RESUMO
Oestradiol (E2) is a critical factor for multiple systems' development during the embryonic period. Here, we aimed to investigate the effects of oestradiol on intrahepatic bile duct development, which may allow a better understanding of congenital bile duct dysplasia. DLK+ hepatoblasts were extracted from the C57BL/6CrSlc foetal mice and randomly divided into control group, oestradiol groups (1, 10, 100 nM) and oestradiol (10 nM) + DAPT (inhibitor of Notch signalling; 40 µM) group for in vitro experiments. For in vivo analysis, pregnant mice were divided into control group, oestradiol (intraperitoneal injection of 0.6 mg/kg/day) ± DAPT (subcutaneous injection of 10 mg/kg/day) groups and tamoxifen (gavage administration of 0.4 mg/kg/day) group. The results showed that oestradiol promoted hepatoblast differentiation into cholangiocytes and intrahepatic bile duct development during the embryonic period. Tamoxifen, an antioestrogenic drug, inhibited the above processes. Moreover, oestradiol promoted the expression of Notch signalling pathway-associated proteins and genes both in vitro and in vivo. Notably, DAPT addition inhibited the oestradiol-mediated effects. In conclusion, oestradiol can promote hepatoblast differentiation into cholangiocytes and intrahepatic bile duct development of C57BL/6CrSlc mice during embryonic period via the Notch signalling pathway.
Assuntos
Ductos Biliares Intra-Hepáticos/embriologia , Ductos Biliares Intra-Hepáticos/metabolismo , Estradiol/metabolismo , Organogênese , Receptores Notch/metabolismo , Transdução de Sinais , Animais , Biomarcadores , Diferenciação Celular , Células Cultivadas , Estradiol/farmacologia , Expressão Gênica , Hepatócitos/metabolismo , Imuno-Histoquímica , Imunofenotipagem , Camundongos , Camundongos Endogâmicos C57BL , Organogênese/efeitos dos fármacos , Células-Tronco/metabolismoRESUMO
OBJECTIVE: To investigate the effect of glutaryl-CoA dehydrogenase (GCDH) gene silencing and accumulation of lysine metabolites on the viability of hepatocytes. METHODS: BRL cells were divided into normal control group, negative control group, and GCDH silencing group. The shRNA lentiviral vector for silencing GCDH gene was constructed, and the BRL hepatocytes in the GCDH silencing group and the negative control group were infected with this lentivirus and negative control virus respectively, and then cultured in a medium containing 5â mmol/L lysine. Immunofluorescence assay was used to measure the infection efficiency of lentivirus. Western blot was used to measure the expression of GCDH protein. MTT assay was used to evaluate cell viability. Hoechest33342 staining was used to measure cell apoptosis. Western blot was used to measure the expression of Caspase-3, an index of cell apoptosis. RESULTS: The lentivirus constructed effectively silenced the GCDH gene in hepatocytes (P<0.01). MTT assay and Hoechest 33342 staining showed no significant differences in cell viability and apoptosis between groups (P>0.05). There was also no significant difference in the expression of Caspase-3 protein between groups (P>0.05). CONCLUSIONS: GCDH gene silencing and accumulation of lysine metabolites may not cause marked hepatocyte injury.
Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/patologia , Encefalopatias Metabólicas/patologia , Glutaril-CoA Desidrogenase/deficiência , Glutaril-CoA Desidrogenase/genética , Hepatócitos/patologia , Lisina/metabolismo , Erros Inatos do Metabolismo dos Aminoácidos/terapia , Animais , Apoptose , Encefalopatias Metabólicas/terapia , Caspase 3/metabolismo , Sobrevivência Celular , Células Cultivadas , Imunofluorescência , Inativação Gênica , RatosRESUMO
BACKGROUND: Suppressor of cytokine signaling-1 and -3 (SOCS-1 and SOCS-3) are two important negative regulators in the insulin-signaling pathway, and their overexpression may aggravate insulin resistance. Subjects with insulin resistance are often obese and have increased expressions of SOCS-1 and SOCS-3. We speculated that SOCS-1 and SOCS-3 may be involved in abnormal deposition of adipose tissues during insulin resistance. METHODS: A catch-up growth intrauterine growth retardation (CG-IUGR) rat model with insulin resistance was established; mRNA and protein expression of SOCS-1, SOCS-3, the CCAAT/enhancer binding protein (C/EBPα), and peroxisome proliferator-activated receptor (PPARγ) in adipose tissue were measured by real-time PCR and western blot; plasmids carrying small hairpin RNAs (shRNAs) targeting the SOCS-1 and SOCS-3 genes were constructed and transfected into preadipocytes, which were then induced to mature. At 72 h after differentiation was induced, the expressions of C/EBPα and PPARγ, two important molecules promoting the differentiation of preadipocytes, were detected. RESULTS: Expressions of SOCS-1, SOCS-3, C/EBPα, and PPARγ were markedly increased in adipose tissues of CG-IUGR rats, whereas the expressions of C/EBPα and PPARγ were significantly reduced after gene silencing of SOCS-1 or SOCS-3 in adipocytes. CONCLUSION: Overexpression of SOCS-1 and SOCS-3 may enhance the expression of C/EBPα and PPARγ, resulting in abnormal deposition of adipose tissues during insulin resistance.
Assuntos
Adipócitos/fisiologia , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Resistência à Insulina/fisiologia , PPAR gama/metabolismo , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Animais , Western Blotting , Diferenciação Celular/fisiologia , Processos de Crescimento Celular/fisiologia , Primers do DNA/genética , Inativação Gênica , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Proteína 1 Supressora da Sinalização de Citocina , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/genéticaRESUMO
BACKGROUND: Recombinant human growth hormone (rhGH) therapy has shown to improve height and body composition in children with Prader-Willi syndrome (PWS), the evidence of early rhGH treatment on motor and mental development is still accumulating. This study explored the time effect on psychomotor development, anthropometric indexes, and safety for infants and young children with PWS. METHODS: A phase 3, single-arm, multicenter, self-controlled study was conducted in six sites. Patients received rhGH at 0.5 mg/m2/day for first four weeks, and 1 mg/m2/day thereafter for up to 52 weeks. Motor development was measured using Peabody Developmental Motor Scales-second edition, mental development using Griffiths Development Scales-Chinese (GDS-C). Height standard deviation score (SDS), body weight SDS, and body mass index (BMI) SDS were also assessed. RESULTS: Thirty-five patients were enrolled totally. Significant improvements were observed in height, body weight, and BMI SDS at week 52; GDS-C score showed significant improvement in general quotient (GQ) and sub-quotients. In a linear regression analysis, total motor quotient (TMQ), gross motor quotient (GMQ), and fine motor quotient were negatively correlated with age; however, treatment may attenuate deterioration of TMQ and GMQ. Changes in GQ and locomotor sub-quotient in < 9-month group were significantly higher than ≥ 9-month group. Mild to moderate severity adverse drug reactions were reported in six patients. CONCLUSION: Fifty-two-week treatment with rhGH improved growth, BMI, mental development, and lessened the deterioration of motor function in infants and young children with PWS. Improved mental development was more pronounced when instituted in patients < 9 months old.
Assuntos
Hormônio do Crescimento Humano , Síndrome de Prader-Willi , Criança , Pré-Escolar , Humanos , Lactente , Antropometria , Índice de Massa Corporal , Peso Corporal , Hormônio do Crescimento Humano/uso terapêutico , Hormônio do Crescimento Humano/efeitos adversos , Síndrome de Prader-Willi/tratamento farmacológico , Proteínas Recombinantes/efeitos adversosRESUMO
OBJECTIVE: To study changes of glycolipid metabolism and adipocyte function in an catch-up growth intrauterine growth retardation (IUGR) rat model. METHODS: IUGR rat model was established by maternal nutrition restriction during pregnancy. Newborn IUGR pups were used as IUGR group, and normal newborn pups were used as control group (appropriate for gestational age, AGA group). At age of 12 weeks, plasma samples were collected for the test of triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), adiponectin and acylation stimulating protein (ASP). Oral glucose tolerance test (OGTT) was performed for the test of glucose and insulin levels, and insulin resistance index (IRI) was calculated. Expression of glucose transfer 4 (GLUT-4) in adipocytes was examined by confocal microscopy. RESULTS: Body weight and BMI in the IUGR group were significantly higher than in the AGA group by 12 weeks (P<0.01), and plasma TC, TG and LDL-C levels in the IUGR group were higher than in the AGA group, but HDL-C was lower (P<0.05). In the OGTT test, blood glucose level and IRI score in the IUGR group were higher than in the AGA group (P<0.05). Compared with the AGA group, the IUGR group had a higher ASP level (P<0.05) and a lower adiponection level (P<0.05). GLUT4 expression in the adipocytes was significantly lower in the IUGR group than in the AGA group (P<0.05). CONCLUSIONS: Catch-up growth may be obviously noted in IUGR rats after birth. Both hyperlipidaemia and insulin resistance occur at age of 12 weeks. Dysfunction of adipocytes decreased expression of GLUT-4 may be risk factors for insulin resistance in IUGR rats.
Assuntos
Adipócitos/fisiologia , Metabolismo dos Carboidratos , Retardo do Crescimento Fetal/fisiopatologia , Metabolismo dos Lipídeos , Animais , Glicemia/análise , Índice de Massa Corporal , Peso Corporal , Feminino , Transportador de Glucose Tipo 4/análise , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND: Perrault syndrome (PRLTS) is a rare autosomal recessive disorder characterized by sensorineural hearing loss in both sexes and ovarian dysfunction in females. In some cases, patients present with a diversity of neurological signs. Six genes are known to cause Perrault syndrome. CASE REPORT: We report an 11-year-old Chinese girl with delayed gonadal development, sensorineural hearing loss, and neurologic manifestations. Genetic etiology was identified by whole-exome sequencing and confirmed via Sanger sequencing. Compound heterozygous variants with one novel variant c.1752C>A (p.D584E) and one known pathogenic variant c.1172G>A (p.R391H) in TWNK were discovered in the child and inherited from her parents, respectively. CONCLUSION: The compound heterozygous variants c.1172G>A (p.R391H) and c.1752C>A (p.D584E) of the TWNK gene probably underlie PRLTS type 5 (PRLTS5). This study expands the mutation spectrum of TWNK pathogenicity in the PRLTS5 phenotype.
RESUMO
OBJECTIVE: This study examined the effects of PI3K inhibitor LY294002 on the differentiation of mouse preadipocytes and the expression of CCAAT enhancer binding protein α (C/EBPα) and peroxisome proliferation activated receptor γ (PPARγ), in order to study the possible roles of insulin receptor substrate (IRSs)/PI3K signal pathway in the differentiation of preadipocytes. METHODS: The mouse 3T3-L1 cells were cultured normally and divided into experimental and control groups. 3T3-L1 cells in the experimental group were treated with PI3K inhibitor LY294002 (25 µmol/L) and those in the control group were treated with DMSO culture medium. 3-isobutyl-1-methylxanthine (IBMX) (0.5 mmol/L), dexamethasone (10-6 mol/L) and insulin (5 µg/mL) were used to induce the differentiation of 3T3-L1 preadipocytes in both groups. Before culture, and 2, 4 and 8 days after culture, the cells were collected to detect the expression of C/EBPα and PPARγ by real-time PCR and Western blot assays. The lipid droplets of 3T3-L1 preadipocytes were observed by oil-red O staining. RESULTS: PI3K inhibitor LY294002 did not affect the expression of C/EBPα and PPARγ in un-induced 3T3-L1 preadipocytes (P>0.05), but decreased the expression of C/EBPα and PPARγ during the in vitro induced differentiation of 3T3-L1 preadipocytes compared with the control group (P<0.05 or 0.01). The lipid droplets count was greatly reduced by LY294002. CONCLUSIONS: PI3K inhibitor LY294002 can inhibit the differentiation of mouse 3T3-LI preadipocytes and the expression of C/EBPα and PPARγ in the differentiation of 3T3-LI preadipoeytes, suggesting that IRSs/PI3K signal pathway may play an important role in the differentiation of 3T3-L1 preadipocytes by regulating the expression of C/EBPα and PPARγ.
Assuntos
Adipócitos/efeitos dos fármacos , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Cromonas/farmacologia , Morfolinas/farmacologia , PPAR gama/genética , Inibidores de Fosfoinositídeo-3 Quinase , Células 3T3-L1 , Adipócitos/citologia , Animais , Proteína alfa Estimuladora de Ligação a CCAAT/análise , Diferenciação Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , PPAR gama/análise , RNA Mensageiro/análiseRESUMO
BACKGROUND: To compare the physical development status, level of blood glucose and lipid metabolism in small for gestational age (SGA) and appropriate for gestational age (AGA) groups with central precocious puberty (CPP). METHODS: This was a retrospective study. Three hundred and twenty-two girls with CPP were divided into the AGA group (304 cases) and the SGA group (18 cases). Physical index such as height, weight, and body mass index (BMI), as well as sex hormones, adrenal androgens, blood lipid levels, fasting blood glucose, insulin levels, and homeostasis model assessment of insulin resistance (HOMA-IR) were compared between the two groups. RESULTS: Height, weight, and BMI in the SGA group were lower than those in the AGA group (P<0.05). The level of LH/FSH, estradiol, testosterone, DHEA and androstenedione had no significant difference between the SGA group and AGA group (P>0.05). The fasting blood glucose, insulin level, HOMA-IR, high-density lipoprotein (HDL) and the average level of triglycerides were similar between these two groups (P>0.05). There was a statistically significant difference in total cholesterol and low-density lipoprotein (LDL) between the two groups (P<0.05). However, the blood lipids and blood glucose in both groups were within the normal range. CONCLUSIONS: The height, weight, BMI, serum cholesterol and LDL of girls in SGA with CPP were significantly lower than that of those girls born AGA.
RESUMO
BACKGROUND: Recombinant human growth hormone (rhGH) was approved for the therapy of pediatric patients with growth hormone deficiency (GHD) by the Food and Drug Administration (FDA) of the United States in 1985. This study aims to evaluate the effects of rhGH therapy on thyroid function in pediatric patients with GHD. METHODS: A total of 55 pediatric patients, who had been diagnosed with GHD and received rhGH therapy for 6-24 months, and who could regularly come to our hospital for outpatient visits from May 1, 2014 to April 30, 2017, were selected for the study. All of the patients were treated for at least six months, among which 44 patients were treated for 12 months, and 32 patients were treated for 18 months, and 16 patients were treated for 24 months. RESULTS: (I) During the course of the rhGH therapy, none of the patients had a free thyroxine (FT4) level lower than the normal lower limit. (II) The FT4 level decreased during the course of the therapy, when compared to the level at baseline, and the difference was statistically significant after 24 months of therapy. In the puberty group, the FT4 level had significantly decreased by the 12th month of therapy, when compared to the baseline, but there was no significant change in the FT4 and thyroid-stimulating hormone (TSH) levels at the remaining observation time points of treatment. CONCLUSIONS: Growth hormone (GH) replacement therapy may affect the metabolism of the thyroid hormone in pediatric patients with GHD. During the course of treatment, the changes in thyroid function in pediatric patients with GHD should be regularly monitored in order to identify any abnormal thyroid function in its early stages.
RESUMO
PURPOSE: The present study aimed to compare the efficacy and safety of recombinant human growth hormone (rhGH) therapy between children with idiopathic short stature (ISS) and growth hormone deficiency (GHD). METHODS: A total of 150 pediatric patients with ISS and 153 pediatric patients with GHD who received rhGH treatment for more than one year from 2005 to 2016 were enrolled. Growth velocity (GV); height standard deviation (HtSD); insulin-like growth factor-1 standard deviation (IGF-1SD); body mass index (BMI); and the incidence of fasting hyperglycemia, fasting hyperinsulinemia, and hypothyroidism were recorded and compared. RESULTS: At the beginning of treatment, chronological age, bone age, height, and BMI were not statistically significant between the two groups. rhGH dosage in ISS was significantly higher compared with GHD (P = 0). GV from half a year to three years after rhGH therapy was higher in the GHD group compared with the ISS group, but the differences were not statistically significant (P > 0 .05). HtSD increased in the two groups after rhGH therapy. HtSD at the beginning and after three years of therapy was not different between groups except for after half a year of therapy. HtSD in patients with ISS was significantly higher compared with GHD (P < 0 .05). The incidence of hypothyroidism was significantly higher in the GHD group compared with the ISS group (13.72% vs. 6.0%; P < 0.05). Moreover, the incidence of hyperinsulinemia was significantly higher in the ISS group compared with the GHD group (15.33% vs. 7.84%; P < 0 .05). CONCLUSIONS: rhGH increases growth in children with ISS and GHD. Fasting insulin and thyroid function were closely monitored for long-term follow up.
Assuntos
Biomarcadores/sangue , Nanismo Hipofisário/tratamento farmacológico , Transtornos do Crescimento/tratamento farmacológico , Hormônio do Crescimento Humano/administração & dosagem , Proteínas Recombinantes/administração & dosagem , Adolescente , Estatura , Criança , Pré-Escolar , Nanismo Hipofisário/sangue , Nanismo Hipofisário/patologia , Feminino , Seguimentos , Transtornos do Crescimento/sangue , Transtornos do Crescimento/patologia , Hormônio do Crescimento Humano/deficiência , Humanos , Fator de Crescimento Insulin-Like I/análise , Masculino , PrognósticoRESUMO
Since X-linked chronic granulomatosis disease (X-CGD) exhibits no specific clinical symptoms at an early stage, early diagnosis is difficult and depends predominantly on neonatal screening. Therefore, the aim of this study was to explore routine biomarkers for X-CGD in children and provide clues for early diagnosis. The cases of 10 children with X-CGD diagnosed at Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology from 2013 to 2016 and 122 Chinese children with X-CGD reported in the literature were summarized. Serum biomarkers and clinical symptoms at acute infection were organized. A total of 132 children with X-CGD were enrolled in this study. For 55.8% of the patients, the diagnosis was delayed more than one year after the onset of the first symptoms because no typical clinical symptoms manifested. Children with X-CGD at an acute infection stage showed three recurrent signs in terms of serum biomarkers: (1) the total number of white blood cells (especially N%) was increased significantly, accompanied by anemia in some cases; (2) C-reactive protein (CRP) levels were increased significantly; and (3) most of the patients exhibited very high serum IgG levels (>12 g/L). Diagnosis of X-CGD at an early age is difficult because of its nonspecific clinical features. Our study suggested children with X-CGD suffering acute infection show increases in three typical serum biomarkers, which can provide clues for early diagnosis.
Assuntos
Biomarcadores/sangue , Doença Granulomatosa Crônica/sangue , Doença Granulomatosa Crônica/diagnóstico , Proteína C-Reativa/metabolismo , Pré-Escolar , Doença Crônica , Diagnóstico Precoce , Feminino , Humanos , Imunoglobulina G/sangue , Lactente , Leucócitos/fisiologia , MasculinoRESUMO
OBJECTIVE: This study aims to investigate the efficacy and safety of recombinant human growth hormone (rhGH) in the treatment of idiopathic short stature (ISS). METHODS: The data of 200 ISS children, who were treated with rhGH from January 2008 to December 2016, were collected and retrospectively analyzed. The data of height, bone age(BA), chronological age(CA), fasting blood glucose, fasting insulin, thyroid function and IGF-1 were collected, and annual growth velocity (GV), height standard deviation score (HtSDS) and related factors that affect GV were statistically analyzed. RESULTS: (1) GV and HtSDS changes: As the time of treatment increased, the GV decreased year by year. The GV in the second year was significantly lower than that in the first year (Pâ¯<â¯.0001), and the GV in the fourth year was significantly lower than that in the third year (Pâ¯<â¯.05). HtSDS gradually increased from the first year to the third year, and became significantly higher than that in the year before the treatment (Pâ¯<â¯.01). The difference in the increase in HtSDS between the fourth year and third year was not statistically significant (Pâ¯>â¯.05). (2) The influence factors of GV included age at initial treatment, IGF-1SDS during treatment and GV in the year before treatment. (3) The most common side effects during treatment included transient hyperglycemia and temporary hyperinsulinemia, and these returned to normal after the treatment was stopped. Some patients presented with accelerated bone age growth after two years of treatment (annual growth of bone age â³BA was >2â¯years), compared with children without accelerated bone age growth, and the difference between BA and CA (BA-CA) was significantly reduced at the beginning of the treatment (Pâ¯<â¯.01). CONCLUSION: rhGH has a good growth promoting effect on ISS children. A variety of factors may affect the GV, and related adverse reactions should be monitored during the treatment.
Assuntos
Estatura/efeitos dos fármacos , Nanismo/tratamento farmacológico , Transtornos do Crescimento/tratamento farmacológico , Hormônio do Crescimento Humano/uso terapêutico , Determinação da Idade pelo Esqueleto , Criança , China , Nanismo/metabolismo , Feminino , Gráficos de Crescimento , Transtornos do Crescimento/metabolismo , Hormônio do Crescimento Humano/deficiência , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Estudos RetrospectivosRESUMO
Periventricular white matter injury (PWMI) is very common in survivors of premature birth, and the final outcomes are a reduction in myelinated neurons leading to white matter hypomyelination. How and (or) why the oligodendrocyte lineage develops abnormally and myelination is reduced is a hot topic in the field. This study focuses on the effect of intrauterine inflammation on the proliferation of oligodendrocyte lineage cells and the underlying mechanisms. Lipopolysaccharide (LPS) (300 µg/kg) was intraperitoneally injected into pregnant Sprague-Dawley rats at embryonic days 19 and 20 to establish a rat model of intrauterine infection-induced white matter injury. Corpus callosum tissues were collected at postnatal day 14 (P14) to quantify the number of oligodendrocytes, the number and proliferation of oligodendrocyte precursor cells (OPCs), and the expression of myelin proteins (MBP and PLP). Furthermore, the expression of Wnt and Notch signaling-related proteins was analyzed. The results showed that the number of oligodendrocytes in the corpus callosum tissues of LPS-treated rats was reduced, and the expression levels of myelinating proteins were down-regulated. Further analysis showed that the Notch signaling pathway was down-regulated in the LPStreated group. These results indicate that intrauterine LPS may inhibit the proliferation of OPCs by down-regulating the Notch rather than the Wnt signaling pathway, leading to hypomyelination of white matter.
Assuntos
Lesões Encefálicas/tratamento farmacológico , Infecções/tratamento farmacológico , Leucoencefalopatias/tratamento farmacológico , Lipopolissacarídeos/administração & dosagem , Animais , Animais Recém-Nascidos , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Lesões Encefálicas/genética , Lesões Encefálicas/fisiopatologia , Linhagem da Célula/genética , Proliferação de Células/efeitos dos fármacos , Corpo Caloso/metabolismo , Corpo Caloso/fisiopatologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Humanos , Infecções/genética , Infecções/fisiopatologia , Leucoencefalopatias/genética , Leucoencefalopatias/fisiopatologia , Proteína Básica da Mielina/genética , Proteína Proteolipídica de Mielina/genética , Células Precursoras de Oligodendrócitos/efeitos dos fármacos , Gravidez , Ratos , Receptores Notch/genética , Transdução de Sinais/efeitos dos fármacosRESUMO
Laron syndrome is an autosomal recessive disorder caused by defects of growth hormone receptor (GHR) gene. It is characterized by severe postnatal growth retardation and characteristic facial features as well as high circulating levels of growth hormone (GH) and low levels of insulin-like growth factor I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3). This report described the clinical features and GHR gene mutations in 2 siblings with Laron syndrome in a Chinese family. Their heights and weights were in the normal range at birth, but the growth was retarded after birth. When they presented to the clinic, the heights of the boy (8 years old) and his sister (11 years old) were 80.0 cm (-8.2 SDS) and 96.6 cm (-6.8 SDS) respectively. They had typical appearance features of Laron syndrome such as short stature and obesity, with protruding forehead, saddle nose, large eyes, sparse and thin silky hair and high-pitched voice. They had higher basal serum GH levels and lower serum levels of IGF-I, IGFBP-3 and growth hormone binding protein (GHBP) than normal controls. The peak serum GH level after colonidine and insulin stimulations in the boy was over 350 ng/mL. After one-year rhGH treatment, the boy's height increased from 80.0 cm to 83.3 cm. The gene mutation analysis revealed that two patients had same homozygous mutation of S65H (TCA -->CCA) in exon 4, which is a novel gene mutation. It was concluded that a definite diagnosis of Laron syndrome can be made based on characteristic appearance features and serum levels of GH, IGF-I, IGFBP-3 and GHBP. The S65H mutation might be the cause of Laron syndrome in the two patients.