D-chiro-inositol prevents memory deficits in the 3xTg mouse model of Alzheimer’s disease in a sex-dependent manner.

Subida por la tutora, a petición de Beatriz Pacheco Sánchez.Alzheimer’s disease (AD) is recognized as an age-related neurodegenerative disorder, characterized by the aggregation and deposition of amyloid-β (Aβ) in plaques and neurofibrillary tangles (NFTs) composed of aggregates of hyperphosphorylated tau, a microtubule-associated protein. Sporadic AD, the most prevalent form of the disease, has been proposed to be associated with alterations on insulin signaling. Insulin regulates a series of cognitive processes, such as learning and memory formation and emerging data demonstrate pivotal roles for brain insulin resistance and insulin deficiency as mediators of neurodegeneration, particularly in AD. The present study describes the effect of oral dietary administration of D-Chiro-inositol (DCI), an inositol used against insulin resistance, on the occurrence of the cognitive impairment of 3xTg-AD mice. This so called “triple‐ transgenic mice” model mimics many critical aspects of AD neuropathology. To this end, we analysed the effects of daily oral administration DCI 200 mg/Kg/day in male and female 3xTg and WT mice of 9 and 3 months of age. In addition to the evaluation of memory on the Novel Object Recognition, both the locomotion and time in the centre zone of an open field (OF), and the locomotion and anxiety-like behaviour in the elevated plus maze (EPM) test, were monitored. Our results showed that the exploration time of the new object was remarkably higher in the male 3xTg-DCI group when compared to those obtained from the 3xTg-vehicle and WT- vehicle groups at a middle and older age (3 and 9 months). When the center exploration time was analyzed in OPF test, three-way ANOVA showed an effect of the genotype in middle-aged animals. In the EPM test, only 9 months old 3xtg-DCI females were more prone to explore the open-arm, suggesting DCI decreases anxiety levels related to AD. In conclusion, our study suggest that DCI prevents and improves in a sex-dependent manner, the cognitive impairment associated to AD.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Reduction of adult hippocampal neurogenesis modifies brain functional connectivity and enhances cocaine-seeking in mice

Recently, adult hippocampal neurogenesis has been proposed as a putative neuroplastic mechanism involved in those behavioural processes. In this work, we studied the effect of the inhibition of adult hippocampal neurogenesis using the DNA alkylating agent temozolomide (TMZ), in cocaine-induced conditioned place preference (CPP) behaviour. In a first experiment, we investigated both CPP acquisition/expression and the functional brain circuits underlying CPP expression in control and neurogenesis-reduced conditions by analysing c-Fos immunoreactivity (c-Fos IR) in hippocampal and extrahippocampal addiction-related areas. A second experiment was designed to study the involvement of adult-born neurons in the extinction and cocaine-induced reinstatement of drug-seeking in the CPP model. We performed two independent studies where adult hippocampal neurogenesis was inhibited either before or after the CPP was acquired. Our results showed that TMZ treatment had no effect on the acquisition of the cocaine-induced CPP, but c-Fos IR associated to the test trial (CPP expression) revealed an increased activity in some of the analysed brain areas in the CPP-TMZ mice. Correlational and multivariate analysis revealed that, under normal conditions, the hippocampus showed widespread functional connectivity with other brain areas and strongly contributed to the functional brain network associated with CPP expression. However, mice with reduced neurogenesis showed an alternative brain circuit. The results of the second experiment revealed that mice acquiring the cocaine-induced CPP under neurogenesis-reduced conditions were delayed in extinguishing their drug seeking behaviour. However, when neurogenesis was inhibited after CPP acquisition, extinction was not affected but an enhanced long-term CPP retention was found, suggesting that the role of the adult-born neurons may differ depending on whether they are generated before or after drug-contextual associations are established. Importantly, cocaine-induced reinstatement of CPP behaviour was increased in the TMZ mice, regardless of the time of neurogenesis inhibition.Universidad de Málaga. Andalucía Tech, Campus de Excelencia Internacional. Spanish Ministry of Economy and Competitiveness (PSI2013-44901-P to L.J.S.; Subprograma RETICS Red de Trastornos Adictivos RD12/0028/0001, to F.R.F.). Author E.C-O. holds a ‘Sara Borrell’ research contract from the Spanish Carlos III Health Institute, Spanish Ministry of Economy and Competitiviness (grant number CD12/00455). Author D.L.G-M. holds a ‘FPU’ grant from the Spanish Ministry of Education, Culture and Sports (grant number FPU13/04819)

Persistent changes in exploration and hyperactivity coexist with cognitive impairment in mice withdrawn from chronic cocaine

Repeated cocaine exposure induces lasting neurobehavioral adaptations such as cognitive decline in animal models. However, persistent changes in spontaneous –unconditioned- motor and exploratory responses are scarcely reported. In this study, mice were administered with cocaine (20 mg/kg/day) or vehicle for 12 consecutive days. After 24 days of drug abstinence, a behavioral assessment was carried out in drug-free conditions and in unfamiliar environments (i.e. no cocaine-associated cues were presented). The cocaine-withdrawn mice showed cognitive deficits in spontaneous alternation behavior and place recognition memory. Importantly, they also displayed hyperlocomotion, increased rearing activity and altered exploratory patterns in different tasks. In the forced swimming test, they were more active (struggled/climbed more) when trying to escape from the water albeit showing normal immobility behavior. In conclusion, in addition to cognitive deficits, chronic cocaine in rodents may induce long-lasting alterations in exploratory activity and psychomotor activation that are triggered even in absence of drug-related stimuli.This study was funded by grants from the Spanish Ministry of Economy and Competitiveness (MINECO, Agencia Estatal de Investigación –AEI-) cofounded by the European Regional Development Fund-FEDER, UE- (PSI2015–73,156-JIN to E.C–O.; PSI2017–82604R to L.J.S.), RETICS Red de Trastornos Adictivos (ERDF-EU; RD16/0017/0001 to F.R.F.) and University of Málaga (B4: ‘Ayudas para Proyectos Puente’to E.C–O). Funding for open access charge: Universidad de Málaga /CBUA. Authors M.C.M-P., F. A-G. and S. G-R. hold predoctoral grants from the Spanish Ministry of Science, Innovation and Universities (FPU17/00276 to M.C.M-P.; PRE2018–085673 to F.A-G.; and FPU18/00941 to S.G-R.). Author D.L.G.M. holds a postdoctoral grant from University of Málaga (A.3. Plan Propio de Investigación y Transferencia Universidad de Málaga)

LH-21, a CB1 antagonist, reduces hepatotoxic damage produced by paracetamol overdose in a mice model.

Drug-induced liver injury (DILI) is one of the main causes of hepatic acute failure. Paracetamol can cause it when is ingested in excessive doses, leading to the depletion of the antioxidant mechanisms of the hepatocytes and a series of processes that conclude with cell death. One of the altered metabolic pathways is the endocannabinoid system (ECS), which has become a very interesting target to alleviate these events due to its involvement in inflammatory processes. For this reason, the triazole-derived compound LH-21, a cannabinoid receptor Cb1 antagonist, was used for the treatment of DILI in 8-week-old male C57BL/6 mice. In the present study, fasting mice were subjected to an oral overdose of paracetamol (300 mg/kg) and treated 2 hours later with 3 mg/kg of LH-21. After 24 hours, the animals were sacrificed and the livers were collected to determine the hepatic levels of metabolites related to antioxidant mechanisms, the expression of proteins involved in the generation of cellular damage and the transcription grade of the different components of the ECS. The observed results showed that LH-21 treatment raises GSH levels and total antioxidant capacity, in addition to reducing malondialdehyde values. Furthermore, the phosphorylation degree of Jnk and Stat3, as well as the activation status of Casp3, diminished. Regarding the ECS, the expression of Ppara, Cnr1, Cnr2 and Gpr55 did return to normal levels. This suggests that LH-21 effectively blocks the Cb1 activity, allowing the correct function of Ppar-α that promotes a cellular anti-inflammatory state and the relief of the symptoms produced by DILI. These results exhibit a promising perspective for the prevention or treatment of some toxic effects of paracetamol overdose with LH-21. Nevertheless, these findings are a first step to continue studying the involvement of the ECS in this type of liver disease and investigating the effectiveness of this Cb1 antagonist against the pathophysiology of DILI.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Persistent drug-associated memories coexist with hippocampal-dependent cognitive decline and altered adult hippocampal neurogenesis in mice withdrawn from cocaine.

Aims: Using a new animal model (‘chronic’ cocaine-induced conditioned place preference –CPP- paradigm), this work studied whether the long-term maintenance of cocaine-associated memories was concomitant to cognitive impairment and adult hippocampal neurogenesis (AHN) alterations. Methods: Male c57BL/6J mice were submitted to a CPP task treated either with cocaine (20 mg/kg/day) or saline for 14 days (n=10 per group). Bromodeoxyuridine (BrdU) was administered to label the new hippocampal neurons generated one week after the last cocaine dose. After 28 drug-free days, mice were assessed for the CPP memory and on a battery of emotional and cognitive behavioral tests. After completion of behavior, brains were collected for AHN analysis. Results: In mice treated with cocaine, preference for the cocaine-paired compartment (CPP memory) persisted over time. In addition, the cocaine-withdrawn mice overall displayed normal emotional behavior but they showed hippocampal-dependent cognitive impairment for novelty recognition (object and place) and spatial (reference and working) memory. The number of BrdU+ cells was unaffected, suggesting that cocaine withdrawal did not impair basal AHN. However, the cocaine-withdrawn mice excessively increased the number immature hippocampal neurons (doublecortin+) after behavioral training, in direct correlation with their cognitive performance, probably as a result of effortful learning. Conclusions: The CPP memory induced by cocaine remains unaltered after a prolonged period of abstinence, accompanied by defective acquisition of new learnings. Since the doublecortin+ neurons correlated with better cognitive performance in the cocaine-withdrawn mice, strategies that increase AHN could alleviate neurocognitive deficits induced by cocaine.Plan Propio Universidad de Málaga Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Anxiety associated with palatable food withdrawal is reversed by the selective FAAH inhibitor PF-3845: A regional analysis of the contribution of endocannabinoid signaling machinery

Objective: Consumption of energy-dense palatable "comfort" food can alleviate stress and negative emotions, while abrupt withdrawal from a palatable diet can worsen these symptoms, causing difficulties with adherence to weight-loss diets. Currently, no pharmacological treatment is effective for obesity-related anxiety, so we investigated the endocannabinoid system (ECS), and specifically the fatty acid amide hydrolase (FAAH), as an interesting emerging target in this context because of its key role in the regulation of both energy homeostasis and emotional behavior. Methods: Rats were subjected to exposure and subsequent abstinence from a palatable cafeteria diet. During abstinence period, rats were treated with the selective FAAH inhibitor PF-3845 (10 mg/kg; intraperitoneal administration every other day). Results: Abstinent rats displayed an anxiogenic-like behavior and changes in the proteins of ECS signaling machinery in brain areas involved both in anxiety and food intake regulation. In particular, withdrawal caused a reduction of the expression of cannabinoid receptors in the nucleus accumbens and of enzymes diacylglycerol lipase alpha and monoacylglycerol lipase (MAGL) in the amygdala. Pharmacological inhibition of FAAH exerted an anxiolytic-like effect in abstinent animals and increased both MAGL expression in amygdala and CB2 expression in prefrontal cortex. Discussion: Overall, our results suggest that emotional disturbances associated with dieting are coupled with region-specific alterations in the cerebral expression of the ECS and that the enhancement of the endocannabinoid signaling by FAAH inhibition might represent a novel pharmacological strategy for the treatment of anxiety related to abstinence from palatable food.Funding for open access charge: Universidad de Málaga / CBUA European Regional DevelopmentFunds-European Union, Grant/Award Number:PI19/01577; Instituto de Salud Carlos III,Grant/Award Number: RETICS; Ministerio deCiencia e Innovaci on, Grant/Award Number:ERDF-EU RD16/0017/0001; Ministerodell'Università e della Ricerca, Grant/AwardNumber: 2012JTX3KL; PNRR-RomeTechnopole-FP

Plasma endocannabinoid alterations as a link in the comorbidity of Alzheimer's disease and type 2 diabetes mellitus.

Over the last several years, studies have suggested a role of endocannabinoids such as 2-AG and 2-OG in the impairment of β-cell function and insulin secretion, as well as in the control of lipid and glucose metabolism in the periphery. Besides, alterations in the endocannabidiome are associated with the development of dementia. Since type 2 diabetes mellitus (T2DM) is an established risk factor for late-life cognitive decline, we sought to evaluate the possible link between the alterations in plasma endocannabinoids as potential biomarkers of cognitive decline in elderly patients with T2DM. In the present study, we evaluated the plasma levels of endocannabinoids in a cohort of elder controls and patients suffering from T2DM, with either mild cognitive impairment (MCI) or Alzheimer’s disease (AD). The cognitive performance of these patients was evaluated at the beginning of the study and their regional brain metabolic activity was assessed by PET-18FDG. We found that T2DM patients showed decreased levels of brain metabolic activity determined by PET-18FDG in the inferior parietal lobe, caudate, and thalamus, which were decreased and related to poor cognitive performance shown by both BLESSED and MMSE tests. Segregation of patients according to their cognitive status (MCI or AD) showed lower basal metabolism in the aforementioned regions, which was exacerbated in patients with AD and T2DM comorbidity. Correlation analysis showed plasma levels of the endocannabinoids 2-AG, 2-LG, and 2-OG were inversely related to brain metabolism in these areas, as well as to worse BLESSED and MMSE scores. Our results depict that plasma endocannabinoids are potential biomarkers linking the development of cognitive decline to the occurrence of T2DM.Consejería de Universidad, Investigación e Innovación, Junta de Andalucía, grant number PI21/00291. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Antipsychotic Medication Influences the Discriminative Value of Acylethanolamides as Biomarkers of Substance Use Disorder.

Plasma acylethanolamides (NAEs), including the endocannabinoid anandamide (AEA), have been proposed as circulating biomarkers of substance use disorders. However, the concentration of these lipid transmitters might be influenced by the use of drugs prescribed for either the treatment of addiction or the associated psychiatric co-morbidities such as psychosis. As an example, neuroleptics, used for attenuation of psychotic symptoms and sedation, might theoretically interfere with the monoamine-mediated production of NAEs, obstructing the interpretation of plasma NAEs as clinical biomarkers. To solve the lack of information on the impact of neuroleptics on the concentration of NAEs, we evaluated the concentrations of NAEs in a control group and compared them to those present in (a) substance use disorders (SUD) patients that are not prescribed with neuroleptics, and (b) SUD patients (both alcohol use disorder and cocaine use disorder patients) using neuroleptics. The results demonstrate that SUD patients exhibited greater concentrations of NAEs than the control population, affecting all species with the exception of stearoylethanolamide (SEA) and palmitoleoylethanolamide (POEA). Neuroleptic treatment enhanced the concentrations of NAEs, especially those of AEA, linoleoylethanolamide (LEA), and oleoylethanolamide (OEA). This effect of neuroleptic treatment was observed independently of the drug addiction that motivated the demand for treatment (either alcohol or cocaine). This study remarks the need to control the current use of psychotropic medication as a potential confounding variable when considering the use of NAEs as biomarkers in SUDPartial funding for open access charge: Universidad de Málag

Irrigation with saline water on pineapple grown in the semi-arid of bahia state

We aimed to evaluate the effects of different irrigation depths with saline water on growth, yield, water-use efficiency, and fruit quality of ‘Pérola’ pineapple plant grown in the semi-arid of Bahia state. The experiment was carried out in a randomized block design with five treatments which represented the irrigation depths: 100% of crop evapotranspiration (ETc) with irrigation water of 0.75 dS m-1 in electrical conductivity (ECiw); and 50, 75,100, and 125% of ETc with water of 3.6 dS m-1 in ECiw. Pineapples were grown under field conditions watered by drip irrigation in which pressure compensating emitters had 8 L h-1 flow rate. We observed that the irrigation depth 100% of ETc with water of 0.75 and 3.6 dS m-1 in ECiw provides higher pineapple yields under the semi-arid conditions of this study, and the chemical quality of the fruits are up to commercial standards, except when applying 125% of ETc with water of 3.6 dS m-1 in ECiw

Sex-Dimorphic Behavioral Alterations and Altered Neurogenesis in U12 Intron Splicing-Defective Zrsr1 Mutant Mice

Mutant mice with respect to the splicing factor Zrsr1 present altered spermatogenesis and infertility. To investigate whether Zrsr1 is involved in the homeostatic control that the hypothalamus exerts over reproductive functions, we first analyzed both differential gene and isoform expression and alternative splicing alterations in Zrsr1 mutant (Zrsr1mu) hypothalamus; second, we analyzed the spontaneous and social behavior of Zrsr1mu mice; and third, we analyzed adult cell proliferation and survival in the Zrsr1mu hypothalamus. The Zrsr1mu hypothalamus showed altered expression of genes and isoforms related to the glutathione metabolic process, synaptonemal complex assembly, mRNA transport, and altered splicing events involving the enrichment of U12-type intron retention (IR). Furthermore, increased IR in U12-containing genes related with the prolactin, progesterone, and gonadotropin-releasing hormone (GnRH) reproductive signaling pathway was observed. This was associated with a hyperactive phenotype in both males and females, with an anxious phenotype in females, and with increased social interaction in males, instead of the classical aggressive behavior. In addition, Zrsr1mu females but not males exhibited reduced cell proliferation in both the hypothalamus and the subventricular zone. Overall, these results suggest that Zrsr1 expression and function are relevant to organization of the hypothalamic cell network controlling behavior