ABSTRACT
Background@#Henoch-Schonlein purpura nephritis (HSPN) is a very common secondary kidney disease of childhood. Its pathogenesis and the treatment mechanism of glucocorticoid have not been fully elucidated. The aim of this study was to determine the relationship between p300 and the pathogenesis, glucocorticoid therapy in mice with HSPN, respectively.@*Methods@#Forty-eight C57BL/6N male mice, weighing 18 to 20 g, were selected (3–4 weeks old, n = 8 per group). The mice in the normal control group (Group I) were given normal solvent and the HSPN model group (Group II) were given sensitizing drugs. The mice in Group III were injected intraperitoneally with dexamethasone after being given sensitizing drugs. Meanwhile, mice in Groups IV, V and VI with conditional knockout of p300 were also given normal solvent, sensitizing drugs and dexamethasone. The levels of serum IgA, creatinine, and circulating immune complex (CIC) concentrations, 24 h urinary protein and urinary erythrocyte in C57 wild mice, and p300 conditional knockout mice in each group were measured. The expression of p300 in renal tissues and the expression of glucocorticoid receptor (GR) α and β, transforming growth factor (TGF)-β1, and activator protein (AP)-1 after dexamethasone treatment were determined by real-time polymerase chain reaction and Western blotting.@*Results@#Compared with the normal solvent control group (Group I), the expression of p300 mRNA in the model group (Group II) was significantly up-regulated. Western blotting further confirmed the result. Urinary erythrocyte count, 24 h urinary protein quantification, serum IgA, CIC, and renal pathologic score in Group V were distinctly decreased compared with non-knockout mice in Group II (9.7 ± 3.8 per high-power field [/HP] vs. 18.7 ± 6.2/HP, t = 1.828, P = 0.043; 0.18 ± 0.06 g/24 h vs. 0.36 ± 0.08 g/24 h, t = 1.837, P = 0.042; 18.78 ± 0.85 mg/mL vs. 38.46 ± 0.46 mg/mL, t = 1.925, P = 0.038; 0.80 ± 0.27 μg/mL vs. 1.64 ± 0.47 μg/mL, t = 1.892, P = 0.041; 7.0 ± 0.5 vs. 18.0 ± 0.5, t = 1.908, P = 0.039). Compared with non-knockout mice (Group III), the level of urinary erythrocyte count and serum IgA in knockout mice (Group VI) increased significantly after treatment with dexamethasone (3.7 ± 0.6/HP vs. 9.2 ± 3.5/HP, t = 2.186, P = 0.024; 12.38 ± 0.26 mg/mL vs. 27.85 ± 0.65 mg/mL, t = 1.852, P = 0.041). The expression level of GRα was considerably increased in the knockout group after dexamethasone treatment compared with non-knockout mice in mRNA and protein level (t = 2.085, P = 0.026; t = 1.928, P = 0.035), but there was no statistically significant difference in the expression level of GRβ between condition knockout and non-knockout mice (t = 0.059, P = 0.087; t = 0.038, P = 1.12). Furthermore, the expression levels of glucocorticoid resistance genes (AP-1 and TGF-β1) were notably increased after p300 knockout compared with non-knockout mice in mRNA and protein level (TGF-β1: t = 1.945, P = 0.034; t = 1.902, P = 0.039; AP-1: t = 1.914, P = 0.038; t = 1.802, P = 0.041).@*Conclusions@#p300 plays a crucial role in the pathogenesis of HSPN. p300 can down-regulate the expression of resistance genes (AP-1 and TGF-β1) by binding with GRα to prevent further renal injury and glucocorticoid resistance. Therefore, p300 is a promising new target in glucocorticoid therapy in HSPN.
ABSTRACT
La hiperplasia suprarrenal congénita no clásica puede ser asintomática o presentar signos de hiperandrogenismo y requerir tratamiento. Se describen las características clínicas en el diagnóstico, tratamiento y seguimiento hasta alcanzar la talla adulta en cuatro varones. La edad en el momento del diagnóstico fue de 9,2 a 11,6 años. Los motivos de consulta fueron pubarca precoz (n= 2), edad ósea acelerada (n= 1) y pubertad precoz (n= 1). Todos los pacientes presentaron 17-hidroxiprogesterona elevada y el estudio molecular confirmó el diagnóstico. La edad ósea adelantada respecto de la edad cronológica (13,1 ± 0,5 contra 10,2 ± 1,1; p = 0,008) motivó el inicio del tratamiento con hidrocortisona. Durante el seguimiento, la media de talla disminuyó 1,4 ± 0,4 desviaciones estándar (DE) con respecto al diagnóstico (p= 0,007). Sin embargo, la media de talla final no difirió de la genética (-0,9 ± 0,7 contra -0,04 ± 0,5 DE; p= 0,054). Conclusión: El tratamiento de los cuatro niños con adelanto de la edad ósea en el momento del diagnóstico permitió lograr una talla adulta que no difirió de la talla genética.
Although corticoid replacement is recommended for those lateonset adrenal hyperplasia with clinical manifestations, asymptomatic patients do not need treatment. We describe clinical features at diagnosis, treatment, and growth till adult- height, in 4 boys. At diagnosis, age ranged from 9.2-11.6 years. The initial symptoms/signs were: precocious pubarche (n= 2), accelerated bone age (n= 1) and precocious puberty (n= 1). All of them presented elevated 17 hydroxyprogesterone levels and were compound heterozygotes carrying p.V281L mutation. Since, at diagnosis, bone age was significantly advanced for chronological age (13.1 ± 0.5 vs. 10.2 ± 1.1 p= 0.008), hydrocortisone therapy was initiated. During follow-up, mean height Z score decreased 1.4 ± 0.4 SDS (p= 0.007), though adult mean height was not different from target height (-0.39 ± 0.7 vs. -0.04 ± 0.5 SDS, p= 0.054). In conclusion, in 4 symptomatic patients, accurate treatment of late-onset adrenal hyperplasia led to an adult mean height not different from target height. Advanced bone age at diagnosis and the loss of height during pubertal development suggest the need of therapy.