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1.
Sci Transl Med ; 9(376)2017 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-28179501

RESUMO

Diamond-Blackfan anemia (DBA) is a congenital disorder characterized by the failure of erythroid progenitor differentiation, severely curtailing red blood cell production. Because many DBA patients fail to respond to corticosteroid therapy, there is considerable need for therapeutics for this disorder. Identifying therapeutics for DBA requires circumventing the paucity of primary patient blood stem and progenitor cells. To this end, we adopted a reprogramming strategy to generate expandable hematopoietic progenitor cells from induced pluripotent stem cells (iPSCs) from DBA patients. Reprogrammed DBA progenitors recapitulate defects in erythroid differentiation, which were rescued by gene complementation. Unbiased chemical screens identified SMER28, a small-molecule inducer of autophagy, which enhanced erythropoiesis in a range of in vitro and in vivo models of DBA. SMER28 acted through autophagy factor ATG5 to stimulate erythropoiesis and up-regulate expression of globin genes. These findings present an unbiased drug screen for hematological disease using iPSCs and identify autophagy as a therapeutic pathway in DBA.


Assuntos
Anemia de Diamond-Blackfan/tratamento farmacológico , Descoberta de Drogas , Células-Tronco Hematopoéticas/metabolismo , Compostos Alílicos/farmacologia , Anemia de Diamond-Blackfan/patologia , Antígenos CD34/metabolismo , Autofagia/efeitos dos fármacos , Proteína 5 Relacionada à Autofagia/metabolismo , Diferenciação Celular/efeitos dos fármacos , Reprogramação Celular , Células Eritroides/efeitos dos fármacos , Células Eritroides/patologia , Eritropoese/efeitos dos fármacos , Teste de Complementação Genética , Globinas/metabolismo , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Quinazolinas/farmacologia
2.
J Exp Med ; 212(8): 1185-202, 2015 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-26150473

RESUMO

Adenylate kinases (AKs) are phosphotransferases that regulate the cellular adenine nucleotide composition and play a critical role in the energy homeostasis of all tissues. The AK2 isoenzyme is expressed in the mitochondrial intermembrane space and is mutated in reticular dysgenesis (RD), a rare form of severe combined immunodeficiency (SCID) in humans. RD is characterized by a maturation arrest in the myeloid and lymphoid lineages, leading to early onset, recurrent, and overwhelming infections. To gain insight into the pathophysiology of RD, we studied the effects of AK2 deficiency using the zebrafish model and induced pluripotent stem cells (iPSCs) derived from fibroblasts of an RD patient. In zebrafish, Ak2 deficiency affected hematopoietic stem and progenitor cell (HSPC) development with increased oxidative stress and apoptosis. AK2-deficient iPSCs recapitulated the characteristic myeloid maturation arrest at the promyelocyte stage and demonstrated an increased AMP/ADP ratio, indicative of an energy-depleted adenine nucleotide profile. Antioxidant treatment rescued the hematopoietic phenotypes in vivo in ak2 mutant zebrafish and restored differentiation of AK2-deficient iPSCs into mature granulocytes. Our results link hematopoietic cell fate in AK2 deficiency to cellular energy depletion and increased oxidative stress. This points to the potential use of antioxidants as a supportive therapeutic modality for patients with RD.


Assuntos
Adenilato Quinase/metabolismo , Células-Tronco Hematopoéticas/fisiologia , Leucopenia/enzimologia , Leucopenia/fisiopatologia , Estresse Oxidativo/fisiologia , Células-Tronco Pluripotentes/fisiologia , Imunodeficiência Combinada Severa/enzimologia , Imunodeficiência Combinada Severa/fisiopatologia , Laranja de Acridina , Adenilato Quinase/deficiência , Animais , Antioxidantes/farmacologia , Apoptose/fisiologia , Compostos Azo , Sequência de Bases , Diferenciação Celular/efeitos dos fármacos , Biologia Computacional , Primers do DNA/genética , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Dados de Sequência Molecular , Naftalenos , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Peixe-Zebra
3.
BMC Public Health ; 12: 825, 2012 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-23013114

RESUMO

BACKGROUND: The North-east Indian states of Manipur and Nagaland consistently report relatively high HIV prevalence. The targeted HIV prevention interventions in these two states are mostly delivered by non-government organizations (NGOs), and prevention of HIV transmission by injecting drug use is their main focus. Most injecting drug users (IDUs) are male, and the services are primarily tailored to meet their needs, which are not necessarily the same as those for women. This qualitative study describes the health service needs of women who use drugs and alcohol in Manipur and Nagaland, with the goal of identifying strategies and activities that can be implemented by NGOs wanting to improve their reach among vulnerable women. METHODS: In 2009-10, semi-structured in-depth interviews were conducted with 27 key informants and nine focus group discussions (FGDs) with women who use drugs and alcohol, and two FGDs with male IDUs. The thematic areas covered included: the context of female drug and alcohol use; drug and alcohol use patterns; HIV risk behaviours; barriers and facilitators of service use; perceived health needs; and expressed health service needs. The data were recorded, transcribed, translated and thematically analysed. RESULTS: The most problematic substance for women from Nagaland was alcohol, and for women from Manipur it was heroin. The most commonly identified health problems were primarily related to the women's drug and alcohol use, reproductive health and mental health. Other problems of major concern included social exclusion, violence, children's welfare, and financial difficulties. The expressed service needs of these women were women-only integrated health services, women-only detoxification and rehabilitation services, mental health services, desensitization of mainstream health workers, free access to medicines, assistance to meet basic needs, and a safe place for engaging in sex work. CONCLUSION: The expressed health and other service needs of women who use drugs and alcohol in Manipur and Nagaland do not match the services currently provided by HIV prevention NGOs, and this may, in part, account for the relatively poor uptake of these services by women. Strategies and activities that can be implemented by NGOs to strengthen their reach to vulnerable women are identified. However, many of these women's needs are beyond the scope of services typically offered by HIV prevention NGOs, and require a coordinated multi-sectoral response.


Assuntos
Alcoolismo , Serviços de Saúde Comunitária , Infecções por HIV/prevenção & controle , Necessidades e Demandas de Serviços de Saúde , Abuso de Substâncias por Via Intravenosa , Adolescente , Adulto , Alcoolismo/reabilitação , Feminino , Grupos Focais , Acessibilidade aos Serviços de Saúde/economia , Nível de Saúde , Humanos , Índia , Masculino , Transtornos Mentais , Pessoa de Meia-Idade , Pesquisa Qualitativa , Distribuição por Sexo , Classe Social , Abuso de Substâncias por Via Intravenosa/reabilitação , Adulto Jovem
4.
Curr Opin Immunol ; 24(5): 617-24, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22841347

RESUMO

The advent of reprogramming technology has greatly advanced the field of stem cell biology and nurtured our hope to create patient specific renewable stem cell sources. While the number of reports of disease specific induced pluripotent stem cells is continuously rising, the field becomes increasingly more aware that induced pluripotent stem cells are not as similar to embryonic stem cells as initially assumed. Our state of the art understanding of human induced pluripotent stem cells, their capacity, their limitations and their promise as it pertains to the study and treatment of primary immunodeficiencies, is the content of this review.


Assuntos
Diferenciação Celular/imunologia , Síndromes de Imunodeficiência/patologia , Síndromes de Imunodeficiência/terapia , Células-Tronco Pluripotentes/fisiologia , Células-Tronco Pluripotentes/transplante , Medicina Regenerativa/métodos , Animais , Transplante de Células/métodos , Transplante de Células/tendências , Modelos Animais de Doenças , Humanos , Síndromes de Imunodeficiência/fisiopatologia , Células-Tronco Pluripotentes/patologia , Medicina Regenerativa/tendências
5.
Int Psychiatry ; 6(3): 73-74, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31508000

RESUMO

The prevalence of HIV is high in the north-east Indian states of Manipur and Nagaland. The major route of HIV transmission is injecting drug use. Most injecting drug users (IDUs) are male and about 40% are married. The widows of IDUs are among the most disadvantaged people. Many are HIV-infected and experiencing poverty, poor health, social isolation and discrimination, all factors likely to compromise their mental health. Some widows are engaging in HIV risk behaviours, including alcohol and drug misuse, sex work and unprotected sex. There is increasing recognition of the links between poverty and mental health status and risk of HIV infection. People with poor mental health are more likely to engage in HIV risk behaviours.

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