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Exposure to ethanol during developmental stages leads to several types of neurological disorders. Apoptotic neurodegeneration due to ethanol exposure is a main feature in alcoholism. Exposure of developing animals to alcohol induces apoptotic neuronal death and causes fetal alcohol syndrome. In the present study, we observed the possible protective effect of pyruvate against ethanol-induced neurodegeneration. Exposure of developing mice to ethanol (2.5 g/kg) induces apoptotic neurodegeneration and widespread neuronal cell death in the cortex and thalamus. Co-treatment of pyruvate (500 mg/kg) protects neuronal cell against ethanol by the reduced expression of caspase-3 in these brain regions. Immunohistochemical analysis and TUNNEL at 24 h showed that apoptotic cell death induced by ethanol in the cortex and thalamus is reduced by pyruvate. Histomorphological analysis at 24 h with cresyl violet staining also proved that pyruvate reduced the number of neuronal cell loss in the cortex and thalamus. The results showed that ethanol increased the expression of caspase-3 and thus induced apoptotic neurodegeneration in the developing mice cortex and thalamus, while co-treatment of pyruvate inhibits the induction of caspase-3 and reduced the cell death in these brain regions. These findings, therefore, showed that treatment of pyruvate inhibits ethanol-induced neuronal cell loss in the postnatal seven (P7) developing mice brain and may appear as a safe neuroprotectant for treating neurodegenerative disorders in newborns and infants.

Here, we investigated the possible involvement of gamma-aminobutyric acid B1 receptor (GABAB1R) in mediating the protective effects of black soybean anthocyanins against ethanol-induced apoptosis in prenatal hippocampal neurons because GABARs are known to play an important role in the development of central nervous system. Treatments were performed on primary cultures of prenatal rat hippocampal neurons transfected with or without GABAB1R small interfering RNA (siRNA). The results showed that, when ethanol treatment was followed by anthocyanins treatment, cellular levels of proapoptotic proteins such as Bax, activated caspase-3, and cleaved poly (ADP-ribose) polymerase 1 (PARP-1) were decreased, and the cellular level of the antiapoptotic protein Bcl-2 was increased compared to treatment with ethanol alone. Furthermore, the effects of ethanol on cellular levels of GABAB1R and its downstream signaling molecules such as protein kinase A, calcium/calmodulin-dependent protein kinase II (CaMKII), and phosphorylated cAMP response element binding protein were diminished or reversed by anthocyanins treatment. The ability of anthocyanins to reverse the effects of ethanol on cellular levels of Bax, Bcl-2, active caspase-3, cleaved PARP-1, GABAB1R, and CaMKII were abrogated in cells transfected with GABAB1R siRNA. In a GABAB1R-dependent manner, anthocyanins also inhibited the ability of ethanol to elevate intracellular free Ca(2+) level and increase the proportion of cells with low mitochondrial membrane potential in the population. Cell apoptosis assay and morphological studies also confirmed the neuroprotective effect of anthocyanins against ethanol via GABAB1R. Our data suggest that GABAB1R plays an important role in the neuroprotective effects of anthocyanins against ethanol.

The Rho GTPases are the sub-group of Ras super family and identified in all eukaryotes. The Rho GTPases effect different cellular signaling pathways involved in a number of diseases such as cancer, neurological and cardiovascular disorders. Members of Rho GTPases including RhoA, RhoC and Rac1 play a major role in regulation of apoptosis in different kind of stress conditions. Here we investigated the Rho GTPase activating protein 15 (ArhGAP15) gene knock-down effect on apoptosis induced by ethanol in bovine fibroblast cells. The bovine Fibroblast cells were treated and transfected with two different concentrations (50 and 100 nM) of ArhGAP15 siRNA for 48 h respectively. Both concentrations of siRNA were effective and the results of RT-PCR revealed an efficient knock-down of ArhGAP15 mRNA in fibroblast cells. Further, the normal cells exposed to a 100 mM ethanol concentration showed a reduction in cell viability and induced the ratio of apoptosis related Bax/Bcl-2 proteins compared with ArhGAP15 siRNA transfected ethanol treated cells. Ethanol also increased caspase-3 expression in normal fibroblast cells compared with transfected cells. The ArhGAP15 knock-down cells treated with ethanol decreased Bax/Bcl-2 ratio and lower caspase-3 protein levels in ArhGAP15 knocked-down cells. Our results suggest that apoptosis induced by ethanol involves the activation of Rho GTPase activating protein 15 and silencing of the said gene protects apoptosis.

Background: Exposure to ethanol during early development triggers severe neuronal death by activating multiple stress pathways and causes neurological disorders, such as fetal alcohol effects or fetal alcohol syndrome. This study investigated the effect of ethanol on intracellular events that predispose developing neurons for apoptosis via calcium-mediated signaling. Although the underlying molecular mechanisms of ethanol neurotoxicity are not completely determined, mitochondrial dysfunction, altered calcium homeostasis and apoptosis-related proteins have been implicated in ethanol neurotoxicity. The present study was designed to evaluate the neuroprotective mechanisms of metformin (Met) and thymoquinone (TQ) during ethanol toxicity in rat prenatal cortical neurons at gestational day (GD) 17.5., Results: We found that Met and TQ, separately and synergistically, increased cell viability after ethanol (100 mM) exposure for 12 hours and attenuated the elevation of cytosolic free calcium [Ca²⁺]c. Furthermore, Met and TQ maintained normal physiological mitochondrial transmembrane potential (ΔψM), which is typically lowered by ethanol exposure. Increased cytosolic free [Ca²⁺]c and lowered mitochondrial transmembrane potential after ethanol exposure significantly decreased the expression of a key anti-apoptotic protein (Bcl-2), increased expression of Bax, and stimulated the release of cytochrome-c from mitochondria. Met and TQ treatment inhibited the apoptotic cascade by increasing Bcl-2 expression. These compounds also repressed the activation of caspase-9 and caspase-3 and reduced the cleavage of PARP-1. Morphological conformation of cell death was assessed by TUNEL, Fluoro-Jade-B, and PI staining. These staining methods demonstrated more cell death after ethanol treatment, while Met, TQ or Met plus TQ prevented ethanol-induced apoptotic cell death., Conclusion: These findings suggested that Met and TQ are strong protective agents against ethanol-induced neuronal apoptosis in primary rat cortical neurons. The collective data demonstrated that Met and TQ have the potential to ameliorate ethanol neurotoxicity and revealed a possible protective target mechanism for the damaging effects of ethanol during early brain development.

Exposure to alcohol during the early stages of brain development can lead to neurological disorders in the CNS. Apoptotic neurodegeneration due to ethanol exposure is a main feature of alcoholism. Exposure of developing animals to alcohol (during the growth spurt period in particular) elicits apoptotic neuronal death and causes fetal alcohol effects (FAE) or fetal alcohol syndrome (FAS). A single episode of ethanol intoxication (at 5 g/kg) in a seven-day-old developing rat can activate the apoptotic cascade, leading to widespread neuronal death in the brain. In the present study, we investigated the potential protective effect of pyruvate against ethanol-induced neuroapoptosis. After 4h, a single dose of ethanol induced upregulation of Bax, release of mitochondrial cytochrome-c into the cytosol, activation of caspase-3 and cleavage of poly (ADP-ribose) polymerase (PARP-1), all of which promote apoptosis. These effects were all reversed by co-treatment with pyruvate at a well-tolerated dosage (1000 mg/kg). Histopathology performed at 24 and 48 h with Fluoro-Jade-B and cresyl violet stains showed that pyruvate significantly reduced the number of dead cells in the cerebral cortex, hippocampus and thalamus. Immunohistochemical analysis at 24h confirmed that ethanol-induced cell death is both apoptotic and inhibited by pyruvate. These findings suggest that pyruvate treatment attenuates ethanol-induced neuronal cell loss in the developing rat brain and holds promise as a safe therapeutic and neuroprotective agent in the treatment of neurodegenerative disorders in newborns and infants., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The present study was designed to observe the effect of PTZ on expression of caspsae-3, and to evaluate the neuroprotective role of vitamin C (vit-C) against PTZ-induced apoptotic neurodegeneration in adult rat brain. We observed that administration of a single conclusive dose of pentylenetetrazol (PTZ 50mg/kg) in adults rats induced epileptic seizure and increased activation of caspase-3 and caused neuronal death. Further, rats were injected with vit-C (250 mg/kg) 30 min before PTZ injection. The protective effect of vit-C against PTZ-induced apoptotic neurodegeneration in adult rat brain was observed using Western blot analysis and Nissl staining. The results showed that conclusive dose of PTZ-induced seizure, increased expression of caspase-3 and neuronal apoptosis in adult rat brain. Whereas, the pretreatment of vit-C along with PTZ showed significantly decreased expression of caspase-3 as compare to control group. Finally, our results indicated that vit-C can prevent some of the deleterious effect of seizure and neuronal degeneration induced by PTZ in adult rat brain.

Background: Exposure to the chemotherapeutic alkylating agent thiotepa during brain development leads to neurological complications arising from neurodegeneration and irreversible damage to the developing central nerve system (CNS). Administration of single dose of thiotepa in 7-d postnatal (P7) rat triggers activation of apoptotic cascade and widespread neuronal death. The present study was aimed to elucidate whether nicotinamide may prevent thiotepa-induced neurodegeneration in the developing rat brain., Methodology/principal Findings: Neuronal cell death induced by thiotepa was associated with the induction of Bax, release of cytochrome-c from mitochondria into the cytosol, activation of caspase-3 and cleavage of poly (ADP-ribose) polymerase (PARP-1). Post-treatment of developing rats with nicotinamide suppressed thiotepa-induced upregulation of Bax, reduced cytochrome-c release into the cytosol and reduced expression of activated caspase-3 and cleavage of PARP-1. Cresyl violet staining showed numerous dead cells in the cortex hippocampus and thalamus; post-treatment with nicotinamide reduced the number of dead cells in these brain regions. Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labeling (TUNEL) and immunohistochemical analysis of caspase-3 show that thiotepa-induced cell death is apoptotic and that it is inhibited by nicotinamide treatment., Conclusion: Nicotinamide (Nic) treatment with thiotepa significantly improved neuronal survival and alleviated neuronal cell death in the developing rat. These data demonstrate that nicotinamide shows promise as a therapeutic and neuroprotective agent for the treatment of neurodegenerative disorders in newborns and infants.

Background: Cell death and differentiations are the critical processes in developing fetal brain, where ethanol induces lots of changes in gene expression patterns of fetal nervous system leading to fetal alcohol syndrome (FAS). The objective of the present study was to observe whether maternal ethanol exposure can alter gene expression pattern in mother and in fetus during mid and late prenatal stage., Material/methods: 10% ethanol was orally applied to female Spraque-Dawley rats and fetuses were sacrificed on gestational day (GD) 19.5 and 21.5. Total mRNA was isolated for differential-display PCR (DD-PCR) and sequence was analyzed to find out the homologous gene(s) using GenBank database of the BLAST program. Finally, the gene expression pattern in different maternal and fetal brain areas of the control and the ethanol treated groups were studied by RNase protection assay (RPA) and in situ hybridization., Results: Out of several differentially expressed genes, apoptosis-related RNA binding protein (RBP), 'Napor-3' mRNA expression was significantly inhibited by ethanol in fetal rat fore-, mid- and hind- brain, and adult rat cortex and hippocampus when compared with the untreated control. The cDNA analysis was further supported our result (accession: AF090697, 95% sequence homology)., Conclusions: The age and area dependent suppression of apoptosis-related RBP, Napor-3 gene expression in proliferating fetal brain by maternal ethanol suggesting high susceptibility towards ethanol intake at the time of neuronal cell development and proliferation. Further, ethanol also affects maternal brain tissues that may be one of the reasons for ethanol-induce irreversible damage of the developing brain. The present study for the first time provides the evidence that Napor-3 suppression by ethanol during mid and late stage fetal brain converts natural physiological event apoptosis into pathological process, which may be useful as a novel therapeutic approach towards FAS-associated developmental brain damage as a consequence of maternal drinking behavior.

Development of effective agents for treatment of hormone-refractory prostate cancer (HRPC) has become a national medical priority. D-Allose is a monosaccharide (C-3 epimer of glucose) distributed rarely in nature; because of its scarcity and cost, the biological effect has hardly been studied. In the present study, we demonstrated the inhibitory action of D-allose on proliferation of human HRPC cell lines, DU145 and PC-3 in a dose- and time-dependent manner, while human normal prostate epithelial (NPE) cell line, PrEC showed no remarkable effect. In vitro treatment of D-allose resulted in the alteration of Bcl-2/Bax ratio in favor of apoptosis (programmed cell death, PCD) in both the HRPC cell lines, which was associated with the lowering of mitochondrial transmembrane potential (Deltapsi(m)) and the release of cytochrome C (cyt C), the cleavage of caspase 3 and poly (ADP-ribose) polymerase (PARP), and the elevation of calcium concentration in cytosol ([Ca(2+)](c)). D-Allose also induced G1 phase arrest of the cell cycle in DU145 cell line. This study for the first time suggested the antiproliferative effect of D-allose through induction of PCD in HRPC cell lines, which could be due to the modulation of mitochondria mediated intrinsic apoptotic pathway.

Background: The forkhead factor, FOXO3a, is known to induce apoptosis in endothelial cells (ECs). However, its effects on extracellular matrices (ECM), which are important in EC survival, remained unknown. Here, we evaluated the role of FOXO3a on EC-ECM interaction., Methods and Results: Constitutively active FOXO3a was transduced to human umbilical vein endothelial cells by adenoviral vector (Ad-TM-FOXO3a). Ad-TM-FOXO3a transfection led to dehiscence of ECs from fibronectin-coated plates, resulting in anoikis, which was significantly reversed by matrix metalloproteinase (MMP) inhibitor, GM6001. FOXO3a increased the expression of MMP-3 (stromelysin-1) but decreased the expression of tissue inhibitors of metalloproteinases-1 (TIMP-1), which was associated with increased MMP enzymatic activity in zymography. Pathophysiologic conditions such as serum starvation or heat shock also induced activation of endogenous FOXO3a, leading to activation of MMP-3 and apoptosis, which was reversed by GM6001. Delivery of Ad-TM-FOXO3a to the intraluminal surface in vivo led to EC denudation, disrupted vascular integrity, and impaired endothelium-dependent vasorelaxation., Conclusions: Activation of MMPs and possible ECM disruption represent novel mechanisms of FOXO3a-mediated apoptosis in ECs.

Objective: We evaluated the full range effects of FOXO3a in endothelial cells (ECs) by microarray analysis and investigated the role of FOXO3a regulating TNF receptor signaling pathway., Methods and Results: Human umbilical vein endothelial cells (HUVECs) were transfected with adenoviral vectors expressing constitutively active FOXO3a (Ad-TM-FOXO3a). Ad-TM-FOXO3a transfection caused remarkable apoptosis, which were accompanied with upregulation of genes related with TNF receptor signaling, such as TNF-alpha, TANK (TRAF-associated NF-kappaB activator), and TTRAP (TRAF and TNF receptor-associated protein). Furthermore, kappaB-Ras1 (IkappaB-interacting Ras-like protein-1) which is known to block IkappaB degradation was found increased, and intranuclear translocation of NF-kappaB was inhibited. GADD45beta and XIAP, negative regulators of c-Jun N-terminal kinase (JNK), were suppressed and JNK activity was increased. Attenuation of TNF signaling pathway either by blocking antibody for TNF receptor or by blocking JNK with DMAP (6-dimethylaminopurine) or Ad-TAM67 (dominant negative c-Jun) cotransfection, significantly reduced FOXO3a-induced apoptosis. Finally, treatment of vasculature with heat shock, an activator of endogenous FOXO3a, resulted in EC apoptosis, which was completely rescued by Ad-TAM67., Conclusions: FOXO3a promotes apoptosis of ECs, through activation of JNK and suppression of NF-kappaB. These data identify a novel role of FOXO3a to turn TNF receptor signaling to a proapoptotic JNK-dependent pathway.

AKAP12 (A-Kinase anchoring protein 12) is a protein kinase C substrate and a potential tumor suppressor. AKAP12 is down-regulated by several oncogenes and strongly suppressed in various cancers including prostate, ovarian and breast cancers. AKAP12 acts as a regulator of mitogenesis by anchoring key signal proteins such as PKA, PKC, and cyclins. In this study, AKAP12 was found to suppress tumor cell viability by inducing apoptosis via caspase-3 in HT1080 cells. This AKAP12-induced apoptosis was associated with a decreased expression of Bcl-2 and increased expression of Bax. Moreover, AKAP12-transfectant strongly induced the expression of Cip1/p21 and Kip1/p27, but resulted in a decrease in cyclin D1 involved in G(1) progression. Accordingly, these results suggest that AKAP12 may play an important role in tumor growth suppression by inducing apoptosis with the regulation of multiple molecules in the cell cycle progression.