Protective effect of resveratrol against caspase 3 activation in primary mouse fibroblasts.

AIM: To study the effect of resveratrol on survival and caspase 3 activation in non-transformed cells after serum deprivation. METHODS: Apoptosis was induced by serum deprivation in primary mouse embryonic fibroblasts. Caspase 3 activation and lactate dehydrogenase release were assayed as cell viability measure by using their fluorogenic substrates. The involvement of PI3K, ERK, JNK, p38, and SIRT1 signaling pathways was also examined. RESULTS: Serum deprivation of primary fibroblasts induced significant activation of caspase 3 within 3 hours and reduced cell viability after 24 hours. Resveratrol dose-dependently prevented caspase activation and improved cell viability with 50% inhibitory concentration (IC50)=66.3+/-13.81 muM. It also reduced the already up-regulated caspase 3 activity when it was added to the cell culture medium after 3 hour serum deprivation, suggesting its rescue effect. Among the major signaling pathways, p38 kinase was critical for the protective effect of resveratrol which was abolished completely in the presence of p38 inhibitor. CONCLUSION: Resveratrol showed protective effect against cell death in a rather high dose. Involvement of p38 kinase in this effect suggests the role of mild stress in its cytoprotective action. Furthermore due to its rescue effect, resveratrol may be used not only for prevention, but also treatment of age-related degenerative diseases, but in the higher dose than consumed in conventional diet

Effects of Cariprazine, Aripiprazole, and Olanzapine on Mouse Fibroblast Culture: Changes in Adiponectin Contents in Supernatants, Triglyceride Accumulation, and Peroxisome Proliferator-Activated Receptor-γ Expression

Background and Objectives: The use of the dopamine-partial agonist subclass (also termed dopamine stabilizers) of atypical antipsychotics for the treatment of negative schizophrenia symptoms and some mood disorders has increased recently. Similar to other second-generation antipsychotics (SGAs), aripiprazole (ARI) and cariprazine (CAR) also influence food intake, but the peripheral effects of these drugs on adipose−tissue homeostasis, including adipokine secretion as well as lipo- and adipogenesis, are not fully elucidated. In this study, we explored the adipocyte-related mechanisms induced by second-generation antipsychotics (SGAs), leading to changes in peripheral signals involved in energy homeostasis. Materials and Methods: CAR, a new SGA, was compared with ARI and olanzapine (OLA), using cell cultures to study adipogenesis, and the expression levels of peroxisome proliferator-activated receptor-γ (PPAR-γ) was measured in adipocytes derived from mouse fibroblasts, by western blotting on days 7, 14, and 21 postinduction. The triglyceride (TG) content of the cells was also evaluated on day 15 using Oil Red O staining, and the adiponectin (AN) content in the cell culture supernatants was quantified on days 7 and 15 by enzyme-linked immunosorbent assay. Cells were treated with two concentrations of ARI (0.5 and 20 µg/mL), OLA (1 and 20 µg/mL), and CAR (0.1 and 2 µg/mL). Results: Both concentrations of ARI and OLA, as well as the lower concentration of CAR, significantly increased the TG contents. The AN levels in the supernatants were significantly increased by the higher concentration of ARI on days 7 and 15 (p < 0.05). Although PPAR-γ levels were not significantly affected by ARI and OLA, the lower concentration of CAR induced a significant time-dependent decrease in PPAR-γ expression (p < 0.05). Conclusions: The in vitro adipogenesis considered from TG accumulation, AN secretion, and PPAR-γ expression was differently influenced by ARI, CAR, and OLA. Understanding the adipocyte-related mechanisms of antipsychotics could contribute to understanding their weight-influencing effect

The role of autophagy induction in the mechanism of cytoprotective effect of resveratrol.

We aimed at studying the potential mechanisms in the preventive effect of resveratrol on serum deprivation induced caspase 3 activation on non-transformed cells. METHODS: Apoptosis was induced by serum deprivation in primary mouse embryonic fibroblasts. Caspase 3 activation, reactive oxygen species production and depolarization of the mitochondrial membrane were measured by fluorescence methods. The involvement of intracellular receptors and autophagy in the effect of resveratrol were analyzed by using specific agonists and antagonists. The role of autophagy was further examined by Western Blot analysis of its protein markers, LC3-II and p62 as well as by acridine orange staining of acidic vacuoles. RESULTS: We found that neither aromatic hydrocarbon receptors nor estrogen receptors play an important role in the cytoprotective effect of resveratrol. Reactive oxygen species production was not significantly altered by either serum deprivation or resveratrol treatment. In the presence of serum deprivation resveratrol however, induced a significant depolarization in mitochondrial membrane potential. The autophagy inhibitor, chloroquine not only eliminated the preventive effect of resveratrol, but also turned it to deleterious suggesting the prominent role of autophagy induction in the cytoprotective effect. Resveratrol did not alter LC3-II expression, but facilitated p62 degradation in serum deprived cells, suggesting its ability to augment the late phase of autophagy and thus promote the autophagic flux. CONCLUSION: We have demonstrated that resveratrol can protect primary fibroblasts against serum deprivation induced apoptosis by provoking mild mitochondrial stress and consequent up-regulation of autophagic flux

Characterization of a Cell Line Model for d-Serine Uptake.

d-Serine is an important co-agonist of the N-methyl-d-aspartate (NMDA) receptors in the brain and its altered activity was identified in various pathological conditions. Modification of the extracellular d-serine level is suggested to be able to modulate the receptor function. Its transporters may thus serve as potential drug targets. The aim of this work was to find an easily available human cell line model appropriate for screening molecules affecting d-serine transporters. Characteristics of d-serine transport into SH-SY5Y human neuroblastoma cell line were studied and compared to those in cultured primary astrocytes. Uptake was followed by measuring intracellular d-serine concentration by capillary electrophoresis with laser induced fluorescence detection method. We found that SH-SY5Y cells express functional ASCT-1 and ASCT-2 neutral amino acid transporters and show similar d-serine uptake kinetics to cultured astrocytes. Neutral amino acids inhibited d-serine uptake similarly in both cell types. Complete inhibition was achieved by l-alanine and l-threonine alike, while the two-step inhibition curve of trans-hydroxy-l-proline, a selective inhibitor of ASCT-1 supported the presence of functioning ASCT-1 and ASCT-2 transporters. Its higher affinity step corresponding to inhibition of ASCT-1 was responsible for about 30% of the total d-serine uptake. Based on our results human SH-SY5Y cell line shows similar uptake characteristics to primary astrocytes and thus can serve as a suitable model system for testing of compounds for influencing d-serine uptake into astrocytes

High Fat High Sucrose Diet Modifies Uterine Contractility and Cervical Resistance in Pregnant Rats: The Roles of Sex Hormones, Adipokines and Cytokines

Background: In obesity, the adipose tissue becomes a very significant endocrine organ producing different factors called adipokines, such as leptin, adiponectin and kisspeptin; however, no data are available about their actions on uterine contraction in obese pregnant rats. Our aim was to study the impact of obesity on pregnant uterine contraction in a rat model. Methods: Obesity was induced by the consumption of a high fat high sucrose diet (HFHSD) for 9 weeks, including pregnancy. Glucose tolerance, sex hormone, cytokine and adipokine levels were measured. Uterine contractions and cervical resistance, as well as their responses to adipokines, were tested along with the expressions of their uterine receptors. Results: HFHSD increased body weight, and altered glucose tolerance and fat composition. The uterine leptin and kisspeptin pathway affect increased. The levels of proinflammatory cytokines were reduced, while the plasma level of progesterone was increased, resulting in weaker uterine contractions, and improving the uterine relaxing effects of adipokines. HFHSD reduced cervical resistance, but the core effect of adipokines is difficult to determine. Conclusions: Obesity in pregnant rats reduces uterine contractility and cytokine-induced inflammatory processes, and therefore obese pregnant rat methods are partially applicable for modelling human processes