RESUMO
Physical exercise has been shown to have an impact on memory and hippocampal function across different age groups. Nevertheless, the influence and mechanisms underlying how voluntary exercise during puberty affects memory are still inadequately comprehended. This research aims to examine the impacts of self-initiated physical activity throughout adolescence on spatial memory. Developing mice were exposed to a 4-wk voluntary wheel running exercise protocol, commencing at the age of 30 d. After engaging in voluntary wheel running exercise during development, there was an enhancement in spatial memory. Moreover, hippocampal dentate gyrus and CA3 neurons rather than CA1 neurons exhibited an increase in the miniature excitatory postsynaptic currents and miniature inhibitory postsynaptic currents. In addition, there was an increase in the expression of NR2A/NR2B subunits of N-methyl-D-aspartate receptors and α1GABAA subunit of gamma-aminobutyric acid type A receptors, as well as dendritic spine density, specifically within dentate gyrus and CA3 regions rather than CA1 region. The findings suggest that voluntary exercise during development can enhance spatial memory in mice by increasing synapse numbers and improving synaptic transmission in hippocampal dentate gyrus and CA3 regions, but not in CA1 region. This study sheds light on the neural mechanisms underlying how early-life exercise improves cognitive function.
Assuntos
Giro Denteado , Memória Espacial , Camundongos , Animais , Giro Denteado/metabolismo , Atividade Motora , Maturidade Sexual , Hipocampo/metabolismo , Transmissão Sináptica/fisiologiaRESUMO
The pre-transmetalation intermediates are critically important in Suzuki-Miyaura cross-coupling (SMC) reactions and have become a hot spot of the current research. However, the pre-transmetalation intermediates under base-free conditions have not been clear. Herein, a comprehensive theoretical study is performed on the base-free Pd-catalyzed desulfonative SMC reaction. The fragile coordination feature and the acceleration role of the RuPhos chelate ligand are revealed. The hydrogen-bond complex between the Pd-F complex and aryl boronic acid is identified as an important pre-transmetalation intermediate, which increases the energy span to 32.5 kcal/mol. The controlling factor for the formation of the hydrogen-bond complexes is attributed to the electronegativities of halogen atoms in the metal halide complexes. What is more, other reported SMC reaction systems involving metal halide complexes and aryl boronic acids are reconsidered and suggest that the hydrogen-bond complexes widely exist as stable pre-transmetalation intermediates with influencing the catalytic activities. The earth-abundant Ni-catalyzed desulfonative SMC reaction is further designed and predicted to have a higher activity than the original Pd-catalyzed SMC reaction.
RESUMO
The industrial production of methanol through CO hydrogenation using the Cu/ZnO/Al2O3 catalyst requires harsh conditions, and the development of new catalysts with low operating temperatures is highly desirable. In this study, organic biomimetic FLP catalysts with good tolerance to CO poison are theoretically designed. The base-free catalytic reaction contains the 1,1-addition of CO into a formic acid intermediate and the hydrogenation of the formic acid intermediate into methanol. Low-energy spans (25.6, 22.1, and 20.6 kcal/mol) are achieved, indicating that CO can be hydrogenated into methanol at low temperatures. The new extended aromatization-dearomatization effect involving multiple rings is proposed to effectively facilitate the rate-determining CO 1,1-addition step, and a new CO activation model is proposed for organic catalysts.
RESUMO
A brand-new enhanced starvation is put forward to trigger sensitized chemotherapy: blocking tumor-relation blood vessel formation and accelerating nutrient degradation and efflux. Following this concept, two cisplatin-like gemfibrozil-derived Pt(IV) prodrugs, GP and GPG, are synthesized. GP and GPG had nanomolar IC50 against A2780 cells and higher selectivity against normal cells than cisplatin. Bioactivity results confirmed that GP and GPG highly accumulated in cells and induced DNA damage, G2-phase arrest, and p53 expression. Besides, they could increase ROS and MDA levels and reduce mitochondrial membrane potential and Bcl-2 expression to promote cell apoptosis. In vivo, GP showed superior antitumor activity in A2780 tumor-bearing mice with no observable tissue damage. Mechanistic studies suggested that highly selective chemotherapy could be due to the new enhanced starvation effect: blocking vasculature formation via inhibiting the CYP2C8/EETs pathway and VEGFR2, NF-κB, and COX-2 expression and cholesterol efflux and degradation acceleration via increasing ABCA1 and PPARα.
Assuntos
Antineoplásicos , Genfibrozila , Animais , Humanos , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Genfibrozila/farmacologia , Camundongos Endogâmicos BALB C , Compostos Organoplatínicos/farmacologia , Compostos Organoplatínicos/química , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Pró-Fármacos/síntese químicaRESUMO
Objective: Cognitive symptoms are associated with significant dysfunction in schizophrenia. Oxidative stress and inflammation involving histone deacetylase (HDAC) have been implicated in the pathophysiology of schizophrenia. Sulforaphane has antioxidant properties and is an HDAC inhibitor. The objective of this study was to determine the efficacy of sulforaphane on cognition dysfunction for patients with schizophrenia. Methods: This double-blind randomized 22-week trial of patients with first-episode schizophrenia was conducted in four psychiatric institutions in China. Patients were randomized to three groups (two doses of sulforaphane vs. placebo) and symptomatic and cognitive assessments were completed at multiple times. The primary outcome measure was change in the MATRICS Composite score. The secondary outcomes were change in MATRICS Domain scores, PANSS Total Scores and change in side-effects. Results: A total of 172 patients were randomized and 151 patients had at least one follow up evaluation. There were no significant effects of sulforaphane, on the primary outcome, MATRICS overall composite score. However, on secondary outcomes, sulforaphane did significantly improve performance scores on MATRICS battery Domains of spatial working memory (F = 5.68, P = 0.004), reasoning-problem solving (F = 2.82, P = 0.063), and verbal learning (F = 3.56, P = 0.031). There were no effects on PANSS symptom scores. Sulforaphane was well tolerated. Conclusion: Although the primary outcome was not significant, improvement in three domains of the MATRICS battery, suggests a positive cognitive effect on some cognitive functions, which warrants further clinical trials to further assess whether sulforaphane may be a useful adjunct for treating some types of cognitive deficits in schizophrenia.