Reduced expression of hippocampal GluN2A-NMDAR increases seizure susceptibility and causes deficits in contextual memory

N-methyl-D-aspartate receptors are heterotetramers composed of two GluN1 obligatory subunits and two regulatory subunits. In cognitive-related brain structures, GluN2A and GluN2B are the most abundant regulatory subunits, and their expression is subjected to tight regulation. During development, GluN2B expression is characteristic of immature synapses, whereas GluN2A is present in mature ones. This change in expression induces a shift in GluN2A/GluN2B ratio known as developmental switch. Moreover, modifications in this relationship have been associated with learning and memory, as well as different pathologies. In this work, we used a specific shRNA to induce a reduction in GluN2A expression after the developmental switch, both in vitro in primary cultured hippocampal neurons and in vivo in adult male Wistar rats. After in vitro characterization, we performed a cognitive profile and evaluated seizure susceptibility in vivo. Our in vitro results showed that the decrease in the expression of GluN2A changes GluN2A/GluN2B ratio without altering the expression of other regulatory subunits. Moreover, rats expressing the anti-GluN2A shRNA in vivo displayed an impaired contextual fear-conditioning memory. In addition, these animals showed increased seizure susceptibility, in terms of both time and intensity, which led us to conclude that deregulation in GluN2A expression at the hippocampus is associated with seizure susceptibility and learning–memory mechanisms.Fil: Acutain, Maria Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; ArgentinaFil: Griebler Luft, Jordana. Universidade Federal do Rio Grande do Sul; BrasilFil: Vázquez, Cecilia Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; ArgentinaFil: Popik, Bruno. Universidade Federal do Rio Grande do Sul; BrasilFil: Cercato, Magalí Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; ArgentinaFil: Epstein, Alberto. Universite Lyon 2; FranciaFil: Salvetti, Anna. Inserm; FranciaFil: Jerusalinsky, Diana Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; ArgentinaFil: de Oliveira Alvares, Lucas. Universidade Federal do Rio Grande do Sul; BrasilFil: Baez, Maria Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; Argentin

CARACTERIZAÇÃO DE UM MODELO DE PARALISIA CEREBRAL EM RATOS: COGNIÇÃO E ESTRUTURA DO HIPOCAMPO E AMÍGDALA

Fundamento - A paralisia cerebral (PC) é caracterizada por distúrbios do movimento e da postura, que podem estar associados a déficits cognitivos. Tais comprometimentos são atribuídos a lesões não pro- gressivas ao encéfalo em desenvolvimento. No âmbito experimental, modelos animais dessa condição clínica capazes de reproduzir o fe- nótipo e as alterações estruturais vistas em humanos são escassos. Objetivo - Investigar as repercussões da indução de um modelo de PC sobre a função cognitiva e estrutura do hipocampo e amígdala em ratos Wistar. Métodos - Dois grupos experimentais foram utilizados:Controle - filhotes de ratas injetadas com solução salina durante a gestação (n=8) e 2) Paralisia cerebral - filhotes de ratas injetadas com Lipopolissacarídeo (LPS) durante a gestação (n=8), submetidos à anóxia perinatal e restrição sensório-motora durante 30 dias. A memória espacial dos animais foi avaliada pela tarefa de reconhe- cimento da localização de objetos, enquanto o comportamento do tipo ansioso foi verificado pelo teste de labirinto em cruz elevado. Após a avaliação comportamental, os animais foram eutanasiados e os encéfalos dissecados para posterior processamento histológico. Resultados - O grupo PC presentou déficits de memória espacial e uma redução do número de neurônios granulares no giro denteado. Entretanto o comportamento do tipo ansioso e a histologia do núcleo central e complexo basolateral da amígdala foram semelhantes entre os grupos. Conclusão - Como observado em parte dos pacientes com PC, este modelo experimental prejudica a memória dependente do hipocampo. Entretanto, a combinação de intervenções não alterou a ansiedade e estrutura da amígdala

X4 Human Immunodeficiency Virus Type 1 gp120 Promotes Human Hepatic Stellate Cell Activation and Collagen I Expression through Interactions with CXCR4

<div><h3>Background & Aims</h3><p>Patients coinfected with HIV-1 and HCV develop more rapid liver fibrosis than patients monoinfected with HCV. HIV RNA levels correlate with fibrosis progression implicating HIV directly in the fibrotic process. While activated hepatic stellate cells (HSCs) express the 2 major HIV chemokine coreceptors, CXCR4 and CCR5, little is known about the pro-fibrogenic effects of the HIV-1 envelope protein, gp120, on HSCs. We therefore examined the <em>in vitro</em> impact of X4 gp120 on HSC activation, collagen I expression, and underlying signaling pathways and examined the <em>in vivo</em> expression of gp120 in HIV/HCV coinfected livers.</p> <h3>Methods</h3><p>Primary human HSCs and LX-2 cells, a human HSC line, were challenged with X4 gp120 and expression of fibrogenic markers assessed by qRT-PCR and Western blot +/− either CXCR4-targeted shRNA or anti-CXCR4 neutralizing antibody. Downstream intracellular signaling pathways were evaluated with Western blot and pre-treatment with specific pathway inhibitors. Gp120 immunostaining was performed on HIV/HCV coinfected liver biopsies.</p> <h3>Results</h3><p>X4 gp 120 significantly increased expression of alpha-smooth muscle actin (a-SMA) and collagen I in HSCs which was blocked by pre-incubation with either CXCR4-targeted shRNA or anti-CXCR4 neutralizing antibody. Furthermore, X4 gp120 promoted Extracellular signal-regulated kinase (ERK) 1/2 phosphorylation and pretreatment with an ERK inhibitor attenuated HSC activation and collagen I expression. Sinusoidal staining for gp120 was evident in HIV/HCV coinfected livers.</p> <h3>Conclusions</h3><p>X4 HIV-1 gp120 is pro-fibrogenic through its interactions with CXCR4 on activated HSCs. The availability of small molecule inhibitors to CXCR4 make this a potential anti-fibrotic target in HIV/HCV coinfected patients.</p> </div

Boletín oficial de la provincia de Santander: Número 147 - 1908 Septiembre 14

As calpaínas são proteases dependentes de cálcio e amplamente expressas em duas isoformas no encéfalo, calpaína-1 e calpaína-2. Uma das suas principais atividades resulta na modulação dos espinhos dendríticos, através da reorganização do citoesqueleto de actina e da degradação do córtex celular, principalmente da espectrina. Outra consequência da sua atividade é a endocitose de receptores glutamatérgicos (NMDA e AMPA), constituindo assim, um correlato para a formação e manutenção da memória. Então, testamos se a inibição farmacológica da calpaína no hipocampo dorsal afeta a consolidação, evocação e reconsolidação da memória aversiva em ratos Wistar machos. Assim, utilizamos o condicionamento aversivo contextual (CAC) para avaliar as memórias aversivas e um antagonista seletivo para ambas as isoformas da calpaína (PD150606) para estudar a sua função. Primeiro mostramos que a infusão imediatamente pós-treino do inibidor da calpaína PD150606 prejudicou a consolidação da memória de longo prazo, mas não a memória de curto prazo. Em seguida, mostramos que a infusão pré-teste do inibidor de calpaína inibiu completamente a evocação da memória. Finalmente, o bloqueio da atividade da calpaína após a reativação da memória acarretou em um prejuízo na reconsolidação. Em conjunto, nossos resultados mostraram que a calpaína desempenha um papel essencial no hipocampo, que contribui significativamente para a formação, expressão e reconsolidação da memória.Calpains are calcium-dependent proteases and are extensively expressed in two isoforms in the brain, calpain-1 and calpain-2. One of its main activities results in the modulation of dendritic spines by the reorganization of the actin cytoskeleton and the cellular cortex by degradation of spectrin. Another consequence of its activity is endocytosis of glutamatergic receptors (NMDA and AMPA), thus constituting a correlate for memory formation and maintenance. We tested whether the pharmacological inhibition of calpain in the dorsal hippocampus affects the consolidation, retrieval and reconsolidation of aversive memory in male Wistar rats. Thus, we used contextual fear conditioning (CFC) to evaluate aversive memories and a selective antagonist for both calpain isoforms (PD150606) to study its function. We first showed that the immediate post-training infusion of the PD150606 calpain inhibitor impaired long-term memory consolidation, but not short-term memory. Next, we showed that the pre-test infusion of the calpain inhibitor expressively inhibited memory retrieval. Finally, blocking calpain activity after memory reactivation disrupted reconsolidation. Taken together, our results shown that calpain plays an essential role in the hippocampus by enabling memory formation, expression, and reconsolidation

Effects of the lercanidipine - Enalapril combination vs. The corresponding monotherapies on home blood pressure in hypertension: Evidence from a large database

103siObjective: To compare a combination of a dihydropyridine calcium-channel blocker with an angiotensin converting enzyme inhibitor vs. monotherapy with one or the other drug and placebo for their effects on home blood pressure (HBP). Methods: After a 2-week placebo wash-out, patients with an elevated office blood pressure (BP) (diastolic 100–109 and systolic <180 mmHg) and HBP (diastolic 85 mmHg) were randomized double-blind to a 10-week treatment with placebo, lercanidipine, 10 or 20mg daily, enalapril, 10 or 20mg daily, or the four possible combinations. In addition to office BP, HBP was self-measured via a validated semiautomatic device twice in the morning and twice in the evening during the 7 days before randomization and at the end of treatment. Baseline and treatment HBP values were separately averaged for each day, morning, evening or the whole monitoring period, excluding the first day. Day-by-day HBP variability was defined as the SD or the variation coefficient of the daily BP averages. Results: Eight hundred and fifty-four patients with valid HBP recordings at baseline and at the end of treatment were analyzed (intention-to-treat population). From the baseline value (147.011.6 mmHg) systolic/diastolic HBP showed a small reduction (average baseline-adjusted change: –1.8/–1.6 mmHg) with placebo, a more marked significant fall with monotherapies (8.8/5.9 mmHg, P<0.001/<0.001 vs. placebo) and even more with combination treatment (11.6/7.6 mmHg, P<0.001/ <0.001 vs. placebo and P<0.01/<0.05 vs. monotherapy). A similar pattern was observed for each of the days of the BP self-monitoring period as well as for either morning or evening values, although the difference between mono and combination treatment appeared to be consistently significant for the morning values only. Dayby- day systolic BP-SD was unaffected by placebo and slightly reduced by drug treatments, with no, however, significant changes in SBP-variation coefficient. Baseline and end of treatment HBP values showed a limited correlation with office BP values, this being particularly the case for treatment-induced changes (correlation coefficients: 0.37 for systolic and 0.45 for diastolic BP). Conclusion: This large HBP database shows that the lercanidipine–enalapril combination lowers HBP more effectively than the corresponding monotherapies and placebo, and that this greater effect is consistent between days.reservedmixedMancia, Giuseppe; Omboni, Stefano; Chazova, Irina; Coca, Antonio; Girerd, Xavier; Haller, Hermann; Parati, Gianfranco; Pauletto, Paolo; Pupek-Musialik, Danuta; Svyshchenko, Yevgeniya; Boye, Alain; Charrier, Bruno; Couffin, Yvon; Marmor, Philippe; Marty, Jacques; Navarre, Jean Louis; Ansari, Anwar; Büttner, Claudia; Kropp, Maximilian; Mehling, Heidrun; Paschen, Christine; Schenkenberger, Isabelle; Schneider, Helmut; Sperling, Karsten; Stübler, Petra; Von Behren, Volker; Lembo, Giuseppe; Scanferla, Flavio; Sechi, Leonardo Alberto; Gębala, Andrzej; Hoffmann, Andrzej; Janik, Krzysztof; Klimza-Masłowska, Anna; Kaczmarek, Barbara; Koźminski, Piotr; Makowiecka-Cies̈la, Magdalena; Mordaka, Robert; Nowakowski, Tomasz; Pasternak, Dariusz; Skibińska, Elzbieta; Sulik, Piotr; Szpajer, Michał; Walczewska, Jolanta; Zaczek, Marcin; Zienciuk-Krajka, Agnieszka; Alexeeva, Nadezhda; Bokarev, Igor; Chazova, Iina; Conrady, Alexandra; Emelyanov, Alexander; Galustyan, Anna; Idrisova, Elena; Khasanov, Niyaz; Khokhlov, Alexander; Libov, Igor; Reshetko, Olga; Sokurenko, German; Stryuk, Raisa; Tereshchenko, Sergey; Trofimov, Vasily; Zrazhevsky, Konstantin; Carlos Calvo, S.; De Teresa, Luis; Ferre, Raimon; García, Juan; Gil, Apolonia; Gil, Blas; Montenegro, Jesús; Oliván, Josefina; Ortiz, Jacinto; Pascual, José María; Rivera, Antonio; De Quevedo, José Antonio Sainz; Zúñiga, Manuel; Martinez, Valentin; Pujol, Montserrat; Bazylevych, Andriy; Gyrina, Olga; Ignatenko, Grygoriy; Kazymyrko, Vitaly; Khomazyuk, Tetyana; Kononenko, Lyudmyla; Korzh, Oleksii; Kovalenko, Volodymyr; Kuryata, Oleksander; Kushnir, Mykola; Lishnevska, Viktoriia; Lymar, Iurii; Ostrovska, Lidiia; Popik, Galyna; Rudyk, Yuriy; Shershnyova, Oxana; Sierkova, Valentyna; Storozhuk, Borys; Tseluyko, Vira; Vatutin, Mykola; Vayda, Myroslava; Vizir, Vadym; Volkov, Volodymyr; Voloshyna, Olena; Yagensky, Andriy; Zhurba, Svitlana; Zorin, ValeriiMancia, Giuseppe; Omboni, Stefano; Chazova, Irina; Coca, Antonio; Girerd, Xavier; Haller, Hermann; Parati, Gianfranco; Pauletto, Paolo; Pupek Musialik, Danuta; Svyshchenko, Yevgeniya; Boye, Alain; Charrier, Bruno; Couffin, Yvon; Marmor, Philippe; Marty, Jacques; Navarre, Jean Louis; Ansari, Anwar; Büttner, Claudia; Kropp, Maximilian; Mehling, Heidrun; Paschen, Christine; Schenkenberger, Isabelle; Schneider, Helmut; Sperling, Karsten; Stübler, Petra; Von Behren, Volker; Lembo, Giuseppe; Scanferla, Flavio; Sechi, Leonardo Alberto; Gębala, Andrzej; Hoffmann, Andrzej; Janik, Krzysztof; Klimza Masłowska, Anna; Kaczmarek, Barbara; Koźminski, Piotr; Makowiecka Cies̈la, Magdalena; Mordaka, Robert; Nowakowski, Tomasz; Pasternak, Dariusz; Skibińska, Elzbieta; Sulik, Piotr; Szpajer, Michał; Walczewska, Jolanta; Zaczek, Marcin; Zienciuk Krajka, Agnieszka; Alexeeva, Nadezhda; Bokarev, Igor; Chazova, Iina; Conrady, Alexandra; Emelyanov, Alexander; Galustyan, Anna; Idrisova, Elena; Khasanov, Niyaz; Khokhlov, Alexander; Libov, Igor; Reshetko, Olga; Sokurenko, German; Stryuk, Raisa; Tereshchenko, Sergey; Trofimov, Vasily; Zrazhevsky, Konstantin; Carlos Calvo, S.; De Teresa, Luis; Ferre, Raimon; García, Juan; Gil, Apolonia; Gil, Blas; Montenegro, Jesús; Oliván, Josefina; Ortiz, Jacinto; Pascual, José María; Rivera, Antonio; De Quevedo, José Antonio Sainz; Zúñiga, Manuel; Martinez, Valentin; Pujol, Montserrat; Bazylevych, Andriy; Gyrina, Olga; Ignatenko, Grygoriy; Kazymyrko, Vitaly; Khomazyuk, Tetyana; Kononenko, Lyudmyla; Korzh, Oleksii; Kovalenko, Volodymyr; Kuryata, Oleksander; Kushnir, Mykola; Lishnevska, Viktoriia; Lymar, Iurii; Ostrovska, Lidiia; Popik, Galyna; Rudyk, Yuriy; Shershnyova, Oxana; Sierkova, Valentyna; Storozhuk, Borys; Tseluyko, Vira; Vatutin, Mykola; Vayda, Myroslava; Vizir, Vadym; Volkov, Volodymyr; Voloshyna, Olena; Yagensky, Andriy; Zhurba, Svitlana; Zorin, Valeri