Micro and macro geographical analysis of Y-chromosome lineages in South Iberia.

In this study, we intend to identify the evolutionary footprints of the South Iberian population focusing on the Berber and Arab influence, which has received little attention in the literature. Analysis of the Y-chromosome variation represents a convenient way to assess the genetic contribution of North African populations to the present-day South Iberian genetic pool and could help to reconstruct other demographic events that could have influenced on that region. A total of 26 Y-SNPs and 17 Y-STRs were genotyped in 144 samples from 26 different districts of South Iberia in order to assess the male genetic composition and the level of substructure of male lineages in this area. To obtain a more comprehensive picture of the genetic structure of the South Iberian region as a whole, our data were compared with published data on neighboring populations. Our analyses allow us to confirm the specific impact of the Arab and Berber expansion and dominion of the Peninsula. Nevertheless, our results suggest that this influence is not bigger in Andalusia than in other Iberian populations.

Neuroprotective effect of osmotin against ethanol-induced apoptotic neurodegeneration in the developing rat brain.

Fetal alcohol syndrome is a neurological and developmental disorder caused by exposure of developing brain to ethanol. Administration of osmotin to rat pups reduced ethanol-induced apoptosis in cortical and hippocampal neurons. Osmotin, a plant protein, mitigated the ethanol-induced increases in cytochrome c, cleaved caspase-3, and PARP-1. Osmotin and ethanol reduced ethanol neurotoxicity both in vivo and in vitro by reducing the protein levels of cleaved caspase-3, intracellular [Ca(2+)]cyt, and mitochondrial transmembrane potential collapse, and also upregulated antiapoptotic Bcl-2 protein. Osmotin is a homolog of adiponectin, and it controls energy metabolism via phosphorylation. Adiponectin can protect hippocampal neurons against ethanol-induced apoptosis. Abrogation of signaling via receptors AdipoR1 or AdipoR2, by transfection with siRNAs, reduced the ability of osmotin and adiponectin to protect neurons against ethanol-induced neurodegeneration. Metformin, an activator of AMPK (adenosine monophosphate-activated protein kinase), increased whereas Compound C, an inhibitor of AMPK pathway, reduced the ability of osmotin and adiponectin to protect against ethanol-induced apoptosis. Osmotin exerted its neuroprotection via Bcl-2 family proteins and activation of AMPK signaling pathway. Modulation of AMPK pathways by osmotin, adiponectin, and metformin hold promise as a preventive therapy for fetal alcohol syndrome.

Vitamin C protects against ethanol and PTZ-induced apoptotic neurodegeneration in prenatal rat hippocampal neurons.

Exposure to alcohol during brain development may cause a neurological syndrome called fetal alcohol syndrome, characterized by pre- and postnatal growth deficiencies, craniofacial anomalies, and evidence of CNS dysfunction. The objective of this study was to evaluate pentylenetetrazol (PTZ) and ethanol effects on Bax, Bcl-2 expression, which further induced activation of caspase-3, release of cytochrome-c from mitochondria, and to observe the protective effects of vitamin C (vit-C) against PTZ and ethanol-induced apoptotic neurodegeneration in primary-cultured neuronal cells at gestational day 17.5. Apoptotic neurodegeneration and neuroprotective effect of vit-C were measured by using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide assay, Western blot analysis, which further conformed by the measurement of mitochondrial membrane potential using JC-1 detection kit and immunofluorescence analysis. The results showed that PTZ and ethanol produced extensive Bax-dependent caspase-9 and caspase-3 activation and caused neuronal apoptosis. Furthermore, the cotreatment of vit-C along with ethanol and PTZ showed significantly decreased expression of Bax, caspase-9, caspase-3, cytochrome-c, and significantly increased expression of antiapoptotic Bcl-2 protein when compared with control group. Our findings indicate that PTZ and ethanol activate an intrinsic apoptotic death program in neurons that is likely to contribute to the neuropathologic effects in fetal alcohol exposure, and vit-C can prevent some of the deleterious effects of PTZ and ethanol on the developing brain. The available experimental evidence and the safety of vit-C in pregnancy suggest the experimental use of ascorbic acid as a new and effective protective agent ethanol and PTZ-induced apoptotic neurodegeneration.

siRNA-mediated GABA(B) receptor at early fetal rat brain upon acute and chronic ethanol exposure: down regulation of PKA and p-CREB expression.

To observe the modulatory role of GABA(B1)R upon ethanol's effect during early brain development, we studied the effects of chronic maternal (10% ethanol during pregnancy) and acute (in vitro) ethanol exposure on the neuronal protein kinase A (PKA-α) and phosphorylation of cAMP-response element binding protein (p-CREB), using a system where GABA(B1)R were specifically knocked down in the primary cells cultured at gestational day (GD) 12.5. The results showed that upon acute and chronic ethanol treatment the GABA(B1)R expression was decreased and further decreased when GABA(B1)R was transfection with siRNA, while increased upon exposure of baclofen, and baclofen plus phaclofen treatment. PKA expression was also decreased with acute and chronic ethanol treatment, whereas it showed increase upon exposure of baclofen and baclofen with phaclofen. Furthermore, intracellular Ca(2+) concentration was increased upon ethanol, baclofen, phaclofen exposure but showed decrease in GABA(B1)R siRNA group. Finally, these effects could lead to changes of p-CREB expression, which showed same expression pattern as PKA. We speculate that GABA(B)R activity upon ethanol exposure could modulate intracellular calcium homeostasis and the expressional changes of PKA and p-CREB, which cause various negative effects on fetal brain development and modulation of GABA(B)R upon ethanol exposure may underlying cause of ethanol's effects.

Neuroprotective effect of vitamin C against the ethanol and nicotine modulation of GABA(B) receptor and PKA-alpha expression in prenatal rat brain.

Prenatal ethanol exposure has various deleterious effects on neuronal development and can induce various defects in developing brain, resulting in fetal alcohol syndrome (FAS). gamma-Aminobutyric acid (GABA(B)) receptor (R) is known to play an important role during the development of the central nervous system (CNS). Our study was designed to investigate the effect of ethanol (100 mM), nicotine (50 microM) (for 30 min and 1 h), vitamin C (vitC, 0.5 mM), ethanol plus vitC, and nicotine plus vitC on expression level of GABA(B1), GABA(B2)R, and protein kinase A-alpha (PKA) in prenatal rat cortical and hippocampal neurons at gestational days (GD) 17.5. The results showed that, upon ethanol and nicotine exposure, GABA(B1) and GABA(B2)R protein expression increased significantly in the cortex and hippocampus for a short (30 min) and long term (1 h), whereas only GABA(B2)R subunit was decreased upon nicotine exposure for a long term in the cortex. Furthermore, PKA expression in cortex and hippocampus increased with ethanol exposure during short term, whereas long-term exposure results increased in cortex and decreased in hippocampus. Moreover, the cotreatment of vitC with ethanol and nicotine showed significantly decreased expression of GABA(B1), GABA(B2)R, and PKA in cortex and hippocampus for a long-term exposure. Mitochondrial membrane potential, Fluoro-jade-B, and propidium iodide staining were used to elucidate possible neurodegeneration. Our results suggest the involvement of GABA(B)R and PKA in nicotine and ethanol-mediated neurodevelopmental defects and the potential use of vitC as a effective protective agent for FAS-related deficits.

Ethanol and PTZ effects on siRNA-mediated GABAB1 receptor: down regulation of intracellular signaling pathway in prenatal rat cortical and hippocampal neurons.

GABA(B) receptors (R) are widely expressed and distributed in the nervous system, and have been implicated in variety of neurodegenerative and pathophysiological disorders. However, the exact molecular mechanism regarding responsibility of GABA(B1)R in downstream signaling pathway is not well understood. The present study was undertaken to explore the downstream signaling and role of GABA(B1)R upon acute ethanol and pentylenetetrazol (PTZ) exposure for (20 min) in cortical and hippocampal neuronal cell cultures by using GABA(B1)R RNA interference (i) (30 nM, 48 h) at gestational days 17.5. The results showed that GABA(B1)R and protein kinase A-alpha (PKA) showed decreased expression upon ethanol and PTZ exposure in cortical and hippocampal neurons during transfected and nontransfected conditions, whereas these effects could lead to significant changes in phosphorylation of cAMP-response element binding protein (p-CREB) expression where GABA(B1)R was knocked down. Furthermore, intracellular Ca(+2) concentrations were also reduced in some groups after transfection with GABA(B1)R RNAi. These results showed a critical role of GABA(B1)R upon ethanol and PTZ exposure by modulating downstream signaling pathway. Finally, these findings suggested that inhibition of GABA(B1)R results in the modulation of PKA, p-CREB pathway may play a role in long-term changes in the nervous system, and may be an underlying cause of ethanol's effects.

In vivo and in vitro ethanol exposure in prenatal rat brain: GABA(B) receptor modulation on dopamine D(1) receptor and protein kinase A.

We have investigated the effects of prenatal ethanol exposure on GABA(B) receptors (GABA(B)Rs), protein kinase A (PKA), and DA D(1) receptor (DAD(1)R) expressions. GABA(B1)R and GABA(B2)R showed different age-dependent expressions in in vivo fetal rat forebrain from gestational days (GD) 15.5 to 21.5 upon 10% ethanol treatment to mother, with and without baclofen at a dose of 10 mg/kg body weight/day. The protein level changes could not be attributed to changes in the level of transcription since GABA(B)R mRNA presented different expression patterns upon in vivo ethanol treatment. Using in vitro cultivated cortical neurons from GD 17.5 fetuses, we also explored the modulatory effects of ethanol on PKA and DAD(1)R through GABA(B)Rs, under 50 microM baclofen and 100 microM phaclofen administrations, with or without 100 mM of ethanol treatment in the culture media. The results showed that 20 min ethanol treatment without baclofen or phaclofen had increasing effects on both the GABA(B)Rs. Further, baclofen and phaclofen administration significantly affected PKA and GABA(B)R levels upon 20 min and 1 h ethanol treatment. In contrast, DAD(1)R showed increasing effects upon ethanol treatment, which was modulated by GABA(B)R's agonist baclofen and antagonist phaclofen. Therefore the present study suggested that the GABA(B)R activity could modulate ethanol's cellular effects, which possibly including PKA and DAD(1)R activities, and may be an underlying cause of ethanol's effects.