RESUMEN
Brain-derived neurotropic factor (BDNF) deficiency in Schwann cells plays an important role in the pathogenesis of diabetic peripheral neuropathy (DPN). Little is known about the mechanism involved in BDNF downregulation in Schwann cells in DPN. In this study, we first confirmed downregulation of BDNF and neurotrophin 3 expression in the sciatic nerves of diabetic mice, which was accompanied by myelin sheath abnormalities. Moreover, in vitro, high glucose was revealed to cause downregulation of BDNF, but not neurotrophin 3, expression in RSC96â¯cells, which was accompanied by DNA hypermethylation of BDNF promoters I and II. DNMT1 was subsequently revealed to be enhanced at the mRNA and protein levels in high glucose-stimulated RSC96â¯cells, and inhibition of DNMT1 with 5-Aza treatment or shRNA vector transfection reversed high glucose-induced reductions in BDNF expression. Furthermore, the mTOR and upstream Akt pathways were indicated to mediate high glucose-induced DNMT1 and BDNF expression in RSC96â¯cells. Taken together, our results suggest that the Akt/mTOR cascade mediates high glucose-induced reductions in BDNF via DNMT1 in Schwann cells in DPN.
Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/metabolismo , Neuropatías Diabéticas/patología , Regulación de la Expresión Génica/efectos de los fármacos , Glucosa/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Células de Schwann/patología , Serina-Treonina Quinasas TOR/metabolismo , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Células Cultivadas , Metilación de ADN , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/metabolismo , Neuropatías Diabéticas/etiología , Neuropatías Diabéticas/metabolismo , Regulación hacia Abajo , Masculino , Ratones , Neurotrofina 3/genética , Neurotrofina 3/metabolismo , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas c-akt/genética , Ratas , Células de Schwann/efectos de los fármacos , Células de Schwann/metabolismo , Nervio Ciático/efectos de los fármacos , Nervio Ciático/metabolismo , Nervio Ciático/patología , Edulcorantes/farmacología , Serina-Treonina Quinasas TOR/genéticaRESUMEN
BACKGROUND/AIM: We aimed to evaluate the histopathologic characteristics of HBeAg-negative chronic hepatitis B patients with low hepatitis B virus (HBV) DNA levels (<2000 IU/mL) and persistently normal ALT levels and to determine indicators of significant liver disease. METHODS: We examined 102 consecutive subjects who underwent percutaneous liver biopsy. Significant predictors of liver disease (stage ≥2 fibrosis or stage 1 fibrosis plus grade ≥2 inflammation), including demographic, clinical, and laboratory variables, were evaluated by means of univariate and multivariate logistic regression analyses. RESULTS: Among the patients, 75.5% (77/102) had grade 0-1 inflammation and 77.5% (79/102) had stage 0-1 fibrosis. However, 38.2% (39/102) had significant liver disease. There were no statistically significant differences in clinical parameters such as age, biochemical profile, HBV DNA levels, HBsAg levels, and platelet count between patients with significant and those with nonsignificant liver disease. Patients with significant liver disease had higher values of aspartate transferase-to-platelet ratio index (APRI) and FIB-4 index compared with those with nonsignificant liver disease (0.35±0.21 vs. 0.27±0.12, P=0.02; 1.58±0.97 vs. 1.13±0.54, P=0.009, respectively). The area under the receiver operating characteristic (AUROC) curve of APRI for identifying active liver histology was 0.64 (95% CI, 0.53-0.75; P=0.019); the cutoff value was 0.24 with a sensitivity of 74% and specificity of 55%. In comparison, FIB-4 had equal power (the AUROC was 0.66) in predicting active liver histology. CONCLUSION: Among patients presenting with low HBV DNA levels and normal ALT levels, about 38.2% had significant liver disease. Neither serum HBsAg nor HBV DNA levels correlate with liver histology. However, APRI≥0.24 might be considered an indicator of liver biopsy.
Asunto(s)
Alanina Transaminasa/sangre , Biomarcadores/sangre , Hepatitis B Crónica/patología , Cirrosis Hepática/patología , Adulto , Anciano , Pueblo Asiatico , China , Femenino , Antígenos e de la Hepatitis B/sangre , Hepatitis B Crónica/sangre , Hepatitis B Crónica/virología , Humanos , Cirrosis Hepática/sangre , Cirrosis Hepática/virología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Carga Viral , Adulto JovenRESUMEN
BACKGROUND/AIM: We aimed to develop a clinically useful scoring system to predict the probability of significant fibrosis (the Scheuer score ≥S2) in patients with chronic hepatitis B infection (CHB) and alanine aminotransferase (ALT) levels 2-fold lower than the upper limit of normal (ULN), in order to facilitate the clinical decision to perform a subsequent liver biopsy. METHODS: Consecutive subjects who underwent percutaneous liver biopsy were examined. The predictors evaluated included demographic, clinical, and laboratory variables. A clinical scoring system was developed by rounding the estimated regression coefficients for the independent predictors in multivariate logistic models for the diagnosis of significant fibrosis. RESULTS: A total of 283 patients with ALT levels 2-fold lower than the ULN were divided into 2 groups to develop (n=190) and validate (n=93) the scoring system. Of the 190 subjects examined, 52 (27.4%) had significant fibrosis. Aspartate transferase levels, platelet counts, and hepatitis B surface antigen levels were independently associated with significant liver fibrosis. A fibrosis clinical scoring system comprising these 3 variables in CHB patients with ALT levels 2-fold lower than the ULN was developed to predict the probability of significant fibrosis in 4 categories (low, intermediate, high, and very high risk). CONCLUSIONS: The proposed fibrosis scoring system predicted the probability of significant fibrosis in CHB patients with ALT levels 2-fold lower than the ULN with sufficient accuracy. It identified individuals with a very high risk for significant fibrosis in whom liver biopsy would most likely yield a diagnostic benefit. It also identified individuals with a low risk of moderate fibrosis in whom a liver biopsy can be delayed or avoided.
Asunto(s)
Alanina Transaminasa/sangre , Aspartato Aminotransferasas/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis B Crónica/complicaciones , Cirrosis Hepática/enzimología , Cirrosis Hepática/patología , Hígado/patología , Adulto , Área Bajo la Curva , Biomarcadores/sangre , Biopsia , Femenino , Hepatitis B Crónica/enzimología , Humanos , Cirrosis Hepática/etiología , Masculino , Recuento de Plaquetas , Valor Predictivo de las Pruebas , Estudios Prospectivos , Curva ROC , Índice de Severidad de la Enfermedad , Adulto JovenRESUMEN
RATIONALE: Anti-glomerular basement membrane (anti-GBM) disease has been reported to coexist with other immune-mediated glomerular disorders, including antineutrophil cytoplasmic autoantibody positive glomerulonephritis and membranous glomerulopathy. It is well known that anti-GBM disease often manifests as type I crescentic glomerulonephritis on renal biopsy. However, concurrent cases of both type I crescentic glomerulonephritis and IgA nephropathy are rare. PATIENT CONCERNS: We report the case of a 40-years-old woman with microscopic hematuria, mild proteinuria and an immunocompromised status. Laboratory data revealed serum creatinine showed progressive progress, suddenly rising from the normal range to 316.2µmol/L within 4 months. The CD4 lymphocyte count was 0.274 × 109/L (reference value 0.35-1.82 × 109/L). The anti-GBM antibody titer was 192.4 IU/mL (reference range: <20 RU/mL). DIAGNOSES: Renal biopsy was performed after admission. The pathological diagnosis was type I crescentic glomerulonephritis, IgA nephropathy, and clinical anti-GBM disease. INTERVENTIONS: The patient was seriously ill on admission and progressed rapidly. Combined with poor immune function, we immediately initiated high-frequency plasma exchange (PE). In addition, to avoid rebound of antibody levels, PE was performed for 5 times. Follow-up treatment was combined with standard-dose corticosteroids and cyclophosphamide. OUTCOMES: The patient was followed up for 1 year. On the last visit, her serum creatinine decreased to 103.5µmol/L, anti-GBM antibody remained negative, and proteinuria and hematuria disappeared. LESSONS: This case illustrates that when crescentic nephritis or anti-GBM disease is combined with other immune diseases, especially when the immune function is extremely low, if the application of high-dose steroid shocks may induce fatal infections, to some extent high frequency PE has certain advantages.
Asunto(s)
Enfermedad por Anticuerpos Antimembrana Basal Glomerular , Glomerulonefritis por IGA , Glomerulonefritis Membranoproliferativa , Glomerulonefritis , Humanos , Femenino , Adulto , Glomerulonefritis por IGA/complicaciones , Glomerulonefritis por IGA/terapia , Glomerulonefritis por IGA/diagnóstico , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/complicaciones , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/terapia , Intercambio Plasmático/efectos adversos , Hematuria/etiología , Hematuria/terapia , Creatinina , Glomerulonefritis/complicaciones , Glomerulonefritis/terapia , Enfermedad Aguda , Proteinuria/terapiaRESUMEN
BACKGROUND/AIM: The purpose of this study was to determine the relationship between hepatitis B e antigen (HBeAg) and hepatitis B surface antigen (HBsAg) levels and liver histology in HBeAg-positive patients with chronic hepatitis B virus (CHB) infection. METHODS: Serum HBsAg and HBeAg levels were analyzed, and liver biopsies were obtained from 203 HBeAg-positive CHB patients (62.6 % males; median age 31.3 years). The upper limit of normal (ULN) for ALT in this study was 30 and 19 U/L for males and females, respectively. Histologic assessment was based on Scheuer classification. RESULTS: ALT <2 × ULN, fibrosis stage
RESUMEN
Liver disease can develop in chronic hepatitis B (CHB) patients with normal or mildly elevated alanine aminotransferase (ALT) who seldom undergo liver biopsy. We aimed to determine histologic characteristics of a large cohort of Chinese CHB patients undergoing liver biopsy and to evaluate the utility of ALT and HBV DNA values at the time of biopsy in predicting liver disease in this population. This prospective study enrolled 230 treatment-naïve patients with persistently normal or mildly elevated ALT. All patients had a liver biopsy. ALT, aspartate aminotransferase (AST), and HBV DNA levels were some of the other parameters measured. Using Scheuer's classification, significant histology was defined as stage â§2 fibrosis and/or stage 1 fibrosis plus⧠grade 2 inflammation. Liver disease was observed in 34.4% and 61.8% of patients with normal ALT and mildly elevated ALT, respectively. Patients with mildly elevated ALT levels had significantly more events, including liver disease, elevated AST, and moderate to severe inflammation and liver fibrosis, than patients with normal ALT (all P≤0.005). A total of 107 patients (46.5%) had liver disease and 123 (53.5%) did not. PLT and ALT were significantly associated with liver disease (both P<0.001). Patients with elevated ALT, lower platelet count and HBV DNA < 7 log10copies/mL may have histologically significant changes associated with liver disease. Multivariate analysis showed that PLT and HBV DNA levels were significantly associated with liver disease in patients with normal ALT while gender and HBV DNA levels were significantly associated with liver disease in patients with mildly elevated ALT. Assessing liver damage via biopsy in patients with normal or mildly elevated ALT may help to identify those who would benefit from antiviral therapy.