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Reactive astrocytes are important pathophysiologically and synthesize neurosteroids. We observed that LPS increased immunoreactive TLR4 and key steroidogenic enzymes in cortical astrocytes of rats and investigated whether corticosteroids are produced and mediate astrocytic TLR4‐dependent innate immune responses. We found that LPS increased steroidogenic acute regulatory protein (StAR) and StAR‐dependent aldosterone production in purified astrocytes. Both increases were blocked by the TLR4 antagonist TAK242. LPS also increased 11β‐hydroxysteroid dehydrogenase type 1 (11β‐HSD1) and corticosterone production, and both were prevented by TAK242 and by siRNAs against 11β‐HSD1, StAR, or aldosterone synthase (CYP11B2). Knockdown of 11β‐HSD1, StAR, or CYP11B2 or blocking either mineralocorticoid receptors (MR) or glucocorticoid receptors (GR) prevented dephosphorylation of p‐Ser9GSK‐3β, activation of NF‐κB, and the GSK‐3β‐dependent increases of C3, IL‐1β, and TNF‐α caused by LPS. Exogenous aldosterone mimicked the MR‐ and GSK‐3β‐dependent pro‐inflammatory effects of LPS in astrocytes, but corticosterone did not. Supernatants from astrocytes treated with LPS reduced MAP2 and viability of cultured neurons except when astrocytic StAR or MR was inhibited. In adrenalectomized rats, intracerebroventricular injection of LPS increased astrocytic TLR4, StAR, CYP11B2, and 11β‐HSD1, NF‐κB, C3 and IL‐1β, decreased astrocytic p‐Ser9GSK‐3β in the cortex and was neurotoxic, except when spironolactone was co‐injected, consistent with the in vitro results. LPS also activated NF‐κB in some NeuN+ and CD11b+ cells in the cortex, and these effects were prevented by spironolactone. We conclude that intracrine aldosterone may be involved in the TLR4‐dependent innate immune responses of astrocytes and can trigger paracrine effects by activating astrocytic MR/GSK‐3β/NF‐κB signaling. [ABSTRACT FROM AUTHOR]

Objective(s): The process of vascular formation, also known as angiogenesis, primarily relies on endothelial cell proliferation, migration, and invasion. In recent years, it has been discovered that synthetic cannabinoids (SCs) may potentially impact angiogenic processes within the body. We evaluated the impact of the synthetic cannabinoid (R)-5-Fluoro-ADB on the proliferation rate and angiogenesis in Human Cerebral Microvascular Endothelial Cells (hBMECs). Materials and Methods: hBMECs were treated with (R)-5-Fluoro-ADB and investigated for cell viability, migration rate, and tube-like structure formation. Furthermore, angiogenic-related proteins including Angopoitein-1 and -2, and Vascular Endothelial Growth Factors (VEGF) were examined on mRNA and protein levels. Results: The results showed a notable rise in the rate of proliferation (P-value<0.0001) of HBMECs induced by (R)-5-Fluoro-ADB. The angiogenic capacity of HBMECs was also enhanced between 0.001 µM to 1 µM (R)-5-Fluoro-ADB. Moreover, an increase in the levels of ANG-1, ANG-2, and VEGF mRNA and protein, as well as elevated phosphorylation rate of GSK-3ß, were observed across various concentrations of (R)-5-Fluoro-ADB. Conclusion: Our results suggest an innovative approach in pharmacology for addressing a range of conditions linked to angiogenesis. This approach involves precise targeting of both cannabinoid receptors type-1 and -2. To achieve this, specific agonists or antagonists of these receptors could be employed based on the particular characteristics of the diseases in question. [ABSTRACT FROM AUTHOR]

Aims Sodium-glucose cotransporter 2 inhibitors have beneficial effects on heart failure and cardiovascular mortality in diabetic and non-diabetic patients, with unclear mechanisms. Autophagy is a cardioprotective mechanism under acute stress conditions, but excessive autophagy accelerates myocardial cell death leading to autosis. We evaluated the protective role of empagliflozin (EMPA) against cardiac injury in murine diabetic cardiomyopathy. Methods and results Male mice, rendered diabetics by one single intraperitoneal injection of streptozotocin and treated with EMPA (30 mg/kg/day), had fewer apoptotic cells (4.9 ± 2.1 vs. 1 ± 0.5 TUNEL-positive cells %, P < 0.05), less senescence (10.1 ± 2 vs. 7.9 ± 1.2 β-gal positivity/tissue area, P < 0.05), fibrosis (0.2 ± 0.05 vs. 0.15 ± 0.06, P < 0.05 fibrotic area/tissue area), autophagy (7.9 ± 0.05 vs. 2.3 ± 0.6 fluorescence intensity/total area, P < 0.01), and connexin (Cx)-43 lateralization compared with diabetic mice. Proteomic analysis showed a down-regulation of the 5′ adenosine monophosphate-activated protein kinase (AMPK) pathway and upstream activation of sirtuins in the heart of diabetic mice treated with EMPA compared with diabetic mice. Because sirtuin activation leads to the modulation of cardiomyogenic transcription factors, we analysed the DNA binding activity to serum response elements (SRE) of serum response factor (SRF) by electromobility shift assay. Compared with diabetic mice [0.5 ± 0.01 densitometric units (DU)], non-diabetic mice treated with EMPA (2.2 ± 0.01 DU, P < 0.01) and diabetic mice treated with EMPA (2.0 ± 0.1 DU, P < 0.01) significantly increased SRF binding activity to SRE, paralleled by increased cardiac actin expression (4.1 ± 0.1 vs. 2.2 ± 0.01 target protein/β-actin ratio, P < 0.01). EMPA significantly reversed cardiac dysfunction on echocardiography in diabetic mice and inhibited excessive autophagy in high-glucose-treated cardiomyocytes by inhibiting the autophagy inducer glycogen synthase kinase 3 beta (GSK3β), leading to reactivation of cardiomyogenic transcription factors. Conclusion Taken together, our results describe a novel paradigm in which EMPA inhibits hyperactivation of autophagy through the AMPK/GSK3β signalling pathway in the context of diabetes. [ABSTRACT FROM AUTHOR]

Background and Objective: Chronic use of opioids leads to analgesic tolerance. Protein kinase C (PKC), adenylyl cyclase (AC), nitric oxide (NO) and glycogen synthase kinase 3 beta (GSK-3β) are involved in morphine tolerance. Lithium activates the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (AKT) pathway that inhibits GSK-3β and reduces morphineinduced tolerance. This study was performed to evaluate the effects of lithium on morphine dependence symptoms and tolerance of its analgesic effects in Swiss mice by GSK-3β signaling. Methods: This experimental study was performed on 56 Swiss male albino mice that were randomly allocated into 8 groups (each containing 7 mice). The intraperitoneal injection of morphine at different concentrations (50, 50 and 75 mg/kg) and different hours (08:00, 11:00 and 16:00, respectively) was performed for 4 days, and a single dose 50 mg/kg was administered on the 5th day. The effects of three doses of lithium (1, 5 and 10 mg/kg) given orally, 45 min before morphine injections on morphine-induced analgesic tolerance were evaluated. To evaluate analgesia latency on day 1, 3 and 5, tail flick and hot plate tests were done. The brain of each animal was removed to measure nitrite levels, and histological evaluation and immunohistochemistry for p-glycogen synthase (p-GSSer640) were performed on the last day of the study. Results: Co-administration of lithium significantly increased the latency of analgesia in comparison with the morphine group on the 3rd and 5th day (P<0.05). Lithium reduced the morphine-induced increase of nitrite levels and also reduced brain damage. In addition, immunohistochemistry assay of p-GSSer640 indicated a significant reduction of the morphine-induced phosphorylation of GS at S640 by GSK in the lithium-treated mice. Conclusion: Lithium administration can reduce morphine tolerance in adult male Swiss mice. [ABSTRACT FROM AUTHOR]

To investigate the mechanism of ketamine promoting Alzheimer’s-like neurodegeneration in mice. 24 male 8 w old Kunming mice of specific pathogen-free grade were randomly divided into a blank control group (control group) and a ketamine intervention group (experimental group) according to the random number table, 12 mice in each group. The mice in the experimental group were given ketamine injection at the dose of 30 mg/kg. Mice in the control group were given an equal volume of normal saline injection. The intervention was conducted once a day for consecutive 6 mo. The behavioral changes of the mice in the two groups were compared. Western blot was used to detect the expression levels of tau (phospho Thr231), tau (phospho S396), tau (phospho Ser404), glycogen synthase kinase 3 beta, glycogen synthase kinase 3 beta (phospho ser9) and protein phosphatase 2A proteins in the brain tissue of hippocampus and the ratio of phosphorylated tau protein to tau protein was calculated. The expressions of beta-amyloid protein and tau protein in the hippocampus were observed by immunohistochemistry. The results of the Morris water maze showed that the escape latency of mice in both groups was gradually decreased and the escape latency of mice in the control group was lower than that in the experimental group. Besides, the times of crossing target platform and the proportion of activity time in target quadrant of mice in the experimental group were lower than those in the control group. At the same time, compared with the control group, the expression levels of tau (phospho Thr231) and tau (phospho Ser404) were decreased in the experimental group, and the expressions of tau (phospho S396), glycogen synthase kinase 3 beta, glycogen synthase kinase 3 beta (phospho ser9) and protein phosphatase 2A proteins were increased. Compared with the control group, the expression of beta-amyloid protein in the experimental group was significantly reduced and the opalescence density of beta-amyloid protein was significantly lower than that in the control group (p<0.05). Long-term use of ketamine can lead to up-regulated expression of beta-amyloid protein and tau protein in mice hippocampus, which may induce hyperphosphorylation of tau protein at Thr231, S396 and S404 by activating glycogen synthase kinase 3 beta and inhibiting protein phosphatase 2A, causing cognitive function decline in mice. [ABSTRACT FROM AUTHOR]

Mitochondria damage and apoptosis were found associated with sevoflurane induced neurotoxicity in developing brains of rodent and neuro cell lines. The detailed upstream mechanism remains unclear. This study explored whether sevoflurane induces neurotoxicity by activating a GSK3β (glycogen synthase kinase 3β)/Drp1 (dynamin-related protein-1)-dependent mitochondrial fission and apoptosis. Our results showed that sevoflurane exposure promoted mitochondria fission in hippocampus of neonatal mice, resulted in a prolonged escape latency from P32 (32-day-postnatal) to P35, and decreased platform crossing times on P36 as compared to the control treatment. Additionally, sevoflurane upregulated GSK3β stability and activation, promoted phosphorylation of Drp1 at Ser616 along with its translocation to mitochondria and resulted in increasing cytochrome c and cleaved casepase-3 in hippocampus of neonatal mice and in human SK-N-SH cells. Simultaneously, sevoflurane promoted the interaction between Drp1 and GSK3β. Furthermore, GSK3β activated phosphorylation of Drp1 at Ser616, induced mitochondrial fission, loss of mitochondrial membrane potential (MMP) and apoptosis in SK-N-SH cells, which was attenuated by TDZD-8, an inhibitor of GSK3β. In conclusion, sevoflurane induced neurotoxicity links to a GSK3β/Drp1 dependent mitochondrial fission and apoptosis. [Display omitted] • The potential risk of sevoflurane induced neurotoxicity in developing brain is a crucial issue in pediatric anesthesia. • This study demonstrated a novel upstream mechanism on sevoflurane-induced mitochondrial abnormalities and neurotoxicity. • Sevoflurane induced neurotoxicity in neonatal mice links to a GSK3β/Drp1-dependent mitochondrial fission and apoptosis. • Our results may contribute to the safety considerations on sevoflurane anesthesia in developing brain. [ABSTRACT FROM AUTHOR]

Objective To explore the molecular mechanism of naringenin in preventing and treating insulin resistance in rats with polycystic ovary syndrome (PCOS) based on the aspect of phosphatidylinositol 3 kinase (PI3K)/protein kinase B (AKT) pathway. Methods SD rats were injected with dehydroepiandrosterone subcutaneously on the back daily to establish a PCOS model. The model rats were randomly divided into the model group, the naringenin group, the PI3K inhibitor group, and the naringenin+PI3K inhibitor group, with 15 rats in each group. At the same time, 15 SD rats were subcutaneously injected with oil 2 mL/kg on the neck and back, and they were used as the normal control group. The levels of blood glucose, insulin, blood lipids, and reproductive hormones were detected in each group. The morphology of ovary was observed with HE staining. The positive expression of p-PI3K was detected with immunohistochemical method. The protein expression of PI3K/AKT pathway phosphorylated protein, and pathway related protein-insulin receptor substrate-1 (IRS-1), glycogen synthase-3β (GSK-3β), glucose transporter factor-4 (GLUT4), phosphatase and tensin homologue deleted on chromosome 10 (PTEN) were detected with Western blot assay. Results Compared with the normal control group, the ovarian tissue of the model group showed symptoms of pathological damage such as follicular cystic dilatation, decreased corpus luteum number and granulosa cell layer, and increased atretic follicles, increased levels of blood lipid and blood sugar, increased insulin resistance, and disordered secretion of reproductive hormones, decreased PI3K/AKT pathway phosphorylated proteins and pathway-related proteins IRS-1, GSK-3β phosphorylated protein and GLUT4 protein expression, and increased expression of PTEN protein (P＜0.05). Naringenin could reduce pathological damage such as cystic dilatation of follicles, promote PI3K/AKT pathway phosphorylated proteins and pathway-related proteins IRS-1, GSK-3β phosphorylated protein and GLUT4 protein expression, improve the disorder of reproductive hormone secretion, reduce insulin resistance, blood glucose and blood lipid levels and PTEN protein expression (P＜0.05). PI3K inhibitors could attenuate the above effects of naringenin (P＜0.05). Conclusion Naringenin can promote the activation of PI3K/AKT pathway, reduce blood glucose and blood lipid levels and insulin resistance, and improve reproductive hormone disorders and ovarian polycystic changes in PCOS rats. [ABSTRACT FROM AUTHOR]

The protective mechanism of ginsenoside Rg1 for Alzheimer's disease induced by Amyloid β-Protein has rarely been reported. To evaluate the cerebroprotective effects of ginsenoside Rg1 on Alzheimer's disease rats. Male Sprague Dawley rats were randomly divided into 5 groups (n=10). Alzheimer's disease model was established by injecting Amyloid β-Protein into the hippocampal CA1 area. Rg1 group, specific phosphoinositide 3-kinase inhibitor LY294002 group and Rg1 plus LY294002 group were intraperitoneally injected with corresponding drugs, once daily for 28 consecutive d. The spatial learning and memory abilities were studied by water maze and platform tests respectively. The pathological changes of hippocampal CA1 area were observed by hematoxylin and eosin staining. Neuronal apoptosis was detected by Terminal deoxynucleotidyl transferase dUTP Nick-End Labeling assay. Protein kinase B and Glycogen synthase kinase 3 beta protein expressions were measured by Western blotting. Compared with model group, the learning and memory abilities of Rg1 group were significantly improved (p<0.05), and the abnormal morphology of neurons in Rg1 group and their apoptosis were significantly relieved (p<0.05). Compared with model group, the superoxide dismutase and glutathione peroxidase levels of Rg1 group increased significantly, whereas that of Malondialdehyde decreased significantly (p<0.05). Compared with model group, the Protein kinase B and Glycogen synthase kinase 3 beta phosphorylation levels of Rg1 group significantly increased (p<0.05). LY294002 and Rg1+LY294002 groups had similar results (p>0.05). Ginsenoside Rg1 may mitigate Amyloid β-Protein induced Alzheimer's disease by activating the phosphoinositide 3-kinase/Protein kinase B/Glycogen synthase kinase 3 beta signaling pathway, inhibit neuronal apoptosis in the hippocampus and attenuate oxidative stress, exerting cerebroprotective effects. [ABSTRACT FROM AUTHOR]

: Objective To investigate the effect and mechanism of gastrodin on head twitch behavior in rats with Tourette syndrome (TS). Methods 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) induction method was used to replicate TS rat model. Forty Wistar rats were randomly divided into four groups (n=10): the normal group (gastric administration of normal saline), the TS model group (from the first day of modeling, intragastric administration with normal saline at 2 h after DOI injection), the TS+ gastrodin group (from the first day of modeling, intragastric administration with 30 mg/kg gastrodin at 2 h after DOI injection), and the TS+gastrodin+CHIR-99021 group [glycogen synthase kinase-3β (GSK3β) inhibitor] (from the first day of modeling, 2 h after DOI injection, intraperitoneal injection with 2 mg/kg CHIR-99021 firstly, and then intragastric administration with 30 mg/kg gastrodin), continuous administration for 21 d. After the last administration, the rat’s head twitching behavior within 30 min was counted. The levels of striatal 5-hydroxyindole (5-HT), 5-hydroxyindole acetic acid (5-HIAA), and dopamine (DA) were detected by kits. The number of DA neurons in the substantia nigra was detected by immunohistochemical method. The expression of 5-HT transporter (SERT), 5- hydroxyindole 2A receptor (5-HT2AR), 5-hydroxyindole 2C receptor (5-HT2CR) and GSK-3β phosphorylation in the striatum were detected by Western blot assay. Results Compared with the normal group, the number of head twitches, DA level, number of DA neurons, SERT level and p-S9-GSK-3β, p-S9-GSK-3β/t-GSK-3β level increased in the TS model group, and the 5-HT level decreased (P＜0.05). Compared with the TS model group, the number of head twitches, DA level, number of DA neurons, SERT level and p-S9-GSK-3β, p-S9-GSK-3β/t-GSK-3β level decreased in the TS+gastrodin group, and the 5-HT level increased (P＜0.05). Compared with the TS+gastrodin group, the number of head twitches, DA level, number of DA neurons, SERT level and p-S9-GSK-3β, p-S9-GSK-3β/t-GSK-3β level increased, and the 5-HT level decreased in the TS+gastrodin+CHIR-99021 group (P＜0.05). Conclusion Gastrodin can improve the head twitch behavior of TS rats, and its mechanism may be by inhibiting the phosphorylation of GSK-3β, regulating the expression of SERT, affecting the level of 5-HT, and then inhibiting the release of DA in striatum. [ABSTRACT FROM AUTHOR]

Alterations in prolyl oligopeptidase (PREP) activity have been connected, for example, with bipolar and major depressive disorder, and several studies have reported that lack or inhibition of PREP blocks the effects of lithium on inositol 1,4,5‐triphosphate (IP3) levels. However, the impact of PREP modulation on other intracellular targets of lithium, such as glycogen synthase kinase 3 beta (GSK3b) or protein kinase B (Akt), has not been studied. We recently found that PREP regulates protein phosphatase 2A (PP2A), and because GSK3b and Akt are PP2A substrates, we studied if PREP‐related lithium insensitivity is dependent on PP2A. To assess this, HEK‐293 and SH‐SY5Y cells with PREP deletion or PREP inhibition (KYP‐2047) were exposed to lithium, and thereafter, the phosphorylation levels of GSK3b and Akt were measured by Western blot. As expected, PREP deletion and inhibition blocked the lithium‐induced phosphorylation on GSK3b and Akt in both cell lines. When lithium exposure was combined with okadaic acid, a PP2A inhibitor, KYP‐2047 did not have effect on lithium‐induced GSK3b and Akt phosphorylation. Therefore, we conclude that PREP deletion or inhibition blocks the intracellular effects of lithium on GSK3b and Akt via PP2A activation. [ABSTRACT FROM AUTHOR]

Glycogen synthase kinase 3 beta (GSK3 β) plays a key role in pathologic hyper phosphorylation of tau and plays an important role in the pathogenesis of Alzheimer's disease. In the present study, we have screened a set of potential hits in in silico platform to gain insight regarding binding profile with the target (GSK3 β) from molecular docking, ADME/T, and molecular dynamics (MD) simulations. The three screened compounds 6-BIBEO, 6-BIO, and SB216763 topped the docking score chart when subjected to hard scoring function extraprecision of GLIDE. The active site dynamics study through MD simulations provides insights on residues Asp133, Val135, and Ile62 which are in a state of minimum deviation from their mean special position while they interact with the respective ligands. The same molecules also displayed favorable pharmacokinetic profile, negative Ames test and falls correctly within drug-likeliness rules. These agents can be taken forward further for the development of anti-Alzheimer's drug therapy. [ABSTRACT FROM AUTHOR]

Background: Peripheral gene expression of several molecular pathways has been studied in major depressive disorder (MDD) with promising results. We sought to investigate some of these genes in a treatment-free Latino sample of Mexican descent. Material and Methods: The sample consisted of 50 MDD treatment-free cases and 50 sex and age-matched controls. Gene expression of candidate genes of neuroplasticity (BDNF, p11, and VGF), inflammation (IL1A, IL1B, IL4, IL6, IL7, IL8, IL10, MIF, and TNFA), the canonical Wnt signaling pathway (TCF7L2, APC, and GSK3B), and mTOR, was compared in cases and controls. RNA was obtained from blood samples. We used bivariate analyses to compare subjects versus control mean mRNA quantification of target genes and lineal regression modelling to test for effects of age and body mass index on gene expression. Results: Most subjects were female (66%) with a mean age of 26.7 (SD 7.9) years. Only GSK3B was differentially expressed between cases and controls at a statistically significant level (p = 0.048). TCF7L-2 showed the highest number of correlations with MDD-related traits, yet these were modest in size. Discussion: GSK3B encodes a moderator of the canonical Wnt signaling pathway. It has a role in neuroplasticity, neuroprotection, depression, and other psychiatric phenotypes. We found that adding population diversity has the potential to elicit distinct peripheral gene expression markers in MDD and MDD-related traits. However, our results should only be considered as hypothesis-generating research that merits further replication in larger cohorts of similar ancestry. [ABSTRACT FROM AUTHOR]

Ultraviolet (UV) irradiation causes cellular oxidative stress. Under redox imbalance, Keap1-dependent Nrf2 degradation is minimal. In this study, we examined the role of Ca2+ in Nrf2 homeostasis after UVB irradiation using human dermal fibroblasts. UVB irradiation stimulates 12-lipoxygenase and the product 12-hydroxyeicosatetraenoic acid then activates TRPV1 increasing the cell's cytosolic Ca2+ concentration. UVB irradiation induced reactive oxygen species generation and apoptosis are inhibited in the absence of Ca2+ or in the presence of either a 12-lipoxygenase inhibitor or a TRPV1 inhibitor during and after UVB irradiation. Thus, the Ca2+ increase via TRPV1 is a critical factor in UVB irradiation induced oxidative stress. UVB irradiation induces a Ca2+ dependent Nrf2 degradation and thus activation of TRPV1 with 12-hydroxyeicosatetraenoic acid also decreasing Nrf2 levels. UVB irradiation induced Nrf2 degradation is inhibited by co-treatment of cells with W-7, cyclosporin A, SB-216763 or MG-132, which are inhibitors of calmodulin, calcineurin, GSK3β and the proteasome, respectively. Furthermore, UVB irradiation in parallel induces GSK3β dephosphorylation in a Ca2+ dependent manner. Co-immunoprecipitation showed that UVB irradiation induces an increase in Nrf2 phosphorylation, an increase in the binding of β-TrCP and Nrf2, and an increase in Nrf2 ubiquitination; these effects are all Ca2+ dependent. These findings suggest that UVB irradiation induced GSK3β activation in a Ca2+ dependent manner, which then stimulates the phosphorylation and ubiquitination of Nrf2 via β-TrCP. Indeed, silencing of β-TrCP was found to inhibit UVB irradiation-induced oxidative stress, Nrf2 degradation and apoptosis, while it had no effect on the Ca2+ increase. Taken together, our results suggest that a Ca2+ influx via TRPV1 is responsible for UVB irradiation-induced Nrf2 degradation and that modulation of the Ca2+-calmodulin-calcineurin-GSK3β-Nrf2-β-TrCP-Cullin-1 pathway may explain Ca2+ dependent Nrf2 degradation. Image 1 • UVB irradiation causes Ca2+ increase via TRPV1 after 12-lipoxygenase activation. • UVB irradiation induced Nrf2 degradation, ROS generation and apoptosis requires Ca2+. • Calcineurin dephosphorylates and activates GSK3β, which then phosphorylates Nrf2. • The P-Nrf2-β-TrCP complex ubiquitinates Nrf2 and targets it for proteasomal degradation. [ABSTRACT FROM AUTHOR]

Cisplatin alone or in combination with 5FU (5-fluorouracil) and docetaxel (TPF) are common regimen chemotherapeutics for treatment of advanced oral squamous cell carcinoma (OSCC). Despite the initial positive response, several patients experience relapse due to chemoresistance. The potential role of Bcl-2 antiapoptotic members in acquired chemoresistance is yet to be explored. To address this, we designed two different relevant OSCC chemoresistant models: (i) acquired chemoresistant cells, where OSCC lines were treated with conventional chemotherapy for a prolonged period to develop chemoresistance, and (ii) chemoresistant patient-derived cells, where primary cells were established from tumor of neoadjuvant-treated OSCC patients who do not respond to TPF. Among all Bcl-2 antiapoptotic members, Mcl-1 expression (but not Bcl-2 or Bcl-xL) was found to be upregulated in both chemoresistant OSCC lines and chemoresistant tumors when compared with their respective sensitive counterparts. Irrespective of all three chemotherapy drugs, Mcl-1 expression was elevated in OSCC cells that are resistant to either cisplatin or 5FU or docetaxel. In chemoresistant OSCC, Mcl-1 mRNA was upregulated by signal transducer and activator of transcription 3 (STAT3) activation, and the protein was stabilized by AKT-mediated glycogen synthase kinase 3 beta (GSK3β) inactivation. Genetic (siRNA) or pharmacological (Triptolide, a transcriptional repressor of Mcl-1) inhibition of Mcl-1 induces drug-mediated cell death in chemoresistant OSCC. In patient-derived xenograft model of advanced stage and chemoresistant OSCC tumor, Triptolide restores cisplatin-mediated cell death and facilitates significant reduction of tumor burdens. Overall, our data suggest Mcl-1 dependency of chemoresistant OSCC. A combination regimen of Mcl-1 inhibitor with conventional chemotherapy deserves further clinical investigation in advanced OSCC. [ABSTRACT FROM AUTHOR]

Background: Antipsychotics are developed to treat mental disorders in adults; however, the prescription (mostly "off-label") of antipsychotics for children/adolescents has been constantly increasing over years. The influences of antipsychotics on juveniles requires investigation to validate their clinic use. Antipsychotics mainly exert their effects via several receptors and signaling pathways.Aims: This study examined the effects of aripiprazole, olanzapine, and risperidone on selected signaling pathways, N-methyl-D-aspartate, and γ-aminobutyric acid A receptors in juveniles.Methods: Rats were orally administered aripiprazole (1 mg/kg), olanzapine (1 mg/kg), risperidone (0.3 mg/kg), or vehicle three times/day from postnatal day 23 (±1 day) for three weeks. The effects of antipsychotics in the nucleus accumbens and caudate putamen were measured by Western blots.Results: In the nucleus accumbens, all three drugs differentially increased N-methyl-D-aspartate and γ-aminobutyric acid A receptor expression. Additionally, all three antipsychotics differentially elevated the phosphorylation of glycogen synthase kinase 3 beta, β-catenin, and cAMP-responsive element-binding protein 1. In the caudate putamen, olanzapine increased β-catenin phosphorylation; and aripiprazole and olanzapine elevated γ-aminobutyric acid A receptor levels. Correlation analysis indicated that antipsychotics might modulate N-methyl-D-aspartate receptors via glycogen synthase kinase 3 beta-β-catenin signaling and/or cAMP-responsive element-binding protein 1 activation.Conclusions: These findings suggest that antipsychotics can affect protein kinase A- and glycogen synthase kinase 3 beta-dependent signaling pathways in juveniles; and their modulation on N-methyl-D-aspartate and γ-aminobutyric acid A receptors is probably through glycogen synthase kinase 3 beta-β-catenin signaling and/or cAMP-responsive element-binding protein 1 activation. [ABSTRACT FROM AUTHOR]

Background & Aims Glycogen synthase kinase 3β (Gsk3β [ Gsk3b ]) is a ubiquitously expressed kinase with distinctive functions in different types of cells. Although its roles in regulating innate immune activation and ischaemia and reperfusion injuries (IRIs) have been well documented, the underlying mechanisms remain ambiguous, in part because of the lack of cell-specific tools in vivo . Methods We created a myeloid-specific Gsk3b knockout (KO) strain to study the function of Gsk3β in macrophages in a murine liver partial warm ischaemia model. Results Compared with controls, myeloid Gsk3b KO mice were protected from IRI, with diminished proinflammatory but enhanced anti-inflammatory immune responses in livers. In bone marrow-derived macrophages, Gsk3β deficiency resulted in an early reduction of Tnf gene transcription but sustained increase of Il10 gene transcription on Toll-like receptor 4 stimulation in vitro . These effects were associated with enhanced AMP-activated protein kinase (AMPK) activation, which led to an accelerated and higher level of induction of the novel innate immune negative regulator small heterodimer partner (SHP [ Nr0b2 ]). The regulatory function of Gsk3β on AMPK activation and SHP induction was confirmed in wild-type bone marrow-derived macrophages with a Gsk3 inhibitor. Furthermore, we found that this immune regulatory mechanism was independent of Gsk3β Ser9 phosphorylation and the phosphoinositide 3-kinase–Akt signalling pathway. In vivo , myeloid Gsk3β deficiency facilitated SHP upregulation by ischaemia–reperfusion in liver macrophages. Treatment of Gsk3b KO mice with either AMPK inhibitor or SHP small interfering RNA before the onset of liver ischaemia restored liver proinflammatory immune activation and IRI in these otherwise protected hosts. Additionally, pharmacological activation of AMPK protected wild-type mice from liver IRI, with reduced proinflammatory immune activation. Inhibition of the AMPK–SHP pathway by liver ischaemia was demonstrated in tumour resection patients. Conclusions Gsk3β promotes innate proinflammatory immune activation by restraining AMPK activation. Lay summary Glycogen synthase kinase 3β promotes macrophage inflammatory activation by inhibiting the immune regulatory signalling of AMP-activated protein kinase and the induction of small heterodimer partner. Therefore, therapeutic targeting of glycogen synthase kinase 3β enhances innate immune regulation and protects liver from ischaemia and reperfusion injury. [ABSTRACT FROM AUTHOR]

Parkinson's Disease (PD) and Multiple System Atrophy (MSA) are neurodegenerative diseases characterized neuropathologically by alpha-synuclein accumulation in brain cells. This accumulation is hypothesized to contribute to constitutive neuroinflammation, and to participate in the neurodegeneration. Cytokines, which are the main inflammatory signalling molecules, have been identified in blood and cerebrospinal fluid of PD patients, but studies investigating the human brain levels are scarce. It is documented that neurotrophins, necessary for survival of brain cells and known to interact with cytokines, are altered in the basal ganglia of PD patients. In regards to MSA, no major study has investigated brain cytokine or neurotrophin protein expression. Here, we measured protein levels of 18 cytokines (IL-2, 4–8, 10, 12, 13, 17, G-CSF, GM-CSF, IFN-γ, MCP-1, MIP-1α and 1β, TNF-α) and 5 neurotrophins (BDNF, GDNF, bFGF, PDGF-BB, VEGF) in the dorsomedial prefrontal cortex in brains of MSA and PD patients and control subjects. We found altered expression of IL-2, IL-13, and G-CSF, but no differences in neurotrophin levels. Further, in MSA patients we identified increased mRNA levels of GSK3β that is involved in neuroinflammatory pathways. Lastly, we identified increased expression of the neurodegenerative marker S100B, but not CRP, in PD and MSA patients, indicating local rather than systemic inflammation. Supporting this, in both diseases we observed increased MHC class II + and CD45 + positive cells, and low numbers of infiltrating CD3 + cells. In conclusion, we identified neuroinflammatory responses in PD and MSA which seems more widespread in the brain than neurotrophic changes. [ABSTRACT FROM AUTHOR]

Transient receptor potential melastatin 2 (TRPM2), a calcium-permeable non-selective cation channel, is reported to mediate brain damage following ischemic insults in adult mice. However, the role of TRPM2 channels in neonatal hypoxic-ischemic brain injury remains unknown. We hypothesize that TRPM2 +/− and TRPM2 −/− neonatal mice have reduced hypoxic-ischemic brain injury. To study the effect of TRPM2 on neonatal brain damage, we used 2,3,5-triphenyltetrazolium chloride (TTC) staining to assess the infarct volume and whole brain imaging to assess morphological changes in the brain. In addition, we also evaluated neurobehavioral outcomes for sensorimotor function 7 days following hypoxic-ischemic brain injury. We report that the infarct volumes were significantly smaller and behavioral outcomes were improved in both TRPM2 +/− and TRPM2 −/− mice compared to that of wildtype mice. Next, we found that TRPM2-null mice showed reduced dephosphorylation of GSK-3β following hypoxic ischemic injury unlike sham mice. TRPM2 +/− and TRPM2 −/− mice also had reduced activation of astrocytes and microglia in ipsilateral hemispheres, compared to wildtype mice. These findings suggest that TRPM2 channels play an essential role in mediating hypoxic-ischemic brain injury in neonatal mice. Genetically eliminating TRPM2 channels can provide neuroprotection against hypoxic-ischemic brain injury and this effect is elicited in part through regulation of GSK-3β. [ABSTRACT FROM AUTHOR]

Synthetic triterpenoids are a class of anti-cancer compounds that target many cellular functions, including apoptosis and cell growth in both cell culture and animal models. We have shown that triterpenoids inhibit cell migration in part by interfering with Arp2/3-dependent branched actin polymerization in lamellipodia (To et al., 2010). Our current studies reveal that Glycogen Synthase Kinase 3 beta (GSK3β), a kinase that regulates many cellular processes, including cell adhesion dynamics, is a triterpenoid-binding protein. Furthermore, triterpenoids were observed to inhibit GSK3β activity and increase cellular focal adhesion size. To further examine whether these effects on focal adhesions in triterpenoid-treated cells were GSK3β-dependent, GSK3β inhibitors (lithium chloride and SB216763) were used to examine cell adhesion and morphology as well as cell migration. Our results showed that GSK3β inhibitors also altered cell adhesion sizes. Moreover, these inhibitors blocked cell migration and displaced proteins at the leading edge of migrating cells, consistent with what was observed in triterpenoid-treated cells. Therefore, the triterpenoids may affect cell migration via a mechanism that targets and alters the activity and localization of GSK3β. [ABSTRACT FROM AUTHOR]

Aryl hydrocarbon receptor (AHR), a ligand-activated transcription factor, has been studied extensively in carcinogenesis through the genomic pathway. In recent years, AHR has also been reported to exert positive or negative effects on epithelial-mesenchymal transition (EMT), the crucial step in tumor malignant progression. However, the detailed mechanism remains controversial. Analysis of AHR-expression levels in non-small cell lung cancer cell lines and lung cancer tissues revealed an inverse correlation between AHR protein levels and tumor cell invasion and metastasis. Overexpression of wild-type AHR in H1299 cells (AHR poorly expressed, potently invasive) not only accelerated mesenchymal vimentin degradation, but also prevented cell invasion in vitro and in vivo. In the absence of AHR agonists, the overexpressed AHR protein was predominantly localized in the cytoplasm, where it interacted with vimentin and functioned as an E3 ubiquitin ligase. A 6-h incubation with the proteasome inhibitor MG-132 fully rescued vimentin from AHR-mediated proteasomal degradation. In AHR-overexpressing H1299 cells, either vimentin degradation or invasive suppression could be reversed when glycogen synthase kinase 3 beta (GSK3β) was inactivated by CHIR-99021 treatment. In contrast, silencing of AHR in A549 cells (AHR highly expressed, weakly invasive) resulted in the downregulation of epithelial biomarkers (E-cadherin and claudin-1), augmentation of mesenchymal vimentin level, and GSK3β Ser-9 hyper-phosphorylation, which led to enhanced invasiveness. This work demonstrates that cytoplasmic, resting AHR protein may act as an EMT suppressor via a non-genomic pathway. Depletion of cytoplasmic AHR content represents a potential switch for EMT, thereby leading to the scattering of tumor cells. [ABSTRACT FROM AUTHOR]

Breviscapine, a standardized Chinese herbal medicine extracted from Erigeron breviscapine, has been widely used to treat cerebrovascular diseases. However, there are no reports about the neuroprotective effects and underlying molecular mechanisms of breviscapine on traumatic brain injury (TBI). Therefore, this study was aimed to investigate the effects of breviscapine on rats with TBI insult and illuminate the underlying mechanism. We created a traumatic brain-injured model with breviscapine lateral ventricle injection and evaluated the expressional changes of glycogen synthase kinase 3 beta (GSK3β) as well as the GSK3β-involved signaling pathways including apoptosis and axonal growth. At 7, 14, 21 days after injection, we found a great reduction of motor disability in TBI rats following breviscapine treatment, which was accompanied with a notably increased expression of phospho-Ser9-GSK3β (p-Ser9-GSK3β) and decreased expression of phosphor-Try216-GSK3β (p-Try216-GSK3β) at 7 days after injection. Concomitantly, an enhanced expression of synaptic marker synaptophysin (SYP) together with a weakened expression of pro-apoptotic caspase3 was observed after TBI rats were treated with breviscapine. Terminal deoxynucleotidyl transferase deoxy-UTP-nick end labeling (TUNEL) immunohistochemical assay and SYP immunofluorescence staining also confirmed the result. This study suggests that breviscapine inhibits the GSK3β signaling pathway to promote neurobehavioral function following neurotrauma. These events may provide a new insight into the mechanism of breviscapine treating brain injury. [ABSTRACT FROM AUTHOR]

The mitochondrial permeability transition pore was originally described in the 1970's as a Ca activated pore and has since been attributed to the pathogenesis of many diseases. Here we evaluate how each of the current models of the pore complex fit to what is known about how Ca regulates the pore, and any insight that provides into the molecular identity of the pore complex. We also discuss the central role of Ca in modulating the pore's open probability by directly regulating processes, such as ATP/ADP balance through the tricarboxylic acid cycle, electron transport chain, and mitochondrial membrane potential. We review how Ca influences second messengers such as reactive oxygen/nitrogen species production and polyphosphate formation. We discuss the evidence for how Ca regulates post-translational modification of cyclophilin D including phosphorylation by glycogen synthase kinase 3 beta, deacetylation by sirtuins, and oxidation/ nitrosylation of key residues. Lastly we introduce a novel view into how Ca activated proteolysis through calpains in the mitochondria may be a driver of sustained pore opening during pathologies such as ischemia reperfusion injury. [ABSTRACT FROM AUTHOR]

Podocyte injury or loss plays a major role in the pathogenesis of proteinuric kidney disease including diabetic nephropathy (DN). High basal level of autophagy is critical for podocyte health. Recent studies have revealed that hepatocyte growth factor (HGF) can ameliorate podocyte injury and proteinuria. However, little is known about the impact of HGF on podocyte autophagy. In this study, we investigated whether and how HGF affects autophagy in podocytes treated with high glucose (HG) conditions. HGF significantly diminishes apoptosis, oxidative stress and autophagy impairment inflicted by HG in podocytes. These beneficial effects of HGF disappear once HGF receptor is blocked by SU11274, a specific inhibitor of c-Met. Moreover, HGF markedly suppresses HG-stimulated glycogen synthase kinase 3beta (GSK3β) activity. Accordingly, exogenous constitutively-active GSK3β overexpression using an adenoviral vector system (Ad-GSK3β-S9A) abrogates the ability of HGF to ameliorate HG-mediated podocyte injury while neither adenoviral-mediated overexpression of wild-type GSK3β (Ad-GSK3β-WT) nor adenoviral transduction of inactive GSK3β mutant (Ad-GSK3β-K85A) can counteract the protective effects of HGF on HG-treated podocytes. Collectively, these results suggest that HGF prevents HG-induced podocyte injury via an autophagy-promoting mechanism, which involves GSK3β inhibition. [ABSTRACT FROM AUTHOR]

Chronic restraint stress (CRS) causes hippocampal neurodegeneration and hippocampus-dependent cognitive deficits. Flupirtine represents neuroprotective effects and we have previously shown that flupirtine can protect against memory impairment induced by acute stress. The present study aimed to investigate whether flupirtine could alleviate spatial learning and memory impairment and hippocampal apoptosis induced by CRS. CRS mice were restrained in well-ventilated Plexiglass tubes for 6 h daily beginning from 10:00 to 16:00 for 21 consecutive days. Mice were injected with flupirtine (10 mg/kg and 25 mg/kg) or vehicle (10% DMSO) 30 min before restraint stress for 21 days. After stressor cessation, the spatial learning and memory, dendritic spine density, injured neurons and the levels of Bcl-2, Bax, p-Akt, p-GSK-3β, p-Erk1/2 and synaptophysin of hippocampal tissues were examined. Our results showed that flupirtine significantly prevented spatial learning and memory impairment induced by CRS in the Morris water maze. In addition, flupirtine (10 mg/kg and 25 mg/kg) treatment alleviated neuronal apoptosis and the reduction of dendritic spine density and synaptophysin expression in the hippocampal CA1 region of CRS mice. Furthermore, flupirtine (10 mg/kg and 25 mg/kg) treatment significantly decreased the expression of Bax and increased the p-Akt and p-GSK-3β, and flupirtine (25 mg/kg) treatment up-regulated the p-Erk1/2 in the hippocampus of CRS mice. These results suggested that flupirtine exerted protective effects on the CRS-induced cognitive impairment and hippocampal neuronal apoptosis, which is possibly associated with the activation of Akt/GSK-3β and Erk1/2 signaling pathways. [ABSTRACT FROM AUTHOR]

Background: β-Synuclein (β-Syn) is a member of the highly homologous synuclein protein family. The most prominent family member, α-synuclein (α-Syn), abnormally accumulates in so-called Lewy bodies, one of the major pathological hallmarks of α-synucleinopathies. Notably, parts of the peptide backbone, called the nonamyloid component, are also found in amyloid plaques. However, β-Syn seems to have beneficial effects by reducing α-Syn aggregation, and amyloid antiaggregatory activity has been described. Objective: The aim of the study was to analyze if wild-type β-Syn can counteract functional and pathological changes in a murine Alzheimer model over different time periods. Methods: At the onset of pathology, lentiviral particles expressing human β-Syn were injected into the hippocampus of transgenic mice overexpressing human amyloid precursor protein with Swedish and London mutations (APPSL). An empty vector served as the control. Behavioral analyses were performed 1, 3 and 6 months after injection followed by biochemical and histological examinations of brain samples. Results: β-Syn expression was locally concentrated and rather modest, but nevertheless changed its effect on APP expression and plaque load in a time- and concentration-dependent manner. Interestingly, the phosphorylation of glycogen synthase kinase 3 beta was enhanced in APPSL mice expressing human β-Syn, but an inverse trend was observed in wild-type animals. Conclusion: The initially reported beneficial effects of β-Syn could be partially reproduced, but locally elevated levels of β-Syn might also cause neurodegeneration. To enlighten the controversial pathological mechanism of β-Syn, further examinations considering the relationship between concentration and exposure time of β-Syn are needed. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Sulforaphane (SFN), the bioactive component of cruciferous vegetables, is a potent indirect antioxidant. Oxidative stress and activation of glycogen synthase kinase 3beta (GSK3β) are two major contributors to the pathogenesis of diabetic nephropathy (DN). Here, we investigated whether and how SFN affected GSK3β in experimental models of DN in vivo and in vitro . SFN treatment obviously prevented the increase in urine albumin excretion, matrix expansion, transforming growth factor-β1 expression, fibronectin and type IV collagen deposition in the diabetic kidney. Simultaneously, the level of 8-oxo-deoxyguanosine, an indicator of oxidative damage, was markedly lowered in SFN-treated diabetic rats, together with a significant reduction in activity of the GSK-3β/Fyn axis and an evident activation of Nrf2 signaling. Similarly, antifibrotic effects of SFN, parallel to enhanced inhibitory Ser9-phosphorylation of GSK3β and Fyn/Nrf2 nuclear export/import, were observed in the cultured rat mesangial cells (RMC) exposed to high glucose. The salutary effects of SFN on high-glucose-stimulated RMC were abolished by overexpression of GSK3β while being rescued by lithium chloride, a well-known GSK3β inhibitor. Taken together, our findings suggested that SFN ameliorated experimental diabetic nephropathy, at least in part, via GSK3β/Fyn/Nrf2 signaling pathway. [ABSTRACT FROM AUTHOR]

Background: Glycogen synthase kinase 3 beta (GSK3B) is the major kinase phosphorylating tau protein. Hyperphosphorylated tau is one of the hallmarks of Alzheimer's disease (AD). Despite extensive research, the role of GSK3B in AD pathogenesis is not fully understood. Objective: To evaluate possible associations between gene variants of GSK3B and risk of AD. Methods: Twelve GSK3B tag single-nucleotide polymorphisms (SNPs), together with the previously AD-associated rs334558, were analyzed in 583 AD patients and 673 controls. Analyses on single marker and haplotype levels were done to relate to risk of AD, Mini-Mental State Examination (MMSE) scores, and cerebrospinal fluid (CSF) biomarker levels of total tau (T-tau), hyperphosphorylated tau (P-tau181), and amyloid-β (Aβ42). Results: After correction for multiple testing, we found a number of associations of gene variants with CSF biomarker levels and cognitive function in the AD patients. Firstly, rs334558 was associated with elevated T-tau levels (pc = 0.04). Next, rs1154597 showed association with reduced Aβ42 levels (pc = 0.007). Lastly, rs3107669 was associated with lower MMSE scores (pc = 0.03). In addition, one more SNP was nominally significantly associated with reduced Aβ42 levels and another was associated with reduced MMSE. Conclusion: We found GSK3B gene variants associated with cognitive function and CSF biomarkers T-tau and Aβ42. To our knowledge, this is the first time GSK3B has been associated with cognitive function or CSF biomarkers reflecting neuronal degeneration (T-tau) and brain amyloid load (Aβ42). The regulation of GSK3B needs to be investigated further, to fully understand how these GSK3B gene variants are involved in AD pathogenesis. [ABSTRACT FROM AUTHOR]

Background--Myocardial infarction-induced remodeling includes chamber dilatation, contractile dysfunction, and fibrosis. Of these, fibrosis is the least understood. After myocardial infarction, activated cardiac fibroblasts deposit extracellular matrix. Current therapies to prevent fibrosis are inadequate, and new molecular targets are needed. Methods and Results--Herein we report that glycogen synthase kinase-3β (GSK-3β) is phosphorylated (inhibited) in fibrotic tissues from ischemic human and mouse heart. Using 2 fibroblast-specific GSK-3β knockout mouse models, we show that deletion of GSK-3β in cardiac fibroblasts leads to fibrogenesis, left ventricular dysfunction, and excessive scarring in the ischemic heart. Deletion of GSK-3β induces a profibrotic myoibroblast phenotype in isolated cardiac fibroblasts, in post-myocardial infarction hearts, and in mouse embryonic fibroblasts deleted for GSK-3β. Mechanistically, GSK-3β inhibits profibrotic transforming growth factor-β1/SMAD-3 signaling via interactions with SMAD-3. Moreover, deletion of GSK-3β resulted in the significant increase of SMAD-3 transcriptional activity. This pathway is central to the pathology because a small-molecule inhibitor of SMAD-3 largely prevented fibrosis and limited left ventricular remodeling. Conclusions--These studies support targeting GSK-3β in myocardial fibrotic disorders and establish critical roles of cardiac fibroblasts in remodeling and ventricular dysfunction. [ABSTRACT FROM AUTHOR]

Background: The Wnt/β- The Wnt/(β-catenin signaling pathway is involved in many developmental processes in both fetal and adult life; its abnormalities can lead to disorders including several types of cancers and malfunction of specific cells and tissues in both animals and humans. Its role in reproductive processes has been proven. Objective: This study was designed to evaluate the expression of the key regulator of this signaling pathway GSK3-β and its presumed role in azoospermia. Materials and Methods: WNT3a protein concentration and GSK3-β gene expression levels were measured and compared between two groups of infertile men. The test groups consisted of 10 patients with obstructive and 10 nonobstructive azoospermia. The control group was selected among healthy men after vasectomies that were willing to conceive a child using a testicular biopsy technique. Samples were obtained by testicular biopsy and screened for the most common mutations (84, 86 and 255) in the SRY region before analyzing. GSK3-β gene expression was assessed quantitatively by real time-PCR. Results: The WNT3a protein concentration had no significant difference between the two test groups and controls. Expression of GSK3-β was down-regulated in nonobstructive azoospermia (3.10±0.19) compared with normal (7.12±0.39) and obstructive azoospermia (6.32±0.42) groups (p=0.001). Conclusion: Down-regulation of GSK-3 β may cause to non-obstructive azoospermia. Regulation and modification of GSK-3 βgene expression by drugs could be used as a therapeutic solution. [ABSTRACT FROM AUTHOR]

Abstract: Previous studies on the association between glycogen synthase kinase 3 beta (GSK3-β) polymorphisms (rs334558 and rs6438552) and Parkinson's disease (PD) susceptibility remained inconsistent. Thus, the goal of this study was to re-examine their exact association by a meta-analysis. All eligible studies were identified by a systematic literature search of multiple databases. Six studies (3105 cases and 4387 controls) on rs334558 and six studies (2579 cases and 4091 controls) on rs6438552 were included. The quality of these studies was generally good according to the Newcastle–Ottawa Scale (NOS). The meta-analysis showed null association between the two variants and PD susceptibility in all genetic models from the overall or Caucasian population. However, the analysis of rs334558 revealed that the risk of PD decreased in heterozygote, dominant or additive models (OR=0.60, 95% CI: 0.48, 0.74; OR=0.63, 95% CI: 0.51, 0.78; OR=0.82, 95% CI: 0.71, 0.94, respectively) from the Eastern Asian population. Moreover, the analysis on the homozygote, heterozygote, dominant or additive models suggested that rs6438552 also reduced the PD risk (OR=0.45, 95% CI: 0.24, 0.84; OR=0.62, 95% CI: 0.39, 0.97; OR=0.57, 95% CI: 0.37, 0.87; OR=0.66, 95% CI: 0.49, 0.88, respectively) in the Eastern Asian population. Together, the findings suggest that the two variants both reduced the risk of PD in the Eastern Asian subgroup but not in the overall and Caucasian populations, which should be cautiously interpreted because of limited number of included studies. [Copyright &y& Elsevier]

Abstract: Helium protects healthy myocardium against ischemia/reperfusion injury by early and late preconditioning (EPC, LPC) and postconditioning (PostC). We investigated helium-induced PostC of the hypertensive heart and enhancement by addition of LPC and EPC. We also investigated involvement of signaling kinases glycogen synthase kinase 3 beta (GSK-3β) and protein kinase C-epsilon (PKC-ε). To assess myocardial cell damage, we performed infarct size measurements in healthy Wistar Kyoto (WKY rats, n=8–9) and Spontaneous Hypertensive rats (SHR, n=8–9) subjected to 25min ischemia and 120min reperfusion. Rats inhaled 70% helium for 15min after index ischemia (PostC), combined with 15min helium 24h prior to index ischemia (LPC+PostC), a triple intervention with additional 3 short cycles of 5min helium inhalation shortly before ischemia (EPC+LPC+PostC), or no further treatment. In WKY rats, PostC reduced infarct size from 46±2% (mean±S.E.M) in the control group to 29±2%. LPC+PostC or EPC+LPC+PostC reduced infarct sizes to a similar extent (30±3% and 32±2% respectively). In SHR, EPC+LPC+PostC reduced infarct size from 53±3% in control to 39±3%, while PostC or LPC+PostC alone were not protective; infarct size 48±4% and 44±4%, respectively. Neither PostC in WKY rats nor EPC+LPC+PostC in SHR was associated with an increase in phosphorylation of GSK-3β and PKC-ε after 15min of reperfusion. Concluding, a triple intervention of helium conditioning results in cardioprotection in SHR, whereas a single intervention does not. In WKY rats, the triple intervention does not further augment protection. Helium conditioning is not associated with a mechanism involving GSK-3β and PKC-ε. [Copyright &y& Elsevier]

Abstract: Glycogen synthase kinase 3 beta (GSK3β) plays a critical role in signal transductions concerning neuronal death. In the present study, we investigated the potential role of GSK3β in 6-hydroxydopamine (6-OHDA)-induced toxicity in human neuroblastoma cell line SH-SY5Y. We assessed the apoptotic proteins and the relative levels of pGSK3β (Ser9) and pGSK3β (Tyr216) to GSK3β in 6-OHDA-treated SH-SY5Y. Furthermore, we downregulated the expression of GSK3β by short hairpin RNA (shRNA) interference and compared the cell viability and expression of apoptotic proteins in knockdown group with those in control group under the treatment of 6-OHDA. We found that 6-OHDA increased the expression of caspase-3 and caspase-9 but not caspase-8. Additionally, 6-OHDA decreased the ratio of pGSK3β (Ser9)/GSK3β and increased the ratio of pGSK3β (Tyr216)/GSK3β. Moreover, 6-OHDA induced less cell viability loss and lower expression of caspase-9 and caspase-3 in GSK3β knockdown group compared with control. The present data indicate that 6-OHDA may induce apoptosis in SH-SY5Y via the intrinsic death pathway and GSK3β knockdown can partly attenuate 6-OHDA-induced neuronal death and apoptosis, suggesting that GSK3β may have the potential to serve as a therapeutic target for PD. [ABSTRACT FROM AUTHOR]

Tumor necrosis factor related apoptosis inducing ligand (TRAIL) is involved in amyloid beta dependent neurotoxicity via the extrinsic pathway. Recently, several genes modulating TRAIL cytotoxicity have been characterized, providing evidence for a role of wingless-type mouse mammary tumor virus integration site family (Wnt), Jun-N-terminal kinase and other pathways in increased cell susceptibility to the cytokine. We investigated whether neurotoxic effects of TRAIL could be due to modulation of the Wnt signaling pathway. Western blot analysis of Wnt in SH-SY5Y human neuroblastoma cells showed significantly decreased Wnt expression in cultures treated with TRAIL. Correspondingly, both phosphorylation of glycogen synthase kinase 3 beta and degradation of cytoplasmic β-catenin were increased, as well as phosphorylation of the τ protein, bringing about the picture of neuronal damage. As a counterproof of the interaction of TRAIL with the Wnt pathway, the addition of the specific glycogen synthase kinase 3 beta inhibitor SB216763 resulted in rescue of a significant percent of cells from TRAIL-induced apoptosis. The rescue was total when the caspase 8 inhibitor z-IETD-FMK was added in combination with SB216763. Results show that, probably, in addition to triggering caspase signaling, TRAIL also interferes with the Wnt pathway, additionally concurring to neuronal damage. These data suggest that the Wnt pathway substantially contributes to the TRAIL-related neurotoxicity and indicate the TRAIL system as a candidate target for pharmacological treatment of Alzheimer’s disease and related disorders. [ABSTRACT FROM AUTHOR]

Podocyte loss is a detrimental feature and major cause of proteinuria in diabetic nephropathy (DN). Our previous study revealed that hepatocyte growth factor (HGF) prevented high glucose-induced podocyte injury via enhancing autophagy. In the current study, we aimed to assess the role of HGF on podocyte homeostasis in DN and clarify its mechanisms further. Diabetic mice treated with HGF had markedly reduced ratio of kidney weight to body weight, urinary albumin excretion, podocyte loss and matrix expansion compared with that in the non-treated counterpart. Simultaneously, HGF-treated diabetic mice exhibited increased autophagy activity as indicated by the decreased accumulation of sequestosome 1 (SQSTM1/ p62) and increased microtubule-associated proteins 1 light chains 3 (LC3) II/LC3I ratio. These beneficial effects of HGF were blocked by HGF/c-Met inhibitor Crizotinib or phosphatidylinositide 3-kinases (PI3K) inhibitor LY294002. Moreover, HGF treatment obviously prevented inactivation of the protein kinase B (Akt)-glycogen synthase kinase 3 beta (GSK3β)-transcription factor EB (TFEB) axis in high glucose-stimulated podocytes, which was associated with improved lysosome function and autophagy. Accordingly, adenovirus vector encoding constitutively active GSK3β (Ad-GSK3β-S9A) offset whereas small interfering RNA against GSK3β (GSK3β siRNA) recapitulated salutary effects of HGF on lysosome number and autophagy in podocytes. These results suggested that HGF protected against diabetic nephropathy through restoring podocyte autophagy, which at least partially involved PI3K/Akt-GSK3β-TFEB axis-mediated lysosomal function improvement. • HGF protects against diabetic nephropathy through restoring podocyte autophagy. • HGF improves lysosome function by enhancing TFEB nuclear translocation and GSK3β activity inhibition. • Targeting PI3K-GSK3β-TFEB axis may have therapeutic potential for autophagic dysfunction diseases. [ABSTRACT FROM AUTHOR]

Mutations in desmosomal genes linked to arrhythmogenic cardiomyopathy are commonly associated with Wnt/β-catenin signaling abnormalities and reduction of the sodium current density. Inhibitors of GSK3B were reported to restore sodium current and improve heart function in various arrhythmogenic cardiomyopathy models, but mechanisms underlying this effect remain unclear. We hypothesized that there is a crosstalk between desmosomal proteins, signaling pathways, and cardiac sodium channels. To reveal molecular mechanisms of arrhythmogenic cardiomyopathy, we established human iPSC-based model of this pathology. iPSC-derived cardiomyocytes from patient carrying two genetic variants in PKP2 gene demonstrated that PKP2 haploinsufficiency due to frameshift variant, in combination with the missense variant expressed from the second allele, was associated with decreased Wnt/β-catenin activity and reduced sodium current. Different approaches were tested to restore impaired cardiomyocytes functions, including wild type PKP2 transduction, GSK3B inhibition and Wnt/β-catenin signaling modulation. Inhibition of GSK3B led to the restoration of both Wnt/β-catenin signaling activity and sodium current density in patient-specific cardiomyocytes while GSK3B activation led to the reduction of sodium current density. Moreover, we found that upon inhibition GSK3B sodium current was restored through Wnt/β-catenin-independent mechanism. We propose that alterations in GSK3B-Wnt/β-catenin signaling pathways lead to regulation of sodium current implying its role in molecular pathogenesis of arrhythmogenic cardiomyopathy. Unlabelled Image • PKP2 genetic variants are associated with decreased Wnt/β-catenin activity and reduced sodium current density • Inhibition of GSK3B restores both Wnt/β-catenin signaling activity and sodium current density • GSK3B activation leads to the reduction of sodium current density • Inhibition of GSK3B restores sodium current density through Wnt/β-catenin-independent mechanism [ABSTRACT FROM AUTHOR]

Background: Obesity impairs a variety of cell types including adipose-derived mesenchymal stem cells (ASCs). ASCs are indispensable for tissue homeostasis/repair, immunomodulation, and cell renewal. It has been demonstrated that obese ASCs are defective in differentiation, motility, immunomodulation, and replication. We have recently reported that some of these defects are linked to impaired primary cilia, which are unable to properly convey and coordinate a variety of signaling pathways. We hypothesized that the rescue of the primary cilium in obese ASCs would restore their functional properties. Methods: Obese ASCs derived from subcutaneous and visceral adipose tissues were treated with a specific inhibitor against Aurora A or with an inhibitor against extracellular signal-regulated kinase 1/2 (Erk1/2). Multiple molecular and cellular assays were performed to analyze the altered functionalities and their involved pathways. Results: The treatment with low doses of these inhibitors extended the length of the primary cilium, restored the invasion and migration potential, and improved the differentiation capacity of obese ASCs. Associated with enhanced differentiation ability, the cells displayed an increased expression of self-renewal/stemness-related genes like SOX2, OCT4, and NANOG, mediated by reduced active glycogen synthase kinase 3 β (GSK3β). Conclusion: This work describes a novel phenomenon whereby the primary cilium of obese ASCs is rescuable by the low-dose inhibition of Aurora A or Erk1/2, restoring functional ASCs with increased stemness. These cells might be able to improve tissue homeostasis in obese patients and thereby ameliorate obesity-associated diseases. Additionally, these functionally restored obese ASCs could be useful for novel autologous mesenchymal stem cell-based therapies. [ABSTRACT FROM AUTHOR]