activity under lectin stimulation was also significantly increased by LHRH-A in cultures of rat thymocytes.(ABSTRACT TRUNCATED AT 400 WORDS)