LEONARDO YUJI TANAKA
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina
LIM/64, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/64, Hospital das Clínicas, Faculdade de Medicina - Líder
5 resultados
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conferenceObject Early exposure to high-sucrose diet triggers hippocampal endoplasmic reticulum-stress in young rats(2016) PAES, Antonio Marcus de Andrade; PINTO, Bruno Araujo Serra; MELO, Thamys Marinho; FLISTER, Karla Frida Torres; FRANCA, Lucas Martins; TANAKA, Leonardo Yudi; LAURINDO, Francisco Rafael Martins- Peri/Epicellular Protein Disulfide Isomerase Sustains Vascular Lumen Caliber Through an Anticonstrictive Remodeling Effect(2016) TANAKA, Leonardo Y.; ARAUJO, Haniel A.; HIRONAKA, Gustavo K.; ARAUJO, Thais L. S.; TAKIMURA, Celso K.; RODRIGUEZ, Andres I.; CASAGRANDE, Annelise S.; GUTIERREZ, Paulo S.; LEMOS-NETO, Pedro Alves; LAURINDO, Francisco R. M.Whole-vessel remodeling critically determines lumen caliber in vascular (patho)physiology, and it is reportedly redox-dependent. We hypothesized that the cell-surface pool of the endoplasmic reticulum redox chaperone protein disulfide isomerase-A1 (peri/epicellular=pecPDI), which is known to support thrombosis, also regulates disease-associated vascular architecture. In human coronary atheromas, PDI expression inversely correlated with constrictive remodeling and plaque stability. In a rabbit iliac artery overdistension model, there was unusually high PDI upregulation (approximate to 25-fold versus basal, 14 days postinjury), involving both intracellular and pecPDI. PecPDI neutralization with distinct anti-PDI antibodies did not enhance endoplasmic reticulum stress or apoptosis. In vivo pecPDI neutralization with PDI antibody-containing perivascular gel from days 12 to 14 post injury promoted 25% decrease in the maximally dilated arteriographic vascular caliber. There was corresponding whole-vessel circumference loss using optical coherence tomography without change in neointima, which indicates constrictive remodeling. This was accompanied by decreased hydrogen peroxide generation. Constrictive remodeling was corroborated by marked changes in collagen organization, that is, switching from circumferential to radial fiber orientation and to a more rigid fiber type. The cytoskeleton architecture was also disrupted; there was a loss of stress fiber coherent organization and a switch from thin to medium thickness actin fibers, all leading to impaired viscoelastic ductility. Total and PDI-associated expressions of 1-integrin, and levels of reduced cell-surface 1-integrin, were diminished after PDI antibody treatment, implicating 1-integrin as a likely pecPDI target during vessel repair. Indeed, focal adhesion kinase phosphorylation, a downstream 1-integrin effector, was decreased by PDI antibody. Thus, the upregulated pecPDI pool tunes matrix/cytoskeleton reshaping to counteract inward remodeling in vascular pathophysiology.
- Early and sustained exposure to high-sucrose diet triggers hippocampal ER stress in young rats(2016) PINTO, Bruno Araujo Serra; MELO, Thamys Marinho; FLISTER, Karla Frida Torres; FRANCA, Lucas Martins; KAJIHARA, Daniela; TANAKA, Leonardo Yuji; LAURINDO, Francisco Rafael Martins; PAES, Antonio Marcus de AndradeEarly-life environmental insults have been shown to promote long-term development of chronic non-communicable diseases, including metabolic disturbances and mental illnesses. As such, premature consumption of high-sugar foods has been associated to early onset of detrimental outcomes, whereas underlying mechanisms are still poorly understood. In the present study, we sought to investigate whether early and sustained exposure to high-sucrose diet promotes metabolic disturbances that ultimately might anticipate neurological injuries. At postnatal day 21, weaned male rats started to be fed a standard chow (10 % sucrose, CTR) or a high-sucrose diet (25 % sucrose, HSD) for 9 weeks prior to euthanasia at postnatal day 90. HSD did not alter weight gain and feed efficiency between groups, but increased visceral, non-visceral and brown adipose tissue accumulation. HSD rats demonstrated elevated blood glucose levels in both fasting and fed states, which were associated to impaired glucose tolerance. Peripheral insulin sensitivity did not change, whereas hepatic insulin resistance was supported by increased serum triglyceride levels, as well as higher TyG index values. Assessment of hippocampal gene expression showed endoplasmic reticulum (ER) stress pathways were activated in HSD rats, as compared to CTR. HSD rats had overexpression of unfolded protein response sensors, PERK and ATF6; ER chaperone, PDIA2 and apoptosis-related genes, CHOP and Caspase 3; but decreased expression of chaperone GRP78. Finally, HSD rats demonstrated impaired neuromuscular function and anxious behavior, but preserved cognitive parameters. In conclusion, our data indicate that early exposure to HSD promote metabolic disturbances, which disrupt hippocampus homeostasis and might precociously affect its neurobehavioral functions.
conferenceObject Early exposure to high-sucrose diet triggers hippocampal endoplasmic reticulum-stress in young rats(2016) PAES, Antonio Marcus de Andrade; PINTO, Bruno Araujo Serra; MELO, Thamys Marinho; FLISTER, Karla Frida Torres; FRANCA, Lucas Martins; TANAKA, Leonardo Yudi; LAURINDO, Francisco Rafael MartinsbookPart Forças hemodinâmicas no endotélio: da mecanotransdução às implicações no desenvolvimento da aterosclerose(2016) FERNANDES, Denise C.; LAURINDO, Francisco Rafael Martins; ARAUJO, Thaís L. S.; TANAKA, Leonardo Y.