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
10 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 MartinsconferenceObject Peri/epicellular protein disulfide isomerase PDI acts as an organizer of cytoskeletal mechanoadaptation in vascular smooth muscle cells(2018) TANAKA, Leonardo Yuji; ARAUJO, Thais Larissa; RODRIGUEZ, Andres Ignacio; FERRAZ, Mariana Sacrini Ayres; PELEGATI, Vitor Bianchin; SANTOS, Aline Mara; CESAR, Carlos Lens; ALENCAR, Adriano Mesquita; LAURINDO, Francisco Rafael Martins- Evidence for a protective role of Protein Disulfide Isomerase-A1 against aortic dissection(2023) PORTO, Fernando Garcez; TANAKA, Leonardo Yuji; BESSA, Tiphany Coralie de; OLIVEIRA, Percillia Victoria Santos; SOUZA, Julia Martins Felipe de; KAJIHARA, Daniela; FERNANDES, Carolina Goncalves; SANTOS, Patricia Nolasco; LAURINDO, Francisco Rafael MartinsBackground and aims: Redox signaling is involved in the pathophysiology of aortic aneurysm/dissection. Protein Disulfide Isomerases and its prototype PDIA1 are thiol redox chaperones mainly from endoplasmic reticulum (ER), while PDIA1 cell surface pool redox-regulates thrombosis, cytoskeleton remodeling and integrin activation, which are mechanisms involved in aortic disease. Here we investigate the roles of PDIA1 in aortic dissection. Methods: Initially, we assessed the outcome of aortic aneurysm/dissection in transgenic PDIA1-overexpressing FVB mice using a model of 28-day exposure to lysyl oxidase inhibitor BAPN plus angiotensin-II infusion. In a second protocol, we assessed the effects of PDIA1 inhibitor isoquercetin (IQ) against aortic dissection in C57BL/6 mice exposed to BAPN for 28 days. Results: Transgenic PDIA1 overexpression associated with ca. 50% (p = 0.022) decrease (vs.wild-type) in mor-tality due to abdominal aortic rupture and protected against elastic fiber breaks in thoracic aorta. Conversely, exposure of mice to IQ increased thoracic aorta dissection-related mortality rates, from ca. 18%-50% within 28-days (p = 0.019); elastic fiber disruption and collagen deposition were also enhanced. The structurally-related compound diosmetin, which does not inhibit PDI, had negligible effects. In parallel, stretch-tension curves indicated that IQ amplified a ductile-type of biomechanical failure vs. control or BAPN-exposed mice aortas. IQ-induced effects seemed unassociated with nonspecific antioxidant effects or ER stress. In both models, echo-cardiographic analysis of surviving mice suggested that aortic rupture was dissociated from progressive dilatation. Conclusions: Our data indicate a protective role of PDIA1 against aortic dissection/rupture and potentially un-covers a novel integrative mechanism coupling redox and biomechanical homeostasis in vascular remodeling.
- 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.
- Exercise improves endothelial function: A local analysis of production of nitric oxide and reactive oxygen species(2015) TANAKA, Leonardo Yuji; BECHARA, Luiz Roberto Grassmann; SANTOS, Adriana Marques dos; JORDAO, Camila Paixao; SOUSA, Luis Gustavo Oliveira de; BARTHOLOMEU, Teresa; VENTURA, Laura Ines; LAURINDO, Francisco Rafael Martins; RAMIRES, Paulo RizzoThis study aimed at investigating the acute effects of aerobic exercise on endothelium-dependent vasomotor function of rat aorta, as well as mechanisms involved in endothelial nitric oxide (NO) bioactivity. Wistar rats were assigned to either a resting control (C, n = 21) or acutely exercised (E, n = 21) groups (60 min, 55-60% of maximum speed). After exercise, thoracic aorta was excised and cut into rings. Two rings were promptly applied to evaluate vasomotor function and the rest of aorta was used for additional measurements. Acute exercise significantly improved maximum ACh-induced relaxation (C, 91.6 +/- 1.2 vs. E, 102.4 +/- 1.7%, p < 0.001) and sensitivity to ACh (C, -7.3 +/- 0.06 vs. E, -7.3 +/- 0.02 log M, p < 0.01), and was accompanied by significantly increases on serine1177 eNOS phosphorylation, reflecting its enhanced activation. However, acute exercise also enhanced both superoxide and hydrogen peroxide production, as assayed by dihydroethidium oxidation, lucigenin chemiluminescence and Amplex Red assays. We also provided evidence for Nox2 NADPH oxidase (Nox) activation through gp91dstat-mediated inhibition of superoxide signals. Enhanced arterial relaxations associated with acute exercise were nearly-completely prevented by catalase, suggesting a role for paracrine hydrogen peroxide. Despite increased detectable oxidant generation, cellular oxidative stress was not evident, as suggested by unaltered GSH:GSSG ratio and lipid hydroperoxides. Collectively, these results demonstrate that one bout of moderate aerobic exercise improves endothelial function by increasing NO bioavailability, while superoxide and hydrogen peroxide are generated in a controlled fashion.
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 MartinsconferenceObject Role of Protein Disulfide Isomerase during vascular repair after injury(2012) TANAKA, Leonardo Yuji; ARAUJO, Haniel Alves; CSORDAS, Andre Alcantara; HIRONAKA, Gustavo Ken; TAKIMURA, Celso Kiyochi; LAURINDO, Francisco Rafael MartinsEndoplasmic reticulum(ER) redox chaperone protein disulfide isomerase(PDI) regulates vascular/phagocytic NADPH oxidase and supports cell migration. We investigated the role of PDI during vascular repair after injury(AI) induced by balloon in rabbit iliac artery. There was marked increase of PDI mRNA and protein(5–10-fold) at 4, 7 and 14 days AI vs. intact control(CT). PDI immunostaining was greater in intima = neo-endothelium > media. Increased cell-surface PDI was also evident. ER stress-related KDEL chaperones also increased with similar time-course AI. PDI siRNA(siPDI) transfection in cultured vessel rings collected 14 days AI enhanced KDEL expression vs. scrambled siRNA(siScr) (siScr 2.1±0.9 vs. siPDI 5.0±2.3-fold vs. CT, p<0.05), apoptosis (siScr 4.6±0.2 vs. siPDI 6.2±0.9 %TUNEL + nuclei, p<0.05) and proliferation marker PCNA (siScr 1.2±0.3 vs. siPDI 4.0 ±0.2 AU, p<0.05), and decreased differentiation marker calponin-C (siScr 0.52±0.04 vs. siPDI 0.36 ±0.04 AU, p<0.05). siPDI in CT rings did not alter such variables. PCR array analysis showed analogous pattern of mRNA changes. Also, siPDI 14 days AI upregulated Nox1 and downregulated Nox4 NADPH oxidase, while siPDI attenuated oxidant production (in situ hydroethidine) only in CT vessels. Thus, strongly-overexpressed PDI 14 days AI protects against apoptosis and ER stress and sustains VSMC differentiation.bookPart 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.- DNAJB12 and DNJB14 are non-redundant Hsp40 redox chaperones involved in endoplasmic reticulum protein reflux(2024) PURIFICACA, Aline Dias da; DEBBAS, Victor; TANAKA, Leonardo Yuji; GABRIEL, Gabriele Veronica de Mello; WOSNIAK JUNIOR, Joao; BESSA, Tiphany Coralie De; GARCIA-ROSA, Sheila; LAURINDO, Francisco Rafael Martins; OLIVEIRA, Percillia Victoria SantosBackground: The endoplasmic reticulum (ER) transmembrane chaperones DNAJB12(B12) and DNAJB14(B14) are cofactors that cooperate with cytosolic Heat Shock-70 protein (HSC70) facilitating folding/degradation of nascent membrane proteins and supporting the ER-membrane penetration of viral particles. Here, we assessed structural/functional features of B12/B14 with respect to their regulation by ER stress and their involvement in ER stress-mediated protein reflux.Methods: We investigated the effect of Unfolded Protein Response(UPR)-eliciting drugs on the expression/ regulation of B12-B14 and their roles in ER-to-cytosol translocation of Protein Disulfide Isomerase-A1(PDI).Results: We show that B12 and B14 are similar but do not seem redundant. They share predicted structural features and show high homology of their cytosolic J-domains, while their ER-lumen DUF1977 domains are quite dissimilar. Interactome analysis suggested that B12/B14 associate with different biological processes. UPR activation did not significantly impact on B12 gene expression, while B14 transcripts were up-regulated. Meanwhile, B12 and B14 (33.4 kDa isoform) protein levels were degraded by the proteasome upon acute reductive challenge. Also, B12 degradation was impaired upon sulfenic-acid trapping by dimedone. We originally report that knockdown of B12/B14 and their cytosolic partner SGTA in ER-stressed cells significantly impaired the amount of the ER redox-chaperone PDI in a cytosolic-enriched fraction. Additionally, B12 but not B14 overexpression increased PDI relocalization in non-stressed cells.Conclusions and general significance: Our findings reveal that B12/B14 regulation involves thiol redox processes that may impact on their stability and possibly on physiological effects. Furthermore, we provide novel evidence that these proteins are involved in UPR-induced ER protein reflux.
- Impaired vascular smooth muscle cell force-generating capacity and phenotypic deregulation in Marfan Syndrome mice(2020) NOLASCO, Patricia; FERNANDES, Carolina Goncalves; RIBEIRO-SILVA, Joao Carlos; OLIVEIRA, Percillia V. S.; SACRINI, Mariana; BRITO, Isis Vasconcelos de; BESSA, Tiphany Coralie De; PEREIRA, Lygia V.; TANAKA, Leonardo Y.; ALENCAR, Adriano; LAURINDO, Francisco Rafael MartinsMechanisms whereby fibrillin-1 mutations determine thoracic aorta aneurysms/dissections (TAAD) in Marfan Syndrome (MFS) are unclear. Most aortic aneurysms evolve from mechanosignaling deregulation, converging to impaired vascular smooth muscle cell (VSMC) force-generating capacity accompanied by synthetic phenotype switch. However, little is known on VSMC mechanoresponses in MFS pathophysiology. Here, we investigated traction force-generating capacity in aortic VSMC cultured from 3-month old mg Delta(lpn) MFS mice, together with morpho-functional and proteomic data. Cultured MFS-VSMC depicted marked phenotype changes vs. wild-type (WT) VSMC, with overexpressed cell proliferation markers but either lower (calponin-1) or higher (SM alphaactin and SM22) differentiation marker expression. In parallel, the increased cell area and its complex non-fusiform shape suggested possible transition towards a mesenchymal-like phenotype, confirmed through several markers (e.g. N-cadherin, Slug). MFS-VSMC proteomic profile diverged from that of WT-VSMC particularly regarding lower expression of actin cytoskeleton-regulatory proteins. Accordingly, MFS-VSMC displayed lower traction force-generating capacity and impaired contractile moment at physiological substrate stiffness, and markedly attenuated traction force responses to enhanced substrate rigidity. Such impaired mechanoresponses correlated with decreased number, altered morphology and delocalization of focal adhesions, as well as dis-organized actin stress fiber network vs. WT-VSMC. In VSMC cultured from 6-month-old mice, phenotype changes were attenuated and both WT-VSMC and MFS-VSMC generated less traction force, presumably involving VSMC aging, but without evident senescence. In summary, MFS-VSMC display impaired force-generating capacity accompanying a mesenchymal-like phenotype switch connected to impaired cytoskeleton/focal adhesion organization. Thus, MFS-associated TAAD involves mechanoresponse impairment common to other TAAD types, but through distinct mechanisms.