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1.
Exp Dermatol ; 21(1): 19-24, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22082249

RESUMO

We assessed the ability of ebselen, a glutathione peroxidase mimic, to reduce pigmentation in various models. In murine B16 melanocytes, 25 µm ebselen inhibited melanogenesis and induced a depolymerisation of actin filaments. In co-cultures of B16 melanocytes with BDVII keratinocytes, a pretreatment of melanocytes with ebselen resulted in a strong inhibition of melanosome transfer to keratinocytes, as shown under optical and electron microscopy. In reconstructed epidermis, topical 0.5% ebselen led to a twofold decrease of melanin without affecting the density of active melanocytes. A similar result was obtained with topical 0.5% ebselen in black guinea pig ears. Ebselen induced a decrease of epidermal melanin parallel to a localisation of melanin and melanosomes in the basal layer. Ebselen appears as a new depigmenting compound that inhibits melanin synthesis and melanosome transfer to keratinocytes.


Assuntos
Antioxidantes/farmacologia , Azóis/farmacologia , Melaninas/biossíntese , Melanossomas/efeitos dos fármacos , Compostos Organosselênicos/farmacologia , Pigmentação da Pele/efeitos dos fármacos , Citoesqueleto de Actina/efeitos dos fármacos , Animais , Linhagem Celular , Sobrevivência Celular , Técnicas de Cocultura , Orelha Externa , Feminino , Cobaias , Humanos , Isoindóis , Queratinócitos/efeitos dos fármacos , Queratinócitos/ultraestrutura , Melanócitos/efeitos dos fármacos , Melanócitos/ultraestrutura , Camundongos , Microscopia Eletrônica , Microtúbulos/efeitos dos fármacos , Monofenol Mono-Oxigenase/metabolismo
2.
Transpl Int ; 25(1): 127-33, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22039919

RESUMO

Hyperhomocysteinemia is seen in patients with decreased bone mineral density. Cyclosporine can cause alveolar bone loss and osteopenia. It is also associated with elevated serum homocysteine levels. We aimed to investigate the effect of cyclosporine on serum homocysteine level, bone volume, and bone density, and determine whether folic acid had a protective effect against bone loss. In an experimental study, 40 male Sprague-Dawley rats were randomly assigned to five groups and received dietary supplementation for 6 weeks with olive oil (Group A), cyclosporine (Group B), folic acid (Group C), and cyclosporine plus folic acid (Group D), or no supplementation (Group F, control). Serum homocysteine, calcium, alkaline phosphatase, total bone volume, periodontal ligament volume, and volume density of bone were compared between groups. Mean serum homocysteine level (10.84 ± 0.93 µmol/l) was significantly higher in group B (cyclosporine supplementation) compared with the other groups (P = 0.001). Mean total mandibular volume was 46.3 ± 13.6 mm(3) in rats treated with cyclosporine, 80.4 ± 15.70 mm(3) in rats treated with folic acid (P = 0.004), and 73.9 ± 21.3 mm(3) in rats treated with cyclosporine plus folic acid (P = 0.028). In our experimental model, cyclosporine increased serum homocysteine levels and decreased bone volume and density. Folic acid may have a preventive role against bone loss in rats treated with cyclosporine.


Assuntos
Ciclosporina/efeitos adversos , Ácido Fólico/farmacologia , Imunossupressores/efeitos adversos , Ração Animal , Animais , Densidade Óssea/efeitos dos fármacos , Ciclosporina/farmacologia , Ácido Fólico/metabolismo , Homocisteína/sangue , Imunossupressores/farmacologia , Masculino , Modelos Biológicos , Modelos Estatísticos , Ratos , Ratos Sprague-Dawley
3.
Reprod Biol Endocrinol ; 3: 31, 2005 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-16083511

RESUMO

BACKGROUND: The effects of ovarian drilling on the serum levels of gonadotropins and androgens have been studied previously. The aim of this study is to evaluate the effects of ovarian drilling on the serum prolactin levels and its relation to ovulation in women with polycystic ovary syndrome. METHODS: This is a prospective controlled study. Thirty-six women with PCOS underwent ovarian electrocauterization in university hospitals. Control group consisted of 35 ovulatory women with unexplained infertility. Hormonal assessment performed in early follicular phase of spontaneous or induced cycle before operation in the two groups and repeated one week after operation. Hormonal assay was also performed in the early follicular phase of the first post-operative menstruation, folliculometry and progesterone assay were also performed in the same cycle. Data were analyzed by "repeated measurement design, discriminant analysis, correlation coefficient, and Fisher exact test". RESULTS: Six to ten weeks after operation the serum mean +/- SD prolactin levels increased from 284.41 +/- 114.32 mIU/ml to 354.06 +/- 204.42 mIU/ml (P = 0.011). The same values for the control group were 277.73 +/- 114.65 to 277.4 +/- 111.4 (P = 0.981) respectively. Approximately 45% of subjects in PCOS group remained anovulatory in spite of decreased level of LH and testosterone. Prolactin level remained elevated in 73.2% of women who did not ovulate 6-10 weeks after the procedure. CONCLUSION: Hyperprolactinemia after ovarian cauterization may be considered as a possible cause of anovulation in women with polycystic ovaries and improved gonadotropin and androgen levels. The cause of hyperprolactinemia is unknown. Hormonal assay particularly PRL in anovulatory patients after ovarian cauterization is recommended.


Assuntos
Anovulação/cirurgia , Eletrocoagulação , Hiperprolactinemia/etiologia , Laparoscopia , Ovário/cirurgia , Síndrome do Ovário Policístico/complicações , Complicações Pós-Operatórias , Adulto , Anovulação/etiologia , Feminino , Humanos , Hiperprolactinemia/diagnóstico , Prolactina/sangue , Estudos Prospectivos
4.
Diabetes Res Clin Pract ; 68(2): 111-6, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15860238

RESUMO

CTLA-4 is a homeostatic regulator of T cell activation and is believed to play a critical role in peripheral tolerance. The contribution of CTLA-4 gene variants to type 1 diabetes has been analyzed in several ethnic groups. In this study, the association of CTLA-4 +49 A/G polymorphism with type 1 diabetes was investigated in Iranian patients. One hundred and nine patients and 331 healthy subjects formed the studied populations. CTLA-4 A/G polymorphism at position 49 in exon 1 was identified using PCR-SSCP and PCR-RFLP methods. Patient numbers with A/G, A/A and G/G genotypes were 78 (71.5%), 21 (19.3%) and 10 (9.2%) while in healthy controls, these were 149 (45%), 146 (44.2%) and 36 (10.8%), respectively. A significant decrease in the frequency of the A/A genotype was observed in the diabetes group (p = 0.000004). In diabetic subjects, the allele frequency of G was also higher than in controls (45% versus 33.4%, p = 0.00269). The differences in the genotypes and the alleles were greater in patients with younger age of diabetes onset (age < or = 15 years) compared with controls (p = 0.000001 and p = 0.000579, respectively). The distribution of the CTLA-4 polymorphism between patients did not show any significant difference according to diabetic ketoacidosis at onset. In conclusion, the result of this study in combination with the previous reports of other ethnic populations showed that CTLA-4 +49 A/G polymorphism confers genetic susceptibility to type 1 diabetes, particularly in younger individuals.


Assuntos
Antígenos de Diferenciação/genética , Diabetes Mellitus Tipo 1/genética , Predisposição Genética para Doença/genética , Adulto , Fatores Etários , Alelos , Antígenos CD , Antígeno CTLA-4 , Doença Crônica , Complicações do Diabetes/genética , Cetoacidose Diabética/genética , Éxons , Feminino , Perfilação da Expressão Gênica/estatística & dados numéricos , Genótipo , Heterozigoto , Homozigoto , Humanos , Irã (Geográfico)/etnologia , Masculino , Polimorfismo Genético
5.
Bone ; 35(3): 760-5, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15336613

RESUMO

Polymorphisms of methylenetetrahydrofolate reductase (MTHFR) have been well documented to cause hyperhomocysteinemia, and recent studies suggest an association of C677T mutation of methylenetetrahydrofolate reductase with low bone mineral density (BMD). In this study, the association of plasma total homocysteine (Hcy), plasma folate, and vitamin B12 as well as methylenetetrahydrofolate reductase C667T polymorphism with bone mineral density at neck of femur and lumbar spine in 271 postmenopausal Iranian women was investigated. Bone mineral density was measured by dual-energy X-ray absorptiometry. Restriction fragment length polymorphism was used for genotyping the methylenetetrahydrofolate reductase polymorphism. Plasma total homocysteine, plasma folate, and vitamin B12 were also determined. The bone mineral densities at the neck of femur and lumbar spine together with other clinical characteristics among methylenetetrahydrofolate reductase genotypes (CC, CT, and TT) were examined. Bone mineral densities at both neck of femur (r = -0.18, P = 0.003) and lumbar spine (r = -0.16, P = 0.01) were significantly and negatively correlated with the logarithm of plasma total homocysteine. Bone mineral density at the lumbar spine was also significantly and positively associated with plasma folate (r = 0.14, P = 0.02). However, no correlation between methylenetetrahydrofolate reductase polymorphism with bone mineral density at neck of femur (r = -0.01, P = 0.81) and lumbar spine (r = -0.04, P = 0.51) was observed. The negative association of plasma total homocysteine with bone mineral density was no longer significant when adjusted for folate and vitamin B12. Plasma folate and age were the main predictors of plasma total homocysteine explaining 15.3% and 5.2% of the variance of plasma total homocysteine, respectively. Methylenetetrahydrofolate reductase polymorphism, however, was not associated with plasma folate (r = 0.086, P = 0.17) or vitamin B12 (r = 0.05, P = 0.4). Plasma folate was one of the main predictors explaining 3.0% and 1.7% of variance of the bone mineral density at femoral neck and lumbar spine, respectively. Results from this study suggest hyperhomocysteinemia as a result of folate deficiency, but not methylenetetrahydrofolate reductase polymorphism, is independently associated with low bone mineral density and may contribute to the pathogenicity of osteoporosis in postmenopausal Iranian women.


Assuntos
Densidade Óssea/genética , Ácido Fólico/sangue , Homocisteína/sangue , Metilenotetra-Hidrofolato Redutase (NADPH2)/sangue , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/genética , Idoso , Análise de Variância , Intervalos de Confiança , Estudos Transversais , Feminino , Humanos , Irã (Geográfico) , Pessoa de Meia-Idade , Polimorfismo Genético/genética , Análise de Regressão , Estatísticas não Paramétricas
6.
Bone ; 46(5): 1344-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19948262

RESUMO

Severe hyperhomocysteinemia, as seen in classic homocystinuria, is associated with several skeletal malformations and osteopenia. Moreover, hyperhomocysteinemia during pregnancy has been associated with multiple developmental defects in the fetus. This study was undertaken to determine whether offspring of hyperhomocysteinemic mothers have demonstrable changes in bone volume and the epiphyseal growth plate. Ten adult female Sprague-Dawley rats were randomly assigned to the control or experimental group. The experimental group received 100 mg/kg/day of homocysteine in their drinking water for 3 weeks before mating and for the total duration of pregnancy. In each group, three pups per mother were randomly selected. The histomorphometric properties of tibial, radial and vertebral growth plates of newborn rats and the volume fraction of bone were compared between groups. The plasma homocysteine concentration at the end of study was significantly higher in dams in the experimental group (16.42+/-1.5 vs. 4.7+/-1.7 mumol/L, P<0.05). In offspring born to dams given the homocysteine supplement, the volume fraction of bone in the tibia (30.7+/-1.5% vs. 36.8+/-1.9%, P<0.05), radius (29.6+/-1.1% vs. 37.4+/-2%, P<0.05) and vertebra (34.4+/-1.8% vs. 41+/-1.9%, P<0.05) were significantly decreased whereas vertical heights of proliferative (423+/-25.1 vs. 301.8+/-28.1 microm for radius and 131.9+/-5.9 vs. 107.8+/-3.5 microm for vertebra) and hypertrophic zones (213.1+/-12 vs. 163.3+/-7.5 microm for tibia, 153.2+/-7.7 vs. 121.1+/-7.9 microm for radius and 112+/-9.9 vs. 88.4+/-10.1 microm for the vertebra) were increased (P<0.05). The results showed that the administration of homocysteine caused osteopenia in newborn rats. In addition, these data suggest that hyperhomocysteinemia may induce disruption of normal development of epiphyseal cartilage in the rat embryo.


Assuntos
Doenças Ósseas Metabólicas/induzido quimicamente , Idade Gestacional , Hiper-Homocisteinemia/fisiopatologia , Osteogênese/fisiologia , Complicações na Gravidez/fisiopatologia , Animais , Animais Recém-Nascidos , Feminino , Lâmina de Crescimento/anatomia & histologia , Lâmina de Crescimento/patologia , Homocisteína/sangue , Homocisteína/toxicidade , Hiper-Homocisteinemia/sangue , Hiper-Homocisteinemia/induzido quimicamente , Masculino , Microscopia , Gravidez , Complicações na Gravidez/sangue , Complicações na Gravidez/induzido quimicamente , Rádio (Anatomia)/anatomia & histologia , Rádio (Anatomia)/patologia , Ratos , Ratos Sprague-Dawley , Coluna Vertebral/anatomia & histologia , Coluna Vertebral/patologia , Tíbia/anatomia & histologia , Tíbia/patologia
7.
Bone ; 44(2): 331-4, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18992857

RESUMO

Lithium salts are widely used in treating psychiatric patients. Lithium may be associated with hyperparathyroidism, a risk factor for osteoporosis. However, the data on the effect of lithium on bone mass are conflicting. We assessed bone mineral density with dual-energy X-ray absorptiometry at the hip and lumbar spine in 75 lithium treated outpatients and 75 normal subjects matched for age, sex and body mass index. Serum total calcium, intact parathyroid hormone (PTH), estradiol, osteocalcin, total alkaline phosphatase (ALP) and C-telopeptide (CTX) in addition to fasting urinary calcium excretion were also determined in both groups. The mean (+/-SD) bone density in lithium treated patients was 4.5% higher at the spine (P<0.05), 5.3% higher at the femoral neck (P<0.05) and 7.5% higher at the trochanter (P<0.05). In addition, lithium treated patients had lower serum total ALP (P<0.005), lower serum osteocalcin (P<0.005) and lower serum CTX (P<0.05) but the total calcium, PTH and urinary calcium excretion did not differ significantly between patients and controls. In conclusion, our results suggest that maintenance therapy with lithium carbonate may preserve or enhance bone mass. These data also suggest a lower bone turnover state in those receiving lithium.


Assuntos
Densidade Óssea/efeitos dos fármacos , Lítio/farmacologia , Adulto , Estudos de Casos e Controles , Demografia , Feminino , Humanos , Masculino
8.
Arch Iran Med ; 12(6): 550-4, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19877746

RESUMO

BACKGROUND: Chronic antiepileptic therapy has been associated with metabolic bone diseases including osteomalacia and osteoporosis. The object of this study was to assess the effect of first line anticonvulsants on bone density and vitamin D levels in Iranian ambulatory patients. METHODS: We conducted a cross-sectional study assessing bone density with dual energy X-ray absorptiometry at the hip and lumbar spine in 90 outpatients receiving anticonvulsants and 90 normal subjects matched for age, sex, and body mass index. Plasma total calcium, intact parathyroid hormone, total alkaline phosphatase in addition to 25 hydroxy vitamin D were also determined in both groups. RESULTS: The mean (+/-SD) bone density in patients treated with antiepileptic drugs was lower at the spine (T Score= -084+/-1.18 vs. -0.5+/-1.18, P< 0.05) and femoral neck (T Score= -0.83+/-1.11 vs. -0.46+/-1.1, P<0.05), compared to the control group of subjects. In addition, serum total alkaline phosphatase was significantly higher in patients (246.5+/-127 vs. 190+/-65.3, P=0.004), but the total calcium, parathyroid hormone and 25 hydroxy vitamin D did not differ significantly between patients and controls. CONCLUSION: Our results suggest that maintenance therapy with antiepileptic drugs may decrease bone mass. These data also suggest a higher bone turnover rate in those receiving anticonvulsants.


Assuntos
Anticonvulsivantes/efeitos adversos , Densidade Óssea/efeitos dos fármacos , Adulto , Fosfatase Alcalina/sangue , Remodelação Óssea/efeitos dos fármacos , Cálcio/sangue , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Vitamina D/análogos & derivados , Vitamina D/sangue
9.
Saudi J Gastroenterol ; 14(3): 135-8, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19568522

RESUMO

BACKGROUND/AIM: This study was performed to evaluate the prevalence of celiac disease (CD) in Shiraz, southern Iran. MATERIALS AND METHODS: Serum samples were collected from 1440 persons (age range = 20-83 years, mean age = 45.4 years) in 2004 and screened for endomysial and tissue transglutaminase antibodies. A questionnaire was completed for all subjects in relation to gastrointestinal (GI) symptoms and cases with positive serology were requested to undergo small-bowel biopsy. RESULTS: Seven cases (0.5%) were positive for IgA anti-tissue transglutaminase (anti-tTG), and only two (0.14%) were positive for IgA anti-endomysial antibody (anti-EMA), both of whom had highly positive anti-tTg levels (40.4 and 48.0 IU/l). The major clinical symptoms of CD, such as recurrent abdominal pain and change in bowel habits were present in all patients with positive anti-tTG assays. Only five subjects with positive serology agreed to undergo upper GI endoscopy and duodenal biopsy. Three of these cases were reported with Marsh I histologic findings, while in the two cases with positive serologic anti-EMA, more advanced forms of CD were present. CONCLUSION: The prevalence of CD in apparently healthy adults was lower than the reported series from northern parts of the country; therefore, we suggest a more long-term follow-up study in high-risk groups, especially in the apparently healthy subjects in our region.

10.
Exp Dermatol ; 15(7): 509-14, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16761959

RESUMO

Monobenzylether of hydroquinone (MBEH) has long been utilized for the depigmentation therapy of patients with extensive vitiligo. In this approach, the normally pigmented areas surrounding vitiligo lesions are depigmented to achieve a uniform skin tone. One of the important disadvantages of MBEH therapy, however, is the resistance of a considerable number of vitiligo patients against the depigmenting effect of this agent. We have previously proposed that the glutathione-dependent cytoprotection of melanocytes can be impaired through the inhibition of the enzyme glutathione S-transferase by retinoic acid (RA). The combination of RA with melanocytotoxic agents could thus lead to increased susceptibility of melanocytes to such compounds. In this study we have shown, for the first time, that the melanocytotoxic and depigmenting effects of MBEH are synergistically enhanced when it is combined with RA. The treatment of black guinea pig skin with RA (0.025%) alone induced no significant changes in the number of epidermal melanocytes and no skin depigmentation. On the other hand, MBEH (10%) produced mild to moderate skin depigmentation and reduced the average number of melanocytes from 76 (+/-5)/field (magnification: x 40) in control sites, to 42 (+/-6)/field in the depigmented skin. The RA (0.025%)-MBEH (10%) combination, however, produced a complete degree of depigmentation in the majority of treated sites after 10 days of application and reduced the average number of melanocytes to only 6 (+/-6)/field. RA-MBEH combination serves as a very potent skin depigmenting formula and now awaits future assessments of its potential use for the treatment of extensive vitiligo.


Assuntos
Hidroquinonas/farmacologia , Melanócitos/efeitos dos fármacos , Pigmentação da Pele/efeitos dos fármacos , Tretinoína/farmacologia , Animais , Fármacos Dermatológicos/farmacologia , Sinergismo Farmacológico , Epiderme/química , Epiderme/efeitos dos fármacos , Epiderme/patologia , Feminino , Cobaias , Cor de Cabelo/efeitos dos fármacos , Melaninas/análise , Melanócitos/patologia
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