Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P10415 (Bcl-2)
 33,771 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Activin is a member of the transforming growth factor-beta superfamily which comprises a growing list of multifunctional proteins that function as modulators of cell proliferation, differentiation, hormone secretion and neuronal survival. This study examined the neuroprotective effect of both Activin A and B in serum withdrawal and oxidative stress apoptotic cellular models and investigated the expression of pro- and anti-apoptotic proteins, which may account for the mechanism of Activin-induced neuroprotection. Here, we report that recombinant Activin A and B are neuroprotective against serum deprivation- and toxin- [either the parkinsonism-inducing neurotoxin, 6-hydroxydopamine (6-OHDA) or the peroxynitrite donor, 3-(4-morpholinyl) sydnonimine hydrochloride (SIN-1)] induced neuronal death in human SH-SY5Y neuroblastoma cells. Furthermore, we demonstrate for the first time that transient transfection with Activin betaA or betaB significantly protect SH-SY5Y and rat pheochromocytoma PC12 cells against serum withdrawal-induced apoptosis. This survival effect is mediated by the Bcl-2 family members and involves inhibition of caspase-3 activation; reduction of cleaved poly-ADP ribose polymerase and phosphorylated H2A.X protein levels and elevation of tyrosine hydroxylase expression. These results indicate that both Activin-A and -B share the potential to induce neuroprotective activity and thus may have positive impact on aging and neurodegenerative diseases to retard the accelerated rate of neuronal degeneration.
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PMID:The neuroprotective effect of Activin A and B: implication for neurodegenerative diseases. 1768 Sep 97

Our previous studies show that lymphocytes express tyrosine hydroxylase (TH) and synthesize catecholamines (CAs) including dopamine, epinephrine and norepinephrine, and that the lymphocytes-derived endogenous CAs affect function of lymphocytes via autocrine/paracrine pathways. Over recent years, induction of apoptosis has been suggested to be a possible mechanism underlying the endogenous CAs-mediated lymphocyte proliferation, differentiation and activation. However, direct effect of the lymphocytes-synthesized CAs on lymphocyte apoptosis is less known. In the present study, TH inhibitor alpha-methyl-p-tyrosine (alpha-MT) and monoamine oxydase inhibitor pargyline were employed to block the synthesis and degradation of CAs in lymphocytes activated by concanavalin A (Con A). Apoptotic cells and apoptosis-related genes and proteins, Bax, Bcl-2, Fas, Fas-Ligand (FasL) and caspase-3, were examined in the lymphocytes treated with alpha-MT or pargyline by means of Annexin V/propidium iodide (PI) staining, real-time PCR and Western blot analyses, respectively. The treatment with alpha-MT of 10(-6) M and 10(-5) M (not 10(-7) M) notably reduced intracellular and supernatant DA, E and NE of the Con A-activated lymphocytes in a dose-dependent manner, and correspondingly, the treatment induced a remarkable decrease of apoptotic lymphocytes but not necrotic cells. The expression of Bax, Fas, FasL and caspase-3 mRNAs and proteins was significantly inhibited in the Con A-activated lymphocytes after the cells were treated with alpha-MT of 10(-6) M and 10(-5) M; but the expression of Bcl-2 mRNA and protein was dramatically increased by the alpha-MT treatment. Contrarily, the treatment with pargyline of 10(-6) M and 10(-5) M (not 10(-7) M) evidently increased the intracellular and supernatant DA, E and NE contents of the Con A-activated lymphocytes in a dose-dependent manner, and meanwhile, it caused a striking increase of apoptotic lymphocytes but not necrotic cells. The expression of Bax, Fas, FasL and caspase-3 mRNAs and proteins in the Con A-stimulated lymphocytes was remarkably enhanced by the treatment with pargyline of 10(-6) M and 10(-5) M, but the expression of Bcl-2 mRNA and protein was notably attenuated by the pargyline treatment. These results imply that endogenous CAs synthesized and secreted by lymphocytes accelerate lymphocyte apoptosis by altering fine balance between the expression of antiapoptotic and proapoptotic markers at transcriptional and translational levels, and suggest that both the death receptor pathway and the mitochondrial pathway are involved in the endogenous CAs-induced apoptosis.
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PMID:Effect of endogenous catecholamines on apoptosis of Con A-activated lymphocytes of rats. 1792 Jun 95

Emerging evidence suggests beneficial effects of estrogen and estrogen-like chemicals on neurodegenerative diseases, especially Parkinson's disease (PD). Genistein, an isoflavone naturally found in soy products, displays estrogenic properties. The present study aims to investigate the neuroprotective effects of genistein on dopaminergic neurons in ovariectomized (OVX), 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD model mice. MPTP significantly decreased the levels of dopamine (DA) and its metabolites dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the striatum, which could be restored by genistein or estrogen pretreatment. MPTP-challenge with genistein or estrogen pretreatment demonstrated reduced neurotoxicity, with tyrosine hydroxylase-immunoreactive (TH-IR) neurons in the substantia nigra pars compacta (SNpc) affected to a significantly lesser extent as compared to the MPTP treated control. The reverse transcription-PCR results also confirmed that the MPTP-induced downregulation of TH, dopamine transporter (DAT) and Bcl-2 mRNA expression in the midbrain could be restored by genistein or estrogen pretreatment. These findings provide the first evidence that genistein has neuroprotective effects on dopaminergic neurons in the MPTP-induced PD mice and this effect may be attributed to enhancing Bcl-2 gene expression.
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PMID:Neuroprotective effects of genistein on dopaminergic neurons in the mice model of Parkinson's disease. 1805 4

Paraquat (PQ) causes selective degeneration of dopaminergic neurons in the substantia nigra pars compacta, reproducing an important pathological feature of Parkinson disease. Oxidative stress, c-Jun N-terminal kinase activation, and alpha-synuclein aggregation are each induced by PQ, but details of the cell death mechanisms involved remain unclear. We have identified a Bak-dependent cell death mechanism that is required for PQ-induced neurotoxicity. PQ induced morphological and biochemical features that were consistent with apoptosis, including dose-dependent cytochrome c release, with subsequent caspase-3 and poly(ADP-ribose) polymerase cleavage. Changes in nuclear morphology and loss of viability were blocked by cycloheximide, caspase inhibitor, and Bcl-2 overexpression. Evaluation of Bcl-2 family members showed that PQ induced high levels of Bak, Bid, BNip3, and Noxa. Small interfering RNA-mediated knockdown of BNip3, Noxa, and Bak each protected cells from PQ, but Bax knockdown did not. Finally, we tested the sensitivity of Bak-deficient mice and found them to be resistant to PQ treatments that depleted tyrosine hydroxylase immuno-positive neurons in the substantia nigra pars compacta of wild-type mice.
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PMID:Paraquat neurotoxicity is mediated by a Bak-dependent mechanism. 1805 1

The neurotrophic actions of pituitary adenylate cyclase-activating polypeptide (PACAP)-38 and leukemia inhibitory factor (LIF) were investigated in human neuroblastoma SH-SY5Y cells. Effects on differentiation were assessed through monitoring morphological changes and Western blot analysis of the expression of neuronal marker proteins. In contrast to PACAP-38, which induced a 5.5-fold increase in the number of neurite-bearing cells, LIF had no significant effect on cell morphology compared to control cells over the 4-day time course. Cells co-treated with PACAP-38+LIF showed a similar increase in neurite-bearing cells compared to those treated with PACAP-38 alone. Cell morphology was similar for PACAP-38-treated and PACAP-38+LIF-co-treated cells, with the formation of bipolar neuron-like cells with long thin neurites, topped by growth cone-like structures and varicosities. SH-SY5Y cells express tyrosine hydroxylase (TH) but only low levels of the neuronal marker proteins: Bcl-2, GAP-43 and choline acetyltransferase (ChAT). Treatment of cells with PACAP-38 induced the expression of Bcl-2, GAP-43, and ChAT but did not appear to alter the expression of TH. LIF failed to induce the expression of GAP-43 and had little effect on the expression of TH, but did induce the expression of Bcl-2 and upregulated the expression of ChAT. Co-treatment with LIF had no effect on PACAP-38-induced expression of Bcl-2, GAP-43, and ChAT. Cells differentiated for 4 days with PACAP-38 or treated with LIF also displayed increased resistance to hypoxic conditions and to treatment with H2O2 and TNFalpha. The increased resistance to hypoxic conditions for PACAP-differentiated cells was blocked by the p38 MAP kinase inhibitor, SB203580, but not by the MEK1 inhibitor, PD98059. Additionally, cell proliferation assays show that LIF, but not PACAP-38, stimulates proliferation of SH-SY5Y cells, and this observed increase by LIF is not attenuated by co-treatment with PACAP. Further investigation of the intracellular signaling pathways mediating the neurotrophic effects of PACAP on SH-SY5Y cells indicate that neither phospholipase C activation nor Ca2+/calmodulin-dependent kinase II (CAMKII) are involved.
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PMID:Neurotrophic actions of PACAP-38 and LIF on human neuroblastoma SH-SY5Y cells. 1850 35

To study character of effect of apoptosis signal proteins on activities of neurosecretory cells and neurons of rat hypothalamus, pharmacologic inhibitors of proapoptotic protein p53 Pifithrin-alpha and antiapoptotic protein Bcl-2 HA14-1 were injected into the hypothalamus. Activation of vasopressinergic neurosecretory cells at administration of the blocker Bcl-2 HA14-1 was shown: there were observed an increase of vasopressin mRNA in neurons of hypothalamus supraoptical and paraventricular nuclei, a decrease of the immunoreactive vasopressin content in posterior pituitary, and reduction of diuresis. Inactivation of p53 inhibited release of vasopressin from hypothalamus cell bodies, which is indicated by an elevated content of immunoreactive vasopressin in neurosecretory cell bodies with its unchanged synthesis, a decrease of the neurohormone content in the posterior pituitary, and an increase of diuresis rate. Activation of vasopressinergic neurons of the suprachiasmatic nucleus was also shown. Administration of the blocker Bcl-2 has been revealed to decrease functional activity both of dopaminergic neurons (Zona Incerta) and of dopaminergic neurosecretory cells (arcuate nucleus), in which a decrease of the tyrosine hydroxylase content was observed. The p53 inactivation also led to a decrease of activity of dopaminergic neurosecretory cells of arcuate nucleus, whereas activity of the proteins Zone Incerta did not change. Thus, it has been shown that a change of the apoptotic protein content in vasopressinergic and dopaminergic neurons and neurosecretory cells leads to a change of their functional activity, the character and possibly mechanisms of effects of apoptotic proteins on activities of vasopressin- and dopaminergic cells being different.
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PMID:[Effect of apoptosis proteins on function of vasopressin- and dopaminergic hypothalamic neurons]. 1872 20

In the central nervous system, fibroblast growth factor (FGF)-20 has been reported to act preferentially on midbrain dopaminergic neurons. It also promotes the dopaminergic differentiation of stem cells. We have analyzed the effects of FGF-20 on human embryonic stem cells (hESCs) differentiation into dopaminergic neurons. We induced neuronal differentiation of hESCs by co-culturing those with PA6 mouse stromal cells for 3 weeks. When we supplemented the culture medium with FGF-20, the number of tyrosine hydroxylase (TH)-expressing neurons increased fivefold, from 3% to 15% of the hESC-derived cells. The cultured cells also expressed other midbrain dopaminergic markers (PITX3, En1, Msx1, and Aldh1), suggesting that some had differentiated into midbrain dopaminergic neurons. We observed no effect of FGF-20 on the size of the soma area or neurite length of the TH-immunopositive neurons. Regardless of whether FGF-20 had been added or not, 17% of the hESC-derived cells expressed the pan-neuronal marker b-III-Tubulin. The proportion of proliferating cells positive for Ki-67 was also not affected by FGF-20 (7% of the hESC-derived cells). By contrast, after 3 weeks in culture FGF-20 significantly reduced the proportion of cells undergoing cell death, as revealed by immunoreactivity for cleaved caspase-8, Bcl-2 associated X protein (BAX) and cleaved caspase-3 (2.5% to 1.2% of cleaved caspase-3-positive cells out of the hESC-derived cells). Taken together, our results indicate that FGF-20 specifically increases the yield of dopaminergic neurons from hESCs grown on PA6 feeder cells and at least part of this effect is due to a reduction in cell death.
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PMID:Fibroblast growth factor-20 increases the yield of midbrain dopaminergic neurons derived from human embryonic stem cells. 1895 98

As a result of the progressive decrease in efficacy of drugs used to treat Parkinson's disease (PD) and the rapid development of motor complications, effective alternative treatments for PD are required. In a 6-hydroxydopamine (6-OHDA)-induced Parkinson's rat model, intracerebral peripheral blood stem cell (CD34(+)) (PBSC) transplantation significantly protected dopaminergic neurons from 6-OHDA-induced neurotoxicity, enhanced neural repair of tyrosine hydroxylase neurons through up-regulation of Bcl-2, facilitated stem cell plasticity, and attenuated activation of microglia, in comparison with vehicle-control rats. The 6-OHDA-lesioned hemi-Parkinsonian rats receiving intrastriatal transplantation of PBSCs also showed: 1) enhanced glucose metabolism in the lesioned striatum and thalamus, demonstrated by [(18)F]fluoro-2-deoxyglucose positron emission tomography (FDG-PET), 2) improved neurochemical activity as shown by proton magnetic resonance spectroscopy ((1)H-MRS), and 3) significantly reduced rotational behavior in comparison with control lesioned rats. These observations might be explained by an up-regulation of growth-associated protein 43 (GAP-43) expression because improvements in neurological dysfunction were blocked by injection of MK-801 in the PBSC-treated group. In addition, a significant increase in neurotrophic factor expression was found in the ipsilateral hemisphere of the PBSC-treated group. In summary, this protocol may be a useful strategy for the treatment of clinical PD.
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PMID:Induction of GAP-43 modulates neuroplasticity in PBSC (CD34+) implanted-Parkinson's model. 1923 91

Cyanide is a potent neurotoxicant that can produce dopaminergic neuronal death in the substantia nigra and is associated with a Parkinson-like syndrome. In this study involvement of Bcl-2/adenovirus E1B 19-kDa interacting protein 3 (BNIP3), a BH3-only Bcl-2 protein, in cyanide-induced death of dopaminergic cells was determined in mice and Mes 23.5 cells. Treatment of mice with cyanide up-regulated BNIP3 and Bax expression in tyrosine hydroxylase (TH)-positive cells of the substantia nigra, and progressive loss of TH-positive neurons was observed over a 9-day period. In Mes 23.5 dopaminergic cells, cyanide stimulated translocalization of BNIP3 to both endoplasmic reticulum (ER) and mitochondria. In ER, BNIP3 stimulated release of Ca(2+) into the cytosol, followed by accumulation of mitochondrial Ca(2+), resulting in reduction of mitochondrial membrane potential (Deltapsi(m)) and eventually cell death. Cyanide also activated Bax to colocalize with BNIP3 in ER and mitochondria. Forced overexpression of BNIP3 activated Bax, whereas gene silencing reduced Bax activity. Knockdown of Bax expression by small interfering RNA blocked the BNIP3-mediated changes in ER and mitochondrial Ca(2+) to block cyanide-induced mitochondrial dysfunction and cell death. These findings show that BNIP3-mediates cyanide-induced dopaminergic cell death through a Bax downstream signal that mobilizes ER Ca(2+) stores, followed by mitochondrial Ca(2+) overload.
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PMID:Cyanide-induced apoptosis of dopaminergic cells is promoted by BNIP3 and Bax modulation of endoplasmic reticulum-mitochondrial Ca2+ levels. 1984 71

The present work was conducted to investigate the antioxidant activity and neuroprotective effects of Tripterygium regelii extract (TRE) on H(2)O(2)-induced apoptosis in human dopaminergic cells, SH-SY5Y. TRE possessed considerable amounts of phenolics (282.73 mg tannic acid equivalents/g of extract) and flavonoids (101.43 mg naringin equivalents/g of extract). IC(50) values for reducing power and DPPH radical scavenging activity were 52.51 and 47.83 microg, respectively. The H(2)O(2) scavenging capacity of TRE was found to be 57.68 microM x microg(-1) min(-1). By examining the effects of TRE on SH-SY5Y cells injured by H(2)O(2), we found that after incubation of cells with TRE prior to H(2)O(2) exposure, the H(2)O(2) induced cytotoxicity was significantly reversed and the apoptotic features such as change in cellular morphology, nuclear condensation and DNA fragmentation was inhibited. Moreover, TRE was very effective attenuating the disruption of mitochondrial membrane potential and apoptotic cell death induced by H(2)O(2). TRE extract effectively suppressed the up-regulation of Bax, Caspase-3 and -9, and down-regulation of Bcl-2. Moreover, TRE pretreatment evidently increased the tyrosine hydroxylase (TH) and brain-derived neurotrophic factor (BDNF) in SH-SY5Y cells. These findings demonstrate that TRE protects SH-SY5Y cells against H(2)O(2)-induced injury and antioxidant properties may account for its neuroprotective actions and suggest that TRE might potentially serve as an agent for prevention of neurodegenerative disease associated with oxidative stress.
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PMID:Antioxidant activity and protective effects of Tripterygium regelii extract on hydrogen peroxide-induced injury in human dopaminergic cells, SH-SY5Y. 2046 94


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