RESUMEN
SCOPE: Obesity and insulin resistance constitute risk factors for the development of tauopathies and other neurodegenerative diseases. (Poly)phenol compounds are under study for its role in protecting effects against neural injuries and degeneration. Here, we investigated the effect of Amazonian açai pulp (AP) intake in the prevention of memory and cognitive impairment resulting from a high-fat diet intake in mice. METHODS AND RESULTS: Obesity and insulin resistance was induced with a high-fat diet and supplemented with 2% AP to investigate peripheral insulin resistance, recognition memory and tau protein stability via AKT/GSK3-ß signaling pathway. The consumption of AP for 70 days improved peripheral insulin sensitivity and phosphorylation of AKT/GSK3-ß in mice hippocampi. The animals fed high-fat diets supplemented with AP showed better performance in the novel object recognition test (NOR) in comparison to the H group. Catalase activity and reduced glutathione (GSH) values were improved in the treated mice. CONCLUSIONS: These results suggest that the supplementation of AP can attenuate the effects of high-fat diet consumption in peripheral insulin resistance and improve cognitive behavior.
Asunto(s)
Resistencia a la Insulina , Ratones , Animales , Ratones Obesos , Proteínas Proto-Oncogénicas c-akt , Glucógeno Sintasa Quinasa 3/farmacología , Cognición , Obesidad/metabolismo , Insulina/metabolismo , Dieta Alta en Grasa , Ratones Endogámicos C57BLRESUMEN
This study aimed to investigate whether GSK-3 inhibition (CHIR99021) effectively promoted mineralization by cementoblasts (OCCM-30). OCCM-30 cells were used and treated with different concentrations of CHIR99021 (2.5, 5, and 10 mM). Experiments included proliferation and viability, cellular metabolic activity, gene expression, and mineral nodule formation by Xylene Orange at the experimental time points. In general, CHIR99021 did not significantly affect OCCM-30 viability and cell metabolism (MTT assay) (p > 0.05), but increased OCCM-30 proliferation at 2.5 mM on days 2 and 4 (p < 0.05). Data analysis further showed that inhibition of GSK-3 resulted in increased transcript levels of Axin2 in OCCM-30 cells starting as early as 4 h, and regulated the expression of key bone markers including alkaline phosphatase (Alp), runt-related transcription factor 2 (Runx-2), osteocalcin (Ocn), and osterix (Osx). In addition, CHIR99021 led to an enhanced mineral nodule formation in vitro under both osteogenic and non-osteogenic conditions as early as 5 days after treatment. Altogether, the results of the current study suggest that inhibition of GSK-3 has the potential to promote cementoblast differentiation leading to increased mineral deposition in vitro.
Asunto(s)
Cemento Dental , Glucógeno Sintasa Quinasa 3 , Glucógeno Sintasa Quinasa 3/metabolismo , Glucógeno Sintasa Quinasa 3/farmacología , Proliferación Celular , Osteocalcina/análisis , Diferenciación Celular/fisiologíaRESUMEN
BACKGROUND/AIM: Prostate cancer (PCa) is one of the most common malignancies in adult men. LQB-118 is a pterocarpanquinone with antitumor activity toward prostate cancer cells. It inhibits cell proliferation by down-regulating cyclins D1 and B1 and up-regulating p21. However, the effects of LQB-118 on PCa cell migration are still unclear. Herein, the LQB-118 effects on PCa metastatic cell migration/invasion and its mechanism of action were evaluated. MATERIALS AND METHODS: PC3 cells were treated with LQB-118 or Paclitaxel (PTX), and cell migration (wound healing and Boyden chamber assays) and invasion (matrigel assay) were determined. The LQB-118 mechanisms were evaluated by αVßIII protein expression (flow cytometry), protein phosphorylation (Western blot), and mRNA expression (qPCR). RESULTS: LQB-118 impaired PCa cell migration and invasion, down-regulated Akt phosphorylation, and also reduced GSK3ß phosphorylation, through a FAK-independent pathway. Also, it was observed that LQB-118 controlled the invasiveness behavior by reducing matrix metalloproteinase-9 (MMP-9) and up-regulating reversion-inducing cysteine rich protein with Kazal motifs (Reck) mRNA levels. Interestingly, LQB-118 increased integrin αvßIII expression, but this effect was not related to its activation, since the cell adhesion ability was reduced after LQB-118 treatment. CONCLUSION: These data highlight novel LQB-118 mechanisms in prostate cancer cells. LQB-118 acts as a negative regulator of the Akt/GSK3 signaling pathway and can modulate PCa cell proliferation, death, and migration/invasion. The results also support the use of LQB-118 for the treatment of metastatic PCa, alone or combined with another chemotherapeutic agent, due to its demonstrated pleiotropic activities.
Asunto(s)
Metaloproteinasa 9 de la Matriz , Neoplasias de la Próstata , Humanos , Masculino , Línea Celular Tumoral/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Expresión Génica , Glucógeno Sintasa Quinasa 3/genética , Glucógeno Sintasa Quinasa 3/farmacología , Glucógeno Sintasa Quinasa 3/uso terapéutico , Glucógeno Sintasa Quinasa 3 beta/efectos de los fármacos , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Proteínas Ligadas a GPI/efectos de los fármacos , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/metabolismo , Metaloproteinasa 9 de la Matriz/efectos de los fármacos , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/metabolismo , Invasividad Neoplásica , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Proteínas Proto-Oncogénicas c-akt/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN MensajeroRESUMEN
The possibility that glycogen synthase kinase 3 (GSK3) could modulate α1A-adrenergic receptor (α1A-AR) function and regulation was tested employing LNCaP and HEK293 cells transfected to express the enhanced green fluorescent protein-tagged human α1A-AR. Receptor phosphorylation and internalization, intracellular free calcium, α1A-AR-GSK3 colocalization, and coimmunoprecipitation were studied. The effects of the pharmacological GSK3 inhibitor, SB-216763, and the coexpression of a dominant-negative mutant of this kinase, as well as the signaling, desensitization, and internalization of receptors with S229, S258, S352, and S381 substitutions for alanine or aspartate, were also determined. SB-216763 inhibited agonist- and phorbol myristate acetate (PMA)-mediated α1A-AR phosphorylation, reduced oxymetazoline-induced desensitization, and magnified that induced by PMA. Agonists and PMA increased receptor-GSK3 colocalization and coimmunoprecipitation. Expression of a dominant-negative GSK3 mutant reduced agonist- but not PMA-induced receptor internalization. α1A-AR with the GSK3 putative target sites mutated to alanine exhibited reduced phosphorylation and internalization in response to agonists and increased PMA-induced desensitization. Agonist-induced, but not PMA-induced, receptor-ß arrestin intracellular colocalization was diminished in cells expressing the GSK3 putative target sites mutated to alanine. Our data indicated that GSK3 exerts a dual action on α1A-AR participating in agonist-mediated desensitization and internalization and avoiding PMA-induced desensitization.