Switching to moclobemide to reverse fluoxetine-induced sexual dysfunction in patients with depression.

PubMed Central

Ramasubbu, R

1999-01-01

OBJECTIVE: To determine the efficacy of substituting moclobemide, a reversible monoamine oxidase-A inhibitor, for fluoxetine to reverse fluoxetine-induced sexual dysfunction in patients with depression. DESIGN: Prospective open trial. SETTING: Outpatient treatment. PARTICIPANTS: Five patients with depressive disorder who experienced sexual side effects during treatment with standard doses of fluoxetine (20 to 40 mg per day). INTERVENTION: Discontinuation of fluoxetine and replacement with moclobemide (300 to 600 mg per day) after a 2-week washout period. OUTCOME MEASURES: Libido, orgasmic function (in women) or erectile and ejaculatory function (in men), and overall improvement in sexual function during a follow-up period of 2 months to 3 years. RESULTS: Among patients receiving fluoxetine questioned about sexual side effects, 4 (1 man and 3 women) had treatment-related diminished libido with poor orgasmic response or partial erectile failure, and 1 female patient had enhanced sexual desire with intense clitoral stimulation. In all patients, sexual disturbances resolved completely after a 2-week washout period and a switch to treatment with moclobemide. Moclobemide was well tolerated. The antidepressant effect of moclobemide was comparable to that of fluoxetine. CONCLUSIONS: Moclobemide may be preferred as a treatment for depression in patients with fluoxetine-induced sexual dysfunction. PMID:9987207

Effects of moderate treadmill exercise and fluoxetine on behavioural and cognitive deficits, hypothalamic-pituitary-adrenal axis dysfunction and alternations in hippocampal BDNF and mRNA expression of apoptosis - related proteins in a rat model of post-traumatic stress disorder.

PubMed

Shafia, Sakineh; Vafaei, Abbas Ali; Samaei, Seyed Afshin; Bandegi, Ahmad Reza; Rafiei, Alireza; Valadan, Reza; Hosseini-Khah, Zahra; Mohammadkhani, Raziyeh; Rashidy-Pour, Ali

2017-03-01

Post-traumatic stress disorder (PTSD) is a condition that develops after an individual has experienced a major trauma. Currently, selective serotonin reuptake inhibitors (SSRIs) like fluoxetine are the first-line choice in PTSD drug treatment but their moderate response rates and side effects indicate an urgent need for the development of new treatment. Physical activity is known to improve symptoms of certain neuropsychiatric disorders. The present study investigated the effects of moderate treadmill exercise, the antidepressant fluoxetine and the combined treatment on behavioural deficits, and hypothalamic-pituitary-adrenal (HPA) axis dysfunction. We also examined alternations in hippocampal brain-derived neurotrophic factor (BDNF) and mRNA expression of apoptosis - related proteins in a rat model of PTSD: the single prolonged stress (SPS) model. Rats were exposed to SPS (restraint for 2h, forced swimming for 20min and ether anaesthesia) and were then kept undisturbed for 14days. After that, SPS rats were subjected to chronic treatment with fluoxetine (10mg/kg/day, for 4weeks), moderate treadmill running (4weeks, 5day per week) and the combined treatment (fluoxetine plus treadmill exercise), followed by behavioural, biochemical and apoptosis markers assessments. SPS rats exhibited increased anxiety levels in the elevated plus maze and light/dark box, impaired fear conditioning and extinction in inhibitory avoidance (IA) task, impaired spatial memory in a recognition location memory task and enhanced negative feedback on the HPA axis following a dexamethasone suppression test. SPS rats also showed reduced hippocampal BDNF and enhanced apoptosis. Moderate treadmill exercise, fluoxetine and the combined treatment alleviated the SPS-induced alterations in terms of anxiety levels, HPA axis inhibition, IA conditioning and extinction, hippocampal BDNF and apoptosis markers. Furthermore, the combined treatment was more effective than fluoxetine alone, but in most tests

Fluoxetine treatment ameliorates depression induced by perinatal arsenic exposure via a neurogenic mechanism

PubMed Central

Tyler, Christina R.; Solomon, Benjamin R.; Ulibarri, Adam L.; Allan, Andrea M.

2014-01-01

Several epidemiological studies have reported an association between arsenic exposure and increased rates of psychiatric disorders, including depression, in exposed populations. We have previously demonstrated that developmental exposure to low amounts of arsenic induces depression in adulthood along with several morphological and molecular aberrations, particularly associated with the hippocampus and the hypothalamic–pituitary–adrenal (HPA) axis. The extent and potential reversibility of this toxin-induced damage has not been characterized to date. In this study, we assessed the effects of fluoxetine, a selective serotonin reuptake inhibitor antidepressant, on adult animals exposed to arsenic during development. Perinatal arsenic exposure (PAE) induced depressive-like symptoms in a mild learned helplessness task and in the forced swim task after acute exposure to a predator odor (2,4,5-trimethylthiazoline, TMT). Chronic fluoxetine treatment prevented these behaviors in both tasks in arsenic-exposed animals and ameliorated arsenic-induced blunted stress responses, as measured by corticosterone (CORT) levels before and after TMT exposure. Morphologically, chronic fluoxetine treatment reversed deficits in adult hippocampal neurogenesis (AHN) after PAE, specifically differentiation and survival of neural progenitor cells. Protein expression of BDNF, CREB, the glucocorticoid receptor (GR), and HDAC2 was significantly increased in the dentate gyrus of arsenic animals after fluoxetine treatment. This study demonstrates that damage induced by perinatal arsenic exposure is reversible with chronic fluoxetine treatment resulting in restored resiliency to depression via a neurogenic mechanism. PMID:24952232

5-HT(1A) receptor antagonism reverses and prevents fluoxetine-induced sexual dysfunction in rats.

PubMed

Sukoff Rizzo, Stacey J; Pulicicchio, Claudine; Malberg, Jessica E; Andree, Terrance H; Stack, Gary P; Hughes, Zoë A; Schechter, Lee E; Rosenzweig-Lipson, Sharon

2009-09-01

Sexual dysfunction associated with antidepressant treatment continues to be a major compliance issue for antidepressant therapies. 5-HT(1A) antagonists have been suggested as beneficial adjunctive treatment in respect of antidepressant efficacy; however, the effects of 5-HT(1A) antagonism on antidepressant-induced side-effects has not been fully examined. The present study was conducted to evaluate the ability of acute or chronic treatment with 5-HT(1A) antagonists to alter chronic fluoxetine-induced impairments in sexual function. Chronic 14-d treatment with fluoxetine resulted in a marked reduction in the number of non-contact penile erections in sexually experienced male rats, relative to vehicle-treated controls. Acute administration of the 5-HT(1A) antagonist WAY-101405 resulted in a complete reversal of chronic fluoxetine-induced deficits on non-contact penile erections at doses that did not significantly alter baselines. Chronic co-administration of the 5-HT(1A) antagonists WAY-100635 or WAY-101405 with fluoxetine prevented fluoxetine-induced deficits in non-contact penile erections in sexually experienced male rats. Moreover, withdrawal of WAY-100635 from co-treatment with chonic fluoxetine, resulted in a time-dependent reinstatement of chronic fluoxetine-induced deficits in non-contact penile erections. Additionally, chronic administration of SSA-426, a molecule with dual activity as both a SSRI and 5-HT(1A) antagonist, did not produce deficits in non-contact penile erections at doses demonstrated to have antidepressant-like activity in the olfactory bulbectomy model. Taken together, these data suggest that 5-HT(1A) antagonist treatment may have utility for the management of SSRI-induced sexual dysfunction.

Fluoxetine Induces Proliferation and Inhibits Differentiation of Hypothalamic Neuroprogenitor Cells In Vitro

PubMed Central

Sousa-Ferreira, Lígia; Aveleira, Célia; Botelho, Mariana; Álvaro, Ana Rita; Pereira de Almeida, Luís; Cavadas, Cláudia

2014-01-01

A significant number of children undergo maternal exposure to antidepressants and they often present low birth weight. Therefore, it is important to understand how selective serotonin reuptake inhibitors (SSRIs) affect the development of the hypothalamus, the key center for metabolism regulation. In this study we investigated the proliferative actions of fluoxetine in fetal hypothalamic neuroprogenitor cells and demonstrate that fluoxetine induces the proliferation of these cells, as shown by increased neurospheres size and number of proliferative cells (Ki-67+ cells). Moreover, fluoxetine inhibits the differentiation of hypothalamic neuroprogenitor cells, as demonstrated by decreased number of mature neurons (Neu-N+ cells) and increased number of undifferentiated cells (SOX-2+ cells). Additionally, fluoxetine-induced proliferation and maintenance of hypothalamic neuroprogenitor cells leads to changes in the mRNA levels of appetite regulator neuropeptides, including Neuropeptide Y (NPY) and Cocaine-and-Amphetamine-Regulated-Transcript (CART). This study provides the first evidence that SSRIs affect the development of hypothalamic neuroprogenitor cells in vitro with consequent alterations on appetite neuropeptides. PMID:24598761

FLUOXETINE PREVENTS 8-OH-DPAT-INDUCED HYPERPHAGIA IN FISCHER INBRED RATS

PubMed Central

Miryala, Chandra Suma Johnson; Maswood, Navin; Uphouse, Lynda

2011-01-01

Ovariectomized, Fischer rats were hormonally primed with 10 μg estradiol benzoate and 50 μg progesterone or were treated with the sesame seed oil vehicle. Food intake was measured 2 hr and 24 hr after treatment with 0.25 mg/kg of the 5-HT1A receptor agonist, (±)-8-hydroxy 2-(di-n-propylamino) tetralin (8-OH-DPAT), 5 mg/kg of the selective serotonin reuptake inhibitor, fluoxetine, or their combination. Consistent with prior studies, two hr food intake of rats given fluoxetine and 8-OH-DPAT did not differ from vehicle controls. 8-OH-DPAT-induced hyperphagia, evident at 2 hr, was blocked by co-treatment with fluoxetine. However, in contrast to prior studies, 5 mg/kg fluoxetine, alone, had only modest effects on food intake. Differences in our experimental protocols and/or the strain of rat may account for the lower anorectic response to fluoxetine. Nevertheless, the absence of a significant response to fluoxetine, alone, coupled with the drug's attenuation of the hyperphagic effect of 8-OH-DPAT, leads to the suggestion that the behavioral response to the combined treatment is more complex than that of simple additivity. Consistent with this suggestion, 24 hr food intake of rats given 8-OH-DPAT and fluoxetine was lower than that of vehicle or 8-OH-DPAT-treated rats. PMID:21281662

Fluoxetine prevents 8-OH-DPAT-induced hyperphagia in Fischer inbred rats.

PubMed

Miryala, Chandra Suma Johnson; Maswood, Navin; Uphouse, Lynda

2011-04-01

Ovariectomized, Fischer rats were hormonally primed with 10 μg estradiol benzoate and 50 μg progesterone or were treated with the sesame seed oil vehicle. Food intake was measured 2 h and 24 h after treatment with 0.25 mg/kg of the 5-HT(1A) receptor agonist, (±)-8-hydroxy 2-(di-n-propylamino) tetralin (8-OH-DPAT), 5 mg/kg of the selective serotonin reuptake inhibitor, fluoxetine, or their combination. Consistent with prior studies, two hour food intake of rats given fluoxetine and 8-OH-DPAT did not differ from vehicle controls. 8-OH-DPAT-induced hyperphagia, evident at 2 h, was blocked by co-treatment with fluoxetine. However, in contrast to prior studies, 5 mg/kg fluoxetine, alone, had only modest effects on food intake. Differences in our experimental protocols and/or the strain of rat may account for the lower anorectic response to fluoxetine. Nevertheless, the absence of a significant response to fluoxetine, alone, coupled with the drug's attenuation of the hyperphagic effect of 8-OH-DPAT, leads to the suggestion that the behavioral response to the combined treatment is more complex than that of simple additivity. Consistent with this suggestion, 24 h food intake of rats given 8-OH-DPAT and fluoxetine was lower than that of vehicle or 8-OH-DPAT-treated rats. Copyright © 2011 Elsevier Inc. All rights reserved.

Effects of ketamine and N-methyl-D-aspartate on fluoxetine-induced antidepressant-related behavior using the forced swimming test.

PubMed

Owolabi, Rotimi Adegbenga; Akanmu, Moses Atanda; Adeyemi, Oluwole Isaac

2014-04-30

This study investigated the effects of ketamine on fluoxetine-induced antidepressant behavior using the forced swimming test (FST) in mice. In order to understand the possible role of N-methyl-d-aspartate (NMDA) neurotransmission in the antidepressant effect of fluoxetine, different groups of mice (n=10) were administered with acute ketamine (3mg/kg, i.p.), acute NMDA (75mg/kg and 150mg/kg, i.p.) and a 21-day chronic ketamine (15mg/kg, i.p./day) were administered prior to the administration of fluoxetine (20mg/kg, i.p.) in the mice. Antidepressant related behavior (immobility score) was measured using the forced swimming test. The results showed that the acute ketamine and fluoxetine alone treatments elicited a significant (p<0.05) reduction in immobility score compared with saline control. Furthermore, pre-treatment with acute ketamine significantly enhanced by the fluoxetine-induced decrease in immobility score. In contrast, pre-treatment with NMDA (150mg/kg) significantly (p<0.05) reversed fluoxetine-induced decrease in immobility score. On the other hand, chronic administration of ketamine significantly elicited an increase in immobility score as well as reversed the reduction induced by fluoxetine. Similarly, NMDA administration at both 75mg/kg and 150mg/kg increased immobility score in chronically administered ketamine groups. Furthermore, chronic administration of ketamine, followed by NMDA (75mg/kg) and fluoxetine significantly elevated the immobility score when compared with the group that received NMDA and fluoxetine but not chronically treated with ketamine. It can be suggested) that facilitation of NMDA transmission blocked fluoxetine-induced reduction in immobility score, while down-regulation of NMDA transmission is associated with increase in fluoxetine-induced antidepressant-related behavior in mice. Down-regulation of the NMDA transmission is proposed as an essential component of mechanism of suppression of depression related behaviors by

Fluoxetine potentiates methylphenidate-induced gene regulation in addiction-related brain regions: Concerns for use of cognitive enhancers?

PubMed Central

Steiner, Heinz; Van Waes, Vincent; Marinelli, Michela

2009-01-01

Background There is growing use of psychostimulant cognitive enhancers such as methylphenidate (Ritalin). Methylphenidate differs from the psychostimulant cocaine because it does not enhance brain levels of serotonin. We investigated whether exposure to methylphenidate combined with a serotonin-enhancing medication, the prototypical selective serotonin reuptake inhibitor (SSRI) fluoxetine (Prozac), would produce more “cocaine-like” molecular and behavioral changes. Methods We measured the effects of fluoxetine on gene expression induced by the cognitive enhancer methylphenidate in the striatum and nucleus accumbens of rats, by in situ hybridization histochemistry. We also determined whether fluoxetine modified behavioral effects of methylphenidate. Results Fluoxetine robustly potentiated methylphenidate-induced expression of the transcription factors c-fos and zif 268 throughout the striatum and to some degree in the nucleus accumbens. Fluoxetine also enhanced methylphenidate-induced stereotypical behavior. Conclusions Both potentiated gene regulation in the striatum and the behavioral effects indicate that combining the SSRI fluoxetine with the cognitive enhancer methylphenidate mimics cocaine effects, consistent with an increased risk for substance use disorder. PMID:19931852

Protective Effects of Caffeic Acid Phenethyl Ester on Fluoxetine-Induced Hepatotoxicity: An Experimental Study.

PubMed

Yılmaz, Ahmet; Elbey, Bilal; Yazgan, Ümit Can; Dönder, Ahmet; Arslan, Necmi; Arslan, Serkan; Alabalık, Ulaş; Aslanhan, Hamza

2016-01-01

Background. The aim of the study was to analyse the effect of caffeic acid phenethyl ester (CAPE) on fluoxetine-induced hepatotoxicity in rats. Materials and Methods. Group I served as control. Group II received CAPE intraperitoneally. Group III received fluoxetine per orally. Group IV received fluoxetine and CAPE. The total antioxidant capacity (TAC), total oxidant status (TOS), oxidative stress index (OSI), and liver enzymes including paraoxonase-1 (PON-1), aspartate transaminase, and alanine transaminase levels were measured. Liver tissues were processed histopathologically for evaluation of liver injury and to validate the serum enzyme levels. Results. An increase in TOS and OSI and a decrease in TAC and PON-1 levels in serum and liver tissues of Group III were observed compared to Groups I and II. After treatment with CAPE, the level of TOS and OSI decreased while TAC and PON-1 increased in serum and liver in Group IV. Histopathological examination of the liver revealed hepatic injury after fluoxetine treatment and reduction of injury with CAPE treatment. Conclusion. Our results suggested that CAPE treatment provided protection against fluoxetine toxicity. Following CAPE treatment with fluoxetine-induced hepatotoxicity, TOS and OSI levels decreased, whereas PON-1 and TAC increased in the serum and liver.

Involvement of PI3K/Akt/FoxO3a and PKA/CREB Signaling Pathways in the Protective Effect of Fluoxetine Against Corticosterone-Induced Cytotoxicity in PC12 Cells.

PubMed

Zeng, Bingqing; Li, Yiwen; Niu, Bo; Wang, Xinyi; Cheng, Yufang; Zhou, Zhongzhen; You, Tingting; Liu, Yonggang; Wang, Haitao; Xu, Jiangping

2016-08-01

The selective serotonin reuptake inhibitor fluoxetine is neuroprotective in several brain injury models. It is commonly used to treat major depressive disorder and related conditions, but its mechanism of action remains incompletely understood. Activation of the phosphatidylinositol-3-kinase/protein kinase B/forkhead box O3a (PI3K/Akt/FoxO3a) and protein kinase A/cAMP-response element binding protein (PKA/CREB) signaling pathways has been strongly implicated in the pathogenesis of depression and might be the downstream target of fluoxetine. Here, we used PC12 cells exposed to corticosterone (CORT) to study the neuroprotective effects of fluoxetine and the involvement of the PI3K/Akt/FoxO3a and PKA/CREB signaling pathways. Our results show that CORT reduced PC12 cells viability by 70 %, and that fluoxetine showed a concentration-dependent neuroprotective effect. Neuroprotective effects of fluoxetine were abolished by inhibition of PI3K, Akt, and PKA using LY294002, KRX-0401, and H89, respectively. Treatment of PC12 cells with fluoxetine resulted in increased phosphorylation of Akt, FoxO3a, and CREB. Fluoxetine also dose-dependently rescued the phosphorylation levels of Akt, FoxO3a, and CREB, following administration of CORT (from 99 to 110, 56 to 170, 80 to 170 %, respectively). In addition, inhibition of PKA and PI3K/Akt resulted in decreased levels of p-CREB, p-Akt, and p-FoxO3a in the presence of fluoxetine. Furthermore, fluoxetine reversed CORT-induced upregulation of p53-upregulated modulator of apoptosis (Puma) and Bcl-2-interacting mediator of cell death (Bim) via the PI3K/Akt/FoxO3a signaling pathway. H89 treatment reversed the effect of fluoxetine on the mRNA level of brain-derived neurotrophic factor, which was decreased in the presence of CORT. Our data indicate that fluoxetine elicited neuroprotection toward CORT-induced cell death that involves dual regulation from PI3K/Akt/FoxO3a and PKA/CREB pathways.

Serotonin and histamine mediate gastroprotective effect of fluoxetine against experimentally-induced ulcers in rats.

PubMed

Salem Sokar, Samia; Elsayed Elsayad, Mageda; Sabri Ali, Hend

2016-09-01

Research in the treatment of gastric ulcer has involved the investigation of new alternatives, such as anti-depressant drugs. The present study was designed to investigate the gastroprotective effects of fluoxetine against indomethacin and alcohol induced gastric ulcers in rats and the potential mechanisms of that effect. Fluoxetine (20 mg/kg) was administered IP for 14 days. For comparative purposes, other rats were treated with ranitidine (30 mg/kg). Thereafter, after 24 h of fasting, INDO (100 mg/kg) or absolute alcohol (5 ml/kg) was administered to all rats (saline was administered to naïve controls) and rats in each group were sacrificed 5 h (for INDO rats) or 1 h (for alcohol rats) later. Macroscopic examination revealed that both fluoxetine and ranitidine decreased ulcer scores in variable ratios, which was supported by microscopic histopathological examination. Biochemical analysis of fluoxetine- or ranitidine-pre-treated host tissues demonstrated reductions in tumor necrosis factor (TNF)-α and myeloperoxidase (MPO) levels and concomitant increases in gastric pH, nitric oxide (NO) and reduced glutathione (GSH) contents. Fluoxetine, more than ranitidine, also resulted in serotonin and histamine levels nearest to control values. Moreover, immuno-histochemical analysis showed that fluoxetine markedly enhanced expression of cyclo-oxygenases COX-1 and COX-2 in both models; in comparison, ranitidine did not affect COX-1 expression in either ulcer model but caused moderate increases in COX-2 expression in INDO-induced hosts and high expression in alcohol-induced hosts. The results here indicated fluoxetine exhibited better gastroprotective effects than ranitidine and this could be due to anti-secretory, anti-oxidant, anti-inflammatory and anti-histaminic effects of the drug, as well as a stabilization of gastric serotonin levels.

Anti-inflammatory and ameliorative effects of gallic acid on fluoxetine-induced oxidative stress and liver damage in rats.

PubMed

Karimi-Khouzani, Omid; Heidarian, Esfandiar; Amini, Sayed Asadollah

2017-08-01

Fluoxetine-induced liver damage is a cause of chronic liver disease. In the present study the hepatoprotective effects of gallic acid against fluoxetine-induced liver damage were examined. Forty-eight male rats were divided into six groups as follow: group 1, the control group; group 2, rats receiving fluoxetine (24mg/kg bw daily, po) without treatment; group 3, rats receiving 24mg/kg bw fluoxetine, treated with 50mg/kg bw silymarin and groups 4, 5, and 6 in which gallic acid (50, 100, and 200mg/kg bw, po, respectively) was prescribed after the consumption of fluoxetine. The histopathological changes of hepatic tissues were checked out. Fluoxetine caused a significant increase in the levels of serum glutamate oxaloacetate transaminase (GOT), serum glutamate pyruvate transaminase (GPT), lipid profiles, urea, fasting blood sugar (FBS), creatinine (Cr), protein carbonyl (PC) content, malondialdehyde (MDA), and liver TNF-α as an inflammatory element. Also, the obtained results of group 2 revealed a significant decline in ferric reducing ability of plasma (FRAP), liver catalase (CAT), superoxide dismutase (SOD), and vitamin C levels. The treatment with gallic acid showed significant ameliorations in abnormalities of fluoxetine-induced liver injury as represented by the improvement of hepatic CAT, SOD activities, vitamin C levels, serum biochemical parameters, and histopathological changes, in addition to the recovery of antioxidant defense system status. Gallic acid has inhibitory effects on fluoxetine-induced liver damage. The effect of gallic acid is derived from free radical scavenging properties and the anti-inflammatory effect related to TNF-α. Copyright © 2017. Published by Elsevier Urban & Partner Sp. z o.o.

Fluoxetine reverses the behavioral despair induced by neurogenic stress in mice: role of N-methyl-d-aspartate and opioid receptors.

PubMed

Haj-Mirzaian, Arya; Kordjazy, Nastaran; Ostadhadi, Sattar; Amiri, Shayan; Haj-Mirzaian, Arvin; Dehpour, AhmadReza

2016-06-01

Opioid and N-methyl-d-aspartate (NMDA) receptors mediate different effects of fluoxetine. We investigated whether opioid and NMDA receptors are involved in the protective effect of fluoxetine against the behavioral despair induced by acute physical stress in male mice. We used the forced swimming test (FST), tail suspension test (TST), and open-field test (OFT) for behavioral evaluation. We used fluoxetine, naltrexone (opioid receptor antagonist), MK-801 (NMDA receptor antagonist), morphine (opioid receptor agonist), and NMDA (NMDA receptor agonist). Acute foot-shock stress (FSS) significantly induced behavioral despair (depressive-like) and anxiety-like behaviors in tests. Fluoxetine (5 mg/kg) reversed the depressant-like effect of FSS, but it did not alter the locomotion and anxiety-like behavior in animals. Acute administration of subeffective doses of naltrexone (0.3 mg/kg) or MK-801 (0.01 mg/kg) potentiated the antidepressant-like effect of fluoxetine, while subeffective doses of morphine (1 mg/kg) and NMDA (75 mg/kg) abolished this effect of fluoxetine. Also, co-administration of subeffective doses of naltrexone (0.05 mg/kg) and MK-801 (0.003 mg/kg) with fluoxetine (1 mg/kg) induced a significant decrease in the immobility time in FST and TST. Our results showed that opioid and NMDA receptors (alone or in combination) are involved in the antidepressant-like effect of fluoxetine against physical stress.

Intrauterine and lactation exposure to fluoxetine blunted in the offspring the aortic adaptive response induced by acute restraint stress.

PubMed

Marques, Bruno V D; Higashi, Carolina M; da S Novi, Daniella R B; Zanluqui, Nagela G; Gregório, Thais F; Pinge-Filho, Phileno; Gerardin, Daniela C C; Pelosi, Gislaine G; Moreira, Estefânia G; Ceravolo, Graziela S

2017-10-15

Selective serotonin reuptake inhibitors are the most widely prescribed antidepressants to women during pregnancy. Maternal treatment with fluoxetine can expose fetuses and neonates to higher levels of serotonin that plays a role in stress response. Thus, the aim of the study was to evaluate whether maternal treatment with fluoxetine interferes with aorta reactivity of adult male offspring after acute restraint stress. Wistar rats were gavaged with fluoxetine (5mg/kg/day) or water (control) during pregnancy and lactation. The experiments were performed in adult male offspring, treated or not with reserpine (4mg/Kg, ip, 28h before the experimental protocol). Fluoxetine and control rats were submitted to a single restraint stress session (ST) for 1h. Curves to phenylephrine were performed in thoracic aorta with endothelium. Aortic nitric oxide (NOx) were evaluated by the Griess method. The aortic contraction induced by phenylephrine was similar between control and fluoxetine rats. The acute stress reduced contraction in aorta of control ST compared to control, and L-NAME equaled this response. In fluoxetine rats, ST did not change the aortic constriction. Reserpine treatment restored the vasoconstriction in control ST, but did not interfere with aortic contraction in control, fluoxetine or fluoxetine ST. The NOx concentration was higher in aortas from control ST than control rats, and reserpine reduced NOx levels of control ST. The NOx concentration was similar between fluoxetine and fluoxetine ST rats, treated or not with reserpine. In conclusion, maternal treatment with fluoxetine blunted acute restraint stress-induced NO system activation and aortic adaptation in adult offspring. Copyright © 2017 Elsevier B.V. All rights reserved.

Acute Fluoxetine Treatment Induces Slow Rolling of Leukocytes on Endothelium in Mice

PubMed Central

Herr, Nadine; Mauler, Maximilian; Witsch, Thilo; Stallmann, Daniela; Schmitt, Stefanie; Mezger, Julius; Bode, Christoph; Duerschmied, Daniel

2014-01-01

Objective Activated platelets release serotonin at sites of inflammation where it acts as inflammatory mediator and enhances recruitment of neutrophils. Chronic treatment with selective serotonin reuptake inhibitors (SSRI) depletes the serotonin storage pool in platelets, leading to reduced leukocyte recruitment in murine experiments. Here, we examined the direct and acute effects of SSRI on leukocyte recruitment in murine peritonitis. Methods C57Bl/6 and Tph1−/− (Tryptophan hydroxylase1) mice underwent acute treatment with the SSRI fluoxetine or vehicle. Serotonin concentrations were measured by ELISA. Leukocyte rolling and adhesion on endothelium was analyzed by intravital microscopy in mesentery venules with and without lipopolysaccharide challenge. Leukocyte extravasation in sterile peritonitis was measured by flow cytometry of abdominal lavage fluid. Results Plasma serotonin levels were elevated 2 hours after fluoxetine treatment (0.70±0.1 µg/ml versus 0.27±0.1, p = 0.03, n = 14), while serum serotonin did not change. Without further stimulation, acute fluoxetine treatment increased the number of rolling leukocytes (63±8 versus 165±17/0.04 mm2min−1) and decreased their velocity (61±6 versus 28±1 µm/s, both p<0.0001, n = 10). In Tph1−/− mice leukocyte rolling was not significantly influenced by acute fluoxetine treatment. Stimulation with lipopolysaccharide decreased rolling velocity and induced leukocyte adhesion, which was enhanced after fluoxetine pretreatment (27±3 versus 36±2/0.04 mm2, p = 0.008, n = 10). Leukocyte extravasation in sterile peritonitis, however, was not affected by acute fluoxetine treatment. Conclusions Acute fluoxetine treatment increased plasma serotonin concentrations and promoted leukocyte-endothelial interactions in-vivo, suggesting that serotonin is a promoter of acute inflammation. E-selectin was upregulated on endothelial cells in the presence of serotonin, possibly explaining the observed

Chronic Fluoxetine Induces the Enlargement of Perforant Path-Granule Cell Synapses in the Mouse Dentate Gyrus

PubMed Central

Kitahara, Yosuke; Ohta, Keisuke; Hasuo, Hiroshi; Shuto, Takahide; Kuroiwa, Mahomi; Sotogaku, Naoki; Togo, Akinobu; Nakamura, Kei-ichiro; Nishi, Akinori

2016-01-01

A selective serotonin reuptake inhibitor is the most commonly prescribed antidepressant for the treatment of major depression. However, the mechanisms underlying the actions of selective serotonin reuptake inhibitors are not fully understood. In the dentate gyrus, chronic fluoxetine treatment induces increased excitability of mature granule cells (GCs) as well as neurogenesis. The major input to the dentate gyrus is the perforant path axons (boutons) from the entorhinal cortex (layer II). Through voltage-sensitive dye imaging, we found that the excitatory neurotransmission of the perforant path synapse onto the GCs in the middle molecular layer of the mouse dentate gyrus (perforant path-GC synapse) is enhanced after chronic fluoxetine treatment (15 mg/kg/day, 14 days). Therefore, we further examined whether chronic fluoxetine treatment affects the morphology of the perforant path-GC synapse, using FIB/SEM (focused ion beam/scanning electron microscopy). A three-dimensional reconstruction of dendritic spines revealed the appearance of extremely large-sized spines after chronic fluoxetine treatment. The large-sized spines had a postsynaptic density with a large volume. However, chronic fluoxetine treatment did not affect spine density. The presynaptic boutons that were in contact with the large-sized spines were large in volume, and the volumes of the mitochondria and synaptic vesicles inside the boutons were correlated with the size of the boutons. Thus, the large-sized perforant path-GC synapse induced by chronic fluoxetine treatment contains synaptic components that correlate with the synapse size and that may be involved in enhanced glutamatergic neurotransmission. PMID:26788851

Fluoxetine induces input-specific hippocampal dendritic spine remodeling along the septotemporal axis in adulthood and middle age.

PubMed

McAvoy, Kathleen; Russo, Craig; Kim, Shannen; Rankin, Genelle; Sahay, Amar

2015-11-01

Fluoxetine, a selective serotonin-reuptake inhibitor (SSRI), is known to induce structural rearrangements and changes in synaptic transmission in hippocampal circuitry. In the adult hippocampus, structural changes include neurogenesis, dendritic, and axonal plasticity of pyramidal and dentate granule neurons, and dedifferentiation of dentate granule neurons. However, much less is known about how chronic fluoxetine affects these processes along the septotemporal axis and during the aging process. Importantly, studies documenting the effects of fluoxetine on density and distribution of spines along different dendritic segments of dentate granule neurons and CA1 pyramidal neurons along the septotemporal axis of hippocampus in adulthood and during aging are conspicuously absent. Here, we use a transgenic mouse line in which mature dentate granule neurons and CA1 pyramidal neurons are genetically labeled with green fluorescent protein (GFP) to investigate the effects of chronic fluoxetine treatment (18 mg/kg/day) on input-specific spine remodeling and mossy fiber structural plasticity in the dorsal and ventral hippocampus in adulthood and middle age. In addition, we examine levels of adult hippocampal neurogenesis, maturation state of dentate granule neurons, neuronal activity, and glutamic acid decarboxylase-67 expression in response to chronic fluoxetine in adulthood and middle age. Our studies reveal that while chronic fluoxetine fails to augment adult hippocampal neurogenesis in middle age, the middle-aged hippocampus retains high sensitivity to changes in the dentate gyrus (DG) such as dematuration, hypoactivation, and increased glutamic acid decarboxylase 67 (GAD67) expression. Interestingly, the middle-aged hippocampus shows greater sensitivity to fluoxetine-induced input-specific synaptic remodeling than the hippocampus in adulthood with the stratum-oriens of CA1 exhibiting heightened structural plasticity. The input-specific changes and circuit

Fluoxetine Increases Hippocampal Neurogenesis and Induces Epigenetic Factors But Does Not Improve Functional Recovery after Traumatic Brain Injury

PubMed Central

Wang, Yonggang; Neumann, Melanie; Hansen, Katharina; Hong, Shuwhey M.; Kim, Sharon; Noble-Haeusslein, Linda J.

2011-01-01

Abstract The selective serotonin reuptake inhibitor fluoxetine induces hippocampal neurogenesis, stimulates maturation and synaptic plasticity of adult hippocampal neurons, and reduces motor/sensory and memory impairments in several CNS disorders. In the setting of traumatic brain injury (TBI), its effects on neuroplasticity and function have yet to be thoroughly investigated. Here we examined the efficacy of fluoxetine after a moderate to severe TBI, produced by a controlled cortical impact. Three days after TBI or sham surgery, mice were treated with fluoxetine (10 mg/kg/d) or vehicle for 4 weeks. To evaluate the effects of fluoxetine on neuroplasticity, hippocampal neurogenesis and epigenetic modification were studied. Stereologic analysis of the dentate gyrus revealed a significant increase in doublecortin-positive cells in brain-injured animals treated with fluoxetine relative to controls, a finding consistent with enhanced hippocampal neurogenesis. Epigenetic modifications, including an increase in histone 3 acetylation and induction of methyl-CpG-binding protein, a transcription factor involved in DNA methylation, were likewise seen by immunohistochemistry and quantitative Western immunoblots, respectively, in brain-injured animals treated with fluoxetine. To determine if fluoxetine improves neurological outcomes after TBI, gait function and spatial learning and memory were assessed by the CatWalk-assisted gait test and Barnes maze test, respectively. No differences in these parameters were seen between fluoxetine- and vehicle-treated animals. Thus while fluoxetine enhanced neuroplasticity in the hippocampus after TBI, its chronic administration did not restore locomotor function or ameliorate memory deficits. PMID:21175261

Chronic administration of fluoxetine or clozapine induces oxidative stress in rat liver: a histopathological study.

PubMed

Zlatković, Jelena; Todorović, Nevena; Tomanović, Nada; Bošković, Maja; Djordjević, Snežana; Lazarević-Pašti, Tamara; Bernardi, Rick E; Djurdjević, Aleksandra; Filipović, Dragana

2014-08-01

Chronic exposure to stress contributes to the etiology of mood disorders, and the liver as a target organ of antidepressant and antipsychotic drug metabolism is vulnerable to drug-induced toxicity. We investigated the effects of chronic administration of fluoxetine (15mg/kg/day) or clozapine (20mg/kg/day) on liver injury via the measurement of liver enzymes, oxidative stress and histopathology in rats exposed to chronic social isolation (21days), an animal model of depression, and controls. The activity of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST), the liver content of carbonyl groups, malonyldialdehyde (MDA), reduced glutathione (GSH), cytosolic glutathione S-transferase (GST) and nitric oxide (NO) metabolites were determined. We also characterized nuclear factor-κB (NF-κB), cyclooxygenase-2 (COX-2) and CuZn-superoxide dismutase (CuZnSOD) protein expression as well as histopathological changes. Increased serum ALT activity in chronically-isolated and control animals treated with both drugs was found while increased AST activity was observed only in fluoxetine-treated rats (chronically-isolated and controls). Increased carbonyl content, MDA, GST activity and decreased GSH levels in drug-treated controls/chronically-isolated animals suggest a link between drugs and hepatic oxidative stress. Increased NO levels associated with NF-κB activation and the concomitant increased COX-2 expression together with compromised CuZnSOD expression in clozapine-treated chronically-isolated rats likely reinforce oxidative stress, observed by increased lipid peroxidation and GSH depletion. In contrast, fluoxetine reduced NO levels in chronically-isolated rats. Isolation induced oxidative stress but histological changes were similar to those observed in vehicle-treated controls. Chronic administration of fluoxetine in both chronically-isolated and control animals resulted in more or less normal hepatic architecture, while clozapine in both groups

Fluoxetine induces input-specific hippocampal dendritic spine remodeling along the septo-temporal axis in adulthood and middle age

PubMed Central

McAvoy, Kathleen; Russo, Craig; Kim, Shannen; Rankin, Genelle; Sahay, Amar

2015-01-01

Fluoxetine, a selective serotonin-reuptake inhibitor (SSRI), is known to induce structural rearrangements and changes in synaptic transmission in hippocampal circuitry. In the adult hippocampus, structural changes include neurogenesis, dendritic and axonal plasticity of pyramidal and dentate granule neurons, and dedifferentiation of dentate granule neurons. However, much less is known about how chronic fluoxetine affects these processes along the septo-temporal axis and during the aging process. Importantly, studies documenting the effects of fluoxetine on density and distribution of spines along different dendritic segments of dentate granule neurons and CA1 pyramidal neurons along the septo-temporal axis of hippocampus in adulthood and during aging are conspicuously absent. Here, we use a transgenic mouse line in which mature dentate granule neurons and CA1 pyramidal neurons are genetically labeled with green fluorescent protein (GFP) to investigate the effects of chronic fluoxetine treatment (18mg/kg/day) on input-specific spine remodeling and mossy fiber structural plasticity in the dorsal and ventral hippocampus in adulthood and middle age. In addition, we examine levels of adult hippocampal neurogenesis, maturation state of dentate granule neurons, neuronal activity and glutamic acid decarboxylase-67 expression in response to chronic fluoxetine in adulthood and middle age. Our studies reveal that while chronic fluoxetine fails to augment adult hippocampal neurogenesis in middle age, the middle-aged hippocampus retains high sensitivity to changes in the dentate gyrus (DG) such as dematuration, hypoactivation, and increased glutamic acid decarboxylase 67 (GAD67) expression. Interestingly, the middle-aged hippocampus shows greater sensitivity to fluoxetine-induced input-specific synaptic remodeling than the hippocampus in adulthood with the stratum-oriens of CA1 exhibiting heightened structural plasticity. The input-specific changes and circuit

Interstitial lung disease induced by fluoxetine: Systematic review of literature and analysis of Vigiaccess, Eudravigilance and a national pharmacovigilance database.

PubMed

Deidda, Arianna; Pisanu, Claudia; Micheletto, Laura; Bocchetta, Alberto; Del Zompo, Maria; Stochino, Maria Erminia

2017-06-01

We investigated a pulmonary adverse drug reaction possibly induced by fluoxetine, the Interstitial Lung Disease, by performing a systematic review of published case reports on this subject, a review of the World Health Organization VigiAccess database, of the European EudraVigilance database and of a national Pharmacovigilance database (Italian Pharmacovigilance Network). The research found a total of seven cases linking fluoxetine to Interstitial Lung Disease in the literature. 36 cases of interstitial lung disease related to fluoxetine were retrieved from the VigiAccess database (updated to July 2016), and 36 reports were found in EudraVigilance database (updated to June 2016). In the Italian Pharmacovigilance database (updated to August 2016), we found only one case of Interstitial Lung Disease, codified as "pulmonary disease". Our investigation shows that fluoxetine might be considered as a possible cause of Interstitial Lung Disease. In particular, although here we do not discuss the assessment of benefits and harms of fluoxetine, since this antidepressant is widely used, our review suggests that fluoxetine-induced Interstitial Lung Disease should be considered in patients with dyspnea, associated or not with dry cough, who are treated with this drug. An early withdrawn of fluoxetine could be useful to obtain a complete remission of this adverse drug reaction and special attention should be particularly devoted to long-term therapy, and to female and elderly patients. Although the spontaneous reporting system is affected by important limitations, drug post- marketing surveillance represents an important tool to evaluate the real world effectiveness and safety of drugs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fluoxetine protects against methamphetamine‑induced lung inflammation by suppressing oxidative stress through the SERT/p38 MAPK/Nrf2 pathway in rats.

PubMed

Wang, Yun; Gu, Yu-Han; Liu, Ming; Bai, Yang; Wang, Huai-Liang

2017-02-01

Methamphetamine (MA) abuse is a major public health and safety concern throughout the world and a growing burden on healthcare costs. The purpose of the present study was to investigate the protective effect of fluoxetine against MA‑induced chronic pulmonary inflammation and to evaluate the potential role of nuclear factor erythroid 2-related factor 2 (Nrf2)-mediated antioxidative stress. Wistar rats were divided into control, MA and two fluoxetine‑treated groups. Rats in the MA and the two fluoxetine‑treated groups were treated daily with intraperitoneal injection of 10 mg/kg MA twice daily. Rats in the two fluoxetine‑treated groups were injected intragastrically with fluoxetine (2 and 10 mg/kg) once daily, respectively. After 5 weeks, the rats were euthanized and hematoxylin and eosin staining, immunohistochemistry, western blot analysis and redox assay were performed. It was demonstrated that chronic exposure to MA can induce pulmonary inflammation in rats, with the symptoms of inflammatory cell infiltration, crowded lung parenchyma, thickened septum and a reduced number of alveolar sacs. Fluoxetine attenuated pulmonary inflammation and the expression of interleukin‑6 and tumor necrosis factor‑α in rat lungs. Fluoxetine inhibited MA‑induced increases in the expression levels of serotonin transporter (SERT) and p‑p38 mitogen‑activated protein kinase (MAPK), and reversed the MA‑induced decrease in nuclear Nrf2 and human heme oxygenase‑1 in lungs. Fluoxetine at 10 mg/kg significantly reversed the reduced glutathione (GSH) level, the ratio of GSH/oxidized glutathione, and the reactive oxygen species level in rat lungs from the MA group. These findings suggested that fluoxetine, a SERT inhibitor, has a protective effect against MA‑induced lung inflammation by suppressing oxidative stress through the SERT/p38 MAPK/Nrf2 pathway in rats.

Chronic fluoxetine treatment partly attenuates the long-term anxiety and depressive symptoms induced by MDMA ('Ecstasy') in rats.

PubMed

Thompson, Murray R; Li, Kong M; Clemens, Kelly J; Gurtman, Clint G; Hunt, Glenn E; Cornish, Jennifer L; McGregor, Iain S

2004-04-01

Use of the drug 3,4-methylenedioxymethamphetamine (MDMA, 'Ecstasy') can have long-term adverse effects on emotion in both humans and laboratory animals. The present study examined whether chronic treatment with the antidepressant drug fluoxetine could reverse such effects. Male Wistar rats were briefly exposed to MDMA (4 x 5 mg/kg over 4 h) or vehicle on 2 consecutive days. Approximately 9-12 weeks later, half of the rats received a dose of approximately 6 mg/kg/day fluoxetine in their drinking water for a 5-week period. Fluoxetine administration reduced fluid intake and body weight in MDMA and vehicle pretreated rats. After several weeks of fluoxetine treatment, rats were assessed on the social interaction test, the emergence test of anxiety and the forced swim model of depression. MDMA pretreated rats showed reduced social interaction, increased anxiety on the emergence test, and increased immobility and decreased active responses in the forced swim test. Fluoxetine treatment reversed MDMA-induced anxiety in the emergence test and depressive-like effects in the forced swim test, yet exhibited no effects on the social interaction test. MDMA pretreated rats had decreased 5-HT and 5-HIAA levels in limbic and cortical regions, and decreased density of serotonin transporter sites in the cortex. Fluoxetine treatment did not greatly affect 5-HT levels in MDMA pretreated rats, but significantly decreased 5-HIAA levels in all brain sites examined. Postmortem blood serum levels of fluoxetine and norfluoxetine did not differ in MDMA and vehicle pretreated rats. These results indicate that fluoxetine may provide a treatment option for some of the deleterious long-term effects resulting from MDMA exposure.

Inhibitory effect of chronic oral treatment with fluoxetine on capsaicin-induced external carotid vasodilatation in anaesthetised dogs.

PubMed

Muñoz-Islas, Enriqueta; González-Hernández, Abimael; Lozano-Cuenca, Jair; Ramírez-Rosas, Martha Beatríz; Medina-Santillán, Roberto; Centurión, David; MaassenVanDenBrink, Antoinette; Villalón, Carlos M

2015-10-01

During migraine, capsaicin-sensitive trigeminal sensory nerves release calcitonin gene-related peptide (CGRP), resulting in cranial vasodilatation and central nociception. Moreover, 5-HT is involved in the pathophysiology of migraine and depression. Interestingly, some limited lines of evidence suggest that fluoxetine may be effective in migraine prophylaxis, but the underlying mechanisms are uncertain. Hence, this study investigated the canine external carotid vasodilator responses to capsaicin, α-CGRP and acetylcholine before and after acute and chronic oral treatment with fluoxetine. Forty-eight vagosympathectomised male mongrel dogs were prepared to measure blood pressure, heart rate and external carotid blood flow. The thyroid artery was cannulated for infusions of agonists. In 16 of these dogs, a spinal cannula was inserted (C1-C3) for infusions of 5-HT. The external carotid vasodilator responses to capsaicin, α-CGRP and acetylcholine remained unaffected after intracarotid or i.v. fluoxetine. In contrast, the vasodilator responses to capsaicin, but not those to α-CGRP or acetylcholine, were inhibited after chronic oral treatment with fluoxetine (300 µg/kg; for 90 days) or intrathecal 5-HT. Chronic oral fluoxetine inhibited capsaicin-induced external carotid vasodilatation, and this inhibition could partly explain its potential prophylactic antimigraine action. © International Headache Society 2015.

Apoptosis-inducing factor (Aif1) mediates anacardic acid-induced apoptosis in Saccharomyces cerevisiae.

PubMed

Muzaffar, Suhail; Chattoo, Bharat B

2017-03-01

Anacardic acid is a medicinal phytochemical that inhibits proliferation of fungal as well as several types of cancer cells. It induces apoptotic cell death in various cell types, but very little is known about the mechanism involved in the process. Here, we used budding yeast Saccharomyces cerevisiae as a model to study the involvement of some key elements of apoptosis in the anacardic acid-induced cell death. Plasma membrane constriction, chromatin condensation, DNA degradation, and externalization of phosphatidylserine (PS) indicated that anacardic acid induces apoptotic cell death in S. cerevisiae. However, the exogenous addition of broad-spectrum caspase inhibitor Z-VAD-FMK or deletion of the yeast caspase Yca1 showed that the anacardic acid-induced cell death is caspase independent. Apoptosis-inducing factor (AIF1) deletion mutant was resistant to the anacardic acid-induced cell death, suggesting a key role of Aif1. Overexpression of Aif1 made cells highly susceptible to anacardic acid, further confirming that Aif1 mediates anacardic acid-induced apoptosis. Interestingly, instead of the increase in the intracellular reactive oxygen species (ROS) normally observed during apoptosis, anacardic acid caused a decrease in the intracellular ROS levels. Quantitative real-time PCR analysis showed downregulation of the BIR1 survivin mRNA expression during the anacardic acid-induced apoptosis.

Fluoxetine treatment is effective in a rat model of childhood-induced post-traumatic stress disorder.

PubMed

Ariel, Lior; Inbar, Sapir; Edut, Schachaf; Richter-Levin, Gal

2017-11-30

Although selective serotonin reuptake inhibitors (SSRIs) are first-line treatment for post-traumatic stress disorder (PTSD) patients, their therapeutic efficacy is limited. Childhood adversities are considered a risk factor for developing PTSD in adulthood but may trigger PTSD without additional trauma in some individuals. Nevertheless, just as childhood is considered a vulnerable period it may also be an effective period for preventive treatment. Using a rat model of childhood-induced PTSD, pre-pubertal stress (juvenile stress, JVS), we compared the therapeutic effects of fluoxetine and examined the effectiveness of 1 month of fluoxetine treatment following JVS and into adulthood compared to treatment in adulthood. Since not all individuals develop PTSD following a trauma, comparing only group means is not the adequate type of analysis. We employed a behavioral profiling approach, which analyzes individual differences compared to the normal behavior of a control group. Animals exposed to JVS exhibited a higher proportion of affected animals as measured using the elevated plus maze 8 weeks after JVS. Fluoxetine treatment following the JVS significantly decreased the proportion of affected animals as measured in adulthood. Fluoxetine treatment in adulthood was not effective. The results support the notion that childhood is not only a vulnerable period but also an effective period for preventive treatment.

Fluoxetine ameliorates cartilage degradation in osteoarthritis by inhibiting Wnt/β-catenin signaling.

PubMed

Miyamoto, Kentaro; Ohkawara, Bisei; Ito, Mikako; Masuda, Akio; Hirakawa, Akihiro; Sakai, Tadahiro; Hiraiwa, Hideki; Hamada, Takashi; Ishiguro, Naoki; Ohno, Kinji

2017-01-01

Abnormal activation of the Wnt/β-catenin signaling is implicated in the osteoarthritis (OA) pathology. We searched for a pre-approved drug that suppresses abnormally activated Wnt/β-catenin signaling and has a potency to reduce joint pathology in OA. We introduced the TOPFlash reporter plasmid into HCS-2/8 human chondrosarcoma cells to estimate the Wnt/β-catenin activity in the presence of 10 μM each compound in a panel of pre-approved drugs. We found that fluoxetine, an antidepressant in the class of selective serotonin reuptake inhibitors (SSRI), down-regulated Wnt/β-catenin signaling in human chondrosarcoma cells. Fluoxetine inhibited both Wnt3A- and LiCl-induced loss of proteoglycans in chondrogenically differentiated ATDC5 cells. Fluoxetine increased expression of Sox9 (the chondrogenic master regulator), and decreased expressions of Axin2 (a marker for Wnt/β-catenin signaling) and Mmp13 (matrix metalloproteinase 13). Fluoxetine suppressed a LiCl-induced increase of total β-catenin and a LiCl-induced decrease of phosphorylated β-catenin in a dose-dependent manner. An in vitro protein-binding assay showed that fluoxetine enhanced binding of β-catenin with Axin1, which is a scaffold protein forming the degradation complex for β-catenin. Fluoxetine suppressed LiCl-induced β-catenin accumulation in human OA chondrocytes. Intraarticular injection of fluoxetine in a rat OA model ameliorated OA progression and suppressed β-catenin accumulation.

Fluoxetine ameliorates cartilage degradation in osteoarthritis by inhibiting Wnt/β-catenin signaling

PubMed Central

Miyamoto, Kentaro; Ito, Mikako; Masuda, Akio; Hirakawa, Akihiro; Sakai, Tadahiro; Hiraiwa, Hideki; Hamada, Takashi; Ishiguro, Naoki; Ohno, Kinji

2017-01-01

Abnormal activation of the Wnt/β-catenin signaling is implicated in the osteoarthritis (OA) pathology. We searched for a pre-approved drug that suppresses abnormally activated Wnt/β-catenin signaling and has a potency to reduce joint pathology in OA. We introduced the TOPFlash reporter plasmid into HCS-2/8 human chondrosarcoma cells to estimate the Wnt/β-catenin activity in the presence of 10 μM each compound in a panel of pre-approved drugs. We found that fluoxetine, an antidepressant in the class of selective serotonin reuptake inhibitors (SSRI), down-regulated Wnt/β-catenin signaling in human chondrosarcoma cells. Fluoxetine inhibited both Wnt3A- and LiCl-induced loss of proteoglycans in chondrogenically differentiated ATDC5 cells. Fluoxetine increased expression of Sox9 (the chondrogenic master regulator), and decreased expressions of Axin2 (a marker for Wnt/β-catenin signaling) and Mmp13 (matrix metalloproteinase 13). Fluoxetine suppressed a LiCl-induced increase of total β-catenin and a LiCl-induced decrease of phosphorylated β-catenin in a dose-dependent manner. An in vitro protein-binding assay showed that fluoxetine enhanced binding of β-catenin with Axin1, which is a scaffold protein forming the degradation complex for β-catenin. Fluoxetine suppressed LiCl-induced β-catenin accumulation in human OA chondrocytes. Intraarticular injection of fluoxetine in a rat OA model ameliorated OA progression and suppressed β-catenin accumulation. PMID:28926590

Protective effects of melatonin on long-term administration of fluoxetine in rats.

PubMed

Khaksar, Majid; Oryan, Ahmad; Sayyari, Mansour; Rezabakhsh, Aysa; Rahbarghazi, Reza

2017-10-02

The degree and consequence of tissue injury are highly regarded during long-term exposure to selective antidepressant fluoxetine. Melatonin has been shown to palliate different lesions by scavenging free radicals, but its role in the reduction of the fluoxetine-induced injuries has been little known. Thirty-six mature male Wistar rats were randomly assigned into control and experimental groups. The experimental rats were included as following; 24mg/kg/bw fluoxetine for 4 weeks; 1mg/kg/bw melatonin for 4 weeks; fluoxetine+1-week melatonin, fluoxetine+2-week melatonin and fluoxetine+4-week melatonin. In the current experiment, we investigated weight gain, hematological and biochemical parameters, pathological injuries and oxidative status. We noted the positive effect of melatonin in weight loss of fluoxetine-treated rats (p<0.05). The significant reduction of superoxide dismutase, glutathione peroxidase, catalase activities in blood, liver, and kidneys and changes in serum total antioxidant capacity caused by fluoxetine were reversed by melatonin (p<0.05). Melatonin reduced the increased lipid peroxidation and transaminase activity in rats received fluoxetine (p<0.05). We also showed the potency of fluoxetine in inducing leukopenia, thrombocytopenia and hypochromic and macrocytic anemia which was blunted by melatonin. Both RBCs and platelets indices were also corrected. Rats received melatonin in combination with fluoxetine showed a reduction in the severity of degeneration and inflammatory changes in different tissues, brain, heart, liver, lungs, testes and kidneys as compared to the fluoxetine group. Therefore, melatonin fundamentally reversed the side effects of fluoxetine in the rat model which is comparable to human medicine. Copyright © 2017 Elsevier GmbH. All rights reserved.

Fluoxetine Facilitates Fear Extinction Through Amygdala Endocannabinoids

PubMed Central

Gunduz-Cinar, Ozge; Flynn, Shaun; Brockway, Emma; Kaugars, Katherine; Baldi, Rita; Ramikie, Teniel S; Cinar, Resat; Kunos, George; Patel, Sachin; Holmes, Andrew

2016-01-01

Pharmacologically elevating brain endocannabinoids (eCBs) share anxiolytic and fear extinction-facilitating properties with classical therapeutics, including the selective serotonin reuptake inhibitor, fluoxetine. There are also known functional interactions between the eCB and serotonin systems and preliminary evidence that antidepressants cause alterations in brain eCBs. However, the potential role of eCBs in mediating the facilitatory effects of fluoxetine on fear extinction has not been established. Here, to test for a possible mechanistic contribution of eCBs to fluoxetine's proextinction effects, we integrated biochemical, electrophysiological, pharmacological, and behavioral techniques, using the extinction-impaired 129S1/Sv1mJ mouse strain. Chronic fluoxetine treatment produced a significant and selective increase in levels of anandamide in the BLA, and an associated decrease in activity of the anandamide-catabolizing enzyme, fatty acid amide hydrolase. Slice electrophysiological recordings showed that fluoxetine-induced increases in anandamide were associated with the amplification of eCB-mediated tonic constraint of inhibitory, but not excitatory, transmission in the BLA. Behaviorally, chronic fluoxetine facilitated extinction retrieval in a manner that was prevented by systemic or BLA-specific blockade of CB1 receptors. In contrast to fluoxetine, citalopram treatment did not increase BLA eCBs or facilitate extinction. Taken together, these findings reveal a novel, obligatory role for amygdala eCBs in the proextinction effects of a major pharmacotherapy for trauma- and stressor-related disorders and anxiety disorders. PMID:26514583

Fluoxetine Facilitates Fear Extinction Through Amygdala Endocannabinoids.

PubMed

Gunduz-Cinar, Ozge; Flynn, Shaun; Brockway, Emma; Kaugars, Katherine; Baldi, Rita; Ramikie, Teniel S; Cinar, Resat; Kunos, George; Patel, Sachin; Holmes, Andrew

2016-05-01

Pharmacologically elevating brain endocannabinoids (eCBs) share anxiolytic and fear extinction-facilitating properties with classical therapeutics, including the selective serotonin reuptake inhibitor, fluoxetine. There are also known functional interactions between the eCB and serotonin systems and preliminary evidence that antidepressants cause alterations in brain eCBs. However, the potential role of eCBs in mediating the facilitatory effects of fluoxetine on fear extinction has not been established. Here, to test for a possible mechanistic contribution of eCBs to fluoxetine's proextinction effects, we integrated biochemical, electrophysiological, pharmacological, and behavioral techniques, using the extinction-impaired 129S1/Sv1mJ mouse strain. Chronic fluoxetine treatment produced a significant and selective increase in levels of anandamide in the BLA, and an associated decrease in activity of the anandamide-catabolizing enzyme, fatty acid amide hydrolase. Slice electrophysiological recordings showed that fluoxetine-induced increases in anandamide were associated with the amplification of eCB-mediated tonic constraint of inhibitory, but not excitatory, transmission in the BLA. Behaviorally, chronic fluoxetine facilitated extinction retrieval in a manner that was prevented by systemic or BLA-specific blockade of CB1 receptors. In contrast to fluoxetine, citalopram treatment did not increase BLA eCBs or facilitate extinction. Taken together, these findings reveal a novel, obligatory role for amygdala eCBs in the proextinction effects of a major pharmacotherapy for trauma- and stressor-related disorders and anxiety disorders.

Fluoxetine Exerts Age-Dependent Effects on Behavior and Amygdala Neuroplasticity in the Rat

PubMed Central

Homberg, Judith R.; Olivier, Jocelien D. A.; Blom, Tom; Arentsen, Tim; van Brunschot, Chantal; Schipper, Pieter; Korte-Bouws, Gerdien; van Luijtelaar, Gilles; Reneman, Liesbeth

2011-01-01

The selective serotonin reuptake inhibitor (SSRI) Prozac® (fluoxetine) is the only registered antidepressant to treat depression in children and adolescents. Yet, while the safety of SSRIs has been well established in adults, serotonin exerts neurotrophic actions in the developing brain and thereby may have harmful effects in adolescents. Here we treated adolescent and adult rats chronically with fluoxetine (12 mg/kg) at postnatal day (PND) 25 to 46 and from PND 67 to 88, respectively, and tested the animals 7–14 days after the last injection when (nor)fluoxetine in blood plasma had been washed out, as determined by HPLC. Plasma (nor)fluoxetine levels were also measured 5 hrs after the last fluoxetine injection, and matched clinical levels. Adolescent rats displayed increased behavioral despair in the forced swim test, which was not seen in adult fluoxetine treated rats. In addition, beneficial effects of fluoxetine on wakefulness as measured by electroencephalography in adults was not seen in adolescent rats, and age-dependent effects on the acoustic startle response and prepulse inhibition were observed. On the other hand, adolescent rats showed resilience to the anorexic effects of fluoxetine. Exploratory behavior in the open field test was not affected by fluoxetine treatment, but anxiety levels in the elevated plus maze test were increased in both adolescent and adult fluoxetine treated rats. Finally, in the amygdala, but not the dorsal raphe nucleus and medial prefrontal cortex, the number of PSA-NCAM (marker for synaptic remodeling) immunoreactive neurons was increased in adolescent rats, and decreased in adult rats, as a consequence of chronic fluoxetine treatment. No fluoxetine-induced changes in 5-HT1A receptor immunoreactivity were observed. In conclusion, we show that fluoxetine exerts both harmful and beneficial age-dependent effects on depressive behavior, body weight and wakefulness, which may relate, in part, to differential fluoxetine-induced

Effects of fluoxetine on changes of pain sensitivity in chronic stress model rats.

PubMed

Lian, Yan-Na; Chang, Jin-Long; Lu, Qi; Wang, Yi; Zhang, Ying; Zhang, Feng-Min

2017-06-09

Exposure to stress could facilitate or inhibit pain responses (stress-induced hyperalgesia or hypoalgesia, respectively). Fluoxetine is a selective serotonin (5-HT) reuptake inhibitor antidepressant. There have been contradictory reports on whether fluoxetine produces antinociceptive effects. The purpose of this study was to elucidate changes in pain sensitivity after chronic stress exposure, and the effects of fluoxetine on these changes. We measured thermal, mechanical, and formalin-induced acute and inflammatory pain by using the tail-flick, von Frey, and formalin tests respectively. The results showed that rats exposed to chronic stress exhibited thermal and formalin-induced acute and inflammatory hypoalgesia and transient mechanical hyperalgesia. Furthermore, fluoxetine promoted hypoalgesia in thermal and inflammatory pain and induced mechanical hyperalgesia. Our results indicate that the 5-HT system could be involved in hypoalgesia of thermal and inflammatory pain and induce transient mechanical hyperalgesia after stress exposure. Copyright © 2017 Elsevier B.V. All rights reserved.

Chronic treatment with fluoxetine modulates vascular adrenergic responses by inhibition of pre- and post-synaptic mechanisms.

PubMed

Pereira, Camila A; Rodrigues, Fernanda L; Ruginsk, Silvia G; Zanotto, Camila Z; Rodrigues, José A; Duarte, Diego A; Costa-Neto, Claudio M; Resstel, Leonardo B; Carneiro, Fernando S; Tostes, Rita C

2017-04-05

Fluoxetine, a serotonin reuptake inhibitor (SSRI), has other effects in addition to blocking serotonin reuptake, including changes in the vasomotor tone. Whereas many studies focused on the acute effects of fluoxetine in the vasculature, its chronic effects are still limited. In the present study, we tested the hypothesis that chronic fluoxetine treatment modulates adrenergic vascular responses by interfering with post- and pre-synaptic mechanisms. Wistar rats were treated with vehicle (water) or chronic fluoxetine (10mg/kg/day) for 21 days. Blood pressure (BP) and heart rate were measured. Vascular reactivity was evaluated in perfused mesenteric arterial beds (MAB) and in mesenteric resistance arteries. Protein expression by western blot analysis or immunohistochemistry, β-arrestin recruitment by BRET and calcium influx by FLIPR assay. Fluoxetine treatment decreased phenylephrine (PE)-induced, but not electrical-field stimulation (EFS)-induced vasoconstriction. Fluoxetine-treated rats exhibited increased KCl-induced vasoconstriction, which was abolished by prazosin. Desipramine, an inhibitor of norepinephrine (NA) reuptake, increased EFS-induced vasoconstrictor response in vehicle-treated, but not in fluoxetine-treated rats. Chronic treatment did not alter vascular expression of α 1 adrenoceptor, phosphorylation of PKCα or ERK 1/2 and RhoA. On the other hand, vascular contractions to calcium (Ca 2+ ) as well as Ca 2+ influx in mesenteric arteries were increased, while intracellular Ca 2+ storage was decreased by the chronic treatment with fluoxetine. In vitro, fluoxetine decreased vascular contractions to PE, EFS and Ca 2+ , but did not change β-arrestin activity. In conclusion, chronic treatment with fluoxetine decreases sympathetic-mediated vascular responses by mechanisms that involve inhibition of NA release/reuptake and decreased Ca 2+ stores. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of nitric oxide synthesis inhibitor or fluoxetine treatment on depression-like state and cardiovascular changes induced by chronic variable stress in rats.

PubMed

Almeida, Jeferson; Duarte, Josiane O; Oliveira, Leandro A; Crestani, Carlos C

2015-01-01

Comorbidity between mood disorders and cardiovascular disease has been described extensively. However, available antidepressants can have cardiovascular side effects. Treatment with selective inhibitors of neuronal nitric oxide synthase (nNOS) induces antidepressant effects, but whether the antidepressant-like effects of these drugs are followed by cardiovascular changes has not been previously investigated. Here, we tested in male rats exposed to chronic variable stress (CVS) the hypothesis that nNOS blockers are advantageous compared with conventional antidepressants in terms of cardiovascular side effects. We compared the effects of chronic treatment with the preferential nNOS inhibitor 7-nitroindazole (7-NI) with those evoked by the conventional antidepressant fluoxetine on alterations that are considered as markers of depression (immobility in the forced swimming test, FST, decreased body weight gain and increased plasma corticosterone concentration) and cardiovascular changes caused by CVS. Rats were exposed to a 14-day CVS protocol, while being concurrently treated daily with either 7-NI (30 mg/kg) or fluoxetine (10 mg/kg). Fluoxetine and 7-NI prevented the increase in immobility in the FST induced by CVS and reduced plasma corticosterone concentration in stressed rats. Both these treatments also prevented the CVS-evoked reduction of the depressor response to vasodilator agents and baroreflex changes. Fluoxetine and 7-NI-induced cardiovascular changes independent of stress exposure, including cardiac autonomic imbalance, increased intrinsic heart rate and vascular sympathetic modulation, a reduction of the pressor response to vasoconstrictor agents, and impairment of baroreflex activity. Altogether, these findings provide evidence that fluoxetine and 7-NI have similar effects on the depression-like state induced by CVS and on cardiovascular function.

Fluoxetine regulates mTOR signalling in a region-dependent manner in depression-like mice

PubMed Central

Liu, Xiao-Long; Luo, Liu; Mu, Rong-Hao; Liu, Bin-Bin; Geng, Di; Liu, Qing; Yi, Li-Tao

2015-01-01

Previous studies have demonstrated that the mammalian target of rapamycin (mTOR) signaling pathway has an important role in ketamine-induced, rapid antidepressant effects despite the acute administration of fluoxetine not affecting mTOR phosphorylation in the brain. However, the effects of long-term fluoxetine treatment on mTOR modulation have not been assessed to date. In the present study, we examined whether fluoxetine, a type of commonly used antidepressant agent, alters mTOR signaling following chronic administration in different brain regions, including the frontal cortex, hippocampus, amygdala and hypothalamus. We also investigated whether fluoxetine enhanced synaptic protein levels in these regions via the activation of the mTOR signaling pathway and its downstream regulators, p70S6K and 4E-BP-1. The results indicated that chronic fluoxetine treatment attenuated the chronic, unpredictable, mild stress (CUMS)-induced mTOR phosphorylation reduction in the hippocampus and amygdala of mice but not in the frontal cortex or the hypothalamus. Moreover, the CUMS-decreased PSD-95 and synapsin I levels were reversed by fluoxetine, and these effects were blocked by rapamycin only in the hippocampus. In conclusion, our findings suggest that chronic treatment with fluoxetine can induce synaptic protein expression by activating the mTOR signaling pathway in a region-dependent manner and mainly in the hippocampus. PMID:26522512

Fluoxetine regulates mTOR signalling in a region-dependent manner in depression-like mice.

PubMed

Liu, Xiao-Long; Luo, Liu; Mu, Rong-Hao; Liu, Bin-Bin; Geng, Di; Liu, Qing; Yi, Li-Tao

2015-11-02

Previous studies have demonstrated that the mammalian target of rapamycin (mTOR) signaling pathway has an important role in ketamine-induced, rapid antidepressant effects despite the acute administration of fluoxetine not affecting mTOR phosphorylation in the brain. However, the effects of long-term fluoxetine treatment on mTOR modulation have not been assessed to date. In the present study, we examined whether fluoxetine, a type of commonly used antidepressant agent, alters mTOR signaling following chronic administration in different brain regions, including the frontal cortex, hippocampus, amygdala and hypothalamus. We also investigated whether fluoxetine enhanced synaptic protein levels in these regions via the activation of the mTOR signaling pathway and its downstream regulators, p70S6K and 4E-BP-1. The results indicated that chronic fluoxetine treatment attenuated the chronic, unpredictable, mild stress (CUMS)-induced mTOR phosphorylation reduction in the hippocampus and amygdala of mice but not in the frontal cortex or the hypothalamus. Moreover, the CUMS-decreased PSD-95 and synapsin I levels were reversed by fluoxetine, and these effects were blocked by rapamycin only in the hippocampus. In conclusion, our findings suggest that chronic treatment with fluoxetine can induce synaptic protein expression by activating the mTOR signaling pathway in a region-dependent manner and mainly in the hippocampus.

Up-regulation of melanin synthesis by the antidepressant fluoxetine.

PubMed

Liao, Sha; Shang, Jing; Tian, Xiaoli; Fan, Xueqi; Shi, Xiupu; Pei, Siran; Wang, Qian; Yu, Boyang

2012-08-01

Fluoxetine, a member of the class of selective serotonin reuptake inhibitors, is a potent antidepressant commonly used in clinical practice. Here, we report that fluoxetine increases cellular tyrosinase (TYR) activity, enhances the protein levels of microphthalmia-associated transcription factor (MITF), TYR and tyrosinase-related protein-1 (TRP-1) and eventually leads to a dramatic increase in melanin production in both murine B16F10 melanoma cells and normal human melanocytes (NHMCs). In well-characterized C57BL/6 mouse models, systemic application of fluoxetine increased hair pigmentation by up-regulating hair follicular MITF, TYR, TRP-1 and tyrosinase-related protein-2 (TRP-2) protein levels. Using a serotonin 1A receptor (SR1A) antagonist and RNA interference (RNAi) technique, we revealed that SR1A appears to be one of the involved pathways in the fluoxetine-induced melanogenesis in B16F10 cells. These results suggest that fluoxetine may hold a significant therapeutic potential for treating skin hypopigmentation disorders, and SR1A may serve as a novel target in modulating melanogenesis. © 2012 John Wiley & Sons A/S.

Chronic treatment with fluoxetine and sertraline prevents forced swimming test-induced hypercontractility of rat detrusor muscle.

PubMed

Bilge, Sirri; Bozkurt, Ayhan; Bas, Duygu B; Aksoz, Elif; Savli, Evren; Ilkaya, Fatih; Kesim, Yuksel

2008-01-01

Serotonin (5-hydroxytryptamine, 5-HT) reuptake inhibitors represent important targets for the development of new treatments for detrusor overactivity and urinary incontinence. The present study was undertaken to investigate the effects of the forced swimming test (FST) on the contractile response of isolated rat detrusor muscle and to examine the effects of in vivo treatments of fluoxetine and sertraline on altered detrusor muscle contractility. Fluoxetine (20 mg/kg ip) and sertraline (10 mg/kg ip) were administered once a day for 14 days. Rats were exposed to the FST on the 15th day. After the test, detrusor muscles were removed and placed in organ baths, and the contraction responses induced by carbachol, potassium chloride (KCl) and electrical field stimulation (EFS) were recorded. The contractile responses of detrusor muscle strips to carbachol and electrical field stimulation were found to be increased at all carbachol doses and frequencies, respectively. FST also increased the contractile responses to KCl, which is used to test the differences in postreceptor-mediated contractions. The hypercontractile responses of detrusor strips to carbachol, EFS and KCl were abolished by treatment with both fluoxetine and sertraline. These treatments also decreased the immobility duration in the FST consistent with an antidepressant-like effect in this test. The results of this study provide the first evidence that FST increases contractility of the rat detrusor muscle, and this hypercontractility was abolished by chronic treatments of fluoxetine and sertraline at antidepressant doses by decreasing the postreceptor-mediated events.

Reactive oxygen species in the tumor niche triggers altered activation of macrophages and immunosuppression: Role of fluoxetine.

PubMed

Ghosh, Sayan; Mukherjee, Sudeshna; Choudhury, Sreetama; Gupta, Payal; Adhikary, Arghya; Baral, Rathindranath; Chattopadhyay, Sreya

2015-07-01

Macrophages are projected as one of the key players responsible for the progression of cancer. Classically activated (M1) macrophages are pro-inflammatory and have a central role in host defense, while alternatively activated (M2) macrophages are associated with immunosuppression. Macrophages residing at the site of neoplastic growth are alternately activated and are referred to as tumor-associated macrophages (TAMs). These "cooperate" with tumor tissue, promoting increased proliferation and immune escape. Selective serotonin reuptake inhibitors like fluoxetine have recently been reported to possess anti-inflammatory activity. We used fluoxetine to target tumor-associated inflammation and consequent alternate polarization of macrophages. We established that murine peritoneal macrophages progressed towards an altered activation state when exposed to cell-free tumor fluid, as evidenced by increased IL-6, IL-4 and IL-10 levels. These polarized macrophages showed significant pro-oxidant bias and increased p65 nuclear localization. It was further observed that these altered macrophages could induce oxidative insult and apoptosis in cultured mouse CD3(+) T cells. To validate these findings, we replicated key experiments in vivo, and observed that there was increased serum IL-6, IL-4 and IL-10 in tumor-bearing animals, with increased % CD206(+) cells within the tumor niche. TAMs showed increased nuclear localization of p65 with decreased Nrf2 expression in the nucleus. These results were associated with increase in apoptosis of CD3(+) T cells co-cultured with TAM-spent media. We could establish that fluoxetine treatment could specifically re-educate the macrophages both in vitro and in vivo by skewing their phenotype such that immune suppression mediated by tumor-dictated macrophages was successfully mitigated. Copyright © 2015 Elsevier Inc. All rights reserved.

Effect of electrostatic interaction between fluoxetine and lipid membranes on the partitioning of fluoxetine investigated using second derivative spectrophotometry and FTIR.

PubMed

Do, Tien T T; Dao, Uyen P N; Bui, Huong T; Nguyen, Trang T

2017-10-01

The interaction between a drug molecule and lipid bilayers is highly important regarding the pharmaceutical activity of the drug. In this study, the interaction of fluoxetine, a well-known selective serotonin reuptake inhibitor antidepressant and lipid bilayers composed of 1,2-dipalmitoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (DPPG) and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) was studied from the aspect of electrostatics using second derivative spectrophotometry and Fourier transform infrared spectroscopy (FTIR) in order to provide insights into the drug behavior. Changing pH from 7.4 to 9.5 to increases the neutral state of fluoxetine, the partitioning of fluoxetine into the zwitterionic DPPC large unilamellar vesicles (LUVs) was increased whereas it was reduced into the negatively charged DPPG LUVs. Fluoxetine was found to exhibit a disordering effect on the acyl chains of DPPC and DPPG bilayers upon its partitioning. In addition, increasing concentration of NaCl lessened the binding of fluoxetine into DPPG bilayers due to the reduction in electrostatic attraction between positively charged fluoxetine and negatively charged DPPG LUVs. In addition, the FTIR study revealed that increasing the NaCl concentration could trigger the shift to higher frequency of the CH 2 stretching as well as the notable blue shift in the PO 2 - regions of DPPG, indicating that fluoxetine had deeper penetration into DPPG LUVs. The differences in the NaCl concentration showed a negligible effect on the incorporation of fluoxetine into the zwitterionic DPPC LUVs. In summary, the electrostatic interaction plays an important role on the partitioning of a cationic amphiphilic SSIR drug into the lipid bilayers and the drug partitioning induces the lipids' conformational change. These imply a possible influence on the drug pharmacology. Copyright © 2017 Elsevier B.V. All rights reserved.

Modulation of Radiation-Induced Apoptosis by Thiolamines

NASA Technical Reports Server (NTRS)

Warters, R. L.; Roberts, J. C.; Wilmore, B. H.; Kelley, L. L.

1997-01-01

Exposure to the thiolamine radioprotector N-(2-mercaptoethyl)-1,3-propanediamine (WR-1065) induced apoptosis in the mouse TB8-3 hybridoma after 60-minute (LD(sub50) = 4.5mM) or during a 20-hour (LD(sub50) = 0.15 mM) exposure. In contrast, a 20-hour exposure to 17 mM L-cysteine or 10 mM cysteamine was required to induce 50 percent apoptosis within 20 hours. Apoptosis was not induced by either a 60-minute or 20-hour exposure to 10 mM of the thiazolidime prodrugs ribose-cysteine (RibCys) or ribose-cysteamine (RibCyst). Thiolamine-induced apoptosis appeared to be a p53-independent process since it was induced by WR-1065 exposure in human HL60 cells. Exposure to WR-1065 (4mM for 15 minutes) or cysteine (10mM for 60 minutes) before and during irradiation protected cells against the induction of both DNA double-strand breaks and apoptosis, while exposure to RibCys (10 mM for 3 hours) did not. Treatment with either WR-1065, cysteine, RibCys or RibCyst for 60 minutes beginning 60 minutes after irradiation did not affect the level of radiation-induced apoptosis. In contrast, treatment with either cysteine, cysteamine or RibCys for 20 hours beginning 60 minutes after irradiation enhanced radiation-induced apoptosis. Similar experiments could not be conducted with WR-1065 because of its extreme toxicity. Our results indicate that thiolamine enhancement of radiation-induced apoptosis is not involved in their previously reported capacity to reduce radiation-induced mutations.

Aspartame-induced apoptosis in PC12 cells.

PubMed

Horio, Yukari; Sun, Yongkun; Liu, Chuang; Saito, Takeshi; Kurasaki, Masaaki

2014-01-01

Aspartame is an artificial sweetner added to many low-calorie foods. The safety of aspartame remains controversial even though there are many studies on its risks. In this study, to understand the physiological effects of trace amounts of artificial sweetners on cells, the effects of aspartame on apoptosis were investigated using a PC12 cell system. In addition, the mechanism of apoptosis induced by aspartame in PC12 cells and effects on apoptotic factors such as cytochrome c, apoptosis-inducing factor, and caspase family proteins were studied by Western blotting and RT-PCR. Aspartame-induced apoptosis in PC12 cells in a dose-dependent manner. In addition, aspartame exposure increased the expressions of caspases 8 and 9, and cytochrome c. These results indicate that aspartame induces apoptosis mainly via mitochondrial pathway involved in apoptosis due to oxigen toxicity. Copyright © 2013 Elsevier B.V. All rights reserved.

Effects of in vitro, acute and chronic treatment with fluoxetine on the sympathetic neurotransmission of rat vas deferens.

PubMed

Pedroso, Shaista Poppe; de Souza, Bruno Palmieri; Jurkiewicz, Aron; Juriewicz, Neide H; da Silva Junior, Edilson Dantas

2017-03-01

It is described that fluoxetine treatment is able to induce ejaculatory disorders. However, the exact mechanism is still not fully understood. Therefore, this study was carried out to further evaluate the anti-ejaculatory effects of fluoxetine, using different approaches (in vitro or in vivo treatments), on the sympathetic neurotransmission of the rat vas deferens. Vas deferens from male Wistar rats were used to check the in vitro effects of fluoxetine 10 -6 M, 3.10 -6 M or 10 -5 M. Animals were also acutely (20mg/kg, i.p. 4h or 24h) or chronically (10mg/kg, i.p., 30days) treated with fluoxetine or drug-free vehicle. The vas deferens from non-treated and treated animals were isolated and mounted in an isolated organ bath for the study of the contractions induced by adrenergic agonists, tyramine, 5-HT, Ca 2+ or electrical field stimulation. In vitro or acute treatment with fluoxetine decreased the contraction induced by agonists, Ca 2+ or electrical field stimulation. The chronic treatment with fluoxetine decreased the contractions induced agonists, tyramine or Ca 2+ , but did not modify the contractions induced by electrical field stimulation. We have shown that in vitro or in vivo fluoxetine treatment is able to alter the sympathetic neurotransmission of the rat vas deferens which could be related to alterations in the calcium signalling. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparison of fluoxetine and 1-methyl-L-tryptophan in treatment of depression-like illness in Bacillus Calmette-Guerin-induced inflammatory model of depression in mice.

PubMed

Rana, Proteesh; Sharma, Amit K; Jain, Smita; Deshmukh, Pravin; Bhattacharya, S K; Banerjee, B D; Mediratta, Pramod K

2016-11-01

The inflammatory response system has been implicated in the pathophysiology of major depression. The pro-inflammatory cytokines like interferon-γ induce the enzyme indoleamine-2,3-dioxygenase (IDO) of the kynurenine pathway of tryptophan metabolism. The induction of IDO reduces the availability of tryptophan for serotonin synthesis. Furthermore, the metabolites of kynurenine pathway have neurotoxic property, which along with decreased serotonin may account for depression-like illness. The aim of this study was to compare the effects of treatment with fluoxetine and 1-methyl-L-tryptophan (1-MT) on Bacillus Calmette-Guerin (BCG)-induced inflammatory model of depression in mice. Behavioral tests included locomotor activity, forced swim test (FST) and tail suspension test (TST). Oxidative stress was assessed by examining the levels of thiobarbituric acid reactive species (TBARS) and non-protein thiols (NP-SH) in homogenized whole brain samples. Comet assays were performed to assess neurotoxicity. The results of this study demonstrate that BCG treatment resulted in an increase in duration of immobility in FST and TST as compared to the saline group. Further, it produced a significant increase in the brain TBARS levels and decrease in the brain NP-SH levels. The hippocampal tissue from BCG group had significantly more comet cells than the saline group. 1-MT and fluoxetine were able to reverse the BCG-induced depression-like behavior and the derangement in oxidative stress parameters. Fluoxetine and 1-MT also reversed the BCG-induced neurotoxicity in such mice. 1-Methyl-L-tryptophan exhibits antidepressant-like effect comparable to that of fluoxetine in treating BCG-induced depression-like behavior in mice.

Chronic fluoxetine treatment induces anxiolytic responses and altered social behaviors in medaka, Oryzias latipes.

PubMed

Ansai, Satoshi; Hosokawa, Hiroshi; Maegawa, Shingo; Kinoshita, Masato

2016-04-15

Medaka (Oryzias latipes) is a small freshwater teleost that is an emerging model system for neurobehavioral research and toxicological testing. The selective serotonin reuptake inhibitor class of antidepressants such as fluoxetine is one of the widely prescribed drugs, but little is known about the effects of these drugs on medaka behaviors. To assess the behavioral effects of fluoxetine, we chronically administrated fluoxetine to medaka adult fish and analyzed the anxiety-related and social behaviors using five behavioral paradigms (diving, open-field, light-dark transition, mirror-biting, and social interaction) with an automated behavioral testing system. Fish chronically treated with fluoxetine exhibited anxiolytic responses such as an overall increased time spent in the top area in the diving test and an increased time spent in center area in the open-field test. Analysis of socially evoked behavior showed that chronic fluoxetine administration decreased the number of mirror biting times in the mirror-biting test and increased latency to first contact in the social interaction test. Additionally, chronic fluoxetine administration reduced the horizontal locomotor activity in the open-field test but not the vertical activity in the diving test. These investigations are mostly consistent with previous reports in the other teleost species and rodent models. These results indicate that behavioral assessment in medaka adult fish will become useful for screening of effects of pharmaceutical and toxicological compounds in animal behaviors. Copyright © 2016 Elsevier B.V. All rights reserved.

Modulation of the subthalamic nucleus activity by serotonergic agents and fluoxetine administration.

PubMed

Aristieta, A; Morera-Herreras, T; Ruiz-Ortega, J A; Miguelez, C; Vidaurrazaga, I; Arrue, A; Zumarraga, M; Ugedo, L

2014-05-01

Within the basal ganglia, the subthalamic nucleus (STN) is the only glutamatergic structure and occupies a central position in the indirect pathway. In rat, the STN receives serotonergic input from the dorsal raphe nucleus and expresses serotonergic receptors. This study examined the consequences of serotonergic neurotransmission modulation on STN neuron activity. In vivo single-unit extracellular recordings, HPLC determination, and rotarod and bar test were performed in control, 4-chloro-DL-phenylalanine methyl ester hydrochloride- (pCPA, a serotonin synthesis inhibitor) and chronically fluoxetine-treated rats. The pCPA treatment and the administration of serotonin (5-HT) receptor antagonists increased number of bursting neurons in the STN. The systemic administration of the 5-HT(1A) agonist, 8-OH-DPAT, decreased the firing rate and increased the coefficient of variation of STN neurons in pCPA-treated rats but not in control animals. Additionally, microinjection of 8-OH-DPAT into the STN reduced the firing rate of STN neurons, while microinjection of the 5-HT(2C) agonist, Ro 60-0175, increased the firing rate in both control and fluoxetine-treated animals. Finally, the fluoxetine challenge increased the firing rate of STN neurons in fluoxetine-treated rats and induced catalepsy. Our results indicate that the depletion and the blockage of 5-HT modify STN neuron firing pattern. STN neuron activity is under the control of 5-HT(1A) and 5-HT(2C) receptors located both inside and outside the STN. Finally, fluoxetine increases STN neuron activity in chronically fluoxetine-treated rats, which may explain the role of this nucleus in fluoxetine-induced extrapyramidal side effects.

Effects of combined nicotine and fluoxetine treatment on adult hippocampal neurogenesis and conditioned place preference.

PubMed

Faillace, M P; Zwiller, J; Bernabeu, R O

2015-08-06

Adult neurogenesis occurs in mammals within the dentate gyrus, a hippocampal subarea. It is known to be induced by antidepressant treatment and reduced in response to nicotine administration. We checked here whether the antidepressant fluoxetine would inverse the decrease in hippocampal neurogenesis caused by nicotine. It is shown that repeated, but not a single injection of rats with fluoxetine was able to abolish the decrease in adult dentate cell proliferation produced by nicotine treatment. We measured the expression of several biochemical parameters known to be associated with neurogenesis in the dentate gyrus. Both drugs increased the expression of p75 neurotrophin receptor, which promotes proliferation and early maturation of dentate gyrus cells. Using the conditioned place preference (CPP) paradigm, we also gave both drugs in a context in which their rewarding properties could be measured. Fluoxetine produced a significant but less robust CPP than nicotine. A single injection of fluoxetine was found to reduce nicotine-induced CPP. Moreover, the rewarding properties of nicotine were completely abolished in response to repeated fluoxetine injections. Expression of nicotine-induced CPP was accompanied by an increase of phospho-CREB (cyclic AMP-responsive element-binding protein) and HDAC2 (histone deacetylase 2) expression in the nucleus accumbens. The data suggest that fluoxetine reward, as opposed to nicotine reward, depends on dentate gyrus neurogenesis. Since fluoxetine was able to disrupt the association between nicotine and the environment, this antidepressant may be tested as a treatment for nicotine addiction using cue exposure therapy. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Fluoxetine signature on hippocampal MAPK signalling in sex-dependent manner.

PubMed

Mitic, Milos; Lukic, Iva; Bozovic, Natalija; Djordjevic, Jelena; Adzic, Miroslav

2015-02-01

A growing body of evidence indicates that mitogen-activated protein kinase (MAPK) participates in various stress-induced responses and is considered to be one of the pathophysiological mechanisms in depression. Surprisingly, the effect of antidepressants on MAPKs is almost unexplored, particularly from the perspective of sexes. The present study investigates the cytoplasm-nuclear distribution of MAPK family, c-Jun N-terminal kinases (JNKs) 1, 2 and 3; extracellular signal-regulated kinases (ERKs) 1 and 2; and p38 kinases, as well as their phosphoisoforms in the hippocampus of chronically stressed female and male rats and upon chronic fluoxetine treatment. Additionally, we analysed crosstalk between MAPK signalling and depressive-like behaviour which correlated with brain-derived neurotrophic factor (BDNF) expression. Our results emphasize a gender-specific and compartment-dependent response of MAPKs to stress and fluoxetine. In females, stress decreased pp38 and pJNK and induced cytosolic retention of pERKs which reduced all nuclear pMAPKs. These changes correlated with altered BDNF expression and behaviour. Similarly, in males, stress decreased pp38 but promoted nuclear translocation of pJNKs and pERKs. These stress alterations of pMAPKs in males were not associated with BDNF expression and depressive-like behaviour. Fluoxetine treatment in stressed females upregulated whole pMAPK signalling particularly those in nucleus which was followed with BDNF expression and normalization of behaviour. In stressed males, fluoxetine affected only cytosolic pJNKs, while nuclear pMAPK signalling and BDNF expression were unaffected even though fluoxetine normalized behaviour. Overall, our results suggest existence of gender-specific mechanism of fluoxetine on nuclear pMAPK/BDNF signalling and depressive-like behaviour and reinforce the antidepressant dogma that females and males respond differently to certain antidepressants.

Mitochondrial dysfunction in lyssavirus-induced apoptosis.

PubMed

Gholami, Alireza; Kassis, Raïd; Real, Eléonore; Delmas, Olivier; Guadagnini, Stéphanie; Larrous, Florence; Obach, Dorothée; Prevost, Marie-Christine; Jacob, Yves; Bourhy, Hervé

2008-05-01

Lyssaviruses are highly neurotropic viruses associated with neuronal apoptosis. Previous observations have indicated that the matrix proteins (M) of some lyssaviruses induce strong neuronal apoptosis. However, the molecular mechanism(s) involved in this phenomenon is still unknown. We show that for Mokola virus (MOK), a lyssavirus of low pathogenicity, the M (M-MOK) targets mitochondria, disrupts the mitochondrial morphology, and induces apoptosis. Our analysis of truncated M-MOK mutants suggests that the information required for efficient mitochondrial targeting and dysfunction, as well as caspase-9 activation and apoptosis, is held between residues 46 and 110 of M-MOK. We used a yeast two-hybrid approach, a coimmunoprecipitation assay, and confocal microscopy to demonstrate that M-MOK physically associates with the subunit I of the cytochrome c (cyt-c) oxidase (CcO) of the mitochondrial respiratory chain; this is in contrast to the M of the highly pathogenic Thailand lyssavirus (M-THA). M-MOK expression induces a significant decrease in CcO activity, which is not the case with M-THA. M-MOK mutations (K77R and N81E) resulting in a similar sequence to M-THA at positions 77 and 81 annul cyt-c release and apoptosis and restore CcO activity. As expected, the reverse mutations, R77K and E81N, introduced in M-THA induce a phenotype similar to that due to M-MOK. These features indicate a novel mechanism for energy depletion during lyssavirus-induced apoptosis.

Artesunate induces AIF-dependent apoptosis in A549 cells

NASA Astrophysics Data System (ADS)

Zhou, Chen-juan; Chen, Tong-Sheng

2012-03-01

Artesunate (ART), a semi-synthetic derivative of the sesquiterpene artemisinin extracted from the Chinese herb Artemisia annua, exerts a broad spectrum of clinical activity against human cancers. It has been shown that ART induces cancer cells death through apoptosis pathway. This study investigated whether ART treatment induced reactive oxygen species (ROS)-dependent cell death in the apoptosis fashion in human lung adenocarconoma A549 cell line and the proapoptotic protein apoptosis inducing factor (AIF) is involved in ART-induced apoptosis. Cells treated with ART exhibited typical apoptotic morphology as chromatin condensation, margination and shrunken nucleus. ART treatment also induced a loss of mitochondrial membrane potential and AIF release from mitochondria. Silencing AIF can remarkable attenuated ART-induced apoptosis. Collectively, ART induces apoptosis by caspase-independent intrinsic pathway in A549 cells.

Serotoninergic manipulation, meal-induced satiety and eating pattern: effect of fluoxetine in obese female subjects.

PubMed

Lawton, C L; Wales, J K; Hill, A J; Blundell, J E

1995-07-01

Twelve nondepressed healthy female obese subjects (BMI > 30 kg/m2) took part in a study which conformed to a double-blind randomized crossover design. Each subject acted as her own control across 2 weeks of treatment with either 60 mg of the 5-HT reuptake inhibitor fluoxetine or matching placebo. On days 7 and 14 of both treatment phases subjects were provided with fixed energy lunch meals high in either CHO or fat. The effect of these meals on satiety during the fluoxetine and placebo phases was assessed by a battery of procedures. Subjects felt less hungry after consuming the high CHO meal than after consuming the high-fat meal. They also felt less hungry when taking fluoxetine than when taking the placebo. Analysis of energy intake from the test meal revealed a main effect of prior lunch meal type (high CHO or high fat) and a main effect of drug treatment. Subjects consumed an average of 574 kcal following the high CHO meal compared to 689 kcal following the high-fat meal. Subjects also consumed an average of 532 kcal when taking fluoxetine compared to 730 kcal when taking the placebo. Fluoxetine did not exert any significant effects on macronutrient selection. Mean daily energy intake, calculated from food diary records, was 1881 kcal when subjects were taking the placebo compared to 1460 kcal when taking fluoxetine (a reduction of 22.4%). Fluoxetine treatment produced a significant weight loss of 1.97 kg over the two weeks of treatment compared to a weight loss of only 0.04 kg on placebo.

Stress-induced activation of the brainstem Bcl-xL gene expression in rats treated with fluoxetine: correlations with serotonin metabolism and depressive-like behavior.

PubMed

Shishkina, Galina T; Kalinina, Tatyana S; Berezova, Inna V; Dygalo, Nikolay N

2012-01-01

Mechanisms underlying stress-induced depression and antidepressant drug action were shown to involve alterations in serotonergic (5-HT) neurotransmission and expression of genes coding for proteins associated with neurotrophic signaling pathways and cell-survival in the hippocampus and cortex. Expression of these genes in the brainstem containing 5-HT neurons may also be related to vulnerability or resilience to stress-related psychopathology. Here we investigated 5-HT markers and expression of genes for Brain-Derived Neurotrophic Factor (BDNF) and apoptotic proteins in the brainstem in relation to swim stress-induced behavioral despair. We found that anti-apoptotic Bcl-xL gene is sensitive to stress during the course of fluoxetine administration. Responsiveness of this gene to stress appeared concomitantly with an antidepressant-like effect of fluoxetine in the forced swim test. Bcl-xL transcript levels showed negative correlations with duration of immobility in the test and 5-HT turnover in the brainstem. In contrast, BDNF and pro-apoptotic protein Bax mRNA levels were unchanged by either fluoxetine or stress, suggesting specificity of Bcl-xL gene responses to these treatments. We also found that the levels of mRNAs for tryptophan hydroxylase-2 (TPH2) and 5-HT transporter (5-HTT) were significantly down-regulated following prolonged treatment with fluoxetine, but were not affected by stress. Unlike TPH2 and 5-HTT, 5-HT1A receptor mRNA levels were not altered by fluoxetine but significantly increased in response to swim stress. These data show that long-term fluoxetine treatment leads to changes in 5-HT and Bcl-xL responses to stress associated with antidepressant-like effects of the drug. This article is part of a Special Issue entitled 'Anxiety and Depression'. Copyright © 2011 Elsevier Ltd. All rights reserved.

Subacute administration of fluoxetine prevents short-term brain hypometabolism and reduces brain damage markers induced by the lithium-pilocarpine model of epilepsy in rats.

PubMed

Shiha, Ahmed Anis; de Cristóbal, Javier; Delgado, Mercedes; Fernández de la Rosa, Rubén; Bascuñana, Pablo; Pozo, Miguel A; García-García, Luis

2015-02-01

The role of serotonin (5-hydroxytryptamine; 5-HT) in epileptogenesis still remains controversial. In this regard, it has been reported that serotonergic drugs can alter epileptogenesis in opposite ways. The main objective of this work was to investigate the effect of the selective 5-HT selective reuptake inhibitor (SSRI) fluoxetine administered subacutely (10mg/kg/day×7 days) on the eventual metabolic impairment induced by the lithium-pilocarpine model of epilepsy in rats. In vivo 2-deoxy-2-[(18)F]fluoro-d-glucose ([(18)F] FDG) positron emission tomography (PET) was performed to assess the brain glucose metabolic activity on days 3 and 30 after the insult. In addition, at the end of the experiment (day 33), several histochemical and neurochemical assessments were performed for checking the neuronal functioning and integrity. Three days after the insult, a marked reduction of [(18)F] FDG uptake (about 30% according to the brain region) was found in all brain areas studied. When evaluated on day 30, although a hypometabolism tendency was observed, no statistically significant reduction was present in any region analyzed. In addition, lithium-pilocarpine administration was associated with medium-term hippocampal and cortical damage, since it induced neurodegeneration, glial activation and augmented caspase-9 expression. Regarding the effect of fluoxetine, subacute treatment with this SSRI did not significantly reduce the mortality rate observed after pilocarpine-induced seizures. However, fluoxetine did prevent not only the short-term metabolic impairment, but also the aforementioned signs of neuronal damage in surviving animals to lithium-pilocarpine protocol. Finally, fluoxetine increased the density of GABAA receptor both at the level of the dentate gyrus and CA1-CA2 regions in pilocarpine-treated animals. Overall, our data suggest a protective role for fluoxetine against pilocarpine-induced brain damage. Moreover, this action may be associated with an increase of

Fluoxetine: clinical pharmacology and physiologic disposition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lemberger, L.; Bergstrom, R.F.; Wolen, R.L.

Fluoxetine (30 mg), administered for 7 days to normal volunteers, produced a 66% inhibition of tritiated serotonin uptake into platelets. Plasma concentrations of fluoxetine correlated positively with inhibition of serotonin uptake. Fluoxetine is well absorbed after oral administration in both the fed and fasted states and demonstrates dose proportionality. Fluoxetine disappears from plasma with a half-life of 1-3 days; its metabolite norfluoxetine has a plasma half-life of 7-15 days. After administration of /sup 14/C-fluoxetine, approximately 65% of the administered dose of radioactivity is recovered in urine and about 15% in feces. Fluoxetine, given as a single dose or in multiplemore » doses over 8 days, did not produce significant effects on the plasma disappearance of warfarin, diazepam, tolbutamide, or chlorothiazide. Coadministration of fluoxetine and ethanol did not result in an increase from control values in the blood ethanol levels, nor did it produce significant changes in physiologic, psychometric, or psychomotor activity. Pharmacokinetics of fluoxetine in the elderly and normal volunteers appear to be similar. In addition, pharmacokinetic analyses in patients with varying degrees of renal impairment did not show significant differences from healthy subjects.« less

Fluoxetine disrupts motivation and GABAergic signaling in adolescent female hamsters.

PubMed

Shannonhouse, John L; DuBois, Dustin W; Fincher, Annette S; Vela, Alejandra M; Henry, Morgan M; Wellman, Paul J; Frye, Gerald D; Morgan, Caurnel

2016-08-01

Initial antidepressant treatment can paradoxically worsen symptoms in depressed adolescents by undetermined mechanisms. Interestingly, antidepressants modulate GABAA receptors, which mediate paradoxical effects of other therapeutic drugs, particularly in females. Although the neuroanatomic site of action for this paradox is unknown, elevated GABAA receptor signaling in the nucleus accumbens can disrupt motivation. We assessed fluoxetine's effects on motivated behaviors in pubescent female hamsters - anhedonia in the reward investigational preference (RIP) test as well as anxiety in the anxiety-related feeding/exploration conflict (AFEC) test. We also assessed accumbal signaling by RT-PCR and electrophysiology. Fluoxetine initially worsened motivated behaviors at puberty, relative to adulthood. It also failed to improve these behaviors as pubescent hamsters transitioned into adulthood. Low accumbal mRNA levels of multiple GABAA receptor subunits and GABA-synthesizing enzyme, GAD67, assessed by RT-PCR, suggested low GABAergic tone at puberty. Nonetheless, rapid fluoxetine-induced reductions of α5GABAA receptor and BDNF mRNA levels at puberty were consistent with age-related differences in GABAergic responses to fluoxetine and disruption of the motivational state. Whole-cell patch clamping of accumbal slices also suggested low GABAergic tone by the low amplitude of miniature inhibitory postsynaptic currents (mIPSCs) at puberty. It also confirmed age-related differences in GABAergic responses to fluoxetine. Specifically, fluoxetine potentiated mIPSC amplitude and frequency at puberty, but attenuated the amplitude during adulthood. These results implicate GABAergic tone and GABAA receptor plasticity in adverse motivational responses and resistance to fluoxetine during adolescence. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of indole-3-carbinol on clonidine-induced neurotoxicity in rats: Impact on oxidative stress, inflammation, apoptosis and monoamine levels.

PubMed

El-Naga, Reem N; Ahmed, Hebatalla I; Abd Al Haleem, Ekram N

2014-09-01

The relationship between inflammation, oxidative stress and the incidence of depression had been well studied. Indole-3-carbinol (I3C), a natural active compound found in cruciferous vegetables, was shown to have anti-oxidant and anti-inflammatory activities. Therefore, the aim of this study was to investigate the potential protective effects of I3C against clonidine-induced depression-like behaviors in rats. Also, the possible mechanisms underlying this neuroprotection; anti-oxidant, anti-inflammatory as well as the modulatory effect on monoamine levels in brain tissues were investigated. I3C was given orally (50mg/kg) daily over 2 weeks starting 7 days before giving clonidine (0.8mg/kg i.p.). Fluoxetine was used as a standard anti-depressant. Open-field test and forced swimming test were carried out to assess exploratory activity and despair behavior, respectively. I3C showed a significant improvement in the behavioral changes induced by clonidine. As indicators of oxidative stress, clonidine induced a significant reduction in GSH and SOD levels as well as an increase lipid peroxidation level. Tissue levels of pro-inflammatory and apoptotic markers were significantly increased in clonidine group. In addition, monoamine levels; noradrenaline and serotonin, showed a drastic decrease in clonidine group. Also, neuron specific enolase (NSE) was significantly elevated in clonidine group. In contrast, I3C pre-treatment significantly attenuated clonidine-induced oxidative stress, inflammation, apoptosis, decreased NSE expression and increased levels of monoamines. Fluoxetine was used as a standard. In conclusion, the findings of this study suggest that I3C protects against clonidine-induced depression. This neuroprotective effect is partially mediated by its anti-oxidant, anti-inflammatory and anti-apoptotic activities as well as elevating monoamines levels. Copyright © 2014 Elsevier Inc. All rights reserved.

Fluoxetine pretreatment enhances neurogenic, angiogenic and immunomodulatory effects of MSCs on experimentally induced diabetic neuropathy.

PubMed

Abdelrahman, Shaimaa A; Samak, Mai A; Shalaby, Sally M

2018-04-23

Being one of the most debilitating complications among diabetic patients, diabetic polyneuropathy (DPN) is a paramount point of continuous research. Stem cell therapies have shown promising results. However, limited cell survival and paracrine activities hinder its transfer from bench to bedside. We designed this study to evaluate fluoxetine-pretreatment technique of mesenchymal stem cells (MSCs) as an approach to enhance their paracrine and immunomodulatory properties in DPN. Effects of fluoxetine treatment of MSCs were tested in vitro. Forty-two adult Wistar male albino rats were utilized, further subdivided into control, diabetic, MSC-treated and fluoxetine-pretreated MSC groups. Sciatic nerve sections were prepared for light and electron microscope examination and immunohistochemical detection of neurofilament (NF) protein. Also, we assessed in vitro survival and paracrine properties of fluoxetine-pretreated MSCs. Real time PCR of BDNF, VEGF, IL-1β, and IL-10 expression in tissue homogenate was performed. Our results showed restoration of normal neuronal histomorphology and ultrastructure, moreover, immunohistochemical expression of anti-neurofilament protein was significantly elevated in MSC-treated groups compared to the diabetic one. Fluoxetine enhanced the MSC survival and their paracrine properties of MSCs in vitro. Furthermore, the fluoxetine-pretreated MSC group revealed a significant elevation of mRNA expression of BDNF (neurotrophic factor) and VEGF (angiogenic factor), denoting ameliorated MSC paracrine properties. Similarly, improved immunomodulatory functions were evident by a significant reduction of interleukin-1β mRNA expression (pro-inflammatory) and a reciprocal significant increase of interleukin-10 (anti-inflammatory). We concluded that fluoxetine-pretreatment of MSCs boosts their survival, paracrine, and immunomodulatory traits and directly influenced neuronal histomorphology. Hence, it presents a promising intervention of diabetic

Chk2 mediates RITA-induced apoptosis.

PubMed

de Lange, J; Verlaan-de Vries, M; Teunisse, A F A S; Jochemsen, A G

2012-06-01

Reactivation of the p53 tumor-suppressor protein by small molecules like Nutlin-3 and RITA (reactivation of p53 and induction of tumor cell apoptosis) is a promising strategy for cancer therapy. The molecular mechanisms involved in the responses to RITA remain enigmatic. Several groups reported the induction of a p53-dependent DNA damage response. Furthermore, the existence of a p53-dependent S-phase checkpoint has been suggested, involving the checkpoint kinase Chk1. We have recently shown synergistic induction of apoptosis by RITA in combination with Nutlin-3, and we observed concomitant Chk2 phosphorylation. Therefore, we investigated whether Chk2 contributes to the cellular responses to RITA. Strikingly, the induction of apoptosis seemed entirely Chk2 dependent. Transcriptional activity of p53 in response to RITA required the presence of Chk2. A partial rescue of apoptosis observed in Noxa knockdown cells emphasized the relevance of p53 transcriptional activity for RITA-induced apoptosis. In addition, we observed an early p53- and Chk2-dependent block of DNA replication upon RITA treatment. Replicating cells seemed more prone to entering RITA-induced apoptosis. Furthermore, the RITA-induced DNA damage response, which was not a secondary effect of apoptosis induction, was strongly attenuated in cells lacking p53 or Chk2. In conclusion, we identified Chk2 as an essential mediator of the cellular responses to RITA.

An analysis of the effects of acute and chronic fluoxetine on extracellular norepinephrine in the rat hippocampus during stress.

PubMed

Page, M E; Abercrombie, E D

1997-06-01

The locus coeruleus (LC) noradrenergic system is activated by a range of arousing and stressful stimuli. The serotonergic inputs to this structure have been shown to attenuate LC activation under some conditions. The present study examined the effect of fluoxetine, a selective serotonin reuptake inhibitor (SSRI) known to be a clinically effective antidepressant, on basal and stress-induced norepinephrine (NE) release. Basal and stress-induced NE efflux in the rat hippocampus were assessed using in vivo microdialysis techniques. The effect of a 30 minute tailpinch stressor on extracellular concentration of NE was compared in rats treated with fluoxetine either once prior to tailpinch or twice daily for 14 days and, respectively, in unhandled controls and vehicle-treated control animals. A single fluoxetine injection prior to tailpinch did not significantly alter the tailpinch-induced increase of extracellular NE as compared to naive controls. However, there was an enhanced NE response to tailpinch in chronic fluoxetine versus chronic vehicle-treated control rats. Thus, acute blockade of 5-HT uptake by fluoxetine does not affect NE release in response to tailpinch stress. Chronic fluoxetine administration, however, results in a potentiated evoked response of the LC-NE system. One action of chronic fluoxetine, which may relate to therapeutic efficacy, is an increase in responsivity of LC neurons.

Hippocampal HDAC4 contributes to postnatal fluoxetine-evoked depression-like behavior.

PubMed

Sarkar, Ambalika; Chachra, Parul; Kennedy, Pamela; Pena, Catherine J; Desouza, Lynette A; Nestler, Eric J; Vaidya, Vidita A

2014-08-01

Fluoxetine treatment in adulthood evokes antidepressant and anxiolytic responses. Paradoxically, postnatal fluoxetine (PNFlx) induces persistent depression- and anxiety-like behaviors. The mechanistic underpinnings of this paradox remain poorly understood. Here, we examined specific molecular changes in the rat hippocampus that accompany perturbed emotionality observed across life following PNFlx. PNFlx-induced hippocampal gene regulation observed in microarray and quantitative PCR studies indicate functional enrichment of genes involved in response to organic substances, protein kinase pathways, DNA binding, and transcriptional repression. We noted specific transcripts (Hdac4, mammalian target of rapamycin (mTOR), Gnai1, protein kinase C gamma (Prkcc), and hyperpolarization-activated cyclic nucleotide-gated channel 1 (Hcn1)) that were consistently dysregulated across life, and selectively influenced by postnatal, but not adult, fluoxetine. Increased histone deacetylase-4 (HDAC4) recruitment, accompanied by decreased activating histone acetylation marks at the mTOR and Gnai1 promoters, indicate a role for HDAC4 in PNFlx-mediated gene dysregulation. Strikingly, coadministration of the HDAC inhibitor sodium butyrate with PNFlx prevented the dysregulation of Hdac4 and mTOR, and the emergence of depression- and anxiety-like behavior. Importantly, we also find that retreatment of PNFlx animals with fluoxetine in adulthood reversed the increased Hdac4 expression, prevented HDAC4 recruitment to the mTOR and Gnai1 promoters, and attenuated the decline in mTOR and Gnai1 expression, coincident with normalization of PNFlx-evoked depression- and anxiety-like behavior. Further, we show that viral-mediated hippocampal overexpression of Hdac4 was sufficient to induce depression-, but not anxiety-, like behavior in adulthood. Our results highlight the unique nature of molecular signatures evoked by PNFlx, and implicate HDAC4 in the dysregulated gene expression and emergence of

Fluoxetine Ameliorates Behavioral and Neuropathological Deficits in a Transgenic Model Mouse of α-synucleinopathy

PubMed Central

Ubhi, Kiren; Inglis, Chandra; Mante, Michael; Patrick, Christina; Adame, Anthony; Spencer, Brian; Rockenstein, Edward; May, Verena; Winkler, Juergen; Masliah, Eliezer

2013-01-01

The term α-synucleinopathies refers to a group of age-related neurological disorders including Parkinson’s disease (PD), Dementia with Lewy Bodies (DLB) and Multiple System Atrophy (MSA) that display an abnormal accumulation of alpha-synuclein (α-syn). In contrast to the neuronal α-syn accumulation observed in PD and DLB, MSA is characterized by a widespread oligodendrocytic α-syn accumulation. Transgenic mice expressing human α-syn under the oligodendrocyte-specific myelin basic protein promoter (MBP1-hαsyn tg mice) model many of the behavioral and neuropathological alterations observed in MSA. Fluoxetine, a selective serotonin reuptake inhibitor, has been shown to be protective in toxin-induced models of PD, however its effects in an in vivo transgenic model of α-synucleinopathy remain unclear. In this context, this study examined the effect of fluoxetine in the MBP1-hαsyn tg mice, a model of MSA. Fluoxetine adminstration ameliorated motor deficits in the MBP1-hαsyn tg mice, with a concomitant decrease in neurodegenerative pathology in the basal ganglia, neocortex and hippocampus. Fluoxetine adminstration also increased levels of the neurotrophic factors, GDNF (glial-derived neurotrophic factor) and BDNF (brain-derived neurotrophic factor) in the MBP1-hαsyn tg mice compared to vehicle-treated tg mice. This fluoxetine-induced increase in GDNF and BDNF protein levels was accompanied by activation of the ERK signaling pathway. The effects of fluoxetine adminstration on myelin and serotonin markers were also examined. Collectively these results indicate that fluoxetine may represent a novel therapeutic intervention for MSA and other neurodegenerative disorders. PMID:22281106

Csk regulates angiotensin II-induced podocyte apoptosis.

PubMed

Zhang, Lu; Ren, Zhilong; Yang, Qian; Ding, Guohua

2016-07-01

Increasing data have shown that angiotensin II (Ang II) perpetuates podocyte injury and promotes progression to end-stage kidney disease. The mechanism underlying Ang II-induced podocyte apoptosis has not been established. C-terminal Src kinase (Csk) is a cytoplasmic kinase that interacts with scaffolding proteins involved in cell growth, adhesion, and polarization, and the role of Csk in regulating cellular apoptosis has gradually attracted attention. This study evaluates the role of Csk in Ang II-induced podocyte apoptosis. In vivo, Wistar rats were randomly subjected to a normal saline or Ang II infusion. In vitro, we exposed differentiated mouse podocytes to Ang II. Ang II increased Csk expression and induced podocyte apoptosis, stimulated Csk translocation and binding to Caveolin-1, and stimulated decreased Fyn pY416, increased Fyn pY529, and nephrin dephosphorylation. Csk knockdown prevented Ang II-induced podocyte apoptosis, reduced Fyn kinase inactivation, and increased the interaction between nephrin and the activated form of Fyn, accompanied by a reduced interaction between Csk and Caveolin-1. These findings indicate that Ang II induces podocyte injury via a Csk-dependent pathway.

Fluoxetine (Prozac) Binding to Serotonin Transporter Is Modulated by Chloride and Conformational Changes

PubMed Central

Tavoulari, Sotiria; Forrest, Lucy R.; Rudnick, Gary

2010-01-01

Serotonin transporter (SERT) is the main target for widely used antidepressant agents. Several of these drugs, including imipramine, citalopram, sertraline, and fluoxetine (Prozac), bound more avidly to SERT in the presence of Cl–. In contrast, Cl– did not enhance cocaine or paroxetine binding. A Cl– binding site recently identified in SERT, and shown to be important for Cl– dependent transport, was also critical for the Cl– dependence of antidepressant affinity. Mutation of the residues contributing to this site eliminated the Cl–-mediated affinity increase for imipramine and fluoxetine. Analysis of ligand docking to a single state of SERT indicated only small differences in the energy of interaction between bound ligands and Cl–. These differences in interaction energy cannot account for the affinity differences observed for Cl– dependence. However, fluoxetine binding led to a conformational change, detected by cysteine accessibility experiments, that was qualitatively different from that induced by cocaine or other ligands. Given the known Cl– requirement for serotonin-induced conformational changes, we propose that Cl– binding facilitates conformational changes required for optimal binding of fluoxetine and other antidepressant drugs. PMID:19641126

Research Advances on Pathways of Nickel-Induced Apoptosis

PubMed Central

Guo, Hongrui; Chen, Lian; Cui, Hengmin; Peng, Xi; Fang, Jing; Zuo, Zhicai; Deng, Junliang; Wang, Xun; Wu, Bangyuan

2015-01-01

High concentrations of nickel (Ni) are harmful to humans and animals. Ni targets a number of organs and produces multiple toxic effects. Apoptosis is important in Ni-induced toxicity of the kidneys, liver, nerves, and immune system. Apoptotic pathways mediated by reactive oxygen species (ROS), mitochondria, endoplasmic reticulum (ER), Fas, and c-Myc participate in Ni-induced cell apoptosis. However, the exact mechanism of apoptosis caused by Ni is still unclear. Understanding the mechanism of Ni-induced apoptosis may help in designing measures to prevent Ni toxicity. PMID:26703593

Visualizing Vpr-Induced G2 Arrest and Apoptosis

PubMed Central

Murakami, Tomoyuki; Aida, Yoko

2014-01-01

Vpr is an accessory protein of human immunodeficiency virus type 1 (HIV-1) with multiple functions. The induction of G2 arrest by Vpr plays a particularly important role in efficient viral replication because the transcriptional activity of the HIV-1 long terminal repeat is most active in G2 phase. The regulation of apoptosis by Vpr is also important for immune suppression and pathogenesis during HIV infection. However, it is not known whether Vpr-induced apoptosis depends on the ability of Vpr to induce G2 arrest, and the dynamics of Vpr-induced G2 arrest and apoptosis have not been visualized. We performed time-lapse imaging to examine the temporal relationship between Vpr-induced G2 arrest and apoptosis using HeLa cells containing the fluorescent ubiquitination-based cell cycle indicator2 (Fucci2). The dynamics of G2 arrest and subsequent long-term mitotic cell rounding in cells transfected with the Vpr-expression vector were visualized. These cells underwent nuclear mis-segregation after prolonged mitotic processes and then entered G1 phase. Some cells subsequently displayed evidence of apoptosis after prolonged mitotic processes and nuclear mis-segregation. Interestingly, Vpr-induced apoptosis was seldom observed in S or G2 phase. Likewise, visualization of synchronized HeLa/Fucci2 cells infected with an adenoviral vector expressing Vpr clearly showed that Vpr arrests the cell cycle at G2 phase, but does not induce apoptosis at S or G2 phase. Furthermore, time-lapse imaging of HeLa/Fucci2 cells expressing SCAT3.1, a caspase-3-sensitive fusion protein, clearly demonstrated that Vpr induces caspase-3-dependent apoptosis. Finally, to examine whether the effects of Vpr on G2 arrest and apoptosis were reversible, we performed live-cell imaging of a destabilizing domain fusion Vpr, which enabled rapid stabilization and destabilization by Shield1. The effects of Vpr on G2 arrest and subsequent apoptosis were reversible. This study is the first to characterize the

Chk2 mediates RITA-induced apoptosis

PubMed Central

de Lange, J; Verlaan-de Vries, M; Teunisse, A F A S; Jochemsen, A G

2012-01-01

Reactivation of the p53 tumor-suppressor protein by small molecules like Nutlin-3 and RITA (reactivation of p53 and induction of tumor cell apoptosis) is a promising strategy for cancer therapy. The molecular mechanisms involved in the responses to RITA remain enigmatic. Several groups reported the induction of a p53-dependent DNA damage response. Furthermore, the existence of a p53-dependent S-phase checkpoint has been suggested, involving the checkpoint kinase Chk1. We have recently shown synergistic induction of apoptosis by RITA in combination with Nutlin-3, and we observed concomitant Chk2 phosphorylation. Therefore, we investigated whether Chk2 contributes to the cellular responses to RITA. Strikingly, the induction of apoptosis seemed entirely Chk2 dependent. Transcriptional activity of p53 in response to RITA required the presence of Chk2. A partial rescue of apoptosis observed in Noxa knockdown cells emphasized the relevance of p53 transcriptional activity for RITA-induced apoptosis. In addition, we observed an early p53- and Chk2-dependent block of DNA replication upon RITA treatment. Replicating cells seemed more prone to entering RITA-induced apoptosis. Furthermore, the RITA-induced DNA damage response, which was not a secondary effect of apoptosis induction, was strongly attenuated in cells lacking p53 or Chk2. In conclusion, we identified Chk2 as an essential mediator of the cellular responses to RITA. PMID:22158418

Subacute Fluoxetine Reduces Signs of Hippocampal Damage Induced by a Single Convulsant Dose of 4-Aminopyridine in Rats.

PubMed

Shiha, Ahmed A; de la Rosa, Rubén Fernández; Delgado, Mercedes; Pozo, Miguel A; García-García, Luis

2017-01-01

Epilepsy is a central disorder associated with neuronal damage and brain hypometabolism. It has been reported that antidepressant drugs show anticonvulsant and neuroprotective effects in different animal models of seizures and epilepsy. The purpose of this study was to investigate the eventual short-term brain impairment induced by a single low convulsant dose of the potassium channel blocker 4-aminopyridine (4-AP) and the eventual neuroprotective effects exerted by fluoxetine, a prototypical selective serotonin (5-hydroxytryptamine; 5-HT) reuptake inhibitor (SSRI). In vivo 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) positron emission tomography (PET) and several histological assessments were carried out in adult male rats after i.p. administration of 3 mg/kg 4-AP for evaluating eventual brain metabolism impairment and signs of hippocampal damage. We also evaluated the effects of a short-term fluoxetine treatment (10 mg/kg, i.p. for 7 days) in this seizure model. [18F]FDG PET analysis revealed no changes in the regional brain metabolism on day 3 after 4-AP injection. The histological assessments revealed signs of damage in the hippocampus, a brain area usually affected by seizures. Thus, reactive gliosis and a significant increase in the expression of caspase-9 were found in the aforementioned brain area. By contrast, we observed no signs of neurodegeneration or neuronal death. Regarding the effects of fluoxetine, this SSRI showed beneficial neurologic effects, since it significantly increased the seizure latency time and reduced the abovementioned 4-AP-induced hippocampal damage markers. Overall, our results point to SSRIs and eventually endogenous 5-HT as neuroprotective agents against convulsant-induced hippocampal damage. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Differential Rearing Alters Forced Swim Test Behavior, Fluoxetine Efficacy, and Post-Test Weight Gain in Male Rats.

PubMed

Arndt, David L; Peterson, Christy J; Cain, Mary E

2015-01-01

Environmental factors play a key role in the etiology of depression. The rodent forced swim test (FST) is commonly used as a preclinical model of depression, with increases in escape-directed behavior reflecting antidepressant effects, and increases in immobility reflecting behavioral despair. Environmental enrichment leads to serotonergic alterations in rats, but it is unknown whether these alterations may influence the efficacy of common antidepressants. Male Sprague-Dawley rats were reared in enriched (EC), standard (SC), or isolated (IC) conditions. Following the rearing period, fluoxetine (10 or 20 mg/kg, i.p.) was administered 23.5 hrs, 5 hrs, and 1 hr before locomotor and FST measures. Following locomotor testing and FST exposure, rats were weighed to assess fluoxetine-, FST-, and environmental condition-induced moderations in weight gain. Results revealed an antidepressant effect of environmental enrichment and a depressant effect of isolation. Regardless of significant fluoxetine effects on locomotor activity, fluoxetine generally decreased swimming and increased immobility in all three environmental conditions, with IC-fluoxetine (10 mg/kg) rats and EC-fluoxetine (20 mg/kg) rats swimming less than vehicle counterparts. Subchronic 20 mg/kg fluoxetine also induced significant weight loss, and differential rearing appeared to moderate weight gain following FST stress. These results suggest that differential rearing has the ability to alter FST behaviors, fluoxetine efficacy, and post-stressor well-being. Moreover, 20 mg/kg fluoxetine, administered subchronically, may lead to atypical effects of those commonly observed in the FST, highlighting the importance and impact of both environmental condition and dosing regimen in common animal models of depression.

Differential Rearing Alters Forced Swim Test Behavior, Fluoxetine Efficacy, and Post-Test Weight Gain in Male Rats

PubMed Central

Arndt, David L.; Peterson, Christy J.; Cain, Mary E.

2015-01-01

Environmental factors play a key role in the etiology of depression. The rodent forced swim test (FST) is commonly used as a preclinical model of depression, with increases in escape-directed behavior reflecting antidepressant effects, and increases in immobility reflecting behavioral despair. Environmental enrichment leads to serotonergic alterations in rats, but it is unknown whether these alterations may influence the efficacy of common antidepressants. Male Sprague-Dawley rats were reared in enriched (EC), standard (SC), or isolated (IC) conditions. Following the rearing period, fluoxetine (10 or 20 mg/kg, i.p.) was administered 23.5 hrs, 5 hrs, and 1 hr before locomotor and FST measures. Following locomotor testing and FST exposure, rats were weighed to assess fluoxetine-, FST-, and environmental condition-induced moderations in weight gain. Results revealed an antidepressant effect of environmental enrichment and a depressant effect of isolation. Regardless of significant fluoxetine effects on locomotor activity, fluoxetine generally decreased swimming and increased immobility in all three environmental conditions, with IC-fluoxetine (10 mg/kg) rats and EC-fluoxetine (20 mg/kg) rats swimming less than vehicle counterparts. Subchronic 20 mg/kg fluoxetine also induced significant weight loss, and differential rearing appeared to moderate weight gain following FST stress. These results suggest that differential rearing has the ability to alter FST behaviors, fluoxetine efficacy, and post-stressor well-being. Moreover, 20 mg/kg fluoxetine, administered subchronically, may lead to atypical effects of those commonly observed in the FST, highlighting the importance and impact of both environmental condition and dosing regimen in common animal models of depression. PMID:26154768

Chronic Fluoxetine Induces Activity Changes in Recovery From Poststroke Anxiety, Depression, and Cognitive Impairment.

PubMed

Vahid-Ansari, Faranak; Albert, Paul R

2018-01-01

Poststroke depression (PSD) is a common outcome of stroke that limits recovery and is only partially responsive to chronic antidepressant treatment. In order to elucidate changes in the cortical-limbic circuitry associated with PSD and its treatment, we examined a novel mouse model of persistent PSD. Focal endothelin-1-induced ischemia of the left medial prefrontal cortex (mPFC) in male C57BL6 mice resulted in a chronic anxiety and depression phenotype. Here, we show severe cognitive impairment in spatial learning and memory in the stroke mice. The behavioral and cognitive phenotypes were reversed by chronic (4-week) treatment with fluoxetine, alone or with voluntary exercise (free-running wheel), but not by exercise alone. To assess chronic cellular activation, FosB + cells were co-labeled for markers of glutamate/pyramidal (VGluT1-3/CaMKIIα), γ-aminobutyric acid (GAD67), and serotonin (TPH). At 6 weeks poststroke versus sham (or 4 days poststroke), left mPFC stroke induced widespread FosB activation, more on the right (contralesional) than on the left side. Stroke activated glutamate cells of the mPFC, nucleus accumbens, amygdala, hippocampus, and raphe serotonin neurons. Chronic fluoxetine balanced bilateral neuronal activity, reducing total FosB and FosB/CamKII + cells (mPFC, nucleus accumbens), and unlike exercise, increasing FosB/GAD67 + cells (septum, amygdala) or both (hippocampus, raphe). In summary, chronic antidepressant but not exercise mediates recovery in this unilateral ischemic PSD model that is associated with region-specific reversal of stroke-induced pyramidal cell hyperactivity and increase in γ-aminobutyric acidergic activity. Targeted brain stimulation to restore brain activity could provide a rational approach for treating clinical PSD.

ATP depletion inhibits glucocorticoid-induced thymocyte apoptosis.

PubMed Central

Stefanelli, C; Bonavita, F; Stanic', I; Farruggia, G; Falcieri, E; Robuffo, I; Pignatti, C; Muscari, C; Rossoni, C; Guarnieri, C; Caldarera, C M

1997-01-01

In quiescent thymocytes, mitochondrial de-energization was not correlated to apoptotic death. In fact, thymocytes treated with oligomycin, a highly specific inhibitor of ATP synthase, alone or with atractyloside to block ATP translocation from the cytoplasm, were alive, even if their mitochondria were depolarized, as revealed by flow cytometry after Rhodamine 123 staining. Furthermore, oligomycin was a powerful inhibitor of apoptosis induced in rat thymocytes by dexamethasone and, to a lesser extent, by the calcium ionophore A23187 and etoposide, but was without effect when apoptosis was induced by staurosporine, and increased cell death in mitogen-treated thymocytes. The inhibition of apoptosis was confirmed by morphological criteria, inhibition of inter-nucleosomal DNA fragmentation and inhibition of the loss of membrane integrity. The anti-apoptotic effect of oligomycin in cells treated with A23187 or etoposide was correlated to the inhibition of protein synthesis, while inhibition of apoptosis induced by dexamethasone, already evident at an oligomycin concentration of 10 ng/ml, was instead strictly correlated to the effect exerted on the cellular ATP level. Thymocyte apoptosis triggered by dexamethasone was blocked or delayed by inhibitors of respiratory-chain uncouplers, inhibitors of ATP synthase and antioxidants: a lasting protection from dexamethasone-induced apoptosis was always correlated to a drastic and rapid reduction in ATP level (31-35% of control), while a delay in the death process was characterized by a moderate decrease in ATP (73-82% of control). Oligomycin inhibited the specific binding of radioactive corticosteroid to thymocyte nuclei, confirming the inhibitory effect of ATP depletion on glucocorticoid binding and suggesting that ATP depletion is a common mediator of the anti-apoptotic action of different effectors in glucocorticoid-induced apoptosis. In conclusion, the reported data indicate that ATP may act as a cellular modulator of some

Fluoxetine ameliorates behavioral and neuropathological deficits in a transgenic model mouse of α-synucleinopathy.

PubMed

Ubhi, Kiren; Inglis, Chandra; Mante, Michael; Patrick, Christina; Adame, Anthony; Spencer, Brian; Rockenstein, Edward; May, Verena; Winkler, Juergen; Masliah, Eliezer

2012-04-01

The term α-synucleinopathies refers to a group of age-related neurological disorders including Parkinson's disease (PD), Dementia with Lewy Bodies (DLB) and Multiple System Atrophy (MSA) that display an abnormal accumulation of alpha-synuclein (α-syn). In contrast to the neuronal α-syn accumulation observed in PD and DLB, MSA is characterized by a widespread oligodendrocytic α-syn accumulation. Transgenic mice expressing human α-syn under the oligodendrocyte-specific myelin basic protein promoter (MBP1-hαsyn tg mice) model many of the behavioral and neuropathological alterations observed in MSA. Fluoxetine, a selective serotonin reuptake inhibitor, has been shown to be protective in toxin-induced models of PD, however its effects in an in vivo transgenic model of α-synucleinopathy remain unclear. In this context, this study examined the effect of fluoxetine in the MBP1-hαsyn tg mice, a model of MSA. Fluoxetine administration ameliorated motor deficits in the MBP1-hαsyn tg mice, with a concomitant decrease in neurodegenerative pathology in the basal ganglia, neocortex and hippocampus. Fluoxetine administration also increased levels of the neurotrophic factors, GDNF (glial-derived neurotrophic factor) and BDNF (brain-derived neurotrophic factor) in the MBP1-hαsyn tg mice compared to vehicle-treated tg mice. This fluoxetine-induced increase in GDNF and BDNF protein levels was accompanied by activation of the ERK signaling pathway. The effects of fluoxetine administration on myelin and serotonin markers were also examined. Collectively these results indicate that fluoxetine may represent a novel therapeutic intervention for MSA and other neurodegenerative disorders. Copyright © 2011 Elsevier Inc. All rights reserved.

Alterations of the Ceramide Metabolism in the Peri-Infarct Cortex Are Independent of the Sphingomyelinase Pathway and Not Influenced by the Acid Sphingomyelinase Inhibitor Fluoxetine.

PubMed

Brunkhorst, R; Friedlaender, F; Ferreirós, N; Schwalm, S; Koch, A; Grammatikos, G; Toennes, S; Foerch, C; Pfeilschifter, J; Pfeilschifter, W

2015-01-01

Ceramides induce important intracellular signaling pathways, modulating proliferation, migration, apoptosis, and inflammation. However, the relevance of the ceramide metabolism in the reconvalescence phase after stroke is unclear. Besides its well-known property as a selective serotonin reuptake inhibitor, fluoxetine has been reported to inhibit the acid sphingomyelinase (ASM), a key regulator of ceramide levels which derives ceramide from sphingomyelin. Furthermore, fluoxetine has shown therapeutic potential in a randomized controlled rehabilitation trial in stroke patients. Our aim was to investigate and modulate ceramide concentrations in the peri-infarct cortex, whose morphological and functional properties correlate with long-term functional outcome in stroke. We show that certain ceramide species are modulated after experimental stroke and that these changes do not result from alterations of ASM activity, but rather from nontranscriptional induction of the ceramide de novo pathway. Unexpectedly, although reducing lesion size, fluoxetine did not improve functional outcome in our model and had no significant influence on ASM activity or the concentration of ceramides. The ceramide metabolism could emerge as a potential therapeutic target in the reconvalescence phase after stroke, as its accumulation in the peri-infarct cortex potentially influences membrane functions as well as signaling events in the tissue essential for neurological recovery.

Perinatal Fluoxetine Exposure Impairs the CO2 Chemoreflex. Implications for Sudden Infant Death Syndrome.

PubMed

Bravo, Karina; Eugenín, Jaime L; Llona, Isabel

2016-09-01

High serotonin levels during pregnancy affect central nervous system development. Whether a commonly used antidepressant such as fluoxetine (a selective serotonin reuptake inhibitor) taken during pregnancy may adversely affect respiratory control in offspring has not been determined. The objective was to determine the effect of prenatal-perinatal fluoxetine exposure on the respiratory neural network in offspring, particularly on central chemoreception. Osmotic minipumps implanted into CF-1 mice on Days 5-7 of pregnancy delivered 7 milligrams per kilogram per day of fluoxetine, achieving plasma levels within the range found in patients. Ventilation was assessed in offspring at postnatal Days 0-40 using head-out body plethysmography. Neuronal activation was evaluated in the raphe nuclei and in the nucleus tractus solitarius by c-Fos immunohistochemistry during normoxic eucapnia and hypercapnia (10% CO2). Respiratory responses to acidosis were evaluated in brainstem slices. Prenatal-perinatal fluoxetine did not affect litter size, birth weight, or the postnatal growth curve. Ventilation under eucapnic normoxic conditions was similar to that of control offspring. Fluoxetine exposure reduced ventilatory responses to hypercapnia at P8-P40 (P < 0.001) but not at P0-P5. At P8, it reduced hypercapnia-induced neuronal activation in raphe nuclei (P < 0.05) and nucleus tractus solitarius (P < 0.01) and the acidosis-induced increase in the respiratory frequency in brainstem slices (P < 0.05). Fluoxetine applied acutely on control slices did not modify their respiratory response to acidosis. We concluded that prenatal-perinatal fluoxetine treatment impairs central respiratory chemoreception during postnatal life. These results are relevant in understanding the pathogenesis of respiratory failures, such as sudden infant death syndrome, associated with brainstem serotonin abnormalities and the failure of respiratory chemoreflexes.

Fluoxetine regulates neurogenesis in vitro through modulation of GSK-3β/β-catenin signaling.

PubMed

Hui, Jiaojie; Zhang, Jianping; Kim, Hoon; Tong, Chang; Ying, Qilong; Li, Zaiwang; Mao, Xuqiang; Shi, Guofeng; Yan, Jie; Zhang, Zhijun; Xi, Guangjun

2014-12-07

It is generally accepted that chronic treatment with antidepressants increases hippocampal neurogenesis, but the molecular mechanisms underlying their effects are unknown. Recently, glycogen synthase kinase-3 beta (GSK-3β)/β-catenin signaling was shown to be involved in the mechanism of how antidepressants might influence hippocampal neurogenesis. The aim of this study was to determine whether GSK-3β/β-catenin signaling is involved in the alteration of neurogenesis as a result of treatment with fluoxetine, a selective serotonin reuptake inhibitor. The mechanisms involved in fluoxetine's regulation of GSK-3β/β-catenin signaling pathway were also examined. Our results demonstrated that fluoxetine increased the proliferation of embryonic neural precursor cells (NPCs) by up-regulating the phosphorylation of Ser9 on GSK-3β and increasing the level of nuclear β-catenin. The overexpression of a stabilized β-catenin protein (ΔN89 β-catenin) significantly increased NPC proliferation, while inhibition of β-catenin expression in NPCs led to a significant decrease in the proliferation and reduced the proliferative effects induced by fluoxetine. The effects of fluoxetine-induced up-regulation of both phosphorylation of Ser9 on GSK-3β and nuclear β-catenin were significantly prevented by the 5-hydroxytryptamine-1A (5-HT1A) receptor antagonist WAY-100635. The results demonstrate that fluoxetine may increase neurogenesis via the GSK-3β/β-catenin signaling pathway that links postsynaptic 5-HT1A receptor activation. © The Author 2015. Published by Oxford University Press on behalf of CINP.

Toxicokinetics, disposition and metabolism of fluoxetine in crabs.

PubMed

Robert, Alexandrine; Schultz, Irvin R; Hucher, Nicolas; Monsinjon, Tiphaine; Knigge, Thomas

2017-11-01

The disposition and metabolism of fluoxetine in the European shore crab and the Dungeness crab were assessed. Crabs received intracardiac doses of either 0.13 μg/kg or 0.5 mg/kg fluoxetine, respectively. In addition, fluoxetine was administered to Metacarcinus cancer by oral gavage at 7.8 mg/kg. The distribution of fluoxetine was quantified in haemolymph and digestive gland for both crabs, as well as brain, muscle, and testis of Carcinus maenas, over 12 days. The metabolite norfluoxetine, was also measured in C. maenas. Fluoxetine was mainly found in lipid rich tissues. Distribution coefficients increased for digestive gland until three days after fluoxetine administration and then decreased until the end of the observations. The highest distribution coefficients were obtained for brain. Norfluoxetine displayed continuously high levels in digestive gland and brain. The strong decrease in fluoxetine and the concomitant increase in norfluoxetine demonstrates that decapod crustaceans metabolise fluoxetine into the more biologically active norfluoxetine. Fluoxetine levels in the haemolymph of M. cancer declined within 20 h, but showed a second peak 25 h later, suggesting remobilisation from tissues sequestering the compound. The steady state volume distribution and the total body clearance of fluoxetine were high, consistent with high diffusion of fluoxetine into the peripheral tissues and biotransformation as an important elimination pathway. Oral administration of fluoxetine prolonged its half-life in M. cancer, but bioavailability was low. These results confirm the high distribution into nervous tissue, extensive biotransformation into the highly active norfluoxetine and a half-life similar to that observed in vertebrates. Copyright © 2017 Elsevier Ltd. All rights reserved.

The role of ARK in stress-induced apoptosis in Drosophila cells

PubMed Central

Zimmermann, Katja C.; Ricci, Jean-Ehrland; Droin, Nathalie M.; Green, Douglas R.

2002-01-01

The molecular mechanisms of apoptosis are highly conserved throughout evolution. The homologs of genes essential for apoptosis in Caenorhabditis elegans and Drosophila melanogaster have been shown to be important for apoptosis in mammalian systems. Although a homologue for CED-4/apoptotic protease-activating factor (Apaf)-1 has been described in Drosophila, its exact function and the role of the mitochondrial pathway in its activation remain unclear. Here, we used the technique of RNA interference to dissect apoptotic signaling pathways in Drosophila cells. Inhibition of the Drosophila CED-4/Apaf-1–related killer (ARK) homologue resulted in pronounced inhibition of stress-induced apoptosis, whereas loss of ARK did not protect the cells from Reaper- or Grim-induced cell death. Reduction of DIAP1 induced rapid apoptosis in these cells, whereas the inhibition of DIAP2 expression did not but resulted in increased sensitivity to stress-induced apoptosis; apoptosis in both cases was prevented by inhibition of ARK expression. Cells in which cytochrome c expression was decreased underwent apoptosis induced by stress stimuli, Reaper or Grim. These results demonstrate the central role of ARK in stress-induced apoptosis, which appears to act independently of cytochrome c. Apoptosis induced by Reaper or Grim can proceed via a distinct pathway, independent of ARK. PMID:11901172

Absorption of Transdermal Fluoxetine Compounded in a Lipoderm Base Compared to Oral Fluoxetine in Client-owned Cats.

PubMed

Eichstadt, Lauren R; Corriveau, Lorraine A; Moore, George E; Knipp, Gregory T; Cooper, Bruce R; Gwin, Wilson E

2017-01-01

The objective of this study was to compare serum concentrations of transdermal fluoxetine compounded in Lipoderm base versus commercially available oral fluoxetine tablets. Sixteen clinically healthy, client-owned cats that were at least one year of age were enrolled. Cats weighed between three and seven kilograms, had no comorbidities, and were behavior medication naïve. Cats were recruited from January 2016 through April 2016. Eight cats were assigned to each medication group based on owner preference. The cats received either oral (1 mg/kg) or transdermal (5 mg/kg; maximum 25 mg daily) fluoxetine compounded in a transdermal base (PCCA Lipoderm), administered daily for 60 days. Serum levels of fluoxetine and norfluoxetine were assessed as a surrogate for relative efficacy. Serum was collected and analyzed by high-performance liquid chromatography-mass spectrometry/mass spectrometry at baseline and days 5, 10, 30, 45, and 60 post-drug start. Adverse effects were monitored during physical exams, speaking with owners, and laboratory analysis of liver function tests at baseline and days 5, 30, and 60 post-drug start. Serum fluoxetine concentrations significantly differed between the treatment groups at days 45 and 60 post-drug start. Norfluoxetine concentrations significantly differed at days 30, 45, and 60 post-drug start. Blood concentrations of fluoxetine and norfluoxetine significantly differed between oral and transdermal routes after 30 days of treatment. Oral fluoxetine concentrations were consistently higher. Transdermal fluoxetine appeared to be well-tolerated, but a lack of knowledge regarding effective blood levels makes it unclear if a clinical effective response would be obtained at the blood concentrations achieved. Copyright© by International Journal of Pharmaceutical Compounding, Inc.

Hyperthermia: an effective strategy to induce apoptosis in cancer cells.

PubMed

Ahmed, Kanwal; Tabuchi, Yoshiaki; Kondo, Takashi

2015-11-01

Heat has been used as a medicinal and healing modality throughout human history. The combination of hyperthermia (HT) with radiation and anticancer agents has been used clinically and has shown positive results to a certain extent. However, the clinical results of HT treatment alone have been only partially satisfactory. Cell death following HT treatment is a function of both temperature and treatment duration. HT induces cancer cell death through apoptosis; the degree of apoptosis and the apoptotic pathway vary in different cancer cell types. HT-induced reactive oxygen species production are responsible for apoptosis in various cell types. However, the underlying mechanism of signal transduction and the genes related to this process still need to be elucidated. In this review, we summarize the molecular mechanism of apoptosis induced by HT, enhancement of heat-induced apoptosis, and the genetic network involved in HT-induced apoptosis.

Fluoxetine ameliorates cognitive impairments induced by chronic cerebral hypoperfusion via down-regulation of HCN2 surface expression in the hippocampal CA1 area in rats.

PubMed

Luo, Pan; Zhang, Xiaoxue; Lu, Yun; Chen, Cheng; Li, Changjun; Zhou, Mei; Lu, Qing; Xu, Xulin; Shen, Guanxin; Guo, Lianjun

2016-01-01

Chronic cerebral hypoperfusion (CCH) causes cognitive impairments and increases the risk of Alzheimer's disease (AD) and vascular dementia (VD) through several biologically plausible pathways, yet the underlying neurobiological mechanisms are still poorly understood. In this study, we investigated whether fluoxetine, a selective serotonin reuptake inhibitor (SSRI), could play a neuroprotective role against chronic cerebral hypoperfusion injury and to clarify underlying mechanisms of its efficacy. Rats were subjected to permanent bilateral occlusion of the common carotid arteries (two-vessel occlusion, 2VO). Two weeks later, rats were treated with 30 mg/kg fluoxetine (intragastric injection, i.g.) for 6 weeks. Cognitive function was evaluated by Morris water maze (MWM) and novel objects recognition (NOR) test. Long-term potentiation (LTP) was used to address the underlying synaptic mechanisms. Western blotting was used to quantify the protein levels. Our results showed that fluoxetine treatment significantly improved the cognitive impairments caused by 2VO, accompanied with a reversion of 2VO-induced inhibitory of LTP. Furthermore, 2VO caused an up-regulation of hyperpolarization-activated cyclic nucleotide-gated channel 2 (HCN2) surface expressions in the hippocampal CA1 area and fluoxetine also effectively recovered the disorder of HCN2 surface expressions, which may be a possible mechanism that fluoxetine treatment ameliorates cognitive impairments in rats with CCH. Copyright © 2015 Elsevier Inc. All rights reserved.

3,3'-diindolylmethane potentiates tumor necrosis factor-related apoptosis-inducing ligand-induced apoptosis of gastric cancer cells.

PubMed

Ye, Yang; Miao, Shuhan; Wang, Yan; Zhou, Jianwei; Lu, Rongzhu

2015-05-01

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) specifically kills cancer cells without destroying the majority of healthy cells. However, numerous types of cancer cell, including gastric cancer cells, tend to be resistant to TRAIL. The bioactive product 3,3'-diindolylmethane (DIM), which is derived from cruciferous vegetables, is also currently recognized as a candidate anticancer agent. In the present study, a Cell Counting Kit 8 cell growth assay and an Annexin V-fluorescein isothiocyanate apoptosis assay were performed to investigate the potentiating effect of DIM on TRAIL-induced apoptosis in gastric cancer cells, and the possible mechanisms of this potentiation. The results obtained demonstrated that, compared with TRAIL or DIM treatment alone, co-treatment with TRAIL (25 or 50 ng/ml) and DIM (10 µmol/l) induced cytotoxic and apoptotic effects in BGC-823 and SGC-7901 gastric cancer cells. Furthermore, western blot analysis revealed that the protein expression levels of death receptor 5 (DR5), CCAAT/enhancer binding protein homologous protein (CHOP) and glucose-regulated protein 78 (GRP78) were upregulated in the co-treated gastric cancer cells. To the best of our knowledge, the present study is the first to provide evidence that DIM sensitizes TRAIL-induced inhibition of proliferation and apoptosis in gastric cancer cells, accompanied by the upregulated expression of DR5, CHOP and GRP78 proteins, which may be involved in endoplasmic reticulum stress mechanisms.

PUMA mediates ER stress-induced apoptosis in portal hypertensive gastropathy

PubMed Central

Tan, S; Wei, X; Song, M; Tao, J; Yang, Y; Khatoon, S; Liu, H; Jiang, J; Wu, B

2014-01-01

Mucosal apoptosis has been demonstrated to be an essential pathological feature in portal hypertensive gastropathy (PHG). p53-upregulated modulator of apoptosis (PUMA) was identified as a BH3-only Bcl-2 family protein that has an essential role in apoptosis induced by a variety of stimuli, including endoplasmic reticulum (ER) stress. However, whether PUMA is involved in mucosal apoptosis in PHG remains unclear, and whether PUMA induces PHG by mediating ER stress remains unknown. The aim of the study is to investigate whether PUMA is involved in PHG by mediating ER stress apoptotic signaling. To identify whether PUMA is involved in PHG by mediating ER stress, gastric mucosal injury and apoptosis were studied in both PHG patients and PHG animal models using PUMA knockout (PUMA-KO) and PUMA wild-type (PUMA-WT) mice. The induction of PUMA expression and ER stress signaling were investigated, and the mechanisms of PUMA-mediated apoptosis were analyzed. GES-1 and SGC7901 cell lines were used to further identify whether PUMA-mediated apoptosis was induced by ER stress in vitro. Epithelial apoptosis and PUMA were markedly induced in the gastric mucosa of PHG patients and mouse PHG models. ER stress had a potent role in the induction of PUMA and apoptosis in PHG models, and the apoptosis was obviously attenuated in PUMA-KO mice. Although the targeted deletion of PUMA did not affect ER stress, mitochondrial apoptotic signaling was downregulated in mice. Meanwhile, PUMA knockdown significantly ameliorated ER stress-induced mitochondria-dependent apoptosis in vitro. These results indicate that PUMA mediates ER stress-induced mucosal epithelial apoptosis through the mitochondrial apoptotic pathway in PHG, and that PUMA is a potentially therapeutic target for PHG. PMID:24625987

The Synergistic Effect of Raloxifene, Fluoxetine, and Bromocriptine Protects Against Pilocarpine-Induced Status Epilepticus and Temporal Lobe Epilepsy.

PubMed

Pottoo, Faheem Hyder; Tabassum, Nahida; Javed, Md Noushad; Nigar, Shah; Rasheed, Rouqia; Khan, Ayash; Barkat, Md Abul; Alam, Md Sabir; Maqbool, Amir; Ansari, Mohammad Azam; Barreto, George E; Ashraf, Ghulam Md

2018-06-07

The present antiepileptic drugs pose several problems in the management of seizures owing to their meager neuroprotective potential, adverse effects on bone, detrimental effects on cognitive function, chronic toxicity, drug interactions, side effects including aggression, agitation, and irritability and sometimes exacerbation of seizures. We followed up progressive preclinical investigation in mice against pilocarpine (PILO)-induced status epilepticus (SE) and temporal lobe epilepsy (TLE). To determine the response of raloxifene (RF) (4 and 8 mg/kg), fluoxetine (FT) (14 and 22 mg/kg), bromocriptine (BC) (6 and 10 mg/kg), and their low-dose combinations, oral treatment was scheduled for 28 days followed by PILO (300 mg/kg, i.p). The response was stalked for intensive behavioral monitoring of convulsions, hippocampal neuropeptide Y (NPY), and oxidative stress discernment along with histomorphological studies. The resultant data confirmed the therapeutic potential of triple drug combination of raloxifene (4 mg/kg) with fluoxetine (14 mg/kg) and bromocriptine (6 mg/kg) compared to monotherapy with raloxifene (4 mg/kg), and bromocriptine (6 mg/kg) as otherwise monotherapy with fluoxetine (14 mg/kg) was ineffective to suppress convulsions; an effect better than sodium valproate (300 mg/kg), a standard AED, was validated. Most profoundly, PILO-induced compensatory increases in hippocampal NPY levels (20.01%), which was escalated (100%) with the triple drug combination. The same pattern of results was superseded for oxidative stress indices and neuronal damage. The results for the first time demonstrate the propitious role of triple drug combination in the management of SE and TLE. Therapeutically, this enhancing profile of drugs fosters a safer and more effective drug-combination regimen. Graphical abstract ᅟ.

Atorvastatin and Fluoxetine Prevent Oxidative Stress and Mitochondrial Dysfunction Evoked by Glutamate Toxicity in Hippocampal Slices.

PubMed

Ludka, Fabiana K; Dal-Cim, Tharine; Binder, Luisa Bandeira; Constantino, Leandra Celso; Massari, Caio; Tasca, Carla I

2017-07-01

Atorvastatin has been shown to exert a neuroprotective action by counteracting glutamatergic toxicity. Recently, we have shown atorvastatin also exerts an antidepressant-like effect that depends on both glutamatergic and serotonergic systems modulation. Excitotoxicity is involved in several brain disorders including depression; thus, it is suggested that antidepressants may target glutamatergic system as a final common pathway. In this study, a comparison of the mechanisms involved in the putative neuroprotective effect of a repetitive atorvastatin or fluoxetine treatment against glutamate toxicity in hippocampal slices was performed. Adult Swiss mice were treated with atorvastatin (10 mg/kg, p.o.) or fluoxetine (10 mg/kg, p.o.), once a day during seven consecutive days. On the eighth day, animals were killed and hippocampal slices were obtained and subjected to an in vitro protocol of glutamate toxicity. An acute treatment of atorvastatin or fluoxetine was not neuroprotective; however, the repeated atorvastatin or fluoxetine treatment prevented the decrease in cellular viability induced by glutamate in hippocampal slices. The loss of cellular viability induced by glutamate was accompanied by increased D-aspartate release, increased reactive oxygen species (ROS) and nitric oxide (NO) production, and impaired mitochondrial membrane potential. Atorvastatin or fluoxetine repeated treatment also presented an antidepressant-like effect in the tail suspension test. Atorvastatin or fluoxetine treatment was effective in protecting mice hippocampal slices from glutamate toxicity by preventing the oxidative stress and mitochondrial dysfunction.

Diazoxide triggers cardioprotection against apoptosis induced by oxidative stress.

PubMed

Ichinose, Masashi; Yonemochi, Hidetoshi; Sato, Toshiaki; Saikawa, Tetsunori

2003-06-01

Although mitochondrial ATP-sensitive potassium (mitoK(ATP)) channels have been reported to reduce the extent of apoptosis, the critical timing of mitoK(ATP) channel opening required to protect myocytes against apoptosis remains unclear. In the present study, we examined whether the mitoK(ATP) channel serves as a trigger of cardioprotection against apoptosis induced by oxidative stress. Apoptosis of cultured neonatal rat cardiomyocytes was determined by flow cytometry (light scatter and propidium iodide/annexin V-FITC fluorescence) and by nuclear staining with Hoechst 33342. Mitochondrial membrane potential (DeltaPsi) was measured by flow cytometry of cells stained with rhodamine-123 (Rh-123). Exposure to H(2)O(2) (500 microM) induced apoptosis, and the percentage of apoptotic cells increased progressively and peaked at 2 h. This H(2)O(2)-induced apoptosis was associated with the loss of DeltaPsi, and the time course of decrease in Rh-123 fluorescence paralleled that of apoptosis. Pretreatment of cardiomyocytes with diazoxide (100 microM), a putative mitoK(ATP) channel opener, for 30 min before exposure to H(2)O(2) elicited transient and mild depolarization of DeltaPsi and consequently suppressed both apoptosis and DeltaPsi loss after 2-h exposure to H(2)O(2). These protective effects of diazoxide were abrogated by the mitoK(ATP) channel blocker 5-hydroxydecanoate (500 microM) but not by the sarcolemmal K(ATP) channel blocker HMR-1098 (30 microM). Our results suggest for the first time that diazoxide-induced opening of mitoK(ATP) channels triggers cardioprotection against apoptosis induced by oxidative stress in rat cardiomyocytes.

Fluoxetine Regulates Neurogenesis In Vitro Through Modulation of GSK-3β/β-Catenin Signaling

PubMed Central

Hui, Jiaojie; Zhang, Jianping; Kim, Hoon; Tong, Chang; Ying, Qilong; Li, Zaiwang; Mao, Xuqiang; Shi, Guofeng; Yan, Jie; Zhang, Zhijun

2015-01-01

Background: It is generally accepted that chronic treatment with antidepressants increases hippocampal neurogenesis, but the molecular mechanisms underlying their effects are unknown. Recently, glycogen synthase kinase-3 beta (GSK-3β)/β-catenin signaling was shown to be involved in the mechanism of how antidepressants might influence hippocampal neurogenesis. Methods: The aim of this study was to determine whether GSK-3β/β-catenin signaling is involved in the alteration of neurogenesis as a result of treatment with fluoxetine, a selective serotonin reuptake inhibitor. The mechanisms involved in fluoxetine’s regulation of GSK-3β/β-catenin signaling pathway were also examined. Results: Our results demonstrated that fluoxetine increased the proliferation of embryonic neural precursor cells (NPCs) by up-regulating the phosphorylation of Ser9 on GSK-3β and increasing the level of nuclear β-catenin. The overexpression of a stabilized β-catenin protein (ΔN89 β-catenin) significantly increased NPC proliferation, while inhibition of β-catenin expression in NPCs led to a significant decrease in the proliferation and reduced the proliferative effects induced by fluoxetine. The effects of fluoxetine-induced up-regulation of both phosphorylation of Ser9 on GSK-3β and nuclear β-catenin were significantly prevented by the 5-hydroxytryptamine-1A (5-HT1A) receptor antagonist WAY-100635. Conclusions: The results demonstrate that fluoxetine may increase neurogenesis via the GSK-3β/β-catenin signaling pathway that links postsynaptic 5-HT1A receptor activation. PMID:25522429

The mitochondria-mediate apoptosis of Lepidopteran cells induced by azadirachtin.

PubMed

Huang, Jingfei; Lv, Chaojun; Hu, Meiying; Zhong, Guohua

2013-01-01

Mitochondria have been shown to play an important role in apoptosis using mammalian cell lines. However, this seems not to be the case in Drosophila, an insect model organism; thus more in-depth studies of insect cell apoptosis are necessary. In the present study, mitochondrial involvement during azadirachtin- and camptothecin-induced apoptosis in Spodoptera frugiperda Sf9 cells (isolated from Spodoptera frugiperda pupal ovarian tissue) was investigated. The results showed that both azadirachtin and camptothecin could induce apoptosis in Sf9 cells. Reactive oxygen species (ROS) generation, activation of mitochondrial permeability transition pores (MPTPs) and loss of mitochondrial membrane potential (MMP) were observed very early during apoptosis and were followed subsequently by the release of cytochrome-c from the mitochondria. Furthermore, the results also revealed that the opening of MPTPs and the loss of MMP induced by azadirachtin could be significantly inhibited by the permeability transition pore (PTP) inhibitor cyclosporin A (CsA), which was used to identify the key role of mitochondria in the apoptosis of Sf9 cells. However, in camptothecin-treated Sf9 cells, CsA could not suppress the opening of MPTPs and the loss of MMP when apoptosis was induced. The data from caspase-3 and caspase-9 activity assays and detection of apoptosis by morphological observation and flow cytometry also uncovered the different effect of CsA on the two botanical apoptosis inducers. Although different mechanisms of apoptosis induction exist, our study revealed that mitochondria play a crucial role in insect cell line apoptosis.

The Mitochondria-Mediate Apoptosis of Lepidopteran Cells Induced by Azadirachtin

PubMed Central

Huang, Jingfei; Lv, Chaojun; Hu, Meiying; Zhong, Guohua

2013-01-01

Mitochondria have been shown to play an important role in apoptosis using mammalian cell lines. However, this seems not to be the case in Drosophila, an insect model organism; thus more in-depth studies of insect cell apoptosis are necessary. In the present study, mitochondrial involvement during azadirachtin- and camptothecin-induced apoptosis in Spodoptera frugiperda Sf9 cells (isolated from Spodoptera frugiperda pupal ovarian tissue) was investigated. The results showed that both azadirachtin and camptothecin could induce apoptosis in Sf9 cells. Reactive oxygen species (ROS) generation, activation of mitochondrial permeability transition pores (MPTPs) and loss of mitochondrial membrane potential (MMP) were observed very early during apoptosis and were followed subsequently by the release of cytochrome-c from the mitochondria. Furthermore, the results also revealed that the opening of MPTPs and the loss of MMP induced by azadirachtin could be significantly inhibited by the permeability transition pore (PTP) inhibitor cyclosporin A (CsA), which was used to identify the key role of mitochondria in the apoptosis of Sf9 cells. However, in camptothecin-treated Sf9 cells, CsA could not suppress the opening of MPTPs and the loss of MMP when apoptosis was induced. The data from caspase-3 and caspase-9 activity assays and detection of apoptosis by morphological observation and flow cytometry also uncovered the different effect of CsA on the two botanical apoptosis inducers. Although different mechanisms of apoptosis induction exist, our study revealed that mitochondria play a crucial role in insect cell line apoptosis. PMID:23516491

Long-term Ameliorative Effects of the Antidepressant Fluoxetine Exposure on Cognitive Deficits in 3 × TgAD Mice.

PubMed

Jin, Li; Gao, Li-Feng; Sun, Dong-Sheng; Wu, Hao; Wang, Qun; Ke, Dan; Lei, Hao; Wang, Jian-Zhi; Liu, Gong-Ping

2017-08-01

Fluoxetine, a selective serotonin reuptake inhibitor, is neuroprotective; therefore, it has been applied to treat some neurodegenerative disorders. For instance, chronic fluoxetine exposure has short-term effects on Alzheimer's disease (AD). However, the long-term ameliorative effects of fluoxetine exposure on AD have not been reported. In the present study, 6-month-old 3 × TgAD mice were treated with fluoxetine for 15 days, and then the influence of fluoxetine was detected at 20 days after the drug withdrawal. We found that chronic fluoxetine treatment ameliorated cognitive deficits of 3 × TgAD mice and increased the volume of the hippocampal CA1 and dentate gyrus (DG) with increased neuron number and dendritic spine density. Meanwhile, fluoxetine exposure also stimulated the long-term potentiation (LTP) in hippocampal DG. The synaptic-related protein expression increased via activation of the cyclic AMP response element binding (CREB) protein/brain-derived neurotrophic factor (BDNF) signaling pathway induced by fluoxetine exposure. Lastly, we found that fluoxetine treatment decreased beta-amyloid (Aβ) levels. These results further certified that fluoxetine may be a potent effective drug for AD.

Mechanism of synergistic action following co-treatment with pramipexole and fluoxetine or sertraline in the forced swimming test in rats.

PubMed

Rogóz, Zofia; Skuza, Grazyna

2006-01-01

The aim of the present study was to examine the effect of combined treatment of male Wistar rats with pramipexole and fluoxetine or sertraline in the forced swimming test. The obtained results showed that co-treatment with pramipexole (0.1 mg/kg) and fluoxetine (10 mg/kg) or sertraline (5 mg/kg) (in doses inactive per se) exhibited antidepressant-like activity in the forced swimming test. Sulpiride (a dopamine D(2/3) receptor antagonist) and WAY 100635 (a 5-HT(1A) receptor antagonist), either being ineffective in the forced swimming test, inhibited the antidepressant-like effect induced by co-administration of pramipexole and fluoxetine or sertraline. However, SCH 23390 (a dopamine D(1) receptor antagonist) only partly did not alter the effect of pramipexole given jointly with antidepressant drugs; on the other hand, S 33084 (a dopamine D(3) receptor antagonist) only partly decreased (in a statistically insignificant manner) that effect. Moreover, progesterone and BD 1047 (a sigma(1) receptor antagonist) counteracted the antidepressant-like effect induced by co-administration of pramipexole and sertraline (but not pramipexole and fluoxetine). In that test, active behavior did not reflect the increases in general activity, since combined administration of pramipexole and fluoxetine or sertraline failed to enhance the locomotor activity of rats. None of the tested drugs (SCH 23390, sulpiride, S 33084, WAY 100635, BD 1047 and progesterone) - alone or in combination with pramipexole and fluoxetine or sertraline - changed locomotor activity. The results described in the present paper indicate that co-administration of pramipexole and fluoxetine or sertraline may induce a more pronounced antidepressive activity than does treatment with pramipexole alone, and that in addition to other mechanisms, dopamine D(2/3) and 5-HT(1A) receptors may contribute to the antidepressant-like activity of pramipexole and fluoxetine or sertraline in the forced swimming test in rats

Ketamine-induced apoptosis in the mouse cerebral cortex follows similar characteristic of physiological apoptosis and can be regulated by neuronal activity.

PubMed

Wang, Qi; Shen, Feng-Yan; Zou, Rong; Zheng, Jing-Jing; Yu, Xiang; Wang, Ying-Wei

2017-06-17

The effects of general anesthetics on inducing neuronal apoptosis during early brain development are well-documented. However, since physiological apoptosis also occurs during this developmental window, it is important to determine whether anesthesia-induced apoptosis targets the same cell population as physiological apoptosis or different cell types altogether. To provide an adequate plane of surgery, ketamine was co-administered with dexmedetomidine. The apoptotic neurons in the mouse primary somatosensory cortex (S1) were quantitated by immunohistochemistry. To explore the effect of neural activity on ketamine-induced apoptosis, the approaches of Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) and an environmental enrichment (EE) were performed. Ketamine-induced apoptosis in S1 is most prominent at postnatal days 5 and 7 (P5 - P7), and becomes insignificant by P12. Physiological and ketamine-induced apoptosis follow similar developmental patterns, mostly comprised of layer V pyramidal neurons at P5 and shifting to mostly layer II to IV GABAergic neurons by P9. Changes in neuronal activity induced by the DREADD system bidirectionally regulated the pattern of ketamine-induced apoptosis, with reduced activity inducing increased apoptosis and shifting the lamination pattern to a more immature form. Importantly, rearing mice in an EE significantly reduced the magnitude of ketamine-induced apoptosis and shifted its developmental pattern to a more mature form. Together, these results demonstrate that lamination pattern and cell-type dependent vulnerability to ketamine-induced apoptosis follow the physiological apoptosis pattern and are age- and activity-dependent. Naturally elevating neuronal activity is a possible method for reducing the adverse effects of general anesthesia.

Tumor Necrosis Factor-related Apoptosis-inducing Ligand (TRAIL)-Troglitazone-induced Apoptosis in Prostate Cancer Cells Involve AMP-activated Protein Kinase*

PubMed Central

Santha, Sreevidya; Viswakarma, Navin; Das, Subhasis; Rana, Ajay; Rana, Basabi

2015-01-01

Prostate cancer (PCa) is one of the most frequently diagnosed cancers in men with limited treatment options for the hormone-resistant forms. Development of novel therapeutic options is critically needed to target advanced forms. Here we demonstrate that combinatorial treatment with the thiazolidinedione troglitazone (TZD) and TNF-related apoptosis-inducing ligand (TRAIL) can induce significant apoptosis in various PCa cells independent of androgen receptor status. Because TZD is known to activate AMP-activated protein kinase (AMPK), we determined whether AMPK is a molecular target mediating this apoptotic cascade by utilizing PCa cell lines stably overexpressing AMPKα1 dominant negative (C4-2-DN) or empty vector (C4-2-EV). Our results indicated a significantly higher degree of apoptosis with TRAIL-TZD combination in C4-2-EV cells compared with C4-2-DN cells. Similarly, results from a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed a larger reduction of viability of C4-2-EV cells compared with C4-2-DN cells when treated with TRAIL-TZD, thus suggesting that C4-2-DN cells were more apoptosis-resistant. Additionally, siRNA-mediated knockdown of endogenous AMPKα1 expression showed a reduction of TRAIL-TZD-induced apoptosis, further confirming the participation of AMPK in mediating this apoptosis. Apoptosis induction by this combinatorial treatment was also associated with a cleavage of β-catenin that was inhibited in both C4-2-DN cells and those cells in which AMPKα1 was knocked down. In addition, time course studies showed an increase in pACCS79 (AMPK target) levels coinciding with the time of apoptosis. These studies indicate the involvement of AMPK in TRAIL-TZD-mediated apoptosis and β-catenin cleavage and suggest the possibility of utilizing AMPK as a therapeutic target in apoptosis-resistant prostate cancer. PMID:26198640

Fluoxetine normalizes disrupted light-induced entrainment, fragmented ultradian rhythms and altered hippocampal clock gene expression in an animal model of high trait anxiety- and depression-related behavior.

PubMed

Schaufler, Jörg; Ronovsky, Marianne; Savalli, Giorgia; Cabatic, Maureen; Sartori, Simone B; Singewald, Nicolas; Pollak, Daniela D

2016-01-01

Disturbances of circadian rhythms are a key symptom of mood and anxiety disorders. Selective serotonin reuptake inhibitors (SSRIs) - commonly used antidepressant drugs - also modulate aspects of circadian rhythmicity. However, their potential to restore circadian disturbances in depression remains to be investigated. The effects of the SSRI fluoxetine on genetically based, depression-related circadian disruptions at the behavioral and molecular level were examined using mice selectively bred for high anxiety-related and co-segregating depression-like behavior (HAB) and normal anxiety/depression behavior mice (NAB). The length of the circadian period was increased in fluoxetine-treated HAB as compared to NAB mice while the number of activity bouts and light-induced entrainment were comparable. No difference in hippocampal Cry2 expression, previously reported to be dysbalanced in untreated HAB mice, was observed, while Per2 and Per3 mRNA levels were higher in HAB mice under fluoxetine treatment. The present findings provide evidence that fluoxetine treatment normalizes disrupted circadian locomotor activity and clock gene expression in a genetic mouse model of high trait anxiety and depression. An interaction between the molecular mechanisms mediating the antidepressant response to fluoxetine and the endogenous regulation of circadian rhythms in genetically based mood and anxiety disorders is proposed.

Verocytotoxin-induced apoptosis of human microvascular endothelial cells.

PubMed

Pijpers, A H; van Setten, P A; van den Heuvel, L P; Assmann, K J; Dijkman, H B; Pennings, A H; Monnens, L A; van Hinsbergh, V W

2001-04-01

The pathogenesis of the epidemic form of hemolytic uremic syndrome is characterized by endothelial cell damage. In this study, the role of apoptosis in verocytotoxin (VT)-mediated endothelial cell death in human glomerular microvascular endothelial cells (GMVEC), human umbilical vein endothelial cells, and foreskin microvascular endothelial cells (FMVEC) was investigated. VT induced apoptosis in GMVEC and human umbilical vein endothelial cells when the cells were prestimulated with the inflammatory mediator tumor necrosis factor-alpha (TNF-alpha). FMVEC displayed strong binding of VT and high susceptibility to VT under basal conditions, which made them suitable for the study of VT-induced apoptosis without TNF-alpha interference. On the basis of functional (flow cytometry and immunofluorescence microscopy using FITC-conjugated annexin V and propidium iodide), morphologic (transmission electron microscopy), and molecular (agarose gel electrophoresis of cellular DNA fragments) criteria, it was documented that VT induced programmed cell death in microvascular endothelial cells in a dose- and time-dependent manner. Furthermore, whereas partial inhibition of protein synthesis by VT was associated with a considerable number of apoptotic cells, comparable inhibition of protein synthesis by cycloheximide was not. This suggests that additional pathways, independent of protein synthesis inhibition, may be involved in VT-mediated apoptosis in microvascular endothelial cells. Specific inhibition of caspases by Ac-Asp-Glu-Val-Asp-CHO, but not by Ac-Tyr-Val-Ala-Asp-CHO, was accompanied by inhibition of VT-induced apoptosis in FMVEC and TNF-alpha-treated GMVEC. These data indicate that VT can induce apoptosis in human microvascular endothelial cells.

Ketamine-induced apoptosis in cultured rat cortical neurons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takadera, Tsuneo; Ishida, Akira; Ohyashiki, Takao

2006-01-15

Recent data suggest that anesthetic drugs cause neurodegeneration during development. Ketamine is frequently used in infants and toddlers for elective surgeries. The purpose of this study is to determine whether glycogen synthase kinase-3 (GSK-3) is involved in ketamine-induced apoptosis. Ketamine increased apoptotic cell death with morphological changes which were characterized by cell shrinkage, nuclear condensation or fragmentation. In addition, insulin growth factor-1 completely blocked the ketamine-induced apoptotic cell death. Ketamine decreased Akt phosphorylation. GSK-3 is known as a downstream target of Akt. The selective inhibitors of GSK-3 prevented the ketamine-induced apoptosis. Moreover, caspase-3 activation was accompanied by the ketamine-induced cellmore » death and inhibited by the GSK-3 inhibitors. These results suggest that activation of GSK-3 is involved in ketamine-induced apoptosis in rat cortical neurons.« less

21 CFR 520.980 - Fluoxetine.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Fluoxetine. 520.980 Section 520.980 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.980 Fluoxetine. (a) Specifications. Each...

Troglitazone induced apoptosis via PPARγ activated POX-induced ROS formation in HT29 cells.

PubMed

Wang, Jing; Lv, XiaoWen; Shi, JiePing; Hu, XiaoSong; DU, YuGuo

2011-08-01

In order to investigate the potential mechanisms in troglitazone-induced apoptosis in HT29 cells, the effects of PPARγ and POX-induced ROS were explored. [3- (4, 5)-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay, Annexin V and PI staining using FACS, plasmid transfection, ROS formation detected by DCFH staining, RNA interference, RT-PCR & RT-QPCR, and Western blotting analyses were employed to investigate the apoptotic effect of troglitazone and the potential role of PPARγ pathway and POX-induced ROS formation in HT29 cells. Troglitazone was found to inhibit the growth of HT29 cells by induction of apoptosis. During this process, mitochondria related pathways including ROS formation, POX expression and cytochrome c release increased, which were inhibited by pretreatment with GW9662, a specific antagonist of PPARγ. These results illustrated that POX upregulation and ROS formation in apoptosis induced by troglitazone was modulated in PPARγ-dependent pattern. Furthermore, the inhibition of ROS and apoptosis after POX siRNA used in troglitazone-treated HT29 cells indicated that POX be essential in the ROS formation and PPARγ-dependent apoptosis induced by troglitazone. The findings from this study showed that troglitazone-induced apoptosis was mediated by POX-induced ROS formation, at least partly, via PPARγ activation. Copyright © 2011 The Editorial Board of Biomedical and Environmental Sciences. Published by Elsevier B.V. All rights reserved.

[Advances in Parvovirus Non-structural Protein NS1 Induced Apoptosis].

PubMed

Tu, Mengyu; Liu, Fei; Chen, Shun; Wang, Mingshu; Cheng, Anchun

2015-11-01

Until now, more than seventeen parvovirus have been reported which can infect mammals and poultries. The infected cells appeared different properties of apoptosis and death, present a typical cytopathic effect. NS1 is a major nonstructural protein of parvovirus, with a conservative structure and function, which plays an important role in the viral life cycle. In addition to the influence on viral replication, the NS1 also participates in apoptosis induced by viruses. Parvovirus induced apoptosis which is mainly mediated by mitochondrial pathway, this review summarized the latest research progresses of parvovirus induced apoptosis.

GSK-3β mediates dexamethasone-induced pancreatic β cell apoptosis

PubMed Central

Guo, Bin; Zhang, Wenjian; Xu, Shiqing; Lou, Jinning; Wang, Shuxia; Men, Xiuli

2015-01-01

Aims Glucocorticoids, such as dexamethasone, are widely used anti-inflammatory drugs. Their use is frequently associated with the development of steroid- associated diabetes. Pancreatic β-cell dysfunction has been suggested to be one of the main causes of steroid-associated diabetes. However, the mechanism is not fully understood. Glycogen synthase kinase-3β (GSK-3β) is a multifunctional serine/threonine kinase and plays an important role in energy metabolism, cell growth and apoptosis. Therefore, the contribution of GSK-3β in dexamethasone-induced pancreatic β-cell apoptosis was determined in the present study. Main Methods The effect of dexamethasone treatment on rat pancreatic β-cell line (INS-1) apoptosis (determined by TUNEL and Flow Cytometry), generation of reactive oxidative stress (ROS), and the phosphorylation status of GSK-3β was determined. The inhibitory effect of GSK-3β inhibitor-lithium chloride (LiCl) on dexamethasone-induced β-cell apoptosis was also evaluated. Key Findings Dexamethasone (0.1 μM) treatment induced INS-1 apoptosis, which was associated with increased GSK-3β activation and increased NOX4-derived ROS generation. Pretreatment of INS-1 with LiCl inhibited dexamethasone induced ROS generation and INS-1 apoptosis. Significance This study provides a new mechanism of Dex induced pancreatic β cell apoptosis and may serve as a new therapeutic option for treating GCs induced diabetes. PMID:26606859

Fluoxetine: a review on evidence based medicine

PubMed Central

Rossi, Andrea; Barraco, Alessandra; Donda, Pietro

2004-01-01

Background Fluoxetine was the first molecule of a new generation of antidepressants, the Selective Serotonin Re-uptake Inhibitors (SSRIs). It is recurrently the paradigm for the development of any new therapy in the treatment of depression. Many controlled studies and meta-analyses were performed on Fluoxetine, to improve the understanding of its real impact in the psychiatric area. The main objective of this review is to assess the quality and the results reported in the meta-analyses published on Fluoxetine. Methods Published articles on Medline, Embase and Cochrane databases reporting meta-analyses were used as data sources for this review. Articles found in the searches were reviewed by 2 independent authors, to assess if these were original meta-analyses. Only data belonging to the most recent and comprehensive meta-analytic studies were included in this review. Results Data, based on a group of 9087 patients, who were included in 87 different randomized clinical trials, confirms that fluoxetine is safe and effective in the treatment of depression from the first week of therapy. Fluoxetine's main advantage over previously available antidepressants (TCAs) was its favorable safety profile, that reduced the incidence of early drop-outs and improved patient's compliance, associated with a comparable efficacy on depressive symptoms. In these patients, Fluoxetine has proven to be more effective than placebo from the first week of therapy. Fluoxetine has shown to be safe and effective in the elderly population, as well as during pregnancy. Furthermore, it was not associated with an increased risk of suicide in the overall evaluation of controlled clinical trials. The meta-analysis available on the use of Fluoxetine in the treatment of bulimia nervosa shows that the drug is as effective as other agents with fewer patients dropping out of treatment. Fluoxetine has demonstrated to be as effective as chlomipramine in the treatment of Obsessive-Compulsive-Disorder (OCD

Overexpression of BAG3 Attenuates Hypoxia-Induced Cardiomyocyte Apoptosis by Inducing Autophagy.

PubMed

Zhang, Jiankai; He, Zhangyou; Xiao, Wenjian; Na, Qingqing; Wu, Tianxiu; Su, Kaixin; Cui, Xiaojun

2016-01-01

Hypoxia is a well-known factor in the promotion of apoptosis, which contributes to the development of numerous cardiac diseases, such as heart failure and myocardial infarction. Inhibiting apoptosis is an important therapeutic strategy for the treatment of related heart diseases caused by ischemia/hypoxic injury. Previous studies have demonstrated that BAG3 plays an important role in cardiomyocyte apoptosis and survival. However, the role of BAG3 in hypoxia-induced cardiomyocyte apoptosis remains to be clarified. Here, we demonstrate that BAG3 is induced by hypoxia stimuli in cultured cardiomyocytes. BAG3 expression level was measured in H9c2 cells treated with hypoxia for 48 h. Cell proliferation and apoptosis were tested using MTT assay and Annexin V FITC-PI staining assay, respectively. The mRNA or protein expression level of BAG3, LC3-I, LC3-II, Atg5, NF-x03BA;B p65 and phosphorylated NF-x03BA;B p65 were assessed by qRT-PCR and western blot assay, respectively. Resluts: Overexpression of BAG3 inhibited cell apoptosis and promoted proliferation in hypoxia-injured H9c2 cells. Furthermore, autophagy and NF-x03BA;B were activated by BAG3 overexpression, and the NF-x03BA;B inhibitor PDTC could inhibit the activation of autophagy induced by BAG3 overexpression. In addition, the autophagy inhibitor 3-MA partly impeded the inhibitory effect of BAG3 on hypoxia-induced cardiomyocyte apoptosis. these results suggested that overexpression of BAG3 promoted cell proliferation and inhibited apoptosis by activating autophagy though the NF-x03BA;B signaling pathway in hypoxia-injured cardiomyocytes. © 2016 The Author(s) Published by S. Karger AG, Basel.

Chronic fluoxetine dissociates contextual from auditory fear memory.

PubMed

Sanders, Jeff; Mayford, Mark

2016-10-06

Fluoxetine is a medication used to treat Major Depressive Disorder and other psychiatric conditions. These experiments studied the effects of chronic fluoxetine treatment on the contextual versus auditory fear memory of mice. We found that chronic fluoxetine treatment of adult mice impaired their contextual fear memory, but spared auditory fear memory. Hippocampal perineuronal nets, which are involved in contextual fear memory plasticity, were unaltered by fluoxetine treatment. These data point to a selective inability to form contextual fear memory as a result of fluoxetine treatment, and they suggest that a blunting of hippocampal-mediated aversive memory may be a therapeutic action for this medication. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Acute fluoxetine modulates emotional processing in young adult volunteers.

PubMed

Capitão, L P; Murphy, S E; Browning, M; Cowen, P J; Harmer, C J

2015-08-01

Fluoxetine is generally regarded as the first-line pharmacological treatment for young people, as it is believed to show a more favourable benefit:risk ratio than other antidepressants. However, the mechanisms through which fluoxetine influences symptoms in youth have been little investigated. This study examined whether acute administration of fluoxetine in a sample of young healthy adults altered the processing of affective information, including positive, sad and anger cues. A total of 35 male and female volunteers aged between 18 and 21 years old were randomized to receive a single 20 mg dose of fluoxetine or placebo. At 6 h after administration, participants completed a facial expression recognition task, an emotion-potentiated startle task, an attentional dot-probe task and the Rapid Serial Visual Presentation. Subjective ratings of mood, anxiety and side effects were also taken pre- and post-fluoxetine/placebo administration. Relative to placebo-treated participants, participants receiving fluoxetine were less accurate at identifying anger and sadness and did not show the emotion-potentiated startle effect. There were no overall significant effects of fluoxetine on subjective ratings of mood. Fluoxetine can modulate emotional processing after a single dose in young adults. This pattern of effects suggests a potential cognitive mechanism for the greater benefit:risk ratio of fluoxetine in adolescent patients.

Bioconcentration of the antidepressant fluoxetine and its effects on the physiological and biochemical status in Daphnia magna.

PubMed

Ding, Jiannan; Zou, Hua; Liu, Qingqing; Zhang, Shanshan; Mamitiana Razanajatovo, Roger

2017-08-01

The aim of this study was to evaluate the bioconcentration potential of fluoxetine and its biological effects in Daphnia magna. After 48h of waterborne exposure, the bioconcentration of fluoxetine in D. magna was determined to be 460.61 and 174.41Lkg -1 for nominal exposure concentrations of 0.5 and 5µgL -1 , respectively. Moreover, various biological endpoints, including physiological responses (filtration and ingestion rates), enzymatic biomarkers related to neurotoxicity [acetylcholinesterase (AChE)] and antioxidant defense [superoxide dismutase (SOD)], and an oxidative stress damage marker [malondialdehyde (MDA)], were assessed. Fluoxetine exposure increased the filtration rate of daphnia, while the ingestion rate was not obviously modified. AChE activity was significantly inhibited, highlighting the neurotoxicity of fluoxetine on D. magna. However, with some alterations in the SOD activity and MDA content, no obvious oxidative damage was observed in D. magna exposed to fluoxetine at the tested concentrations. These results indicate that fluoxetine can be accumulated and consequently induce physiological and biochemical perturbations in D. magna. Copyright © 2017. Published by Elsevier Inc.

Hypoxia-induced p53 modulates both apoptosis and radiosensitivity via AKT.

PubMed

Leszczynska, Katarzyna B; Foskolou, Iosifina P; Abraham, Aswin G; Anbalagan, Selvakumar; Tellier, Céline; Haider, Syed; Span, Paul N; O'Neill, Eric E; Buffa, Francesca M; Hammond, Ester M

2015-06-01

Restoration of hypoxia-induced apoptosis in tumors harboring p53 mutations has been proposed as a potential therapeutic strategy; however, the transcriptional targets that mediate hypoxia-induced p53-dependent apoptosis remain elusive. Here, we demonstrated that hypoxia-induced p53-dependent apoptosis is reliant on the DNA-binding and transactivation domains of p53 but not on the acetylation sites K120 and K164, which, in contrast, are essential for DNA damage-induced, p53-dependent apoptosis. Evaluation of hypoxia-induced transcripts in multiple cell lines identified a group of genes that are hypoxia-inducible proapoptotic targets of p53, including inositol polyphosphate-5-phosphatase (INPP5D), pleckstrin domain-containing A3 (PHLDA3), sulfatase 2 (SULF2), B cell translocation gene 2 (BTG2), cytoplasmic FMR1-interacting protein 2 (CYFIP2), and KN motif and ankyrin repeat domains 3 (KANK3). These targets were also regulated by p53 in human cancers, including breast, brain, colorectal, kidney, bladder, and melanoma cancers. Downregulation of these hypoxia-inducible targets associated with poor prognosis, suggesting that hypoxia-induced apoptosis contributes to p53-mediated tumor suppression and treatment response. Induction of p53 targets, PHLDA3, and a specific INPP5D transcript mediated apoptosis in response to hypoxia through AKT inhibition. Moreover, pharmacological inhibition of AKT led to apoptosis in the hypoxic regions of p53-deficient tumors and consequently increased radiosensitivity. Together, these results identify mediators of hypoxia-induced p53-dependent apoptosis and suggest AKT inhibition may improve radiotherapy response in p53-deficient tumors.

Hypoxia-induced p53 modulates both apoptosis and radiosensitivity via AKT

PubMed Central

Leszczynska, Katarzyna B.; Foskolou, Iosifina P.; Abraham, Aswin G.; Anbalagan, Selvakumar; Tellier, Céline; Haider, Syed; Span, Paul N.; O’Neill, Eric E.; Buffa, Francesca M.; Hammond, Ester M.

2015-01-01

Restoration of hypoxia-induced apoptosis in tumors harboring p53 mutations has been proposed as a potential therapeutic strategy; however, the transcriptional targets that mediate hypoxia-induced p53-dependent apoptosis remain elusive. Here, we demonstrated that hypoxia-induced p53-dependent apoptosis is reliant on the DNA-binding and transactivation domains of p53 but not on the acetylation sites K120 and K164, which, in contrast, are essential for DNA damage–induced, p53-dependent apoptosis. Evaluation of hypoxia-induced transcripts in multiple cell lines identified a group of genes that are hypoxia-inducible proapoptotic targets of p53, including inositol polyphosphate-5-phosphatase (INPP5D), pleckstrin domain–containing A3 (PHLDA3), sulfatase 2 (SULF2), B cell translocation gene 2 (BTG2), cytoplasmic FMR1-interacting protein 2 (CYFIP2), and KN motif and ankyrin repeat domains 3 (KANK3). These targets were also regulated by p53 in human cancers, including breast, brain, colorectal, kidney, bladder, and melanoma cancers. Downregulation of these hypoxia-inducible targets associated with poor prognosis, suggesting that hypoxia-induced apoptosis contributes to p53-mediated tumor suppression and treatment response. Induction of p53 targets, PHLDA3, and a specific INPP5D transcript mediated apoptosis in response to hypoxia through AKT inhibition. Moreover, pharmacological inhibition of AKT led to apoptosis in the hypoxic regions of p53-deficient tumors and consequently increased radiosensitivity. Together, these results identify mediators of hypoxia-induced p53-dependent apoptosis and suggest AKT inhibition may improve radiotherapy response in p53-deficient tumors. PMID:25961455

[Endoplasmic reticulum stress mediates lipopolysaccharide-induced apoptosis in rat hepatocyte].

PubMed

Ji, Ying-Lei; Yan, Jun; Wang, Yan-Sha; Liu, Yi-Chang; Gu, Zhen-Yong

2014-02-01

To investigate the role of endoplasmic reticulum stress (ERS) in lipopolysaccharide (LPS)-induced hepatocyte apoptosis. Cells of the rat hepatocyte line BRL were cultured. The hepatocytes were treated with LPS, ERS inducer thapsigargin (TG), and ERS inhibitor 4-phenylbutyric acid (4-PBA), respectively or in their different combination. The cell viability was measured by MTT assay. The cyto-nuclear morphological changes of apoptosis cells were detected by the fluorescent dye Hoechst 33258. The apoptosis rate was assessed by flow cytometry with Annexin V-FITC/PI double-staining. Expressions of GRP78 as ERS marker protein, CHOP, caspase-12 and cleaved-caspase-3 as ERS related protein were detected by Western blotting. LPS could cause a decrease in cell viability and an increase in apoptosis rate in a dose- and time-dependent manner. The expression of GRP78, CHOP, caspase-12 and cleaved-caspase-3 proteins were significantly increased with LPS treatment. TG led to a marked decrease in cell viability and an increase in apoptosis rate, which aggravated the hepatocyte injury induced by LPS; whereas 4-PBA alleviated LPS-induced apoptosis. ERS mediates LPS-induced hepatocyte injuries, indicating that ERS may play a vital role in the pathogenesis of LPS-induced hepatocyte injuries.

Determination of fluoxetine in pharmaceutical and biological samples based on the silver nanoparticle enhanced fluorescence of fluoxetine-terbium complex.

PubMed

Lotfi, Ali; Manzoori, Jamshid L

2016-11-01

In this study, a simple and sensitive spectrofluorimetric method is presented for the determination of fluoxetine based on the enhancing effect of silver nanoparticles (AgNPs) on the terbium-fluoxetine fluorescence emission. The AgNPs were prepared by a simple reduction method and characterized by UV-Vis spectroscopy and transmission electron microscopy. It was indicated that these AgNPs have a remarkable amplifying effect on the terbium-sensitized fluorescence of fluoxetine. The effects of various parameters such as AgNP and Tb 3+ concentration and the pH of the media were investigated. Under obtained optimal conditions, the fluorescence intensity of the terbium-fluoxetine-AgNP system was enhanced linearly by increasing the concentration of fluoxetine in the range of 0.008 to 19 mg/L. The limit of detection (b + 3s) was 8.3 × 10 -4 mg/L. The interference effects of common species found in real samples were also studied. The method had good linearity, recovery, reproducibility and sensitivity, and was satisfactorily applied for the determination of fluoxetine in tablet formulations, human urine and plasma samples. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

The effect of chronic fluoxetine on social isolation-induced changes on sucrose consumption, immobility behavior, and on serotonin and dopamine function in hippocampus and ventral striatum.

PubMed

Brenes, Juan C; Fornaguera, Jaime

2009-03-02

This study examined the effect of fluoxetine, a selective serotonin (5-HT) reuptake inhibitor, on isolation-induced changes on sucrose consumption and preference, spontaneous open-field activity, forced swimming behavior, and on tissue levels of 5-HT and dopamine (DA) in hippocampus and ventral striatum (VS). Male Sprague-Dawley rats were reared in social isolation or group housing from postnatal day 28. Thirty-two days later, half of the isolated animals were orally treated with fluoxetine (10mg/kg/day) during the following 34 days. At the end of this period, behavior was assessed and afterward ex-vivo tissue samples were obtained. It was found that fluoxetine restored isolation-increased sucrose consumption and immobility behavior, without affecting locomotor activity, which appeared slightly increased in isolated groups both treated and untreated. In the hippocampus, isolation rearing depleted 5-HT contents and increased 3,4-dihydroxyphenylacetic acid (DOPAC) levels, as well as 5-HT and DA turnover. These neurochemical alterations were reversed by fluoxetine. In VS, treated and untreated isolated rats showed higher 5-HT levels than grouped congeners. Although fluoxetine did not affect 5-HT and DA contents in this region, it slightly reversed the alterations in the 5-HT and DA turnover observed in isolated rats. Overall, social isolation impaired incentive and escape motivated behaviors. At the neurochemical level, isolation rearing affected 5-HT rather than DA activity, and this differential effect was more noticeable in hippocampus than in VS. The chronic treatment with fluoxetine during the last month of rearing somewhat prevented these behavioral and neurochemical alterations. Our data suggest that isolation rearing is an appropriate procedure to model some developmental-related alterations underlying depression disorders.

Rapsyn congenital myasthenic syndrome worsened by fluoxetine.

PubMed

Visser, Amy C; Laughlin, Ruple S; Litchy, William J; Benarroch, Eduardo E; Milone, Margherita

2017-01-01

Fluoxetine is a selective serotonin reuptake inhibitor and long-lived open channel blocker of the acetylcholine receptor, often used in the treatment of slow-channel congenital myasthenic syndromes (CMS). We report a 42-year-old woman who had a history of episodic limb weakness that worsened after initiation of fluoxetine for treatment of depression. Genetic testing for CMS revealed a homozygous pathogenic mutation in the rapsyn (RAPSN) gene (p.Asn88Lys). Electrodiagnostic testing was performed before and 1 month after discontinuation of fluoxetine. The 2 Hz repetitive nerve stimulation of the fibular and spinal accessory nerves showed a baseline decrement of 36% and 14%, respectively. One month after discontinuing fluoxetine, the spinal accessory nerve decrement was no longer present, and the decrement in the fibular nerve was improved at 17%. This case demonstrates worsening of both clinical and electrophysiologic findings in a patient with CMS secondary to a RAPSN mutation treated with fluoxetine. Muscle Nerve 55: 131-135, 2017. © 2016 Wiley Periodicals, Inc.

Fluoxetine ameliorates imbalance of redox homeostasis and inflammation in an acute kidney injury model.

PubMed

Aksu, Ugur; Guner, Ibrahim; Yaman, Onur M; Erman, Hayriye; Uzun, Duygu; Sengezer-Inceli, Meliha; Sahin, Ahmet; Yelmen, Nermin; Gelisgen, Remisa; Uzun, Hafize; Sahin, Gulderen

2014-12-01

Ischemia-reperfusion (IR) has been reported to be associated with augmented reactive oxygen radicals and cytokines. Currently, we aimed to examine the influence of fluoxetine, which is already used as a preoperative anxiolytic, in the context of IR induced by occlusion of infrarenal abdominal aorta (60 min of ischemia) and its effects on renal oxidative status, inflammation, renal function, and cellular integrity in reperfusion (120 min post-ischemia). Male rats were randomly assigned as control, IR, and pretreated groups. The pretreated group animals received fluoxetine (20 mg/kg, i.p.) once daily for 3 days. Renal tissue oxidative stress, myeloperoxidase activity, proinflammatory cytokines (tumor necrosis factor-α, interleukin-1β, interleukin-6), histology, and function were assessed. As an anti-inflammatory cytokine, interleukin-10 was also assessed. IR led to a significant increase in lipid hydroperoxide, malondialdehyde, and pro-oxidant antioxidant balance and decrease in superoxide dismutase activity and ferric reducing/antioxidant power level (p < 0.05), but fluoxetine was able to restore these parameters. High concentrations of tumor necrosis factor-α, interleukin-1β, interleukin-6, and myeloperoxidase activity caused by IR were significantly decreased in kidney tissue with fluoxetine. In addition, interleukin-10 levels were high in fluoxetine pretreated group. IR resulted in disrupted cellular integrity, infiltration of tissue with leukocytes, and decreased serum creatinine-urea levels (p < 0.05). Fluoxetine significantly restored impaired redox balance and inflammation parameters of rats subjected to IR to baseline values. This beneficial effect of fluoxetine on redox balance might be addressed to an improvement in renal function.

Oxidative Stress-Responsive Apoptosis Inducing Protein (ORAIP) Plays a Critical Role in High Glucose-Induced Apoptosis in Rat Cardiac Myocytes and Murine Pancreatic β-Cells.

PubMed

Yao, Takako; Fujimura, Tsutomu; Murayama, Kimie; Okumura, Ko; Seko, Yoshinori

2017-10-18

We previously identified a novel apoptosis-inducing humoral factor in the conditioned medium of hypoxic/reoxygenated-cardiac myocytes. We named this novel post-translationally-modified secreted-form of eukaryotic translation initiation factor 5A Oxidative stress-Responsive Apoptosis-Inducing Protein (ORAIP). We confirmed that myocardial ischemia/reperfusion markedly increased plasma ORAIP levels and rat myocardial ischemia/reperfusion injury was clearly suppressed by neutralizing anti-ORAIP monoclonal antibodies (mAbs) in vivo. In this study, to investigate the mechanism of cell injury of cardiac myocytes and pancreatic β-cells involved in diabetes mellitus (DM), we analyzed plasma ORAIP levels in DM model rats and the role of ORAIP in high glucose-induced apoptosis of cardiac myocytes in vitro. We also examined whether recombinant-ORAIP induces apoptosis in pancreatic β-cells. Plasma ORAIP levels in DM rats during diabetic phase were about 18 times elevated as compared with non-diabetic phase. High glucose induced massive apoptosis in cardiac myocytes (66.2 ± 2.2%), which was 78% suppressed by neutralizing anti-ORAIP mAb in vitro. Furthermore, recombinant-ORAIP clearly induced apoptosis in pancreatic β-cells in vitro. These findings strongly suggested that ORAIP plays a pivotal role in hyperglycemia-induced myocardial injury and pancreatic β-cell injury in DM. ORAIP will be a biomarker and a critical therapeutic target for cardiac injury and progression of DM itself.

Fluoxetine for persistent developmental stuttering.

PubMed

Kumar, Amardeep; Balan, Sabish

2007-01-01

Stuttering is a disturbance in the normal fluency and time patterning of speech. Developmental stuttering (DS), with or without associated psychiatric illness, is the most common form and includes all cases with gradual onset in childhood that are not the result of acquired brain damage. Persistent developmental stuttering (PDS) is DS that has not undergone spontaneous or speech therapy-induced remission. Adults in speech therapy behavioral programs will often show regression and even total relapse if they stop practicing. This case report deals with a patient of PDS who responded significantly to treatment with fluoxetine.

Delirium Associated With Fluoxetine Discontinuation: A Case Report.

PubMed

Fan, Kuang-Yuan; Liu, Hsing-Cheng

Withdrawal symptoms on selective serotonin reuptake inhibitor (SSRI) discontinuation have raised clinical attention increasingly. However, delirium is rarely reported in the SSRI discontinuation syndrome. We report a case of delirium developing after fluoxetine discontinuation in a 65-year-old female patient with major depressive disorder. She experienced psychotic depression with limited response to treatment of fluoxetine 40 mg/d and quetiapine 100 mg/d for 3 months. After admission, we tapered fluoxetine gradually in 5 days because of its limited effect. However, delirious pictures developed 2 days after we stopped fluoxetine. Three days later, we added back fluoxetine 10 mg/d. Her delirious features gradually improved, and the clinical presentation turned into previous psychotic depression state. We gradually increased the medication to fluoxetine 60 mg/d and olanzapine 20 mg/d in the following 3 weeks. Her psychotic symptoms decreased, and there has been no delirious picture noted thereafter. Delirium associated with fluoxetine discontinuation is a much rarer complication in SSRI discontinuation syndrome. The symptoms of SSRI discontinuation syndrome may be attributable to a rapid decrease in serotonin availability. In general, the shorter the half-life of any medication, the greater the likelihood patients will experience discontinuation symptoms. Genetic vulnerability might be a potential factor to explain that SSRI discontinuation syndrome also occurred rapidly in people taking long-half-life fluoxetine. The genetic polymorphisms of both pharmacokinetic and pharmacodynamic pathways might be potentially associated with SSRI discontinuation syndrome.

AIRE-induced apoptosis is associated with nuclear translocation of stress sensor protein GAPDH

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liiv, Ingrid, E-mail: ingrid.liiv@ut.ee; Haljasorg, Uku; Kisand, Kai

2012-06-22

Highlights: Black-Right-Pointing-Pointer AIRE induces apoptosis in epithelial cells. Black-Right-Pointing-Pointer CARD domain of AIRE is sufficient for apoptosis induction. Black-Right-Pointing-Pointer AIRE induced apoptosis involves GAPDH translocation to the nuclei. Black-Right-Pointing-Pointer Deprenyl inhibits AIRE induced apoptosis. -- Abstract: AIRE (Autoimmune Regulator) has a central role in the transcriptional regulation of self-antigens in medullary thymic epithelial cells, which is necessary for negative selection of autoreactive T cells. Recent data have shown that AIRE can also induce apoptosis, which may be linked to cross-presentation of these self-antigens. Here we studied AIRE-induced apoptosis using AIRE over-expression in a thymic epithelial cell line as well asmore » doxycycline-inducible HEK293 cells. We show that the HSR/CARD domain in AIRE together with a nuclear localization signal is sufficient to induce apoptosis. In the nuclei of AIRE-positive cells, we also found an increased accumulation of a glycolytic enzyme, glyceraldehyde-3-phosphate (GAPDH) reflecting cellular stress and apoptosis. Additionally, AIRE-induced apoptosis was inhibited with an anti-apoptotic agent deprenyl that blocks GAPDH nitrosylation and nuclear translocation. We propose that the AIRE-induced apoptosis pathway is associated with GAPDH nuclear translocation and induction of NO-induced cellular stress in AIRE-expressing cells.« less

[The mechanism of docetaxel-induced apoptosis in human lung cancer cells].

PubMed

Li, Y; Shi, T; Zhao, W

2000-05-01

To study the mechanism of docetaxel-induced apoptosis. Morphological study, DNA gel electrophoresis, flow cytometry and fluorescin labeled Annexin V to detect apoptosis, RT-PCR to detect the gene related with apoptosis. Human lung cancer A549 cells treated with docetaxel induced cell cycle arrest at G2M phase, leading to apoptosis. The morphology of A549 showed nuclear chromatine condensation and fragmentation. Typical ladder pattern of DNA fragmentation was observed. Sub-G1 peak was found by flow cytometry. Transcription of Fas gene was enhanced, while no change in c-myc and bcl-2 genes. Annexin labeling results revealed the co-existence of cell apoptosis and necrosis in docetaxel-treated A549 cells. Docetaxel induces apoptosis and necrosis of human lung cancer. The induction of apoptosis may be related to expression of Fas.

Leptin receptor deficiency confers resistance to behavioral effects of fluoxetine and desipramine via separable substrates.

PubMed

Guo, M; Lu, X-Y

2014-12-02

Depression is a complex, heterogeneous mental disorder. Currently available antidepressants are only effective in about one-third to one-half of all patients. The mechanisms underlying antidepressant response and treatment resistance are poorly understood. Recent clinical evidence implicates the involvement of leptin in treatment response to antidepressants. In this study, we determined the functional role of the leptin receptor (LepRb) in behavioral responses to the selective serotonergic antidepressant fluoxetine and the noradrenergic antidepressant desipramine. While acute and chronic treatment with fluoxetine or desipramine in wild-type mice elicited antidepressant-like effects in the forced swim test, mice null for LepRb (db/db) displayed resistance to treatment with either fluoxetine or desipramine. Fluoxetine stimulated phosphorylation of Akt(Thr308) and GSK-3β(Ser9) in the hippocampus and prefrontal cortex (PFC) of wild-type mice but not in db/db mice. Desipramine failed to induce measurable changes in Akt, GSK-3β or ERK1/2 phosphorylation in the hippocampus and PFC, as well as hypothalamus of either genotype of mice. Deletion of LepRb specifically from hippocampal and cortical neurons resulted in fluoxetine insensitivity in the forced swim test and tail suspension test while leaving the response to desipramine intact. These results suggest that functional LepRb is critically involved in regulating the antidepressant-like behavioral effects of both fluoxetine and desipramine. The antidepressant effects of fluoxetine but not desipramine are dependent on the presence of functional LepRb in the hippocampus and cortex.

Beneficial effect of fluoxetine treatment aganist psychological stress is mediated by increasing BDNF expression in selected brain areas

PubMed Central

Li, Gongying; Jing, Ping; Liu, Zhidong; Li, Zhiruo; Ma, Hongxia; Tu, Wenzhen; Zhang, Wei; Zhuo, Chuanjun

2017-01-01

SSRI antidepressant fluoxetine is widely used to treat psychological stress related disorders, however the underlying working mechanisms is not fully understood, as SSRIs can rapidly increase the extracellular serotonin levels but it normally takes weeks to reveal their therapeutic effect in the stress-related psychological disorders. Our previous study demonstrated that purely psychological stress without any physic stimuli induces a biphasic change in the expression of brain-derived neurotrophic factor (BDNF), which immediately decrease and then gradually increase after the stress; and that the latter BDNF increase in response to the psychological stress involves the activation of serotonin system. To investigate the role of BDNF in the fluoxetine treatment for stress-related psychological disorders, we examined the mRNA and protein levels of BDNF in the brain of Sprague-Dawley (SD) rats, which were pretreated with fluoxetine at 10 mg/kg or vehicle solution for 14 days, over 24 hour after an acute psychological stress exposure. In situ hybridization and immunohistochemistry were performed to detect the expression of BDNF at different time points in various brain regions after the psychological stress. We found that fluoxetine treatment completely blocked the BDNF decrease induced by the psychological stress, and also enhanced the gradual increase in the expression of BDNF in most of the brain regions except VTA after the psychological stress. The results suggest that the enhancement in BDNF levels induced by chronic fluoxetine treatment mediates the therapeutic effect against psychological stress. PMID:29050222

Direct inhibition of retinoic acid catabolism by fluoxetine.

PubMed

Hellmann-Regen, Julian; Uhlemann, Ria; Regen, Francesca; Heuser, Isabella; Otte, Christian; Endres, Matthias; Gertz, Karen; Kronenberg, Golo

2015-09-01

Recent evidence from animal and human studies suggests neuroprotective effects of the SSRI fluoxetine, e.g., in the aftermath of stroke. The underlying molecular mechanisms remain to be fully defined. Because of its effects on the cytochrome P450 system (CYP450), we hypothesized that neuroprotection by fluoxetine is related to altered metabolism of retinoic acid (RA), whose CYP450-mediated degradation in brain tissue constitutes an important step in the regulation of its site-specific auto- and paracrine actions. Using traditional pharmacological in vitro assays, the effects of fluoxetine on RA degradation were probed in crude synaptosomes from rat brain and human-derived SH-SY5Y cells, and in cultures of neuron-like SH-SY5Y cells. Furthermore, retinoid-dependent effects of fluoxetine on neuronal survival following glutamate exposure were investigated in rat primary neurons cells using specific retinoid receptor antagonists. Experiments revealed dose-dependent inhibition of synaptosomal RA degradation by fluoxetine along with dose-dependent increases in RA levels in cell cultures. Furthermore, fluoxetine's neuroprotective effects against glutamate excitotoxicity in rat primary neurons were demonstrated to partially depend on RA signaling. Taken together, these findings demonstrate for the first time that the potent, pleiotropic antidepressant fluoxetine directly interacts with RA homeostasis in brain tissue, thereby exerting its neuroprotective effects.

Neuroprotective effects of ganoderma lucidum polysaccharides against oxidative stress-induced neuronal apoptosis.

PubMed

Sun, Xin-Zhi; Liao, Ying; Li, Wei; Guo, Li-Mei

2017-06-01

Ganoderma lucidum polysaccharides have protective effects against apoptosis in neurons exposed to ischemia/reperfusion injury, but the mechanisms are unclear. The goal of this study was to investigate the underlying mechanisms of the effects of ganoderma lucidum polysaccharides against oxidative stress-induced neuronal apoptosis. Hydrogen peroxide (H 2 O 2 ) was used to induce apoptosis in cultured cerebellar granule cells. In these cells, ganoderma lucidum polysaccharides remarkably suppressed H 2 O 2 -induced apoptosis, decreased expression of caspase-3, Bax and Bim and increased that of Bcl-2. These findings suggested that ganoderma lucidum polysaccharides regulate expression of apoptosis-associated proteins, inhibit oxidative stress-induced neuronal apoptosis and, therefore, have significant neuroprotective effects.

Raman spectrum reveals the cell cycle arrest of Triptolide-induced leukemic T-lymphocytes apoptosis

NASA Astrophysics Data System (ADS)

Zhang, Daosen; Feng, Yanyan; Zhang, Qinnan; Su, Xin; Lu, Xiaoxu; Liu, Shengde; Zhong, Liyun

2015-04-01

Triptolide (TPL), a traditional Chinese medicine extract, possesses anti-inflammatory and anti-tumor properties. Though some research results have implicated that Triptolide (TPL) can be utilized in the treatment of leukemia, it remains controversial about the mechanism of TPL-induced leukemic T-lymphocytes apoptosis. In this study, combining Raman spectroscopic data, principal component analysis (PCA) and atomic force microscopy (AFM) imaging, both the biochemical changes and morphological changes during TPL-induced cell apoptosis were presented. In contrast, the corresponding data during Daunorubicin (DNR)-induced cell apoptosis was also exhibited. The obtained results showed that Raman spectral changes during TPL-induced cell apoptosis were greatly different from DNR-induced cell apoptosis in the early stage of apoptosis but revealed the high similarity in the late stage of apoptosis. Moreover, above Raman spectral changes were respectively consistent with the morphological changes of different stages during TPL-induced apoptosis or DNR-induced apoptosis, including membrane shrinkage and blebbing, chromatin condensation and the formation of apoptotic bodies. Importantly, it was found that Raman spectral changes with TPL-induced apoptosis or DNR-induced apoptosis were respectively related with the cell cycle G1 phase arrest or G1 and S phase arrest.

Bupivacaine induces apoptosis via ROS in the Schwann cell line.

PubMed

Park, C J; Park, S A; Yoon, T G; Lee, S J; Yum, K W; Kim, H J

2005-09-01

Local anesthetics have been generally accepted as being safe. However, recent clinical trials and basic studies have provided strong evidence for the neurotoxicity of local anesthetics, especially through apoptosis. We hypothesized that local anesthetics cause neural complications through Schwann cell apoptosis. Among local anesthetics tested on the Schwann cell line, RT4-D6P2T, bupivacaine significantly induced cell death, measured by the methyl tetrazolium (MTT) assay, in a dose- (LD50 = 476 microM) and time-dependent manner. The bupivacaine-induced generation of reactive oxygen species (ROS), which was initiated within 5 hrs and preceded the activation of caspase-3 and poly ADP-ribose polymerase (PARP) degradation, was suggested to trigger apoptosis, exhibited by Hoechst 33258 nuclear staining and DNA fragmentation. Furthermore, concomitant block of ROS by anti-oxidants significantly inhibited bupivacaine-induced apoptosis. Among the local anesthetics for peripheral neural blocks, bupivacaine induced apoptosis in the Schwann cell line, which may be associated with ROS production.

Mesolimbic effects of the antidepressant fluoxetine in Holtzman rats, a genetic strain with increased vulnerability to stress

PubMed Central

Padilla, Eimeira; Shumake, Jason; Barrett, Douglas W.; Sheridan, Eva C.; Gonzalez-Lima, F.

2011-01-01

This is the first metabolic mapping study of the effects of fluoxetine after learned helplessness training. Antidepressants are the most commonly prescribed medications, but the regions underlying treatment effects in affectively disordered brains are poorly understood. We hypothesized the antidepressant action of fluoxetine would produce adaptations in mesolimbic regions after two weeks of treatment. We used Holtzman rats, a genetic strain showing susceptibility to novelty-evoked hyperactivity and stress-evoked helplessness, to map regional brain metabolic effects caused by fluoxetine treatment. Animals underwent learned helplessness, and subsequently immobility time was scored in the forced swim test (FST). On the next day, animals began receiving two weeks of fluoxetine (5 mg/kg/day) or vehicle and were retested in the FST at the end of drug treatment. Antidepressant behavioral effects of fluoxetine were analyzed using a ratio of immobility during pre- and post-treatment FST sessions. Brains were analyzed for regional metabolic activity using quantitative cytochrome oxidase histochemistry as in our previous study using congenitally helpless rats. Fluoxetine exerted a protective effect against FST-induced immobility behavior in Holtzman rats. Fluoxetine also caused a significant reduction in the mean regional metabolism of the nucleus accumbens shell and the ventral hippocampus as compared to vehicle-treated subjects. Additional networks affected by fluoxetine treatment included the prefrontal-cingulate cortex and brainstem nuclei linked to depression (e.g. habenula, dorsal raphe and interpeduncular nucleus). We concluded that corticolimbic regions such as the prefrontal-cingulate cortex, nucleus accumbens, ventral hippocampus and key brainstem nuclei represent important contributors to the neural network mediating fluoxetine antidepressant action. PMID:21376019

Paracetamol potentiates the antidepressant-like and anticompulsive-like effects of fluoxetine.

PubMed

Manna, Shyamshree S S; Umathe, Sudhir N

2015-04-01

Recent studies suggest the possible involvement of serotonergic and endocannabinoid systems in analgesic, anxiolytic, and anticonvulsant-like actions of paracetamol. Considering the fact that these systems play intricate roles in affective disorders, we investigated the effects of paracetamol in depression-like and compulsion-like behavior. Swiss mice (20-22 g) were subjected to forced swim, tail suspension, or marble-burying tests after an injection of paracetamol either alone or in the presence of AM251 (a CB1 antagonist), fenclonine (pCPA: a 5-HT synthesis inhibitor), AM404 (anandamide uptake inhibitor) or fluoxetine. Paracetamol dose dependently (50-400 mg/kg) decreased depressive and compulsive behaviors. These effects were comparable to those of fluoxetine (5, 10, or 20 mg/kg) and AM404 (10 or 20 mg/kg). Interestingly, fenclonine pretreatment completely abolished the effects of a 50 mg/kg dose of paracetamol. However, similar effects were not observed in AM251-pretreated mice at the same dose. In contrast, AM251 completely antagonized the effects of the 400 mg/kg dose, which was otherwise partially blocked in fenclonine-treated mice. Similar sets of results were observed with fluoxetine and AM404. Thus, it appears that paracetamol-induced antidepressant-like and anticompulsive effects may, at least partially, involve both the serotonergic and the endocannabinoid system. In addition, coadministration of paracetamol and fluoxetine/AM404 at subeffective doses produced synergistic effects, indicating that subthreshold doses of fluoxetine and paracetamol may enable better management in depression and obsessive-compulsive disorder comorbid patients.

Zinc finger protein 598 inhibits cell survival by promoting UV-induced apoptosis.

PubMed

Yang, Qiaohong; Gupta, Romi

2018-01-19

UV is one of the major causes of DNA damage induced apoptosis. However, cancer cells adopt alternative mechanisms to evade UV-induced apoptosis. To identify factors that protect cancer cells from UV-induced apoptosis, we performed a genome wide short-hairpin RNA (shRNA) screen, which identified Zinc finger protein 598 (ZNF598) as a key regulator of UV-induced apoptosis. Here, we show that UV irradiation transcriptionally upregulates ZNF598 expression. Additionally, ZNF598 knockdown in cancer cells inhibited UV-induced apoptosis. In our study, we observe that ELK1 mRNA level as well as phosphorylated ELK1 levels was up regulated upon UV irradiation, which was necessary for UV irradiation induced upregulation of ZNF598. Cells expressing ELK1 shRNA were also resistant to UV-induced apoptosis, and phenocopy ZNF598 knockdown. Upon further investigation, we found that ZNF598 knockdown inhibits UV-induced apoptotic gene expression, which matches with decrease in percentage of annexin V positive cell. Similarly, ectopic expression of ZNF598 promoted apoptotic gene expression and also increased annexin V positive cells. Collectively, these results demonstrate that ZNF598 is a UV irradiation regulated gene and its loss results in resistance to UV-induced apoptosis.

The psychoactive pollutant fluoxetine compromises antipredator behaviour in fish.

PubMed

Martin, Jake M; Saaristo, Minna; Bertram, Michael G; Lewis, Phoebe J; Coggan, Timothy L; Clarke, Bradley O; Wong, Bob B M

2017-03-01

Pharmaceuticals are increasingly being detected in aquatic ecosystems worldwide. Particularly concerning are pharmaceutical pollutants that can adversely impact exposed wildlife, even at extremely low concentrations. One such contaminant is the widely prescribed antidepressant fluoxetine, which can disrupt neurotransmission and behavioural pathways in wildlife. Despite this, relatively limited research has addressed the behavioural impacts of fluoxetine at ecologically realistic exposure concentrations. Here, we show that 28-day fluoxetine exposure at two ecologically relevant dosages-one representing low surface water concentrations and another representing high effluent flow concentrations-alters antipredator behaviour in Eastern mosquitofish (Gambusia holbrooki). We found that fluoxetine exposure at the lower dosage resulted in increased activity levels irrespective of the presence or absence of a predatory dragonfly nymph (Hemianax papuensis). Additionally, irrespective of exposure concentration, fluoxetine-exposed fish entered the predator 'strike zone' more rapidly. In a separate experiment, fluoxetine exposure reduced mosquitofish freezing behaviour-a common antipredator strategy-following a simulated predator strike, although, in females, this reduction in behaviour was seen only at the lower dosage. Together, our findings suggest that fluoxetine can cause both non-monotonic and sex-dependent shifts in behaviour. Further, they demonstrate that exposure to fluoxetine at environmentally realistic concentrations can alter antipredator behaviour, with important repercussions for organismal fitness. Copyright © 2016 Elsevier Ltd. All rights reserved.

Chalcones Enhance TRAIL-Induced Apoptosis in Prostate Cancer Cells

PubMed Central

Szliszka, Ewelina; Czuba, Zenon P; Mazur, Bogdan; Sedek, Lukasz; Paradysz, Andrzej; Krol, Wojciech

2009-01-01

Chalcones exhibit chemopreventive and antitumor effects. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a naturally occurring anticancer agent that induces apoptosis in cancer cells and is not toxic to normal cells. We examined the cytotoxic and apoptotic effect of five chalcones in combination with TRAIL on prostate cancer cells. The cytotoxicity was evaluated by the MTT and LDH assays. The apoptosis was determined using flow cytometry with annexin V-FITC. Our study showed that all five tested chalcones: chalcone, licochalcone-A, isobavachalcone, xanthohumol, butein markedly augmented TRAIL-mediated apoptosis and cytotoxicity in prostate cancer cells and confirmed the significant role of chalcones in chemoprevention of prostate cancer. PMID:20161998

Apoptosis-induced lymphopenia in sepsis and other severe injuries.

PubMed

Girardot, Thibaut; Rimmelé, Thomas; Venet, Fabienne; Monneret, Guillaume

2017-02-01

Sepsis and other acute injuries such as severe trauma, extensive burns, or major surgeries, are usually followed by a period of marked immunosuppression. In particular, while lymphocytes play a pivotal role in immune response, their functions and numbers are profoundly altered after severe injuries. Apoptosis plays a central role in this process by affecting immune response at various levels. Indeed, apoptosis-induced lymphopenia duration and depth have been associated with higher risk of infection and mortality in various clinical settings. Therapies modulating apoptosis represent an interesting approach to restore immune competence after acute injury, although their use in clinical practice still presents several limitations. After briefly describing the apoptosis process in physiology and during severe injuries, we will explore the immunological consequences of injury-induced lymphocyte apoptosis, and describe associations with clinically relevant outcomes in patients. Therapeutic perspectives targeting apoptosis will also be discussed.

Involvement of Bim in Photofrin-mediated photodynamically induced apoptosis.

PubMed

Wang, Xianwang; He, Xiaobing; Hu, Shujuan; Sun, Anbang; Lu, Chengbiao

2015-01-01

Photodynamic therapy (PDT) is a promising noninvasive technique, which has been successfully applied to the treatment of human cancers. Studies have shown that the Bcl-2 family proteins play important roles in PDT-induced apoptosis. However, whether Bcl-2-interacting mediator of cell death (Bim) is involved in photodynamic treatment remains unknown. In this study, we attempt to determine the effect of Bim on Photofrin photodynamic treatment (PPT)-induced apoptosis in human lung adenocarcinoma ASTC-a-1 cells. The translocation of Bim/Bax of the cells were monitored by laser confocal scanning microscope. The levels of Bim protein and activated caspase-3 in cells were detected by western blot assay. Caspase-3 activities were measured by Caspase-3 Fluorogenic Substrate (Ac-DEVD-AFC) analysis. The induction of apoptosis was detected by Hoechst 33258 and PI staining as well as flow cytometry analysis. The effect of Bim on PPT-induced apoptosis was determined by RNAi. BimL translocated to mitochondria in response to PPT, similar to the downstream pro-apoptotic protein Bax activation. PPT increased the level of Bim and activated caspase-3 in cells and that knockdown of Bim by RNAi significantly protected against caspase-3 activity. PPT-induced apoptosis were suppressed in cells transfected with shRNA-Bim. We demonstrated the involvement of Bim in PPT-induced apoptosis in human ASTC-a-1 lung adenocarcinoma cells and suggested that enhancing Bim activity might be a potential strategy for treating human cancers. © 2015 S. Karger AG, Basel.

Lipopolysaccharide Stimulates Butyric Acid-Induced Apoptosis in Human Peripheral Blood Mononuclear Cells

PubMed Central

Kurita-Ochiai, Tomoko; Fukushima, Kazuo; Ochiai, Kuniyasu

1999-01-01

We previously reported that butyric acid, an extracellular metabolite from periodontopathic bacteria, induced apoptosis in murine thymocytes, splenic T cells, and human Jurkat T cells. In this study, we examined the ability of butyric acid to induce apoptosis in peripheral blood mononuclear cells (PBMC) and the effect of bacterial lipopolysaccharide (LPS) on this apoptosis. Butyric acid significantly inhibited the anti-CD3 monoclonal antibody- and concanavalin A-induced proliferative responses in a dose-dependent fashion. This inhibition of PBMC growth by butyric acid depended on apoptosis in vitro. It was characterized by internucleosomal DNA digestion and revealed by gel electrophoresis followed by a colorimetric DNA fragmentation assay to occur in a concentration-dependent fashion. Butyric acid-induced PBMC apoptosis was accompanied by caspase-3 protease activity but not by caspase-1 protease activity. LPS potentiated butyric acid-induced PBMC apoptosis in a dose-dependent manner. Flow-cytometric analysis revealed that LPS increased the proportion of sub-G1 cells and the number of late-stage apoptotic cells induced by butyric acid. Annexin V binding experiments with fractionated subpopulations of PBMC in flow cytometory revealed that LPS accelerated the butyric acid-induced CD3+-T-cell apoptosis followed by similar levels of both CD4+- and CD8+-T-cell apoptosis. The addition of LPS to PBMC cultures did not cause DNA fragmentation, suggesting that LPS was unable to induce PBMC apoptosis directly. These data suggest that LPS, in combination with butyric acid, potentiates CD3+ PBMC T-cell apoptosis and plays a role in the apoptotic depletion of CD4+ and CD8+ cells. PMID:9864191

Fluoxetine increases plasticity and modulates the proteomic profile in the adult mouse visual cortex

PubMed Central

Ruiz-Perera, L.; Muniz, M.; Vierci, G.; Bornia, N.; Baroncelli, L.; Sale, A.; Rossi, F.M.

2015-01-01

The scarce functional recovery of the adult CNS following injuries or diseases is largely due to its reduced potential for plasticity, the ability to reorganize neural connections as a function of experience. Recently, some new strategies restoring high levels of plasticity in the adult brain have been identified, especially in the paradigmatic model of the visual system. A chronic treatment with the anti-depressant fluoxetine reinstates plasticity in the adult rat primary visual cortex, inducing recovery of vision in amblyopic animals. The molecular mechanisms underlying this effect remain largely unknown. Here, we explored fluoxetine effects on mouse visual cortical plasticity, and exploited a proteomic approach to identify possible candidates mediating the outcome of the antidepressant treatment on adult cortical plasticity. We showed that fluoxetine restores ocular dominance plasticity in the adult mouse visual cortex, and identified 31 differentially expressed protein spots in fluoxetine-treated animals vs. controls. MALDITOF/TOF mass spectrometry identification followed by bioinformatics analysis revealed that these proteins are involved in the control of cytoskeleton organization, endocytosis, molecular transport, intracellular signaling, redox cellular state, metabolism and protein degradation. Altogether, these results indicate a complex effect of fluoxetine on neuronal signaling mechanisms potentially involved in restoring plasticity in the adult brain. PMID:26205348

The Distribution of Fluoxetine and Norfluoxetine in Postmortem Fluids and Tissues

DTIC Science & Technology

2007-06-01

of fluoxetine and nor- fluoxetine in dogs following oral administration of fluoxetine hydrochloride ( Prozac ). J Forensic Sci, 42(5):812-6, 1997. 6...flight crews are submitted to the Federal Aviation Administration’s Civil Aerospace Medical Institute for toxicological analysis. Fluoxetine ( Prozac ...heart muscle, and brain. Specimens were extracted using solid-phase extraction and analyzed by GC/MS. Deuterated fluoxetine and norfluoxetine were

Single fluoxetine treatment before but not after stress prevents stress-induced hippocampal long-term depression and spatial memory retrieval impairment in rats

PubMed Central

Han, Huili; Dai, Chunfang; Dong, Zhifang

2015-01-01

A growing body of evidence has shown that chronic treatment with fluoxetine, a widely prescribed medication for treatment of depression, can affect synaptic plasticity in the adult central nervous system. However, it is not well understood whether acute fluoxetine influences synaptic plasticity, especially on hippocampal CA1 long-term depression (LTD), and if so, whether it subsequently impacts hippocampal-dependent spatial memory. Here, we reported that LTD facilitated by elevated-platform stress in hippocampal slices was completely prevented by fluoxetine administration (10 mg/kg, i.p.) 30 min before stress. The LTD was not, however, significantly inhibited by fluoxetine administration immediately after stress. Similarly, fluoxetine incubation (10 μM) during electrophysiological recordings also displayed no influence on the stress-facilitated LTD. In addition, behavioral results showed that a single fluoxetine treatment 30 min before but not after acute stress fully reversed the impairment of spatial memory retrieval in the Morris water maze paradigm. Taken together, these results suggest that acute fluoxetine treatment only before, but not after stress, can prevent hippocampal CA1 LTD and spatial memory retrieval impairment caused by behavioral stress in adult animals. PMID:26218751

Bim is a crucial regulator of apoptosis induced by Mycobacterium tuberculosis

PubMed Central

Aguiló, N; Uranga, S; Marinova, D; Martín, C; Pardo, J

2014-01-01

Mycobacterium tuberculosis, the causative agent of tuberculosis, induces apoptosis in infected macrophages in vitro and in vivo. However, the molecular mechanism controlling this process is not known. In order to study the involvement of the mitochondrial apoptotic pathway in M. tuberculosis-induced apoptosis, we analysed cell death in M. tuberculosis-infected embryonic fibroblasts (MEFs) derived from different knockout mice for genes involved in this route. We found that apoptosis induced by M. tuberculosis is abrogated in the absence of Bak and Bax, caspase 9 or the executioner caspases 3 and 7. Notably, we show that MEF deficient in the BH3-only BCL-2-interacting mediator of cell death (Bim) protein were also resistant to this process. The relevance of these results has been confirmed in the mouse macrophage cell line J774, where cell transfection with siRNA targeting Bim impaired apoptosis induced by virulent mycobacteria. Notably, only infection with a virulent strain, but not with attenuated ESX-1-defective strains, such as Bacillus Calmette-Guerin and live-attenuated M. tuberculosis vaccine strain MTBVAC, induced Bim upregulation and apoptosis, probably implicating virulence factor early secreted antigenic target 6-kDa protein in this process. Our results suggest that Bim upregulation and apoptosis is mediated by the p38MAPK-dependent pathway. Our findings show that Bim is a master regulator of apoptosis induced by M. tuberculosis. PMID:25032866

Nonylphenol diethoxylate inhibits apoptosis induced in PC12 cells.

PubMed

Liu, Chuang; Sun, Yongkun; Song, Yutong; Saito, Takeshi; Kurasaki, Masaaki

2016-11-01

Nonylphenol and short-chain nonylphenol ethoxylates such as NP 2 EO are present in aquatic environment as wastewater contaminants, and their toxic effects on aquatic species have been reported. Apoptosis has been shown to be induced by serum deprivation or copper treatment. To understand the toxicity of nonylphenol diethoxylate, we investigated the effects of NP 2 EO on apoptosis induced by serum deprivation and copper by using PC12 cell system. Nonylphenol diethoxylate itself showed no toxicity and recovered cell viability from apoptosis. In addition, nonylphenol diethoxylate decreased DNA fragmentation caused by apoptosis in PC12 cells. This phenomenon was confirmed after treating apoptotic PC12 cells with nonylphenol diethoxylate, whereas the cytochrome c release into the cytosol decreased as compared to that in apoptotic cells not treated with nonylphenol diethoxylates. Furthermore, Bax contents in apoptotic cells were reduced after exposure to nonylphenol diethoxylate. Thus, nonylphenol diethoxylate has the opposite effect on apoptosis in PC12 cells compared to nonylphenol, which enhances apoptosis induced by serum deprivation. The difference in structure of the two compounds is hypothesized to be responsible for this phenomenon. These results indicated that nonylphenol diethoxylate has capability to affect cell differentiation and development and has potentially harmful effect on organisms because of its unexpected impact on apoptosis. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1389-1398, 2016. © 2015 Wiley Periodicals, Inc.

Lysophosphatidic acid rescues bone mesenchymal stem cells from hydrogen peroxide-induced apoptosis.

PubMed

Wang, Xian-Yun; Fan, Xue-Song; Cai, Lin; Liu, Si; Cong, Xiang-Feng; Chen, Xi

2015-03-01

The increase of reactive oxygen species in infracted heart significantly reduces the survival of donor mesenchymal stem cells, thereby attenuating the therapeutic efficacy for myocardial infarction. In our previous study, we demonstrated that lysophosphatidic acid (LPA) protects bone marrow-derived mesenchymal stem cells (BMSCs) against hypoxia and serum deprivation-induced apoptosis. However, whether LPA protects BMSCs from H2O2-induced apoptosis was not examined. In this study, we report that H2O2 induces rat BMSC apoptosis whereas LPA pre-treatment effectively protects BMSCs from H2O2-induced apoptosis. LPA protection of BMSC from the induced apoptosis is mediated mostly through LPA3 receptor. Furthermore, we found that membrane G protein Gi2 and Gi3 are involved in LPA-elicited anti-apoptotic effects through activation of ERK1/2- and PI3 K-pathways. Additionally, H2O2 increases levels of type II of light chain 3B (LC3B II), an autophagy marker, and H2O2-induced autophagy thus protected BMSCs from apoptosis. LPA further increases the expression of LC3B II in the presence of H2O2. In contrast, autophagy flux inhibitor bafilomycin A1 has no effect on LPA's protection of BMSC from H2O2-induced apoptosis. Taken together, our data suggest that LPA rescues H2O2-induced apoptosis mainly by interacting with Gi-coupled LPA3, resulting activation of the ERK1/2- and PI3 K/AKT-pathways and inhibition caspase-3 cleavage, and LPA protection of BMSCs against the apoptosis is independent of it induced autophagy.

BEHAVIORAL EFFECTS OF FLUOXETINE IN AN ANIMAL MODEL OF ANXIETY/DEPRESSION ARE MEDIATED BY BOTH NEUROGENESIS-DEPENDENT AND INDEPENDENT MECHANISMS

PubMed Central

David, Denis J.; Samuels, Benjamin Adam; Rainer, Quentin; Wang, Jing-Wen; Marsteller, Douglas; Mendez, Indira; Drew, Michael; Craig, Douglas A.; Guiard, Bruno P.; Guilloux, Jean-Philippe; Artymyshyn, Roman P.; Gardier, Alain M; Gerald, Christophe; Antonijevic, Irina A.; Leonardo, E. David; Hen, René

2009-01-01

SUMMARY Understanding the physiopathology of affective disorders and their treatment relies on the availability of experimental models that accurately mimic aspects of the disease. Here we describe a mouse model of an anxiety/depressive-like state induced by chronic corticosterone treatment. Furthermore, chronic antidepressant treatment reversed the behavioral dysfunctions and the inhibition of hippocampal neurogenesis induced by corticosterone treatment. In corticosterone-treated mice where hippocampal neurogenesis is abolished by X-irradiation, the efficacy of fluoxetine is blocked in some but not all behavioral paradigms, suggesting both neurogenesis-dependent and independent mechanisms of antidepressant actions. Finally, we identified a number of candidate genes, the expression of which is decreased by chronic corticosterone and normalized by chronic fluoxetine treatment selectively in the hypothalamus. Importantly, mice deficient in one of these genes, β-arrestin 2, displayed a reduced response to fluoxetine in multiple tasks, suggesting that β-arrestin signaling is necessary for the antidepressant effects of fluoxetine. PMID:19477151

Fisetin induces apoptosis through mitochondrial apoptosis pathway in human uveal melanoma cells.

PubMed

Wang, Kai; Hu, Dan-Ning; Lin, Hui-Wen; Yang, Wei-En; Hsieh, Yi-Hsien; Chien, Hsiang-Wen; Yang, Shun-Fa

2018-05-01

Fisetin, a diatery flavonoid, been reported that possess anticancer effects in various cancers. The purpose of the study was to investigate the antitumor effects of fisetin in cultured uveal melanoma cell lines and compared with normal retinal pigment epithelial (RPE) cells. MTT assay was used for evaluating cytotoxic effects of fisetin. Flow cytometry study was used for the determination of apoptosis. JC-1 fluorescent reader was used to determine mitochondrial transmembrane potential changes. The results shown that fisetin dose-dependently decreased the cell viability of uveal melanoma cells but not influenced the cell viability of RPE cells. Apoptosis of uveal melanoma cells was induced by fisetin efficiently. Fisetin inhibited antiapoptotic Bcl-2 family proteins and damaged the mitochondrial transmembrane potential. The levels of proapoptotic Bcl-2 proteins, cytochrome c, and various caspase activities were increased by fisetin. In conclusion, fisetin induces apoptosis of uveal melanoma cells selectively and may be a promising agent to be explored for the treatment of uveal melanoma. © 2018 Wiley Periodicals, Inc.

Chronic fluoxetine treatment increases NO bioavailability and calcium-sensitive potassium channels activation in rat mesenteric resistance arteries.

PubMed

Pereira, Camila A; Ferreira, Nathanne S; Mestriner, Fabiola L; Antunes-Rodrigues, José; Evora, Paulo R B; Resstel, Leonardo B M; Carneiro, Fernando S; Tostes, Rita C

2015-10-15

Fluoxetine, a selective serotonin reuptake inhibitor (SSRI), has effects beyond its antidepressant properties, altering, e.g., mechanisms involved in blood pressure and vasomotor tone control. Although many studies have addressed the acute impact of fluoxetine on the cardiovascular system, there is a paucity of information on the chronic vascular effects of this SSRI. We tested the hypothesis that chronic fluoxetine treatment enhances the vascular reactivity to vasodilator stimuli by increasing nitric oxide (NO) signaling and activation of potassium (K+) channels. Wistar rats were divided into two groups: (I) vehicle (water for 21 days) or (II) chronic fluoxetine (10 mg/kg/day in the drinking water for 21 days). Fluoxetine treatment increased endothelium-dependent and independent vasorelaxation (analyzed by mesenteric resistance arteries reactivity) as well as constitutive NO synthase (NOS) activity, phosphorylation of eNOS at Serine1177 and NO production, determined by western blot and fluorescence. On the other hand, fluoxetine treatment did not alter vascular expression of neuronal and inducible NOS or guanylyl cyclase (GC). Arteries from fluoxetine-treated rats exhibited increased relaxation to pinacidil. Increased acetylcholine vasorelaxation was abolished by a calcium-activated K+ channel (KCa) blocker, but not by an inhibitor of KATP channels. On the other hand, vascular responses to Bay 41-2272 and 8-bromo-cGMP were similar between the groups. In conclusion, chronic fluoxetine treatment increases endothelium-dependent and independent relaxation of mesenteric resistance arteries by mechanisms that involve increased eNOS activity, NO generation, and KCa channels activation. These effects may contribute to the cardiovascular effects associated with chronic fluoxetine treatment. Copyright © 2015 Elsevier B.V. All rights reserved.

Effects of acute or repeated paroxetine and fluoxetine treatment on affective behavior in male and female adolescent rats

PubMed Central

Amodeo, Leslie R.; Greenfield, Venuz Y.; Humphrey, Danielle E.; Varela, Veronica; Pipkin, Joseph A.; Eaton, Shannon E.; Johnson, Jelesa D.; Plant, Christopher P.; Harmony, Zachary R.; Wang, Li; Crawford, Cynthia A.

2015-01-01

Rationale The SSRI antidepressant fluoxetine is one of the few drugs that is effective at treating depression in adolescent humans. In contrast, the SSRI paroxetine has limited efficacy and is more at risk for inducing suicidal behavior. Objective The purpose of the present study was to more fully characterize the differential actions of paroxetine and fluoxetine. Methods In Experiment 1, male and female rats were injected with paroxetine (2.5 or 10 mg/kg), fluoxetine (10 mg/kg), or vehicle for 10 days starting on postnatal day (PD) 35, and affective behaviors were assessed using sucrose preference and elevated plus maze tasks. A separate set of rats were used to examine monoamine levels. In Experiment 2, rats were injected with paroxetine (2.5, 5 or 10 mg/kg), fluoxetine (5, 10 or 20 mg/kg), or vehicle during the same time frame as Experiment 1 and anxiety-like behaviors were measured using elevated plus maze, light/dark box, and acoustic startle. Results Repeated SSRI treatment failed to alter sucrose preference, although both paroxetine and fluoxetine reduced time spent in the open arms of the elevated plus maze and light compartment of the light/dark box. Paroxetine, but not fluoxetine, enhanced acoustic startle and interfered with habituation. Serotonin turnover was decreased by both acute and repeated fluoxetine treatment but unaltered by paroxetine administration. Discussion These results show that repeated treatment with paroxetine and fluoxetine has dissociable actions in adolescent rats. In particular, paroxetine, but not fluoxetine, increases acoustic startle at low doses and may increase sensitivity to environmental stressors. PMID:26141193

Effects of acute or repeated paroxetine and fluoxetine treatment on affective behavior in male and female adolescent rats.

PubMed

Amodeo, Leslie R; Greenfield, Venuz Y; Humphrey, Danielle E; Varela, Veronica; Pipkin, Joseph A; Eaton, Shannon E; Johnson, Jelesa D; Plant, Christopher P; Harmony, Zachary R; Wang, Li; Crawford, Cynthia A

2015-10-01

The SSRI antidepressant fluoxetine is one of the few drugs that is effective at treating depression in adolescent humans. In contrast, the SSRI paroxetine has limited efficacy and is more at risk for inducing suicidal behavior. The purpose of the present study was to more fully characterize the differential actions of paroxetine and fluoxetine. In experiment 1, male and female rats were injected with paroxetine (2.5 or 10 mg/kg), fluoxetine (10 mg/kg), or vehicle for 10 days starting on postnatal day (PD) 35, and affective behaviors were assessed using sucrose preference and elevated plus maze tasks. A separate set of rats were used to examine monoamine levels. In experiment 2, rats were injected with paroxetine (2.5, 5, or 10 mg/kg), fluoxetine (5, 10, or 20 mg/kg), or vehicle during the same time frame as experiment 1, and anxiety-like behaviors were measured using elevated plus maze, light/dark box, and acoustic startle. Repeated SSRI treatment failed to alter sucrose preference, although both paroxetine and fluoxetine reduced time spent in the open arms of the elevated plus maze and light compartment of the light/dark box. Paroxetine, but not fluoxetine, enhanced acoustic startle and interfered with habituation. Serotonin turnover was decreased by both acute and repeated fluoxetine treatment but unaltered by paroxetine administration. These results show that repeated treatment with paroxetine and fluoxetine has dissociable actions in adolescent rats. In particular, paroxetine, but not fluoxetine, increases acoustic startle at low doses and may increase sensitivity to environmental stressors.

Cytoprotection by fructose and other ketohexoses during bile salt-induced apoptosis of hepatocytes.

PubMed

Zeid, I M; Bronk, S F; Fesmier, P J; Gores, G J

1997-01-01

Toxic bile salts cause hepatocyte necrosis at high concentrations and apoptosis at lower concentrations. Although fructose prevents bile salt-induced necrosis, the effect of fructose on bile salt-induced apoptosis is unclear. Our aim was to determine if fructose also protects against bile salt-induced apoptosis. Fructose inhibited glycochenodeoxycholate (GCDC)-induced apoptosis in a concentration-dependent manner with a maximum inhibition of 72% +/- 10% at 10 mmol/L. First, we determined if fructose inhibited apoptosis by decreasing adenosine triphosphate (ATP) and intracellular pH (pHi). Although fructose decreased ATP to <25% of basal values, oligomycin (an ATP synthase inhibitor) did not inhibit apoptosis despite decreasing ATP to similar values. Fructose (10 mmol/L) decreased intracellular pH (pHi) by 0.2 U. However, extracellular acidification (pH 6.8), which decreased hepatocyte pHi 0.35 U and is known to inhibit necrosis, actually potentiated apoptosis 1.6-fold. Fructose cytoprotection also could not be explained by induction of bcl-2 transcription or metal chelation. Because we could not attribute fructose cytoprotection to metabolic effects, alterations in the expression of bcl-2, or metal chelation, we next determined if the poorly metabolized ketohexoses, tagatose and sorbose, also inhibited apoptosis; unexpectedly, both ketohexoses inhibited apoptosis. Because bile salt-induced apoptosis and necrosis are inhibited by fructose, these data suggest that similar processes initiate bile salt-induced hepatocyte necrosis and apoptosis. In contrast, acidosis, which inhibits necrosis, potentiates apoptosis. Thus, ketohexose-sensitive pathways appear to initiate both bile salt-induced cell apoptosis and necrosis, whereas dissimilar, pH-sensitive, effector mechanisms execute these two different cell death processes.

Ursodeoxycholic Acid Induces Death Receptor-mediated Apoptosis in Prostate Cancer Cells

PubMed Central

Lee, Won Sup; Jung, Ji Hyun; Panchanathan, Radha; Yun, Jeong Won; Kim, Dong Hoon; Kim, Hye Jung; Kim, Gon Sup; Ryu, Chung Ho; Shin, Sung Chul; Hong, Soon Chan; Choi, Yung Hyun; Jung, Jin-Myung

2017-01-01

Background Bile acids have anti-cancer properties in a certain types of cancers. We determined anticancer activity and its underlying molecular mechanism of ursodeoxycholic acid (UDCA) in human DU145 prostate cancer cells. Methods Cell viability was measured with an MTT assay. UDCA-induced apoptosis was determined with flow cytometric analysis. The expression levels of apoptosis-related signaling proteins were examined with Western blotting. Results UDCA treatment significantly inhibited cell growth of DU145 in a dose-dependent manner. It induced cellular shrinkage and cytoplasmic blebs and accumulated the cells with sub-G1 DNA contents. Moreover, UDCA activated caspase 8, suggesting that UDCA-induced apoptosis is associated with extrinsic pathway. Consistent to this finding, UDCA increased the expressions of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptor, death receptor 4 (DR4) and death receptor 5 (DR5), and TRAIL augmented the UDCA-induced cell death in DU145 cells. In addition, UDCA also increased the expressions of Bax and cytochrome c and decreased the expression of Bcl-xL in DU145 cells. This finding suggests that UDCA-induced apoptosis may be involved in intrinsic pathway. Conclusions UDCA induces apoptosis via extrinsic pathway as well as intrinsic pathway in DU145 prostate cancer cells. UDCA may be a promising anti-cancer agent against prostate cancer. PMID:28382282

Calpain mediates AIF-regulated caspase-independent pathway in cisplatin-induced apoptosis

NASA Astrophysics Data System (ADS)

Liu, Lei; Xing, Da; Chen, Wei R.

2007-11-01

Mitochondrial apoptosis inducing factor (AIF) on activation can translocate to the nucleus and induce cell death via caspase-independent pathway in cisplatin-induced apoptosis. Yet the precise signal transduction pathway(s) which regulates AIF-induced apoptotic pathway still remains poorly understood. In this study, we investigated the molecular mechanism of AIF release and redistribution in cisplatin-induced apoptosis in living ASTC-a-1 cells, as assessed by real-time anlysis. Herein, We report that during cisplatin-induced apoptosis, calpain activation, as measured in intact cells by a fluorescent substrates, is an early event, taking place well before AIF release and caspase-3 activation. Confocal imaging of the cells transfected with AIF-GFP demonstrated that AIF release occurred about 9 h after cisplatin treatment. The event proceeded progressively over time, coinciding with a nuclear translocation and lasting for more than 2 hours. AIF release and redistribution were effectively inhibited in samples co-treated with calpeptin and PD150606, two selective calpain inhibitors. Therefore, our results clearly show the kinetics of AIF release and redistribution in cisplatin-induced apoptosis in living ASTC-a-1 cells, and calpain played a crucial role in these events.

Bcl-2 prevents loss of mitochondria in CCCP-induced apoptosis.

PubMed

de Graaf, Aniek O; van den Heuvel, Lambert P; Dijkman, Henry B P M; de Abreu, Ronney A; Birkenkamp, Kim U; de Witte, Theo; van der Reijden, Bert A; Smeitink, Jan A M; Jansen, Joop H

2004-10-01

Bcl-2 family proteins regulate apoptosis at the level of mitochondria. To examine the mechanism of Bcl-2 function, we investigated the effects of the protonophore carbonyl cyanide m-chlorophenyl hydrazone (CCCP) on two hematopoietic cell lines and Bcl-2 overexpressing transfectants. CCCP directly interferes with mitochondrial function and induces apoptosis. We show that Bcl-2 inhibits apoptosis and that the antiapoptotic effect of Bcl-2 takes place upstream of caspase activation and nuclear changes associated with apoptosis, since these were markedly inhibited in cells overexpressing Bcl-2. Bcl-2 does not prevent the decrease in mitochondrial membrane potential nor the alterations in cellular ATP content induced by CCCP in FL5.12 and Jurkat cells. A higher number of mitochondria was observed in untreated Bcl-2 transfected cells compared to parental cells, as shown by electron microscopy. Exposure to CCCP induced a dramatic decrease in the number of mitochondria and severely disrupted mitochondrial ultrastructure, with apparent swelling and loss of cristae in parental cells. Bcl-2 clearly diminished the disruption of mitochondrial structure and preserved a higher number of mitochondria. These data suggest that CCCP induces apoptosis by structural disruption of mitochondria and that Bcl-2 prevents apoptosis and mitochondrial degeneration by preserving mitochondrial integrity.

Neem oil limonoids induces p53-independent apoptosis and autophagy

PubMed Central

Chandra, Dhyan

2012-01-01

Azadirachta indica, commonly known as neem, has a wide range of medicinal properties. Neem extracts and its purified products have been examined for induction of apoptosis in multiple cancer cell types; however, its underlying mechanisms remain undefined. We show that neem oil (i.e., neem), which contains majority of neem limonoids including azadirachtin, induced apoptotic and autophagic cell death. Gene silencing demonstrated that caspase cascade was initiated by the activation of caspase-9, whereas caspase-8 was also activated late during neem-induced apoptosis. Pretreatment of cancer cells with pan caspase inhibitor, z-VAD inhibited activities of both initiator caspases (e.g., caspase-8 and -9) and executioner caspase-3. Neem induced the release of cytochrome c and apoptosis-inducing factor (AIF) from mitochondria, suggesting the involvement of both caspase-dependent and AIF-mediated apoptosis. p21 deficiency caused an increase in caspase activities at lower doses of neem, whereas p53 deficiency did not modulate neem-induced caspase activation. Additionally, neem treatment resulted in the accumulation of LC3-II in cancer cells, suggesting the involvement of autophagy in neem-induced cancer cell death. Low doses of autophagy inhibitors (i.e., 3-methyladenine and LY294002) did not prevent accumulation of neem-induced LC3-II in cancer cells. Silencing of ATG5 or Beclin-1 further enhanced neem-induced cell death. Phosphoinositide 3-kinase (PI3K) or autophagy inhibitors increased neem-induced caspase-3 activation and inhibition of caspases enhanced neem-induced autophagy. Together, for the first time, we demonstrate that neem induces caspase-dependent and AIF-mediated apoptosis, and autophagy in cancer cells. PMID:22915764

Neem oil limonoids induces p53-independent apoptosis and autophagy.

PubMed

Srivastava, Pragya; Yadav, Neelu; Lella, Ravi; Schneider, Andrea; Jones, Anthony; Marlowe, Timothy; Lovett, Gabrielle; O'Loughlin, Kieran; Minderman, Hans; Gogada, Raghu; Chandra, Dhyan

2012-11-01

Azadirachta indica, commonly known as neem, has a wide range of medicinal properties. Neem extracts and its purified products have been examined for induction of apoptosis in multiple cancer cell types; however, its underlying mechanisms remain undefined. We show that neem oil (i.e., neem), which contains majority of neem limonoids including azadirachtin, induced apoptotic and autophagic cell death. Gene silencing demonstrated that caspase cascade was initiated by the activation of caspase-9, whereas caspase-8 was also activated late during neem-induced apoptosis. Pretreatment of cancer cells with pan caspase inhibitor, z-VAD inhibited activities of both initiator caspases (e.g., caspase-8 and -9) and executioner caspase-3. Neem induced the release of cytochrome c and apoptosis-inducing factor (AIF) from mitochondria, suggesting the involvement of both caspase-dependent and AIF-mediated apoptosis. p21 deficiency caused an increase in caspase activities at lower doses of neem, whereas p53 deficiency did not modulate neem-induced caspase activation. Additionally, neem treatment resulted in the accumulation of LC3-II in cancer cells, suggesting the involvement of autophagy in neem-induced cancer cell death. Low doses of autophagy inhibitors (i.e., 3-methyladenine and LY294002) did not prevent accumulation of neem-induced LC3-II in cancer cells. Silencing of ATG5 or Beclin-1 further enhanced neem-induced cell death. Phosphoinositide 3-kinase (PI3K) or autophagy inhibitors increased neem-induced caspase-3 activation and inhibition of caspases enhanced neem-induced autophagy. Together, for the first time, we demonstrate that neem induces caspase-dependent and AIF-mediated apoptosis, and autophagy in cancer cells.

Long-term consequences of chronic fluoxetine exposure on the expression of myelination-related genes in the rat hippocampus

PubMed Central

Kroeze, Y; Peeters, D; Boulle, F; van den Hove, D L A; van Bokhoven, H; Zhou, H; Homberg, J R

2015-01-01

The selective serotonin reuptake inhibitor (SSRI) fluoxetine is widely prescribed for the treatment of symptoms related to a variety of psychiatric disorders. After chronic SSRI treatment, some symptoms remediate on the long term, but the underlying mechanisms are not yet well understood. Here we studied the long-term consequences (40 days after treatment) of chronic fluoxetine exposure on genome-wide gene expression. During the treatment period, we measured body weight; and 1 week after treatment, cessation behavior in an SSRI-sensitive anxiety test was assessed. Gene expression was assessed in hippocampal tissue of adult rats using transcriptome analysis and several differentially expressed genes were validated in independent samples. Gene ontology analysis showed that upregulated genes induced by chronic fluoxetine exposure were significantly enriched for genes involved in myelination. We also investigated the expression of myelination-related genes in adult rats exposed to fluoxetine at early life and found two myelination-related genes (Transferrin (Tf) and Ciliary neurotrophic factor (Cntf)) that were downregulated by chronic fluoxetine exposure. Cntf, a neurotrophic factor involved in myelination, showed regulation in opposite direction in the adult versus neonatally fluoxetine-exposed groups. Expression of myelination-related genes correlated negatively with anxiety-like behavior in both adult and neonatally fluoxetine-exposed rats. In conclusion, our data reveal that chronic fluoxetine exposure causes on the long-term changes in expression of genes involved in myelination, a process that shapes brain connectivity and contributes to symptoms of psychiatric disorders. PMID:26393488

Cytosolic NADP(+)-dependent isocitrate dehydrogenase regulates cadmium-induced apoptosis.

PubMed

Shin, Seoung Woo; Kil, In Sup; Park, Jeen-Woo

2010-04-01

Cadmium ions have a high affinity for thiol groups. Therefore, they may disturb many cellular functions. We recently reported that cytosolic NADP(+)-dependent isocitrate dehydrogenase (IDPc) functions as an antioxidant enzyme to supply NADPH, a major source of reducing equivalents to the cytosol. Cadmium decreased the activity of IDPc both as a purified enzyme and in cultured cells. In the present study, we demonstrate that the knockdown of IDPc expression in HEK293 cells greatly enhances apoptosis induced by cadmium. Transfection of HEK293 cells with an IDPc small interfering RNA significantly decreased the activity of IDPc and enhanced cellular susceptibility to cadmium-induced apoptosis as indicated by the morphological evidence of apoptosis, DNA fragmentation and condensation, cellular redox status, mitochondria redox status and function, and the modulation of apoptotic marker proteins. Taken together, our results suggest that suppressing the expression of IDPc enhances cadmium-induced apoptosis of HEK293 cells by increasing disruption of the cellular redox status. Copyright 2009 Elsevier Inc. All rights reserved.

Interdependence of Bad and Puma during ionizing-radiation-induced apoptosis.

PubMed

Toruno, Cristhian; Carbonneau, Seth; Stewart, Rodney A; Jette, Cicely

2014-01-01

Ionizing radiation (IR)-induced DNA double-strand breaks trigger an extensive cellular signaling response that involves the coordination of hundreds of proteins to regulate DNA repair, cell cycle arrest and apoptotic pathways. The cellular outcome often depends on the level of DNA damage as well as the particular cell type. Proliferating zebrafish embryonic neurons are highly sensitive to IR-induced apoptosis, and both p53 and its transcriptional target puma are essential mediators of the response. The BH3-only protein Puma has previously been reported to activate mitochondrial apoptosis through direct interaction with the pro-apoptotic Bcl-2 family proteins Bax and Bak, thus constituting the role of an "activator" BH3-only protein. This distinguishes it from BH3-only proteins like Bad that are thought to indirectly promote apoptosis through binding to anti-apoptotic Bcl-2 family members, thereby preventing the sequestration of activator BH3-only proteins and allowing them to directly interact with and activate Bax and Bak. We have shown previously that overexpression of the BH3-only protein Bad in zebrafish embryos supports normal embryonic development but greatly sensitizes developing neurons to IR-induced apoptosis. While Bad has previously been shown to play only a minor role in promoting IR-induced apoptosis of T cells in mice, we demonstrate that Bad is essential for robust IR-induced apoptosis in zebrafish embryonic neural tissue. Moreover, we found that both p53 and Puma are required for Bad-mediated radiosensitization in vivo. Our findings show the existence of a hierarchical interdependence between Bad and Puma whereby Bad functions as an essential sensitizer and Puma as an essential activator of IR-induced mitochondrial apoptosis specifically in embryonic neural tissue.

The role of cPLA2 in Methylglyoxal-induced cell apoptosis of HUVECs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yuan, Jie; Zhu, Chao; Hong, Yali

2017-05-15

Methylglyoxal (MGO), a highly reactive dicarbonyl compound, is mainly formed as a byproduct of glycolysis. Elevated MGO level is known to induce apoptosis of vascular endothelial cells, which is implicated with progression of atherosclerosis and diabetic complications. However, the underlying mechanisms have not been exhaustively investigated yet. Here, we further characterized the mechanisms how MGO induced apoptosis in human umbilical vein endothelial cells (HUVECs). Our data revealed that cytosolic phospholipase A2 (cPLA2) played an important role in MGO-induced cell apoptosis. It was found that MGO could increase both the activity and expression of cPLA2. Inhibition of cPLA2 by Pyrrophenone (PYR)more » or siRNA significantly attenuated the MGO-induced apoptosis. Additionally, MGO time-dependently decreased the phosphorylation of nuclear factor κB (NF-κB). Pretreatment of the cells with NF-κB inhibitor, BAY11-7082, further increased MGO-induced apoptosis of HUVECs, indicating that NF-κB played a survival role in this MGO-induced apoptosis. Furthermore, in the presence of si-cPLA2 or PYR, MGO no longer decreased NF-κB phosphorylation. Beyond that, the antioxidant N-acetyl cysteine (NAC) could reverse the changes of both cPLA2 and NF-κB caused by MGO. p38, the upstream of cPLA2, was also significantly phosphorylated by MGO. However, p38 inhibitor failed to reverse the apoptosis induced by MGO. This study gives an important insight into the downstream signaling mechanisms of MGO, cPLA2-NF-κB, in endothelial apoptosis. - Highlights: • cPLA2 participated in MGO-induced HUVECs apoptosis. • Inhibition of NF-κB was involved in MGO-cPLA2-mediated cell apoptosis. • Antioxidant NAC attenuated MGO-induced cPLA2 activation and cell apoptosis.« less

[Progress on mechanism of cell apoptosis induced by rubella virus].

PubMed

Li, Zhen-mei; Chu, Fu-lu; Liu, Ying; Wang, Zhi-yu

2013-09-01

Rubella virus (RV), a member of the family Togaviridae, can induce apoptosis of host cells in vitro. Protein kinases of the Ras-Raf-MEK-ERK pathway and PI3K-Akt pathway play essential roles in virus multiplication, cell survival and apoptosis. Proteins p53 and TAp63 that bind to specific DNA sequences stimulate Bax in a manner to produce functional pores that facilitate release of mitochondrial cytochrome c and downstream caspase activation. In this review, the molecular mechanisms of RV-induced cell apoptosis, including RV-infected cell lines, pathological changes in cell components and apoptosis signaling pathways are summarized.

Effects of Fluoxetine on Hippocampal Neurogenesis and Neuroprotection in the Model of Global Cerebral Ischemia in Rats

PubMed Central

Kisel, Alena; Kudabaeva, Marina; Chernysheva, Galina; Smolyakova, Vera; Krutenkova, Elena; Wasserlauf, Irina; Plotnikov, Mark; Yarnykh, Vasily

2018-01-01

A selective serotonin reuptake inhibitor, fluoxetine, has recently attracted a significant interest as a neuroprotective therapeutic agent. There is substantial evidence of improved neurogenesis under fluoxetine treatment of brain ischemia in animal stroke models. We studied long-term effects of fluoxetine treatment on hippocampal neurogenesis, neuronal loss, inflammation, and functional recovery in a new model of global cerebral ischemia (GCI). Brain ischemia was induced in adult Wistar male rats by transient occlusion of three main vessels originating from the aortic arch and providing brain blood supply. Fluoxetine was injected intraperitoneally in a dose of 20 mg/kg for 10 days after surgery. To evaluate hippocampal neurogenesis at time points 10 and 30 days, 5-Bromo-2′-deoxyuridine was injected at days 8–10 after GCI. According to our results, 10-day fluoxetine injections decreased neuronal loss and inflammation, improved survival and functional recovery of animals, enhanced neurogenesis, and prevented an early pathological increase in neural stem cell recruitment in the subgranular zone (SGZ) of the hippocampus without reducing the number of mature neurons at day 30 after GCI. In summary, this study suggests that fluoxetine may provide a promising therapy in cerebral ischemia due to its neuroprotective, anti-inflammatory, and neurorestorative effect. PMID:29304004

Apoptosis of lactotrophs induced by D2 receptor activation is estrogen dependent.

PubMed

Radl, Daniela B; Zárate, Sandra; Jaita, Gabriela; Ferraris, Jimena; Zaldivar, Verónica; Eijo, Guadalupe; Seilicovich, Adriana; Pisera, Daniel

2008-01-01

Dopamine (DA) inhibits prolactin release and reduces lactotroph proliferation by activating D2 receptors. DA and its metabolite, 6-hydroxydopamine (6-OHDA), induce apoptosis in different cell types. DA receptors and DA transporter (DAT) were implicated in this action. Considering that estradiol sensitizes anterior pituitary cells to proapoptotic stimuli, we investigated the effect of estradiol on the apoptotic action of DA and 6-OHDA in anterior pituitary cells, and the involvement of the D2 receptor and DAT in the proapoptotic effect of DA. Viability of cultured anterior pituitary cells from ovariectomized rats was determined by MTS assay. Apoptosis was evaluated by Annexin-V/flow cytometry and TUNEL. Lactotrophs were identified by immunocytochemistry. DA induced apoptosis of lactotrophs in an estrogen-dependent manner. In contrast, estradiol was not required to trigger the apoptotic action of 6-OHDA. Cabergoline, a D2 receptor agonist, induced lactotroph apoptosis, while sulpiride, a D2 receptor antagonist, blocked DA-induced cell death. The blockade of DAT by GBR12909 did not affect the apoptotic action of DA, but inhibited 6-OHDA-induced apoptosis. These data show that DA, through D2 receptor activation, induces apoptosis of estrogen-sensitized anterior pituitary cells, and suggest that DA contributes to the control of lactotroph number not only by inhibiting proliferation but also by inducing apoptosis. 2008 S. Karger AG, Basel.

Mitochondria-derived reactive oxygen species drive GANT61-induced mesothelioma cell apoptosis.

PubMed

Lim, Chuan Bian; Prêle, Cecilia M; Baltic, Svetlana; Arthur, Peter G; Creaney, Jenette; Watkins, D Neil; Thompson, Philip J; Mutsaers, Steven E

2015-01-30

Gli transcription factors of the Hedgehog (Hh) pathway have been reported to be drivers of malignant mesothelioma (MMe) cell survival. The Gli inhibitor GANT61 induces apoptosis in various cancer cell models, and has been associated directly with Gli inhibition. However various chemotherapeutics can induce cell death through generation of reactive oxygen species (ROS) but whether ROS mediates GANT61-induced apoptosis is unknown. In this study human MMe cells were treated with GANT61 and the mechanisms regulating cell death investigated. Exposure of MMe cells to GANT61 led to G1 phase arrest and apoptosis, which involved ROS but not its purported targets, GLI1 or GLI2. GANT61 triggered ROS generation and quenching of ROS protected MMe cells from GANT61-induced apoptosis. Furthermore, we demonstrated that mitochondria are important in mediating GANT61 effects: (1) ROS production and apoptosis were blocked by mitochondrial inhibitor rotenone; (2) GANT61 promoted superoxide formation in mitochondria; and (3) mitochondrial DNA-deficient LO68 cells failed to induce superoxide, and were more resistant to apoptosis induced by GANT61 than wild-type cells. Our data demonstrate for the first time that GANT61 induces apoptosis by promoting mitochondrial superoxide generation independent of Gli inhibition, and highlights the therapeutic potential of mitochondrial ROS-mediated anticancer drugs in MMe.

Autophagy regulates chlorpyrifos-induced apoptosis in SH-SY5Y cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, Jae Hyeon; Hanyang Biomedical Research Institute, Seoul; Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul

Recent studies have shown that up-regulation of autophagy may be a tractable therapeutic intervention for clearing disease-causing proteins, including α-synuclein, ubiquitin, and other misfolded or aggregated proteins in pesticide-induced neurodegeneration. In a previous study, we reported that chlorpyrifos (CPF)-induced mitochondria-dependent apoptosis is mediated through reactive oxygen species in SH-SY5Y cells. In this study, we explored a novel pharmacotherapeutic approach to prevent CPF neurotoxicity involving the regulation of autophagy. We investigated the modulation of CPF-induced apoptosis according to autophagy regulation. We found that CPF induced apoptosis in SH-SY5Y cells, as demonstrated by the activation of caspase-3 and nuclear condensation. In addition,more » we observed that cells treated with CPF underwent autophagic cell death by monitoring the expression of LC3-II and p62. Pretreatment with the autophagy inducer rapamycin significantly enhanced the cell viability of CPF-exposed cells, and the enhancement of cell viability was partially due to alleviation of CPF-induced apoptosis via a decrease in levels of cleaved caspase-3. Specifically, rapamycin pretreatment decreased Bax and increased Bcl-2 expression in mitochondria. In addition, rapamycin significantly decreased cytochrome c release in from mitochondria into the cytosol. However, pretreatment of cells with the autophagy inhibitor, 3-methyladenine (3MA), remarkably increased CPF toxicity in these cells; this with correlated with increased expression of Bax and decreased expression of Bcl-2 in mitochondria. Our results suggest that CPF-induced cytotoxicity is modified by autophagy regulation and that rapamycin protects against CPF-induced apoptosis by enhancing autophagy. Pharmacologic induction of autophagy by rapamycin may be a useful treatment strategy in neurodegenerative disorders. - Highlights: ► Chlorpyrifos (CPF) is cytotoxic to SH-SY5Y cells ► CPF-induced cytotoxicity is

Mitochondrial dysfunction in choline deficiency-induced apoptosis in cultured rat hepatocytes.

PubMed

Guo, Wei-Xing; Pye, Quentin N; Williamson, Kelly S; Stewart, Charles A; Hensley, Kenneth L; Kotake, Yashige; Floyd, Robert A; Broyles, Robert H

2005-09-01

Our recent studies have demonstrated that generation of ROS is associated with choline deficiency (CD)-induced apoptosis in CWSV-1 cells, an immortalized rat hepatocyte that becomes tumorigenic by stepwise culturing in decreasing levels of choline. In the present study, we investigated the effect of CD on loss of mitochondrial membrane potential (MMP), using the JC-1 probe by FASCAN assay. Our data demonstrate that MMP in CD-cultured cells was decreased in a time- and dose-dependent manner and that significant disruption occurred at 24 h, relative to high choline (HC, 70 microM) cultured cells. In order to investigate further the relationship among the CD-induced ROS, MMP collapse, and apoptosis, we examined the effects of different inhibitors on ROS production, MMP disruption, and apoptosis in CD or HC-cultured CWSV-1 cells. These data indicate that the disruption of MMP is an upstream event in CD-induced apoptosis, and mitochondrial dysfunction plays a key role in mediating CD-induced apoptosis in CWSV-1 cells.

Effect of Fluoxetine on the Hippocampus of Wistar Albino Rats in Cold Restraint Stress Model

PubMed Central

Raghunath, Gunapriya; Ilango, Saraswathi; Vijayakumar, J; Vijayaraghavan, R

2017-01-01

Introduction Stress has been known to be a potential modulator of learning and memory. Long term stress can lead to depression. Fluoxetine is a selective serotonin reuptake inhibitor group of drug used in the treatment of depression. Aim The present study was conducted to evaluate the potential of Fluoxetine on cold restraint induced stress in the hippocampus of Wistar rats. Materials and Methods A total of 18 male wistar albino rats were divided randomly into three groups (n=6). Group 1 was the control group which were kept in normal laboratory conditions. Group 2 was the negative control group which were given cold restraint stress for period of four weeks. Group 3 was the experimental group, where the animals were pretreated with fluoxetine 10 mg/kg for a period of one week followed by cold restraint stress for 30 minutes and cotreated with fluoxetine 10 mg/kg for a period of four weeks. The whole study was done for a period of five weeks followed by behavioural studies and subsequently sacrificed with removal of brain for various histological, Immunohistochemical (IHC), neurochemical and antioxidant analysis. The values were expressed as Mean±SEM. One-way analysis of variance followed by Tukey’s multiple comparisons test was used for the comparison of means. A probability of 0.05 and less was taken as statistically significant using Prism Graphpad software version 6.01. Results The results show there was significant improvement in the Morris water maze test after treatment with fluoxetine in Group 2. Similar results were also noted in the levels of neurotransmitters and antioxidant levels in brain and also in the number of cells counted in IHC and histological studies by H&E when Group 3 was compared with Group 2. The treatment reversed the damage in Group 2 which was comparable with the control group. Conclusion The results revealed that administration of fluoxetine 10 mg/kg given orally has a potential antistressor effect by improving the neurogenic and

Effect of Fluoxetine on the Hippocampus of Wistar Albino Rats in Cold Restraint Stress Model.

PubMed

Jayakumar, Saikarthik; Raghunath, Gunapriya; Ilango, Saraswathi; Vijayakumar, J; Vijayaraghavan, R

2017-06-01

Stress has been known to be a potential modulator of learning and memory. Long term stress can lead to depression. Fluoxetine is a selective serotonin reuptake inhibitor group of drug used in the treatment of depression. The present study was conducted to evaluate the potential of Fluoxetine on cold restraint induced stress in the hippocampus of Wistar rats. A total of 18 male wistar albino rats were divided randomly into three groups (n=6). Group 1 was the control group which were kept in normal laboratory conditions. Group 2 was the negative control group which were given cold restraint stress for period of four weeks. Group 3 was the experimental group, where the animals were pretreated with fluoxetine 10 mg/kg for a period of one week followed by cold restraint stress for 30 minutes and cotreated with fluoxetine 10 mg/kg for a period of four weeks. The whole study was done for a period of five weeks followed by behavioural studies and subsequently sacrificed with removal of brain for various histological, Immunohistochemical (IHC), neurochemical and antioxidant analysis. The values were expressed as Mean±SEM. One-way analysis of variance followed by Tukey's multiple comparisons test was used for the comparison of means. A probability of 0.05 and less was taken as statistically significant using Prism Graphpad software version 6.01. The results show there was significant improvement in the Morris water maze test after treatment with fluoxetine in Group 2. Similar results were also noted in the levels of neurotransmitters and antioxidant levels in brain and also in the number of cells counted in IHC and histological studies by H&E when Group 3 was compared with Group 2. The treatment reversed the damage in Group 2 which was comparable with the control group. The results revealed that administration of fluoxetine 10 mg/kg given orally has a potential antistressor effect by improving the neurogenic and neuroprotective effect on the cold restraint stress induced

Peroxisome proliferators induce apoptosis in hepatoma cells.

PubMed

Canuto, R A; Muzio, G; Bonelli, G; Maggiora, M; Autelli, R; Barbiero, G; Costelli, P; Brossa, O; Baccino, F M

1998-01-01

In the AH-130 hepatoma, a poorly differentiated tumor, maintained by weekly transplantations in rats, a low percentage of cells spontaneously underwent apoptosis, mainly during the transition from logarithmic- to stationary-growth phase. It was possible to induce massive apoptosis of cells by treating them with clofibrate, a peroxisome proliferator and hypolipidemic drug. Similar results were obtained with HepG2 cells. With 1 mM clofibrate, apoptosis began to manifest itself after 1 h of treatment in vitro, and was assessed by morphological analysis, by DNA fragmentation carried out with agarose gel electrophoresis, and with flow cytometric determination of terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling. The mechanisms whereby clofibrate induces apoptosis are still unclear. Since the peroxisome proliferator-activated receptor was expressed at a very low level and was not stimulated by clofibrate in the AH-130 hepatoma cells, its involvement seems unlikely. Moreover, lipid peroxidation was not increased after clofibrate treatment. Phospholipids and cholesterol were significantly decreased. The decreased cholesterol content might suggest an inhibition of the mevalonate pathway and, therefore, of isoprenylation of proteins involved in cell proliferation.

Modulation of iridovirus-induced apoptosis by endocytosis, early expression, JNK, and apical caspase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chitnis, Nilesh S.; D'Costa, Susan M.; Paul, Eric R.

Chilo iridescent virus (CIV) is the type species for the family Iridoviridae, which are large, isometric, cytoplasmic dsDNA viruses. We examined the mechanism of apoptosis induction by CIV. High CIV doses (CIV{sub XS}; 400 {mu}g/ml), UV-irradiated virus (CIV{sub UV}; 10 {mu}g/ml) and CVPE (CIV protein extract; 10 {mu}g/ml) induced apoptosis in 60% of treated Choristoneura fumiferana (IPRI-CF-124T) cells. Normal doses of infectious CIV (10 {mu}g/ml) induced apoptosis in only 10% of C. fumiferana (CF) cells. Apoptosis was inhibited by Z-IETD-FMK, an apical caspase inhibitor, indicating that CIV-induced apoptosis requires caspase activity. The putative caspase in CF cells was designated Cf-caspase-i.more » CIV{sub UV} or CVPE enhanced Cf-caspase-i activity by 80% at 24 h relative to mock-treated cells. Since the MAP kinase pathway induces or inhibits apoptosis depending on the context, we used JNK inhibitor SP600125 and demonstrated drastic suppression of CVPE-induced apoptosis. Thus, the JNK signaling pathway is significant for apoptosis in this system. Virus interaction with the cell surface was not sufficient for apoptosis since CIV{sub UV} particles bound to polysterene beads failed to induce apoptosis. Endocytosis inhibitors (bafilomycin or ammonium chloride) negated apoptosis induction by CIV{sub UV}, CIV{sub XS} or CVPE indicating that entry through this mode is required. Given the weak apoptotic response to infectious CIV, we postulated that viral gene expression inhibited apoptosis. CIV infection of cells pretreated with cycloheximide induced apoptosis in 69% of the cells compared to 10% in normal infections. Furthermore, blocking viral DNA replication with aphidicolin or phosphonoacetic acid suppressed apoptosis and Cf-caspase-i activity, indicating that early viral expression is necessary for inhibition of apoptosis, and de novo synthesis of viral proteins is not required for induction. We show for the first time that, in a member of the family

Differential Peripheral Proteomic Biosignature of Fluoxetine Response in a Mouse Model of Anxiety/Depression

PubMed Central

Mendez-David, Indira; Boursier, Céline; Domergue, Valérie; Colle, Romain; Falissard, Bruno; Corruble, Emmanuelle; Gardier, Alain M.; Guilloux, Jean-Philippe; David, Denis J.

2017-01-01

The incorporation of peripheral biomarkers in the treatment of major depressive disorders (MDD) could improve the efficiency of treatments and increase remission rate. Peripheral blood mononuclear cells (PBMCs) represent an attractive biological substrate allowing the identification of a drug response signature. Using a proteomic approach with high-resolution mass spectrometry, the present study aimed to identify a biosignature of antidepressant response (fluoxetine, a Selective Serotonin Reuptake Inhibitor) in PBMCs in a mouse model of anxiety/depression. Following determination of an emotionality score, using complementary behavioral analysis of anxiety/depression across three different tests (Elevated Plus Maze, Novelty Suppressed Feeding, Splash Test), we showed that a 4-week corticosterone treatment (35 μg/ml, CORT model) in C57BL/6NTac male mice induced an anxiety/depressive-like behavior. Then, chronic fluoxetine treatment (18 mg/kg/day for 28 days in the drinking water) reduced corticosterone-induced increase in emotional behavior. However, among 46 fluoxetine-treated mice, only 30 of them presented a 50% decrease in emotionality score, defining fluoxetine responders (CORT/Flx-R). To determine a peripheral biological signature of fluoxetine response, proteomic analysis was performed from PBMCs isolated from the “most” affected corticosterone/vehicle (CORT/V), corticosterone/fluoxetine responders and non-responders (CORT/Flx-NR) animals. In comparison to CORT/V, a total of 263 proteins were differently expressed after fluoxetine exposure. Expression profile of these proteins showed a strong similarity between CORT/Flx-R and CORT/Flx-NR (R = 0.827, p < 1e-7). Direct comparison of CORT/Flx-R and CORT/Flx-NR groups revealed 100 differently expressed proteins, representing a combination of markers associated either with the maintenance of animals in a refractory state, or associated with behavioral improvement. Finally, 19 proteins showed a differential

Radioiodide induces apoptosis in human thyroid tissue in culture.

PubMed

Russo, Eleonora; Guerra, Anna; Marotta, Vincenzo; Faggiano, Antongiulio; Colao, Annamaria; Del Vecchio, Silvana; Tonacchera, Massimo; Vitale, Mario

2013-12-01

Radioiodide ((131)I) is routinely used for the treatment of toxic adenoma, Graves' disease, and for ablation of thyroid remnant after thyroidectomy in patients with thyroid cancer. The toxic effects of ionizing radiations on living cells can be mediated by a necrotic and/or apoptotic process. The involvement of apoptosis in radiation-induced cell death in the thyrocytes has been questioned. The knowledge of the mechanisms that underlie the thyrocyte death in response to radiations can help to achieve a successful treatment with the lowest (131)I dose. We developed a method to study the effects of (131)I in human thyroid tissue in culture, by which we demonstrated that (131)I induces thyroid cell apoptosis. Human thyroid tissues of about 1 mm(3) were cultured in vitro and cell viability was determined up to 3 weeks by the MTT assay. Radioiodide added to the culture medium was actively taken up by the tissues. The occurrence of apoptosis in the thyrocytes was assessed by measuring the production of a caspase-cleavage fragment of cytokeratin 18 (M30) by an enzyme-linked immunoassay. Neither variation of cell number nor spontaneous apoptosis was revealed after 1 week of culture. (131)I added to the culture medium induced a dose-dependent and a time-dependent generation of M30 fragment. The apoptotic process was confirmed by the generation of caspase-3 and PARP cleavage products. These results demonstrate that (131)I induces apoptosis in human thyrocytes. Human thyroid tissue cultures may be useful to investigate the cell death pathways induced by (131)I.

Caspase-12 is involved in stretch-induced apoptosis mediated endoplasmic reticulum stress.

PubMed

Zhang, Qiang; Liu, Jianing; Chen, Shulan; Liu, Jing; Liu, Lijuan; Liu, Guirong; Wang, Fang; Jiang, Wenxin; Zhang, Caixia; Wang, Shuangyu; Yuan, Xiao

2016-04-01

It is well recognized that mandibular growth, which is caused by a variety of functional appliances, is considered to be the result of both neuromuscular and skeletal adaptations. Accumulating evidence has demonstrated that apoptosis plays an important role in the adaptation of skeletal muscle function. However, the underlying mechanism of apoptosis that is induced by stretch continues to be incompletely understood. Endoplasmic reticulum stress (ERS), a newly defined signaling pathway, initiates apoptosis. This study seeks to determine if caspase-12 is involved in stretch-induced apoptosis mediated endoplasmic reticulum stress in myoblast and its underlying mechanism. Apoptosis was assessed by Hochest staining, DAPI staining and annexin V binding and PI staining. ER chaperones, such as GRP78, CHOP and caspase-12, were determined by reverse transcription polymerase chain reaction (RT-PCR) and Western blot. Furthermore, caspase-12 inhibitor was used to value the mechanism of the caspase-12 pathway. Apoptosis of myoblast, which is subjected to cyclic stretch, was observed in a time-dependent manner. We found that GRP78 mRNA and protein were significantly increased and CHOP and caspase-12 were activated in myoblast that was exposed to cyclic stretch. Caspase-12 inhibition reduced stretch-induced apoptosis, and caspase-12 activated caspase-3 to induce apoptosis. We concluded that caspase-12 played an important role in stretch-induced apoptosis that is associated by endoplasmic reticulum stress by activating caspase-3.

Parvovirus B19-Induced Apoptosis of Hepatocytes

PubMed Central

Poole, Brian D.; Karetnyi, Yuory V.; Naides, Stanley J.

2004-01-01

Parvovirus B19 (B19 virus) can persist in multiple tissues and has been implicated in a variety of diseases, including acute fulminant liver failure. The mechanism by which B19 virus induces liver failure remains unknown. Hepatocytes are nonpermissive for B19 virus replication. We previously reported that acute fulminant liver failure associated with B19 virus infection was characterized by hepatocellular dropout. We inoculated both primary hepatocytes and the hepatocellular carcinoma cell line Hep G2 with B19 virus and assayed for apoptosis by using annexin V staining. Reverse transcriptase PCR analysis and immunofluorescence demonstrated that B19 virus was able to infect the cells and produce its nonstructural protein but little or no structural capsid protein. Infection with B19 virus induced means of 28% of Hep G2 cells and 10% of primary hepatocytes to undergo apoptosis, which were four- and threefold increases, respectively, over background levels. Analysis of caspase involvement showed that B19 virus-inoculated cultures had a significant increase in the number of cells with active caspase 3. Inhibition studies demonstrated that caspases 3 and 9, but not caspase 8, are required for B19 virus-induced apoptosis. PMID:15220451

Dihydroartemisinin induces apoptosis preferentially via a Bim-mediated intrinsic pathway in hepatocarcinoma cells.

PubMed

Qin, Guiqi; Zhao, ChuBiao; Zhang, Lili; Liu, Hongyu; Quan, Yingyao; Chai, Liuying; Wu, Shengnan; Wang, Xiaoping; Chen, Tongsheng

2015-08-01

This report is designed to dissect the detail molecular mechanism by which dihydroartemisinin (DHA), a derivative of artemisinin, induces apoptosis in human hepatocellular carcinoma (HCC) cells. DHA induced a loss of the mitochondrial transmemberane potential (ΔΨm), release of cytochrome c, activation of caspases, and externalization of phosphatidylserine indicative of apoptosis induction. Compared with the modest inhibitory effects of silencing Bax, silencing Bak largely prevented DHA-induced ΔΨm collapse and apoptosis though DHA induced a commensurable activation of Bax and Bak, demonstrating a key role of the Bak-mediated intrinsic apoptosis pathway. DHA did not induce Bid cleavage and translocation from cytoplasm to mitochondria and had little effects on the expressions of Puma and Noxa, but did increase Bim and Bak expressions and decrease Mcl-1 expression. Furthermore, the cytotoxicity of DHA was remarkably reduced by silencing Bim, and modestly but significantly reduced by silencing Puma or Noxa. Silencing Bim or Noxa preferentially reduced DHA-induced Bak activation, while silencing Puma preferentially reduced DHA-induced Bax activation, demonstrating that Bim and to a lesser extent Noxa act as upstream mediators to trigger the Bak-mediated intrinsic apoptosis pathway. In addition, silencing Mcl-1 enhanced DHA-induced Bak activation and apoptosis. Taken together, our data demonstrate a crucial role of Bim in preferentially regulating the Bak/Mcl-1 rheostat to mediate DHA-induced apoptosis in HCC cells.

Fluoxetine. A pharmacoeconomic review of its use in depression.

PubMed

Wilde, M I; Benfield, P

1998-05-01

Depressive illness is a common, often unrecognised and untreated condition with substantial associated costs, particularly indirect costs (e.g. lost productivity and absenteeism). The improved tolerability profile of fluoxetine and associated lower discontinuation rates, the relative safety of the drug in overdosage and its similar efficacy compared with tricyclic antidepressants have provided the main rationale for using this agent in depressed patients. Pharmacoeconomic analyses of fluoxetine have mainly sought to determine whether its higher acquisition cost in comparison with tricyclic antidepressants can be offset by reductions in other costs and whether the use of this agent as first-line therapy can be justified. Studies have also attempted to determine whether the selective serotonin reuptake inhibitors (SSRIs) can be distinguished from one another on pharmacoeconomic grounds; overall efficacy and tolerability of these agents appear to be similar, although tolerability data are conflicting. Most analyses have been of a retrospective database or clinical decision analytic model design; two prospective trials (one conducted in a naturalistic setting) have been conducted. These studies have mainly considered direct treatment costs only from the perspective of the healthcare payer. Available evidence suggests that overall total direct healthcare costs for patients who start antidepressant therapy with fluoxetine are similar to, or lower than, those for patients who start therapy with tricyclic agents or other SSRIs. Offsetting of the higher acquisition cost of fluoxetine compared with that of tricyclic agents may be accounted for by lower in- and outpatient costs with fluoxetine, a possible lower risk of absenteeism from work and lower mean total medical costs associated with acute overdosage. Between-treatment differences in drug use patterns may also, in part, explain the observed differences in total healthcare costs between fluoxetine and other

Chronic fluoxetine inhibits sexual behavior in the male rat: reversal with oxytocin.

PubMed

Cantor, J M; Binik, Y M; Pfaus, J G

1999-06-01

Selective serotonin reuptake inhibitors, used widely in the treatment of depression, progressively inhibit sexual orgasm in many patients and induce a transient inhibition of sexual desire. We attempted to model the effects of these drugs in sexually experienced male rats during tests of copulation in bilevel chambers. These chambers allow the study of both appetitive and consummatory sexual responses of male rats. Males were treated daily with fluoxetine hydrochloride (0, 1, 5, or 10 mg/kg) and tested for sexual behavior with receptive females at 4-day intervals. Rats were treated with oxytocin (200 ng/kg) or saline after ejaculations had decreased. Fluoxetine decreased ejaculatory responses of male rats in a dose- and time-dependent fashion, but left the copulatory efficiency of the males intact. In contrast, conditioned level changing, a measure of appetitive sexual excitement, was inhibited following acute and chronic treatment with 10 mg/kg, although tolerance may have developed to the effect of 5 mg/kg. Subsequent administration of oxytocin restored the ejaculatory response but not the measure of sexual excitement to baseline levels. The reversal by oxytocin of the fluoxetine-induced deficit in ejaculations is consistent with the hypothesis that serotonin suppresses ejaculatory mechanisms by interrupting the action of oxytocin, which normally accompanies sexual behavior. Co-administration of oxytocin may help to alleviate the predominant sexual side effect of serotonin reuptake blockers.

Osteoblasts Protect AML Cells from SDF-1-Induced Apoptosis

PubMed Central

Kremer, Kimberly N.; Dudakovic, Amel; McGee-Lawrence, Meghan E.; Philips, Rachael L.; Hess, Allan D.; Smith, B. Douglas; van Wijnen, Andre J.; Karp, Judith E.; Kaufmann, Scott H.; Westendorf, Jennifer J.; Hedin, Karen E.

2014-01-01

The bone marrow provides a protective environment for acute myeloid leukemia (AML) cells that often allows leukemic stem cells to survive standard chemotherapeutic regimens. Targeting these leukemic stem cells within the bone marrow is critical for preventing relapse. We recently demonstrated that SDF-1, a chemokine abundant in the bone marrow, induces apoptosis in AML cell lines and in patient samples expressing high levels of its receptor, CXCR4. Here we show that a subset of osteoblast lineage cells within the bone marrow can protect AML cells from undergoing apoptosis in response to the SDF-1 naturally present in that location. In co-culture systems, osteoblasts at various stages of differentiation protected AML cell lines and patient isolates from SDF-1-induced apoptosis. The differentiation of the osteoblast cell lines, MC3T3 and W-20-17, mediated this protection via a cell contact-independent mechanism. In contrast, bone marrow-derived mesenchymal cells, the precursors of osteoblasts, induced apoptosis in AML cells via a CXCR4-dependent mechanism and failed to protect AML cells from exogenously added SDF-1. These results indicate that osteoblasts in the process of differentiation potently inhibit the SDF-1-driven apoptotic pathway of CXCR4-expressing AML cells residing in the bone marrow. Drugs targeting this protective mechanism could potentially provide a new approach to treating AML by enhancing the SDF-1-induced apoptosis of AML cells residing within the bone marrow microenvironment. PMID:24851270

GGPPS deficiency aggravates CCl4-induced liver injury by inducing hepatocyte apoptosis.

PubMed

Chen, Wei-Bo; Lai, Shan-Shan; Yu, De-Cai; Liu, Jia; Jiang, Shan; Zhao, Dan-Dan; Ding, Yi-Tao; Li, Chao-Jun; Xue, Bin

2015-04-28

GGPPS catalyses the expression of GGPP, a key protein in the mevalonate metabolic pathway. HMG-CoA reductase inhibitor statins can induce liver injury by inhibiting GGPP. However, the function of GGPPS in liver injury has not yet been revealed. In this study, we found that GGPPS increased in liver injury and that GGPPS deletion augmented liver injury and fibrosis. GGPPS inhibition induced hepatocyte apoptosis, inflammation and TGF-β1 secretion, which activated hepatic stellate cells. Our findings imply that GGPPS deletion induces hepatocyte apoptosis, which makes the liver vulnerable to hepatotoxicity. Copyright © 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Cigarette Smoke–Induced CXCR3 Receptor Up-Regulation Mediates Endothelial Apoptosis

PubMed Central

Green, Linden A.; Petrusca, Daniela; Rajashekhar, Gangaraju; Gianaris, Tom; Schweitzer, Kelly S.; Wang, Liang; Justice, Matthew J.; Petrache, Irina

2012-01-01

Endothelial monocyte–activating polypeptide II (EMAP II) and interferon-inducible protein (IP)–10 are proinflammatory mediators, which in addition to their chemokine activities, selectively induce apoptosis in endothelial cells and are up-regulated in the lungs of cigarette smoke–exposed humans. Previously, we showed that EMAP II is an essential mediator of cigarette smoke–induced lung emphysema in mice linking endothelial cell apoptosis with inflammation. Here we addressed the role of the CXCR3 receptor in EMAP II–induced and IP-10–induced apoptosis in endothelial cells and its regulation by cigarette smoke. We found that both neutralizing antibodies and small inhibitory RNA to CXCR3 abrogated EMAP II–induced and IP-10–induced endothelial caspase-3 activation and DNA fragmentation. CXCR3 receptor surface expression in human lung microvascular endothelial cells and in lung tissue endothelium was up-regulated by exposure to cigarette smoke. In tissue culture conditions, EMAP II–induced and IP-10–induced apoptosis was enhanced by preincubation with cigarette smoke extract. Interestingly, serum starvation also induced CXCR3 up-regulation and enhanced EMAP II–induced endothelial apoptosis. Signal transduction via p38 mitogen-activated protein kinase activation was essential for CXCR3-induced cell death, but not for CXCR3 receptor up-regulation by cigarette smoke. In turn, protein nitration was required for CXCR3 receptor up-regulation by cigarette smoke and consequently for subsequent CXCR3-induced cell death. In conclusion, the concerted up-regulation of proinflammatory EMAP II, IP-10, and CXCR3 by cigarette smoke could sustain a cascade of cell death that may promote the alveolar tissue loss noted in human emphysema. PMID:22936405

Tryptophol induces death receptor (DR) 5-mediated apoptosis in U937 cells.

PubMed

Inagaki, Shyuichiro; Morimura, Shigeru; Tang, Yueqin; Akutagawa, Hiroshi; Kida, Kenji

2007-08-01

Tryptophol is a natural component isolated from vinegar produced from the boiled extract of black soybean. We have reported that tryptophol induces apoptosis in U937 cells via activation of caspase-8 followed by caspase-3. Tryptophol, however, did not affect human peripheral blood lymphocytes (PBL). In this study, we found that tryptophol enhances formation of a death-inducing signaling complex including death receptor (DR) 5. Cell viability and induction of apoptosis by tryptophol was reduced by transfection with decoy receptor (DcR) 1. These results indicate that tryptophol induces apoptosis through DR5 and that the resistance of PBL to tryptophol-induced apoptosis might be due to competition from DcR1.

Social learning requires plasticity enhanced by fluoxetine through prefrontal Bdnf-TrkB signaling to limit aggression induced by post-weaning social isolation

PubMed Central

Umemori, Juzoh; Tóth, Máté; Biró, László; Miskolczi, Christina; Balázsfi, Diána; Zelena, Dóra; Castrén, Eero

2017-01-01

Escalated or abnormal aggression induced by early adverse experiences is a growing issue of social concern and urges the development of effective treatment strategies. Here we report that synergistic interactions between psychosocial and biological factors specifically ameliorate escalated aggression induced by early adverse experiences. Rats reared in isolation from weaning until early adulthood showed abnormal forms of aggression and social deficits that were temporarily ameliorated by re-socialization, but aggression again escalated in a novel environment. We demonstrate that when re-socialization was combined with the antidepressant fluoxetine, which has been shown to reactivate juvenile-like state of plasticity, escalated aggression was greatly attenuated, while neither treatment alone was effective. Early isolation induced a permanent, re-socialization resistant reduction in Bdnf expression in the amygdala and the infralimbic cortex. Only the combined treatment of fluoxetine and re-socialization was able to recover Bdnf expression via epigenetic regulation. Moreover, the behavior improvement after the combined treatment was dependent on TrkB activity. Combined treatment specifically strengthened the input from the ventral hippocampus to the mPFC suggesting that this pathway is an important mediator of the beneficial behavioral effects of the combined psychosocial and pharmacological treatment of abnormal aggression. Our findings suggest that synergy between pharmacological induction of plasticity and psychosocial rehabilitation could enhance the efficacy of therapies for pathological aggression. PMID:28685757

JS-K promotes apoptosis by inducing ROS production in human prostate cancer cells.

PubMed

Qiu, Mingning; Chen, Lieqian; Tan, Guobin; Ke, Longzhi; Zhang, Sai; Chen, Hege; Liu, Jianjun

2017-03-01

Reactive oxygen species (ROS) are chemical species that alter redox status, and are responsible for inducing carcinogenesis. The purpose of the present study was to assess the effects of the glutathione S transferase-activated nitric oxide donor prodrug, JS-K, on ROS accumulation and on proliferation and apoptosis in human prostate cancer cells. Cell proliferation and apoptosis, ROS accumulation and the activation of the mitochondrial signaling pathway were measured. The results demonstrated that JS-K may inhibit prostate cancer cell growth in a dose- and time-dependent manner, and induce ROS accumulation and apoptosis in a dose-dependent manner. With increasing concentrations of JS-K, expression of pro-apoptotic proteins increased, but Bcl-2 expression decreased. Additionally, the antioxidant N-acetylcysteine reversed JS-K-induced cell apoptosis; conversely, the pro-oxidant glutathione disulfide exacerbated JS-K-induced apoptosis. In conclusion, the data suggest that JS-K induces prostate cancer cell apoptosis by increasing ROS levels.

JS-K promotes apoptosis by inducing ROS production in human prostate cancer cells

PubMed Central

Qiu, Mingning; Chen, Lieqian; Tan, Guobin; Ke, Longzhi; Zhang, Sai; Chen, Hege; Liu, Jianjun

2017-01-01

Reactive oxygen species (ROS) are chemical species that alter redox status, and are responsible for inducing carcinogenesis. The purpose of the present study was to assess the effects of the glutathione S transferase-activated nitric oxide donor prodrug, JS-K, on ROS accumulation and on proliferation and apoptosis in human prostate cancer cells. Cell proliferation and apoptosis, ROS accumulation and the activation of the mitochondrial signaling pathway were measured. The results demonstrated that JS-K may inhibit prostate cancer cell growth in a dose- and time-dependent manner, and induce ROS accumulation and apoptosis in a dose-dependent manner. With increasing concentrations of JS-K, expression of pro-apoptotic proteins increased, but Bcl-2 expression decreased. Additionally, the antioxidant N-acetylcysteine reversed JS-K-induced cell apoptosis; conversely, the pro-oxidant glutathione disulfide exacerbated JS-K-induced apoptosis. In conclusion, the data suggest that JS-K induces prostate cancer cell apoptosis by increasing ROS levels. PMID:28454225

Adolescence fluoxetine increases serotonergic activity in the raphe-hippocampus axis and improves depression-like behaviors in female rats that experienced neonatal maternal separation.

PubMed

Yoo, Sang Bae; Kim, Bom-Taeck; Kim, Jin Young; Ryu, Vitaly; Kang, Dong-Won; Lee, Jong-Ho; Jahng, Jeong Won

2013-06-01

This study was conducted to examine if fluoxetine, a selective 5-hydroxytryptamine (5-HT) reuptake inhibitor, would reverse adverse behavioral effects of neonatal maternal separation in female rats. Sprague-Dawley pups were separated from dam daily for 3h during postnatal day (PND) 1-14 (maternal separation; MS) or left undisturbed (non-handled; NH). Female NH and MS pups received intraperitoneal injection of fluoxetine (10mg/kg) or vehicle daily from PND 35 until the end of the whole experimental period. Rats were either subjected to behavioral tests during PND 44-54, or sacrificed for neurochemical analyses during PND 43-45. Daily food intake and weight gain of both NH and MS pups were suppressed by fluoxetine, with greater effects in MS pups. MS experience increased immobility and decrease swimming in forced swim test. Swimming was increased, although immobility was not significantly decreased, in MS females by adolescence fluoxetine. However, adolescence fluoxetine increased immobility during forced swim test and decreased time spent in open arms during elevated plus maze test in NH females. Fluoxetine normalized MS-induced decrease of the raphe 5-HT levels and increased 5-HT metabolism in the hippocampus in MS females, and increased the hypothalamic 5-HT both in NH and MS. Fluoxetine decreased the raphe 5-HT and increased the plasma corticosterone in NH females. Results suggest that decreased 5-HTergic activity in the raphe nucleus is implicated in the pathophysiology of depression-like behaviors, and increased 5-HTergic activities in the raphe-hippocampus axis may be a part of anti-depressant efficacy of fluoxetine, in MS females. Also, an extra-hypothalamic 5-HTergic activity may contribute to the increased anorectic efficacy of fluoxetine in MS females. Additionally, decreased 5-HT in the raphe and elevated plasma corticosterone may be related with fluoxetine-induced depression- and/or anxiety-like behaviors in NH females. Copyright © 2012 Elsevier Ltd

Ceramide-Induced Apoptosis in Renal Tubular Cells: A Role of Mitochondria and Sphingosine-1-Phoshate

PubMed Central

Ueda, Norishi

2015-01-01

Ceramide is synthesized upon stimuli, and induces apoptosis in renal tubular cells (RTCs). Sphingosine-1 phosphate (S1P) functions as a survival factor. Thus, the balance of ceramide/S1P determines ceramide-induced apoptosis. Mitochondria play a key role for ceramide-induced apoptosis by altered mitochondrial outer membrane permeability (MOMP). Ceramide enhances oligomerization of pro-apoptotic Bcl-2 family proteins, ceramide channel, and reduces anti-apoptotic Bcl-2 proteins in the MOM. This process alters MOMP, resulting in generation of reactive oxygen species (ROS), cytochrome C release into the cytosol, caspase activation, and apoptosis. Ceramide regulates apoptosis through mitogen-activated protein kinases (MAPKs)-dependent and -independent pathways. Conversely, MAPKs alter ceramide generation by regulating the enzymes involving ceramide metabolism, affecting ceramide-induced apoptosis. Crosstalk between Bcl-2 family proteins, ROS, and many signaling pathways regulates ceramide-induced apoptosis. Growth factors rescue ceramide-induced apoptosis by regulating the enzymes involving ceramide metabolism, S1P, and signaling pathways including MAPKs. This article reviews evidence supporting a role of ceramide for apoptosis and discusses a role of mitochondria, including MOMP, Bcl-2 family proteins, ROS, and signaling pathways, and crosstalk between these factors in the regulation of ceramide-induced apoptosis of RTCs. A balancing role between ceramide and S1P and the strategy for preventing ceramide-induced apoptosis by growth factors are also discussed. PMID:25751724

Effect of co-treatment with fluoxetine or mirtazapine and risperidone on the active behaviors and plasma corticosterone concentration in rats subjected to the forced swim test.

PubMed

Rogóż, Zofia; Kabziński, Marcin; Sadaj, Witold; Rachwalska, Paulina; Gądek-Michalska, Anna

2012-01-01

Several clinical reports have postulated a beneficial effect of the addition of a low dose of risperidone to the ongoing treatment with antidepressants in treatment-resistant depression. The present study aimed to examine the effect of treatment with fluoxetine or mirtazapine, given separately or jointly with risperidone, on active behavior and plasma corticosterone level in male Wistar rats subjected to the forced swim test (FST). The obtained results showed that fluoxetine (5 mg/kg), mirtazapine (5 and 10 mg/kg) or risperidone (0.05 and 0.1 mg/kg) did not change the active behavior of rats in the FST. However, co-treatment with fluoxetine (10 mg/kg) and risperidone (0.1 mg/kg) induced an antidepressant-like effect in that test because it significantly increased the swimming time and decreased the immobility time, while combined treatment with mirtazapine at 5 and 10 mg/kg and risperidone at 0.05 and 0.1 mg/kg evoked a significant increase in the swimming time and also climbing, and decreased the immobility time. WAY 100635 (a 5-HT(1A) receptor antagonist) at a dose of 0.1 mg/kg inhibited the antidepressant-like effect induced by co-administration of fluoxetine or mirtazapine and risperidone. Active behavior in that test did not reflect an increase in general activity, since combined treatment with fluoxetine or mirtazapine and risperidone failed to enhance the exploratory activity of rats. Co-treatment with fluoxetine or mirtazapine and risperidone did not reduce the stress-induced increase in plasma corticosterone concentration in animals subjected to the FST. The obtained results indicate that risperidone applied in a low dose enhances the antidepressant-like activity of fluoxetine and mirtazapine in the FST (but does not normalize the stress-induced increase in corticosterone level in these rats), and that 5-HT(1A) receptors may play some role in these effects.

c-Myc-induced apoptosis in fibroblasts is inhibited by specific cytokines.

PubMed Central

Harrington, E A; Bennett, M R; Fanidi, A; Evan, G I

1994-01-01

We have investigated the mechanism by which deregulated expression of c-Myc induces death by apoptosis in serum-deprived fibroblasts. We demonstrate that Myc-induced apoptosis in low serum is inhibited by a restricted group of cytokines, principally the insulin-like growth factors and PDGF. Cytokine-mediated protection from apoptosis is not linked to the cytokines' abilities to promote growth. Protection from apoptosis is evident in the post-commitment (mitogen-independent) S/G2/M phases of the cell cycle and also in cells that are profoundly blocked in cell cycle progression by drugs. Moreover, IGF-I inhibition of apoptosis occurs in the absence of protein synthesis, and so does not require immediate early gene expression. We conclude that c-Myc-induced apoptosis does not result from a conflict of growth signals but appears to be a normal physiological aspect of c-Myc function whose execution is regulated by the availability of survival factors. We discuss the possible implications of these findings for models of mammalian cell growth in vivo. Images PMID:8045259

O-GlcNAcylation regulates ischemia-induced neuronal apoptosis through AKT signaling.

PubMed

Shi, Jianhua; Gu, Jin-hua; Dai, Chun-ling; Gu, Jianlan; Jin, Xiaoxia; Sun, Jianming; Iqbal, Khalid; Liu, Fei; Gong, Cheng-Xin

2015-09-28

Apoptosis plays an important role in neural development and neurological disorders. In this study, we found that O-GlcNAcylation, a unique protein posttranslational modification with O-linked β-N-acetylglucosamine (GlcNAc), promoted apoptosis through attenuating phosphorylation/activation of AKT and Bad. By using co-immunoprecipitation and mutagenesis techniques, we identified O-GlcNAc modification at both Thr308 and Ser473 of AKT. O-GlcNAcylation-induced apoptosis was attenuated by over-expression of AKT. We also found a dynamic elevation of protein O-GlcNAcylation during the first four hours of cerebral ischemia, followed by continuous decline after middle cerebral artery occlusion (MCAO) in the mouse brain. The elevation of O-GlcNAcylation coincided with activation of cell apoptosis. Finally, we found a negative correlation between AKT phosphorylation and O-GlcNAcylation in ischemic brain tissue. These results indicate that cerebral ischemia induces a rapid increase of O-GlcNAcylation that promotes apoptosis through down-regulation of AKT activity. These findings provide a novel mechanism through which O-GlcNAcylation regulates ischemia-induced neuronal apoptosis through AKT signaling.

Infrasound exposure induces apoptosis of rat cardiac myocytes by regulating the expression of apoptosis-related proteins.

PubMed

Pei, Zhao-Hui; Chen, Bao-Ying; Tie, Ru; Zhang, Hai-Feng; Zhao, Ge; Qu, Ping; Zhu, Xiao-Xing; Zhu, Miao-Zhang; Yu, Jun

2011-12-01

It has been reported that exposure to infrasound causes cardiac dysfunction. Allowing for the key role of apoptosis in the pathogenesis of cardiovascular diseases, the objective of this study was to investigate the apoptotic effects of infrasound. Cardiac myocytes cultured from neonatal rats were exposed to infrasound of 5 Hz at 130 dB. The apoptosis was determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling. Also, the expression levels of a series of apoptosis-related proteins were detected. As a result, infrasound induced apoptosis of cultured rat cardiac myocytes in a time-dependant manner. The expression of proapoptotic proteins such as Bax, caspase-3, caspase-8, caspase-9, and FAS was significantly up-regulated, with concomitant down-regulated expression of antiapoptotic proteins such as Bcl-x, and the inhibitory apoptosis proteins family proteins including XIAP, cIAP-1, and cIAP-2. The expression of poly (ADP-ribose) polymerase and β-catenin, which are the substrate proteins of caspase-3, was significantly decreased. In conclusion, infrasound is an apoptotic inducer of cardiac myocytes.

Noxa/Mcl-1 Balance Regulates Susceptibility of Cells to Camptothecin-Induced Apoptosis1

PubMed Central

Mei, Yide; Xie, Chongwei; Xie, Wei; Tian, Xu; Li, Mei; Wu, Mian

2007-01-01

Although camptothecin (CPT) has been reported to induce apoptosis in various cancer cells, the molecular details of this regulation remain largely unknown. In this study, we demonstrate that BH3-only protein Noxa is upregulated during CPT-induced apoptosis, which is independent of p53. In addition, we show that phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway is responsible for Noxa's induction. Luciferase assay and cAMP response element binding protein (CREB) knockdown experiments further demonstrate that CREB is involved in the transcriptional upregulation of Noxa. Moreover, blocking Noxa expression using specific small interfering ribonucleic acid (siRNA) significantly reduces the apoptosis in response to CPT, indicating that Noxa is an essential mediator for CPT-induced apoptosis. Interestingly, antiapoptotic Mcl-1 was also upregulated through PI3K/Akt signaling pathway upon CPT treatment. Using immunoprecipitation assay, Noxa was found to interact with Mcl-1 in the presence or absence of CPT. Knockdown of Mcl-1 expression by short hairpin ribonucleic acid (shRNA) was shown to potentiate CPT-induced apoptosis. Consistently, ectopic overexpression of Mcl-1 rescued cells from apoptosis induced by CPT. Cells coexpressing Noxa and Mcl-1 at different ratio correlates well with the extent of apoptosis, suggesting that the balance between Noxa and Mcl-1 may determine the susceptibility of HeLa cells to CPT-induced apoptosis. PMID:17971907

Knockdown of HIF-1α and IL-8 induced apoptosis of hepatocellular carcinoma triggers apoptosis of vascular endothelial cells.

PubMed

Choi, Sung Hoon; Park, Jun Yong; Kang, Wonseok; Kim, Seung Up; Kim, Do Young; Ahn, Sang Hoon; Ro, Simon Wonsang; Han, Kwang-Hyub

2016-01-01

A local hypoxic microenvironment is one of the most important characteristics of solid tumors. Hypoxia inducible factor-1α (HIF-1α) and Interleukin-8 (IL-8) activate tumor survival from hypoxic-induced apoptosis in each pathway. This study aimed to evaluate whether knockdown of HIF-1α and IL-8 induced apoptosis of the hepatocellular carcinoma (HCC) and endothelial cell lines. HCC cell lines were infected with adenovirus-expressing shRNA for HIF-1α and IL-8 and maintained under hypoxic conditions (1% O2, 24 h). The expression levels of HIF-1α and both apoptotic and growth factors were examined by real-time quantitative PCR and western blot. We also investigated apoptosis by TUNEL assay (FACS and Immunofluorescence) and measured the concentration of cytochrome C. Inhibition of HIF-1α and IL-8 up-regulated the expression of apoptotic factors while downregulating anti-apoptotic factors simultaneously. Knockdown of HIF-1α and IL-8 increased the concentration of cytochrome C and enhanced DNA fragmentation in HCC cell lines. Moreover, culture supernatant collected from the knockdown of HIF-1α and IL-8 in HCC cell lines induced apoptosis in human umbilical vein endothelial cells under hypoxia, and the expression of variable apoptotic ligand increased from HCC cell lines, time-dependently. These data suggest that adenovirus-mediated knockdown of HIF-1α and IL-8 induced apoptosis in HCC cells and triggered apoptosis of vascular endothelial cells.

Mechanisms of methicillin-resistant Staphylococcus aureus pneumonia-induced intestinal epithelial apoptosis

PubMed Central

Perrone, Erin E.; Jung, Enjae; Breed, Elise; Dominguez, Jessica A.; Liang, Zhe; Clark, Andrew T.; Dunne, W. Michael; Burd, Eileen M.; Coopersmith, Craig M.

2012-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) pneumonia-induced sepsis is a common cause of morbidity in the intensive care unit. Although pneumonia is initiated in the lungs, extrapulmonary manifestations occur commonly. In light of the key role the intestine plays in the pathophysiology of sepsis, we sought to determine whether MRSA pneumonia induces intestinal injury. FVB/N mice were subjected to MRSA or sham pneumonia and sacrificed 24 hours later. Septic animals had a marked increase in intestinal epithelial apoptosis by both H&E and active caspase-3 staining. MRSA-induced intestinal apoptosis was associated with an increase in the expression of the pro-apoptotic proteins Bid and Bax and the anti-apoptotic protein Bcl-xL in the mitochondrial pathway. In the receptor-mediated pathway, MRSA pneumonia induced an increase in Fas-ligand but decreased protein levels of Fas, FADD, pFADD, TNF-R1 and TRADD. To assess the functional significance of these changes, MRSA pneumonia was induced in mice with genetic manipulations in proteins in either the mitochondrial or receptor-mediated pathways. Both Bid−/− mice and animals with intestine specific overexpression of Bcl-2 had decreased intestinal apoptosis compared to wild type animals. In contrast, Fas-ligand−/− mice had no alterations in apoptosis. To determine if these findings were organism-specific, similar experiments were performed in mice subjected to Pseudomonas aeruginosa pneumonia. P. aeruginosa induced gut apoptosis, but unlike MRSA, this was associated with increased Bcl-2 and TNF-R1 and decreased Fas. MRSA pneumonia thus induces organism-specific changes in intestinal apoptosis via changes in both the mitochondrial and receptor-mediated pathways although the former may be more functionally significant. PMID:22592747

Mechanisms of methicillin-resistant Staphylococcus aureus pneumonia-induced intestinal epithelial apoptosis.

PubMed

Perrone, Erin E; Jung, Enjae; Breed, Elise; Dominguez, Jessica A; Liang, Zhe; Clark, Andrew T; Dunne, W Michael; Burd, Eileen M; Coopersmith, Craig M

2012-07-01

Methicillin-resistant Staphylococcus aureus (MRSA) pneumonia-induced sepsis is a common cause of morbidity in the intensive care unit. Although pneumonia is initiated in the lungs, extrapulmonary manifestations occur commonly. In light of the key role the intestine plays in the pathophysiology of sepsis, we sought to determine whether MRSA pneumonia induces intestinal injury. FVB/N mice were subjected to MRSA or sham pneumonia and killed 24 h later. Septic animals had a marked increase in intestinal epithelial apoptosis by both hematoxylin-eosin and active caspase 3 staining. Methicillin-resistant S. aureus-induced intestinal apoptosis was associated with an increase in the expression of the proapoptotic proteins Bid and Bax and the antiapoptotic protein Bcl-xL in the mitochondrial pathway. In the receptor-mediated pathway, MRSA pneumonia induced an increase in Fas ligand but decreased protein levels of Fas, FADD, pFADD, TNF-R1, and TRADD. To assess the functional significance of these changes, MRSA pneumonia was induced in mice with genetic manipulations in proteins in either the mitochondrial or receptor-mediated pathways. Both Bid-/- mice and animals with intestine-specific overexpression of Bcl-2 had decreased intestinal apoptosis compared with wild-type animals. In contrast, Fas ligand-/- mice had no alterations in apoptosis. To determine if these findings were organism-specific, similar experiments were performed in mice subjected to Pseudomonas aeruginosa pneumonia. Pseudomonas aeruginosa induced gut apoptosis, but unlike MRSA, this was associated with increased Bcl-2 and TNF-R1 and decreased Fas. Methicillin-resistant S. aureus pneumonia thus induces organism-specific changes in intestinal apoptosis via changes in both the mitochondrial and receptor-mediated pathways, although the former may be more functionally significant.

From selective to highly selective SSRIs: a comparison of the antinociceptive properties of fluoxetine, fluvoxamine, citalopram and escitalopram.

PubMed

Schreiber, Shaul; Pick, Chaim G

2006-08-01

Most Serotonin Selective Reuptake Inhibitors (SSRIs) have been found to possess secondary binding properties, while citalopram and its S-enantiomer (escitalopram) have been reconfirmed "purest SSRIs". Using the mouse model of acute pain hotplate analgesia meter, we evaluated the antinociceptive properties of fluoxetine, fluvoxamine, citalopram and escitalopram, injected i.p. Fluvoxamine induced a dose-dependent clear antinociceptive effect (with an ED(50) value of 6.4 mg/kg). Both fluoxetine and citalopram induced (separately) only a weak antinociceptive effect with an inverse "U" shape curve. All three drug's effects were not abolished by naloxone. Escitalopram did not elicit any effect at quasi-equipotent doses. These findings show that fluoxetine, fluvoxamine and citalopram given i.p. are weak antinociceptors, (not mediated through opioid mechanisms), while escitalopram possesses no antinociceptive properties when injected i.p. This difference between citalopram and escitalopram calls for further studies in order to assess the various differences between the two enantiomers of citalopram, and between each enantiomer and the racemic mixture.

Myosin IIA-related Actomyosin Contractility Mediates Oxidative Stress-induced Neuronal Apoptosis

PubMed Central

Wang, Yan; Xu, Yingqiong; Liu, Qian; Zhang, Yuanyuan; Gao, Zhen; Yin, Mingzhu; Jiang, Nan; Cao, Guosheng; Yu, Boyang; Cao, Zhengyu; Kou, Junping

2017-01-01

Oxidative stress-induced neuronal apoptosis plays an important role in the progression of central nervous system (CNS) diseases. In our study, when neuronal cells were exposed to hydrogen peroxide (H2O2), an exogenous oxidant, cell apoptosis was observed with typical morphological changes including membrane blebbing, neurite retraction and cell contraction. The actomyosin system is considered to be responsible for the morphological changes, but how exactly it regulates oxidative stress-induced neuronal apoptosis and the distinctive functions of different myosin II isoforms remain unclear. We demonstrate that myosin IIA was required for neuronal contraction, while myosin IIB was required for neuronal outgrowth in normal conditions. During H2O2-induced neuronal apoptosis, myosin IIA, rather than IIB, interacted with actin filaments to generate contractile forces that lead to morphological changes. Moreover, myosin IIA knockout using clustered regularly interspaced short palindromic repeats/CRISPR-associated protein-9 nuclease (CRISPR/Cas9) reduced H2O2-induced neuronal apoptosis and the associated morphological changes. We further demonstrate that caspase-3/Rho-associated kinase 1 (ROCK1) dependent phosphorylation of myosin light chain (MLC) was required for the formation of the myosin IIA-actin complex. Meanwhile, either inhibition of myosin II ATPase with blebbistatin or knockdown of myosin IIA with siRNA reversely attenuated caspase-3 activation, suggesting a positive feedback loop during oxidative stress-induced apoptosis. Based on our observation, myosin IIA-actin complex contributes to actomyosin contractility and is associated with the positive feedback loop of caspase-3/ROCK1/MLC pathway. This study unravels the biochemical and mechanistic mechanisms during oxidative stress-induced neuronal apoptosis and may be applicable for the development of therapies for CNS diseases. PMID:28352215

Platinum Nanoparticles Induce Apoptosis on Raw 264.7 Macrophage Cells.

PubMed

Loan, Ta Thi; Do, Le Thanh; Yoo, Hoon

2018-02-01

The cellular effects of platinum nanoparticles (PNP05, average size of 5 nm, and PNP30, average size of 30 nm) were investigated on murine leukemia Raw 264.7 cells. Cells treated with various concentrations of PNPs showed size-dependent cytotoxicity in an MTT assay with PNP5 of smaller nanoparticles higher toxicity than PNP30. Investigations on cell morphology, Annexin V assay, DNA fragmentation and the activity of caspase-3/-7 showed that PNPs induced apoptosis on Raw 264.7 cells by changing cell morphology and density, increasing cell population in apoptosis and causing nucleus fragmentation. Further study on caspase activity by Western blotting revealed that the apoptosis was induced by the activation of caspase-3 and -7. In addition, PNPs inactivated DNA repair system, generating dose-dependent DNA ladder bands on agarose gel electrophoresis. Taken together, PNPs triggered cytotoxicity on Raw 264.7 cells by suppressing cell growth/survival and inducing apoptosis.

[Study on thaspine in inducing apoptosis of A549 cell].

PubMed

Zhang, Yan-min; He, Lang-chong

2007-04-01

To investigate the effect of thaspine on the cellular proliferation, apoptosis and cell cycle in A549 cell line. A549 cell was cultured with different concentrations of thaspine. Cellular proliferation was detected with MTT, apoptosis and cell cycle were checked with Flow Cytometer, and change of microstructure was observed by transmission electron microscope. Thaspine could inhibit the proliferation and induce apoptosis of A549 cell in a time-dose dependent manner. Cell cycle was significantly stopped at the S phase by thaspine with FCM technology. Under electronic microscope, the morphology of A549 cell showed nuclear karyopycnosis, chromatin agglutination and typical apoptotic body when the cell was treated with thaspine. Thaspine has the effects of anti-tumor and inducing apoptosis.

Evaluation of the neuronal apoptotic pathways involved in cytoskeletal disruption-induced apoptosis.

PubMed

Jordà, Elvira G; Verdaguer, Ester; Jimenez, Andrés; Arriba, S Garcia de; Allgaier, Clemens; Pallàs, Mercè; Camins, Antoni

2005-08-01

The cytoskeleton is critical to neuronal functioning and survival. Cytoskeletal alterations are involved in several neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. We studied the possible pathways involved in colchicine-induced apoptosis in cerebellar granule neurons (CGNs). Although colchicine evoked an increase in caspase-3, caspase-6 and caspase-9 activation, selective caspase inhibitors did not attenuate apoptosis. Inhibitors of other cysteine proteases such as PD150606 (a calpain-specific inhibitor), Z-Phe-Ala fluoromethyl ketone (a cathepsins-inhibitors) and N(alpha)-p-tosyl-l-lysine chloromethyl ketone (serine-proteases inhibitor) also had no effect on cell death/apoptosis induced by colchicine. However, BAPTA-AM 10 microM (intracellular calcium chelator) prevented apoptosis mediated by cytoskeletal alteration. These data indicate that calcium modulates colchicine-induced apoptosis in CGNs. PARP-1 inhibitors did not prevent apoptosis mediated by colchicine. Finally, colchicine-induced apoptosis in CGNs was attenuated by kenpaullone, a cdk5 inhibitor. Kenpaullone and indirubin also prevented cdk5/p25 activation mediated by colchicine. These findings indicate that cytoskeletal alteration can compromise cdk5 activation, regulating p25 formation and suggest that cdk5 inhibitors attenuate apoptosis mediated by cytoskeletal alteration. The present data indicate the potential therapeutic value of drugs that prevent the formation of p25 for the treatment of neurodegenerative disorders.

Influenza virus induces apoptosis via BAD-mediated mitochondrial dysregulation.

PubMed

Tran, Anh T; Cortens, John P; Du, Qiujiang; Wilkins, John A; Coombs, Kevin M

2013-01-01

Influenza virus infection results in host cell death and major tissue damage. Specific components of the apoptotic pathway, a signaling cascade that ultimately leads to cell death, are implicated in promoting influenza virus replication. BAD is a cell death regulator that constitutes a critical control point in the intrinsic apoptosis pathway, which occurs through the dysregulation of mitochondrial outer membrane permeabilization and the subsequent activation of downstream apoptogenic factors. Here we report a novel proviral role for the proapoptotic protein BAD in influenza virus replication. We show that influenza virus-induced cytopathology and cell death are considerably inhibited in BAD knockdown cells and that both virus replication and viral protein production are dramatically reduced, which suggests that virus-induced apoptosis is BAD dependent. Our data showed that influenza viruses induced phosphorylation of BAD at residues S112 and S136 in a temporal manner. Viral infection also induced BAD cleavage, late in the viral life cycle, to a truncated form that is reportedly a more potent inducer of apoptosis. We further demonstrate that knockdown of BAD resulted in reduced cytochrome c release and suppression of the intrinsic apoptotic pathway during influenza virus replication, as seen by an inhibition of caspases-3, caspase-7, and procyclic acidic repetitive protein (PARP) cleavage. Our data indicate that influenza viruses carefully modulate the activation of the apoptotic pathway that is dependent on the regulatory function of BAD and that failure of apoptosis activation resulted in unproductive viral replication.

Influenza Virus Induces Apoptosis via BAD-Mediated Mitochondrial Dysregulation

PubMed Central

Tran, Anh T.; Cortens, John P.; Du, Qiujiang; Wilkins, John A.

2013-01-01

Influenza virus infection results in host cell death and major tissue damage. Specific components of the apoptotic pathway, a signaling cascade that ultimately leads to cell death, are implicated in promoting influenza virus replication. BAD is a cell death regulator that constitutes a critical control point in the intrinsic apoptosis pathway, which occurs through the dysregulation of mitochondrial outer membrane permeabilization and the subsequent activation of downstream apoptogenic factors. Here we report a novel proviral role for the proapoptotic protein BAD in influenza virus replication. We show that influenza virus-induced cytopathology and cell death are considerably inhibited in BAD knockdown cells and that both virus replication and viral protein production are dramatically reduced, which suggests that virus-induced apoptosis is BAD dependent. Our data showed that influenza viruses induced phosphorylation of BAD at residues S112 and S136 in a temporal manner. Viral infection also induced BAD cleavage, late in the viral life cycle, to a truncated form that is reportedly a more potent inducer of apoptosis. We further demonstrate that knockdown of BAD resulted in reduced cytochrome c release and suppression of the intrinsic apoptotic pathway during influenza virus replication, as seen by an inhibition of caspases-3, caspase-7, and procyclic acidic repetitive protein (PARP) cleavage. Our data indicate that influenza viruses carefully modulate the activation of the apoptotic pathway that is dependent on the regulatory function of BAD and that failure of apoptosis activation resulted in unproductive viral replication. PMID:23135712

Behavioral and neurogenomic transcriptome changes in wild-derived zebrafish with fluoxetine treatment

PubMed Central

2013-01-01

Background Stress and anxiety-related behaviors are seen in many organisms. Studies have shown that in humans and other animals, treatment with selective serotonin reuptake inhibitors (e.g. fluoxetine) can reduce anxiety and anxiety-related behaviors. The efficacies and side effects, however, can vary between individuals. Fluoxetine can modulate anxiety in a stereospecific manner or with equal efficacy regardless of stereoisomer depending on the mechanism of action (e.g. serotonergic or GABAergic effects). Zebrafish are an emerging and valuable translational model for understanding human health related issues such as anxiety. In this study we present data showing the behavioral and whole brain transcriptome changes with fluoxetine treatment in wild-derived zebrafish and suggest additional molecular mechanisms of this widely-prescribed drug. Results We used automated behavioral analyses to assess the effects of racemic and stereoisomeric fluoxetine on male wild-derived zebrafish. Both racemic and the individual isomers of fluoxetine reduced anxiety-related behaviors relative to controls and we did not observe stereospecific fluoxetine effects. Using RNA-sequencing of the whole brain, we identified 411 genes showing differential expression with racemic fluoxetine treatment. Several neuropeptides (neuropeptide Y, isotocin, urocortin 3, prolactin) showed consistent expression patterns with the alleviation of stress and anxiety when anxiety-related behavior was reduced with fluoxetine treatment. With gene ontology and KEGG pathway analyses, we identified lipid and amino acid metabolic processes, and steroid biosynthesis among other terms to be over-enriched. Conclusion Our results demonstrate that fluoxetine reduces anxiety-related behaviors in wild-derived zebrafish and alters their neurogenomic state. We identify two biological processes, lipid and amino acid metabolic synthesis that characterize differences in the fluoxetine treated fish. Fluoxetine may be acting on

Gastrointestinal Hemorrhage Related to Fluoxetine in a Patient With Stroke.

PubMed

Wee, Tze Chao

2017-11-01

We report on a patient who developed massive gastrointestinal hemorrhage related to the use of fluoxetine in combination with aspirin and clopidogrel. A 58-year-old man was admitted with a posterior circulation infarct with significant weakness in all four limbs and dysarthria. Aspirin and clopidogrel were started. Fluoxetine was started for pharmacological neurostimulation to promote motor recovery and for low mood. He developed gastrointestinal hemorrhage a week after fluoxetine was started. Fluoxetine was suspended and investigations failed to reveal the source of the bleeding. He was then restarted on fluoxetine along with dual antiplatelets, and gastrointestinal hemorrhage recurred after 1 week. He was extensively investigated for a source of gastrointestinal hemorrhage, and again no source could be identified. Eventually, fluoxetine was switched to mirtazapine with no further gastrointestinal hemorrhage. He remained on dual antiplatelets. A number of case-control and cohort studies had identified the association of gastrointestinal hemorrhage with the use of selective serotonin reuptake inhibitor (SSRI). We hope to raise awareness of this association in physical medicine and rehabilitation physicians as the use of SSRI is expected to rise.

Berberine potentizes apoptosis induced by X-rays irradiation probably through modulation of gap junctions.

PubMed

Liu, Bing; Wang, Qin; Yuan, Dong-dong; Hong, Xiao-ting; Tao, Liang

2011-04-01

Clinical combination of some traditional Chinese medical herbs, including berberine, with irradiation is demonstrated to improve efficacy of tumor radiotherapy, yet the mechanisms for such effect remain largely unknown. The present study investigated the effect of berberine on apoptosis induced by X-rays irradiation and the relation between this effect and gap junction intercellular communication (GJIC). The role of gap junctions in the modulation of X-rays irradiation-induced apoptosis was explored by manipulation of connexin (Cx) expression, and gap junction function, using oleamide, a GJIC inhibitor, and berberine. In transfected HeLa cells, Cx32 expression increased apoptosis induced by X-rays irradiation, while inhibition of gap junction by oleamide reduced the irradiation responses, indicating the dependence of X-rays irradiation-induced apoptosis on GJIC. Berberine, at the concentrations without cytotoxicity, enhanced apoptosis induced by irradiation only in the presence of functional gap junctions. These results suggest that berberine potentizes cell apoptosis induced by X-rays irradiation, probably through enhancement of gap junction activity.

Correlation between radio-induced lymphocyte apoptosis measurements obtained from two French centres.

PubMed

Mirjolet, C; Merlin, J L; Dalban, C; Maingon, P; Azria, D

2016-07-01

In the era of modern treatment delivery, increasing the dose delivered to the target to improve local control might be modulated by the patient's intrinsic radio-sensitivity. A predictive assay based on radio-induced lymphocyte apoptosis quantification highlighted the significant correlation between CD4 and CD8 T-lymphocyte apoptosis and grade 2 or 3 radiation-induced late toxicities. By conducting this assay at several technical platforms, the aim of this study was to demonstrate that radio-induced lymphocyte apoptosis values obtained from two different platforms were comparable. For 25 patients included in the PARATOXOR trial running in Dijon the radio-induced lymphocyte apoptosis results obtained from the laboratory of Montpellier (IRCM, Inserm U1194, France), considered as the reference (referred to as Lab 1), were compared with those from the laboratory located at the Institut de cancérologie de Lorraine (ICL, France), referred to as Lab 2. Different statistical methods were used to measure the agreement between the radio-induced lymphocyte apoptosis data from the two laboratories (quantitative data). The Bland-Altman plot was used to identify potential bias. All statistical tests demonstrated good agreement between radio-induced lymphocyte apoptosis values obtained from both sites and no major bias was identified. Since radio-induced lymphocyte apoptosis values, which predict tolerance to radiotherapy, could be assessed by two laboratories and showed a high level of robustness and consistency, we can suggest that this assay be extended to any laboratories that use the same technique. Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

Steroid Receptor Coactivator-interacting Protein (SIP) Inhibits Caspase-independent Apoptosis by Preventing Apoptosis-inducing Factor (AIF) from Being Released from Mitochondria*

PubMed Central

Wang, Dandan; Liang, Jing; Zhang, Yu; Gui, Bin; Wang, Feng; Yi, Xia; Sun, Luyang; Yao, Zhi; Shang, Yongfeng

2012-01-01

Apoptosis-inducing factor (AIF) is a caspase-independent death effector. Normally residing in the mitochondrial intermembrane space, AIF is released and translocated to the nucleus in response to proapoptotic stimuli. Nuclear AIF binds to DNA and induces chromatin condensation and DNA fragmentation, characteristics of apoptosis. Until now, it remained to be clarified how the mitochondrial-nuclear translocation of AIF is regulated. Here we report that steroid receptor coactivator-interacting protein (SIP) interacts directly with AIF in mitochondria and specifically inhibits caspase-independent and AIF-dependent apoptosis. Challenging cells with apoptotic stimuli leads to rapid degradation of SIP, and subsequently AIF is liberated from mitochondria and translocated to the nucleus to induce apoptosis. Together, our data demonstrate that SIP is a novel regulator in caspase-independent and AIF-mediated apoptosis. PMID:22371500

Apoptosis-inducing and apoptosis-preventing functions of poliovirus.

PubMed Central

Tolskaya, E A; Romanova, L I; Kolesnikova, M S; Ivannikova, T A; Smirnova, E A; Raikhlin, N T; Agol, V I

1995-01-01

Data showing that an apoptotic reaction (the exit into the cytoplasm and nucleolytic internucleosomal degradation of chromosomal DNA, compaction and fragmentation of chromatin, cellular shrinkage, and cytoplasmic blebbing) developed in a subline of HeLa-S3 cells upon nonpermissive poliovirus infection with either a guanidine-sensitive poliovirus in the presence of guanidine, a guanidine-dependent mutant in the absence of guanidine, or certain temperature-sensitive mutants at a restrictive temperature are presented. Essentially, no apoptotic reaction occurred upon permissive infection of these cells. Both permissive and nonpermissive infections resulted in the inhibition of host protein synthesis. Actinomycin D or cycloheximide also elicited a rapid apoptotic reaction in uninfected cells. However, preinfection or coinfection with poliovirus prevented the apoptotic response to the addition of actinomycin D, and preinfection blocked cycloheximide-induced apoptosis as well. These data fit a model in which the cells used are prepared to develop apoptosis, with their viability due to the presence of certain short-lived mRNA and protein species. Poliovirus infection turns on two oppositely directed sets of reactions. On the one hand, the balance is driven toward apoptosis, probably via the shutoff of host macromolecular synthesis. On the other hand, viral protein exhibits antiapoptotic activity, thereby preventing premature cell death. To our knowledge, this is the first description of an antiapoptotic function for an RNA virus. PMID:7529330

BH3-Only Protein BIM Mediates Heat Shock-Induced Apoptosis

PubMed Central

Mahajan, Indra M.; Chen, Miao-Der; Muro, Israel; Robertson, John D.; Wright, Casey W.; Bratton, Shawn B.

2014-01-01

Acute heat shock can induce apoptosis through a canonical pathway involving the upstream activation of caspase-2, followed by BID cleavage and stimulation of the intrinsic pathway. Herein, we report that the BH3-only protein BIM, rather than BID, is essential to heat shock-induced cell death. We observed that BIM-deficient cells were highly resistant to heat shock, exhibiting short and long-term survival equivalent to Bax−/−Bak−/− cells and better than either Bid−/− or dominant-negative caspase-9-expressing cells. Only Bim−/− and Bax−/−Bak−/− cells exhibited resistance to mitochondrial outer membrane permeabilization and loss of mitochondrial inner membrane potential. Moreover, while dimerized caspase-2 failed to induce apoptosis in Bid−/− cells, it readily did so in Bim−/− cells, implying that caspase-2 kills exclusively through BID, not BIM. Finally, BIM reportedly associates with MCL-1 following heat shock, and Mcl-1−/− cells were indeed sensitized to heat shock-induced apoptosis. However, pharmacological inhibition of BCL-2 and BCL-XL with ABT-737 also sensitized cells to heat shock, most likely through liberation of BIM. Thus, BIM mediates heat shock-induced apoptosis through a BAX/BAK-dependent pathway that is antagonized by antiapoptotic BCL-2 family members. PMID:24427286

Molecular mechanisms of hyperthermia-induced apoptosis enhanced by withaferin A.

PubMed

Cui, Zheng-Guo; Piao, Jin-Lan; Rehman, Mati U R; Ogawa, Ryohei; Li, Peng; Zhao, Qing-Li; Kondo, Takashi; Inadera, Hidekuni

2014-01-15

Hyperthermia is a good therapeutic tool for non-invasive cancer therapy; however, its cytotoxic effects are not sufficient. In the present study, withaferin A (WA), a steroidal lactone derived from the plant Withania somnifera Dunal, has been investigated for its possible enhancing effects on hyperthermia-induced apoptosis. In HeLa cells, treatment with 0.5 or 1.0μM WA at 44°C for 30min induced significant apoptosis accompanied by decreased intracellular GSH/GSSG ratio and caspase-3 activation, while heat or WA alone did not induce such changes. The upregulation in apoptosis was significantly inhibited by glutathione monoethyl ester, a cell permeable glutathione precursor. Mitochondrial transmembrane potentials were dramatically decreased by the combined treatment, with increases in pro-apoptotic Bcl-2-family proteins tBid and Noxa, and downregulation of antiapoptotic Bcl-2 and Mcl-1. Combined treatment with hyperthermia and WA induced significant increases in JNK phosphorylation (p-JNK), and decreases in the phosphorylation of ERK (p-ERK) compared with either treatment alone. These results suggest that WA enhances hyperthermia-induced apoptosis via a mitochondria-caspase-dependent pathway; its underlying mechanism involves elevated intracellular oxidative stress, mitochondria dysfunction, and JNK activation. © 2013 Elsevier B.V. All rights reserved.

Myostatin induces mitochondrial metabolic alteration and typical apoptosis in cancer cells

PubMed Central

Liu, Y; Cheng, H; Zhou, Y; Zhu, Y; Bian, R; Chen, Y; Li, C; Ma, Q; Zheng, Q; Zhang, Y; Jin, H; Wang, X; Chen, Q; Zhu, D

2013-01-01

Myostatin, a member of the transforming growth factor-β superfamily, regulates the glucose metabolism of muscle cells, while dysregulated myostatin activity is associated with a number of metabolic disorders, including muscle cachexia, obesity and type II diabetes. We observed that myostatin induced significant mitochondrial metabolic alterations and prolonged exposure of myostatin induced mitochondria-dependent apoptosis in cancer cells addicted to glycolysis. To address the underlying mechanism, we found that the protein levels of Hexokinase II (HKII) and voltage-dependent anion channel 1 (VDAC1), two key regulators of glucose metabolisms as well as metabolic stress-induced apoptosis, were negatively correlated. In particular, VDAC1 was dramatically upregulated in cells that are sensitive to myostatin treatment whereas HKII was downregulated and dissociated from mitochondria. Myostatin promoted the translocation of Bax from cytosol to mitochondria, and knockdown of VDAC1 inhibited myostatin-induced Bax translocation and apoptosis. These apoptotic changes can be partially rescued by repletion of ATP, or by ectopic expression of HKII, suggesting that perturbation of mitochondrial metabolism is causally linked with subsequent apoptosis. Our findings reveal novel function of myostatin in regulating mitochondrial metabolism and apoptosis in cancer cells. PMID:23412387

Temporal variability of glucocorticoid receptor activity is functionally important for the therapeutic action of fluoxetine in the hippocampus.

PubMed

Lee, M-S; Kim, Y-H; Park, W-S; Park, O-K; Kwon, S-H; Hong, K S; Rhim, H; Shim, I; Morita, K; Wong, D L; Patel, P D; Lyons, D M; Schatzberg, A F; Her, S

2016-02-01

Previous studies have shown inconsistent results regarding the actions of antidepressants on glucocorticoid receptor (GR) signalling. To resolve these inconsistencies, we used a lentiviral-based reporter system to directly monitor rat hippocampal GR activity during stress adaptation. Temporal GR activation was induced significantly by acute stress, as demonstrated by an increase in the intra-individual variability of the acute stress group compared with the variability of the non-stress group. However, the increased intra-individual variability was dampened by exposure to chronic stress, which was partly restored by fluoxetine treatment without affecting glucocorticoid secretion. Immobility in the forced-swim test was negatively correlated with the intra-individual variability, but was not correlated with the quantitative GR activity during fluoxetine therapy; this highlights the temporal variability in the neurobiological links between GR signalling and the therapeutic action of fluoxetine. Furthermore, we demonstrated sequential phosphorylation between GR (S224) and (S232) following fluoxetine treatment, showing a molecular basis for hormone-independent nuclear translocation and transcriptional enhancement. Collectively, these results suggest a neurobiological mechanism by which fluoxetine treatment confers resilience to the chronic stress-mediated attenuation of hypothalamic-pituitary-adrenal axis activity.

Sulfur mustard-induced apoptosis in hairless guinea pig skin.

PubMed

Kan, Robert K; Pleva, Christina M; Hamilton, Tracey A; Anderson, Dana R; Petrali, John P

2003-01-01

The present study was aimed to examine whether apoptosis is involved in the pathogenesis of sulfur mustard (SM)-induced basal cell death. Skin sites of the hairless guinea pig exposed to SM vapor for 8 minutes were harvested at 3, 6, 12, 24, and 48 hours postexposure. Immunohistochemical detection of basal cell apoptosis was performed using the ApopTag in situ apoptosis labeling kit. Only occasional apoptotic basal cells (BC)were observed in nonexposed and perilesional control sites. At lesional sites, apoptosis of BC was not detected at 3 hours postexposure. However, at 6 hours and 12 hours postexposure, 18% and 59% of BC were apoptotic, respectively. At 24 and 48 hours postexposure, individual apoptotic basal cells were not clearly recognizable due to necrosis. At the ultrastructural level, degenerating BC exhibited typical apoptotic morphology including nuclear condensation and chromatin margination. The results suggest that apoptotic cell death is a cytotoxic mechanism with the number of BC undergoing apoptosis significantly increasing from 6 to 12 hours postexposure. In addition, because necrosis is preferential at 24 hours postexposure, we believe that SM-induced cell death involves early apoptosis and late necrosis, which temporally overlap to produce a single cell death pathway along an apoptotic-necrotic continuum.

Pharmacokinetics of Fluoxetine in Pregnant Baboons (Papio spp.)

PubMed Central

Shoulson, Rivka L; Stark, Raymond L; Garland, Marianne

2014-01-01

Fluoxetine is used to treat a number of psychiatric conditions in humans and behavioral problems in animals. Its use in pregnancy must balance maternal benefit with potential risk to the fetus. Knowledge of adult and fetal drug disposition can assist clinicians in selecting therapy that minimizes adverse effects to the fetus. Nonhuman primate models are used frequently in drug dose-translation studies, and pregnancy in baboons has many similarities to human pregnancy. Accordingly, pharmacokinetic analysis of a series of fluoxetine and norfluoxetine administrations to pregnant baboons was performed. The mean maternal baboon steady-state clearance of fluoxetine (42 mL/min/kg) was considerably higher than that in humans. Norfluoxetine, the major active metabolite, had a higher metabolite-to-drug ratio (8.7) than that found in humans, particularly with oral dosing. These results are consistent with more extensive metabolism in baboons than in humans and leads to a higher clearance than would be expected from allometric scaling. Fetal-to-maternal fluoxetine and norfluoxetine ratios under steady-state conditions were similar to those in humans, with fetal concentrations of fluoxetine 42% and norfluoxetine 47% of maternal concentrations. The fetal clearance of fluoxetine (303 ± 176 mL/min) and norfluoxetine (450 mL/min) exceeded reported placental blood flow. Understanding these species-associated differences in metabolism is a prerequisite to extrapolating data between species. Nonetheless, nonhuman primates are likely to remain valuable models for pharmacokinetic studies during pregnancy, particularly those directed toward fetal neurodevelopmental effects. Our results also are applicable to determining appropriate dosing of nonhuman primates in clinical settings. PMID:25650979

Acute and chronic anxiogenic-like response to fluoxetine in rats in the elevated plus-maze: modulation by stressful handling.

PubMed

Robert, Gabriel; Drapier, Dominique; Bentué-Ferrer, Danièle; Renault, Alain; Reymann, Jean-Michel

2011-07-07

While antidepressants are widely prescribed to humans for the treatment of anxiety, the results achieved with animal anxiety models are conflicting. The experimental procedure and the prior test history of the animals are critical parameters that are largely susceptible to influence the results and their interpretation. We compared the effect of 5mg fluoxetine administered to six groups of rats subjected to the psychopharmacological test of the elevated plus-maze, under experimental conditions designed to demonstrate the effect of handling and one daily injection on the response to fluoxetine. The results show that for animals with the same recent experience, fluoxetine, when administered once or over a period of 15 days, induces anxiogenic-like behaviour. On the other hand, our results also show that stressful handling has an anxiolytic-like effect modulating the anxiogenic-like effect of fluoxetine, without eliminating it altogether. Copyright © 2011 Elsevier B.V. All rights reserved.

Efficacy and safety of olanzapine/fluoxetine combination vs fluoxetine monotherapy following successful combination therapy of treatment-resistant major depressive disorder.

PubMed

Brunner, Elizabeth; Tohen, Mauricio; Osuntokun, Olawale; Landry, John; Thase, Michael E

2014-10-01

This study assessed prevention of relapse in patients with treatment-resistant depression (TRD) taking olanzapine/fluoxetine combination (OFC). Patients with major depressive disorder (MDD) who failed to satisfactorily respond to ≥ 2 different antidepressants for ≥ 6 weeks within the current MDD episode were acutely treated for 6-8 weeks, followed by stabilization (12 weeks) on OFC. Those who remained stable were randomized to OFC or fluoxetine for up to 27 weeks. Time-to-relapse was the primary efficacy outcome defined as 50% increase in Montgomery-Åsberg Depression Rating Scale score with Clinical Global Impressions-Severity of Depression score of ≥ 4; hospitalization for depression or suicidality; or discontinuation for lack of efficacy or worsening of depression or suicidality. A total of 444 patients were randomized 1:1 to OFC (N=221) or fluoxetine (N=223). Time-to-relapse was significantly longer in OFC-treated patients compared with fluoxetine-treated patients (p<0.001). Treatment-emergent weight gain and some mean and categorical fasting metabolic changes were significantly greater in OFC-treated patients. Clinically significant weight gain (≥ 7%) was observed in 55.7% of patients who remained on OFC throughout the study, including the relapse-prevention phase (up to 47 weeks). There were no significant differences between patients treated with OFC and fluoxetine in extrapyramidal symptoms or serious adverse events. We believe this is the first controlled relapse-prevention study in subjects with TRD that supports continued use of a second-generation antipsychotic beyond stabilization. A thorough assessment of benefits and risks (in particular metabolic changes) associated with continuing treatment with OFC or fluoxetine must be done based on individual patient needs.

Efficacy and Safety of Olanzapine/Fluoxetine Combination vs Fluoxetine Monotherapy Following Successful Combination Therapy of Treatment-Resistant Major Depressive Disorder

PubMed Central

Brunner, Elizabeth; Tohen, Mauricio; Osuntokun, Olawale; Landry, John; Thase, Michael E

2014-01-01

This study assessed prevention of relapse in patients with treatment-resistant depression (TRD) taking olanzapine/fluoxetine combination (OFC). Patients with major depressive disorder (MDD) who failed to satisfactorily respond to ⩾2 different antidepressants for ⩾6 weeks within the current MDD episode were acutely treated for 6–8 weeks, followed by stabilization (12 weeks) on OFC. Those who remained stable were randomized to OFC or fluoxetine for up to 27 weeks. Time-to-relapse was the primary efficacy outcome defined as 50% increase in Montgomery-Åsberg Depression Rating Scale score with Clinical Global Impressions−Severity of Depression score of ⩾4; hospitalization for depression or suicidality; or discontinuation for lack of efficacy or worsening of depression or suicidality. A total of 444 patients were randomized 1:1 to OFC (N=221) or fluoxetine (N=223). Time-to-relapse was significantly longer in OFC-treated patients compared with fluoxetine-treated patients (p<0.001). Treatment-emergent weight gain and some mean and categorical fasting metabolic changes were significantly greater in OFC-treated patients. Clinically significant weight gain (⩾7%) was observed in 55.7% of patients who remained on OFC throughout the study, including the relapse-prevention phase (up to 47 weeks). There were no significant differences between patients treated with OFC and fluoxetine in extrapyramidal symptoms or serious adverse events. We believe this is the first controlled relapse-prevention study in subjects with TRD that supports continued use of a second-generation antipsychotic beyond stabilization. A thorough assessment of benefits and risks (in particular metabolic changes) associated with continuing treatment with OFC or fluoxetine must be done based on individual patient needs. PMID:24801768

Fasting-induced apoptosis in rat liver is blocked by cycloheximide.

PubMed

Tessitore, L; Tomasi, C; Greco, M

1999-08-01

The effect of cycloheximide (CH) on the fasting-induced changes of rat liver cell and protein turnover has been investigated. Late starvation phase (3-4-day-fasting period) was characterised by a decrease in liver weight and protein and DNA content. The loss of DNA was not related to liver cell necrosis but due not only to depression of cell proliferation as shown by the drop in the labelling index but also induction of apoptosis. This type of apoptosis was documented by the increase in the apoptotic index (cells labelled by TUNEL) and transglutaminase activity as well as by DNA fragmentation. The liver cells of fasted rats appeared smaller as shown by the higher cell density and DNA/protein ratio than in controls. Females were more resistant to fasting-induced apoptosis than males. A single dose of CH, a drug primary known as inhibitor of protein synthesis, induced or enhanced apoptosis in fed and 2-days fasted male rats, respectively, without any sign of cell necrosis. On the contrary, the administration of repeated doses of CH blocked apoptosis induced by fasting. CH "froze" protein and DNA content as well as apoptotic process at the level of 2 days-fasted rats. While fasting-induced liver protein loss resulted from a marked reduction in protein synthesis with a slight decrease in degradation, repeated treatment with CH virtually blocked protein loss by abolishing protein catabolism. These data suggest a direct relationship between the catabolic side of protein turnover and the apoptotic process.

Mitochondria-dependent and -independent mechanisms in tumour necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis are both regulated by interferon-gamma in human breast tumour cells.

PubMed Central

Ruiz-Ruiz, Carmen; López-Rivas, Abelardo

2002-01-01

Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL/APO-2L) induces apoptosis in a variety of tumour cells upon binding to death receptors TRAIL-R1 and TRAIL-R2. Here we describe the sensitization by interferon (IFN)-gamma to TRAIL-induced apoptosis in the breast tumour cell lines MCF-7 and MDA-MB231. IFN-gamma promoted TRAIL-mediated activation of caspase-8, Bcl-2 interacting domain death agonist (Bid) degradation, Bcl-2-associated X protein (Bax) translocation to mitochondria, cytochrome c release to the cytosol and activation of caspase-9 in these cell lines. No changes in the expression of TRAIL receptors were observed upon IFN-gamma treatment. Overexpression of Bcl-2 in MCF-7 cells completely inhibited IFN-gamma-induced sensitization to TRAIL-mediated cell death. Interestingly, TRAIL-induced apoptosis was also clearly enhanced by IFN-gamma in caspase-3-overexpressing MCF-7 cells, in the absence of Bax translocation to mitochondria and cytochrome c release to the cytosol. In summary, our results suggest that IFN-gamma facilitates TRAIL-induced activation of mitochondria-regulated as well as mitochondria-independent apoptotic pathways in breast tumour cells. PMID:11936954

Fatal serotonin toxicity caused by moclobemide and fluoxetine overdose.

PubMed

Wu, Ming-Ling; Deng, Jou-Fang

2011-01-01

Both moclobemide and fluoxetine are used in the treatment of depression, and have been shown to produce fewer side effects than conventional tricyclic antidepressants. A combination of moclobemide and fluoxetine has been used in refractory depression, however there is potential for severe serotonin toxicity. We describe a lethal case of serotonin toxicity in a 36 year-old woman after she ingested multiple drugs, including moclobemide 4500 mg, fluoxetine 200 mg, propranolol 300 mg and several benzodiazepines. The clinical features included coma, mydriasis, hyperthermia, tremor, hyperreflexia, rhabdomyolysis, renal failure and respiratory insufficiency. Eventually, the patient died of disseminated intravascular coagulation and circulatory collapse at 22.5 h postingestion. Toxicological analysis of the patient's blood confirmed high levels of moclobemide 150 μg/mL (therapeutic 1-3 μg/mL), fluoxetine 3750 ng/mL (therapeutic 47-469 ng/mL) and several benzodiazepines. In conclusion, a combination of moclobemide and fluoxetine should be avoided in depressed patients with high suicidal tendencies. Moreover, early recognition and aggressive intervention are the mainstays in the management of potentially life-threatening serotonin toxicity.

Nitric oxide is cytoprotective to breast cancer spheroids vulnerable to estrogen-induced apoptosis

PubMed Central

Shafran, Yana; Zurgil, Naomi; Ravid-Hermesh, Orit; Sobolev, Maria; Afrimzon, Elena; Hakuk, Yaron; Shainberg, Asher; Deutsch, Mordechai

2017-01-01

Estrogen-induced apoptosis has become a successful treatment for postmenopausal metastatic, estrogen receptor-positive breast cancer. Nitric oxide involvement in the response to this endocrine treatment and its influence upon estrogen receptor-positive breast cancer progression is still unclear. Nitric oxide impact on the MCF7 breast cancer line, before and after estrogen-induced apoptosis, was investigated in 3D culture systems using unique live-cell imaging methodologies. Spheroids were established from MCF7 cells vulnerable to estrogen-induced apoptosis, before and after exposure to estrogen. Spheroids derived from estrogen-treated cells exhibited extensive apoptosis levels with downregulation of estrogen receptor expression, low proliferation rate and reduced metabolic activity, unlike spheroids derived from non-treated cells. In addition to basic phenotypic differences, these two cell cluster types are diverse in their reactions to exogenous nitric oxide. A dual effect of nitric oxide was observed in the breast cancer phenotype sensitive to estrogen-induced apoptosis. Nitric oxide, at the nanomolar level, induced cell proliferation, high metabolic activity, downregulation of estrogen receptor and enhanced collective invasion, contributing to a more aggressive phenotype. Following hormone supplementation, breast cancer 3D clusters were rescued from estrogen-induced apoptosis by these low nitric oxide-donor concentrations, since nitric oxide attenuates cell death levels, upregulates survivin expression and increases metabolic activity. Higher nitric oxide concentrations (100nM) inhibited cell growth, metabolism and promoted apoptosis. These results suggest that nitric oxide, in nanomolar concentrations, may inhibit estrogen-induced apoptosis, playing a major role in hormonal therapy. Inhibiting nitric oxide activity may benefit breast cancer patients and ultimately reduce tumor recurrence. PMID:29312577

[Phloretin induces apoptosis of BEL-7402 cells in vitro].

PubMed

Luo, Hui; Wang, Ya-jun; Chen, Jie; Liu, Jiang-qin; Zhang, Hai-tao

2008-07-01

To examine the effect of phloretin on apoptosis of BEL-7402 cells. The viability changes of BEL- 7402 cells as a result of phloretin-induced toxicity were analyzed using MTT assay, and the cell morphology changes were observed with fluorescence microscope. Flow cytometry was used to analyze the cell cycle and mitochondrial membrane potential changes, and chromogenic substrate assay performed to detect caspase activity. Phloretin induced obvious cytotoxicity against BEL-7402 cells with IC50 of 89.23 microg/mL. The growth curve demonstrated decreased growth of the cells as phloretin concentration increased. Cell apoptosis occurred 24 h after treatment with 40-160 microg/mL phloretin. Morphological, the cells exposed to phloretin exhibited nuclear chromatin condensation and increased fluorescence intensity. The activity of caspase-9 reached the peak level 12 h after phloretin exposure, and leak levels of caspase-6 and caspase-3 activities occurred 18 and 24 h after the exposure, respectively. Phloretin can induce BEL-7402 cell apoptosis though the mitochondrial pathway.

Endocannabinoids participate in placental apoptosis induced by hypoxia inducible factor-1.

PubMed

Abán, C; Martinez, N; Carou, C; Albamonte, I; Toro, A; Seyahian, A; Franchi, A; Leguizamón, G; Trigubo, D; Damiano, A; Farina, M

2016-10-01

During pregnancy, apoptosis is a physiological event critical in the remodeling and aging of the placenta. Increasing evidence has pointed towards the relevance of endocannabinoids (ECs) and hypoxia as modulators of trophoblast cell death. However, the relation between these factors is still unknown. In this report, we evaluated the participation of ECs in placental apoptosis induced by cobalt chloride (CoCl2), a hypoxia mimicking agent that stabilizes the expression of hypoxia inducible factor-1 alpha (HIF-1α). We found that HIF-1α stabilization decreased FAAH mRNA and protein levels, suggesting an increase in ECs tone. Additionally, CoCl2 incubation and Met-AEA treatment reduced cell viability and increased TUNEL-positive staining in syncytiotrophoblast layer. Immunohistochemical analysis demonstrated Bax and Bcl-2 protein expression in the cytoplasm of syncytiotrophoblast. Finally, HIF-1α stabilization produced an increase in Bax/Bcl-2 ratio, activation of caspase 3 and PARP cleavage. All these changes in apoptotic parameters were reversed with AM251, a CB1 antagonist. These results demonstrate that HIF-1α may induce apoptosis in human placenta via intrinsic pathway by a mechanism that involves activation of CB1 receptor suggesting a role of the ECs in this process.

Cognitive performance of juvenile monkeys after chronic fluoxetine treatment.

PubMed

Golub, Mari S; Hackett, Edward P; Hogrefe, Casey E; Leranth, Csaba; Elsworth, John D; Roth, Robert H

2017-08-01

Potential long term effects on brain development are a concern when drugs are used to treat depression and anxiety in childhood. In this study, male juvenile rhesus monkeys (three-four years of age) were dosed with fluoxetine or vehicle (N=16/group) for two years. Histomorphometric examination of cortical dendritic spines conducted after euthanasia at one year postdosing (N=8/group) suggested a trend toward greater dendritic spine synapse density in prefrontal cortex of the fluoxetine-treated monkeys. During dosing, subjects were trained for automated cognitive testing, and evaluated with a test of sustained attention. After dosing was discontinued, sustained attention, recognition memory and cognitive flexibility were evaluated. Sustained attention was affected by fluoxetine, both during and after dosing, as indexed by omission errors. Response accuracy was not affected by fluoxetine in post-dosing recognition memory and cognitive flexibility tests, but formerly fluoxetine-treated monkeys compared to vehicle controls had more missed trial initiations and choices during testing. Drug treatment also interacted with genetic and environmental variables: MAOA genotype (high- and low transcription rate polymorphisms) and testing location (upper or lower tier of cages). Altered development of top-down cortical regulation of effortful attention may be relevant to this pattern of cognitive test performance after juvenile fluoxetine treatment. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Determination of fluoxetine in Dermestes maculatus (Coleoptera: Dermestidae) by a spectrophotometric method.

PubMed

Zanetti, Noelia I; Ferrero, Adriana A; Centeno, Néstor D

2016-12-01

The aims of this study were to detect and quantify fluoxetine, an antidepressant, from entomological samples. Larvae, pupae and adults of Dermestes maculatus (Coleoptera, Dermestidae) were reared on pig muscle previously treated with fluoxetine. The concentration selected, 2000mg/kg, emulates a fluoxetine overdose lethal to humans and laboratory animals. Thirty larvae on the fourth and fifth stages, 50 adults and several exuviae were analyzed for fluoxetine content. Detection of fluoxetine was performed by UV spectrophotometry at 270 and 277nm. All developmental stages of D. maculatus and exuviae were positive for fluoxetine. We also quantified the drug and no significant differences were found either between the days or the stages in the general model, but at 277nm a tendency of the concentration to decrease with time was observed. Concentrations of fluoxetine at 277nm were almost equal or greater than those at 270nm. This is the first study to detect and quantify fluoxetine from entomological samples and, in particular, from D. maculatus beetles. Copyright © 2016 The Chartered Society of Forensic Sciences. Published by Elsevier Ireland Ltd. All rights reserved.

Caspase-8-mediated intracellular acidification precedes mitochondrial dysfunction in somatostatin-induced apoptosis.

PubMed

Liu, D; Martino, G; Thangaraju, M; Sharma, M; Halwani, F; Shen, S H; Patel, Y C; Srikant, C B

2000-03-31

Activation of initiator and effector caspases, mitochondrial changes involving a reduction in its membrane potential and release of cytochrome c (cyt c) into the cytosol, are characteristic features of apoptosis. These changes are associated with cell acidification in some models of apoptosis. The hierarchical relationship between these events has, however, not been deciphered. We have shown that somatostatin (SST), acting via the Src homology 2 bearing tyrosine phosphatase SHP-1, exerts cytotoxic action in MCF-7 cells, and triggers cell acidification and apoptosis. We investigated the temporal sequence of apoptotic events linking caspase activation, acidification, and mitochondrial dysfunction in this system and report here that (i) SHP-1-mediated caspase-8 activation is required for SST-induced decrease in pH(i). (ii) Effector caspases are induced only when there is concomitant acidification. (iii) Decrease in pH(i) is necessary to induce reduction in mitochondrial membrane potential, cyt c release and caspase-9 activation and (iv) depletion of ATP ablates SST-induced cyt c release and caspase-9 activation, but not its ability to induce effector caspases and apoptosis. These data reveal that SHP-1-/caspase-8-mediated acidification occurs at a site other than the mitochondrion and that SST-induced apoptosis is not dependent on disruption of mitochondrial function and caspase-9 activation.

Physcion induces mitochondria-driven apoptosis in colorectal cancer cells via downregulating EMMPRIN.

PubMed

Chen, Xuehong; Gao, Hui; Han, Yantao; Ye, Junli; Xie, Jing; Wang, Chunbo

2015-10-05

Physcion, an anthraquinone derivative widely isolated and characterized from both terrestrial and marine sources, has anti-tumor effects on a variety of carcinoma cells, mainly through inhibition of cell proliferation, apoptosis induction and cell cycle arrest. However, little is known about the mechanisms underlying its role in tumor progression. In the present study, we investigated the molecular mechanisms involved in physcion-induced apoptosis in human colorectal cancer (CRC) lines HCT116. Our results showed that physcion inhibited tumor cell viability in a dose- and time-dependent manner, and induced cell apoptosis via intrinsic mitochondrial pathway. Our results also revealed that physcion treatment significantly inhibited extracelluar matrix metalloproteinase inducer (EMMPRIN) expression in HCT116 cells in a dose-dependent manner and overexpression of EMMPRIN protein markedly reduced physcion-induced cell apoptosis. Furthermore, our results strongly indicated the modulating effect of physcion on EMMPRIN is correlated with AMP-activated protein kinase (AMPK)/Hypoxia-inducible factor 1α (HIF-1α) signaling pathway. Our data provide the first experimental evidence that physcion induces mitochondrial apoptosis in CRC cells by downregulating of EMMPRIN via AMPK/HIF-1α signaling pathway and suggest a new mechanism to explain its anti-tumor effects. Copyright © 2015 Elsevier B.V. All rights reserved.

Fluoxetine exposure impacts boldness in female Siamese fighting fish, Betta splendens.

PubMed

Dzieweczynski, Teresa L; Kane, Jessica L; Campbell, Brennah A; Lavin, Lindsey E

2016-01-01

The present study examined the effects of the selective serotonin reuptake inhibitor, fluoxetine, on the behavior of female Siamese fighting fish, Betta splendens, in three different boldness assays (Empty Tank, Novel Environment, Social Tendency). When females were unexposed to fluoxetine, boldness was consistent within a context and correlated across assays. Fluoxetine exposure affected behavior within and among individuals on multiple levels. Exposure reduced overall boldness levels, made females behave in a less consistent manner, and significantly reduced correlations over time and across contexts. Fluoxetine exerted its effects on female Betta splendens behavior in a dose-dependent fashion and these effects persisted even after females were housed in clean water. If fluoxetine exposure impacts behaviors such as exploration that are necessary to an individual’s success, this may yield evolutionary consequences. In conclusion, the results show that fluoxetine exposure alters behavior beyond the level of overall response and highlights the importance of studying the behavioral effects of inadvertent pharmaceutical exposure in multiple contexts and with different dosing regimes.

Influence of gasoline inhalation on the enantioselective pharmacokinetics of fluoxetine in rats.

PubMed

Cardoso, Juciane Lauren Cavalcanti; Lanchote, Vera Lucia; Pereira, Maria Paula Marques; Capela, Jorge Manuel Vieira; Lepera, José Salvador

2013-03-01

Fluoxetine is used clinically as a racemic mixture of (+)-(S) and (-)-(R) enantiomers for the treatment of depression. CYP2D6 catalyzes the metabolism of both fluoxetine enantiomers. We aimed to evaluate whether exposure to gasoline results in CYP2D inhibition. Male Wistar rats exposed to filtered air (n = 36; control group) or to 600 ppm of gasoline (n = 36) in a nose-only inhalation exposure chamber for 6 weeks (6 h/day, 5 days/week) received a single oral 10-mg/kg dose of racemic fluoxetine. Fluoxetine enantiomers in plasma samples were analyzed by a validated analytical method using LC-MS/MS. The separation of fluoxetine enantiomers was performed in a Chirobiotic V column using as the mobile phase a mixture of ethanol:ammonium acetate 15 mM. Higher plasma concentrations of the (+)-(S)-fluoxetine enantiomer were found in the control group (enantiomeric ratio AUC((+)-(S)/(-)-(R)) = 1.68). In animals exposed to gasoline, we observed an increase in AUC(0-∞) for both enantiomers, with a sharper increase seen for the (-)-(R)-fluoxetine enantiomer (enantiomeric ratio AUC((+)-(S)/(-)-(R)) = 1.07), resulting in a loss of enantioselectivity. Exposure to gasoline was found to result in the loss of enantioselectivity of fluoxetine, with the predominant reduction occurring in the clearance of the (-)-(R)-fluoxetine enantiomer (55% vs. 30%). Copyright © 2013 Wiley Periodicals, Inc.

Ap4A induces apoptosis in human cultured cells.

PubMed

Vartanian, A; Alexandrov, I; Prudowski, I; McLennan, A; Kisselev, L

1999-07-30

Diadenosine oligophosphates (Ap(n)A) have been proposed as intracellular and extracellular signaling molecules in animal cells. The ratio of diadenosine 5',5'''-P1,P3-triphosphate to diadenosine 5',5'''-P1,P4-tetraphosphate (Ap3A/Ap4A) is sensitive to the cellular status and alters when cultured cells undergo differentiation or are treated with interferons. In cells undergoing apoptosis induced by DNA topoisomerase II inhibitor VP16, the concentration of Ap3A decreases significantly while that of Ap4A increases. Here, we have examined the effects of exogenously added Ap3A and Ap4A on apoptosis and morphological differentiation. Penetration of Ap(n)A into cells was achieved by cold shock. Ap4A at 10 microM induced programmed cell death in human HL60, U937 and Jurkat cells and mouse VMRO cells and this effect appeared to require Ap4A breakdown as hydrolysis-resistant analogues of Ap4A were inactive. On its own, Ap3A induced neither apoptosis nor cell differentiation but did display strong synergism with the protein kinase C activators 12-deoxyphorbol-13-O-phenylacetate and 12-deoxyphorbol-13-O-phenylacetate-20-acetate in inducing differentiation of HL60 cells. We propose that Ap4A and Ap3A are physiological antagonists in determination of the cellular status: Ap4A induces apoptosis whereas Ap3A is a co-inductor of differentiation. In both cases, the mechanism of signal transduction remains unknown.

Arsenic-induced alteration in intracellular calcium homeostasis induces head kidney macrophage apoptosis involving the activation of calpain-2 and ERK in Clarias batrachus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Banerjee, Chaitali; Goswami, Ramansu; Centre for Environmental Studies, Visva-Bharati University, Santiniketan 731 235

2011-10-01

We had earlier shown that exposure to arsenic (0.50 {mu}M) caused caspase-3 mediated head kidney macrophage (HKM) apoptosis involving the p38-JNK pathway in Clarias batrachus. Here we examined the roles of calcium (Ca{sup 2+}) and extra-cellular signal-regulated protein kinase (ERK), the other member of MAPK-pathway on arsenic-induced HKM apoptosis. Arsenic-induced HKM apoptosis involved increased expression of ERK and calpain-2. Nifedipine, verapamil and EGTA pre-treatment inhibited the activation of calpain-2, ERK and reduced arsenic-induced HKM apoptosis as evidenced from reduced caspase-3 activity, Annexin V-FITC-propidium iodide and Hoechst 33342 staining. Pre-incubation with ERK inhibitor U 0126 inhibited the activation of calpain-2 andmore » interfered with arsenic-induced HKM apoptosis. Additionally, pre-incubation with calpain-2 inhibitor also interfered with the activation of ERK and inhibited arsenic-induced HKM apoptosis. The NADPH oxidase inhibitor apocynin and diphenyleneiodonium chloride also inhibited ERK activation indicating activation of ERK in arsenic-exposed HKM also depends on signals from NADPH oxidase pathway. Our study demonstrates the critical role of Ca{sup 2+} homeostasis on arsenic-induced HKM apoptosis. We suggest that arsenic-induced alteration in intracellular Ca{sup 2+} levels initiates pro-apoptotic ERK and calpain-2; the two pathways influence each other positively and induce caspase-3 mediated HKM apoptosis. Besides, our study also indicates the role of ROS in the activation of ERK pathway in arsenic-induced HKM apoptosis in C. batrachus. - Highlights: > Altered Ca{sup 2+} homeostasis leads to arsenic-induced HKM apoptosis. > Calpain-2 plays a critical role in the process. > ERK is pro-apoptotic in arsenic-induced HKM apoptosis. > Arsenic-induced HKM apoptosis involves cross talk between calpain-2 and ERK.« less

CHEMOSENSITIZATION BY A NON-APOPTOGENIC HEAT SHOCK PROTEIN 70-BINDING APOPTOSIS INDUCING FACTOR MUTANT

EPA Science Inventory

Chemosensitization by a non-apoptogenic heat shock protein 70-binding apoptosis inducing factor mutant

Abstract
HSP70 inhibits apoptosis by neutralizing the caspase activator Apaf-1 and by interacting with apoptosis inducing factor (AIF), a mitochondrial flavoprotein wh...

Hydrogen peroxide-induced apoptosis in human gingival fibroblasts

PubMed Central

Gutiérrez-Venegas, Gloria; Guadarrama-Solís, Adriana; Muñoz-Seca, Carmen; Arreguín-Cano, Juan Antonio

2015-01-01

In the process of bleaching vital, discolored teeth, low concentrations of hydrogen peroxide (H2O2) are effective alternatives to heat-activated 30% H2O2. However, interest has been expressed in the assessment of pathological effects of long-term exposure to bleaching agents such as irritation and ulceration of the gingival or other soft tissues. The aim of the present study was to determine the effect of hydrogen peroxide on apoptosis in human gingival fibroblasts (HGF). Cytochrome c, Bcl-2, Bax, Bid and caspase-3 protein expression were detected by Western blotting. HGF cell apoptosis induced by H2O2 was both dose and time dependent. The addition of H2O2 resulted in the release of cytochrome c to the cytosol, and an increase of Caspase-3 cleavage. Data suggest that oxidative stress-induced apoptosis in HGF is intrinsic pathway involved the release of apoptotic signal from mitochondria. PMID:26884825

Fluoxetine (Prozac) and Pregnancy

MedlinePlus

... pregnancy complications can be related to the maternal depressive disorder itself rather than to the medication exposure. One study showed that babies whose mothers take SSRIs like fluoxetine during the second half ...

Low-power laser irradiation inhibits amyloid beta-induced cell apoptosis

NASA Astrophysics Data System (ADS)

Zhang, Heng; Wu, Shengnan

2011-03-01

The deposition and accumulation of amyloid-β-peptide (Aβ) in the brain are considered a pathological hallmark of Alzheimer's disease(AD). Apoptosis is a contributing pathophysiological mechanism of AD. Low-power laser irradiation (LPLI), a non-damage physical therapy, which has been used clinically for decades of years, is shown to promote cell proliferation and prevent apoptosis. Recently, low-power laser irradiation (LPLI) has been applied to moderate AD. In this study, Rat pheochromocytoma (PC12) cells were treated with amyloid beta 25-35 (Aβ25-35) for induction of apoptosis before LPLI treatment. We measured cell viability with CCK-8 according to the manufacture's protocol, the cell viability assays show that low fluence of LPLI (2 J/cm2 ) could inhibit the cells apoptosis. Then using statistical analysis of proportion of apoptotic cells by flow cytometry based on Annexin V-FITC/PI, the assays also reveal that low fluence of LPLI (2 J/cm2 ) could inhibit the Aβ-induced cell apoptosis. Taken together, we demonstrated that low fluence of LPLI (2 J/cm2 ) could inhibit the Aβ-induced cell apoptosis, these results directly point to a therapeutic strategy for the treatment of AD through LPLI.

Serotonergic mediation of the effects of fluoxetine, but not desipramine, in the rat forced swimming test.

PubMed

Page, M E; Detke, M J; Dalvi, A; Kirby, L G; Lucki, I

1999-11-01

The forced swimming test (FST) is a behavioral test in rodents that predicts the clinical efficacy of many types of antidepressant treatments. Recently, a behavior sampling technique was developed that scores individual response categories, including swimming, climbing and immobility. Although all antidepressant drugs reduce immobility in the FST, at least two distinct active behavioral patterns are produced by pharmacologically selective antidepressant drugs. Serotonin-selective reuptake inhibitors increase swimming behavior, while drugs acting primarily to increase extracellular levels of norepinephrine or dopamine increase climbing behavior. Distinct patterns of active behaviors in the FST may be mediated by distinct neurotransmitters, but this has not been shown directly. The present study examined the role of serotonin in mediating active behaviors in the forced swimming test after treatment with two antidepressant drugs, the selective serotonin reuptake inhibitor, fluoxetine and the selective norepinephrine reuptake inhibitor, desipramine. Endogenous serotonin was depleted by administering para-cholorophenylalanine (PCPA, 150 mg/kg, IP.) to rats 72 h and 48 h prior to the swim test. Fluoxetine (10 mg/kg, SC) or desipramine (10 mg/kg, SC) was given three times over a 24-h period prior to the FST. Behavioral responses, including immobility, swimming and climbing, were counted during the 5-min test. Pretreatment with PCPA blocked fluoxetine-induced reduction in immobility and increase in swimming behavior during the FST. In contrast, PCPA pretreatment did not interfere with the ability of desipramine to reduce immobility and increase climbing behavior. Depletion of serotonin prevented the behavioral effects of the selective serotonin reuptake inhibitor fluoxetine in the rat FST. Furthermore, depletion of serotonin had no impact on the behavioral effects induced by the selective norepinephrine reuptake inhibitor, desipramine. The effects of antidepressant drugs

Cathepsin B is involved in the heat shock induced cardiomyocytes apoptosis as well as the anti-apoptosis effect of HSP-70.

PubMed

Hsu, Shu-Fen; Hsu, Chuan-Chih; Cheng, Bor-Chih; Lin, Cheng-Hsien

2014-11-01

Cathepsin B is one of the major lysosomal cysteine proteases that plays an important role in apoptosis. Herein, we investigated whether Cathepsin B is involved in cardiomyocyte apoptosis caused by hyperthermic injury (HI) and heat shock protein (HSP)-70 protects these cells from HI-induced apoptosis mediated by Cathepsin. HI was produced in H9C2 cells by putting them in a circulating 43 °C water bath for 120 min, whereas preinduction of HSP-70 was produced in H9C2 cells by mild heat preconditioning (or putting them in 42 °C water bath for 30 min) 8 h before the start of HI. It was found that HI caused both cardiomyocyte apoptosis and increased Cathepsin B activity in H9C2 cells. E-64-c, in addition to reducing Cathepsin B activity, significantly attenuated HI-induced cardiomyocyte apoptosis (evidenced by increased apoptotic cell numbers, increased tuncated Bid (t-Bid), increased cytochrome C, increased caspase-9/-3, and decreased Bcl-2/Bax) in H9C2 cells. In addition, preinduction of HSP-70 by mild heat preconditioning or inhibition of HSP-70 by Tripolide significantly attenuated or exacerbated respectively both the cardiomyocyte apoptosis and increased Cathepsin B activity in H9C2 cells. Furthermore, the beneficial effects of pre-induction of HSP-70 by mild heat production in reducing both cardiomyocyte apoptosis and increased Cathepsin B activity caused by HI can be significantly reduced by Triptolide preconditioning. These results indicate that Cathepsin B is involved in HI-induced cardiomyocyte apoptosis in H9C2 cells and HSP-70 protects these cells from HI-induced cardiomyocyte apoptosis through Cathepsin B pathways.

Paroxetine and fluoxetine in pregnancy: a prospective, multicentre, controlled, observational study

PubMed Central

Diav-Citrin, Orna; Shechtman, Svetlana; Weinbaum, Dafna; Wajnberg, Rebecka; Avgil, Meytal; Di Gianantonio, Elena; Clementi, Maurizio; Weber-Schoendorfer, Corinna; Schaefer, Christof; Ornoy, Asher

2008-01-01

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT In recent years there has been concern regarding the possibility that selective serotonin reuptake inhibitors (SSRIs) cause an increased rate of congenital cardiovascular anomalies. As of today, there is still debate in the literature as to the possible effects of paroxetine and fluoxetine on the embryonic cardiovascular system. WHAT THIS STUDY ADDS Based on prospective data from three Teratogen Information Services, we have demonstrated an increased rate of congenital cardiovascular anomalies among the offspring of fluoxetine- and paroxetine-treated mothers. AIMS Recent studies have suggested a possible association between maternal use of selective serotonin reuptake inhibitors (SSRIs) in early pregnancy and cardiovascular anomalies. The aim of the present study was to evaluate the teratogenic risk of paroxetine and fluoxetine. METHODS This multicentre, prospective, controlled study evaluated the rate of major congenital anomalies after first-trimester gestational exposure to paroxetine, fluoxetine or nonteratogens. RESULTS We followed up 410 paroxetine, 314 fluoxetine first-trimester exposed pregnancies and 1467 controls. After exclusion of genetic and cytogenetic anomalies, there was a higher rate of major anomalies in the SSRI groups compared with the controls [paroxetine 18/348 (5.2%), fluoxetine 12/253 (4.7%) and controls 34/1359 (2.5%)]. The main risk applied to cardiovascular anomalies [paroxetine 7/348 (2.0%), crude odds ratio (OR) 3.47, 95% confidence interval (CI) 1.13, 10.58; fluoxetine 7/253 (2.8%), crude OR, 4.81 95% CI 1.56, 14.71; and controls 8/1359 (0.6%)]. On logistic regression analysis only cigarette smoking of ≥10 cigarettes day−1 and fluoxetine exposure were significant variables for cardiovascular anomalies. The adjusted ORs for paroxetine and fluoxetine were 2.66 (95% CI 0.80, 8.90) and 4.47 (95% CI 1.31, 15.27), respectively. CONCLUSION This study suggests a possible association between

Albumin-induced apoptosis of tubular cells is modulated by BASP1

PubMed Central

Sanchez-Niño, M D; Fernandez-Fernandez, B; Perez-Gomez, M V; Poveda, J; Sanz, A B; Cannata-Ortiz, P; Ruiz-Ortega, M; Egido, J; Selgas, R; Ortiz, A

2015-01-01

Albuminuria promotes tubular injury and cell death, and is associated with faster progression of chronic kidney disease (CKD) to end-stage renal disease. However, the molecular mechanisms regulating tubular cell death in response to albuminuria are not fully understood. Brain abundant signal protein 1 (BASP1) was recently shown to mediate glucose-induced apoptosis in tubular cells. We have studied the role of BASP1 in albumin-induced tubular cell death. BASP1 expression was studied in experimental puromycin aminonucleoside-induced nephrotic syndrome in rats and in human nephrotic syndrome. The role of BASP1 in albumin-induced apoptosis was studied in cultured human HK2 proximal tubular epithelial cells. Puromycin aminonucleoside induced proteinuria and increased total kidney BASP1 mRNA and protein expression. Immunohistochemistry localized the increased BASP1 to tubular cells. BASP1 expression colocalized with deoxynucleotidyl-transferase-mediated dUTP nick-end labeling staining for apoptotic cells. Increased tubular BASP1 expression was observed in human proteinuric nephropathy by immunohistochemistry, providing evidence for potential clinical relevance. In cultured tubular cells, albumin induced apoptosis and increased BASP1 mRNA and protein expression at 6–48 h. Confocal microscopy localized the increased BASP1 expression in albumin-treated cells mainly to the perinuclear area. A peripheral location near the cell membrane was more conspicuous in albumin-treated apoptotic cells, where it colocalized with actin. Inhibition of BASP1 expression by a BASP1 siRNA protected from albumin-induced apoptosis. In conclusion, albumin-induced apoptosis in tubular cells is BASP1-dependent. This information may be used to design novel therapeutic approaches to slow CKD progression based on protection of tubular cells from the adverse consequences of albuminuria. PMID:25675304

Autophagy regulates chlorpyrifos-induced apoptosis in SH-SY5Y cells.

PubMed

Park, Jae Hyeon; Lee, Jeong Eun; Shin, In Chul; Koh, Hyun Chul

2013-04-01

Recent studies have shown that up-regulation of autophagy may be a tractable therapeutic intervention for clearing disease-causing proteins, including α-synuclein, ubiquitin, and other misfolded or aggregated proteins in pesticide-induced neurodegeneration. In a previous study, we reported that chlorpyrifos (CPF)-induced mitochondria-dependent apoptosis is mediated through reactive oxygen species in SH-SY5Y cells. In this study, we explored a novel pharmacotherapeutic approach to prevent CPF neurotoxicity involving the regulation of autophagy. We investigated the modulation of CPF-induced apoptosis according to autophagy regulation. We found that CPF induced apoptosis in SH-SY5Y cells, as demonstrated by the activation of caspase-3 and nuclear condensation. In addition, we observed that cells treated with CPF underwent autophagic cell death by monitoring the expression of LC3-II and p62. Pretreatment with the autophagy inducer rapamycin significantly enhanced the cell viability of CPF-exposed cells, and the enhancement of cell viability was partially due to alleviation of CPF-induced apoptosis via a decrease in levels of cleaved caspase-3. Specifically, rapamycin pretreatment decreased Bax and increased Bcl-2 expression in mitochondria. In addition, rapamycin significantly decreased cytochrome c release in from mitochondria into the cytosol. However, pretreatment of cells with the autophagy inhibitor, 3-methyladenine (3MA), remarkably increased CPF toxicity in these cells; this with correlated with increased expression of Bax and decreased expression of Bcl-2 in mitochondria. Our results suggest that CPF-induced cytotoxicity is modified by autophagy regulation and that rapamycin protects against CPF-induced apoptosis by enhancing autophagy. Pharmacologic induction of autophagy by rapamycin may be a useful treatment strategy in neurodegenerative disorders. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

Curcumin Induces Apoptosis of Upper Aerodigestive Tract Cancer Cells by Targeting Multiple Pathways

PubMed Central

Amin, A. R. M. Ruhul; Haque, Abedul; Rahman, Mohammad Aminur; Chen, Zhuo Georgia; Khuri, Fadlo Raja; Shin, Dong Moon

2015-01-01

Curcumin, a natural compound isolated from the Indian spice "Haldi" or "curry powder", has been used for centuries as a traditional remedy for many ailments. Recently, the potential use of curcumin in cancer prevention and therapy urges studies to uncover the molecular mechanisms associated with its anti-tumor effects. In the current manuscript, we investigated the mechanism of curcumin-induced apoptosis in upper aerodigestive tract cancer cell lines and showed that curcumin-induced apoptosis is mediated by the modulation of multiple pathways such as induction of p73, and inhibition of p-AKT and Bcl-2. Treatment of cells with curcumin induced both p53 and the related protein p73 in head and neck and lung cancer cell lines. Inactivation of p73 by dominant negative p73 significantly protected cells from curcumin-induced apoptosis, whereas ablation of p53 by shRNA had no effect. Curcumin treatment also strongly inhibited p-AKT and Bcl-2 and overexpression of constitutively active AKT or Bcl-2 significantly inhibited curcumin-induced apoptosis. Taken together, our findings suggest that curcumin-induced apoptosis is mediated via activating tumor suppressor p73 and inhibiting p-AKT and Bcl-2. PMID:25910231

Antiproliferative and apoptosis inducing effects of citral via p53 and ROS-induced mitochondrial-mediated apoptosis in human colorectal HCT116 and HT29 cell lines.

PubMed

Sheikh, Bassem Y; Sarker, Md Moklesur Rahman; Kamarudin, Muhamad Noor Alfarizal; Mohan, Gokula

2017-12-01

Despite various anticancer reports, antiproliferative and apoptosis inducing activity of citral in HCT116 and HT29 cells have never been reported. This study aimed to evaluate the cytotoxic and apoptosis inducing effects of citral in colorectal cancer cell lines. The citral-treated cells were subjected to MTT assay followed by flow cytometric Annexin V-FITC/PI, mitochondrial membrane potential and intracellular reactive oxygen species (ROS) determination. The apoptotic proteins expression was investigated by Western blot analysis. Citral inhibited the growth of HCT116 and HT29 cells by dose- and time-dependent manner without inducing cytotoxicity in CCD841-CoN normal colon cells. Flow cytometric analysis showed that citral (50-200μM; 24-48h) induced the externalization of phoshpotidylserine and reduced the mitochondrial membrane potential in HCT116 and HT29 cells. Citral elevated intracellular ROS level while attenuating GSH levels in HCT116 and HT29 cells which were reversed with N-acetycysteine (2mM) pre-treatment indicating that citral induced mitochondrial-mediated apoptosis via augmentation of intracellular ROS. Citral induced the phosphorylation of p53 protein and the expression of Bax while decreasing Bc-2 and Bcl-xL expression which promoted the cleavage of caspase-3. Collectively, our data suggest that citral induced p53 and ROS-mediated mitochondrial-mediated apoptosis in human colorectal cancer HCT116 and HT29 cells. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

High glucose induces apoptosis via upregulation of Bim expression in proximal tubule epithelial cells.

PubMed

Zhang, Xiao-Qian; Dong, Jian-Jun; Cai, Tian; Shen, Xue; Zhou, Xiao-Jun; Liao, Lin

2017-04-11

Diabetic nephropathy is the primary cause of end-stage renal disease. Apoptosis of tubule epithelial cells is a major feature of diabetic nephropathy. The mechanisms of high glucose (HG) induced apoptosis are not fully understood. Here we demonstrated that, HG induced apoptosis via upregulating the expression of proapoptotic Bcl-2 homology domain 3 (BH3)-only protein Bim protein, but not bring a significant change in the baseline level of autophagy in HK2 cells. The increase of Bim expression was caused by the ugregulation of transcription factors, FOXO1 and FOXO3a. Bim expression initiates BAX/BAK-mediated mitochondria-dependent apoptosis. Silence of Bim by siRNA in HK2 cells prevented HG-induced apoptosis and also sensitized HK2 cells to autophagy during HG treatment. The autophagy inhibitor 3-MA increased the injury in Bim knockdown HK2 cells by retriggering apoptosis. The above results suggest a Bim-independent apoptosis pathway in HK2 cells, which normally could be inhibited by autophagy. Overall, our results indicate that HG induces apoptosis via up-regulation of Bim expression in proximal tubule epithelial cells.

Fluoxetine Decreases the Proliferation and Adipogenic Differentiation of Human Adipose-Derived Stem Cells

PubMed Central

Sun, Bo Kyung; Kim, Ji Hye; Choi, Joon-Seok; Hwang, Sung-Joo; Sung, Jong-Hyuk

2015-01-01

Fluoxetine was originally developed as an antidepressant, but it has also been used to treat obesity. Although the anti-appetite effect of fluoxetine is well-documented, its potential effects on human adipose-derived stem cells (ASCs) or mature adipocytes have not been investigated. Therefore, we investigated the mechanisms underlying the inhibitory effects of fluoxetine on the proliferation of ASCs. We also investigated its inhibitory effect on adipogenic differentiation. Fluoxetine significantly decreased ASC proliferation, and signal transduction PCR array analysis showed that it increased expression of autophagy-related genes. In addition, fluoxetine up-regulated SQSTM1 and LC3B protein expression as detected by western blotting and immunofluorescence. The autophagy inhibitor, 3-methyladenine (3-MA), significantly attenuated fluoxetine-mediated effects on ASC proliferation and SQSTM1/LC3B expression. In addition, 3-MA decreased the mRNA expression of two autophagy-related genes, beclin-1 and Atg7, in ASCs. Fluoxetine also significantly inhibited lipid accumulation and down-regulated the levels of PPAR-γ and C/EBP-α in ASCs. Collectively, these results indicate that fluoxetine decreases ASC proliferation and adipogenic differentiation. This is the first in vitro evidence that fluoxetine can reduce fat accumulation by inhibiting ASC proliferation and differentiation. PMID:26204837

Fluoxetine Decreases the Proliferation and Adipogenic Differentiation of Human Adipose-Derived Stem Cells.

PubMed

Sun, Bo Kyung; Kim, Ji Hye; Choi, Joon-Seok; Hwang, Sung-Joo; Sung, Jong-Hyuk

2015-07-22

Fluoxetine was originally developed as an antidepressant, but it has also been used to treat obesity. Although the anti-appetite effect of fluoxetine is well-documented, its potential effects on human adipose-derived stem cells (ASCs) or mature adipocytes have not been investigated. Therefore, we investigated the mechanisms underlying the inhibitory effects of fluoxetine on the proliferation of ASCs. We also investigated its inhibitory effect on adipogenic differentiation. Fluoxetine significantly decreased ASC proliferation, and signal transduction PCR array analysis showed that it increased expression of autophagy-related genes. In addition, fluoxetine up-regulated SQSTM1 and LC3B protein expression as detected by western blotting and immunofluorescence. The autophagy inhibitor, 3-methyladenine (3-MA), significantly attenuated fluoxetine-mediated effects on ASC proliferation and SQSTM1/LC3B expression. In addition, 3-MA decreased the mRNA expression of two autophagy-related genes, beclin-1 and Atg7, in ASCs. Fluoxetine also significantly inhibited lipid accumulation and down-regulated the levels of PPAR-γ and C/EBP-α in ASCs. Collectively, these results indicate that fluoxetine decreases ASC proliferation and adipogenic differentiation. This is the first in vitro evidence that fluoxetine can reduce fat accumulation by inhibiting ASC proliferation and differentiation.

Phosphorylation status modulates Bcl-2 function during glucocorticoid-induced apoptosis in T lymphocytes.

PubMed

Huang, Se-Te J; Cidlowski, John A

2002-06-01

Glucocorticoids are known to induce apoptosis in lymphoid cells, and Bcl-2 overexpression can block the apoptosis-inducing action of glucocorticoids. Since phosphorylation of Bcl-2 is implicated in regulating Bcl-2 function, we considered the role of Bcl-2 phosphorylation in protecting lymphoid cells from glucocorticoid-induced cell death. Five stably transfected cell lines of WEHI 7.1 cells expressing either wild-type Bcl-2 or alanine mutants of Bcl-2 at amino acids threonine 56, serine 70, threonine 74, or serine 87 were created. Expression of the mutant Bcl-2 proteins was documented by flow cytometry and Western blot analysis. Mutation of Bcl-2 on T56 and S87 eliminated the ability of Bcl-2 to inhibit glucocorticoid-induced cell shrinkage, mitochondrial depolarization, DNA fragmentation, and cell death. Mutation of T74 only partially impaired the ability of Bcl-2 to block glucocorticoid-induced apoptosis whereas mutation of S70 in Bcl-2 did not alter its ability to block glucocorticoid-induced apoptosis.

Plasmodium falciparum, but not P. vivax, can induce erythrocytic apoptosis.

PubMed

Totino, Paulo Renato Rivas; Magalhães, Aline das Dores; Alves, Eliana Brasil; Costa, Monica Regina Farias; de Lacerda, Marcus Vinícius Guimarães; Daniel-Ribeiro, Cláudio Tadeu; Ferreira-da-Cruz, Maria de Fátima

2014-10-18

Apoptosis can occur in red blood cells (RBC) and seems to be involved in hematologic disorders related to many diseases. In malaria it is known that parasitized RBC (pRBC) is involved in the development of anemia and thrombosis; however, non-parasitized RBC (nRBC) apoptosis could amplify these malaria-associated hematologic events. In fact, in experimental malaria, increased levels of apoptosis were observed in nRBC during lethal Plasmodium yoelii 17XL infection, but in human malaria erythrocytic apoptosis has never been studied. The present study was performed to investigate if nRBC apoptosis also occurs in P. vivax and P. falciparum infections. Apoptosis of nRBC was evaluated in blood samples of P. vivax malaria patients and clinically healthly individuals living in Manaus, Brazil, both ex vivo and after incubation of RBC for 24 h. Additionally, the capacity of plasma from P. vivax or P. falciparum patients was tested for induction of in vitro apoptosis of normal RBC from a clinically healthy individual living in a non-endemic malaria region. Apoptosis was detected by flow cytometry using annexin V staining. In contrast to experimental malaria that significantly increased the levels of apoptotic nRBC both ex-vivo and after 24 h of incubation, no significant alteration on apoptotic nRBC rates was detected in P. vivax infected patients when compared with non-infected control individuals. Similar results were observed when plasma of these P. vivax patients was incubated with normal RBC. Conversely, plasma from P. falciparum-infected subjects induced significant apoptosis of these cells. Apoptosis of normal RBC can be induced by plasma from individuals with P. falciparum (but not with P. vivax) malaria. This finding could reflect the existence of erythrocytic apoptosis during infection that could contribute to the pathogenesis of hematological and vascular complications associated with falciparum malaria.

Apoptosis of vascular smooth muscle cells induces features of plaque vulnerability in atherosclerosis.

PubMed

Clarke, Murray C H; Figg, Nichola; Maguire, Janet J; Davenport, Anthony P; Goddard, Martin; Littlewood, Trevor D; Bennett, Martin R

2006-09-01

Vascular smooth muscle cell (VSMC) apoptosis occurs in many arterial diseases, including aneurysm formation, angioplasty restenosis and atherosclerosis. Although VSMC apoptosis promotes vessel remodeling, coagulation and inflammation, its precise contribution to these diseases is unknown, given that apoptosis frequently accompanies vessel injury or alterations to flow. To study the direct consequences of VSMC apoptosis, we generated transgenic mice expressing the human diphtheria toxin receptor (hDTR, encoded by HBEGF) from a minimal Tagln (also known as SM22alpha) promoter. Despite apoptosis inducing loss of 50-70% of VSMCs, normal arteries showed no inflammation, reactive proliferation, thrombosis, remodeling or aneurysm formation. In contrast, VSMC apoptosis in atherosclerotic plaques of SM22alpha-hDTR Apoe-/- mice induced marked thinning of fibrous cap, loss of collagen and matrix, accumulation of cell debris and intense intimal inflammation. We conclude that VSMC apoptosis is 'silent' in normal arteries, which have a large capacity to withstand cell loss. In contrast, VSMC apoptosis alone is sufficient to induce features of plaque vulnerability in atherosclerosis. SM22alpha-hDTR Apoe-/- mice may represent an important new model to test agents proposed to stabilize atherosclerotic plaques.

Human Embryonic and Induced Pluripotent Stem Cells Express TRAIL Receptors and Can Be Sensitized to TRAIL-Induced Apoptosis

PubMed Central

Vinarsky, Vladimir; Krivanek, Jan; Rankel, Liina; Nahacka, Zuzana; Barta, Tomas; Jaros, Josef; Andera, Ladislav

2013-01-01

Death ligands and their tumor necrosis factor receptor (TNFR) family receptors are the best-characterized and most efficient inducers of apoptotic signaling in somatic cells. In this study, we analyzed whether these prototypic activators of apoptosis are also expressed and able to be activated in human pluripotent stem cells. We examined human embryonic stem cells (hESC) and human-induced pluripotent stem cells (hiPSC) and found that both cell types express primarily TNF-related apoptosis-inducing ligand (TRAIL) receptors and TNFR1, but very low levels of Fas/CD95. We also found that although hESC and hiPSC contain all the proteins required for efficient induction and progression of extrinsic apoptotic signaling, they are resistant to TRAIL-induced apoptosis. However, both hESC and hiPSC can be sensitized to TRAIL-induced apoptosis by co-treatment with protein synthesis inhibitors such as the anti-leukemia drug homoharringtonine (HHT). HHT treatment led to suppression of cellular FLICE inhibitory protein (cFLIP) and Mcl-1 expression and, in combination with TRAIL, enhanced processing of caspase-8 and full activation of caspase-3. cFLIP likely represents an important regulatory node, as its shRNA-mediated down-regulation significantly sensitized hESC to TRAIL-induced apoptosis. Thus, we provide the first evidence that, irrespective of their origin, human pluripotent stem cells express canonical components of the extrinsic apoptotic system and on stress can activate death receptor-mediated apoptosis. PMID:23806100

Synthesis of sphingosine is essential for oxidative stress-induced apoptosis of photoreceptors.

PubMed

Abrahan, Carolina E; Miranda, Gisela E; Agnolazza, Daniela L; Politi, Luis E; Rotstein, Nora P

2010-02-01

Oxidative stress is involved in inducing apoptosis of photoreceptors in many retinal neurodegenerative diseases. It has been shown that oxidative stress increases in photoreceptors the synthesis of ceramide, a sphingolipid precursor that then activates apoptosis. In several cell types, ceramide is converted by ceramidases to sphingosine (Sph), another apoptosis mediator; hence, this study was undertaken to determine whether Sph participates in triggering photoreceptor apoptosis. Rat retina neurons were incubated with [(3)H]palmitic acid and treated with the oxidant paraquat (PQ) to evaluate Sph synthesis. Sph was added to cultures with or without docosahexaenoic acid (DHA), the major retina polyunsaturated fatty acid and a photoreceptor survival factor, to evaluate apoptosis. Synthesis of Sph and sphingosine-1-phosphate (S1P), a prosurvival signal, were inhibited with alkaline ceramidase or sphingosine kinase inhibitors, respectively, before adding PQ, C(2)-ceramide, or Sph. Apoptosis, mitochondrial membrane polarization, cytochrome c localization, and reactive oxygen species (ROS) production were determined. PQ increased [(3)H]Sph synthesis in photoreceptors and blocking this synthesis by inhibiting alkaline ceramidase decreased PQ-induced apoptosis. Addition of Sph induced photoreceptor apoptosis, increased ROS production, and promoted cytochrome c release from mitochondria. Although DHA prevented this apoptosis, inhibiting Sph conversion to S1P blocked DHA protection. These results suggest that oxidative stress enhances formation of ceramide and its subsequent breakdown to Sph; ceramide and/or Sph would then trigger photoreceptor apoptosis. Preventing Sph synthesis or promoting its phosphorylation to S1P rescued photoreceptors, suggesting that Sph is a mediator of their apoptosis and modulation of Sph metabolism may be crucial for promoting photoreceptor survival.

Lipocalin-2 Induces Cardiomyocyte Apoptosis by Increasing Intracellular Iron Accumulation*

PubMed Central

Xu, Guoxiong; Ahn, JinHee; Chang, SoYoung; Eguchi, Megumi; Ogier, Arnaud; Han, SungJun; Park, YoungSam; Shim, ChiYoung; Jang, YangSoo; Yang, Bo; Xu, Aimin; Wang, Yu; Sweeney, Gary

2012-01-01

Our objective was to determine whether lipocalin-2 (Lcn2) regulates cardiomyocyte apoptosis, the mechanisms involved, and the functional significance. Emerging evidence suggests that Lcn2 is a proinflammatory adipokine associated with insulin resistance and obesity-related complications, such as heart failure. Here, we used both primary neonatal rat cardiomyocytes and H9c2 cells and demonstrated for the first time that Lcn2 directly induced cardiomyocyte apoptosis, an important component of cardiac remodeling leading to heart failure. This was shown by detection of DNA fragmentation using TUNEL assay, phosphatidylserine exposure using flow cytometry to detect annexin V-positive cells, caspase-3 activity using enzymatic assay and immunofluorescence, and Western blotting for the detection of cleaved caspase-3. We also observed that Lcn2 caused translocation of the proapoptotic protein Bax to mitochondria and disruption of mitochondrial membrane potential. Using transient transfection of GFP-Bax, we confirmed that Lcn2 induced co-localization of Bax with MitoTracker® dye. Importantly, we used the fluorescent probe Phen Green SK to demonstrate an increase in intracellular iron in response to Lcn2, and depleting intracellular iron using an iron chelator prevented Lcn2-induced cardiomyocyte apoptosis. Administration of recombinant Lcn2 to mice for 14 days increased cardiomyocyte apoptosis as well as an acute inflammatory response with compensatory changes in cardiac functional parameters. In conclusion, Lcn2-induced cardiomyocyte apoptosis is of physiological significance and occurs via a mechanism involving elevated intracellular iron levels and Bax translocation. PMID:22117066

Mycobacterium avium MAV2052 protein induces apoptosis in murine macrophage cells through Toll-like receptor 4.

PubMed

Lee, Kang-In; Choi, Han-Gyu; Son, Yeo-Jin; Whang, Jake; Kim, Kwangwook; Jeon, Heat Sal; Park, Hye-Soo; Back, Yong Woo; Choi, Seunga; Kim, Seong-Woo; Choi, Chul Hee; Kim, Hwa-Jung

2016-04-01

Mycobacterium avium and its sonic extracts induce apoptosis in macrophages. However, little is known about the M. avium components regulating macrophage apoptosis. In this study, using multidimensional fractionation, we identified MAV2052 protein, which induced macrophage apoptosis in M. avium culture filtrates. The recombinant MAV2052 induced macrophage apoptosis in a caspase-dependent manner. The loss of mitochondrial transmembrane potential (ΔΨm), mitochondrial translocation of Bax, and release of cytochrome c from mitochondria were observed in macrophages treated with MAV2052. Further, reactive oxygen species (ROS) production was required for the apoptosis induced by MAV2052. In addition, ROS and mitogen-activated protein kinases were involved in MAV2052-mediated TNF-α and IL-6 production. ROS-mediated activation of apoptosis signal-regulating kinase 1 (ASK1)-JNK pathway was a major signaling pathway for MAV2052-induced apoptosis. Moreover, MAV2052 bound to Toll-like receptor (TLR) 4 molecule and MAV2052-induced ROS production, ΔΨm loss, and apoptosis were all significantly reduced in TLR4(-/-) macrophages. Altogether, our results suggest that MAV2052 induces apoptotic cell death through TLR4 dependent ROS production and JNK pathway in murine macrophages.

FLUOXETINE INHIBITS OSTEOBLAST DIFFERENTIATION & MINERALIZATION IN FRACTURE HEALING

PubMed Central

Bradaschia-Correa, Vivian; Josephson, Anne M; Mehta, Devan; Mizrahi, Matthew; Neibart, Shane S; Liu, Chao; Kennedy, Oran; Castillo, Alesha B; Egol, Kenneth A; Leucht, Philipp

2016-01-01

Chronic use of selective serotonin reuptake inhibitors (SSRIs) for the treatment of depression has been linked to osteoporosis. In this study, we investigated the effect of chronic SSRI use on fracture healing in two murine models of bone regeneration. First, we performed a comprehensive analysis of endochondral bone healing in a femur fracture model. C57/BL6 mice treated with fluoxetine, the most commonly prescribed SSRI, developed a normal cartilaginous soft-callus at 14 days after fracture and demonstrated a significantly smaller and biomechanically weaker bony hard-callus at 28 days. In order to further dissect the mechanism that resulted in a smaller bony regenerate, we used an intramembranous model of bone healing and revealed that fluoxetine treatment resulted in a significantly smaller bony callus at 7 and 14 days postinjury. In order to test whether the smaller bony regenerate following fluoxetine treatment was caused by an inhibition of osteogenic differentiation and/or mineralization, we employed in vitro experiments, which established that fluoxetine treatment decreases osteogenic differentiation and mineralization and that this effect is serotonin-independent. Finally, in a translational approach, we tested whether cessation of the medication would result in restoration of the regenerative potential. However, histologic and µCT analysis revealed non-union formation in these animals with fibrous tissue interposition within the callus. In conclusion, fluoxetine exerts a direct, inhibitory effect on osteoblast differentiation and mineralization, shown in two disparate murine models of bone repair. Discontinuation of the drug did not result in restoration of the healing potential, but rather led to complete arrest of the repair process. Besides the well-established effect of SSRIs on bone homeostasis, our study provides strong evidence that fluoxetine use negatively impacts fracture healing. PMID:27869327

Gonadal steroids modulate Fas-induced apoptosis of lactotropes and somatotropes.

PubMed

Jaita, Gabriela; Zárate, Sandra; Ferrari, Luciana; Radl, Daniela; Ferraris, Jimena; Eijo, Guadalupe; Zaldivar, Verónica; Pisera, Daniel; Seilicovich, Adriana

2011-02-01

We have previously reported that Fas activation induces apoptosis of anterior pituitary cells from rats at proestrus but not at diestrus and in an estrogen-dependent manner. In this study, we evaluated the effect of Fas activation on apoptosis of lactotropes and somatotropes during the estrous cycle and explored the action of gonadal steroids on Fas-induced apoptosis. Also, we studied whether changes in Fas expression are involved in the apoptotic response of anterior pituitary cells. Fas activation increased the percentage of TUNEL-positive lactotropes and somatotropes at proestrus but not at diestrus. FasL triggered apoptosis of somatotropes only when cells from ovariectomized rats were cultured in the presence of 17 β-estradiol (E2). Progesterone (P4) blocked the apoptotic action of the Fas/FasL system in lactotropes and somatotropes incubated with E2. Both E2 and P4 increased the percentage of cells expressing Fas at the cell membrane. Our results show that Fas activation induces apoptosis of lactotropes and somatotropes at proestrus but not at diestrus. Gonadal steroids may be involved in the apoptotic response of lactotropes and somatotropes, suggesting that Fas activation is implicated in the renewal of these pituitary subpopulations during the estrous cycle. The effect of gonadal steroids on Fas expression may be only partially involved in regulation of the Fas/FasL apoptotic pathway in the anterior pituitary gland.

Lentiviral Delivery of HIV-1 Vpr Protein Induces Apoptosis in Transformed Cells

NASA Astrophysics Data System (ADS)

Stewart, Sheila A.; Poon, Betty; Jowett, Jeremy B. M.; Xie, Yiming; Chen, Irvin S. Y.

1999-10-01

Most current anticancer therapies act by inducing tumor cell stasis followed by apoptosis. HIV-1 Vpr effectively induces apoptosis of T cells after arrest of cells at a G2/M checkpoint. Here, we investigated whether this property of Vpr could be exploited for use as a potential anticancer agent. As a potentially safer alternative to transfer of genes encoding Vpr, we developed a method to efficiently introduce Vpr protein directly into cells. Vpr packaged into HIV-1 virions lacking a genome induced efficient cell cycle arrest and apoptosis. Introduction of Vpr into tumor cell lines of various tissue origin, including those bearing predisposing mutations in p53, XPA, and hMLH1, induced cell cycle arrest and apoptosis with high efficiency. Significantly, apoptosis mediated by virion-associated Vpr was more effective on rapidly dividing cells compared with slow-growing cells, thus, in concept, providing a potential differential effect between some types of tumor cells and surrounding normal cells. This model system provides a rationale and proof of concept for the development of potential cancer therapeutic agents based on the growth-arresting and apoptotic properties of Vpr.

Clinostat rotation induces apoptosis in luteal cells of the pregnant rat

NASA Technical Reports Server (NTRS)

Yang, Hyunwon; Bhat, Ganapathy K.; Sridaran, Rajagopala

2002-01-01

Recent studies have shown that microgravity induces changes at the cellular level, including apoptosis. However, it is unknown whether microgravity affects luteal cell function. This study was performed to assess whether microgravity conditions generated by clinostat rotation induce apoptosis and affect steroidogenesis by luteal cells. Luteal cells isolated from the corpora lutea of Day 8 pregnant rats were placed in equal numbers in slide flasks (chamber slides). One slide flask was placed in the clinostat and the other served as a stationary control. At 48 h in the clinostat, whereas the levels of progesterone and total cellular protein decreased, the number of shrunken cells increased. To determine whether apoptosis occurred in shrunken cells, Comet and TUNEL assays were performed. At 48 h, the percentage of apoptotic cells in the clinostat increased compared with that in the control. To investigate how the microgravity conditions induce apoptosis, the active mitochondria in luteal cells were detected with JC-1 dye. Cells in the control consisted of many active mitochondria, which were evenly distributed throughout the cell. In contrast, cells in the clinostat displayed fewer active mitochondria, which were distributed either to the outer edge of the cell or around the nucleus. These results suggest that mitochondrial dysfunction induced by clinostat rotation could lead to apoptosis in luteal cells and suppression of progesterone production.

Radiation-Induced Salivary Gland Dysfunction Results From p53-Dependent Apoptosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Avila, Jennifer L.; Grundmann, Oliver; Burd, Randy

2009-02-01

Purpose: Radiotherapy for head-and-neck cancer causes adverse secondary side effects in the salivary glands and results in diminished quality of life for the patient. A previous in vivo study in parotid salivary glands demonstrated that targeted head-and-neck irradiation resulted in marked increases in phosphorylated p53 (serine{sup 18}) and apoptosis, which was suppressed in transgenic mice expressing a constitutively active mutant of Akt1 (myr-Akt1). Methods and Materials: Transgenic and knockout mouse models were exposed to irradiation, and p53-mediated transcription, apoptosis, and salivary gland dysfunction were analyzed. Results: The proapoptotic p53 target genes PUMA and Bax were induced in parotid salivary glandsmore » of mice at early time points after therapeutic radiation. This dose-dependent induction requires expression of p53 because no radiation-induced expression of PUMA and Bax was observed in p53-/- mice. Radiation also induced apoptosis in the parotid gland in a dose-dependent manner, which was p53 dependent. Furthermore, expression of p53 was required for the acute and chronic loss of salivary function after irradiation. In contrast, apoptosis was not induced in p53-/- mice, and their salivary function was preserved after radiation exposure. Conclusions: Apoptosis in the salivary glands after therapeutic head-and-neck irradiation is mediated by p53 and corresponds to salivary gland dysfunction in vivo.« less

Resistance to etoposide-induced apoptosis in a Burkitt's lymphoma cell line.

PubMed

Zhao, E G; Song, Q; Cross, S; Misko, I; Lees-Miller, S P; Lavin, M F

1998-08-31

Burkitt's lymphoma cells that vary in their phenotypic characteristics show significantly different degrees of susceptibility to radiation-induced apoptosis. Propensity to undergo apoptosis is reflected in the degradation of substrates such as DNA-dependent protein kinase but the status of bcl-2, c-myc and p53 has been uninformative. In this study, we have focused on 2 Epstein-Barr virus (EBV)-associated Burkitt's cell lines, one (WW2) susceptible and the other (BL29) resistant to etoposide-induced apoptosis. Differences in expression of BHRF1, an EBV gene that is homologous to the Bcl-2 proto-oncogene and known to inhibit apoptosis, or changes in apoptosis inhibitory proteins (IAPs), did not appear to account for the difference in susceptibility in the 2 cell lines. Cytoplasmic extracts from etoposide-treated WW2 cells caused apoptotic changes in nuclei isolated from either BL29 or WW2 cells, whereas extracts from BL29 cells failed to do so. In addition, extracts from etoposide-treated WW2 cells degraded the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs), an important indicator of apoptosis, but this protein was resistant to degradation by BL29 extracts. It appears likely that caspase 3 (CPP32) is involved in this degradation since it was activated only in the apoptosis susceptible cells and the pattern of cleavage of DNA-PKcs was similar to that reported previously with recombinant caspase 3. As observed previously, addition of caspase 3 to nuclei failed to induce morphological changes indicative of apoptosis, but addition of caspase 3 to nuclei in the presence of extract from the resistant cells led to apoptotic changes. We conclude that resistance to apoptosis in BL29 cells is due to a failure of etoposide to activate upstream effectors of caspase activity.

Kinetics of apoptotic markers in exogeneously induced apoptosis of EL4 cells.

PubMed

Jessel, Robert; Haertel, Steffen; Socaciu, Carmen; Tykhonova, Svetlana; Diehl, Horst A

2002-01-01

We investigated the time-dependence of apoptotic events in EL4 cells by monitoring plasma membrane changes in correlation to DNA fragmentation and cell shrinkage. We applied three apoptosis inducers (staurosporine, tubericidine and X-rays) and we looked at various markers to follow the early-to-late apoptotic events: phospholipid translocation (identified through annexin V-fluorescein assay and propidium iodide), lipid package (via merocyanine assay), membrane fluidity and anisotropy (via fluorescent measurements), DNA fragmentation by the fluorescence-labeling test and cell size measurements. The different apoptotic inducers caused different reactions of the cells: staurosporine induced apoptosis most rapidly in a high number of cells, tubercidine triggered apoptosis only in the S phase cells, while X-rays caused a G2/M arrest and subsequently apoptosis. Loss of lipid asymmetry is promptly detectable after one hour of incubation time. The phosphatidylserine translocation, decrease of lipid package and anisotropy, and the increase of membrane fluidity appeared to be based on the same process of lipid asymmetry loss. Therefore, the DNA fragmentation and the cell shrinkage appear to be parallel and independent processes running on different time scales but which are kinetically inter-related. The results indicate different signal steps to apoptosis dependent on inducer characteristics but the kinetics of "early-to-late" apoptosis appears to be a fixed program.

TREATMENT OF OBSESSIVE COMPULSIVE SYMPTOMS IN SCHIZOPHRENIA WITH FLUOXETINE

PubMed Central

Agarwal, Vivek; Agarwal, K.M.

2000-01-01

Obsessive compulsive symptoms have been reported to occur in high proportion in schizophrenia. Presence of obsessive compulsive symptoms in schizophrenia has poor prognostic significance. Because of the antiobsessional effect of the fluoxetine, present study was undertaken as preliminary investigation in cases of schizophrenia with obsessive compulsive symptoms. We conducted an open trial of 12 weeks duration in which fluoxetine was added up to 80 mg to the maintenance neuroleptic medication of outpatients of schizophrenia with obsessive compulsive symptoms diagnosed by DSM-IV criteria. Five patients showed a significant reduction in scores of Positive and Negative Syndrome Scale, Yale Brown Obsessive Compulsive Scale and Clinical Global Impression Scale. Two patients did not show any response. Fluoxetine was well tolerated by all the patients. The positive findings of this preliminary investigation supports the further investigations of fluoxetine as potential treatment in the obsessive compulsive symptoms in schizophrenia. PMID:21407959

Effects of fluoxetine on the rat brain in the forced swimming test: a [F-18]FDG micro-PET imaging study.

PubMed

Jang, Dong-Pyo; Lee, So-Hee; Park, Chan-Woong; Lee, Sang-Yoon; Kim, Young-Bo; Cho, Zang-Hee

2009-02-13

We used the [F-18]FDG micro-PET neuroimaging to examine the effects of fluoxetine on brain activity in rats and on their behavioral response in the forced swimming test (FST). In the first experiment, the rats were administered doses of fluoxetine (10 or 20mg/kg) 24, 19 and 1h before the rat brains were scanned. Fluoxetine induced strong activation of the dorsal hippocampus and the deactivation of the inferior colliculus, medulla oblongata, and prelimbic cortex in a dose-dependent manner. These results seemed to be related with the changes in 5-HT (5-hydroxytryptamine, serotonin) levels after selective serotonin reuptake-inhibitor treatments. In the second experiment, the changes in glucose metabolism in the test session were measured after fluoxetine was given between pre-test and test sessions of the FST. Fluoxetine administration significantly decreased immobility behavior compared with saline administration. At the same time, the activity of the insular/piriform cortex decreased significantly. In contrast, the extent of cerebellar activation increased. The glucose metabolism of the dorsal hippocampus also increased, which suggests that post-stress changes in the facilitation of hippocampal serotonergic neurotransmission lead to decreased immobilization in the FST.

Fluoxetine impairs insulin secretion without modifying extracellular serotonin levels in MIN6 β-cells.

PubMed

Cataldo, L R; Cortés, V A; Mizgier, M L; Aranda, E; Mezzano, D; Olmos, P; Galgani, J E; Suazo, J; Santos, J L

2015-09-01

Pancreatic β-cells synthetize and store Serotonin (5-Hydroxytriptamine, 5HT) which is co-released with insulin. It has been proposed that extracellular 5HT binds to specific cell surface receptors and modulate insulin secretion. On the other hand, Selective Serotonin Reuptake Inhibitor (SSRI) fluoxetine seems to reduce Glucose-Stimulated Insulin Secretion (GSIS). However, it is unknown whether this effect results from changes in extracellular 5HT concentration owed to the blockade of 5HT transporter (SERT) or from non-5HT dependent actions. The aims of this work were: 1) to quantify extracellular 5HT levels and GSIS in β-cell lines, 2) to determine whether extracellular 5HT levels and GSIS are changed by fluoxetine or 5-Hydroxytryptophan (5HTP, the immediate 5HT biosynthetic precursor), and 3) to quantify the expression of Slc6a4 gene (encoding SERT) in β-cell lines in relation to other genes involved in 5HT system. β-cell lines MIN6 and RINm5f were subjected to GSIS protocols, after treatment with fluoxetine, 5HTP or 5HT. Insulin and 5HT were quantified by ELISA and HPLC, respectively. Relative mRNA expression was quantified by RT-qPCR. MIN6 β-cells secretes 5HT in response to glucose, showing a sharp increase in 5HT release when cells were preloaded with 5HTP. Treatment with 5HT or fluoxetine reduces GSIS. Fluoxetine fails to further increases 5HTP-induced elevation of secreted 5HT. MIN6 β-cells express both isoforms of Tryptophan Hydroxylase (Tph1 and Tph2), and have high expression levels of L-Dopa decarboxylase (Ddc), both enzymes involved in 5HT biosynthetic pathway, but do not express the 5HT transporters Slc6a4 or Slc6a3 (the Dopamine-5HT transporter) genes. The inhibitory effect of fluoxetine on β-cell glucose stimulated insulin secretion is not mediated by blockage of 5HT transporter through SERT. © Georg Thieme Verlag KG Stuttgart · New York.

Local antinociceptive action of fluoxetine in the rat formalin assay: role of l-arginine/nitric oxide/cGMP/KATP channel pathway.

PubMed

Ghorbanzadeh, Behnam; Mansouri, Mohammad Taghi; Naghizadeh, Bahareh; Alboghobeish, Soheila

2018-02-01

The present study was conducted to evaluate the local antinociceptive actions of fluoxetine, a selective serotonin reuptake inhibitor, and the possible involvement of the l-arginine/NO/cGMP/K ATP channel pathway in this effect using the formalin test in rats. To elucidate the underlying mechanisms, animals were pre-treated with l-NAME, aminoguanidine, methylene blue, glibenclamide, l-arginine, sodium nitroprusside, or diazoxide. Local ipsilateral, but not contralateral, administration of fluoxetine (10-300 μg/paw) dose-dependently suppressed flinching number during both early and late phases of the test, and this was comparable with morphine also given peripherally. Pre-treatment with l-NAME, aminoguanidine, methylene blue, or glibenclamide dose-dependently prevented fluoxetine (100 μg/paw)-induced antinociception in the late phase. In contrast, administration of l-arginine, sodium nitroprusside, and diazoxide significantly enhanced the antinociception caused by fluoxetine in the late phase of the test. However, these treatments had no significant effect on the antinociceptive response of fluoxetine in the early phase of the formalin test. Our data demonstrate that local peripheral antinociception of fluoxetine during the late phase of the formalin test could be due to activation of l-arginine/NO/cGMP/K ATP channel pathway. The peripheral action of fluoxetine raises the possibility that topical application of this drug (e.g., as a cream, ointment, or jelly) may be a useful method for relieving the inflammatory pain states.

Changes of cytosolic calcium and contractility of young rat vas deferens by acute treatment with amphetamine, fluoxetine or sibutramine.

PubMed

Jurkiewicz, Neide Hyppolito; da Silva Júnior, Edilson Dantas; de Souza, Bruno Palmieri; Ferreira Verde, Luciana; Drawanz Pereira, Janaina; Mendes Sobrinho, Cairo; Soubhi Smaili, Soraya; Caricati-Neto, Afonso; Miranda-Ferreira, Regiane; Jurkiewicz, Aron

2012-09-15

Previous studies conducted in our laboratory indicated that administration of amphetamine, fluoxetine or sibutramine affects the sympathetic nervous system of the rat vas deferens. Therefore, our goal was to verify the role of calcium in vasa deferentia from young rats pretreated with a single dose of these drugs. Young 40-day-old male Wistar rats were pretreated with amphetamine 3 mg/kg, fluoxetine 10 mg/kg or sibutramine 6 mg/kg for 4 h before the experiments. CaCl(2) (10 mM) was used to induce contraction through time-effect curves in calcium-free solution to measure phasic and tonic components. We also evaluated the calcium-induced fluorescence of vas deferens cut into thin slices. In rats pretreated with amphetamine, we found an increase of the tonic contraction component which was reduced by verapamil. The phasic and tonic responses were increased in the group treated with fluoxetine, but only the tonic response was more sensitive to the antagonism by verapamil. The group treated with sibutramine showed an increase of phasic response whereas the tonic component was decreased. In this group an increase of the affinity for verapamil antagonism was found. In the calcium fluorescence study it was observed that the group treated with amphetamine, fluoxetine or sibutramine showed higher basal Ca(2+) fluorescence after stimulus with KCl (70 mM), noradrenaline (10(-4)M) or acetylcholine (10(-4)M). In all pretreated groups the calcium fluorescence was diminished by nifedipine 10(-7)M. Therefore, the pretreatment with amphetamine, fluoxetine or sibutramine seems to affect the calcium contractility and homeostasis in young rat vas deferens. Copyright © 2012 Elsevier B.V. All rights reserved.

ERdj5 sensitizes neuroblastoma cells to endoplasmic reticulum stress-induced apoptosis.

PubMed

Thomas, Christophoros G; Spyrou, Giannis

2009-03-06

Down-regulation of the unfolded protein response (UPR) can be therapeutically valuable in cancer treatment, and endoplasmic reticulum (ER)-resident chaperone proteins may thus be targets for developing novel chemotherapeutic strategies. ERdj5 is a novel ER chaperone that regulates the ER-associated degradation of misfolded proteins through its associations with EDEM and the ER stress sensor BiP. To investigate whether ERdj5 can regulate ER stress signaling pathways, we exposed neuroblastoma cells overexpressing ERdj5 to ER stress inducers. ERdj5 promoted apoptosis in tunicamycin, thapsigargin, and bortezomib-treated cells. To provide further evidence that ERdj5 induces ER stress-regulated apoptosis, we targeted Bcl-2 to ER of ERdj5-overexpressing cells. Targeting the Bcl-2 to ER prevented the apoptosis induced by ER stress inducers but not by non-ER stress apoptotic stimuli, suggesting induction of ER stress-regulated apoptosis by ERdj5. ERdj5 enhanced apoptosis by abolishing the ER stress-induced phosphorylation of eukaryotic translation initiation factor 2alpha (eIF2alpha) and the subsequent translational repression. ERdj5 was found to inhibit the eIF2alpha phosphorylation under ER stress through inactivating the pancreatic endoplasmic reticulum kinase. The compromised integrated stress response observed in ERdj5-overexpressing ER-stressed cells due to repressed eIF2alpha phosphorylation correlated with impaired neuroblastoma cell resistance under ER stress. These results demonstrate that ERdj5 decreases neuroblastoma cell survival by down-regulating the UPR, raising the possibility that this protein could be a target for anti-tumor approaches.

Caspase-1 Inflammasome Activation Mediates Homocysteine-Induced Pyrop-Apoptosis in Endothelial Cells

PubMed Central

Xi, Hang; Zhang, Yuling; Xu, Yanjie; Yang, William Y; Jiang, Xiaohua; Sha, Xiaojin; Cheng, Xiaoshu; Wang, Jingfeng; Qin, Xuebin; Yu, Jun; Ji, Yong; Yang, Xiaofeng; Wang, Hong

2016-01-01

Rationale Endothelial injury is an initial mechanism mediating cardiovascular disease. Objective Here, we investigated the effect of hyperhomocysteinemia (HHcy) on programed cell death in endothelial cells (EC). Methods and Results We established a novel flow-cytometric gating method to define pyrotosis (Annexin V−/Propidium iodide+). In cultured human EC, we found that: 1). Hcy and Lipopolysaccharide (LPS) individually and synergistically induced inflammatory pyroptotic and non-inflammatory apoptotic cell death. 2). Hcy/LPS induced caspase-1 activation prior to caspase-8, -9, -3 activations. 3). Caspase-1/3 inhibitors rescued Hcy/LPS-induced pyroptosis/apoptosis, but caspase-8/9 inhibitors had differential rescue effect. 4). Hcy/LPS induced NLRP3 protein, caused NLRP3-containing inflammasome assembly, caspase-1 activation and IL-1β cleavage/activation. 5). Hcy/LPS elevated intracellular reactive oxidative species (ROS). 6). Intracellular oxidative gradient determined cell death destiny as intermediate intracellular ROS levels are associated with pyroptosis, whereas, high ROS corresponded to apoptosis. 7). Hcy/LPS induced mitochondrial membrane potential collapse and cytochrome-c release, and increased Bax/Bcl-2 ratio which were attenuated by antioxidants and caspase-1 inhibitor. 8). Antioxidants extracellular superoxide dismutase and catalase prevented Hcy/LPS-induced caspase-1 activation, mitochondrial dysfunction and pyroptosis/apoptosis. In cystathionine β-synthase deficient (Cbs−/−) mice, severe HHcy induced caspase-1 activation in isolated lung EC and caspase-1 expression in aortic endothelium, and elevated aortic caspase-1,9 protein/activity and Bax/Bcl-2 ratio in Cbs−/− aorta and HUVEC. Finally, Hcy-induced DNA fragmentation was reversed in caspase-1−/− EC. HHcy-induced aortic endothelial dysfunction was rescued in caspase-1−/− and NLRP3−/− mice. Conclusion HHcy preferentially induces EC pyroptosis via caspase-1-dependent

Curcumin induces Apaf-1-dependent, p21-mediated caspase activation and apoptosis

PubMed Central

Zhang, Honghao; Jones, Anthony; Verone, Alissa; Pitarresi, Jason; Jandhyam, Sirisha; Prabhu, Varun; Black, Jennifer D

2011-01-01

Previous studies have demonstrated that curcumin induces mitochondria-mediated apoptosis. However, understanding of the molecular mechanisms underlying curcumin-induced cell death remains limited. In this study, we demonstrate that curcumin treatment of cancer cells caused dose- and time-dependent caspase 3 activation, which is required for apoptosis as confirmed using the pan-caspase inhibitor, z-VAD. Knockdown experiments and knockout cells excluded a role for caspase 8 in curcumin-induced caspase 3 activation. In contrast, Apaf-1 deficiency or silencing inhibited the activity of caspase 3, pointing to a requisite role of Apaf-1 in curcumin-induced apoptotic cell death. Curcumin treatment led to Apaf-1 upregulation, both at the protein and mRNA levels. Cytochrome c release from mitochondria to the cytosol in curcumin-treated cells was associated with upregulation of pro-apoptotic proteins, such as Bax, Bak, Bid and Bim. Cross-linking experiments demonstrated Bax oligomerization during curcumin-induced apoptosis, suggesting that induced expression of Bax, Bid and Bim causes Bax channel formation on the mitochondrial membrane. The release of cytochrome c was unaltered in p53-deficient cells, whereas absence of p21 blocked cytochrome c release, caspase activation and apoptosis. Importantly, p21 deficiency resulted in reduced expression of Apaf-1 during curcumin treatment, indicating a requirement for p21 in Apaf-1-dependent caspase activation and apoptosis. Together, our findings identify Apaf-1, Bax and p21 as novel potential targets for curcumin or curcumin-based anticancer agents. PMID:22101335

Amphiregulin suppresses epithelial cell apoptosis in lipopolysaccharide-induced lung injury in mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ogata-Suetsugu, Saiko; Yanagihara, Toyoshi; Hamada, Naoki

Background and objective: As a member of the epidermal growth factor family, amphiregulin contributes to the regulation of cell proliferation. Amphiregulin was reported to be upregulated in damaged lung tissues in patients with chronic obstructive pulmonary disease and asthma and in lung epithelial cells in a ventilator-associated lung injury model. In this study, we investigated the effect of amphiregulin on lipopolysaccharide (LPS)-induced acute lung injury in mice. Methods: Acute lung injury was induced by intranasal instillation of LPS in female C57BL/6 mice, and the mice were given intraperitoneal injections of recombinant amphiregulin or phosphate-buffered saline 6 and 0.5 h before andmore » 3 h after LPS instillation. The effect of amphiregulin on apoptosis and apoptotic pathways in a murine lung alveolar type II epithelial cell line (LA-4 cells) were examined using flow cytometry and western blotting, respectively. Results: Recombinant amphiregulin suppressed epithelial cell apoptosis in LPS-induced lung injury in mice. Western blotting revealed that amphiregulin suppressed epithelial cell apoptosis by inhibiting caspase-8 activity. Conclusion: Amphiregulin signaling may be a therapeutic target for LPS-induced lung injury treatment through its prevention of epithelial cell apoptosis. - Highlights: • Amphiregulin suppresses epithelial cell apoptosis in LPS-induced lung injury in mice. • The mechanism relies on inhibiting caspase-8 activity. • Amphiregulin signaling may be a therapeutic target for LPS-induced lung injury.« less

TRAIL Enhances Shikonin Induced Apoptosis through ROS/JNK Signaling in Cholangiocarcinoma Cells.

PubMed

Zhou, Guangyao; Yang, Zuqin; Wang, Xiaodong; Tao, Ran; Zhou, Yuanping

2017-01-01

Cholangiocarcinoma (CCA), arising from varying locations within the biliary tree, is the second most common primary liver malignancy worldwide. Shikonin, an active compound extracted from the Chinese herb Zicao, holds anti-bacterial, anti-inflammatory, and anti-tumor activities. However, the effect of shikonin on human cholangiocarcinoma and detailed mechanisms of TRAIL enhancement remains to be elucidated. The purpose of the study was to investigate the protective functions of TRAIL enhancement for shikonin induced apoptosis in cholangiocarcinoma cells. We use MTT assay, apoptosis assay, caspase activity assay, flow cytometry assay, real time PCR and Western blot to observe the effects of TRAIL on shikonin induced cholangiocarcinoma cells apoptosis and its mechanism. Shikonin inhibited cell viability and induced apoptosis of CCA cells, effects enhanced by TRAIL treatment via activation of caspase-3, -8, -9. Furhermore, TRAIL enhanced anti-proliferation of shikonin and shikonin induced apoptosis through induction of ROS mediated JNK activation, while AKT activation had an effect on shikonin anti-proliferation activity, but not in the TRAIL enhanced counterparts. Finally, shikonin upregulated DR5 expression, an effect essential for TRAIL-enhanced activities of shikonin in RBE cells. Our results revealed that shikonin could inhibit cells viability and induce apoptosis of CCA cells, effects enhanced by TRAIL treatment via ROS mediated JNK signalling pathways, involving up-regulation of DR5 expression. Our results provide further insight into the mechanism underlying the anti-tumor effects of shikonin by TRAIL enhanced in CCA and a new therapeutic strategy to CCA treatment. © 2017 The Author(s). Published by S. Karger AG, Basel.

Bacopa monnieri-Induced Protective Autophagy Inhibits Benzo[a]pyrene-Mediated Apoptosis.

PubMed

Das, Durgesh Nandini; Naik, Prajna Paramita; Nayak, Aditi; Panda, Prashanta Kumar; Mukhopadhyay, Subhadip; Sinha, Niharika; Bhutia, Sujit K

2016-11-01

Benzo[a]pyrene (B[a]P) is capable of inducing oxidative stress and cellular injuries leading to cell death and associates with a significant risk of cancer development. Prevention of B[a]P-induced cellular toxicity with herbal compound through regulation of mitochondrial oxidative stress might protect cell death and have therapeutic benefit to human health. In this study, we demonstrated the cytoprotective role of Bacopa monnieri (BM) against B[a]P-induced apoptosis through autophagy induction. Pretreatment with BM rescued the reduction in cell viability in B[a]P-treated human keratinocytes (HaCaT) cells indicating the cytoprotective potential of BM against B[a]P. Moreover, BM was found to inhibit B[a]P-mediated reactive oxygen species (ROS)-induced apoptosis activation in HaCaT cells. Furthermore, BM was found to preserve mitochondrial membrane potential and inhibited release of cytochrome c in B[a]P-treated HaCaT cells. Bacopa monnieri induced protective autophagy; we knocked down Beclin-1, and data showed that BM was unable to protect from B[a]P-induced mitochondrial ROS-mediated apoptosis in Beclin-1-deficient HaCaT cells. Moreover, we established that B[a]P-induced damaged mitochondria were found to colocalize and degraded within autolysosomes in order to protect HaCaT cells from mitochondrial injury. In conclusion, B[a]P-induced apoptosis was rescued by BM treatment and provided cytoprotection through Beclin-1-dependent autophagy activation. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

A novel role for the apoptosis inhibitor ARC in suppressing TNFα-induced regulated necrosis

PubMed Central

Kung, G; Dai, P; Deng, L; Kitsis, R N

2014-01-01

TNFα signaling can promote apoptosis or a regulated form of necrosis. ARC (apoptosis repressor with CARD (caspase recruitment domain)) is an endogenous inhibitor of apoptosis that antagonizes both the extrinsic (death receptor) and intrinsic (mitochondrial/ER) apoptosis pathways. We discovered that ARC blocks not only apoptosis but also necrosis. TNFα-induced necrosis was abrogated by overexpression of wild-type ARC but not by a CARD mutant that is also defective for inhibition of apoptosis. Conversely, knockdown of ARC exacerbated TNFα-induced necrosis, an effect that was rescued by reconstitution with wild-type, but not CARD-defective, ARC. Similarly, depletion of ARC in vivo exacerbated necrosis caused by infection with vaccinia virus, which elicits severe tissue damage through this pathway, and sensitized mice to TNFα-induced systemic inflammatory response syndrome. The mechanism underlying these effects is an interaction of ARC with TNF receptor 1 that interferes with recruitment of RIP1, a critical mediator of TNFα-induced regulated necrosis. These findings extend the role of ARC from an apoptosis inhibitor to a regulator of the TNFα pathway and an inhibitor of TNFα-mediated regulated necrosis. PMID:24440909

Autophagy mediated CoCrMo particle-induced peri-implant osteolysis by promoting osteoblast apoptosis

PubMed Central

Wang, Zhenheng; Liu, Naicheng; Liu, Kang; Zhou, Gang; Gan, Jingjing; Wang, Zhenzhen; Shi, Tongguo; He, Wei; Wang, Lintao; Guo, Ting; Bao, Nirong; Wang, Rui; Huang, Zhen; Chen, Jiangning; Dong, Lei; Zhao, Jianning; Zhang, Junfeng

2015-01-01

Wear particle-induced osteolysis is the leading cause of aseptic loosening, which is the most common reason for THA (total hip arthroplasty) failure and revision surgery. Although existing studies suggest that osteoblast apoptosis induced by wear debris is involved in aseptic loosening, the underlying mechanism linking wear particles to osteoblast apoptosis remains almost totally unknown. In the present study, we investigated the effect of autophagy on osteoblast apoptosis induced by CoCrMo metal particles (CoPs) in vitro and in a calvarial resorption animal model. Our study demonstrated that CoPs stimulated autophagy in osteoblasts and PIO (particle-induced osteolysis) animal models. Both autophagy inhibitor 3-MA (3-methyladenine) and siRNA of Atg5 could dramatically reduce CoPs-induced apoptosis in osteoblasts. Further, inhibition of autophagy with 3-MA ameliorated the severity of osteolysis in PIO animal models. Moreover, 3-MA also prevented osteoblast apoptosis in an antiautophagic way when tested in PIO model. Collectively, these results suggest that autophagy plays a key role in CoPs-induced osteolysis and that targeting autophagy-related pathways may represent a potential therapeutic approach for treating particle-induced peri-implant osteolysis. PMID:26566231

Fluoxetine increases the activity of the ERK-CREB signal system and alleviates the depressive-like behavior in rats exposed to chronic forced swim stress.

PubMed

Qi, Xiaoli; Lin, Wenjuan; Li, Junfa; Li, Huanhuan; Wang, Weiwen; Wang, Donglin; Sun, Meng

2008-08-01

Our previous research indicates that the extracellular signal-regulated kinase (ERK)-cyclic AMP-responsive-element-binding protein (CREB) signal system may be involved in the molecular mechanism of depression. The present study further investigated the effect of antidepressant fluoxetine on the ERK-CREB signal system and the depressive-like behaviors in rats. Fluoxetine was administrated to either naive rats or stressed rats for 21 days. The results showed that chronic forced swim stress induced depressive-like behaviors and decreased the levels of P-ERK2, P-CREB, ERK1/2 and CREB in hippocampus and prefrontal cortex. Fluoxetine alleviated the depressive-like behaviors and reversed the disruptions of the P-ERK2 and P-CREB in stressed rats. Fluoxetine also exerted mood-elevating effect and increased the levels of the P-ERK2 and P-CREB in naive rats. These results suggest that the ERK-CREB signal system may be the targets of the antidepressant action of fluoxetine and participate in the neuronal mechanism of depression.

BIM is the primary mediator of MYC-induced apoptosis in multiple solid tissues.

PubMed

Muthalagu, Nathiya; Junttila, Melissa R; Wiese, Katrin E; Wolf, Elmar; Morton, Jennifer; Bauer, Barbara; Evan, Gerard I; Eilers, Martin; Murphy, Daniel J

2014-09-11

MYC is one of the most frequently overexpressed oncogenes in human cancer, and even modestly deregulated MYC can initiate ectopic proliferation in many postmitotic cell types in vivo. Sensitization of cells to apoptosis limits MYC's oncogenic potential. However, the mechanism through which MYC induces apoptosis is controversial. Some studies implicate p19ARF-mediated stabilization of p53, followed by induction of proapoptotic BH3 proteins NOXA and PUMA, whereas others argue for direct regulation of BH3 proteins, especially BIM. Here, we use a single experimental system to systematically evaluate the roles of p19ARF and BIM during MYC-induced apoptosis, in vitro, in vivo, and in combination with a widely used chemotherapeutic, doxorubicin. We find a common specific requirement for BIM during MYC-induced apoptosis in multiple settings, which does not extend to the p53-responsive BH3 family member PUMA, and find no evidence of a role for p19ARF during MYC-induced apoptosis in the tissues examined. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Effects of co-administration of fluoxetine or tianeptine with metyrapone on immobility time and plasma corticosterone concentration in rats subjected to the forced swim test.

PubMed

Rogóz, Zofia; Skuza, Grazyna; Leśkiewicz, Monika; Budziszewska, Bogusława

2008-01-01

Major depression is frequently associated with hyperactivity of the hypothalamic-pituitary-adrenocortical axis, and glucocorticoid synthesis inhibitors have been shown to exert antidepressant action. The aim of the present study was to examine the effect of co-administration of fluoxetine or tianeptine with metyrapone on immobility time and plasma corticosterone concentration in male Wistar rats subjected to the forced swim test. Metyrapone alone (50 mg/kg, but not 25 mg/kg) reduced the immobility time of rats in the forced swim test; moreover, both doses tested (25 and 50 mg/kg), dose-dependently decreased the stress-induced plasma corticosterone concentration. Joint administration of fluoxetine or tianeptine (10 mg/kg) and metyrapone (25 mg/kg - a dose inactive per se) exhibited antidepressant-like activity in the forced swim test in rats. WAY 100636 (a 5-HT(1A) antagonist), but not prazosin (an alpha(1)-adrenergic antagonist), used in doses ineffective in the forced swim test, inhibited the antidepressant-like effect induced by co-administration of fluoxetine or tianeptine with metyrapone (25 mg/kg). Combined treatment of fluoxetine or tianeptine and metyrapone inhibited stress-induced corticosterone secretion to a similar extent as metyrapone alone. The obtained results indicate that metyrapone potentiates the antidepressant-like activity of fluoxetine or tianeptine and that, among other mechanisms, 5-HT(1A) receptors may play some role in this effect. Moreover, metyrapone exerts a beneficial effect on the stress-induced increase in plasma corticosterone concentration. These findings suggest that the co-administration of metyrapone and an antidepressant drug may be useful for the treatment of drug-resistant depression and/or depression associated with a high cortisol level.

Chloral Hydrate Treatment Induced Apoptosis of Macrophages via Fas Signaling Pathway.

PubMed

Cai, Jun; Peng, Yanxia; Chen, Ting; Liao, Huanjin; Zhang, Lifang; Chen, Qiuhua; He, Yiming; Wu, Ping; Xie, Tong; Pan, Qingjun

2016-12-10

BACKGROUND There are recent reports on several anesthetics that have anti-inflammatory and anti-infective effects apart from their uses for pain relief and muscle relaxation. Chloral hydrate is a clinical anesthetic drug and sedative that has also been reported to attenuate inflammatory response, but the mechanisms are not clearly understood. MATERIAL AND METHODS This study investigated the effect of chloral hydrate treatment on the apoptosis of macrophages and explored the underlying mechanisms. RAW264.7 macrophages were treated with various concentrations of chloral hydrate for various lengths of time. Morphological changes were observed under a light microscope and apoptosis was detected with annexin-V-FITC/PI double-staining assay, Hochest 33258 and DNA ladder assay, the expression of Fas/FasL was detected with a flow cytometer, and the Fas signaling pathway was assessed by Western blotting. RESULTS The results showed that chloral hydrate treatment induced the morphology of RAW264.7 macrophages to change shape from typical fusiform to round in a concentration- and time-dependent manner, and was finally suspended in the supernatant. For the induction of apoptosis, chloral hydrate treatment induced the apoptosis of RAW264.7 macrophages from early-to-late stage apoptosis in a concentration- and time-dependent manner. For the mechanism, chloral hydrate treatment induced higher expression of Fas on RAW264.7 macrophages, and was also associated with changes in the expression of proteins involved in Fas signaling pathways. CONCLUSIONS Chloral hydrate treatment can induce the apoptosis of RAW264.7 macrophages through the Fas signaling pathway, which may provide new options for adjunctive treatment of acute inflammation.

Chloral Hydrate Treatment Induced Apoptosis of Macrophages via Fas Signaling Pathway

PubMed Central

Cai, Jun; Peng, Yanxia; Chen, Ting; Liao, Huanjin; Zhang, Lifang; Chen, Qiuhua; He, Yiming; Wu, Ping; Xie, Tong; Pan, Qingjun

2016-01-01

Background There are recent reports on several anesthetics that have anti-inflammatory and anti-infective effects apart from their uses for pain relief and muscle relaxation. Chloral hydrate is a clinical anesthetic drug and sedative that has also been reported to attenuate inflammatory response, but the mechanisms are not clearly understood. Material/Methods This study investigated the effect of chloral hydrate treatment on the apoptosis of macrophages and explored the underlying mechanisms. RAW264.7 macrophages were treated with various concentrations of chloral hydrate for various lengths of time. Morphological changes were observed under a light microscope and apoptosis was detected with annexin-V-FITC/PI double-staining assay, Hochest 33258 and DNA ladder assay, the expression of Fas/FasL was detected with a flow cytometer, and the Fas signaling pathway was assessed by Western blotting. Results The results showed that chloral hydrate treatment induced the morphology of RAW264.7 macrophages to change shape from typical fusiform to round in a concentration- and time-dependent manner, and was finally suspended in the supernatant. For the induction of apoptosis, chloral hydrate treatment induced the apoptosis of RAW264.7 macrophages from early-to-late stage apoptosis in a concentration- and time-dependent manner. For the mechanism, chloral hydrate treatment induced higher expression of Fas on RAW264.7 macrophages, and was also associated with changes in the expression of proteins involved in Fas signaling pathways. Conclusions Chloral hydrate treatment can induce the apoptosis of RAW264.7 macrophages through the Fas signaling pathway, which may provide new options for adjunctive treatment of acute inflammation. PMID:27941708

Bupivacaine-induced apoptosis independently of WDR35 expression in mouse neuroblastoma Neuro2a cells

PubMed Central

2012-01-01

Background Bupivacaine-induced neurotoxicity has been shown to occur through apoptosis. Recently, bupivacaine was shown to elicit reactive oxygen species (ROS) production and induce apoptosis accompanied by activation of p38 mitogen-activated protein kinase (MAPK) in a human neuroblastoma cell line. We have reported that WDR35, a WD40-repeat protein, may mediate apoptosis through caspase-3 activation. The present study was undertaken to test whether bupivacaine induces apoptosis in mouse neuroblastoma Neuro2a cells and to determine whether ROS, p38 MAPK, and WDR35 are involved. Results Our results showed that bupivacaine induced ROS generation and p38 MAPK activation in Neuro2a cells, resulting in apoptosis. Bupivacaine also increased WDR35 expression in a dose- and time-dependent manner. Hydrogen peroxide (H2O2) also increased WDR35 expression in Neuro2a cells. Antioxidant (EUK-8) and p38 MAPK inhibitor (SB202190) treatment attenuated the increase in caspase-3 activity, cell death and WDR35 expression induced by bupivacaine or H2O2. Although transfection of Neuro2a cells with WDR35 siRNA attenuated the bupivacaine- or H2O2-induced increase in expression of WDR35 mRNA and protein, in contrast to our previous studies, it did not inhibit the increase in caspase-3 activity in bupivacaine- or H2O2-treated cells. Conclusions In summary, our results indicated that bupivacaine induced apoptosis in Neuro2a cells. Bupivacaine induced ROS generation and p38 MAPK activation, resulting in an increase in WDR35 expression, in these cells. However, the increase in WDR35 expression may not be essential for the bupivacaine-induced apoptosis in Neuro2a cells. These results may suggest the existence of another mechanism of bupivacaine-induced apoptosis independent from WDR35 expression in Neuro2a cells. PMID:23227925

Butyric Acid-Induced T-Cell Apoptosis Is Mediated by Caspase-8 and -9 Activation in a Fas-Independent Manner

PubMed Central

Kurita-Ochiai, Tomoko; Ochiai, Kuniyasu; Fukushima, Kazuo

2001-01-01

Our previous study demonstrated that butyric acid, an extracellular metabolite of periodontopathic bacteria, induced apoptosis in murine thymocytes, splenic T cells, and human Jurkat cells. In this study, we examined whether CD95 ligand-receptor interaction is involved in butyric acid-induced T-cell apoptosis. Flow cytometry analysis indicated that expression of Fas in Jurkat and T cells from peripheral blood mononuclear cells was not affected by butyric acid treatment. Furthermore, the expression of Fas and FasL protein in Western blotting was not affected by butyric acid treatment. Coincubation with blocking anti-Fas antibodies prevented Fas-induced apoptosis but not butyric acid-induced apoptosis. Anti-FasL antibodies also did not prevent butyric acid-induced apoptosis at any dose examined. Although cytotoxic anti-Fas antibody affected butyric acid-induced apoptosis, a synergistic effect was not seen. Time-dependent activation of caspase-8 and -9 was recognized in butyric acid- as well as Fas-mediated apoptosis. IETD-CHO and LEHD-CHO, specific inhibitors of caspase-8 and -9, respectively, completely blocked Fas-mediated apoptosis and partially prevented butyric acid-induced apoptosis. These results suggest that the Fas-FasL interaction is not involved in butyric acid-induced apoptosis and that caspase-8 and -9-dependent apoptosis plays an important role in butyric acid-induced apoptosis, as well as Fas-induced apoptosis. PMID:11238216

Dihydroartemisinin-induced apoptosis in human acute monocytic leukemia cells

PubMed Central

Cao, Jia-Tian; Mo, Hui-Min; Wang, Yue; Zhao, Kai; Zhang, Tian-Tian; Wang, Chang-Qian; Xu, Kai-Lin; Han, Zhi-Hua

2018-01-01

Dihydroartemisinin (DHA) is a derivative of artemisinin. The present study aimed to investigate whether DHA induces apoptosis in the THP-1 human acute monocytic leukemia cell line (AMoL), and to identify the relative molecular mechanisms. The results of the present study demonstrated that the viability of THP-1 cells were inhibited by DHA in a dose- and time-dependent manner, which was accompanied by morphological characteristics associated with apoptosis. After 24 h of 200 µM DHA treatment, the proportion of apoptotic cells was significantly increased compared with the untreated controls (P<0.01). In addition, DHA downregulated the levels of B-cell lymphoma (Bcl)-2, protein kinase B (Akt)1, Akt2 and Akt3 gene expression, and increased the expression of the Bcl-2-associated X protein apoptosis regulator. The protein expression of phospho-Akt and phospho-extracellular signal-regulated kinase (ERK) was also decreased, and the protein expression level of cleaved caspase-3 was increased following treatment with DHA. Therefore, DHA may induce apoptosis in the AMoL THP-1 cell line via currently unknown underlying molecular mechanisms, including the downregulation of ERK and Akt, and the activation of caspase-3. PMID:29435054

HAT1 induces lung cancer cell apoptosis via up regulating Fas.

PubMed

Han, Na; Shi, Lei; Guo, Qiuyun; Sun, Wei; Yu, Yang; Yang, Li; Zhang, Xiaoxi; Zhang, Mengxian

2017-10-27

The dysfunction of apoptosis is one of the factors contributing to lung cancer (LC) growth. Histone acetyltransferase HAT1 can up regulate cell apoptosis. This study aims to investigate the mechanism by which HAT1 induces LC cell (LCC) apoptosis via up regulating the expression of Fas. In this study, the surgically removed human LC tissues were collected. LCCs were isolated from the LC tissues and analyzed for the expression of HAT1 and Fas by RT-qPCR and Western blotting. We observed that the expression of Fas was negatively correlated with PAR2 in LCCs. Activation of PAR2 suppressed the expression of Fas in normal lung epithelial cells. The expression of HAT1 was lower and positively correlated with Fas expression and negatively correlated with PAR2 expression in LCCs. Activation of PAR2 suppressed Fas expression in lung epithelial cells via inhibiting HAT1. Restoration of HAT1 expression restored Fas expression in LCCs and induced LCC apoptosis. In conclusion, less expression of HAT1 in LCCs was associated with the pathogenesis of LC. Up regulation of HAT1 expression in LCCs can induce LCCs apoptosis, which may be a potential novel therapy for the treatment of LC.

Depressive-like behaviour induced by an intracerebroventricular injection of streptozotocin in mice: the protective effect of fluoxetine, antitumour necrosis factor-α and thalidomide therapies.

PubMed

Souza, Leandro C; Filho, Carlos B; Fabbro, Lucian D; de Gomes, Marcelo G; Goes, André T R; Jesse, Cristiano R

2013-04-01

Information on the effect of an intracerebroventricular (i.c.v.) injection of streptozotocin (STZ) on noncognitive behaviour in rodents such as depression states is scarce. Thus, the aim of this study was to examine the depressive-like effect of STZ injected by the i.c.v. route in mice and the potential protective effect of fluoxetine, antitumour necrosis factor-α (anti-TNF-α) and thalidomide. Our results indicated that a single injection of STZ (0.1 mg/site) promoted depressive-like behaviour in the tail suspension and sucrose preference tests without altering either locomotor activity or plasma glucose levels. We also showed that STZ increased TNF-α levels in the hippocampus of mice. Fluoxetine (32 mg/kg, intraperitoneally. 30 min before STZ injection), and the anti-TNF-α antibody (0.1 pg/site, i.c.v.) and thalidomide (3 mg/kg, subcutaneously), coadministered with STZ, prevented these effects. This is the first study to report depressive-like effects of STZ using the i.c.v. route in mice. We concluded that fluoxetine, anti-TNF-α antibody and thalidomide were effective in preventing depressive-like behaviour and the increase in TNF-α levels in the hippocampus of mice induced by an i.c.v. injection of STZ, reinforcing the involvement of TNF-α in the pathophysiology of depression. This model and the mechanisms studied may contribute towards the development of new antidepressant drugs and enhance the options for studying depression.

Antidepressant behavioral effects of duloxetine and fluoxetine in the rat forced swimming test.

PubMed

Ciulla, Leandro; Menezes, Honório Sampaio; Bueno, Bárbara Beatriz Moreira; Schuh, Alexandre; Alves, Rafael José Vargas; Abegg, Milena Pacheco

2007-01-01

To compare the effects of the antidepressant drugs duloxetine and fluoxetine on depressive behaviors in rodents. Eighteen male Wistar rats were given systemic injections of duloxetine, fluoxetine, or saline prior to a Forced Swimming Test (FST). Immobility and number of stops were measured. Rats given injections of fluoxetine displayed significantly less immobility (p = 0.02) and fewer stops than the control group (p = 0.003). Duloxetine significantly reduced the number of stops (p = 0.003), but did not effect immobility (p = 0.48). Duloxetine and fluoxetine reduced depressive behaviors in the Forced FST. However, our findings suggest that fluoxetine is more effective than duloxetine.

The role of apoptosis in MCLR-induced developmental toxicity in zebrafish embryos.

PubMed

Zeng, Cheng; Sun, Hong; Xie, Ping; Wang, Jianghua; Zhang, Guirong; Chen, Nan; Yan, Wei; Li, Guangyu

2014-04-01

We previously demonstrated that cyanobacteria-derived microcystin-leucine-arginine (MCLR) is able to induce developing toxicity, such as malformation, growth delay and also decreased heart rates in zebrafish embryos. However, the molecular mechanisms by which MCLR induces its toxicity during the development of zebrafish remain largely unknown. Here, we evaluate the role of apoptosis in MCLR-induced developmental toxicity. Zebrafish embryos were exposed to various concentrations of MCLR (0, 0.2, 0.5, 2, and 5.0 mg L(-1)) for 96 h, at which time reactive oxygen species (ROS) was significantly induced in the 2 and 5.0 mg L(-1) MCLR exposure groups. Acridine orange (AO) staining and terminal deoxynucleotide transferase-mediated deoxy-UTP nick end labelling (TUNEL) assay showed that MCLR exposure resulted in cell apoptosis. To test the apoptotic pathway, the expression pattern of several apoptotic-related genes was examined for the level of enzyme activity, gene and protein expression, respectively. The overall results demonstrate that MCLR induced ROS which consequently triggered apoptosis in the heart of developing zebrafish embryos. Our results also indicate that the p53-Bax-Bcl-2 pathway and the caspase-dependent apoptotic pathway play major roles in MCLR-induced apoptosis in the developing embryos. Copyright © 2014 Elsevier B.V. All rights reserved.

Delayed Cell Cycle Progression and Apoptosis Induced by Hemicellulase-Treated Agaricus blazei

PubMed Central

Kasai, Hirotake

2007-01-01

We examined the effects of hemicellulase-treated Agaricus blazei (AB fraction H, ABH) on growth of several tumor cell lines. ABH inhibited the proliferation of some cell lines without cytotoxic effects. It markedly prolonged the S phase of the cell cycle. ABH also induced mitochondria-mediated apoptosis in different cell lines. However, it had no impact on the growth of other cell lines. ABH induced strong activation of p38 mitogen-activated protein kinase (MAPK) in the cells in which it evoked apoptosis. On the other hand, ABH showed only a weak p38 activation effect in those cell lines in which it delayed cell cycle progression with little induction of apoptosis. However, p38 MAPK-specific inhibitor inhibited both ABH-induced effects, and ABH also caused apoptosis in the latter cells under conditions of high p38 MAPK activity induced by combined treatment with TNF-α. These results indicate that the responsiveness of p38 MAPK to ABH, which differs between cell lines, determines subsequent cellular responses on cell growth. PMID:17342245

Palmitate induces VSMC apoptosis via toll like receptor (TLR)4/ROS/p53 pathway.

PubMed

Zhang, Yuanjun; Xia, Guanghao; Zhang, Yaqiong; Liu, Juxiang; Liu, Xiaowei; Li, Weihua; Lv, Yaya; Wei, Suhong; Liu, Jing; Quan, Jinxing

2017-08-01

Toll-like receptor 4 (TLR4) has been implicated in vascular inflammation, as well as in the pathogenesis of atherosclerosis and diabetes. Vascular smooth muscle cell (VSMC) apoptosis has been shown to induce plaque vulnerability in atherosclerosis. Previous studies reported that palmitate induced apoptosis in VSMCs; however, the role of TLR4 in palmitate-induced apoptosis in VSMCs has not yet been defined. In this study, we investigated whether or not palmitate-induced apoptosis depended on the activation of the TLR4 pathway. VSMCs were treated with or without palmitate, CRISPR/Cas9z-mediated genome editing methods were used to deplete TLR4 expression, while NADPH oxidase inhibitors were used to inhibit reactive oxygen species (ROS) generation. Cell apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, ROS was measured using the 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) method, the mRNA and protein expression levels of caspase 3, caspase 9, BCL-2 and p53 were studied by real-time polymerase chain reaction (RT-PCR) and ELISA. Palmitate significantly promotes VSMC apoptosis, ROS generation, and expression of caspase 3, caspase 9 and p53; while NADPH oxidase inhibitor pretreatment markedly attenuated these effects. Moreover, knockdown of TLR4 significantly blocked palmitate-induced ROS generation and VSMC apoptosis accompanied by inhibition of caspase 3, caspase 9, p53 expression and restoration of BCL-2 expression. Our results suggest that palmitate-induced apoptosis depends on the activation of the TLR4/ROS/p53 signaling pathway, and that TLR4 may be a potential therapeutic target for the prevention and treatment of atherosclerosis. Copyright © 2017 Elsevier B.V. All rights reserved.

Cyclic GMP protects human macrophages against peroxynitrite-induced apoptosis.

PubMed

Shaw, Catherine A; Webb, David J; Rossi, Adriano G; Megson, Ian L

2009-05-07

Nitric oxide (NO) can be both pro- and anti-apoptotic in various cell types, including macrophages. This apparent paradox may result from the actions of NO-related species generated in the microenvironment of the cell, for example the formation of peroxynitrite (ONOO-). In this study we have examined the ability of NO and ONOO- to evoke apoptosis in human monocyte-derived macrophages (MDMvarphi), and investigated whether preconditioning by cyclic guanosine monophosphate (cGMP) is able to limit apoptosis in this cell type. Characterisation of the NO-related species generated by (Z)-1- [2-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate (DETA/NO) and 1,2,3,4-oxatriazolium, 5-amino-3-(3,4-dichlorophenyl)-, chloride (GEA-3162) was performed by electrochemistry using an isolated NO electrode and electron paramagnetic resonance (EPR) spectrometry. Mononuclear cells were isolated from peripheral blood of healthy volunteers and cultured to allow differentiation into MDMvarphi. Resultant MDMvarphi were treated for 24 h with DETA/NO (100 - 1000 muM) or GEA-3162 (10 - 300 muM) in the presence or absence of BAY 41-2272 (1 muM), isobutylmethylxanthine (IBMX; 1 muM), 1H- [1,2,4]oxadiazolo [4,3-a]quinoxalin-1-one (ODQ; 20 muM) or 8-bromo-cGMP (1 mM). Apoptosis in MDMvarphi was assessed by flow cytometric analysis of annexin V binding in combination with propidium iodide staining. Electrochemistry and EPR revealed that DETA/NO liberated free NO radical, whilst GEA-3162 concomitantly released NO and O2-, and is therefore a ONOO- generator. NO (DETA/NO) had no effect on cell viability, but ONOO- (GEA-3162) caused a concentration-dependent induction of apoptosis in MDMvarphi. Preconditioning of MDMvarphi with NO in combination with the phosphodiesterase inhibitor, 3-Isobutyl-1-methylxanthine (IBMX), or the NO-independent stimulator of soluble guanylate cyclase, BAY 41-2272, significantly attenuated ONOO--induced apoptosis in a cGMP-dependent manner. These results

Cyclic GMP protects human macrophages against peroxynitrite-induced apoptosis

PubMed Central

Shaw, Catherine A; Webb, David J; Rossi, Adriano G; Megson, Ian L

2009-01-01

Background Nitric oxide (NO) can be both pro- and anti-apoptotic in various cell types, including macrophages. This apparent paradox may result from the actions of NO-related species generated in the microenvironment of the cell, for example the formation of peroxynitrite (ONOO-). In this study we have examined the ability of NO and ONOO- to evoke apoptosis in human monocyte-derived macrophages (MDMϕ), and investigated whether preconditioning by cyclic guanosine monophosphate (cGMP) is able to limit apoptosis in this cell type. Methods Characterisation of the NO-related species generated by (Z)-1- [2-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate (DETA/NO) and 1,2,3,4-oxatriazolium, 5-amino-3-(3,4-dichlorophenyl)-, chloride (GEA-3162) was performed by electrochemistry using an isolated NO electrode and electron paramagnetic resonance (EPR) spectrometry. Mononuclear cells were isolated from peripheral blood of healthy volunteers and cultured to allow differentiation into MDMϕ. Resultant MDMϕ were treated for 24 h with DETA/NO (100 – 1000 μM) or GEA-3162 (10 – 300 μM) in the presence or absence of BAY 41–2272 (1 μM), isobutylmethylxanthine (IBMX; 1 μM), 1H- [1,2,4]oxadiazolo [4,3-a]quinoxalin-1-one (ODQ; 20 μM) or 8-bromo-cGMP (1 mM). Apoptosis in MDMϕ was assessed by flow cytometric analysis of annexin V binding in combination with propidium iodide staining. Results Electrochemistry and EPR revealed that DETA/NO liberated free NO radical, whilst GEA-3162 concomitantly released NO and O2-, and is therefore a ONOO- generator. NO (DETA/NO) had no effect on cell viability, but ONOO- (GEA-3162) caused a concentration-dependent induction of apoptosis in MDMϕ. Preconditioning of MDMϕ with NO in combination with the phosphodiesterase inhibitor, 3-Isobutyl-1-methylxanthine (IBMX), or the NO-independent stimulator of soluble guanylate cyclase, BAY 41–2272, significantly attenuated ONOO--induced apoptosis in a cGMP-dependent manner

Tumor Suppression and Sensitization to Taxol Induces Apoptosis of EIA in Breast Cancer Cells

DTIC Science & Technology

2005-06-01

participated in the regulation of apoptosis induced by ceramide, mistletoe lectin, and 4-hydroxynonenal, an aldehyde product of mem- brane lipid peroxidation... Mistletoe lectin induces apoptosis and telomerase inhibition in hu- man A253 cancer cells through dephosphorylation of Akt. Arch Pharm Res 2004; 27:68-76...participated subunit of protein phosphatase 2A [PP2A (PP2A/C)l enhanced the activity in the regulation of apoptosis induced by ceramide, mistletoe lectin, of

Uptake, accumulation and metabolization of the antidepressant fluoxetine by Mytilus galloprovincialis.

PubMed

Silva, Liliana J G; Martins, Margarida C; Pereira, André M P T; Meisel, Leonor M; Gonzalez-Rey, Maria; Bebianno, Maria João; Lino, Celeste M; Pena, Angelina

2016-06-01

Fluoxetine, a selective serotonin re-uptake inhibitor (SSRI) antidepressant, is among the most prescribed pharmaceutical active substances worldwide. This study aimed to assess its accumulation and metabolization in the mussel Mytillus galloprovincialis, considered an excellent sentinel species for traditional and emerging pollutants. Mussels were collected from Ria Formosa Lagoon, Portugal, and exposed to a nominal concentration of fluoxetine (75 ng L(-1)) for 15 days. Approximately 1 g of whole mussel soft tissues was extracted with acetonitrile:formic acid, loaded into an Oasis MCX cartridge, and fluoxetine analysed by liquid chromatography with tandem mass spectrometry (LC-MSn). After 3 days of exposure, fluoxetine was accumulated in 70% of the samples, with a mean of 2.53 ng g(-1) dry weight (d.w.) and norfluoxetine was only detected in one sample (10%), at 3.06 ng g(-1) d.w. After 7 days of exposure, the accumulation of fluoxetine and norfluoxetine increased up to 80 and 50% respectively, and their mean accumulated levels in mussel tissues were up to 4.43 and 2.85 ng g(-1) d.w., respectively. By the end of the exposure period (15 days), both compounds were detected in 100% of the samples (mean of 9.31 and 11.65 ng g(-1) d.w., respectively). Statistical analysis revealed significant accumulation differences between the 3rd and 15th day of exposure for fluoxetine, and between the 3rd and 7th against the 15th day of exposure for norfluoxetine. These results suggest that the fluoxetine accumulated in mussel tissues is likely to be metabolised into norfluoxetine with the increase of the time of exposure, giving evidence that at these realistic environmental concentrations, toxic effects of fluoxetine in mussel tissues may occur. Copyright © 2016 Elsevier Ltd. All rights reserved.

Biochemical and locomotor responses of Carcinus maenas exposed to the serotonin reuptake inhibitor fluoxetine.

PubMed

Mesquita, Sofia Raquel; Guilhermino, Lúcia; Guimarães, Laura

2011-10-01

The aim of this study was to assess the effects of the widely used anti-depressant fluoxetine on behaviour (locomotion), moulting, neuromuscular transmission, energy production and anti-oxidant defences' efficiency of the epibenthic crab Carcinus maenas. Crabs were individually exposed to fluoxetine concentrations for 7d. Effects on locomotion were assessed at the end of the exposure using an open field test adapted to C. maenas in the present study. Tissue samples were later collected to evaluate fluoxetine effects on physiological functions using the activity of key enzymes and other parameters as biomarkers, namely: N-acetyl-β-glucosaminidase (NAGase) in the epidermis (moulting) and the hepatopancreas; cholinesterases (ChE) in muscle (neuromuscular cholinergic transmission); NADP(+)-dependent isocitrate dehydrogenase (IDH) and lactate dehydrogenease (LDH) in muscle (energy production); glutathione S-transferases (GST) in hepatopancreas (biotransformation and oxidative stress system); glutathione reductase (GR), and glutathione peroxidade (GPx), total glutathione levels (TG) and lipid peroxidation levels in the hepatopancreas (anti-oxidant defences and oxidative damage). Because no information on C. maenas NAGase activity was previously available, its variation during the moult cycle was also investigated. The results showed that locomotion was significantly increased at fluoxetine concentrations equal or above 120 μg L⁻¹, with animals spending more time moving, walking longer distances than controls. Levels of NAGase activity were found to vary in relation to C. maenas moult cycle, but no alterations were observed after exposure to fluoxetine. Significant increases in the activity of ChE, GST and GR enzymes, and the levels of TG were found, with a lowest observed effect concentration (LOEC) of 120 μg L⁻¹. Effects on locomotion were significantly and positively correlated to those induced on ChE activity. The results raise concern when hypothesising

6-Gingerol induces autophagy to protect HUVECs survival from apoptosis.

PubMed

Wang, Shaopeng; Sun, Xiance; Jiang, Liping; Liu, Xiaofang; Chen, Min; Yao, Xiaofeng; Sun, Qinghua; Yang, Guang

2016-08-25

6-Gingerol, the major pharmacologically-active component of ginger, has the potential to prevent heart disease. However, the mechanisms are not well understood. In this study, the protective effect of 6-gingerol against hydrogen peroxide-induced apoptosis in human umbilical vein endothelial cells (HUVECs) was investigated. Apoptosis was detected by Hoechst 33342 and Flow cytometry analysis. To further elucidate the crosstalk between apoptosis and autophagy, we tested the expression of autophagy related proteins, LC3B, Bcl-2, Beclin1, AKT, p-AKT, mechanistic target of rapamycin (mTOR), and p-mTOR. Furthermore, mitochondrial membrane potential and the intracellular generation of reactive oxygen species (ROS) were also investigated. Our data revealed that 6-gingerol significantly reduced apoptosis by inducing autophagy. It has been demonstrated that 6-gingerol suppressed the phosphatidylinositol 3-kinase (PI3K)/AKT/mTOR signaling pathway, increased the expression of Beclin1 to promote autophagy, and increased Bcl-2 expression to inhibit apoptosis. In addition, the damage of mitochondrial was protected, and ROS level was decreased by 6-gingerol. These firmly indicate 6-gingerol has a strong protective ability against the apoptosis caused by oxidative stress in HUVECs, and the mechanism may relate to the induction of autophagy. Our data suggest 6-gingerol may be beneficial in the prevention of atherosclerosis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Radiation and stress-induced apoptosis: A role for Fas/Fas ligand interactions

PubMed Central

Reap, Elizabeth A.; Roof, Kevin; Maynor, Kenrick; Borrero, Michelle; Booker, Jessica; Cohen, Philip L.

1997-01-01

The lpr gene encodes a defective form of Fas, a cell surface protein that mediates apoptosis. This defect blocks apoptotic deletion of autoreactive T and B cells, leading to lymphoproliferation and lupus-like autoantibody production. The effects of the lpr Fas mutation on other kinds of physiologically relevant apoptosis are largely undocumented. To assess whether some of the apoptosis known to occur after ionizing radiation might be mediated by Fas/Fas ligand (FasL) interactions, we quantitated in vitro apoptosis by flow cytometry measurement of DNA content in splenic T and B cells from irradiated 5- to 8-month-old B6/lpr mice. Total apoptosis of both lpr and control cells was substantial after treatment; however there was a significant difference between B6 (73%) and lpr (25%) lymphocyte apoptosis. Thy1, CD4, CD8, and IgM cells from lpr showed much lower levels of apoptosis than control cells after irradiation. Apoptosis induced by heat shock was also impaired in lpr. The finding that γ-irradiation increased Fas expression on B6 cells and that irradiation-induced apoptosis could be blocked with a Fas–Fc fusion protein further supported the possible involvement of Fas in this form of apoptosis. Fas/FasL interactions may thus play an important role in identifying and eliminating damaged cells after γ-irradiation and other forms of injury. PMID:9159145

Protective Role of Mitochondrial Peroxiredoxin III against UVB-Induced Apoptosis of Epidermal Keratinocytes.

PubMed

Baek, Jin Young; Park, Sujin; Park, Jiyoung; Jang, Ji Yong; Wang, Su Bin; Kim, Sin Ri; Woo, Hyun Ae; Lim, Kyung Min; Chang, Tong-Shin

2017-06-01

UVB light induces generation of reactive oxygen species, ultimately leading to skin cell damage. Mitochondria are a major source of reactive oxygen species in UVB-irradiated skin cells, with increased levels of mitochondrial reactive oxygen species having been implicated in keratinocyte apoptosis. Peroxiredoxin III (PrxIII) is the most abundant and potent H 2 O 2 -removing enzyme in the mitochondria of most cell types. Here, the protective role of PrxIII against UVB-induced apoptosis of epidermal keratinocytes was investigated. Mitochondrial H 2 O 2 levels were differentiated from other types of ROS using mitochondria-specific fluorescent H 2 O 2 indicators. Upon UVB irradiation, PrxIII-knockdown HaCaT human keratinocytes and PrxIII-deficient (PrxIII -/- ) mouse primary keratinocytes exhibited enhanced accumulation of mitochondrial H 2 O 2 compared with PrxIII-expressing controls. Keratinocytes lacking PrxIII were subsequently sensitized to apoptosis through mitochondrial membrane potential loss, cardiolipin oxidation, cytochrome c release, and caspase activation. Increased UVB-induced epidermal tissue damage in PrxIII -/- mice was attributable to increased caspase-dependent keratinocyte apoptosis. Our findings show that mitochondrial H 2 O 2 is a key mediator in UVB-induced apoptosis of keratinocytes and that PrxIII plays a critical role in protecting epidermal keratinocytes against UVB-induced apoptosis through eliminating mitochondrial H 2 O 2 . These findings support the concept that reinforcing mitochondrial PrxIII defenses may help prevent UVB-induced skin damage such as inflammation, sunburn, and photoaging. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Thrombin-induced apoptosis in neurons through activation of c-Jun-N-terminal kinase.

PubMed

Bao, Lei; Zu, Jie; He, Qianqian; Zhao, Hui; Zhou, Su; Ye, Xinchun; Yang, Xinxin; Zan, Kun; Zhang, Zuohui; Shi, Hongjuan; Cui, Guiyun

2017-01-01

Studies have shown that thrombin activation played a central role in cell injuries associated with intracerebral hemorrhage (ICH). Here, our study investigated the cytotoxicity of thrombin on neurons, and determined the involvement of JNK pathways in thrombin-induced neuronal apoptosis. Primary cultured neurons were treated with different doses of thrombin. Some neurons were given either SP600125 or vehicle. LDH release assay and flow cytometry were used to measure neuronal apoptosis caused by thrombin. The activation of JNK and capases-3 were measured by Western blot. Our results showed large doses of thrombin that increased the LDH release, the level of cleaved caspase-3 and apoptosis rate of neurons. JNK was activated by thrombin in a time-dependent manner. Administration of SP600125 protects neurons from thrombin-induced apoptosis. These data indicate that the activation of JNK is crucial for thrombin-induced neuronal apoptosis, and inhibition of JNK may be a potential therapeutic target for ICH.

Phloretin induces apoptosis of human esophageal cancer via a mitochondria-dependent pathway.

PubMed

Duan, Hongtao; Wang, Ruixuan; Yan, Xiaolong; Liu, Honggang; Zhang, Yong; Mu, Deguang; Han, Jing; Li, Xiaofei

2017-12-01

2,4,6-trihydroxy-3-(4-hydroxyphenyl)-propiophenone (phloretin) is found in apple tree leaves and the Manchurian apricot, and is a potent compound that exhibits anti-inflammatory, antioxidant and antitumor activities. However, the effect of phloretin on esophageal cancer cells is not well-defined. The present study aimed to examine whether and how phloretin induced apoptosis in human esophageal cancer cells. EC-109 cells were cultured in Dulbecco's modified Eagle's medium and incubated with 60, 70, 80, 90 and 100 µg/ml phloretin for 6, 12, 24 and 48 h. Cell proliferation was measured by an MTT assay. Cell apoptosis rate was measured using flow cytometric analysis subsequent to propidium iodide (PI) staining. The protein expression levels were determined by western blot analysis. It was found that phloretin significantly decreased viable cell numbers in a dose- and time-dependent manner and induced apoptosis in EC-109 cells. Additionally, phloretin exhibited potent anticancer activity in vitro , as evidenced by the downregulation of the anti-apoptosis-associated molecule B-cell lymphoma 2 (bcl-2) and an increase in the levels of the apoptosis-associated molecules bcl-2-like protein 4 and tumor protein p53. Phloretin treatment also affected the expression of apoptotic protease activating factor-1, the protein product of the direct binding of the inhibitor of apoptosis protein with low PI to the X-linked inhibitor of apoptosis protein. The present results indicated that phloretin may inhibit EC-109 cell growth by inducing apoptosis, which may be mediated through a mitochondria-dependent pathway.

Aniline Induces Oxidative Stress and Apoptosis of Primary Cultured Hepatocytes.

PubMed

Wang, Yue; Gao, Hong; Na, Xiao-Lin; Dong, Shu-Ying; Dong, Hong-Wei; Yu, Jia; Jia, Li; Wu, Yong-Hui

2016-11-30

The toxicity and carcinogenicity of aniline in humans and animals have been well documented. However, the molecular mechanism involved in aniline-induced liver toxicity and carcinogenesis remains unclear. In our research, primary cultured hepatocytes were exposed to aniline (0, 1.25, 2.50, 5.0 and 10.0 μg/mL) for 24 h in the presence or absence of N -acetyl-l-cysteine (NAC). Levels of reactive oxygen species (ROS), malondialdehyde (MDA), and glutathione (GSH), activities of superoxide dismutase (SOD) and catalase (CAT), mitochondrial membrane potential, DNA damage, cell viability, and apoptosis were detected. Levels of ROS and MDA were significantly increased and levels of GSH and CAT, activity of SOD, and mitochondrial membrane potential in hepatocytes were significantly decreased by aniline compared with the negative control group. The tail moment and DNA content of the tail in exposed groups were significantly higher than those in the negative control group. Cell viability was reduced and apoptotic death was induced by aniline in a concentration-dependent manner. The phenomena of ROS generation, oxidative damage, loss of mitochondrial membrane potential, DNA damage and apoptosis could be prevented if ROS inhibitor NAC was added. ROS generation is involved in the loss of mitochondrial membrane potential and DNA injury, which may play a role in aniline-induced apoptosis in hepatocytes. Our study provides insight into the mechanism of aniline-induced toxicity and apoptosis of hepatocytes.

Aniline Induces Oxidative Stress and Apoptosis of Primary Cultured Hepatocytes

PubMed Central

Wang, Yue; Gao, Hong; Na, Xiao-Lin; Dong, Shu-Ying; Dong, Hong-Wei; Yu, Jia; Jia, Li; Wu, Yong-Hui

2016-01-01

The toxicity and carcinogenicity of aniline in humans and animals have been well documented. However, the molecular mechanism involved in aniline-induced liver toxicity and carcinogenesis remains unclear. In our research, primary cultured hepatocytes were exposed to aniline (0, 1.25, 2.50, 5.0 and 10.0 μg/mL) for 24 h in the presence or absence of N-acetyl-l-cysteine (NAC). Levels of reactive oxygen species (ROS), malondialdehyde (MDA), and glutathione (GSH), activities of superoxide dismutase (SOD) and catalase (CAT), mitochondrial membrane potential, DNA damage, cell viability, and apoptosis were detected. Levels of ROS and MDA were significantly increased and levels of GSH and CAT, activity of SOD, and mitochondrial membrane potential in hepatocytes were significantly decreased by aniline compared with the negative control group. The tail moment and DNA content of the tail in exposed groups were significantly higher than those in the negative control group. Cell viability was reduced and apoptotic death was induced by aniline in a concentration-dependent manner. The phenomena of ROS generation, oxidative damage, loss of mitochondrial membrane potential, DNA damage and apoptosis could be prevented if ROS inhibitor NAC was added. ROS generation is involved in the loss of mitochondrial membrane potential and DNA injury, which may play a role in aniline-induced apoptosis in hepatocytes. Our study provides insight into the mechanism of aniline-induced toxicity and apoptosis of hepatocytes. PMID:27916916

Involvement of Mst1 in tumor necrosis factor-{alpha}-induced apoptosis of endothelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ohtsubo, Hideki; Ichiki, Toshihiro; Imayama, Ikuyo

2008-03-07

Mammalian sterile 20-kinase 1 (Mst1), a member of the sterile-20 family protein kinase, plays an important role in the induction of apoptosis. However, little is know about the physiological activator of Mst1 and the role of Mst1 in endothelial cells (ECs). We examined whether Mst1 is involved in the tumor necrosis factor (TNF)-{alpha}-induced apoptosis of ECs. Western blot analysis revealed that TNF-{alpha} induced activation of caspase 3 and Mst1 in a time- and dose-dependent manner. TNF-{alpha}-induced Mst1 activation is almost completely prevented by pretreatment with Z-DEVD-FMK, a caspase 3 inhibitor. Nuclear staining with Hoechst 33258 and fluorescence-activated cell sorting ofmore » propidium iodide-stained cells showed that TNF-{alpha} induced apoptosis of EC. Diphenyleneiodonium, an inhibitor of NADPH oxidase, and N-acetylcysteine, a potent antioxidant, also inhibited TNF-{alpha}-induced activation of Mst1 and caspase 3, as well as apoptosis. Knockdown of Mst1 expression by short interfering RNA attenuated TNF-{alpha}-induced apoptosis but not cleavage of caspase 3. These results suggest that Mst1 plays an important role in the induction of TNF-{alpha}-induced apoptosis of EC. However, positive feedback mechanism between Mst1 and caspase 3, which was shown in the previous studies, was not observed. Inhibition of Mst1 function may be beneficial for maintaining the endothelial integrity and inhibition of atherogenesis.« less

Molecular Mechanisms of Particle Ration Induced Apoptosis in Lymphocyte

NASA Astrophysics Data System (ADS)

Shi, Yufang

Space radiation, composed of high-energy charged nuclei (HZE particles) and protons, has been previously shown to severely impact immune homeostasis in mice. To determine the molecular mechanisms that mediate acute lymphocyte depletion following exposure to HZE particle radiation mice were exposed to particle radiation beams at Brookhaven National Laboratory. We found that mice given whole body 5 6Fe particle irradiation (1GeV /n) had dose-dependent losses in total lymphocyte numbers in the spleen and thymus (using 200, 100 and 50 cGy), with thymocytes being more sensitive than splenocytes. All phenotypic subsets were reduced in number. In general, T cells and B cells were equally sensitive, while CD8+ T cells were more senstive than CD4+ T cells. In the thymus, immature CD4+CD8+ double-positive thymocytes were exquisitely sensitive to radiation-induced losses, single-positive CD4 or CD8 cells were less sensitive, and the least mature double negative cells were resistant. Irradiation of mice deficient in genes encoding essential apoptosis-inducing proteins revealed that the mechanism of lymphocyte depletion is independent of Fas ligand and TRAIL (TNF-ralated apoptosis-inducing ligand), in contrast to γ-radiation-induced lymphocyte losses which require the Fas-FasL pathway. Using inhibitors in vitro, lymphocyte apoptosis induced by HZE particle radiation was found to be caspase dependent, and not involve nitric oxide or oxygen free radicals.

Acid Sphingomyelinase Mediates Oxidized-LDL Induced Apoptosis in Macrophage via Endoplasmic Reticulum Stress

PubMed Central

Zhao, Min; Pan, Wei; Shi, Rui-zheng; Bai, Yong-ping; You, Bo-yang; Zhang, Kai; Fu, Qiong-mei; Schuchman, Edward H.

2016-01-01

Aim: Macrophage apoptosis is a vital event in advanced atherosclerosis, and oxidized low-density lipoprotein (ox-LDL) is a major contributor to this process. Acid sphingomyelinase (ASM) and ceramide are also involved in the induction of apoptosis, particularly in macrophages. Our current study focuses on ASM and investigates its role in ox-LDL-induced macrophage apoptosis. Methods: Human THP-1 and mouse peritoneal macrophages were cultured in vitro and treated with ox-LDL. ASM activity and ceramide levels were quantified using ultra performance liquid chromatography. Protein and mRNA levels were analyzed using Western blot analysis and quantitative realtime PCR, respectively. Cell apoptosis was determined using Hoechst staining and flow cytometry. Results: Ox-LDL-induced macrophage apoptosis was triggered by profound endoplasmic reticulum (ER) stress, leading to an upregulation of ASM activity and ceramide levels at an early stage. ASM was inhibited by siRNA or desipramine (DES), and/or ceramide was degraded by recombinant acid ceramidase (AC). These events attenuated the effect of ox-LDL on ER stress. In contrast, recombinant ASM upregulated ceramide and ER stress. ASM siRNA, DES, recombinant AC, and ER stress inhibitor 4-phenylbutyric acid were blocked by elevated levels of C/EBP homologous protein (CHOP); ox-LDL induced elevated levels of CHOP. These events attenuated macrophage apoptosis. Conclusion: These results indicate that ASM/ceramide signaling pathway is involved in ox-LDL-induced macrophage apoptosis via ER stress pathway. PMID:26923251

Oxidative stress-driven mechanisms of nordihydroguaiaretic acid-induced apoptosis in FL5.12 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deshpande, Vaidehee S.; Kehrer, James P.

2006-08-01

Nordihydroguaiaretic acid (NDGA), a general lipoxygenase (LOX) enzyme inhibitor, induces apoptosis independently of its activity as a LOX inhibitor in murine pro-B lymphocytes (FL.12 cells) by a mechanism that is still not fully understood. Glutathione depletion, oxidative processes and mitochondrial depolarization appear to contribute to the apoptosis induced by NDGA. The current data demonstrate that NDGA (20 {mu}M)-induced apoptosis in FL5.12 cells is partially protected by N-acetylcysteine (NAC) (10 mM) and dithiothreitol (DTT) (500 {mu}M) pretreatment, confirming a role for oxidative processes. In addition, the treatment of FL5.12 cells with NDGA led to an increase in phosphorylation and activation ofmore » the MAP kinases ERK, JNK and p38. Although pretreatment with ERK inhibitors (PD98059 or U0126) abolished ERK phosphorylation in response to NDGA, neither inhibitor had any effect on NDGA-induced apoptosis. SP600125, a JNK inhibitor, did not have any effect on NDGA-induced phosphorylation of JNK nor apoptosis. Pretreatment with the p38 inhibitor SB202190 attenuated NDGA-induced apoptosis by 30% and also abolished p38 phosphorylation, compared to NDGA treatment alone. NAC, but not DTT, also decreased the phosphorylation of p38 and JNK supporting a role for oxidative processes in activating these kinases. Neither NAC nor DTT blocked the phosphorylation of ERK suggesting that this activation is not related to oxidative stress. The release of cytochrome c and activation of caspase-3 induced by NDGA were inhibited by NAC. SB202190 slightly attenuated caspase-3 activation and had no effect on the release of cytochrome c. These data suggest that several independent mechanisms, including oxidative reactions, activation of p38 kinase and cytochrome c release contribute to NDGA-induced apoptosis.« less

Fluoxetine induces lean phenotype in rat by increasing the brown/white adipose tissue ratio and UCP1 expression.

PubMed

da Silva, A I; Braz, G R F; Pedroza, A A; Nascimento, L; Freitas, C M; Ferreira, D J S; Manhães de Castro, R; Lagranha, C J

2015-08-01

The serotonergic system plays a crucial role in the energy balance regulation. Energy balance is mediated by food intake and caloric expenditure. Thus, the present study investigated the mechanisms that might be associated with fluoxetine treatment-induced weight reduction. Wistar male rat pups received daily injections with subcutaneous fluoxetine (Fx-group) or vehicle solution (Ct-group) from day 1 until 21 days of age. Several analyses were conducted to verify the involvement of mitochondria in weight reduction. We found that body weight in the Fx-group was lower compared to control. In association to lower fat mass in the Fx-group (25%). Neither neonatal caloric intake nor food intake reveals significant differences. Evaluating caloric expenditure (locomotor activity and temperature after stimulus), we did not observe differences in locomotor activity. However, we observed that the Fx group had a higher capacity to maintain body temperature in a cold environment compared with the Ct-group. Since brown adipose tissue-(BAT) is specialized for heat production and the rate of heat production is related to mitochondrial function, we found that Fx-treatment increases respiration by 36%, although after addition of GDP respiration returned to Ct-levels. Examining ROS production we observe that Fx-group produced less ROS than control group. Evaluating uncoupling protein (UCP) expression we found that Fx-treatment increases the expression by 23%. Taken together, our results suggest that modulation of serotonin system results in positive modulation of UCP and mitochondrial bioenergetics in brown fat tissue.

Infrasound sensitizes human glioblastoma cells to cisplatin-induced apoptosis.

PubMed

Rachlin, Kenneth; Moore, Dan H; Yount, Garret

2013-11-01

The development of nontoxic agents that can selectively enhance the cytotoxicity of chemotherapy is an important aim in oncology. This study evaluates the ability of infrasound exposure to sensitize glioblastoma cells to cisplatin-induced apoptosis. The infrasound was delivered using a device designed to replicate the unique infrasound emissions measured during external Qigong treatments. Human glioblastoma cell lines harboring wild-type p53 (U87) or mutant p53 (U251, SF210, and SF188) were treated in culture with cisplatin, infrasound emissions, or the combination of the 2 agents. Induction of apoptosis was quantified after 24 hours by flow cytometry following annexin V/propidium iodide staining. Infrasound emissions alone, delivered at moderate levels (~10 mPa) with dynamic frequency content (7-13 Hz), did not induce apoptosis, yet combining infrasound with cisplatin augmented the induction of apoptosis by cisplatin in all the 4 cell lines (P < .05). Increased cellular uptake of the fluorophore calcein associated with infrasound exposure was quantified by fluorescence microscopy as well as flow cytometry, demonstrating increased cell membrane permeability. The 4 cell lines differed in the degree to which infrasound exposure increased calcein uptake, and these differences were predictive of the extent to which infrasound enhanced cisplatin-induced apoptosis. When exposed to specific frequencies, membrane permeabilization also appeared to be differentially responsive for each cell line, suggesting the potential for selective targeting of tissue types using isolated infrasonic frequencies. Additionally, the pressure amplitudes used in this study were several orders of magnitude less than those used in similar studies involving ultrasound and shock waves. The results of this study provide support for using infrasound to enhance the chemotherapeutic effects of cisplatin in a clinical setting.

Convergence of glycogen synthase kinase 3β and GR signaling in response to fluoxetine treatment in chronically stressed female and male rats.

PubMed

Mitic, Milos; Brkic, Zeljka; Lukic, Iva; Adzic, Miroslav

2017-08-30

Accumulating evidence strongly suggest that impaired glucocorticoid receptor (GR) signaling is involved in stress-related mood disorders, and nominate GR as a potential target for antidepressants (ADs). It is known that different classes of ADs affects the GR action via modifying its phosphorylation, while the mechanism through which ADs alter GR phosphorylation targeted by GSK3β, a kinase modulated via serotonin neurotransmission, are unclear. On this basis, we investigated whether GSK3β-GR signaling could be a convergence point of fluoxetine action on brain function and behavior, by examining its effect on GSK3β targeted-GR phosphorylation on threonine 171 (pGR171), and expression of GR-regulated genes in the hippocampus of female and male rats exposed to chronic isolation stress. Stress induced sex-specific GSK3β-targeted phosphorylation of pGR171 in the nucleus of the hippocampus of stressed animals. Namely, while in females stress triggered coupled action of GSK3β-pGR171 signaling, in males changes in pGR171 levels did not correspond to GSK3β activity. On the other hand, fluoxetine managed to up-regulate this pathway in sex-unbiased manner. Furthermore, fluoxetine reverted stress-induced changes in most of the analyzed genes in males, CRH, 5-HT1a and p11, while in females its effect was limited to CRH. These data further suggest that pGR171 signaling affects cellular localization of GR in response to chronic stress and fluoxetine in both sexes. Collectively, our results describe a novel convergence point between GR signaling and GSK3β pathway in rat hippocampus in response to stress and fluoxetine in both sexes and its involvement in fluoxetine-regulated brain function in males. Copyright © 2017 Elsevier B.V. All rights reserved.

Lack of efficacy for fluoxetine in PTSD: a placebo controlled trial in combat veterans.

PubMed

Hertzberg, M A; Feldman, M E; Beckham, J C; Kudler, H S; Davidson, J R

2000-06-01

Fluoxetine and placebo were studied in a population of combat veterans with severe, chronic PTSD. Twelve male veterans with PTSD were enrolled in a 12 week double-blind evaluation of fluoxetine and placebo. Mean fluoxetine dose at endpoint (week 12) was 48 mg/day with a range of 10 mg to 60 mg. One fluoxetine patient responded (17%) and two of the six placebo patients responded (33%). Fluoxetine patients did not show a greater response than placebo patients in this small sample of male combat veterans with severe, chronic PTSD. Fluoxetine has displayed an efficacious response in controlled studies of patients with PTSD who were predominantly female, suffered civilian (noncombat) traumas, and were overall experiencing less severe PTSD. The reasons for the low response rate to fluoxetine in our study is unknown and will await further study examining variables other than symptoms that might influence outcome, such as gender, comorbidity, prior treatment history, trauma type, severity and chronicity.

Mechanism of Siglec-8-induced human eosinophil apoptosis: role of caspases and mitochondrial injury.

PubMed

Nutku, Esra; Hudson, Sherry A; Bochner, Bruce S

2005-10-28

Sialic acid binding immunoglobulin like lectin (Siglec)-8 crosslinking with specific antibodies causes human eosinophil apoptosis. Mechanisms by which Siglec-8 crosslinking induces apoptosis are not known. Peripheral blood eosinophils were examined for caspase, mitochondria and reactive oxygen species (ROS) involvement after incubating the cells with anti-Siglec-8 crosslinking Abs or control Abs, in the presence or absence of selective inhibitors. Siglec-8 crosslinking induced rapid cleavage of caspase-3, caspase-8, and caspase-9 in eosinophils. Selective caspase-8 and/or caspase-9 inhibitors inhibited this apoptosis. Siglec-8 crosslinking on eosinophils increased dissipation of mitochondrial membrane potential upstream of caspase activation. Rotenone and antimycin, inhibitors of mitochondrial respiratory chain components, completely inhibited apoptosis. Additional experiments with an inhibitor of ROS, diphenyleneiodonium, demonstrated that ROS was also essential for Siglec-8-mediated apoptosis and preceded Siglec-8-mediated mitochondrial dissipation. These experiments show that Siglec-8-induced apoptosis occurs through the sequential production of ROS, followed by induction of mitochondrial injury and caspase cleavage.

Time course of Paclitaxel-induced apoptosis in an experimental model of virus-induced breast cancer.

PubMed

Erba, Paola A; Manfredi, Chiara; Lazzeri, Elena; Minichilli, Fabrizio; Pauwels, Ernest K J; Sbrana, Alberto; Strauss, H William; Mariani, Giuliano

2010-05-01

Early assessment of the efficacy of treatment is important in patients with breast cancer, whose routine adjuvant regimen frequently includes chemotherapy. Irrespective of the exact mechanisms involved in induction, the common early phenotypic marker of apoptosis is the expression on the outer cell membrane surface of phosphatidylserine, which avidly binds annexin V. (99m)Tc-labeled annexin V has been proposed for in vivo scintigraphic detection of apoptosis, albeit with contradicting results. This study was performed to define the time course of apoptosis induced by the chemotherapeutic agent paclitaxel in a model of virus-induced murine breast cancer. The RIII virus induces an estrogen-dependent, slow-growing breast cancer; BALB-c/cRIII female mice with breast tumors averaging 10 mm were studied, both in baseline conditions and at various times after the intravenous administration of paclitaxel (equivalent to a human dose of 20 mg/70 kg of body weight). The biodistribution of (99m)Tc-annexin V was evaluated at baseline and then at 1, 3, 6, and 24 h after paclitaxel administration. Apoptotic and antiapoptotic markers were also evaluated in tumor samples obtained at the same time points: DNA breaks (terminal deoxynucleotidyl transferase biotin-dUTP nick-end labeling [TUNEL]), active caspase-3, apoptosis-inducing factor, and Bcl-2 protein. Baseline uptake of (99m)Tc-annexin V in breast tumors was about 2-fold higher than the uptake in normal breast tissue (demonstrating some ongoing apoptosis); tracer uptake increased at 1 and 3 h after paclitaxel administration (to almost double the baseline value) and then declined to levels even lower than baseline. Although no activation of the apoptosis-inducing factor mechanism was detected, a peak in TUNEL-positive tumor cells was reached 3 h after paclitaxel administration (to more than 6-fold the baseline level). The antiapoptotic marker Bcl-2 exhibited a biphasic pattern, with a maximum drop at 3 h, followed by return

Fluoxetine Dose and Administration Method Differentially Affect Hippocampal Plasticity in Adult Female Rats

PubMed Central

Pawluski, Jodi L.; van Donkelaar, Eva; Abrams, Zipporah; Steinbusch, Harry W. M.; Charlier, Thierry D.

2014-01-01

Selective serotonin reuptake inhibitor medications are one of the most common treatments for mood disorders. In humans, these medications are taken orally, usually once per day. Unfortunately, administration of antidepressant medications in rodent models is often through injection, oral gavage, or minipump implant, all relatively stressful procedures. The aim of the present study was to investigate how administration of the commonly used SSRI, fluoxetine, via a wafer cookie, compares to fluoxetine administration using an osmotic minipump, with regards to serum drug levels and hippocampal plasticity. For this experiment, adult female Sprague-Dawley rats were divided over the two administration methods: (1) cookie and (2) osmotic minipump and three fluoxetine treatment doses: 0, 5, or 10 mg/kg/day. Results show that a fluoxetine dose of 5 mg/kg/day, but not 10 mg/kg/day, results in comparable serum levels of fluoxetine and its active metabolite norfluoxetine between the two administration methods. Furthermore, minipump administration of fluoxetine resulted in higher levels of cell proliferation in the granule cell layer (GCL) at a 5 mg dose compared to a 10 mg dose. Synaptophysin expression in the GCL, but not CA3, was significantly lower after fluoxetine treatment, regardless of administration method. These data suggest that the administration method and dose of fluoxetine can differentially affect hippocampal plasticity in the adult female rat. PMID:24757568

Fluoxetine improves functional work capacity in women with premenstrual dysphoric disorder.

PubMed

Steiner, M; Brown, E; Trzepacz, P; Dillon, J; Berger, C; Carter, D; Reid, R; Stewart, D

2003-02-01

Interference with social and occupational functioning is a key criterion for premenstrual dysphoric disorder (PMDD) and distinguishes it from the less severe premenstrual syndrome (PMS). We conducted a post hoc analysis of the results of a previously reported study evaluating the efficacy of fluoxetine in the management of PMDD, to determine the extent to which women with PMDD perceived impairment in their functional work capacity during the luteal phase of their menstrual cycle. The effects of two doses of fluoxetine vs placebo in alleviating PMDD symptoms and restoring normal work capacity during this period were assessed. We measured baseline follicular vs luteal phase presence of 8 patient-rated functional work capacity-related symptoms on the Premenstrual Tension Scale-Self Rated in 320 women who met diagnostic criteria for late luteal phase dysphoric disorder, now known as PMDD. Women were then randomized to double-blind treatment with either fluoxetine 20 mg/d, fluoxetine 60 mg/d, or placebo daily for 6 menstrual cycles. All 8 work capacity-related symptoms were more likely to be present in the baseline luteal phase than in the baseline follicular phase. A statistically significant improvement from baseline to the average treatment score for the work capacity subscale was detected for both fluoxetine groups compared to the placebo group. This beneficial response to fluoxetine was evident by the first cycle of treatment. Our results demonstrate that fluoxetine at a relatively low dose of 20 mg/d quickly reduced symptoms that negatively affect work capacity and was well tolerated.

The C. elegans TIA-1/TIAR homolog TIAR-1 is required to induce germ cell apoptosis.

PubMed

Silva-García, Carlos Giovanni; Estela Navarro, Rosa

2013-10-01

In Caenorhabditis elegans, physiological germ cell apoptosis eliminates more than half of the cells in the hermaphrodite gonad to support gamete quality and germline homeostasis by a still unidentified mechanism. External factors can also affect germ cell apoptosis. The BH3-only protein EGL-1 induces germ cell apoptosis when animals are exposed to pathogens or agents that produce DNA damage. DNA damage-induced apoptosis also requires the nematode p53 homolog CEP-1. Previously, we found that heat shock, oxidative, and osmotic stresses induce germ cell apoptosis through an EGL-1 and CEP-1 independent mechanism that requires the MAPKK pathway. However, we observed that starvation increases germ cell apoptosis by an unknown pathway. Searching for proteins that participate in stress-induced apoptosis, we found the RNA-binding protein TIAR-1 (a homolog of the mammalian TIA-1/TIAR family of proteins). Here, we show that TIAR-1 in C. elegans is required to induce apoptosis in the germline under several conditions. We also show that TIAR-1 acts downstream of CED-9 (a BCL2 homolog) to induce apoptosis under stress conditions, and apparently does not seem to regulate ced-4 or ced-3 mRNAs accumulation directly. TIAR-1 is expressed ubiquitously in the cytoplasm of the soma as well as the germline, where it sometimes associates with P granules. We show that animals lacking TIAR-1 expression are temperature sensitive sterile due to oogenesis and spermatogenesis defects. Our work shows that TIAR-1 is required for proper germline function and demonstrates that this protein is important to induce germ cell apoptosis under several conditions. Copyright © 2013 Wiley Periodicals, Inc.

Regulation of singlet oxygen-induced apoptosis by cytosolic NADP+-dependent isocitrate dehydrogenase.

PubMed

Kim, Sun Yee; Lee, Su Min; Tak, Jean Kyoung; Choi, Kyeong Sook; Kwon, Taeg Kyu; Park, Jeen-Woo

2007-08-01

Singlet oxygen is a highly reactive form of molecular oxygen that may harm living systems by oxidizing critical cellular macromolecules and it also promotes deleterious processes such as cell death. Recently, we demonstrated that the control of redox balance and the cellular defense against oxidative damage are the primary functions of cytosolic NADP(+)-dependent isocitrate dehydrogenase (IDPc) through supplying NADPH for antioxidant systems. In this report, we demonstrate that modulation of IDPc activity in HL-60 cells regulates singlet oxygen-induced apoptosis. When we examined the protective role of IDPc against singlet oxygen-induced apoptosis with HL-60 cells transfected with the cDNA for mouse IDPc in sense and antisense orientations, a clear inverse relationship was observed between the amount of IDPc expressed in target cells and their susceptibility to apoptosis. The results suggest that IDPc plays an important protective role in apoptosis of HL-60 cells induced by singlet oxygen.

Apoptotic cells can induce non-autonomous apoptosis through the TNF pathway

PubMed Central

Pérez-Garijo, Ainhoa; Fuchs, Yaron; Steller, Hermann

2013-01-01

Apoptotic cells can produce signals to instruct cells in their local environment, including ones that stimulate engulfment and proliferation. We identified a novel mode of communication by which apoptotic cells induce additional apoptosis in the same tissue. Strong induction of apoptosis in one compartment of the Drosophila wing disc causes apoptosis of cells in the other compartment, indicating that dying cells can release long-range death factors. We identified Eiger, the Drosophila tumor necrosis factor (TNF) homolog, as the signal responsible for apoptosis-induced apoptosis (AiA). Eiger is produced in apoptotic cells and, through activation of the c-Jun N-terminal kinase (JNK) pathway, is able to propagate the initial apoptotic stimulus. We also show that during coordinated cell death of hair follicle cells in mice, TNF-α is expressed in apoptotic cells and is required for normal cell death. AiA provides a mechanism to explain cohort behavior of dying cells that is seen both in normal development and under pathological conditions. DOI: http://dx.doi.org/10.7554/eLife.01004.001 PMID:24066226

A microtubule inhibitor, ABT-751, induces autophagy and delays apoptosis in Huh-7 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wei, Ren-Jie

The objective was to investigate the upstream mechanisms of apoptosis which were triggered by a novel anti-microtubule drug, ABT-751, in hepatocellular carcinoma-derived Huh-7 cells. Effects of ABT-751 were evaluated by immunocytochemistry, flow cytometric, alkaline comet, soft agar, immunoblotting, CytoID, green fluorescent protein-microtubule associated protein 1 light chain 3 beta detection, plasmid transfection, nuclear/cytosol fractionation, coimmunoprecipitation, quantitative reverse transcription-polymerase chain reaction, small-hairpin RNA interference and mitochondria/cytosol fractionation assays. Results showed that ABT-751 caused dysregulation of microtubule, collapse of mitochondrial membrane potential, generation of reactive oxygen species (ROS), DNA damage, G{sub 2}/M cell cycle arrest, inhibition of anchorage-independent cell growth and apoptosismore » in Huh-7 cells. ABT-751 also induced early autophagy via upregulation of nuclear TP53 and downregulation of the AKT serine/threonine kinase (AKT)/mechanistic target of rapamycin (MTOR) pathway. Through modulation of the expression levels of DNA damage checkpoint proteins and G{sub 2}/M cell cycle regulators, ABT-751 induced G{sub 2}/M cell cycle arrest. Subsequently, ABT-751 triggered apoptosis with marked downregulation of B-cell CLL/lymphoma 2, upregulation of mitochondrial BCL2 antagonist/killer 1 and BCL2 like 11 protein levels, and cleavages of caspase 8 (CASP8), CASP9, CASP3 and DNA fragmentation factor subunit alpha proteins. Suppression of ROS significantly decreased ABT-751-induced autophagic and apoptotic cells. Pharmacological inhibition of autophagy significantly increased the percentages of ABT-751-induced apoptotic cells. The autophagy induced by ABT-751 plays a protective role to postpone apoptosis by exerting adaptive responses following microtubule damage, ROS and/or impaired mitochondria. - Highlights: • An anti-microtubule agent, ABT-751, induces autophagy and apoptosis in Huh-7

Downregulation of X-linked inhibitor of apoptosis protein by '7-Benzylidenenaltrexone maleate' sensitizes pancreatic cancer cells to TRAIL-induced apoptosis.

PubMed

Kim, So Young; Park, Sojung; Yoo, SeonA; Rho, Jin Kyung; Jun, Eun Sung; Chang, Suhwan; Kim, Kyung Kon; Kim, Song Cheol; Kim, Inki

2017-09-22

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a potential biological anticancer agent. However, a wide range of human primary cancers, including pancreatic cancer, display resistance to apoptosis induction by TRAIL. Therefore, this resistance needs to be overcome to allow TRAIL to be successfully used in cancer therapy. In this study, we performed a compound screen to isolate TRAIL sensitizers and found that one of the identified compounds, 7-benzylidenenaltrexone maleate (BNTX), sensitized pancreatic cancer cells to TRAIL-induced apoptotic cell death. The combination of BNTX with TRAIL promoted the release of cytochrome c from mitochondria into cytosol with caspase activation and a resulting increase in annexin V-stained cells. From a mechanistic perspective, we found that BNTX downregulated X-linked inhibitor of apoptosis protein (XIAP) expression when used in combination with TRAIL, and found that TRAIL-induced apoptosis was augmented by siRNA-mediated knockdown of XIAP. We further demonstrated that BNTX promoted the ubiquitin/proteasome-dependent degradation of XIAP protein via protein kinase C (PKC) alpha/AKT pathway inhibition. Moreover, combined treatment by BNTX with TRAIL suppressed growth of pancreatic tumor xenograft of animal model. Therefore, we suggest that inhibitor of apoptosis protein-mediated resistance of pancreatic cancer cells to anticancer therapeutics can be overcome by inhibiting the PKCα/AKT pathway.

Notch1 Signaling Sensitizes Tumor Necrosis Factor-related Apoptosis-inducing Ligand-induced Apoptosis in Human Hepatocellular Carcinoma Cells by Inhibiting Akt/Hdm2-mediated p53 Degradation and Up-regulating p53-dependent DR5 Expression*

PubMed Central

Wang, Chunmei; Qi, Runzi; Li, Nan; Wang, Zhengxin; An, Huazhang; Zhang, Qinghua; Yu, Yizhi; Cao, Xuetao

2009-01-01

Notch signaling plays a critical role in regulating cell proliferation, differentiation, and apoptosis. Our previous study showed that overexpression of Notch1 could inhibit human hepatocellular carcinoma (HCC) cell growth by arresting the cell cycle and inducing apoptosis. HCC cells are resistant to apoptotic induction by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), so new therapeutic approaches have been explored to sensitize HCC cells to TRAIL-induced apoptosis. We are wondering whether and how Notch1 signaling can enhance the sensitivity of HCC cells to TRAIL-induced apoptosis. In this study, we found that overexpression of ICN, the constitutive activated form of Notch1, up-regulated p53 protein expression in HCC cells by inhibiting proteasome degradation. p53 up-regulation was further observed in human primary hepatocellular carcinoma cells after activation of Notch signaling. Inhibition of the Akt/Hdm2 pathway by Notch1 signaling was responsible for the suppression of p53 proteasomal degradation, thus contributing to the Notch1 signaling-mediated up-regulation of p53 expression. Accordingly, Notch1 signaling could make HCC cells more sensitive to TRAIL-induced apoptosis, whereas Notch1 signaling lost the synergistic promotion of TRAIL-induced apoptosis in p53-silenced HepG2 HCC cells and p53-defective Hep3B HCC cells. The data suggest that enhancement of TRAIL-induced apoptosis by Notch1 signaling is dependent upon p53 up-regulation. Furthermore, Notch1 signaling could enhance DR5 expression in a p53-dependent manner. Taken together, Notch1 signaling sensitizes TRAIL-induced apoptosis in HCC cells by inhibiting Akt/Hdm2-mediated p53 degradation and up-regulating p53-dependent DR5 expression. Thus, our results suggest that activation of Notch1 signaling may be a promising approach to improve the therapeutic efficacy of TRAIL-resistant HCC. PMID:19376776

Escin-induced DNA damage promotes escin-induced apoptosis in human colorectal cancer cells via p62 regulation of the ATM/γH2AX pathway.

PubMed

Wang, Zhong; Chen, Qiang; Li, Bin; Xie, Jia-Ming; Yang, Xiao-Dong; Zhao, Kui; Wu, Yong; Ye, Zhen-Yu; Chen, Zheng-Rong; Qin, Zheng-Hong; Xing, Chun-Gen

2018-05-31

Escin, a triterpene saponin isolated from horse chestnut seed, has been used to treat encephaledema, tissue swelling and chronic venous insufficiency. Recent studies show that escin induces cell cycle arrest, tumor proliferation inhibition and tumor cell apoptosis. But the relationship between escin-induced DNA damage and cell apoptosis in tumor cells remains unclear. In this study, we investigated whether and how escin-induced DNA damage contributed to escin-induced apoptosis in human colorectal cancer cells. Escin (5-80 μg/mL) dose-dependently inhibited the cell viability and colony formation in HCT116 and HCT8 cells. Escin treatment induced DNA damage, leading to p-ATM and γH2AX upregulation. Meanwhile, escin treatment increased the expression of p62, an adaptor protein, which played a crucial role in controlling cell survival and tumorigenesis, and had a protective effect against escin-induced DNA damage: knockdown of p62 apparently enhanced escin-induced DNA damage, whereas overexpression of p62 reduced escin-induced DNA damage. In addition, escin treatment induced concentration- and time-dependent apoptosis. Similarly, knockdown of p62 significantly increased escin-induced apoptosis in vitro and produced en escin-like antitumor effect in vivo. Overexpression of p62 decreased the rate of apoptosis. Further studies revealed that the functions of p62 in escin-induced DNA damage were associated with escin-induced apoptosis, and p62 knockdown combined with the ATM inhibitor KU55933 augmented escin-induced DNA damage and further increased escin-induced apoptosis. In conclusion, our results demonstrate that p62 regulates ATM/γH2AX pathway-mediated escin-induced DNA damage and apoptosis.

Deficiency in methionine, tryptophan, isoleucine, or choline induces apoptosis in cultured cells.

PubMed

Yen, Chi-Liang E; Mar, Mei-Heng; Craciunescu, Corneliu N; Edwards, Lloyd J; Zeisel, Steven H

2002-07-01

Cells in culture die by apoptosis when deprived of the essential nutrient choline. We now report that cells (both proliferating PC12 cells and postmitotic neurons isolated from fetal rat brains) undergo apoptosis when deprived of other individual essential nutrients (methionine, tryptophan or isoleucine). In PC12 cells, deficiencies of each nutrient independently led to ceramide accumulation and to caspase activation, both recognized signals of several apoptotic pathways. A similar profile of caspases was activated in PC12 cells deprived of choline, methionine, tryptophan or isoleucine. More than one caspase was involved and these caspases appeared to transmit parallel signals for apoptosis induction because only broad-spectrum caspase inhibitors, but not inhibitors for specific individual caspases inhibited apoptosis in choline- or methionine-deprived cells. The induction of these caspase-dependent apoptosis pathways likely did not involve the same upstream signals. Choline deficiency perturbed choline metabolism but did not affect protein synthesis, whereas amino acid deficiencies inhibited protein synthesis but did not perturb choline metabolism. In addition, a subclone of PC12 cells that was resistant to choline deficiency-induced apoptosis was not resistant to tryptophan deficiency-induced apoptosis. These observations suggest that deficiency of each studied nutrient activates different pathways for signaling apoptosis that ultimately converge on a common execution pathway.

Bromelain-induced apoptosis in GI-101A breast cancer cells.

PubMed

Dhandayuthapani, Sivanesan; Perez, Honey Diaz; Paroulek, Alexandra; Chinnakkannu, Panneerselvam; Kandalam, Umadevi; Jaffe, Mark; Rathinavelu, Appu

2012-04-01

Bromelain is a proteolytic enzyme extracted from the stems and the immature fruits of pineapple that was found to be antitumorigenic in different in vitro models. Bromelain has been reported to promote apoptosis, particularly in breast cancer cells, with the up-regulation of c-Jun N-terminal kinase and p38 kinase. Our study was designed to determine if bromelain could induce apoptosis in GI-101A breast cancer cells. GI-101A cells were treated with increasing concentrations of bromelain for 24 hours. The effect of bromelain for inducing cell death via activation of the apoptosis mechanism in GI-101A cells was further determined by using caspase-9 and caspase-3 assays along with the M30-Apoptosense assay to measure cytokeratin 18 (CK18) levels in the cytoplasm of the cultured cancer cells. A dose-dependent increase in the activities of caspase-9 and caspase-3 coinciding with elevation of CK18 levels was found in bromelain-treated cells compared with control cells. Furthermore, the apoptosis induction by bromelain was confirmed by DNA fragmentation analysis and 4,6'-diamino-2-phenylindole dihydrochloride fluorescence staining of the nucleus. Our results indicate an increase in apoptosis-related cell death in breast cancer cells with increasing concentrations of bromelain.

Drosophila MOF regulates DIAP1 and induces apoptosis in a JNK dependent pathway.

PubMed

Pushpavalli, Sreerangam N C V L; Sarkar, Arpita; Ramaiah, M Janaki; Koteswara Rao, G; Bag, Indira; Bhadra, Utpal; Pal-Bhadra, Manika

2016-03-01

Histone modulations have been implicated in various cellular and developmental processes where in Drosophila Mof is involved in acetylation of H4K16. Reduction in the size of larval imaginal discs is observed in the null mutants of mof with increased apoptosis. Deficiency involving Hid, Reaper and Grim [H99] alleviated mof (RNAi) induced apoptosis in the eye discs. mof (RNAi) induced apoptosis leads to activation of caspases which is suppressed by over expression of caspase inhibitors like P35 and Diap1 clearly depicting the role of caspases in programmed cell death. Also apoptosis induced by knockdown of mof is rescued by JNK mutants of bsk and tak1 indicating the role of JNK in mof (RNAi) induced apoptosis. The adult eye ablation phenotype produced by ectopic expression of Hid, Rpr and Grim, was restored by over expression of Mof. Accumulation of Mof at the Diap1 promoter 800 bp upstream of the transcription start site in wild type larvae is significantly higher (up to twofolds) compared to mof (1) mutants. This enrichment coincides with modification of histone H4K16Ac indicating an induction of direct transcriptional up regulation of Diap1 by Mof. Based on these results we propose that apoptosis triggered by mof (RNAi) proceeds through a caspase-dependent and JNK mediated pathway.

LR-90 prevents methylglyoxal-induced oxidative stress and apoptosis in human endothelial cells

PubMed Central

Figarola, James L.; Singhal, Jyotsana; Rahbar, Samuel; Awasthi, Sanjay

2014-01-01

Methylglyoxal (MGO) is a highly reactive dicarbonyl compound known to induce cellular injury and cytoxicity, including apoptosis in vascular cells. Vascular endothelial cell apoptosis has been implicated in the pathophysiology and progression of atherosclerosis. We investigated whether the advanced glycation end-product inhibitor LR-90 could prevent MGO-induced apoptosis in human umbilical vascular endothelial cells (HUVECs). HUVECs were pre-treated with LR-90 and then stimulated with MGO. Cell morphology, cytotoxicity and apoptosis were evaluated by light microscopy, MTT assay, and Annexin V-FITC and propidium iodide double staining, respectively. Levels of Bax, Bcl-2, cytochrome c, mitogen-activated protein kinases (MAPKs) and caspase activities were assessed by Western blotting. Reactive oxygen species (ROS) generation and mitochondrial membrane potential (MMP) were measured with fluorescent probes. LR-90 dose-dependently prevented MGO-associated HUVEC cytotoxicity and apoptotic biochemical changes such as loss of MMP, increased Bax/Bcl-2 protein ratio, mitochondrial cytochrome c release and activation of caspase-3 and 9. Additionally, LR-90 blocked intracellular ROS formation and MAPK (p44/p42, p38, JNK) activation, though the latter seem to be not directly involved in MGO-induced HUVEC apoptosis. LR-90 prevents MGO-induced HUVEC apoptosis by inhibiting ROS and associated mitochondrial-dependent apoptotic signaling cascades, suggesting that LR-90 possess cytoprotective ability which could be beneficial in prevention of diabetic related-atherosclerosis. PMID:24615331

Herbal medicine as inducers of apoptosis in cancer treatment.

PubMed

Safarzadeh, Elham; Sandoghchian Shotorbani, Siamak; Baradaran, Behzad

2014-10-01

Cancer is uncontrolled growth of abnormal cells in the body. Nowadays, cancer is considered as a human tragedy and one of the most prevalent diseases in the wide, and its mortality resulting from cancer is being increased. It seems necessary to identify new strategies to prevent and treat such a deadly disease. Control survival and death of cancerous cell are important strategies in the management and therapy of cancer. Anticancer agents should kill the cancerous cell with the minimal side effect on normal cells that is possible through the induction of apoptosis. Apoptosis is known as programmed cell death in both normal and damaged tissues. This process includes some morphologically changes in cells such as rapid condensation and budding of the cell, formation of membrane-enclosed apoptotic bodies with well-preserved organelles. Induction of apoptosis is one of the most important markers of cytotoxic antitumor agents. Some natural compounds including plants induce apoptotic pathways that are blocked in cancer cells through various mechanisms in cancer cells. Multiple surveys reported that people with cancer commonly use herbs or herbal products. Vinca Alkaloids, Texans, podo phyllotoxin, Camptothecins have been clinically used as Plant derived anticancer agents. The present review summarizes the literature published so far regarding herbal medicine used as inducers of apoptosis in cancer.

Antidepressant effects of combination of brexpiprazole and fluoxetine on depression-like behavior and dendritic changes in mice after inflammation.

PubMed

Ma, Min; Ren, Qian; Yang, Chun; Zhang, Ji-Chun; Yao, Wei; Dong, Chao; Ohgi, Yuta; Futamura, Takashi; Hashimoto, Kenji

2017-02-01

Addition of low doses of atypical antipsychotic drugs with selective serotonin reuptake inhibitors (SSRIs) could promote a rapid antidepressant effect in treatment-resistant patients with major depression. Brexpiprazole, a new atypical antipsychotic drug, has been used as adjunctive therapy for the treatment of major depression. The present study was undertaken to examine whether brexpiprazole could augment antidepressant effects of the SSRI fluoxetine in an inflammation model of depression. We examined the effects of fluoxetine (10 mg/kg), brexpiprazole (0.1 mg/kg), or the combination of the two drugs on depression-like behavior, alterations in the brain-derived neurotrophic factor (BDNF) - TrkB signaling, and dendritic spine density in selected brain regions after administration of lipopolysaccharide (LPS) (0.5 mg/kg). Combination of brexpiprazole and fluoxetine promoted a rapid antidepressant effect in inflammation model although brexpipazole or fluoxetine alone did not show antidepressant effect. Furthermore, the combination significantly improved LPS-induced alterations in the BDNF - TrkB signaling and dendritic spine density in the prefrontal cortex, CA3 and dentate gyrus, and nucleus accumbens. These results suggest that add-on of brexpiprazole to fluoxetine can produce a rapid antidepressant effect in the LPS inflammation model of depression, indicating that adjunctive therapy of brexpiprazole to SSRIs could produce a rapid antidepressant effect in depressed patients with inflammation.

Peer social interaction is facilitated in juvenile rhesus monkeys treated with fluoxetine.

PubMed

Golub, Mari S; Hogrefe, Casey E; Bulleri, Alicia M

2016-06-01

Fluoxetine improves social interactions in children with autism, social anxiety and social phobia. It is not known whether this effect is mediated directly or indirectly by correcting the underlying pathology. Genetics may also influence the drug effect. Polymorphisms of the MAOA (monoamine oxidase A) gene interact with fluoxetine to influence metabolic profiles in juvenile monkeys. Juvenile nonhuman primates provide an appropriate model for studying fluoxetine effects and drug*gene interactions in children. Male rhesus monkeys 1-3 years of age living in permanent social pairs were treated daily with a therapeutic dose of fluoxetine or vehicle (n = 16/group). Both members of each social pair were assigned to the same treatment group. They were observed for social interactions with their familiar cagemate over a 2-year dosing period. Subjects were genotyped for MAOA variable number of tandem repeats (VNTR) polymorphisms categorized for high or low transcription rates (hi-MAOA, low-MAOA). Fluoxetine-treated animals spent 30% more time in social interaction than vehicle controls. Fluoxetine significantly increased the duration of quiet interactions, the most common type of interaction, and also of immature sexual behavior typical of rhesus in this age group. Specific behaviors affected depended on MAOA genotype of the animal and its social partner. When given fluoxetine, hi-MOAO monkeys had more social invitation and initiation behaviors and low-MAOA subjects with low-MAOA partners had more grooming and an increased frequency of some facial and vocal expressive behaviors. Fluoxetine may facilitate social interaction in children independent of remediation of psychopathology. Common genetic variants may modify this effect. Copyright © 2016 Elsevier Ltd. All rights reserved.

Peer social interaction is facilitated in juvenile rhesus monkeys treated with fluoxetine

PubMed Central

Golub, Mari S.; Hogrefe, Casey E.; Bulleri, Alicia M.

2016-01-01

Background Fluoxetine improves social interactions in children with autism, social anxiety and social phobia. It is not known whether this effect is mediated directly or indirectly by correcting the underlying pathology. Genetics may also influence the drug effect. Polymorphisms of the MAOA (monoamine oxidase A) gene interact with fluoxetine to influence metabolic profiles in juvenile monkeys. Juvenile nonhuman primates provide an appropriate model for studying fluoxetine effects and drug*gene interactions in children. Methods Male rhesus monkeys 1–3 years of age living in permanent social pairs were treated daily with a therapeutic dose of fluoxetine or vehicle (n=16/group). Both members of each social pair were assigned to the same treatment group. They were observed for social interactions with their familiar cagemate over a 2-year dosing period. Subjects were genotyped for MAOA variable number of tandem repeats (VNTR) polymorphisms categorized for high or low transcription rates (hi-MAOA, low-MAOA). Results Fluoxetine-treated animals spent 30% more time in social interaction than vehicle controls. Fluoxetine significantly increased the duration of quiet interactions, the most common type of interaction, and also of immature sexual behavior typical of rhesus in this age group. Specific behaviors affected depended on MAOA genotype of the animal and its social partner. When given fluoxetine, hi-MOAO monkeys had more social invitations and initiation behaviors and low-MAOA subjects with low-MAOA partners had more grooming and an increased frequency of some facial and vocal expressive behaviors. Conclusions Fluoxetine may facilitate social interaction in children independent of remediation of psychopathology. Common genetic variants may modify this effect. PMID:26905291

Fluoxetine Does Not Enhance Visual Perceptual Learning and Triazolam Specifically Impairs Learning Transfer

PubMed Central

Lagas, Alice K.; Black, Joanna M.; Byblow, Winston D.; Fleming, Melanie K.; Goodman, Lucy K.; Kydd, Robert R.; Russell, Bruce R.; Stinear, Cathy M.; Thompson, Benjamin

2016-01-01

The selective serotonin reuptake inhibitor fluoxetine significantly enhances adult visual cortex plasticity within the rat. This effect is related to decreased gamma-aminobutyric acid (GABA) mediated inhibition and identifies fluoxetine as a potential agent for enhancing plasticity in the adult human brain. We tested the hypothesis that fluoxetine would enhance visual perceptual learning of a motion direction discrimination (MDD) task in humans. We also investigated (1) the effect of fluoxetine on visual and motor cortex excitability and (2) the impact of increased GABA mediated inhibition following a single dose of triazolam on post-training MDD task performance. Within a double blind, placebo controlled design, 20 healthy adult participants completed a 19-day course of fluoxetine (n = 10, 20 mg per day) or placebo (n = 10). Participants were trained on the MDD task over the final 5 days of fluoxetine administration. Accuracy for the trained MDD stimulus and an untrained MDD stimulus configuration was assessed before and after training, after triazolam and 1 week after triazolam. Motor and visual cortex excitability were measured using transcranial magnetic stimulation. Fluoxetine did not enhance the magnitude or rate of perceptual learning and full transfer of learning to the untrained stimulus was observed for both groups. After training was complete, trazolam had no effect on trained task performance but significantly impaired untrained task performance. No consistent effects of fluoxetine on cortical excitability were observed. The results do not support the hypothesis that fluoxetine can enhance learning in humans. However, the specific effect of triazolam on MDD task performance for the untrained stimulus suggests that learning and learning transfer rely on dissociable neural mechanisms. PMID:27807412

Fluoxetine-treated male wrasses exhibit low AVT expression.

PubMed

Semsar, Katharine; Perreault, Heidi A N; Godwin, John

2004-12-17

In many species, increasing serotonergic activity can reduce aggression and reverse dominance relationships. These effects may in part be mediated through interactions with the arginine vasotocin/vasopressin (AVT/AVP) system. We tested this hypothesis in a territorial coral reef fish, the bluehead wrasse (Thalassoma bifasciatum), by experimentally enhancing serotonergic neurotransmission, using the selective serotonin re-uptake inhibitor (SSRI) fluoxetine. Terminal phase (TP) males received 2 weeks of nightly intraperitoneal fluoxetine injections (6 microg/g body weight) and were then tested for their aggressive response to an intruder and killed to examine AVT phenotype in the preoptic area of the hypothalamus (POA), an area important to social behavior in fishes. Our previously published study demonstrated that fluoxetine-treated males are less aggressive [H.A.N. Perreault, K. Semsar, J. Godwin, Fluoxetine treatment decreases territorial aggression in a coral reef fish, Physiol. and Behav. 79 (2003) 719-724.]. Here, further study of these same fluoxetine-treated males shows approximately twofold lower AVT mRNA expression relative to saline-treated controls in all regions of the POA (all p< or =0.05) without any changes in AVT-ir soma size (all p>0.4). This study experimentally supports the hypothesis that behavioral effects of SSRIs may be mediated in part through interactions with the AVT/AVP system. These results parallel findings from rodents and humans and are consistent with an indirect neurosteroidogenic rather than a solely direct serotonergic mechanism for SSRI effects on the AVT/AVP system. Furthermore, they suggest that SSRI effects on neuroendocrine function may be best modeled in animals with sensitive stress responses such as those found in nondomesticated animals.

Valsartan protects HK-2 cells from contrast media-induced apoptosis by inhibiting endoplasmic reticulum stress.

PubMed

Peng, Ping-An; Wang, Le; Ma, Qian; Xin, Yi; Zhang, Ou; Han, Hong-Ya; Liu, Xiao-Li; Ji, Qing-Wei; Zhou, Yu-Jie; Zhao, Ying-Xin

2015-12-01

Contrast-induced acute kidney injury (CI-AKI) is associated with increasing in-hospital and long-term adverse clinical outcomes in high-risk patients undergoing percutaneous coronary intervention (PCI). Contrast media (CM)-induced renal tubular cell apoptosis is reported to participate in this process by activating endoplasmic reticulum (ER) stress. An angiotensin II type 1 receptor (AT1R) antagonist can alleviate ER stress-induced renal apoptosis in streptozotocin (STZ)-induced diabetic mice and can reduce CM-induced renal apoptosis by reducing oxidative stress and reversing the enhancement of bax mRNA and the reduction of bcl-2 mRNA, but the effect of the AT1R blocker on ER stress in the pathogenesis of CI-AKI is still unknown. In this study, we explored the effect of valsartan on meglumine diatrizoate-induced human renal tubular cell apoptosis by measuring changes in ER stress-related biomarkers. The results showed that meglumine diatrizoate caused significant cell apoptosis by up-regulating the expression of ER stress markers, including glucose-regulated protein 78 (GRP78), activating transcription factor 4 (ATF4), CCAAT/enhancer-binding protein-homologous protein (CHOP) and caspase 12, in a time- and dose-dependent manner, which could be alleviated by preincubation with valsartan. In conclusion, valsartan had a potential nephroprotective effect on meglumine diatrizoate-induced renal cell apoptosis by inhibiting ER stress. © 2015 International Federation for Cell Biology.

Knockdown of peroxiredoxin V increases glutamate‑induced apoptosis in HT22 hippocampal neuron cells.

PubMed

Shen, Gui-Nan; Liu, Lei; Feng, Li; Jin, Yu; Jin, Mei-Hua; Han, Ying-Hao; Jin, Cheng-Hao; Jin, Yong-Zhe; Lee, Dong-Soek; Kwon, Tae Ho; Cui, Yu-Dong; Sun, Hu-Nan

2018-06-01

High concentrations of glutamate may mediate neuronal cell apoptosis by increasing intracellular reactive oxygen species (ROS) levels. Peroxiredoxin V (Prx V), a member of the Prx family, serves crucial roles in protecting cells from oxidative stress. The present study investigated the regulatory effect of Prx V on glutamate‑induced effects on viability and apoptosis in HT22 cells. Western blotting was used for protein expression analysis and Annexin V/PI staining and flow cytometry for determination of apoptosis. The results demonstrated that glutamate may ROS‑dependently increase HT22 cell apoptosis and upregulate Prx V protein levels. Furthermore, knockdown of Prx V protein expression with a lentivirus significantly enhanced HT22 cell apoptosis mediated by glutamate, which was reversed by inhibition of ROS with N‑acetyl‑L‑cysteine. Inhibiting the extracellular signal‑regulated kinase (ERK) signaling pathway with PD98059, a specific inhibitor for ERK phosphorylation, markedly decreased glutamate‑induced HT22 cell apoptosis in Prx V knockdown cells, indicating the potential involvement of ERK signaling in glutamate‑induced HT22 cell apoptosis. In addition, an increase in nuclear apoptosis‑inducing factor was observed in Prx V knockdown HT22 cells following glutamate treatment, compared with mock cells, whereas no differences in B‑cell lymphoma‑2 and cleaved‑caspase‑3 protein expression levels were observed between mock and Prx V knockdown cells. The results of the present study indicated that Prx V may have potential as a therapeutic molecular target for glutamate‑induced neuronal cell death and provide novel insight into the role of Prx V in oxidative‑stress induced neuronal cell death.

Aminomethylphosphonic Acid and Methoxyacetic Acid Induce Apoptosis in Prostate Cancer Cells

PubMed Central

Parajuli, Keshab R.; Zhang, Qiuyang; Liu, Sen; You, Zongbing

2015-01-01

Aminomethylphosphonic acid (AMPA) and its parent compound herbicide glyphosate are analogs to glycine, which have been reported to inhibit proliferation and promote apoptosis of cancer cells, but not normal cells. Methoxyacetic acid (MAA) is the active metabolite of ester phthalates widely used in industry as gelling, viscosity and stabilizer; its exposure is associated with developmental and reproductive toxicities in both rodents and humans. MAA has been reported to suppress prostate cancer cell growth by inducing growth arrest and apoptosis. However, it is unknown whether AMPA and MAA can inhibit cancer cell growth. In this study, we found that AMPA and MAA inhibited cell growth in prostate cancer cell lines (LNCaP, C4-2B, PC-3 and DU-145) through induction of apoptosis and cell cycle arrest at the G1 phase. Importantly, the AMPA-induced apoptosis was potentiated with the addition of MAA, which was due to downregulation of the anti-apoptotic gene baculoviral inhibitor of apoptosis protein repeat containing 2 (BIRC2), leading to activation of caspases 7 and 3. These results demonstrate that the combination of AMPA and MAA can promote the apoptosis of prostate cancer cells, suggesting that they can be used as potential therapeutic drugs in the treatment of prostate cancer. PMID:26006246

Aminomethylphosphonic acid and methoxyacetic acid induce apoptosis in prostate cancer cells.

PubMed

Parajuli, Keshab R; Zhang, Qiuyang; Liu, Sen; You, Zongbing

2015-05-22

Aminomethylphosphonic acid (AMPA) and its parent compound herbicide glyphosate are analogs to glycine, which have been reported to inhibit proliferation and promote apoptosis of cancer cells, but not normal cells. Methoxyacetic acid (MAA) is the active metabolite of ester phthalates widely used in industry as gelling, viscosity and stabilizer; its exposure is associated with developmental and reproductive toxicities in both rodents and humans. MAA has been reported to suppress prostate cancer cell growth by inducing growth arrest and apoptosis. However, it is unknown whether AMPA and MAA can inhibit cancer cell growth. In this study, we found that AMPA and MAA inhibited cell growth in prostate cancer cell lines (LNCaP, C4-2B, PC-3 and DU-145) through induction of apoptosis and cell cycle arrest at the G1 phase. Importantly, the AMPA-induced apoptosis was potentiated with the addition of MAA, which was due to downregulation of the anti-apoptotic gene baculoviral inhibitor of apoptosis protein repeat containing 2 (BIRC2), leading to activation of caspases 7 and 3. These results demonstrate that the combination of AMPA and MAA can promote the apoptosis of prostate cancer cells, suggesting that they can be used as potential therapeutic drugs in the treatment of prostate cancer.

Vimentin Is Involved in Peptidylarginine Deiminase 2-Induced Apoptosis of Activated Jurkat Cells

PubMed Central

Hsu, Pei-Chen; Liao, Ya-Fan; Lin, Chin-Li; Lin, Wen-Hao; Liu, Guang-Yaw; Hung, Hui-Chih

2014-01-01

Peptidylarginine deiminase type 2 (PADI2) deiminates (or citrullinates) arginine residues in protein to citrulline residues in a Ca2+-dependent manner, and is found in lymphocytes and macrophages. Vimentin is an intermediate filament protein and a well-known substrate of PADI2. Citrullinated vimentin is found in ionomycin-induced macrophage apoptosis. Citrullinated vimentin is the target of anti-Sa antibodies, which are specific to rheumatoid arthritis, and play a critical role in the pathogenesis of the disease. To investigate the role of PADI2 in apoptosis, we generated a Jurkat cell line that overexpressed the PADI2 transgene from a tetracycline-inducible promoter, and used a combination of 12-O-tetradecanoylphorbol-13-acetate and ionomycin to activate Jurkat cells. We found that PADI2 overexpression reduced the cell viability of activated Jurkat cells in a dose- and time-dependent manner. The PADI2-overexpressed and -activated Jurkat cells presented typical manifestations of apoptosis, and exhibited greater levels of citrullinated proteins, including citrullinated vimentin. Vimentin overexpression rescued a portion of the cells from apoptosis. In conclusion, PADI2 overexpression induces apoptosis in activated Jurkat cells. Vimentin is involved in PADI2-induced apoptosis. Moreover, PADI2-overexpressed Jurkat cells secreted greater levels of vimentin after activation, and expressed more vimentin on their cell surfaces when undergoing apoptosis. Through artificially highlighting PADI2 and vimentin, we demonstrated that PADI2 and vimentin participate in the apoptotic mechanisms of activated T lymphocytes. The secretion and surface expression of vimentin are possible ways of autoantigen presentation to the immune system. PMID:24850148

Agarol, an ergosterol derivative from Agaricus blazei, induces caspase-independent apoptosis in human cancer cells.

PubMed

Shimizu, Takamitsu; Kawai, Junya; Ouchi, Kenji; Kikuchi, Haruhisa; Osima, Yoshiteru; Hidemi, Rikiishi

2016-04-01

Agaricus blazei (A. blazei) is a mushroom with many biological effects and active ingredients. We purified a tumoricidal substance from A. blazei, an ergosterol derivative, and named it 'Agarol'. Cytotoxic effects of Agarol were determined by the MTT assay using A549, MKN45, HSC-3, and HSC-4 human carcinoma cell lines treated with Agarol. Apoptosis was detected by flow cytometry analysis. Reactive oxygen species (ROS) levels and mitochondria membrane potential (∆ψm) were also determined by flow cytometry. Western blot analysis was used to quantify the expression of apoptosis-related proteins. Agarol predominantly induced apoptosis in two p53-wild cell lines (A549 and MKN45) compared to the other p53-mutant cell lines (HSC-3 and HSC-4). Further mechanistic studies revealed that induction of apoptosis is associated with increased generation of ROS, reduced ∆ψm, release of apoptosis-inducing factor (AIF) from the mitochondria to the cytosol, upregulation of Bax, and downregulation of Bcl-2. Caspase-3 activities did not increase, and z-VAD-fmk, a caspase inhibitor, did not inhibit the Agarol-induced apoptosis. These findings indicate that Agarol induces caspase-independent apoptosis in human carcinoma cells through a mitochondrial pathway. The in vivo anticancer activity of Agarol was confirmed in a xenograft murine model. This study suggests a molecular mechanism by which Agarol induces apoptosis in human carcinoma cells and indicates the potential use of Agarol as an anticancer agent.

Free Fatty Acids Shift Insulin-induced Hepatocyte Proliferation towards CD95-dependent Apoptosis*

PubMed Central

Sommerfeld, Annika; Reinehr, Roland; Häussinger, Dieter

2015-01-01

Insulin is known to induce hepatocyte swelling, which triggers via integrins and c-Src kinase an activation of the epidermal growth factor receptor (EGFR) and subsequent cell proliferation (1). Free fatty acids (FFAs) are known to induce lipoapoptosis in liver cells in a c-Jun-NH2-terminal kinase (JNK)-dependent, but death receptor-independent way (2). As non-alcoholic steatohepatitis (NASH) is associated with hyperinsulinemia and increased FFA-blood levels, the interplay between insulin and FFA was studied with regard to hepatocyte proliferation and apoptosis in isolated rat and mouse hepatocytes. Saturated long chain FFAs induced apoptosis and JNK activation in primary rat hepatocytes, but did not activate the CD95 (Fas, APO-1) system, whereas insulin triggered EGFR activation and hepatocyte proliferation. Coadministration of insulin and FFAs, however, abolished hepatocyte proliferation and triggered CD95-dependent apoptosis due to a JNK-dependent association of the activated EGFR with CD95, subsequent CD95 tyrosine phosphorylation and formation of the death-inducing signaling complex (DISC). JNK inhibition restored the proliferative insulin effect in presence of FFAs and prevented EGFR/CD95 association, CD95 tyrosine phosphorylation and DISC formation. Likewise, in presence of FFAs insulin increased apoptosis in hepatocytes from wild type but not from Alb-Cre-FASfl/fl mice, which lack functional CD95. It is concluded that FFAs can shift insulin-induced hepatocyte proliferation toward hepatocyte apoptosis by triggering a JNK signal, which allows activated EGFR to associate with CD95 and to trigger CD95-dependent apoptosis. Such phenomena may contribute to the pathogenesis of NASH. PMID:25548285

Lingonberry anthocyanins protect cardiac cells from oxidative-stress-induced apoptosis.

PubMed

Isaak, Cara K; Petkau, Jay C; Blewett, Heather; O, Karmin; Siow, Yaw L

2017-08-01

Lingonberry grown in northern Manitoba, Canada, contains exceptionally high levels of anthocyanins and other polyphenols. Previous studies from our lab have shown that lingonberry anthocyanins can protect H9c2 cells from ischemia-reperfusion injury and anthocyanin-rich diets have been shown to be associated with decreased cardiovascular disease and mortality. Oxidative stress can impair function and trigger apoptosis in cardiomyocytes. This study investigated the protective effects of physiologically relevant doses of lingonberry extracts and pure anthocyanins against hydrogen-peroxide-induced cell death. Apoptosis and necrosis were detected in H9c2 cells after hydrogen peroxide treatment via flow cytometry using FLICA 660 caspase 3/7 combined with YO-PRO-1 and then confirmed with Hoechst staining and fluorescence microscopy. Each of the 3 major anthocyanins found in lingonberry (cyanidin-3-galactoside, cyanidin-3-glucoside, and cyanidin-3-arabinoside) was protective against hydrogen-peroxide-induced apoptosis in H9c2 cells at 10 ng·mL -1 (20 nmol·L -1 ) and restored the number of viable cells to match the control group. A combination of the 3 anthocyanins was also protective and a lingonberry extract tested at 3 concentrations produced a dose-dependent protective effect. Lingonberry anthocyanins protected cardiac cells from oxidative-stress-induced apoptosis and may have cardioprotective effects as a dietary modification.

GSK-3beta inhibition enhances sorafenib-induced apoptosis in melanoma cell lines.

PubMed

Panka, David J; Cho, Daniel C; Atkins, Michael B; Mier, James W

2008-01-11

Glycogen synthase kinase-3beta (GSK-3beta) can participate in the induction of apoptosis or, alternatively, provide a survival signal that minimizes cellular injury. We previously demonstrated that the multikinase inhibitor sorafenib induces apoptosis in melanoma cell lines. In this report, we show that sorafenib activates GSK-3beta in multiple subcellular compartments and that this activation undermines the lethality of the drug. Pharmacologic inhibition and/or down-modulation of the kinase enhances sorafenib-induced apoptosis as determined by propidium iodide staining and by assessing the mitochondrial release of apoptosis-inducing factor and Smac/DIABLO. Conversely, the forced expression of a constitutively active form of the enzyme (GSK-3beta(S9A)) protects the cells from the apoptotic effects of the drug. This protective effect is associated with a marked increase in basal levels of Bcl-2, Bcl-x(L), and survivin and a diminution in the degree to which these anti-apoptotic proteins are down-modulated by sorafenib exposure. Sorafenib down-modulates the pro-apoptotic Bcl-2 family member Noxa in cells with high constitutive GSK-3beta activity. Pharmacologic inhibition of GSK-3beta prevents the disappearance of Noxa induced by sorafenib and enhances the down-modulation of Mcl-1. Down-modulation of Noxa largely eliminates the enhancing effect of GSK-3 inhibition on sorafenib-induced apoptosis. These data provide a strong rationale for the use of GSK-3beta inhibitors as adjuncts to sorafenib treatment and suggest that preservation of Noxa may contribute to their efficacy.

Gallic acid induces apoptosis in EGFR-mutant non-small cell lung cancers by accelerating EGFR turnover.

PubMed

Nam, Boas; Rho, Jin Kyung; Shin, Dong-Myung; Son, Jaekyoung

2016-10-01

Gallic acid is a common botanic phenolic compound, which is present in plants and foods worldwide. Gallic acid is implicated in various biological processes such as cell growth and apoptosis. Indeed, gallic acid has been shown to induce apoptosis in many cancer types. However, the molecular mechanisms of gallic acid-induced apoptosis in cancer, particularly lung cancer, are still unclear. Here, we report that gallic acid induces apoptosis in EGFR-mutant non-small cell lung cancer (NSCLC) cells, but not in EGFR-WT NSCLC cells. Treatment with gallic acid resulted in a significant reduction in proliferation and induction of apoptosis, only in EGFR-mutant NSCLC cells. Interestingly, treatment with gallic acid led to a robust decrease in EGFR levels, which is critical for NSCLC survival. Treatment with gallic acid had no significant effect on transcription, but induced EGFR turnover. Indeed, treatment with a proteasome inhibitor dramatically reversed gallic acid-induced EGFR downregulation. Moreover, treatment with gallic acid induced EGFR turnover leading to apoptosis in EGFR-TKI (tyrosine kinase inhibitor)-resistant cell lines, which are dependent on EGFR signaling for survival. Thus, these studies suggest that gallic acid can induce apoptosis in EGFR-dependent lung cancers that are dependent on EGFR for growth and survival via acceleration of EGFR turnover. Copyright © 2016 Elsevier Ltd. All rights reserved.

Character and temporal evolution of apoptosis in acetaminophen-induced acute liver failure*.

PubMed

Possamai, Lucia A; McPhail, Mark J W; Quaglia, Alberto; Zingarelli, Valentina; Abeles, R Daniel; Tidswell, Robert; Puthucheary, Zudin; Rawal, Jakirty; Karvellas, Constantine J; Leslie, Elaine M; Hughes, Robin D; Ma, Yun; Jassem, Wayel; Shawcross, Debbie L; Bernal, William; Dharwan, Anil; Heaton, Nigel D; Thursz, Mark; Wendon, Julia A; Mitry, Ragai R; Antoniades, Charalambos G

2013-11-01

To evaluate the role of hepatocellular and extrahepatic apoptosis during the evolution of acetaminophen-induced acute liver failure. A prospective observational study in two tertiary liver transplant units. Eighty-eight patients with acetaminophen-induced acute liver failure were recruited. Control groups included patients with nonacetaminophen-induced acute liver failure (n = 13), nonhepatic multiple organ failure (n = 28), chronic liver disease (n = 19), and healthy controls (n = 11). Total and caspase-cleaved cytokeratin-18 (M65 and M30) measured at admission and sequentially on days 3, 7, and 10 following admission. Levels were also determined from hepatic vein, portal vein, and systemic arterial blood in seven patients undergoing transplantation. Protein arrays of liver homogenates from patients with acetaminophen-induced acute liver failure were assessed for apoptosis-associated proteins, and histological assessment of liver tissue was performed. Admission M30 levels were significantly elevated in acetaminophen-induced acute liver failure and non-acetaminophen induced acute liver failure patients compared with multiple organ failure, chronic liver disease, and healthy controls. Admission M30 levels correlated with outcome with area under receiver operating characteristic of 0.755 (0.639-0.885, p < 0.001). Peak levels in patients with acute liver failure were seen at admission then fell significantly but did not normalize over 10 days. A negative gradient of M30 from the portal to hepatic vein was demonstrated in patients with acetaminophen-induced acute liver failure (p = 0.042) at the time of liver transplant. Analysis of protein array data demonstrated lower apoptosis-associated protein and higher catalase concentrations in acetaminophen-induced acute liver failure compared with controls (p < 0.05). Explant histological analysis revealed evidence of cellular proliferation with an absence of histological evidence of apoptosis. Hepatocellular apoptosis occurs

[Harringtonine induces apoptosis in NB4 cells through down-regulation of Mcl-1].

PubMed

Wu, Chunxiao; Shen, Hongqiang; Xia, Dajing

2013-07-01

To investigate the growth inhibition effect, cytotoxicity and apoptotic induction of harringtonine (HT) in human acute promyelocytic leukemia (APL) NB4 cells,and the related mechanism. NB4 cells were treated with HT. Total cell numbers were counted by hemocytometer, and cell viabilities were determined by trypan blue exclusion. Apoptotic cells were determined by fluorescence microscopy and FACS after staining with AO and EB or PI, respectively. The cleavage of PARP and the activation of Bax and the expression of anti-apoptotic proteins were determined by Western Blot. siRNA was used to silence the expression of target genes. Primary cells were isolated following Ficoll-Hypaque density gradient centrifugation method. HT inhibited cell growth and induced apoptosis of NB4 cells in a dose- and time-dependent manner. Apoptosis induced by HT was correlated with the down-regulation of Mcl-1 and the cleavage of PARP, while HT did not affect the protein level of Bax and Bak or change the protein level of Bcl-2. The silence of Bcl-XL sensitized HT-induced apoptosis in NB4 cells.Apoptosis induced by HT in primarily cultured APL cells was also correlated with the down-regulation of Mcl-1. HT inhibits cell growth and induces apoptosis in NB4 cells and primarily cultured APL cells, which may be associated with down-regulation of Mcl-1.

Chlorella vulgaris triggers apoptosis in hepatocarcinogenesis-induced rats*

PubMed Central

Mohd Azamai, Emey Suhana; Sulaiman, Suhaniza; Mohd Habib, Shafina Hanim; Looi, Mee Lee; Das, Srijit; Abdul Hamid, Nor Aini; Wan Ngah, Wan Zurinah; Mohd Yusof, Yasmin Anum

2009-01-01

Chlorella vulgaris (CV) has been reported to have antioxidant and anticancer properties. We evaluated the effect of CV on apoptotic regulator protein expression in liver cancer-induced rats. Male Wistar rats (200~250 g) were divided into eight groups: control group (normal diet), CDE group (choline deficient diet supplemented with ethionine in drinking water to induce hepatocarcinogenesis), CV groups with three different doses of CV (50, 150, and 300 mg/kg body weight), and CDE groups treated with different doses of CV (50, 150, and 300 mg/kg body weight). Rats were sacrificed at various weeks and liver tissues were embedded in paraffin blocks for immunohistochemistry studies. CV, at increasing doses, decreased the expression of anti-apoptotic protein, Bcl-2, but increased the expression of pro-apoptotic protein, caspase 8, in CDE rats, which was correlated with decreased hepatoctyes proliferation and increased apoptosis as determined by bromodeoxy-uridine (BrdU) labeling and terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling (TUNEL) assay, respectively. Our study shows that CV has definite chemopreventive effect by inducing apoptosis via decreasing the expression of Bcl-2 and increasing the expression of caspase 8 in hepatocarcinogenesis-induced rats. PMID:19198018

Amoebal Endosymbiont Protochlamydia Induces Apoptosis to Human Immortal HEp-2 Cells

PubMed Central

Ito, Atsushi; Matsuo, Junji; Nakamura, Shinji; Yoshida, Asahi; Okude, Miho; Hayashi, Yasuhiro; Sakai, Haruna; Yoshida, Mitsutaka; Takahashi, Kaori; Yamaguchi, Hiroyuki

2012-01-01

Protochlamydia, an environmental chlamydia and obligate amoebal endosymbiotic bacterium, evolved to survive within protist hosts, such as Acanthamobae, 700 million years ago. However, these bacteria do not live in vertebrates, including humans. This raises the possibility that interactions between Protochlamydia and human cells could induce a novel cytopathic effect, leading to new insights into host-parasite relationships. Therefore, we studied the effect of Protochlamydia on the survival of human immortal cell line, HEp-2 cells and primary peripheral blood mononuclear cells (PBMC). Using mainly 4′,6-diamidino-2-phenylindole staining, fluorescent in situ hybridization, transmission electron microscopy, and also TUNEL and Transwell assays, we demonstrated that the Protochlamydia induced apoptosis in HEp-2 cells. The attachment of viable bacterial cells, but not an increase of bacterial infectious progenies within the cells, was required for the apoptosis. Other chlamydiae [Parachlamydia acanthamoebae and Chlamydia trachomatis (serovars D and L2)] did not induce the same phenomena, indicating that the observed apoptosis may be specific to the Protochlamydia. Furthermore, the bacteria had no effect on the survival of primary PBMCs collected from five volunteers, regardless of activation. We concluded that Protochlamydia induces apoptosis in human-immortal HEp-2 cells and that this endosymbiont could potentially be used as a biological tool for the elucidation of novel host-parasite relationships. PMID:22276171

Amoebal endosymbiont Protochlamydia induces apoptosis to human immortal HEp-2 cells.

PubMed

Ito, Atsushi; Matsuo, Junji; Nakamura, Shinji; Yoshida, Asahi; Okude, Miho; Hayashi, Yasuhiro; Sakai, Haruna; Yoshida, Mitsutaka; Takahashi, Kaori; Yamaguchi, Hiroyuki

2012-01-01

Protochlamydia, an environmental chlamydia and obligate amoebal endosymbiotic bacterium, evolved to survive within protist hosts, such as Acanthamobae, 700 million years ago. However, these bacteria do not live in vertebrates, including humans. This raises the possibility that interactions between Protochlamydia and human cells could induce a novel cytopathic effect, leading to new insights into host-parasite relationships. Therefore, we studied the effect of Protochlamydia on the survival of human immortal cell line, HEp-2 cells and primary peripheral blood mononuclear cells (PBMC). Using mainly 4',6-diamidino-2-phenylindole staining, fluorescent in situ hybridization, transmission electron microscopy, and also TUNEL and Transwell assays, we demonstrated that the Protochlamydia induced apoptosis in HEp-2 cells. The attachment of viable bacterial cells, but not an increase of bacterial infectious progenies within the cells, was required for the apoptosis. Other chlamydiae [Parachlamydia acanthamoebae and Chlamydia trachomatis (serovars D and L2)] did not induce the same phenomena, indicating that the observed apoptosis may be specific to the Protochlamydia. Furthermore, the bacteria had no effect on the survival of primary PBMCs collected from five volunteers, regardless of activation. We concluded that Protochlamydia induces apoptosis in human-immortal HEp-2 cells and that this endosymbiont could potentially be used as a biological tool for the elucidation of novel host-parasite relationships.

Farnesol-induced apoptosis in Candida albicans.

PubMed

Shirtliff, Mark E; Krom, Bastiaan P; Meijering, Roelien A M; Peters, Brian M; Zhu, Jingsong; Scheper, Mark A; Harris, Megan L; Jabra-Rizk, Mary Ann

2009-06-01

Farnesol, a precursor in the isoprenoid/sterol pathway, was recently identified as a quorum-sensing molecule produced by the fungal pathogen Candida albicans. Farnesol is involved in the inhibition of germination and biofilm formation by C. albicans and can be cytotoxic at certain concentrations. In addition, we have shown that farnesol can trigger apoptosis in mammalian cells via the classical apoptotic pathways. In order to elucidate the mechanism behind farnesol cytotoxicity in C. albicans, the response to farnesol was investigated, using proteomic analysis. Global protein expression profiles demonstrated significant changes in protein expression resulting from farnesol exposure. Among the downregulated proteins were those involved in metabolism, glycolysis, protein synthesis, and mitochondrial electron transport and the respiratory chain, whereas proteins involved in folding, protection against environmental and oxidative stress, actin cytoskeleton reorganization, and apoptosis were upregulated. Cellular changes that accompany apoptosis (regulated cell death) were further analyzed using fluorescent microscopy and gene expression analysis. The results indicated reactive oxygen species accumulation, mitochondrial degradation, and positive terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) in the farnesol-exposed cells concurrent with increased expression of antioxidant-encoding and drug response genes. More importantly, the results demonstrated farnesol-induced upregulation of the caspase gene MCA1 and the intracellular presence of activated caspases. In conclusion, this study demonstrated that farnesol promotes apoptosis in C. albicans through caspase activation, implying an important physiological role for farnesol in the fungal cell life cycle with important implications for adaptation and survival.

High-density lipoproteins protect endothelial cells from tumor necrosis factor-alpha-induced apoptosis.

PubMed

Sugano, M; Tsuchida, K; Makino, N

2000-06-16

High-density lipoproteins (HDL) levels have been shown to be inversely correlated with coronary heart disease, but the mechanisms of the direct protective effect of HDL on endothelial cells are not fully understood. The apoptosis of endothelial cells induced by cytokines and/or oxidized low-density lipoproteins, etc. may provide a mechanistic clue to the "response-to-injury" hypothesis of atherogenesis. Here we report that HDL prevent the apoptosis of human umbilical venous endothelial cells (HUVECs) induced by tumor necrosis factor-alpha (TNF-alpha) via an inhibition of CPP32-like protease activity. The incubation of HUVECs with TNF-alpha significantly increased the CPP32-like protease activity, and induced apoptosis. Preincubation of HUVECs with HDL before incubation with TNF-alpha significantly suppressed the increase in the CPP32-like protease activity, preventing apoptosis in a concentration-dependent manner. These results suggest that HDL prevent the suicide pathway leading to apoptosis of endothelial cells by decreasing the CPP32-like protease activity and that HDL thus play a protective role against the "response-to-injury" hypothesis of atherogenesis. Copyright 2000 Academic Press.

Novel TRAIL sensitizer Taraxacum officinale F.H. Wigg enhances TRAIL-induced apoptosis in Huh7 cells.

PubMed

Yoon, Ji-Yong; Cho, Hyun-Soo; Lee, Jeong-Ju; Lee, Hyo-Jung; Jun, Soo Young; Lee, Jae-Hye; Song, Hyuk-Hwan; Choi, SangHo; Saloura, Vassiliki; Park, Choon Gil; Kim, Cheol-Hee; Kim, Nam-Soon

2016-04-01

TRAIL (TNF-related apoptosis inducing ligand) is a promising anti-cancer drug target that selectively induces apoptosis in cancer cells. However, many cancer cells are resistant to TRAIL-induced apoptosis. Therefore, reversing TRAIL resistance is an important step for the development of effective TRAIL-based anti-cancer therapies. We previously reported that knockdown of the TOR signaling pathway regulator-like (TIPRL) protein caused TRAIL-induced apoptosis by activation of the MKK7-c-Jun N-terminal Kinase (JNK) pathway through disruption of the MKK7-TIPRL interaction. Here, we identified Taraxacum officinale F.H. Wigg (TO) as a novel TRAIL sensitizer from a set of 500 natural products using an ELISA system and validated its activity by GST pull-down analysis. Furthermore, combination treatment of Huh7 cells with TRAIL and TO resulted in TRAIL-induced apoptosis mediated through inhibition of the MKK7-TIPRL interaction and subsequent activation of MKK7-JNK phosphorylation. Interestingly, HPLC analysis identified chicoric acid as a major component of the TO extract, and combination treatment with chicoric acid and TRAIL induced TRAIL-induced cell apoptosis via JNK activation due to inhibition of the MKK7-TIPRL interaction. Our results suggest that TO plays an important role in TRAIL-induced apoptosis, and further functional studies are warranted to confirm the importance of TO as a novel TRAIL sensitizer for cancer therapy. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.