ABSTRACT
Background and Objectives: Non-alcoholic fatty liver disease (NAFLD) is highly prevalent worldwide. It progresses from simple steatosis to non-alcoholic steatohepatitis (NASH). Fibrosis is often present during NAFLD progression; however, factors determining which subjects develop NASH or fibrosis are unclear. Insulin-like growth factor binding proteins (IGFBPs) are a family of secreted proteins involved in senescence and scarring, mainly synthetized in the liver. Here, we aimed to study the association of IGFBPs and their induced senescence with the progression of NAFLD and liver fibrosis. Materials and Methods: A total of 16-week-old male C57BL/6 mice weighing 23 ± 3 g were fed either methionine/choline-deficient (MCD) or control diet for 2, 8, or 12 weeks. Blood and liver samples were collected, and a histological assessment of NAFLD and fibrosis was performed. Fat contents were measured. Cellular senescence was evaluated in the liver. IGFBP levels were assessed in the liver and serum. Data were expressed as mean ± SD and analyzed by a one-way ANOVA followed by Tukey's test. Lineal regression models were applied for NAFLD and fibrosis progression. p < 0.05 was considered significant. Results: IGFBP-1 and -2 were increased in serum during NAFLD. IGFBP-7 was significantly increased in the serum in NASH compared with the controls. Senescence increased in NAFLD. Serum and liver IGFBP-7 as well as SA-ß-gal activity increased as fibrosis progressed. Both IGFBP-7 and cellular senescence were significantly higher during NAFLD and fibrosis in MCD-fed mice. Conclusions: IGFBP-1, -2, and -7, through their consequent senescence, have a role in the progression of NAFLD and its associated fibrosis, being a plausible determinant in the progression from steatosis to NASH.
Subject(s)
Non-alcoholic Fatty Liver Disease , Male , Humans , Mice , Animals , Non-alcoholic Fatty Liver Disease/complications , Insulin-Like Growth Factor Binding Protein 1 , Insulin-Like Peptides , Mice, Inbred C57BL , Liver , Liver Cirrhosis/complications , Choline/metabolism , Choline/pharmacology , Cellular Senescence , Disease Models, AnimalABSTRACT
This study was carried out to compare the impact of choline supplementation (available from two sources synthetic and natural) on various dosages in broilers. The mode of choline supplementation, via diet and additional sources, synthetic and natural, and the data of performance, carcass quality, blood parameters, and hepatic steatosis were compared. A total of 1050 day-old male Cobb 500 broiler chicks were randomly assigned to 10 treatments, using a completely randomized design model in a factorial scheme, with 6 replicates per treatment and 25 birds per replicate. Choline was supplemented using three sources: synthetic choline chloride 60% (CC), and two sources of natural choline A (NCA), and B (NCB). The Control treatment did not receive any choline supplementation. The diets were supplemented with low, intermediate and high doses of choline sources (400g/t, 800g/t, and 1200g/t of CC; 100g/t, 200g/t, and 300g/t of both NCA and NCB). Data analysis was performed using a factorial model to investigate the effects of choline supplementation (CC, NCA, NCB) and doses on the measured variables. Overall, the results indicated that the the performance of NCA was better than CC & NCB, specifically the dose of 100g/t of NCA outperformed MAR at 100g/t & CC at 400g/t, leading to a significant increase in body weight gain (85.66g & 168.84g respectively), and a noteworthy (9- & 12-point respectively) improvement in feed conversion ratio. Furthermore, NCA contributed to a reduction in steatosis when contrasted with various NCB & CC doses, likely due to the presence of curcumins and catechins in the natural choline source. These findings demonstrated that NCA supplementation yielded superior results compared to CC and NCB across both performance and liver health aspects in broilers aged 1 to 42 days. In conclusion, NCA can be used to replace the CC 60% without compromise on the zootechnical performance in broilers.
Subject(s)
Chickens , Diet , Animals , Male , Animal Feed/analysis , Choline/pharmacology , Diet/veterinary , Dietary Supplements , Weight GainABSTRACT
Rumen-protected choline (RPC) promotes benefits in milk production, immunity, and health in dairy cows by optimizing lipid metabolism during transition period management and early lactation. However, the RPC success in dairy cows depends on choline bioavailability, which is affected by the type of protection used in rumen-protected choline. Therefore, our objectives were to determine the effects of a novel RPC on dry matter intake (DMI), identify markers of metabolism and immunity, and evaluate lactation performance. Dry Holstein (n = 48) cows at 245 ± 3 d of gestation were blocked by parity and assigned to control or RPC treatment within each block. Cows enrolled in the RPC treatment received 15 g/d of CholiGEM (Kemin Industries, Cavriago RE, Italy) from 21 d prepartum and 30 g/d of CholiGEM from calving to 21 d postpartum. During the transition period, DMI was measured daily, and blood was sampled weekly for energy-related metabolites such as ß-hydroxybutyrate (BHB), glucose, and nonesterified fatty acids (NEFA), as well as immune function markers such as haptoglobin (Hp) and lipopolysaccharide-binding protein (LPB). Vaginal discharge samples were collected at the calving and 7 d postpartum and stored in microcentrifuge tubes at -80°C until 16S rRNA sequencing. The main responses of body condition score, body weight, DMI, milk yield, milk components, and immune function markers were analyzed using the GLIMMIX procedure of SAS with the effects of treatment, time, parity, and relevant covariates added to the models. The relative abundance of microbiome α-diversity was evaluated by 3 indexes (Chao1, Shannon, and Simpson) and ß-diversity by principal coordinate analysis and permutational multivariate ANOVA. We found no differences in DMI in the pre- and postpartum periods. Cows fed RPC increased the yields of energy- and 3.5% fat-corrected milk and fat yield in primiparous and multiparous cows, with an interaction between treatment and parity for these lactation variables. However, we found no differences in milk protein and lactose up to 150 DIM between treatments. Glucose, NEFA, and BHB had no differences between the treatments. However, RPC decreased BHB numerically (control = 1.07 ± 0.13 vs. RPC = 0.63 ± 0.13) in multiparous on the third week postpartum and tended to reduce the incidence of subclinical ketosis (12.7% vs. 4.2%). No effects for Hp and LPB were found in cows fed RPC. Chao1, Shannon, and Simpson indexes were lower at calving in the RPC treatment than in the Control. However, no differences were found 7 d later for Chao1, Shannon, and Simpson indexes. The vaginal discharge microbiome was altered in cows fed RPC at 7 d postpartum. Fusobacterium, a common pathogen associated with metritis, was reduced in cows fed RPC. Rumen-protected choline enhanced lactation performance and health and altered the vaginal discharge microbiome which is a potential proxy for uterine healthy in dairy cows. The current study's findings corroborate that RPC is a tool to support adaptation to lactation and shed light on opportunities for further research in reproductive health.
Subject(s)
Cattle Diseases , Vaginal Discharge , Pregnancy , Female , Cattle , Animals , Choline/pharmacology , Choline/metabolism , Diet/veterinary , Dietary Supplements/analysis , Fatty Acids, Nonesterified , Rumen/metabolism , RNA, Ribosomal, 16S/metabolism , Postpartum Period/metabolism , Lactation/physiology , Glucose/metabolism , Vaginal Discharge/veterinary , Cattle Diseases/metabolismABSTRACT
Nonalcoholic steatohepatitis (NASH) is a disease with a high incidence worldwide, but its diagnosis and treatment are poorly managed. In this study, NASH pathophysiology and DNA damage biomarkers were investigated in mice with NASH treated and untreated with melatonin (MLT). C57BL/6 mice were fed a methionine- and choline-deficient (MCD) diet for 4 weeks to develop NASH. Melatonin was administered at 20 mg/kg during the last 2 weeks. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were measured, and hepatic tissue was dissected for histological analysis, evaluation of lipoperoxidation, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), as well as nuclear factor-erythroid 2 (Nrf2), tumor necrosis factor alpha (TNF-α), inducible nitric oxide synthase (iNOS), and transforming growth factor beta (TGF-ß) expression by immunohistochemistry. DNA damage was evaluated using Comet assay, while a micronucleus test in bone marrow was performed to assess the genomic instability associated with the disease. Melatonin decreased AST and ALT, liver inflammatory processes, balloonization, and fibrosis in mice with NASH, decreasing TNF-α, iNOS, and TGF-ß, as well as oxidative stress, shown by reducing lipoperoxidation and intensifying Nrf2 expression. The SOD and GPx activities were increased, while CAT was decreased by treatment with MLT. Although the micronucleus frequency was not increased in mice with NASH, a protective effect on DNA was observed with MLT treatment in blood and liver tissues using Comet assay. As conclusions, MLT slows down the progression of NASH, reducing hepatic oxidative stress and inflammatory processes, inhibiting DNA damage via anti-inflammatory and antioxidant actions.
Subject(s)
Choline Deficiency , Melatonin , Non-alcoholic Fatty Liver Disease , Alanine Transaminase , Animals , Anti-Inflammatory Agents/pharmacology , Antioxidants/metabolism , Antioxidants/pharmacology , Antioxidants/therapeutic use , Aspartate Aminotransferases , Biomarkers/metabolism , Catalase/metabolism , Choline/analysis , Choline/metabolism , Choline/pharmacology , Choline Deficiency/complications , Choline Deficiency/metabolism , DNA Damage , Diet , Glutathione Peroxidase/metabolism , Inflammation/metabolism , Liver/metabolism , Melatonin/pharmacology , Melatonin/therapeutic use , Methionine/analysis , Methionine/genetics , Methionine/metabolism , Mice , Mice, Inbred C57BL , NF-E2-Related Factor 2/metabolism , Nitric Oxide Synthase Type II/metabolism , Non-alcoholic Fatty Liver Disease/drug therapy , Oxidative Stress , Superoxide Dismutase/metabolism , Transforming Growth Factor beta/metabolism , Tumor Necrosis Factor-alpha/metabolismABSTRACT
Several antidepressants inhibit nicotinic acetylcholine receptors (nAChRs) in a non-competitive and voltage-dependent fashion. Here, we asked whether antidepressants with a different structure and pharmacological profile modulate the rat α7 nAChR through a similar mechanism by interacting within the ion-channel. We applied electrophysiological (recording of the ion current elicited by choline, ICh, which activates α7 nAChRs from rat CA1 hippocampal interneurons) and in silico approaches (homology modeling of the rat α7 nAChR, molecular docking, molecular dynamics simulations, and binding free energy calculations). The antidepressants inhibited ICh with the order: norfluoxetine ~ mirtazapine ~ imipramine < bupropion ~ fluoxetine ~ venlafaxine ~ escitalopram. The constructed homology model of the rat α7 nAChR resulted in the extracellular vestibule and the channel pore is highly negatively charged, which facilitates the permeation of cations and the entrance of the protonated form of antidepressants. Molecular docking and molecular dynamics simulations were carried out within the ion-channel of the α7 nAChR, revealing that the antidepressants adopt poses along the receptor channel, with slightly different binding-free energy values. Furthermore, the inhibition of ICh and free energy values for each antidepressant-receptor complex were highly correlated. Thus, the α7 nAChR is negatively modulated by a variety of antidepressants interacting in the ion-channel.
Subject(s)
Antidepressive Agents/chemistry , Antidepressive Agents/pharmacology , Ion Channels/metabolism , alpha7 Nicotinic Acetylcholine Receptor/chemistry , alpha7 Nicotinic Acetylcholine Receptor/metabolism , Animals , Antidepressive Agents/classification , Choline/pharmacology , Interneurons/drug effects , Interneurons/metabolism , Ion Channel Gating/drug effects , Molecular Docking Simulation , Molecular Dynamics Simulation , Rats , Structural Homology, Protein , Structure-Activity Relationship , ThermodynamicsABSTRACT
Aim: A sodium alginate-based biohydrogel was prepared integrating choline oleate deep euthetic solvent as facilitator of transdermal delivery and a cocktail of lytic bacteriophages for Acinetobacter baumannii, aiming at treating soft-tissue infections by the aforementioned pathogen. Materials & methods: Two bacteriophages were isolated from a hospital sewage and a wastewater treatment plant sewage in Sorocaba (Brazil), and characterized via SDS-PAGE electrophoresis, transmission electron microscope and evaluation of lytic spectra of the bacteriophage cocktail. The biohydrogel was prepared and characterized by DSC, FTIR, XRD, DESEM, XRT and transdermal permeation of the bacteriophage cocktail. Results & conclusion: The physico-chemical characterization of the biohydrogel produce indicated adequate structural characteristics and ability to promote/facilitate transdermal delivery of bacteriophage particles, thus showing potential for biopharmaceutical applications.
Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteriophages/physiology , Choline/pharmacology , Oleic Acid/pharmacology , Virion , Acinetobacter baumannii/drug effects , Brazil , DNA Damage , Disk Diffusion Antimicrobial Tests , Humans , Hydrogels/pharmacology , Phage TherapyABSTRACT
New findings on neural regulation of immunity are allowing the design of novel pharmacological strategies to control inflammation and nociception. Herein, we report that choline, a 7-nicotinic acetylcholine receptor (α7nAChRs) agonist, prevents carrageenan-induced hyperalgesia without affecting inflammatory parameters (neutrophil migration or cytokine/chemokines production) or inducing sedation or even motor impairment. Choline also attenuates prostaglandin-E2 (PGE2)-induced hyperalgesia via α7nAChR activation and this antinociceptive effect was abrogated by administration of LNMMA (a nitric oxide synthase inhibitor), ODQ (an inhibitor of soluble guanylate cyclase; cGMP), andglibenclamide(an inhibitor of ATP-sensitive potassium channels). Furthermore, choline attenuates long-lasting Complete Freund's Adjuvant and incision-induced hyperalgesia suggesting its therapeutic potential to treat pain in rheumatoid arthritis or post-operative recovery, respectively. Our results suggest that choline modulates inflammatory hyperalgesia by activating the nitric oxide/cGMP/ATP-sensitive potassium channels without interfering in inflammatory events, and could be used in persistent pain conditions.
Subject(s)
Choline/pharmacology , Cyclic GMP/metabolism , Hyperalgesia/drug therapy , Inflammation/drug therapy , KATP Channels/metabolism , Nitric Oxide/metabolism , alpha7 Nicotinic Acetylcholine Receptor/agonists , Animals , Choline/therapeutic use , Dinoprostone/metabolism , Freund's Adjuvant , Male , Mice , Mice, Inbred BALB CABSTRACT
Multiparous Holstein cows were assigned in a randomized complete block design into four treatments from 21 d before calving to 30 d in milk (DIM). Treatments were: MET [n = 19, fed the basal diet + rumen-protected methionine at a rate of 0.08% (w/w) of the dry matter, Smartamine® M], CHO (n = 17, fed the basal diet + choline 60 g/d, Reashure®), MIX (n = 21, fed the basal diet + Smartamine® M at a rate of 0.08% (w/w) of the dry matter and 60 g/d Reashure®), and CON (n = 20, no supplementation, fed the close-up and fresh cow diets). Follicular development was monitored via ultrasound every 2 d starting at 7 DIM until ovulation (n = 37) or aspiration (n = 40) of the first postpartum dominant follicle (DF). Follicular fluid from 40 cows was aspirated and cells were retrieved immediately by centrifugation. Gene expression of TLR4, TNF, IL1-ß, IL8, IL6, LHCGR, STAR, 3ß-HSD, P450scc, CYP19A1, IRS1, IGF, MAT1A, and SAHH, was measured in the follicular cells of the first DF. Cows in CON had higher TNF, TLR4, and IL1-ß mRNA expression (11.70 ± 4.6, 21.29 ± 10.4, 6.28 ± 1.4, respectively) than CHO (2.77 ± 0.9, 2.16 ± 0.9, 2.29 ± 0.7, respectively), and MIX (2.23 ± 0.7, 1.46 ± 0.6, 2.92 ± 0.8, respectively). Cows in CON had higher IL1-ß expression (6.27 ± 1.4) than cows in MET (3.28 ± 0.6). Expression of IL8 mRNA was lower for cows in CHO (0.98 ± 0.3) than cows in CON (4.90 ± 0.7), MET (6.10 ± 1.7), or MIX (5.05 ± 1.8). Treatments did not affect mRNA expression of LHCGR, STAR, P450scc, CYP19A, SAHH, MAT1A, or IL6 however, 3ß-HSD expression was higher for cows in MET (1.46 ± 0.3) and MIX (1.25 ± 0.3) than CON (0.17 ± 0.04) and CHO (0.26 ± 0.1). Supplementation of methionine, choline, and both methionine and choline during the transition period did not affect days to first ovulation or number of cows that ovulated the first follicular wave. Plasma and follicular fluid estradiol and progesterone concentrations were not different among treatments. Methionine concentrations in the follicular fluid of the first postpartum DF was higher for cows in MET (18.2 ± 0.1 µM) than cows in CON (11.1 ± 0.9 µM). In conclusion, supplementing choline and methionine during the transition period changed mRNA expression in follicular cells and dietary methionine supplementation increased plasma and follicular fluid concentrations of methionine of the first postpartum DF in Holstein cows.
Subject(s)
Cattle/physiology , Choline/pharmacology , Gene Expression Regulation/drug effects , Methionine/pharmacology , Ovarian Follicle/drug effects , Animals , Cattle/blood , Cattle/immunology , Choline/administration & dosage , Choline/chemistry , Dosage Forms , Estradiol/blood , Female , Gene Expression Regulation/immunology , Methionine/administration & dosage , Methionine/chemistry , Milk , Postpartum Period , PregnancyABSTRACT
New N-allyl/propargyl 4-substituted 1,2,3,4-tetrahydroquinolines derivatives were efficiently synthesized using acid-catalyzed three components cationic imino Diels-Alder reaction (70-95%). All compounds were tested in vitro as dual acetylcholinesterase and butyryl-cholinesterase inhibitors and their potential binding modes, and affinity, were predicted by molecular docking and binding free energy calculations (∆G) respectively. The compound 4af (IC50 = 72 µm) presented the most effective inhibition against acetylcholinesterase despite its poor selectivity (SI = 2), while the best inhibitory activity on butyryl-cholinesterase was exhibited by compound 4ae (IC50 = 25.58 µm) with considerable selectivity (SI = 0.15). Molecular docking studies indicated that the most active compounds fit in the reported acetylcholinesterase and butyryl-cholinesterase active sites. Moreover, our computational data indicated a high correlation between the calculated ∆G and the experimental activity values in both targets.
Subject(s)
Alkynes/chemical synthesis , Choline/analogs & derivatives , Computer Simulation , Quinolines/chemical synthesis , Alkynes/chemistry , Alkynes/pharmacology , Binding Sites , Cations , Choline/chemical synthesis , Choline/chemistry , Choline/pharmacology , Cholinesterase Inhibitors/chemical synthesis , Cholinesterase Inhibitors/chemistry , Cholinesterase Inhibitors/pharmacology , Cycloaddition Reaction , Enzyme Activation/drug effects , Humans , Kinetics , Quinolines/chemistry , Quinolines/pharmacologyABSTRACT
Nicotinic acetylcholine receptors (nAChRs) are widely distributed in the brain. Particularly α7-containing nAChRs, associated with several physiological roles and pathologies, are one of the most abundant. Here, we studied 2-(4-hexyloxybenzyl)-1-methylquinuclidin-1-ium iodide (designated as 8d), on ion currents elicited by choline, ICh, (Ch, a selective agonist for α7-containing nAChRs), recorded in interneurons from the stratum radiatum of the rat hippocampal CA1 region by using the whole-cell voltage-clamp technique. The 8d-concentration/Ch-response relationship exhibited high and low inhibitory affinities for α7-containing nAChRs, with IC50 values of 0.59 and 6.80 µM, respectively. Interestingly, 8d in a range of 3-10 µM exerted opposite effects: a short early potentiation and a long late inhibition of the ICh; and 8d alone elicited a non-decaying inward current. Furthermore, potentiation and inhibition of the ICh by 8d depended on the membrane potential, both being stronger at -20 than at -70 mV; indicating that 8d interacts with at least two sites into the ion channel/receptor complex: one for potentiating and another for inhibiting the α7-containing nAChRs. These results suggest that 8d may act as agonist, antagonist and positive modulator of α7-containing nAChRs in hippocampal interneurons.
Subject(s)
CA1 Region, Hippocampal/metabolism , Interneurons/metabolism , Quinuclidines/pharmacology , alpha7 Nicotinic Acetylcholine Receptor/metabolism , Animals , CA1 Region, Hippocampal/cytology , Choline/pharmacology , In Vitro Techniques , Rats, Sprague-Dawley , alpha7 Nicotinic Acetylcholine Receptor/agonists , alpha7 Nicotinic Acetylcholine Receptor/antagonists & inhibitorsABSTRACT
The incidence of facial trauma is high. This study has the primary objective of documenting and cataloging maxillofacial fractures in polytrauma patients. From a total of 1229 multiple trauma cases treated at the Emergency Room of the Santo Antonio Hospital - Oporto Hospital Center, Portugal, between August 2001 and December 2007, 251 patients had facial wounds and 209 had maxillofacial fractures. Aged ranged form 13 to 86 years. The applied selective method was based on the presence of facial wound with Abbreviated Injury Scale ≥1. Men had a higher incidence of maxillofacial fractures among multiple trauma patients (86.6%) and road traffic accidents were the primary cause of injuries (69.38%). Nasoorbitoethmoid complex was the most affected region (67.46%) followed by the maxilla (57.42%). The pattern and presentation of maxillofacial fractures had been studied in many parts of the world with varying results. Severe multiple trauma patients had different patterns of maxillofacial injuries. The number of maxillofacial trauma is on the rise worldwide as well as the incidence of associated sequelae. Maxillofacial fractures on multiple trauma patients were more frequent among males and in road traffic crashes. Knowing such data is elementary. The society should have a key role in the awareness of individuals and in prevention of road traffic accidents.
É alta a incidência de traumas na face. Este estudo teve por objetivo documentar e catalogar as fraturas maxilofaciais em pacientes com politraumatismos. De um total de 1229 casos de politraumatizados tratados na Sala de Emergência do Hospital de Santo António - Centro Hospitalar do Porto, Portugal, entre Agosto de 2001 e Dezembro de 2007, 251 pacientes tiveram ferimentos na face e 209 apresentaram fraturas maxilofaciais. As idades variaram de 13 a 86 anos. O método de seleção baseou-se na presença de ferimentos na face com Abreviated Injury Scale ≥1. Os homens apresentaram maior incidência de fraturas maxilofaciais (86,6%) entre os pacientes com múltiplos traumatismos na face e os acidentes de trânsito foram a causa principal dos traumatismos (69,38%). A região mais afetada foi o complexo naso-órbito-etmoidal (67,46%), seguido pela maxila (57,42%). O padrão e a apresentação das fraturas maxilofaciais tem sido estudado em muitas regiões do mundo com resultados variados. Pacientes com politraumatizados graves apresentaram padrões diferentes de traumatismos maxilofaciais. O número de traumatismos maxilofaciais tem aumentado à escala mundial, assim como a incidência das sequelas associadas. Entre os pacientes com traumatismos múltiplos, a maioria pertencia ao sexo masculino, assim como a causa mais frequente foram os acidentes automobilísticos. É elementar o conhecimento destes dados. A sociedade tem um papel primordial nos cuidados individuais e na prevenção dos acidentes de trânsito.
Subject(s)
Animals , Male , Mice , Rats , Cholinesterase Reactivators , Choline/analogs & derivatives , Diazinon/antagonists & inhibitors , Neurotransmitter Agents/pharmacology , Physostigmine/antagonists & inhibitors , Pyrrolidines/antagonists & inhibitors , Choline/metabolism , Choline/pharmacology , Cholinesterase Inhibitors/toxicity , Diazinon/toxicity , Mice, Inbred ICR , Physostigmine/toxicity , Pyrrolidines/toxicity , Rats, Inbred Strains , Receptors, Cholinergic/drug effects , Receptors, Cholinergic/metabolismABSTRACT
It is widely known that pre-training systemic administration of the muscarinic antagonist scopolamine (SCP) (0.5mg/kg, i.p.) leads to anterograde memory impairment in retention tests. The administration of the α(7)-nicotinic receptor agonist choline (Ch) in the dorsal hippocampus (0.8µg/hippocampus) immediately after memory reactivation allowed recovery from scopolamine-induced memory impairment. This effect of Ch was time-dependent, and retention performance was not affected in drug-treated mice that were not subjected to memory reactivation, suggesting that the performance effects are not due to non-specific effects of the drug. The effects of Ch also depended on the age of the reactivated memory. Altogether, our results suggest that Ch exerts its effects by modulating memory reconsolidation, and that the memory impairment induced by low doses of SCP is a memory expression failure and not a storage deficit. Therefore, reconsolidation, among other functions, might serve to change memory expression in later tests. Summarizing, our results open new avenues about the behavioral significance and the physiological functions of memory reconsolidation, providing new strategies for recovering memories from some types of amnesia.
Subject(s)
Choline/pharmacology , Hippocampus/drug effects , Memory/drug effects , Nicotinic Agonists/pharmacology , Nootropic Agents/pharmacology , Animals , Avoidance Learning/drug effects , Hippocampus/physiology , Male , Memory Disorders/chemically induced , Mice , Muscarinic Antagonists/pharmacology , Retention, Psychology/drug effects , Scopolamine/pharmacology , Time FactorsABSTRACT
La actividad del transportador de colina de alta afinidad (HAChT) es considerado el paso limitante en la síntesis de acetilcolina (ACh) en el terminal colinérgico. Estudios recientes muestran que el HAChT contiene residuos de serina y treonina consensuales para la fosforilación por proteína kinasa A (PKA). Usando neuronas de retina de embrión de pollo se evaluó el efecto del segundo mensajero AMPc sobre la actividad del HAChT. El aumento de los niveles intracelulares de AMPc a través de la inhibición de la fosfodiesterasa, activación de la adenilato ciclasa o usando un análogo de AMPc resistente a la fosfodiesterasa disminuyó la actividad del HAChT entre 29 y 69%. Por otra parte, la activación de receptores de dopamina tipo-D1 aumenta los niveles de AMPc intracelular y activa PKA, sin embargo, el tratamiento con dopamina o con antagonistas de los receptores dopaminergicos D1 o D2 no induce cambios en la actividad del transportador
The high affinity choline transporter (HAChT) activity is considered to be the rate-limiting step in acetylcholine (ACh) synthesis in the cholinergic terminal. Recent studies show that HAChT contains consensus serine and threonine residues for protein kinase A (PKA) phosphorylation. Using chick retinal neurons evaluated the effects of the second messenger cAMP on the HAChT activity. The increase of the intracellular cAMP levels through phosphodiesterase inhibition, adenilatecyclase activation or using a phosphodiesterase-resistant cAMP analog decreased HAChT activity between 29 and 69%. Moreover, the activation of dopamine D1-type receptors increase the intracellular cAMP levels and activates PKA, however, the treatment with dopamine D1 or D2 receptor antagonists does not induce changes on transporter activity
Subject(s)
Chick Embryo , Central Nervous System , Choline/pharmacology , Alzheimer Disease/ethnology , Parkinson Disease/etiology , Pharmacology, ClinicalABSTRACT
CF-1 male mice were trained in an inhibitory avoidance (IA) task using either a mild or a high footshock (0.8 or 1.2 mA, 50 Hz, 1 s). A retention test was given 48 h later. Immediately after the retention test, mice were given intra-dorsal hippocampus infusions of either choline (Ch, an α7 nicotinic acetylcholine receptor (α7nAChR) agonist, 0.08-1.30 µg/hippocampus), or methyllycaconitine (MLA, an α7nAChR antagonist, 1.0-30.0 µg/hippocampus). Memory retention was tested again 24 h later. Methyllycaconitine impaired retention performance regardless of footshock intensity and its effects were long lasting. Ch impaired retention performance only in those mice trained with a high footshock. On the contrary, Ch enhanced retention performance when mice were trained with a mild footshock. These effects were long lasting and dose- and time-dependent. Retention performance was not affected in drug-treated mice that were not subjected to memory reactivation, suggesting that the performance effects could not be attributable to non-specific effects of the drugs. Methyllycaconitine effects were dose-dependently reversed by choline, suggesting that MLA and Ch interact at the α7nAChR. Altogether, results suggest that hippocampal α7nAChRs play a critical role in reconsolidation of an IA response in mice, and may also have important implications for dynamic memory processes. This is the first presentation, to our knowledge, indicating that a specific receptor (α7nAChR) is able to modulate consolidated memories after retrieval.
Subject(s)
Avoidance Learning/drug effects , Hippocampus/drug effects , Memory/drug effects , Receptors, Nicotinic/physiology , Aconitine/analogs & derivatives , Aconitine/pharmacology , Animals , Choline/pharmacology , Hippocampus/metabolism , Inhibition, Psychological , Male , Mice , Nicotinic Agonists/pharmacology , Nicotinic Antagonists/pharmacology , alpha7 Nicotinic Acetylcholine ReceptorABSTRACT
Since the establishment of the 1998 folate recommended dietary allowance (RDA), the methylenetetrahydrofolate reductase (MTHFR) 677C-->T variant has emerged as a strong modifier of folate status. This controlled feeding study investigated the adequacy of the RDA, 400 microg/d as dietary folate equivalents (DFE), for Mexican American men with the MTHFR 677CC or TT genotype. Because of the interdependency between folate and choline, the influence of choline intake on folate status was also assessed. Mexican American men (n = 60; 18-55 y) with the MTHFR 677CC (n = 31) or TT (n = 29) genotype consumed 438 microg DFE/d and total choline intakes of 300, 550 (choline adequate intake), 1100, or 2200 mg/d for 12 wk. Folate status response was assessed via serum folate (SF), RBC folate, plasma total homocysteine (tHcy), and urinary folate. SF decreased (P < 0.001) 66% to 7.9 +/- 0.7 nmol/L (means +/- SEM) in men with the 677TT genotype and 62% to 11.3 +/- 0.9 nmol/L in the 677CC genotype. Plasma tHcy increased (P < 0.0001) 170% to 31 +/- 3 micromol/L in men with the 677TT genotype and 18% to 11.6 +/- 0.3 micromol/L in the 677CC genotype. At the end of the study, 34% (677TT) and 16% (677CC) had SF concentrations <6.8 nmol/L and 79% (677TT) and 7% (677CC) had tHcy concentrations >14 micromol/L. Choline intake did not influence the response of the measured variables. These data showed that the folate RDA is not adequate for men of Mexican descent, particularly for those with the MTHFR 677TT genotype, and demonstrated a lack of influence of choline intake on the folate status variables measured in this study.
Subject(s)
Folic Acid Deficiency/metabolism , Folic Acid/administration & dosage , Folic Acid/pharmacology , Methylenetetrahydrofolate Reductase (NADPH2)/genetics , Mexican Americans/genetics , Nutrition Policy , Adult , Choline/pharmacology , Diet , Dose-Response Relationship, Drug , Genetic Variation , Genotype , Humans , Male , Middle Aged , Vitamin B Complex/administration & dosage , Vitamin B Complex/pharmacologyABSTRACT
Pseudomonas aeruginosa expresses hemolytic phospholipase C (PlcH) with choline or under phosphate-limiting conditions. PlcH from these conditions were differently eluted from the Celite-545 column after application of an ammonium sulfate linear reverse gradient. The PlcH from supernatants of bacteria grown in the presence of choline was eluted with 30% ammonium sulfate and was more than 85% inhibited by tetradecyltrimethylammonium. PlcH from supernatants of bacteria grown with succinate and ammonium ions in a low-phosphate medium was eluted as a peak with 10% of salt and was less than 10% inhibited by tetradecyltrimethylammonium. PlcH from low phosphate was purified associated with a protein of 17 kDa. This complex was dissociated and separated on a Sephacryl S-200 column with 1% (w/v) sodium dodecyl sulfate. After this dissociation, the resulting protein of 70 kDa, corresponding to PlcH, was inhibited by tetradecyltrimethylammonium, showing a protection effect of the accompanying protein. RT-PCR analyses showed that in choline media, the plcH gene was expressed independently of plcR. In low-phosphate medium, the plcH gene was expressed as a plcHR operon. Because plcR encodes for chaperone proteins, this result correlates with the observation that PlcH from supernatants of bacteria grown in the presence of choline was purified without an accompanying protein. The consequence of the absence of this chaperone was that tetradecyltrimethylammonium inhibited the PlcH activity.
Subject(s)
Choline/pharmacology , Pseudomonas aeruginosa/enzymology , Surface-Active Agents/pharmacology , Trimethyl Ammonium Compounds/pharmacology , Type C Phospholipases/antagonists & inhibitors , Bacterial Proteins , Culture Media , Enzyme Induction , Gene Expression Regulation, Bacterial , Hemolysis , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/genetics , Pseudomonas aeruginosa/growth & development , Type C Phospholipases/genetics , Type C Phospholipases/metabolismABSTRACT
Choline is important for the synthesis of acetylcholine, an integral neurotransmitter involved in memory formation. In order to investigate the effect of choline supplementation on memory consolidation, the study utilized a T-maze to facilitate passive avoidance learning and memory in young female Sprague-Dawley rats. Rats were placed in two groups; choline-supplemented that received choline chloride daily for two weeks, and control that received vehicle daily for two weeks. Rats were evaluated to determine their ability to avoid an aversive electric foot-shock (0.1 mA at 60V) when they characteristically entered the preferred dark area (DA) of the T-maze. Both groups of rats showed preference, without significant difference, for entry into DA of the T-maze. However, fifteen minutes after passive avoidance both choline supplemented and control rats avoided entry into DA. This display of DA avoidance 15 minutes after training, suggests that both groups of rats had acquired short-term memory of the aversive stimulus. However, when the test was repeated 24 hours after training, the control group did not avoid entry into DA, whereas the choline-supplemented group either avoided entry or entered after a significantly longer latency period (p < 0.01). These results suggest that supplementation with choline facilitated the consolidation of short-term memory of the avoidance learning into intermediate long-term memory in young rats.
Subject(s)
Avoidance Learning/drug effects , Choline/pharmacology , Dietary Supplements , Memory, Short-Term/drug effects , Age Factors , Animals , Female , Memory/drug effects , Rats , Rats, Sprague-Dawley , Time FactorsABSTRACT
Choline is important for the synthesis of acetylcholine, an integral neurotransmitter involved in memory formation. In order to investigate the effect of choline supplementation on memory consolidation, the study utilized a T-maze to facilitate passive avoidance learning and memory in young female Sprague-Dawley rats. Rats were placed in two groups; choline-supplemented that received choline chloride daily for two weeks, and control that received vehicle daily for two weeks. Rats were evaluated to determine their ability to avoid an aversive electric foot-shock (0.1 mA at 60V) when they characteristically entered the preferred dark area (DA) of the T-maze. Both groups of rats showed preference, without significant difference, for entry into DA of the T-maze. However, fifteen minutes after passive avoidance both choline supplemented and control rats avoided entry into DA. This display of DA avoidance 15 minutes after training, suggests that both groups of rats had acquired short-term memory of the aversive stimulus. However, when the test was repeated 24 hours after training, the control group did not avoid entry into DA, whereas the choline-supplemented group either avoided entry or entered after a significantly longer latency period (p < 0.01). These results suggest that supplementation with choline facilitated the consolidation of short-term memory of the avoidance learning into intermediate long-term memory in young rats.
La colina es importante para la síntesis de la acetilcolina un neurotransmisor integral que participa en la formación de la memoria. Para investigar el efecto de la suplementación con colina en la consolidación de la memoria, el estudio utilizó un laberinto T para facilitar la memoria y el aprendizaje de evitación pasiva en ratas hembras jóvenes Sprague-Dawley. Las ratas fueron colocadas en dos grupos: uno que recibió cloruro de colina diariamente por espacio de dos semanas, y uno de control que recibió vehículo diariamente por dos semanas. Las ratas fueron evaluadas a fin de determinar su habilidad para evitar un choque eléctrico aversivo (0.1mA a 60V) cuando entraban característicamente a la preferida área oscura (AO) del laberinto en T. Ambos grupos de ratas mostraron preferencia sin diferencia significativa por entrar en el área oscura del laberinto en T. Sin embargo, quince minutos después de la evitación pasiva, tanto las ratas que recibieron la suplementación con colina como las ratas de control, evitaban entrar al área oscura. El hecho de que se observe la evitación del área oscura15 minutos después del entrenamiento, sugiere que ambos grupos de ratas habían adquirido una memoria a corto plazo del estímulo aversivo. Sin embargo, cuando la prueba se repitió 24 horas después del entrenamiento, el grupo de control no evitó el entrar al AO, mientras que el grupo que recibió el complemento de colina, o evitó entrar o entró luego de un período de latencia significativamente más largo (P < 0.01). Por lo tanto, estos resultados sugieren por consiguiente que la suplementación con colina facilitó la consolidación de la memoria a corto plazo del aprendizaje de la evitación, y su transformación en memoria a largo plazo en las ratas jóvenes.
Subject(s)
Animals , Female , Rats , Avoidance Learning/drug effects , Choline/pharmacology , Memory, Short-Term/drug effects , Dietary Supplements , Age Factors , Time Factors , Memory/drug effects , Rats, Sprague-DawleyABSTRACT
In this study, we investigated the effect of aging on intracellular Ca2+ stores, as sarcoendoplasmic reticulum (SR) and mitochondria, and the influence of these compartments on contraction of rat colon smooth muscle [Bitar, K.N., 2003. Aging and neural control of the GI tract V. Aging and gastrointestinal smooth muscle: from signal transduction to contractile proteins. Am. J. Physiol. Gastrointest. Liver. Physiol. 284(1), G1-G7; Marijic, J., Li, Q.X., Song, M., Nishimaru, K., Stefani, E., Toro, L., 2001. Decreased expression of voltage-and Ca2+-activated K+ channels in coronary smooth muscle during aging. Circ. Res. 88, 210-234; Rubio, C., Moreno, A., Briones, A. Ivorra, M.D., D'Ocon, P., Vila, E., 2002. Alterations by age of calcium handling in rat resistance arteries. J. Cardiovasc. Pharmacol. 40(6), 832-840]. Calcium stores and contraction were evaluated by simultaneous measurements of fluorescence and tension in smooth muscle strips loaded with fura-2. Results showed that activation of muscarinic receptors by methylcholine (MCh, 10 microM), induced a greater contraction in aged rats than in adult animals. The inhibition of Ca2+ ATPase by thapsigargin (TG, 1 microM) did not prevent the refilling of SR either in adult or aged rats. MCh, in the presence of TG, induced an increase in transient fluorescence, indicating a release of Ca2+ from TG-insensitive compartment. The mitochondrial uncoupler, FCCP (5 microM), caused a greater increase in intracellular Ca2+ and tension in aged rats, indicating that mitochondria may accumulate more Ca2+ during aging. The present results show that changes in intracellular Ca2+ stores, such as mitochondria and SR, affect contraction and may cause dysfunctions during aging that could culminate in severe alterations of Ca2+ homeostasis and cell damage.
Subject(s)
Aging/metabolism , Calcium/metabolism , Colon/metabolism , Muscle Contraction/physiology , Muscle, Smooth/metabolism , Aging/physiology , Animals , Calcium-Transporting ATPases/antagonists & inhibitors , Calcium-Transporting ATPases/physiology , Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone/pharmacology , Choline/analogs & derivatives , Choline/pharmacology , Colon/drug effects , Colon/physiology , Drug Interactions , Enzyme Inhibitors/pharmacology , Female , Mitochondria, Muscle/metabolism , Muscle Contraction/drug effects , Muscle, Smooth/drug effects , Muscle, Smooth/physiology , Rats , Rats, Wistar , Sarcoplasmic Reticulum/metabolism , Thapsigargin/pharmacology , Tissue Culture Techniques , Uncoupling Agents/pharmacologyABSTRACT
Fetal nutrition sets the stage for organ function in later life. In this review we discuss the fetal and neonatal origins of brain function. Numerous research observations point to the importance of choline for the developing fetus and neonate. This essential nutrient is involved in 1-carbon metabolism and is the precursor for many important compounds, including phospholipids, acetylcholine, and the methyl donor betaine. Dietary intake of choline by the pregnant mother and later by the infant directly affects brain development and results in permanent changes in brain function. In rodents, perinatal supplementation of choline enhances memory and learning functions, changes that endure across the lifespan. Conversely, choline deficiency during these sensitive periods results in memory and cognitive deficits that also persist. Furthermore, recent studies suggest that perinatal choline supplementation can reduce the behavioral effects of prenatal stress and the cognitive effects of prenatal alcohol exposure in offspring. The likely mechanism for these effects of choline involves DNA methylation, altered gene expression, and associated changes in stem cell proliferation and differentiation. The currently available animal data on choline and hippocampal development are compelling, but studies are needed to determine whether the same is true in humans.