Tatiane Grazieli Hammerschmidt1, Graziela de Oliveira Schmitt Ribas2, Maria Luiza Saraiva-Pereira3, Márcia Polese Bonatto4, Rejane Gus Kessler5, Fernanda Timm Seabra Souza6, Franciele Trapp7, Kristiane Michelin-Tirelli6, Maira Graeff Burin6, Roberto Giugliani8, Carmen Regla Vargas9. 1. Departamento de Análises, Faculdade de Farmácia, UFRGS, Avenida Ipiranga, 2752, CEP 90610-000, Porto Alegre, RS, Brazil; Programa de Pós-Graduação em Ciências Farmacêuticas, UFRGS, Av. Ipiranga, 2752, CEP 90610-000, Porto Alegre, RS, Brazil. Electronic address: tatiane.hammerschmidt@gmail.com. 2. Programa de Pós-Graduação em Ciências Farmacêuticas, UFRGS, Av. Ipiranga, 2752, CEP 90610-000, Porto Alegre, RS, Brazil; Serviço de Genética Médica, HCPA, Rua Ramiro Barcelos, 2350, CEP 90035-003, Porto Alegre, RS, Brazil. 3. Programa de Pós-Graduação em Ciências Biológicas, Bioquímica, UFRGS, Rua Ramiro Barcelos, 2600, CEP 90035-003, Porto Alegre, RS, Brazil; Programa de Pós-Graduação em Ciências Farmacêuticas, UFRGS, Av. Ipiranga, 2752, CEP 90610-000, Porto Alegre, RS, Brazil. 4. Programa de Pós-Graduação em Ciências Biológicas, Bioquímica, UFRGS, Rua Ramiro Barcelos, 2600, CEP 90035-003, Porto Alegre, RS, Brazil. 5. Programa de Pós-Graduação em Ciências Biológicas, Bioquímica, UFRGS, Rua Ramiro Barcelos, 2600, CEP 90035-003, Porto Alegre, RS, Brazil; Departamento de Genética, IB, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. 6. Programa de Pós-Graduação em Ciências Biológicas, Bioquímica, UFRGS, Rua Ramiro Barcelos, 2600, CEP 90035-003, Porto Alegre, RS, Brazil; Serviço de Genética Médica, HCPA, Rua Ramiro Barcelos, 2350, CEP 90035-003, Porto Alegre, RS, Brazil. 7. Serviço de Genética Médica, HCPA, Rua Ramiro Barcelos, 2350, CEP 90035-003, Porto Alegre, RS, Brazil. 8. Programa de Pós-Graduação em Ciências Biológicas, Bioquímica, UFRGS, Rua Ramiro Barcelos, 2600, CEP 90035-003, Porto Alegre, RS, Brazil; Serviço de Genética Médica, HCPA, Rua Ramiro Barcelos, 2350, CEP 90035-003, Porto Alegre, RS, Brazil; Departamento de Genética, IB, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. 9. Departamento de Análises, Faculdade de Farmácia, UFRGS, Avenida Ipiranga, 2752, CEP 90610-000, Porto Alegre, RS, Brazil; Programa de Pós-Graduação em Ciências Biológicas, Bioquímica, UFRGS, Rua Ramiro Barcelos, 2600, CEP 90035-003, Porto Alegre, RS, Brazil; Programa de Pós-Graduação em Ciências Farmacêuticas, UFRGS, Av. Ipiranga, 2752, CEP 90610-000, Porto Alegre, RS, Brazil; Serviço de Genética Médica, HCPA, Rua Ramiro Barcelos, 2350, CEP 90035-003, Porto Alegre, RS, Brazil. Electronic address: crvargas@hcpa.ufrgs.br.
Abstract
BACKGROUND: Niemann-Pick type C (NP-C), one of 50 inherited lysosomal storage disorders, is caused by NPC protein impairment that leads to unesterified cholesterol accumulation in late endosomal/lysosomal compartments. The clinical manifestations of NP-C include hepatosplenomegaly, neurological and psychiatric symptoms. Current diagnosis for NP-C is based on observation of the accumulated cholesterol in fibroblasts of affected individuals, using an invasive and time expensive test, called Filipin staining. Lately, two metabolites that are markedly increased in NP-C patients are arising as biomarkers for this disease screening: 7-ketocholesterol and cholestane-3β,5α,6β-triol, both oxidized cholesterol products. OBJECTIVE: In this work, we aimed to evaluate the performance of cholestane-3β,5α,6β-triol analysis for the screening and monitoring of NPC patients, correlating it with chitotriosidase levels, Filipin staining and molecular analysis. It was investigated 76 non-treated individuals with NP-C suspicion and also 7 patients with previous NP-C diagnosis under treatment with miglustat, in order to verify the cholestane-3β,5α,6β-triol value as a tool for therapy monitoring. RESULTS: Considering molecular assay as golden standard, it was verified that cholestane-3β,5α,6β-triol analysis presented 88% of sensitivity, 96.08% of specificity, a positive and negative predictive value calculated in 91.67% and 94.23%, respectively, for the diagnosis of NP-C. Chitotriosidase levels were increased in patients with positive molecular analysis for NP-C. For Filipin staining, it was found 1 false positive, 7 false negative and 24 inconclusive cases, showing that this assay has important limitations for NP-C diagnosis. Besides, we found a significant decrease in cholestane-3β,5α,6β-triol concentrations in NP-C patients under therapy with miglustat when compared to non-treated patients. CONCLUSION: Taken together, the present data show that cholestane-3β,5α,6β-triol analysis has a high potential to be an important NP-C screening assay, and also can be used for therapy monitorization with miglustat in NP-C patients.
BACKGROUND:Niemann-Pick type C (NP-C), one of 50 inherited lysosomal storage disorders, is caused by NPC protein impairment that leads to unesterified cholesterol accumulation in late endosomal/lysosomal compartments. The clinical manifestations of NP-C include hepatosplenomegaly, neurological and psychiatric symptoms. Current diagnosis for NP-C is based on observation of the accumulated cholesterol in fibroblasts of affected individuals, using an invasive and time expensive test, called Filipin staining. Lately, two metabolites that are markedly increased in NP-Cpatients are arising as biomarkers for this disease screening: 7-ketocholesterol and cholestane-3β,5α,6β-triol, both oxidized cholesterol products. OBJECTIVE: In this work, we aimed to evaluate the performance of cholestane-3β,5α,6β-triol analysis for the screening and monitoring of NPCpatients, correlating it with chitotriosidase levels, Filipin staining and molecular analysis. It was investigated 76 non-treated individuals with NP-C suspicion and also 7 patients with previous NP-C diagnosis under treatment with miglustat, in order to verify the cholestane-3β,5α,6β-triol value as a tool for therapy monitoring. RESULTS: Considering molecular assay as golden standard, it was verified that cholestane-3β,5α,6β-triol analysis presented 88% of sensitivity, 96.08% of specificity, a positive and negative predictive value calculated in 91.67% and 94.23%, respectively, for the diagnosis of NP-C. Chitotriosidase levels were increased in patients with positive molecular analysis for NP-C. For Filipin staining, it was found 1 false positive, 7 false negative and 24 inconclusive cases, showing that this assay has important limitations for NP-C diagnosis. Besides, we found a significant decrease in cholestane-3β,5α,6β-triol concentrations in NP-Cpatients under therapy with miglustat when compared to non-treated patients. CONCLUSION: Taken together, the present data show that cholestane-3β,5α,6β-triol analysis has a high potential to be an important NP-C screening assay, and also can be used for therapy monitorization with miglustat in NP-Cpatients.
Authors: Rohini Sidhu; Yawo Mondjinou; Mingxing Qian; Haowei Song; Arun Babu Kumar; Xinying Hong; Fong-Fu Hsu; Dennis J Dietzen; Nicole M Yanjanin; Forbes D Porter; Elizabeth Berry-Kravis; Charles H Vite; Michael H Gelb; Jean E Schaffer; Daniel S Ory; Xuntian Jiang Journal: J Lipid Res Date: 2019-06-14 Impact factor: 5.922
Authors: Rohini Sidhu; Pamela Kell; Dennis J Dietzen; Nicole Y Farhat; An Ngoc Dang Do; Forbes D Porter; Elizabeth Berry-Kravis; Janine Reunert; Thorsten Marquardt; Roberto Giugliani; Charles M Lourenço; Raymond Y Wang; Nina Movsesyan; Ellen Plummer; Jean E Schaffer; Daniel S Ory; Xuntian Jiang Journal: Mol Genet Metab Date: 2020-11-18 Impact factor: 4.797
Authors: Rohini Sidhu; Pamela Kell; Dennis J Dietzen; Nicole Y Farhat; An Ngoc Dang Do; Forbes D Porter; Elizabeth Berry-Kravis; Charles H Vite; Janine Reunert; Thorsten Marquardt; Roberto Giugliani; Charles M Lourenço; Olaf Bodamer; Raymond Y Wang; Ellen Plummer; Jean E Schaffer; Daniel S Ory; Xuntian Jiang Journal: Mol Genet Metab Date: 2020-01-22 Impact factor: 4.204
Authors: Anna V Degtyareva; Tatiana Y Proshlyakova; Marina S Gautier; Dmitry N Degtyarev; Elena A Kamenets; Galina V Baydakova; Denis V Rebrikov; Ekaterina Y Zakharova Journal: BMC Med Genet Date: 2019-07-11 Impact factor: 2.103