RESUMO
A 3-month-old infant was examined for inconsolable crying with polydipsia, polyuria, and rapid weight gain. Unexpectedly, the symptoms resolved spontaneously during hospitalization but were aggravated 2 weeks after discharge, with the patient presenting a Cushingoid appearance. Investigations ruled out diabetes mellitus and nephrogenic diabetes insipidus but indicated adrenocortical suppression by exogenous glucocorticoids, which were discovered via toxicologic analysis of her previously compounded omeprazole suspension. After discontinuing the omeprazole suspension, the infant recovered fully and the laboratory results normalized. This case shows us that the assumption of appropriate medication intake may conceal unexpected medication errors. Following this case, the current literature on the benefits and risks of compounding and its impact on patient health is discussed.
Assuntos
Síndrome de Cushing , Diabetes Insípido Nefrogênico , Lactente , Feminino , Humanos , Criança , Glucocorticoides/efeitos adversos , Síndrome de Cushing/induzido quimicamente , Síndrome de Cushing/diagnóstico , Síndrome de Cushing/complicações , Diabetes Insípido Nefrogênico/complicações , Diabetes Insípido Nefrogênico/diagnóstico , Polidipsia/diagnóstico , Doença IatrogênicaRESUMO
BACKGROUND: KBG syndrome is a rare disorder characterized by intellectual disability and associated with macrodontia of the upper central incisors, specific craniofacial findings, short stature and skeletal anomalies. Genetic corroboration of a clinical diagnosis has been possible since 2011, upon identification of heterozygous mutations in or a deletion of the ANKRD11 gene. METHODS: We summarized the height data of 14 adults and 18 children (age range 2-16 years) with a genetically confirmed diagnosis of KBG syndrome. Two of these children were treated with growth hormones. RESULTS: Stature below the 3rd centile or -1.88 standard deviation score (SDS) was observed in 72% of KBG children and in 57% of KBG adults. Height below -2.50 SDS was observed in 62% of KBG children and in 36% of KBG adults. The mean SDS of height in KBG children was -2.56 and in KBG adults -2.17. Two KBG children on growth hormone therapy increased their height by 0.6 and 1 SDS within 1 year, respectively. The former also received a gonadotropin-releasing hormone agonist due to medical necessity. CONCLUSION: Short stature is prevalent in KBG syndrome, and spontaneous catch-up growth beyond childhood appears limited. Growth hormone intervention in short KBG children is perceived as promising.
Assuntos
Doenças do Desenvolvimento Ósseo/complicações , Transtornos do Crescimento/tratamento farmacológico , Hormônio do Crescimento Humano/uso terapêutico , Deficiência Intelectual/complicações , Anormalidades Dentárias/complicações , Anormalidades Múltiplas , Criança , Fácies , Transtornos do Crescimento/complicações , Humanos , Masculino , Resultado do TratamentoRESUMO
UNLABELLED: We aimed to investigate care processes and outcomes among children and adolescents with type 1 diabetes treated in hospital-based multidisciplinary paediatric diabetes centres. Our retrospective cross-sectional study among 12 Belgian centres included data from 974 patients with type 1 diabetes, aged 0-18 years. Questionnaires were used to collect data on demographic and clinical characteristics, as well as process of care completion and outcomes of care in 2008. Most patients lived with both biological or adoption parents (77 %) and had at least one parent of Belgian origin (78 %). Nearly all patients (≥95 %) underwent determination of HbA(1c) and BMI. Screening for retinopathy (55 %) and microalbuminuria (73 %) was less frequent, but rates increased with age and diabetes duration. Median HbA(1c) was 61 mmol/mol (7.7 %) [interquartile range 54-68 mmol/mol (7.1-8.4 %)] and increased with age and insulin dose. HbA(1c) was higher among patients on insulin pump therapy. Median HbA(1c) significantly differed between centres [from 56 mmol/mol (7.3 %) to 66 mmol/mol (8.2 %)]. Incidence of severe hypoglycaemia was 30 per 100 patient-years. Admissions for ketoacidosis had a rate of 3.2 per 100 patient-years. Patients not living with both biological or adoption parents had higher HbA(1c) and more admissions for ketoacidosis. Parents' country of origin was not associated with processes and outcomes of care. CONCLUSION: Outcomes of care ranked well compared to other European countries, while complication screening rates were intermediate. The observed centre variation in HbA(1c) remained unexplained. Outcomes were associated with family structure, highlighting the continuing need for strategies to cope with this emerging challenge.
Assuntos
Atenção à Saúde/normas , Diabetes Mellitus Tipo 1/terapia , Melhoria de Qualidade , Adolescente , Bélgica , Biomarcadores/sangue , Criança , Pré-Escolar , Estudos Transversais , Atenção à Saúde/estatística & dados numéricos , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/complicações , Feminino , Hemoglobinas Glicadas/metabolismo , Pesquisas sobre Atenção à Saúde , Humanos , Hipoglicemiantes/uso terapêutico , Lactente , Recém-Nascido , Modelos Lineares , Masculino , Avaliação de Processos e Resultados em Cuidados de Saúde , Distribuição de Poisson , Estudos Retrospectivos , Inquéritos e QuestionáriosRESUMO
AIMS/HYPOTHESIS: The appearance of autoantibodies (Abs) before diabetes onset has mainly been studied in young children. However, most patients develop type 1 diabetes after the age of 15 years. In first-degree relatives aged under 40 years, we investigated the frequency of seroconversion to (persistent) Ab positivity, progression to diabetes and baseline characteristics of seroconverters according to age. METHODS: Abs against insulin (IAA), glutamate decarboxylase (GADA), insulinoma-associated protein 2 (IA-2A) and zinc transporter 8 (ZnT8A) were measured during follow-up of 7,170 first-degree relatives. RESULTS: We identified 379 (5.3%) relatives with positivity for IAA, GADA, IA-2A and/or ZnT8A (Ab(+)) at first sampling and 224 (3.1%) at a later time point. Most seroconversions occurred after the age of 10 years (63%). During follow-up, Abs persisted more often in relatives initially Ab(+) (76%) than in seroconverters (53%; p < 0.001). In both groups diabetes developed at a similar pace and almost exclusively with Ab persistence (136 of 139 prediabetic individuals). For both groups, progression was more rapid if Abs appeared before the age of 10 years. Baseline characteristics at seroconversion did not vary significantly according to age. CONCLUSIONS/INTERPRETATION: Seroconversion to (persistent) Ab(+) occurs regardless of age. Although the progression rate to diabetes is higher under age 10 years, later seroconverters (up to age 40 years) have similar characteristics when compared with age-matched initially Ab(+) relatives and generate an important minority of prediabetic relatives, warranting their identification and, eventually, enrolment in prevention trials.
Assuntos
Autoanticorpos/química , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/imunologia , Estado Pré-Diabético/imunologia , Adolescente , Adulto , Fatores Etários , Autoanticorpos/imunologia , Proteínas de Transporte de Cátions/química , Proteínas de Transporte de Cátions/imunologia , Criança , Pré-Escolar , Intervalo Livre de Doença , Saúde da Família , Feminino , Glutamato Descarboxilase/química , Glutamato Descarboxilase/imunologia , Humanos , Insulina/química , Insulina/imunologia , Masculino , Fatores de Tempo , Transportador 8 de ZincoRESUMO
AIMS/HYPOTHESIS: Type 1 diabetes arises from an interplay between environmental and genetic factors. The reported seasonality at diagnosis supports the hypothesis that currently unknown external triggers play a role in the onset of the disease. We investigated whether a seasonal pattern is observed at diagnosis in Belgian Type 1 diabetic patients, and if so whether seasonality varies according to age, sex and genetic risk, all known to affect the incidence of Type 1 diabetes. METHODS: The seasonal pattern at clinical diagnosis was assessed in 2176 islet antibody-positive diabetic patients aged 0 to 39 years diagnosed between 1989 and 2000. Additional stratification was performed for age, sex and HLA-DQ genotype. RESULTS: Overall, a significant seasonal pattern at clinical diagnosis of diabetes was observed (p<0.001). More subjects were diagnosed in the period of November to February (n=829) than during the period of June to September (n=619) characterised by higher averages of maximal daily temperature and daily hours of sunshine. However, the seasonal pattern was restricted to patients diagnosed above the age of 10 (0-9 years: p=0.398; 10-19 years: p<0.001; 20-29 years: p=0.003; 30-39 years: p=0.015). Since older age at diagnosis is associated with a male to female excess and a lower prevalence of the genetic accelerator HLA-DQ2/DQ8, we further stratified the patients aged 10 to 39 years (n=1675) according to HLA-DQ genotype and sex, and we found that the seasonal pattern was largely restricted to male subjects lacking DQ2/DQ8 (n=748; p<0.00 vs all others: n=927; p=0.031). CONCLUSIONS/INTERPRETATION: In a subgroup of male patients diagnosed over the age of 10, the later stages of the subclinical disease process may be more driven by sex- and season-dependent external factors than in younger, female and genetically more susceptible subjects. These factors may explain the male to female excess in diabetes diagnosed in early adulthood.
Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Antígenos HLA-DQ/genética , Adolescente , Adulto , Idade de Início , Autoanticorpos/análise , Bélgica/epidemiologia , Criança , Diabetes Mellitus Tipo 1/epidemiologia , Feminino , Marcadores Genéticos , Genótipo , Antígenos HLA-DQ/imunologia , Antígenos HLA-DQ/fisiologia , Humanos , Masculino , Estudos Prospectivos , Sistema de Registros , Estações do Ano , Caracteres SexuaisRESUMO
UNLABELLED: The medical literature on early childhood masturbation is sparse. Only 12 patients who presented with infantile self-stimulation under the age of 1 y are described. During the last 2 y, five girls under 1 y of age presented at our department with self-stimulating behaviour. The diagnosis of this behaviour was difficult, but could be made by watching a video of the attacks. Infantile self-stimulation is often misdiagnosed and unnecessary investigations and useless treatments are often prescribed. Video recording can be of great help to put forward the correct diagnosis. Masturbation is not so uncommon and treatment consists mostly in reassuring the parents. It can, however, be associated with behavioural problems. Few data are available on the clinical outcome of childhood masturbation, but most children seem to develop normally. CONCLUSION: Infantile self-stimulation should always be considered in the differential diagnosis of "strange episodes or attacks".
Assuntos
Masturbação/diagnóstico , Autoestimulação , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Masculino , Gravação em VídeoRESUMO
Inhalation steroid therapy can cause ocular hypertension or open angle glaucoma. The authors describe the case of a young girl who presented with raised intraocular pressure and headaches due to the prolonged administration of nasal and inhalation steroids. The ophthalmologist should monitor the intraocular pressure in patients who use inhalation or nasal steroid therapy on a regular base. The physician or paediatrician should be aware of this complication in children with headaches or diminished visual acuity.
Assuntos
Budesonida/efeitos adversos , Pressão Intraocular/efeitos dos fármacos , Hipertensão Ocular/induzido quimicamente , Administração por Inalação , Asma/tratamento farmacológico , Budesonida/administração & dosagem , Criança , Feminino , Cefaleia/induzido quimicamente , HumanosAssuntos
Neoplasias Cerebelares/terapia , Meduloblastoma/terapia , Segunda Neoplasia Primária/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Terapia Combinada , Diagnóstico Diferencial , Humanos , Masculino , Segunda Neoplasia Primária/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológicoRESUMO
AIMS/HYPOTHESIS: The streptococcal wall component, OK432, prevents diabetes in NOD mice and BB rats by elimination of effector cells. Based on the knowledge of a link between autoimmunity and resistance of immune cells to elimination by apoptosis, we investigated whether OK432 treatment restored the sensitivity of NOD lymphocytes to apoptotic signals centrally (thymus) or peripherally (spleen) or both and we examined the pathways for the enhanced apoptosis rate. METHODS: We treated NOD mice with OK432 (0.1 mg/kg i.p. weekly from 21 to 70 days). Apoptosis was measured by TUNEL 16 h after cyclophosphamide (70 mg/kg) and 24 h after dexamethasone (0.2 mg/mouse). Real time quantitative RT-PCR was used to investigate changes in gene expression. RESULTS: Thymocyte apoptosis levels after cyclophosphamide were restored by OK432 treatment to levels observed in C57BL/6 mice: in NOD males apoptosis increased from 8 +/- 1% to 18 +/- 5% (p < 0.05) compared with 20 +/- 4% in C57BL/6 males, and in NOD females from 6+/- 2% to 11 +/- 2% (p < 0.05) compared with 12 +/- 2% in C57BL/6 females. The dexamethasone-induced thymocyte apoptosis rate was equally restored by OK432 treatment (58 +/- 4% vs 41 +/- 3% in control males (p < 0.0005) and 39 +/- 5% vs 26 +/- 3% in control females (p < 0.05)]. No change in apoptosis levels was on the contrary observed in splenocytes after OK432 treatment. By RT-PCR analysis of a panel of apoptosis-related genes in thymocytes we showed a down-regulation of anti-apoptotic Bcl-xL and c-myc by OK432 treatment. CONCLUSIONS/INTERPRETATION: Our data suggest that OK432 prevents diabetes in NOD mice by better elimination of effector cells through increased sensitivity to apoptotic signals centrally in the thymus.
Assuntos
Apoptose , Diabetes Mellitus Tipo 1/imunologia , Picibanil/farmacologia , Linfócitos T/citologia , Linfócitos T/imunologia , Animais , Apoptose/efeitos dos fármacos , Ciclofosfamida/farmacologia , Dexametasona/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , Imunossupressores/farmacologia , Marcação In Situ das Extremidades Cortadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-myc/genética , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T/química , Timo/química , Timo/citologia , Proteína bcl-XRESUMO
Prevention of type 1 diabetes in NOD mice by 1,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3] is accompanied by a T-helper (Th) 1/Th2 cytokine shift in the pancreas. The aim of this study was to investigate whether this immune shift also occurs outside of the pancreas and whether it is limited to autoantigen-specific immune responses. NOD mice treated with 1alpha,25(OH)2D3 (5 microg/kg every 2 days) or control vehicle were immunized with GAD65 (p524-543) or ovalbumin (OVA) in the rear footpads. First, we examined T-cell proliferation and cytokine production (via enzyme-linked immunosorbent assay) of draining lymph node cells in vitro with or without peptide rechallenge. Although no differences in proliferation were measured between control and 1alpha,25(OH)2D3-treated mice after in vitro GAD65 rechallenge, a marked shift in cytokine secretion profile was seen in 1alpha,25(OH)2D3-treated mice: interleukin-4 was increased (37 +/- 5 vs. 21 +/- 12 pg/ml in controls, P < 0.005), whereas gamma-interferon levels were decreased (6 +/- 3 vs. 9 +/- 3 ng/ml in controls, P < 0.05). This shift was absent in OVA-primed mice. Second, we measured cytokine profiles by reverse transcriptase-polymerase chain reaction in popliteal lymph nodes at different time points after priming with GAD65 or OVA in vivo. A marked Th1/Th2 shift occurred in 1alpha,25(OH)2D3-treated mice after in vivo priming with GAD65. Again, this shift was absent after OVA immunization. Finally, we measured cytokine profiles after rechallenge with a panel of autoantigens (GAD65, heat shock protein 65, insulin B-chain) and control antigens (OVA, keyhole limpet hemocyanine, myelin proteolipid protein, tetanus toxin) and confirmed the Th1/Th2 shift in autoantigen-injected mice but not in control antigen-injected mice. In conclusion, the immune deviation induced by 1alpha,25(OH)2D3 in NOD mice can also be induced in the peripheral immune system but is limited to pancreatic autoantigens.
Assuntos
Autoantígenos/imunologia , Proteínas de Bactérias , Calcitriol/farmacologia , Citocinas/genética , Glutamato Descarboxilase/imunologia , Isoenzimas/imunologia , Ativação Linfocitária , Fragmentos de Peptídeos/imunologia , Células Th1/imunologia , Células Th2/imunologia , Sequência de Aminoácidos , Animais , Autoantígenos/química , Chaperonina 60 , Chaperoninas/imunologia , Diabetes Mellitus Tipo 1/imunologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glutamato Descarboxilase/química , Insulina/imunologia , Interferon gama/genética , Interleucina-4/genética , Isoenzimas/química , Linfonodos/imunologia , Camundongos , Camundongos Endogâmicos NOD , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Células Th1/efeitos dos fármacos , Células Th2/efeitos dos fármacos , Transcrição GênicaRESUMO
Studies on the pathogenesis of type 1 diabetes in humans as well as in the animal models available for the disease have yielded tests allowing for the prediction of type 1 diabetes in first degree relatives of patients affected by the disease. These tests involve analysis of MHC phenotype and screening for the presence of antibodies against the insulin producing beta cell of the pancreas. The screening of first degree relatives for their risk of the disease is coordinated in Belgium by a national registry, the Belgian Diabetes Registry. Animal research and epidemiological studies in humans have moreover suggested strategies that might be effective in preventing type 1 diabetes in persons at risk. Some strategies have an acceptable safety margin and can be tested in humans. At present several large scale clinical trials are being performed worldwide. Results of these trials can be expected in a few years.
Assuntos
Diabetes Mellitus Tipo 1/etiologia , Diabetes Mellitus Tipo 1/prevenção & controle , Ilhotas Pancreáticas/imunologia , Prevenção Primária , Animais , Anticorpos/sangue , Biomarcadores , Bases de Dados Factuais , Marcadores Genéticos , HumanosRESUMO
In this study we have tried to detect abnormalities in the immunophenotype and/or function of dendritic cells from the non-obese diabetic mouse (NOD DC), that might be related to islet autoimmunity. The immunophenotype of NOD splenic DC did not show significant abnormalities as compared with the immunophenotype of splenic DC from C57BL/10 mice. Furthermore, NOD splenic and lymph node DC stimulated proliferation of syngeneic T cells as efficiently as DC from C57BL/10 and BALB/c mice. The allogeneic response induced by NOD DC was similar to or only slightly lower than the response induced by C57BL/10 DC. Both a normal immunophenotype of NOD DC and efficient T cell stimulation were observed regardless of the stage of diabetes development. However, the syngeneic T cell proliferation induced by NOD splenic DC, but not by C57BL/10 splenic DC, was significantly prolonged, and it was accompanied by an increased proportion of activated/memory CD4(+)cells. We demonstrated that during the interaction of NOD cells fewer apoptotic cells were generated as compared with the interaction of C57BL/10 cells. Thus, the prolonged T cell response during the syngeneic interaction between NOD DC and T cells might be due to an impaired apoptosis induction. The impaired apoptosis might be of critical importance in the development of islet autoimmunity in the NOD mouse.
Assuntos
Apoptose/imunologia , Células Dendríticas/imunologia , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 1/imunologia , Linfócitos T/imunologia , Animais , Relação CD4-CD8 , Linfócitos T CD4-Positivos/imunologia , Divisão Celular , Células Cultivadas , Células Dendríticas/citologia , Memória Imunológica , Imunofenotipagem , Antígenos Comuns de Leucócito/imunologia , Ativação Linfocitária , Teste de Cultura Mista de Linfócitos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Baço/citologiaRESUMO
The development of type 1 diabetes in animal models is T cell and macrophage dependent. Islet inflammation begins as peripheral benign Th2 type insulitis and progresses to destructive Th1 type insulitis, which is driven by the innate immune system via secretion of IL-12 and IL-18. We now report that daily application of IL-18 to diabetes-prone female nonobese diabetic mice, starting at 10 wk of age, suppresses diabetes development (p < 0.001, 65% in sham-treated animals vs 33% in IL-18-treated animals by 140 days of age). In IL-18-treated animals, we detected significantly lower intraislet infiltration (p < 0.05) and concomitantly an impaired progression from Th2 insulitis to Th1-dependent insulitis, as evidenced from IFN-gamma and IL-10 mRNA levels in tissue. The deficient progression was probably due to lesser mRNA expression of the Th1 driving cytokines IL-12 and IL-18 by the innate immune system (p < 0.05). Furthermore, the mRNA expression of inducible NO synthase, a marker of destructive insulitis, was also not up-regulated in the IL-18-treated group. IL-18 did not exert its effect at the levels of islet cells. Cultivation of islets with IL-18 affected NO production or mitochondrial activity and did not protect from the toxicity mediated by IL-1beta, TNF-alpha, and IFN-gamma. In conclusion, we show for the first time that administration of IL-18, a mediator of the innate immune system, suppresses autoimmune diabetes in nonobese diabetic mice by targeting the Th1/Th2 balance of inflammatory immune reactivity in the pancreas.
Assuntos
Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/prevenção & controle , Hipoglicemiantes/imunologia , Interleucina-18/fisiologia , Ilhotas Pancreáticas/patologia , Células Th1/imunologia , Animais , Citocinas/biossíntese , Citocinas/genética , Diabetes Mellitus Tipo 1/enzimologia , Diabetes Mellitus Tipo 1/patologia , Feminino , Hipoglicemiantes/administração & dosagem , Injeções , Interleucina-18/administração & dosagem , Interleucina-18/biossíntese , Interleucina-18/genética , Ilhotas Pancreáticas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo II , Estado Pré-Diabético/imunologia , Estado Pré-Diabético/patologia , RNA Mensageiro/biossíntese , Células Th1/enzimologiaAssuntos
DNA Mitocondrial/genética , Diabetes Mellitus Tipo 2/genética , Recém-Nascido de Baixo Peso , Peso ao Nascer/genética , Estudos de Coortes , Feminino , Variação Genética , Genótipo , Humanos , Recém-Nascido , Insulina/genética , Resistência à Insulina/genética , Masculino , Repetições Minissatélites , GravidezRESUMO
The activated form of vitamin D3, 1 alpha,25(OH)2D3, not only plays a central role in bone and calcium metabolism, but also has potent antiproliferative and prodifferentiating effects. Moreover, the combined presence of 25(OH)D3-1 alpha-hydroxylase, as well as the vitamin D receptor in several tissues introduced the idea of a paracrine role for 1 alpha,25(OH)2D3. By introducing chemical modifications into the flexible molecule 1 alpha,25(OH)2D3, a whole generation of vitamin D analogues was created. Due to a clear dissociation of the antiproliferative and prodifferentiating effects from calcaemic effects, these analogues can be used not only for the treatment of bone disorders but also for non-classical applications. In the present review, a summary is given on the use of the 1 alpha,25(OH)2D3 analogues for the treatment of psoriasis, cancer and immune disorders together with new insights in the mechanism of action of these analogues.
Assuntos
Calcitriol/uso terapêutico , Vitamina D/análogos & derivados , Animais , Feminino , Humanos , Sistema Imunitário/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Gravidez , Dermatopatias/tratamento farmacológico , Vitamina D/uso terapêuticoRESUMO
The activated form of vitamin D, 1,25(OH)2D3, and its analogues can prevent type I diabetes in NOD mice. Protection is achieved without signs of systemic immunosuppression and is associated with a restoration of the defective immune regulator system of the NOD mice. The aim of the present study was to investigate whether this restoration of regulator cell function is the only mechanism in the prevention of diabetes by 1,25(OH)2D3. We tested therefore if 1,25(OH)2D3 could prevent cyclophosphamide-induced diabetes, since diabetes occurring after cyclophosphamide injection is believed to be due to an elimination of suppresser cells. NOD mice treated with 1,25(OH)2D3 (5 microg/kg every 2 days) from the time of weaning were clearly protected against diabetes induced by cyclophosphamide (200 mg/kg body wt at 70 days old) (2/12 (17%) versus 36/53 (68%) in control mice, P < 0.005). By co-transfer experiments it was demonstrated that cyclophosphamide had indeed eliminated the suppresser cells present in 1,25(OH)2D3-treated mice. Since cyclophosphamide injection did not break the protection offered by 1,25(OH)2D3, it was clear that diabetogenic effector cells were affected by 1,25(OH)2D3 treatment as well. This was confirmed by the finding that splenocytes from 1,25(OH)2D3-treated mice were less capable of transferring diabetes in young, irradiated NOD mice, and by the demonstration of lower Th1 cytokine levels in the pancreases of 1,25(OH)2D3-treated, cyclophosphamide-injected mice. This better elimination of effector cells in 1,25(OH)2D3-treated mice could be explained by a restoration of the sensitivity to cyclophosphamide-induced apoptosis in both thymocytes and splenocytes, in normally apoptosis-resistant NOD mice. Altogether, these data indicate that the protection against diabetes offered by 1,25(OH)2D3 may be independent of the presence of suppresser cells, and may involve increased apoptosis of Th1 autoimmune effector cells.
Assuntos
Apoptose/efeitos dos fármacos , Calcitriol/farmacologia , Ciclofosfamida/farmacologia , Diabetes Mellitus Tipo 1/prevenção & controle , Imunossupressores/farmacologia , Animais , Citocinas/biossíntese , Citocinas/genética , Linfócitos/efeitos dos fármacos , Linfócitos/fisiologia , Camundongos , Camundongos Endogâmicos NOD , RNA Mensageiro/metabolismoRESUMO
The NOD mouse, a model for type 1 diabetes, is characterized by resistance to apoptosis in immunocytes. The aim of this study was to investigate a link between apoptosis in NOD thymocytes and autoimmunity. First, we demonstrated that the sexual dimorphism in diabetes incidence in NOD mice (females are more diabetes-prone than males) is reflected by differences in apoptosis. Apoptosis in NOD thymocytes, 24 h after dexamethasone, was decreased in both sexes compared with C57B1/6, but it was lower in female mice (26 +/- 2%) than in male mice (50 +/- 3%, P < 0.001). Further, we demonstrated that sex hormones themselves play a central role in this difference, since castration of NOD male mice, which increases diabetes incidence, decreased apoptosis levels (32 +/- 2%), while treatment of NOD female mice with dihydrotestosterone, which protects against diabetes, restored apoptosis to male levels (42 +/- 1.5%). Finally, we demonstrated that 1,25-dihydroxyvitamin D3, a steroid hormone that prevents diabetes in NOD mice, restored apoptosis levels to C57B1/6 reference levels. This improved apoptosis was seen in male (68 +/- 1 vs. 50 +/- 3% in untreated NOD mice, P < 0.001) but especially in female NOD mice (51 +/- 5 vs. 26 +/- 2% in untreated NOD mice, P < 0.001). Fluorescence-activated cell sorter analysis of thymocyte subsets revealed marked differences, especially in CD4+CD8+ and CD4+ cells. We conclude that the sexual dimorphism in diabetes incidence in NOD mice is paralleled by a dimorphism in resistance to apoptotic signals in NOD thymocytes. This resistance to apoptosis is driven by sex hormones and is corrected by 1,25-dihydroxyvitamin D3.
Assuntos
Apoptose/efeitos dos fármacos , Autoimunidade , Calcitriol/farmacologia , Dexametasona/farmacologia , Caracteres Sexuais , Timo/patologia , Animais , Calcitriol/uso terapêutico , Dexametasona/uso terapêutico , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 1/prevenção & controle , Di-Hidrotestosterona/farmacologia , Resistência a Medicamentos , Feminino , Glucocorticoides/farmacologia , Contagem de Linfócitos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Orquiectomia , Timo/imunologiaRESUMO
BACKGROUND: Type 1 diabetes is characterized by the presence of an autoimmune memory, responsible for the destruction of even syngeneic islet grafts. This recurrence of autoimmunity is partly responsible for the need of extensive immunosuppression in pancreas and islet transplantation in type 1 diabetic patients. The aim of the study was to evaluate the capacity of a 20-epi-analog of vitamin D3, KH1060, both alone and in combination with cyclosporine (CsA) to prevent diabetes recurrence in syngeneic islet grafts in nonobese diabetic (NOD) mice. METHODS: Spontaneously diabetic NOD mice grafted with syngeneic islets (n=500) under the kidney capsule were treated with KH1060, CsA, or a combination of both drugs from the day before transplantation until recurrence or 60 days after transplantation. RESULTS: Vehicle-treated mice showed a recurrence of diabetes in 100% of cases (n=17) within 4 weeks. Treatment with high doses of CsA (15 mg/kg/day) or KH1060 (1 microg/kg/2 days) significantly prolonged islet survival (60 days and 50 days, respectively, versus 9.5 days in controls; P<0.001 and P<0.0001). Mice treated with subtherapeutical doses of both drugs combined (KH1060 0.5 microg/kg/2 days + CsA 7.5 mg/kg/day) had significant prolongation of graft survival (48 days; P<0.001) and more importantly, four of five mice that were still normoglycemic 60 days after transplantation showed no recurrence after discontinuation of all treatment. Histology of the grafts of control and combination-treated mice demonstrated that graft infiltration and islet destruction were less severe in grafts of combination-treated mice. Cytokine mRNA analysis in the grafts 6 days after transplantation revealed a clear suppression of interleukin-12 and T helper 1 cytokines and higher levels of interleukin-4 in combination-treated mice. CONCLUSIONS: KH1060, an analog of 1,25(OH)2D3, delays autoimmune disease recurrence after syngeneic islet transplantation in NOD mice, both alone and especially in combination with CsA, possibly restoring tolerance to beta cells in 30% of cases.