112 research outputs found
Steroidâquinoline hybrids for disruption and reversion of protein aggregation processes
Reversing protein aggregation within cells may be an
important tool to fight protein-misfolding disorders such as Alzheimerâs,
Parkinsonâs, and cardiovascular diseases. Here we report the design and
synthesis of a family of steroidâquinoline hybrid compounds based on
the framework combination approach. This set of hybrid compounds
effectively inhibited AÎČ1â42 self-aggregation in vitro by delaying the
exponential growth phase and/or reducing the quantity of fibrils in the
steady state. Their disaggregation efficacy was further demonstrated
against preaggregated AÎČ1â42 peptides in cellular assays upon their
endocytosis by neuroblastoma cells, as they reverted both the number
and the average area of fibrils back to basal levels. The antiaggregation
effect of these hybrids was further tested and demonstrated in a cellular
model of general protein aggregation expressing a protein aggregation fluorescent sensor. Together, our results show that the new
cholesterolâquinoline hybrids possess wide and marked disaggregation capacities and are therefore promising templates for the
development of new drugs to deal with conformational disorders.Thanks are due to the University of Aveiro, FCT/MEC,
Centro 2020 and Portugal2020, the COMPETE Program, and
the European Union (FEDER Program) via the financial
support to the research units LAQV-REQUIMTE (UIDB/50006/2020), IBiMED (UID/BIM/04501/2019) and CICECO-
Aveiro Institute of Materials (UID/CTM/50011/2019),
financed by national funds through the FCT/MCTES, to the
Portuguese NMR Network, to the ThiMES Project (POCI-01-
0145-FEDER-016630), and to the PAGE Project âProtein
Aggregation Across the Lifespanâ (CENTRO-01-0145-
FEDER-000003), including postdoctoral grants to H.M.T.A.
(BPD/UI98/4861/2017) and R.N.d.S. (BPD/UI98/6327/2018). M.P. was supported by Ph.D. Grant SFRH/BD/135655/2018. A.R.S. and S.G. were supported by national
funds (OE) through FCT, I.P., in the scope of the framework
contract foreseen in numbers 4, 5, and 6 of Article 23 of the
Decree-Law 57/2016 of August 29, changed by Law 57/2017
of July 19. Microphotographs were acquired in the LiM facility
of iBiMED/UA, a member of the Portuguese Platform of
BioImaging (PPBI) (POCI-01-0145-FEDER-022122).info:eu-repo/semantics/publishedVersio
Anticorpos lĂticos induzidos por infecção pelo Trypanosoma cruzi reconhecem epitopos presentes nas formas tripomastigotas e epimastigotas do parasita
Sera of Chaga's disease patients containing anti-T. cruzi lytic antibodies were submitted to affinity chromatography using Sepharose 4B conjugated with antigen extracted from epimasiigote or trypomasiigote forms of the parasite. Epimastigotes were obtained from culture at the exponential growth phase and the trypomastigotes from blood of infected and immunosuppressed mice. Antigen of both parasite forms was obtained by sonication of the parasites followed by centrifugation. Both antigens were then conjugated to activated Sepharose 4B. Affinity chromatography was performed by passing sera from chagasic patients through an immunoadsorbent column containing either epimasiigote or trypomasiigote antigens. Antibodies bound to the column were eluted with cold 0,2 M glycine buffer pH 2,8. The eluted antibodies were analysed regarding their isotype and lytic activity. The results showed that anti-T. cruzi lytic antibodies present in sera from chagasic patients are mainly located in the IgG isotype and recognize epitopes present in both trypomasiigote and epimastigote forms. A brief report of this work has already been published12.Soro de pacientes com doença de Chagas na fase crĂŽnica foram submetidos a cromatografia de afinidade com Sepharose 4B conjugada com um extrato antigĂȘnico obtido de formas epimastigotas ou tripomastigotas de T. cruzi: os epimastigotas foram obtidos de cultura na fase exponencial de crescimento e os tripomastigotas de sangue de camundongos infectados e imunossuprimidos. Os antĂgenos de ambas formas parasitĂĄrias foram obtidos por tratamento dos parasitas por ultra-som, seguido de centrifugação. A cromatografia de afinidade foi feita passando-se os soros chagĂĄsicos atravĂ©s de uma coluna de imunoadsorvente contendo antĂgenos de epimastigotas ou tripomastigotas. Os anticorpos foram eluĂdos da coluna com tampĂŁo glicina 0,2 M pH 2,8 a 4°C. Os anticorpos eluidos foram analisados quanto ao seu isotipo e atividade lĂtica. Os resultados mostraram que os anticorpos anti-T. cruzi com atividade lĂtica presentes em soros chagĂĄsicos estĂŁo localizados no isotipo IgG e reconhecem epitopos presentes tanto nos tripomastigotas quanto nos epimastigotas
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