THAIS MARTINS DE LIMA
Projetos de Pesquisa
Unidades Organizacionais
LIM/51 - Laboratório de Emergências Clínicas, Hospital das Clínicas, Faculdade de Medicina
LIM/02 - Laboratório de Anatomia Médico-Cirúrgica, Hospital das Clínicas, Faculdade de Medicina
LIM/02 - Laboratório de Anatomia Médico-Cirúrgica, Hospital das Clínicas, Faculdade de Medicina
3 resultados
Resultados de Busca
Agora exibindo 1 - 3 de 3
- The role of nitric oxide in the epigenetic regulation of THP-1 induced by lipopolysaccharide(2016) RIOS, Ester Correia Sarmento; LIMA, Thais Martins de; MORETTI, Ana Iochabel Soares; SORIANO, Francisco GarciaAims: Changes in the gene expression are one of the molecular events involved in the Systemic of Inflammatory Response Syndrome during sepsis. The preconditioning with low doses of lipopolysaccharide (LPS) reduces the expression of pro-inflammatory genes leading to less tissue damage and better outcome. This hyporesponsive state called tolerance is associated to alterations in chromatin structure and nitric oxide (NO) production. In the current study, we demonstrated that tolerance induced by LPS was found to be NO-dependent and related to epigenetic changes. Main methods: THP-1 cells were cultivated in RPMI medium(Control), submitted to tolerance (500 ng/mL of LPS 24 h before challenge with 1000 ng/mL of LPS during 24 h Tolerant group) and challenge (1000 ng/mL of LPS during 24 h Directly challenged group). The analyses performed were: cytokines production, histone acetyl transferases/histone deacetylases (HAT/HDAC) activity, nitrosylation of HDAC-2 and -3, expression of acetylated histones H3 and H4. HDAC and Nitric Oxide Synthases (NOS) activities were inhibited with 30 mM trichostatin (TSA) and 100 mu M LNAME, respectively. Key findings: Administration of low doses of LPS repressed the production of IL-6 and IL-10, however this effect was abolished with the inhibition of NOS activity and by TSA in the case of IL-10. Tolerance modulates the activity of HAT and, consequently, the acetylation of histones H3 and H4. Inhibition of NO decreases acetylation of Histones. The HDACs 2 and 3 were nitrosylated after the tolerance induction. Significance: The tolerance to LPS regulates the cytokine production by modulating chromatin structure and this event is NO dependent.
- The mechanisms involved in the increased adiposity induced by interruption of regular physical exercise practice(2019) SERTIE, Rogerio A. L.; CURI, Rui; OLIVEIRA, Ariclecio C.; ANDREOTTI, Sandra; CAMINHOTTO, Rennan O.; LIMA, Thais Martins de; PROENCA, Andre R. G.; REIS, Gabriela B.; LIMA, Fabio B.Aims: We investigated the effects of physical detraining on lipogenesis/lipolysis and cellularity (apoptosis/adipogenesis) in rat subcutaneous (inguinal; SC) and visceral (retroperitoneal; RP) white adipose depots. Main methods: Three groups of male Wistar rats (6-wk old) were studied: (1) (T) trained for 12 weeks; (2) (D) trained for 8 weeks and detrained for 4 weeks; and (3) (S) age-matched sedentary. Training consisted of treadmill running sessions (1 h/day, 5 days/week, 50-60% maximal race capacity). Key findings: Physical detraining increased glucose oxidation, lipogenesis, and adipocyte size in the SC and RP depots. The number of apoptotic SC adipocytes was reduced by 53% in the T (p < 0.0001) and by 43% in the D (p < 0.001) as compared with S. RP adipocyte apoptosis in the T and D was 9.48% and 10.9% greater compared to the S, respectively (p < 0.05). In the SC stromal vascular fraction (SVF) of D rats, adiponectin, sterol regulatory element binding protein (SREBP)-1c, Peroxisome proliferator-activated receptor gamma (PPAR.), and Perilipin A mRNA expressions were more pronounced than S group, suggesting a more intense adipogenesis. This putative adipogenic effect was not observed in the RP depot. The physical detraining promoted rapid increase in the SC and RP depots however not through the same mechanisms. Significance: Physical detraining induced fat cell hypertrophy (increase of lipogenesis) in both SC and RP whereas hyperplasia (increase of adipogenesis and reduction of apoptosis) was found in SC only. These results indicate the mechanism associated with obesogenic effects of detraining varies with the fat depot.
- Preventive and therapeutic moderate aerobic exercise programs convert atherosclerotic plaques into a more stable phenotype(2016) CARDINOT, Themis M.; LIMA, Thais M.; MORETTI, Ana I. S.; KOIKE, Marcia K.; NUNES, Valeria S.; CAZITA, Patricia M.; KRIEGER, Marta H.; BRUM, Patricia C.; SOUZA, Heraldo P.The mechanisms by which exercise affects atherosclerotic plaque stability remain incompletely understood. We evaluated the effects of two training protocols on both atherosclerotic plaque structure and the signaling pathways involved in plaque rupture. Methods: Male low-density lipoprotein (LDL) receptor knockout mice were fed a high-fat, high-cholesterol diet (HFD). One group was subjected to moderate exercise using a treadmill for 14 weeks (preventive protocol). The other group started an exercise regimen after 16 weeks of the HFD (therapeutic group). Atherosclerotic plaques within the aorta were evaluated for lipid and collagen contents, as well as for inflammatory markers. Plasma cholesterol and cytokine levels were also determined. Results: The mice receiving a HFD developed hypercholesterolemia and atherosclerotic plaques within the aorta. The aortas from the animals in the preventive protocol exhibited smaller lipid cores and higher collagen content. These animals also exhibited lower CD40 expression within the plaques. The aortas of the mice in the therapeutic group exhibited higher collagen content, but no differences in either lipid core size or plaque size were noted. No differences in blood pressure, plasma cholesterol, cytokine levels, plaque size or metalloproteinase 9 expression were observed in the trained animals compared with the sedentary animals. Conclusion: Moderate aerobic exercise modified atherosclerotic plaque characteristics and converted the plaques into a more stable phenotype, increasing the collagen content in response to both exercise programs. Furthermore, moderate aerobic exercise reduced the animals' fat content and decreased the activity of the CD40-CD40L signaling pathway in the preventive group.