RESUMO
Recycled cooking oil (RCO) is widely used in many small restaurants. However, the health risk posed by long-term consumption of RCO is unclear. In this study, C57 mice were treated with RCO for 34 weeks. Organ coefficients of the liver, stomach, and kidney were found to be decreased. H&E staining revealed overt lesions in the pancreas, liver, kidney, esophagus, duodenum, and ileum of RCO-treated mice. Immunohistochemistry showed significant DNA damage in the duodenum and ileum and apoptosis in the lungs of the RCO-treated mice. Immunoblotting showed elevated levels of γ-H2AX, Bcl-2/Bax, TNFα, cleaved Caspase-3 and poly ADP-ribose polymerase (PARP). Increased levels of lactate dehydrogenase (LDH) and decreased levels of succinate dehydrogenase (SDH) were also detected. These findings suggest that long-term consumption of RCO produces various toxicities in mice with important implications for humans. DNA damage followed by mitochondria-associated apoptosis, and necrosis is likely to contribute to the toxicities.
Assuntos
Morte Celular , Culinária/normas , Óleos de Plantas/toxicidade , Animais , Caspase 3/genética , Caspase 3/metabolismo , Células Cultivadas , Dano ao DNA , Feminino , Histonas/genética , Histonas/metabolismo , Intestinos/efeitos dos fármacos , Rim/efeitos dos fármacos , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Fígado/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óleos de Plantas/administração & dosagem , Óleos de Plantas/normas , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Estômago/efeitos dos fármacos , Succinato Desidrogenase/genética , Succinato Desidrogenase/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Plasmodium falciparum multidrug resistance constitutes a major obstacle to the global malaria elimination campaign. Specific mutations in the Plasmodium falciparum chloroquine resistance transporter (PfCRT) mediate resistance to the 4-aminoquinoline drug chloroquine and impact parasite susceptibility to several partner agents used in current artemisinin-based combination therapies, including amodiaquine. By examining gene-edited parasites, we report that the ability of the wide-spread Dd2 PfCRT isoform to mediate chloroquine and amodiaquine resistance is substantially reduced by the addition of the PfCRT L272F mutation, which arose under blasticidin selection. We also provide evidence that L272F confers a significant fitness cost to asexual blood stage parasites. Studies with amino acid-restricted media identify this mutant as a methionine auxotroph. Metabolomic analysis also reveals an accumulation of short, hemoglobin-derived peptides in the Dd2 + L272F and Dd2 isoforms, compared with parasites expressing wild-type PfCRT. Physiologic studies with the ionophores monensin and nigericin support an impact of PfCRT isoforms on Ca2+ release, with substantially reduced Ca2+ levels observed in Dd2 + L272F parasites. Our data reveal a central role for PfCRT in regulating hemoglobin catabolism, amino acid availability, and ionic balance in P. falciparum, in addition to its role in determining parasite susceptibility to heme-binding 4-aminoquinoline drugs.
Assuntos
Cloroquina/farmacologia , Resistência a Múltiplos Medicamentos/genética , Eritrócitos/efeitos dos fármacos , Hemoglobinas/metabolismo , Interações Hospedeiro-Parasita , Proteínas de Membrana Transportadoras/genética , Plasmodium falciparum/efeitos dos fármacos , Proteínas de Protozoários/genética , Amodiaquina/farmacologia , Antimaláricos/farmacologia , Artemisininas/farmacologia , Cálcio/metabolismo , Células Cultivadas , Eritrócitos/metabolismo , Eritrócitos/parasitologia , Expressão Gênica , Humanos , Transporte de Íons/efeitos dos fármacos , Ionóforos/farmacologia , Proteínas de Membrana Transportadoras/metabolismo , Monensin/farmacologia , Mutação , Nigericina/farmacologia , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/metabolismo , Pirrolidinonas/farmacologiaRESUMO
Drug resistant strains of the malaria parasite, Plasmodium falciparum, have rendered chloroquine ineffective throughout much of the world. In parts of Africa and Asia, the coordinated shift from chloroquine to other drugs has resulted in the near disappearance of chloroquine-resistant (CQR) parasites from the population. Currently, there is no molecular explanation for this phenomenon. Herein, we employ metabolic quantitative trait locus mapping (mQTL) to analyze progeny from a genetic cross between chloroquine-susceptible (CQS) and CQR parasites. We identify a family of hemoglobin-derived peptides that are elevated in CQR parasites and show that peptide accumulation, drug resistance, and reduced parasite fitness are all linked in vitro to CQR alleles of the P. falciparum chloroquine resistance transporter (pfcrt). These findings suggest that CQR parasites are less fit because mutations in pfcrt interfere with hemoglobin digestion by the parasite. Moreover, our findings may provide a molecular explanation for the reemergence of CQS parasites in wild populations.
