Cytotoxic and Antitumoral Effects of Methanolic Extracts of Avocado Fruit Mesocarp in Colorectal Cancer Cell Line HT29.

Colorectal cancer is a widespread neoplasia with high ratios of chemoresistance. Phytochemicals in plant-based extracts could be useful to treat colorectal cancer, and/or reduce chemoresistance. Methanolic extract of avocado mesocarp (MEAM) has demonstrated antitumoral properties, depending on the fruit ripening stage (RS). The aim of this study was to analyze the effects of methanolic extracts of "Hass" avocado fruit at different RS on cytotoxicity, antioxidative, anti-inflammatory, anti-invasive, cell cycle, and epithelial-mesenchymal transition inhibition in colorectal adenocarcinoma cell line HT29. The MEAM showed an increasing concentration of total phenolic compounds as the RS progressed, which was correlated with antioxidant capacity measured by the Ferric Reducing Antioxidant Power assay but not with the 2.2-diphenyl-1-picrylhydrazyl assay. The specific phenolic compounds of MEAM were determined by high-performance liquid chromatography, and it was found that concentrations of epicatechin decreased while concentrations of chlorogenic acid increased as the RS progressed. The HT29 cell line was treated with MEAM for 48 h, and all MEAM had a cytotoxic effect, reported by MTT assay, nevertheless, the strongest effect was associated with the presence of chlorogenic acid. MEAM induced apoptosis and cell cycle arrest in phase G0/G1, reported by flow cytometry. Moreover, MEAM inhibited cell migration evidenced by the wound healing assay. On the other hand, MEAM significantly reduced expression of mRNA of tumor necrosis factor-alpha and cyclooxygenase 2. These effects comprise important inhibition of some hallmarks of cancer. This, in turn, may provide interesting guidelines for developing antitumoral intervention agents.

Morphine-context associative memory and locomotor sensitization in mice are modulated by sex and context in a dose-dependent manner.

Sex differences in opioid use, development of opioid used disorder, and relapse behaviors indicate potential variations in opioid effects between men and women. The locomotor and interoceptive effects of opioids play essential roles in opioid addiction, and uncovering the neural mechanisms underlying these effects remain crucial for developing effective treatments. In this study, we examined the dose-dependent effects of morphine on locomotor sensitization and the strength and stability of morphine-context associations in the conditioned place preference (CPP) paradigm in male and female mice, as well as the relationships between these measures. We observed that while CPP is similar between sexes, the locomotor effects of repeated morphine administration and withdrawal differentially contributed to the strength and stability of morphine-context associations. Specifically, females exhibited higher morphine-induced hyperlocomotion than males regardless of the context in which morphine was experienced. Greater locomotor sensitization to morphine in females than males emerged in a dose-dependent manner only when there was sufficient context information for CPP to be established. Additionally, the relationships between the locomotor effects of morphine and the strength and stability of CPP were different in males and females. In females, positive acute and sensitizing locomotor effects of morphine were correlated with a higher CPP score, while the opposite direction of this relationship was found in males. These results suggest that different aspects of the subjective experience of morphine intoxication and withdrawal are important for morphine abuse-related behaviors and highlight the importance of sex-specific responses in the context of opioid addiction.

Impact of Drying Process on the Phenolic Profile and Antioxidant Capacity of Raw and Boiled Leaves and Inflorescences of Chenopodium berlandieri ssp. berlandieri.

C. berlandieri ssp. berlandieri (C. berlandieri) is one of the most common members of the group of plants known as quelites, which are dark leafy greens widely consumed in Mexico. This study aimed to evaluate the impact of two drying procedures (oven drying and freeze-drying/lyophilization) on the polyphenolic composition, antioxidant capacity, and proximal chemical analysis of C. berlandieri leaves and inflorescences (raw or boiled). The results indicated that the raw freeze-dried samples had higher amounts (p < 0.05) of total phenolic compounds, total flavonoids, and antioxidant capacity, mainly in the inflorescence. The oven-dried samples showed an increased concentration of polyphenols after boiling, while the lyophilized samples showed a slightly decreased concentration. The drying process was observed to have little impact on the proximal chemical composition. Quantification by UPLC-DAD-ESI-QToF/MS identified up to 23 individual phenolic compounds, with freeze-dried samples showing higher amounts of individual compounds compared with oven-dried. Procyanidin B2 was found exclusively in the inflorescences. The inflorescences have a higher content of phenolic compounds and greater antioxidant capacity than the leaves. Regardless of the drying process, the leaves and inflorescences of C. berlandieri contain an interesting variety of phenolic compounds that may have beneficial effects on health.

Comparison of Phenolic Compounds and Evaluation of Antioxidant Properties of Porophyllum ruderale (Jacq.) Cass (Asteraceae) from Different Geographical Areas of Queretaro (Mexico).

Porophyllum ruderale (P. ruderale) is a well-known Mexican plant from the group of "Quelites", widely consumed plant species used for several food and medicinal purposes. As the production is very heterogeneous and the diverse agroclimatic conditions significantly impact the plant's phytochemical composition, this research aimed to compare the phenolic compound composition and the antioxidant capacity of the P. ruderale plant from three different collection sites (Queretaro, Landa de Matamoros, and Arroyo Seco) in the State of Queretaro (Mexico). Plants collected from Queretaro displayed the lowest total phenolic compounds, flavonoids, and condensed tannins, reflected in a lower antioxidant capacity (DPPH, FRAP, ABTS), compared to the other collection places. Flavones (epicatechin and epigallocatechin gallate) were the most abundant (36.1-195.2 µg equivalents/g) phenolics quantified by HPLC-DAD, while 31 compounds were identified by UHPLC-DAD-QToF/MS-ESI. Most compounds were linked to biological mechanisms related to the antioxidant properties of the leaves. A PCA analysis clustered Landa de Matamoros and Arroyo Seco into two groups based on flavones, hydroxybenzoic acids, the antioxidant capacity (ABTS and DPPH), and total phenolic compounds, the main contributors to its variation. The results indicated contrasting differences in the polyphenolic composition of collected P. ruderale in Queretaro, suggesting the need to standardize and select plants with favorable agroclimatic conditions to obtain desirable polyphenolic compositions while displaying potential health benefits.

Comparison of Phytochemical Composition and Untargeted Metabolomic Analysis of an Extract from Cnidoscolus aconitifolius (Mill.) I. I. Johnst and Porophyllum ruderale (Jacq.) Cass. and Biological Cytotoxic and Antiproliferative Activity In Vitro.

Cnidoscolus aconitifolius (CA) and Porophyllum ruderale (PR) are representative edible plants that are a traditional food source in Mexico. This research aimed to analyze the phytochemical composition and untargeted metabolomics analysis of CA and PR and evaluate their antiproliferative effect in vitro. The phytochemical composition (UPLC-DAD-QToF/MS-ESI) identified up to 38 polyphenols and selected organic acids that were clustered by the untargeted metabolomics in functional activities linked to indolizidines, pyridines, and organic acids. Compared with PR, CA displayed a higher reduction in the metabolic activity of human SW480 colon adenocarcinoma cells (LC50: 10.65 mg/mL), and both extracts increased the total apoptotic cells and arrested cell cycle at G0/G1 phase. PR increased mRNA Apc gene expression, whereas both extracts reduced mRNA Kras expression. Rutin/epigallocatechin gallate displayed the highest affinity to APC and K-RAS proteins in silico. Further research is needed to experiment on other cell lines. Results suggested that CA and PR are polyphenol-rich plant sources exhibiting antiproliferative effects in vitro.

Salivary gland tumor incidence in adult patients in a tertiary hospital in Mexico from 2008 to 2019.

OBJECTIVE: To determine the incidence of salivary gland tumors in a population of a tertiary hospital in the State of Mexico, and to describe demographic variables. METHOD: An observational, cross-sectional and retrospective study of salivary gland tumors reported in a tertiary hospital in the State of Mexico in the period 2008-2019 is presented. RESULTS: A prevalence of 0.049% was found. There was no difference between sex in the studied population. Benign salivary gland tumors were the most frequent (86.7%). The age range most affected was 51-60 years. The most frequently found tumor was the pleomorphic adenoma, followed by Warthin's tumor. There was 13.33% of sialolipomas, and one myoepithelioma. There were no cases of sublingual gland tumors or minor salivary glands. CONCLUSION: Tumors of the major salivary glands are infrequent tumors; population cases from a central Mexican state and their demographic characteristics are presented to contribute to the information found in local and international literature.

OBJETIVO: Determinar la incidencia de los tumores de glándulas salivales en una población de un hospital de tercer nivel en el Estado de México y describir variables demográficas. MATERIAL Y MÉTODOS: Se presenta un estudio observacional, transversal y retrospectivo de los tumores de glándulas salivales reportados en un hospital de tercer nivel en el Estado de México en el periodo 2008-2019. RESULTADOS: Se encontró una prevalencia del 0.049%. No hubo diferencia entre sexos en la población afectada. Los tumores de glándulas salivales benignos fueron los más frecuentes (86.7%). El rango de edad mayormente afectado fue el de 51-60 años. El tumor más frecuentemente encontrado fue el adenoma pleomorfo, seguido por tumor de Warthin. Se presentó un 13.33% de sialolipomas y un mioepitelioma. No se presentó ningún caso de tumores de glándulas sublinguales ni glándulas salivales menores. CONCLUSIÓN: Los tumores de glándulas salivales mayores son tumores infrecuentes, se exponen casos de población de un Estado del centro de México y sus características demográficas para contribuir a la información encontrada en literatura local e internacional.

Valence and salience encoding by parallel circuits from the paraventricular thalamus to the nucleus accumbens.

The anterior and posterior subregions of the paraventricular thalamus (aPVT and pPVT, respectively) play unique roles in learned behaviors, from fear conditioning to alcohol/drug intake, potentially through differentially organized projections to limbic brain regions including the nucleus accumbens medial shell (mNAcSh). Here, we found that the aPVT projects broadly to the mNAcSh and that the aPVT-mNAcSh circuit encodes positive valence, such that in vivo manipulations of the circuit modulated both innately programmed and learned behavioral responses to positively and negatively valenced stimuli, particularly in females. Further, the endogenous activity of aPVT presynaptic terminals in the mNAcSh was greater in response to positively than negatively valenced stimuli, and the probability of synaptic glutamate release from aPVT neurons in the mNAcSh was higher in females than males. In contrast, we found that the pPVT-mNAcSh circuit encodes stimulus salience regardless of valence. While pPVT-mNAcSh circuit inhibition suppressed behavioral responses in both sexes, circuit activation increased behavioral responses to stimuli only in males. Our results point to circuit-specific stimulus feature encoding by parallel PVT-mNAcSh circuits that have sex-dependent biases in organization and function.

Deferred Action for Childhood Arrivals (DACA): Maximizing Impacts in Medical Education and Health Care.

Introduction: Deferred Action for Childhood Arrivals (DACA) provides a path for individuals who are undocumented to join the physician workforce. Indeed, recipients of DACA can play an important role in addressing health inequities in medicine. Although DACA has been in place since 2012, many medical schools remain unaware of it or are hesitant to consider recipients for admission. In a similar vein, the premedical community, including those with DACA status, may be unaware of their eligibility and the steps necessary to pursue medicine. Further education and outreach are needed to achieve institutional policies conducive to the inclusion and success of those undocumented in medicine. Methods: We created an hour-long workshop to empower learners with key knowledge relevant to DACA policy and its impact on medicine. We evaluated the workshop through pre- and postworkshop questionnaires assessing participant knowledge and attitudes based on the theory of planned behavior (TPB). Results: A total of 112 participants engaged in our workshop. Ninety-one pretests and 61 posttests were completed by attendees. Data revealed a significant increase in performance on all knowledge-based and TPB questions, including intention to participate in future policy development. Moreover, participants reported appreciating the interactive nature of the session and expressed feelings of empowerment by their newfound knowledge base. Discussion: This workshop provides a promising foundation from which conversations and progress regarding DACA-related medical education policy can begin. Specifically, the workshop engages participants in the process of identifying actionable steps for overcoming barriers to inclusion and support.

Improving the Efficacy and Accessibility of Intracranial Viral Vector Delivery in Non-Human Primates.

Non-human primates (NHPs) are precious resources for cutting-edge neuroscientific research, including large-scale viral vector-based experimentation such as optogenetics. We propose to improve surgical outcomes by enhancing the surgical preparation practices of convection-enhanced delivery (CED), which is an efficient viral vector infusion technique for large brains such as NHPs'. Here, we present both real-time and next-day MRI data of CED in the brains of ten NHPs, and we present a quantitative, inexpensive, and practical bench-side model of the in vivo CED data. Our bench-side model is composed of food coloring infused into a transparent agar phantom, and the spread of infusion is optically monitored over time. Our proposed method approximates CED infusions into the cortex, thalamus, medial temporal lobe, and caudate nucleus of NHPs, confirmed by MRI data acquired with either gadolinium-based or manganese-based contrast agents co-infused with optogenetic viral vectors. These methods and data serve to guide researchers and surgical team members in key surgical preparations for intracranial viral delivery using CED in NHPs, and thus improve expression targeting and efficacy and, as a result, reduce surgical risks.

Phenolic profile and antioxidant capacity of Pithecellobium dulce (Roxb) Benth: a review.

Pithecellobium dulce (Roxb) Benth (P. dulce), known as "guamúchil", is a tree native to the American continent. Various parts of the tree are used in traditional medicine, primarily for treating gastrointestinal disorders. The phenolic compounds and antioxidant capacity of this plant are largely responsible for the beneficial health effects attributed to it. A number of authors have studied the antioxidant capacity and phenolic compounds of the aril, seed, leaf and root of P. dulce using various methodologies, which can differ considerably in variables such as environmental factors, type of drying, temperature, the way the sample is stored, and the use of different solvents in the various extraction methods. Even methods of quantification by HPLC vary tremendously. This paper summarizes the existing research carried out to date on determining the phenolic profile and antioxidant capacity of P. dulce.

Anatomy and Function of the Primate Entorhinal Cortex.

The entorhinal cortex (EC) is a critical element of the hippocampal formation located within the medial temporal lobe (MTL) in primates. The EC has historically received attention for being the primary mediator of cortical information going into and coming from the hippocampus proper. In this review, we highlight the significance of the EC as a major player in memory processing, along with other associated structures in the primate MTL. The complex, convergent topographies of cortical and subcortical input to the EC, combined with short-range intrinsic connectivity and the selective targeting of EC efferents to the hippocampus, provide evidence for subregional specialization and integration of information beyond what would be expected if this structure were a simple conduit of information for the hippocampus. Lesion studies of the EC provide evidence implicating this region as critical for memory and the flexible use of complex relational associations between experienced events. The physiology of this structure's constituent principal cells mirrors the complexity of its anatomy. EC neurons respond preferentially to aspects of memory-dependent paradigms including object, place, and time. EC neurons also show striking spatial representations as primates explore visual space, similar to those identified in rodents navigating physical space. In this review, we highlight the great strides that have been made toward furthering our understanding of the primate EC, and we identify paths forward for future experiments to provide additional insight into the role of this structure in learning and memory.

Quantum Dot Labelling of Tepary Bean (Phaseolus acutifolius) Lectins by Microfluidics.

Lectins are bioactive proteins with the ability to recognize cell membrane carbohydrates in a specific way. Diverse plant lectins have shown diagnostic and therapeutic potential against cancer, and their cytotoxicity against transformed cells is mediated through the induction of apoptosis. Previous works have determined the cytotoxic activity of a Tepary bean (Phaseolus acutifolius) lectin fraction (TBLF) and its anti-tumorigenic effect on colon cancer. In this work, lectins from the TBLF were additionally purified by ionic-exchange chromatography. Two peaks with agglutination activity were obtained: one of them was named TBL-IE2 and showed a single protein band in two-dimensional electrophoresis; this one was thus selected for coupling to quantum dot (QD) nanoparticles by microfluidics (TBL-IE2-QD). The microfluidic method led to low sample usage, and resulted in homogeneous complexes, whose visualization was achieved using multiphoton and transmission electron microscopy. The average particle size (380 nm) and the average zeta potential (-18.51 mV) were determined. The cytotoxicity of the TBL-IE2 and TBL-IE2-QD was assayed on HT-29 colon cancer cells, showing no differences between them (p ≤ 0.05), where the LC50 values were 1.0 × 10-3 and 1.7 × 10-3 mg/mL, respectively. The microfluidic technique allowed control of the coupling between the QD and the protein, substantially improving the labelling process, providing a rapid and efficient method that enabled the traceability of lectins. Future studies will focus on the potential use of the QD-labelled lectin to recognize tumor tissues.

Effect on nutritional markers of a model of aberrant crypt foci induced by azoxymethane and sodium dextran sulfate in Sprague Dawley rats / Efecto sobre marcadores nutricionales de un modelo de focos de criptas aberrantes inducidos por azoximetano y dextrano de sulfato sódico en ratas Sprague Dawley

Introduction: aberrant crypt foci (ACF) are colon preneoplastic lesions that can be used as a tool to study preventive processes for colorectal cancer (CRC). This model consists of initiation induced by azoxymethane (AOM) and promoted by sodium dextran sulfate (DSS), simulating human colonic carcinogenesis in a rat model. There is no direct information on the effects of this process on nutritional markers. Objective: to determine the effect on nutritional markers after the induction of ACF by AOM/DSS in a rat model. Methods: ACF were induced in 24 four-week-old Sprague Dawley male rats by administration of 2 AOM injections (10 mg/kg) and 7 days of 2% DSS in their drinking water. Body weight gain, food and fluid intake, weight of sacrificial organs, nutritional biochemical profiles, liver and kidney toxicity were evaluated. Cell counts in blood were also performed and histological sections evaluated in specific organs. The model was confirmed with identification and counts of ACF. Half of the rats were sacrificed at the sub-chronic stage and the rest at the chronic stage. Results: at the sub-chronic stage, changes in the liver and colon weight, and in the lymphocyte count were observed. For both stages, histopathological damage was observed in liver, kidney and colon, along with alterations in serum glucose levels. Conclusions: the model for proposed ACF can be used at the sub-chronic stage without the need for observation at the chronic stage. More research is needed to determine the mechanism of the observed effects

Introducción: los focos de criptas aberrantes (ACF) son lesiones preneoplásicas en colon que pueden ser utilizados como herramienta para estudiar procesos preventivos para el cáncer colorectal (CCR). Este modelo consiste en la iniciación inducida por azoximetano (AOM) y promovida por dextrano sulfato sódico (DSS) simulando una carcinogénesis colónica humana en un modelo de rata. No existe información directa de los efectos sobre marcadores nutricios para este proceso. Objetivo: determinar el efecto sobre marcadores nutricios tras la inducción de ACF por AOM/DSS en un modelo de rata. Métodos: se utilizaron veinticuatro ratas machos Sprague Dawley de 4 semanas para la inducción de ACF por administración de 2 inyecciones de AOM (10 mg/kg) y 7 días de DSS al 2% en el agua para beber. Se evaluó la ganancia de peso corporal, el consumo de alimento y de líquidos, el peso de órganos al sacrificio, perfiles bioquímicos nutricios, de toxicidad hepática y renal. Asimismo, se realizaron conteos celulares en sangre y se evaluaron cortes histológicos en órganos específicos. El modelo se confirmó con la identificación y conteos de ACF. Se sacrificó la mitad de las ratas en etapa subcrónica y las demás en etapa crónica. Resultados: en la etapa subcrónica se observaron cambios entre grupos en el peso del hígado y colon, y en el conteo de linfocitos. En ambas etapas se observaron daños histopatológicos en hígado, riñón y colon, así como alteraciones en los niveles de glucosa sérica. Conclusiones: el modelo para ACF propuesto puede ser utilizado en etapa subcrónica sin necesidad de llevarlo a tiempo crónico. Es necesaria más investigación para determinar el mecanismo de los efectos observados

Effect on nutritional markers of a model of aberrant crypt foci induced by azoxymethane and sodium dextran sulfate in Sprague Dawley rats.

INTRODUCTION: Introduction: aberrant crypt foci (ACF) are colon preneoplastic lesions that can be used as a tool to study preventive processes for colorectal cancer (CRC). This model consists of initiation induced by azoxymethane (AOM) and promoted by sodium dextran sulfate (DSS), simulating human colonic carcinogenesis in a rat model. There is no direct information on the effects of this process on nutritional markers. Objective: to determine the effect on nutritional markers after the induction of ACF by AOM/DSS in a rat model. Methods: ACF were induced in 24 four-week-old Sprague Dawley male rats by administration of 2 AOM injections (10 mg/kg) and 7 days of 2% DSS in their drinking water. Body weight gain, food and fluid intake, weight of sacrificial organs, nutritional biochemical profiles, liver and kidney toxicity were evaluated. Cell counts in blood were also performed and histological sections evaluated in specific organs. The model was confirmed with identification and counts of ACF. Half of the rats were sacrificed at the sub-chronic stage and the rest at the chronic stage. Results: at the sub-chronic stage, changes in the liver and colon weight, and in the lymphocyte count were observed. For both stages, histopathological damage was observed in liver, kidney and colon, along with alterations in serum glucose levels. Conclusions: the model for proposed ACF can be used at the sub-chronic stage without the need for observation at the chronic stage. More research is needed to determine the mechanism of the observed effects.

INTRODUCCIÓN: Introducción: los focos de criptas aberrantes (ACF) son lesiones preneoplásicas en colon que pueden ser utilizados como herramienta para estudiar procesos preventivos para el cáncer colorectal (CCR). Este modelo consiste en la iniciación inducida por azoximetano (AOM) y promovida por dextrano sulfato sódico (DSS) simulando una carcinogénesis colónica humana en un modelo de rata. No existe información directa de los efectos sobre marcadores nutricios para este proceso. Objetivo: determinar el efecto sobre marcadores nutricios tras la inducción de ACF por AOM/DSS en un modelo de rata. Métodos: se utilizaron veinticuatro ratas machos Sprague Dawley de 4 semanas para la inducción de ACF por administración de 2 inyecciones de AOM (10 mg/kg) y 7 días de DSS al 2% en el agua para beber. Se evaluó la ganancia de peso corporal, el consumo de alimento y de líquidos, el peso de órganos al sacrificio, perfiles bioquímicos nutricios, de toxicidad hepática y renal. Asimismo, se realizaron conteos celulares en sangre y se evaluaron cortes histológicos en órganos específicos. El modelo se confirmó con la identificación y conteos de ACF. Se sacrificó la mitad de las ratas en etapa subcrónica y las demás en etapa crónica. Resultados: en la etapa subcrónica se observaron cambios entre grupos en el peso del hígado y colon, y en el conteo de linfocitos. En ambas etapas se observaron daños histopatológicos en hígado, riñón y colon, así como alteraciones en los niveles de glucosa sérica. Conclusiones: el modelo para ACF propuesto puede ser utilizado en etapa subcrónica sin necesidad de llevarlo a tiempo crónico. Es necesaria más investigación para determinar el mecanismo de los efectos observados.

Preventive Effect of an Infusion of the Aqueous Extract of Chaya Leaves (Cnidoscolus aconitifolius) in an Aberrant Crypt Foci Rat Model Induced by Azoxymethane and Dextran Sulfate Sodium.

Aberrant crypt foci (ACF) is the precursor lesion of colorectal carcinogenesis (CRC), one of the most common malignancies in the world. Many studies have reported that people with higher phytochemical intake are at a reduced risk of developing ACF. One example of the botanical potential of preventive plant products is Cnidoscolus aconitifolius (CA), commonly known as Chaya. This study evaluated the phenolic profile of CA and the effects of the daily consumption of CA leaf infusion on the formation of ACF, histopathological lesions, and molecular biomarkers after azoxymethane (AOM) and dextran sulfate sodium (DSS) induced premalignant colon lesions in rats treated with for 16 and 32 weeks. The phenolic composition of the CA infusion was identified by reversed phase-high performance liquid chromatography-diode array detection (RP-HPCC-DAD). After sacrifice, a 4 cm segment was collected from the distal part of the colon and stained with methylene blue to look for ACF. Furthermore, 4 µm of colon, liver, and kidney was collected and stained with hematoxylin and eosin for histopathological analysis, along with 7 µm of colon for immunohistochemistry analysis. Eleven phenolic compounds were identified in the infusions, and ACF formation was reduced by 29.5% at the subchronic and by 64.6% at chronic stages. Lesions on kidney, liver, and colon tissue were also reduced. Our data suggest that CA treatment has preventive effects against AOM-/DSS-induced premalignant colon lesions in colon rats at the promotion level, inhibiting the cell proliferation of early neoplastic lesions and colonic inflammation through the decrease of ß-catenin by 41.8% at the subchronic stage and 29% at the chronic stage, along with a 46.2% reduction of cyclooxygenase 2 (COX-2) at long term, despite a high expression of NF-κB (30.3% at the subchronic stage and 22.8% at the chronic stage).

Chemogenetic inhibition of direct pathway striatal neurons normalizes pathological, cue-induced reinstatement of drug-seeking in rats.

Addiction to drugs such as cocaine is marked by cycles of compulsive drug-taking and drug-seeking behavior. Although the transition to addiction is thought to recruit neural processes in dorsal striatum, little is known regarding the role of dorsal striatal projections to the substantia nigra (i.e. the direct pathway) in regulating these behaviors. Combining a Cre-recombinase-dependent chemogenetic approach with a cocaine self-administration paradigm that produces both low-risk and high-risk addiction phenotypes, we examined the effect of transiently decreasing direct pathway activity in the dorsomedial striatum on drug-taking and drug-seeking under conditions of normal and pathological drug use. Surprisingly, transient inhibition of direct pathway striatal neurons had no effect on several measures of addictive behavior during ongoing drug use, including loss of control over drug intake, high motivation to obtain drug and drug use despite negative consequences (i.e. drug use paired with foot shock). However, chemogenetic inhibition of these neurons during reinstatement reduced cue-induced drug-seeking, but only in the high-risk addiction phenotype group. Cue-induced reinstatement was relatively normal in the low-risk addiction phenotype group, as well as following reinstatement to cues associated with sucrose pellet consumption. These results demonstrate that dorsomedial direct pathway striatal neurons play a very specific role in addictive behaviors, which is to regulate the pathological drug-seeking that accompanies relapse.

Viral strategies for targeting cortical circuits that control cocaine-taking and cocaine-seeking in rodents.

Addiction to cocaine is a chronic disease characterized by persistent drug-taking and drug-seeking behaviors, and a high likelihood of relapse. The prefrontal cortex (PFC) has long been implicated in the development of cocaine addiction, and relapse. However, the PFC is a heterogeneous structure, and understanding the role of PFC subdivisions, cell types and afferent/efferent connections is critical for gaining a comprehensive picture of the contribution of the PFC in addiction-related behaviors. Here we provide an update on the role of the PFC in cocaine addiction from recent work that used viral-mediated optogenetic and chemogenetic tools to study the role of the PFC in drug-taking and drug-seeking behavior in rodents. Following overviews of rodent PFC neuroanatomy and of viral-mediated optogenetic and chemogenetic techniques, we review studies of manipulations within the PFC, followed by a review of work that utilized targeted manipulations to PFC inputs and outputs.

Medial Entorhinal Cortex Selectively Supports Temporal Coding by Hippocampal Neurons.

Recent studies have shown that hippocampal "time cells" code for sequential moments in temporally organized experiences. However, it is currently unknown whether these temporal firing patterns critically rely on upstream cortical input. Here we employ an optogenetic approach to explore the effect of large-scale inactivation of the medial entorhinal cortex on temporal, as well as spatial and object, coding by hippocampal CA1 neurons. Medial entorhinal inactivation produced a specific deficit in temporal coding in CA1 and resulted in significant impairment in memory across a temporal delay. In striking contrast, spatial and object coding remained intact. Further, we extended the scope of hippocampal phase precession to include object information relevant to memory and behavior. Overall, our work demonstrates that medial entorhinal activity plays an especially important role for CA1 in temporal coding and memory across time.

Fat mass obesity-associated (FTO) (rs9939609) and melanocortin 4 receptor (MC4R) (rs17782313) SNP are positively associated with obesity and blood pressure in Mexican school-aged children.

Childhood overweight and obesity are worldwide public health problems and risk factors for chronic diseases. The presence of SNP in several genes has been associated with the presence of obesity. A total of 580 children (8-13 years old) from Queretaro, Mexico, participated in this cross-sectional study, which evaluated the associations of rs9939609 (fat mass obesity-associated (FTO)), rs17782313 (melanocortin 4 receptor (MC4R)) and rs6548238 (transmembrane protein 18 (TMEM18)) SNP with obesity and metabolic risk factors. Overweight and obesity prevalence was 19·8 and 19·1 %, respectively. FTO, MC4R and TMEM18 risk allele frequency was 17, 9·8 and 89·5 %, respectively. A significant association between FTO homozygous and MC4R heterozygous risk alleles and obesity was found (OR 3·9; 95 % CI 1·46, 10·22, and OR 2·1; 95 % CI 1·22, 3·71; respectively). The FTO heterozygous subjects showed higher systolic and diastolic blood pressures, compared with the homozygous for the ancestral allele subjects. These results remain significant after considering adiposity as a covariate. The FTO and MC4R genotypes were not significantly associated with total cholesterol, HDL-cholesterol and insulin concentration. No association was found between TMEM18 risk allele and obesity and/or metabolic alterations. Our results show that, in addition to a higher BMI, there is also an association of the risk genotype with blood pressure in the presence of the FTO risk genotype. The possible presence of a risk genotype in obese children must be considered to offer a more comprehensive therapeutic approach in order to delay and/or prevent the development of chronic diseases.

Immediate and Complex Cardiovascular Adaptation to an Acute Alcohol Dose.

BACKGROUND: The detrimental effects of chronic heavy alcohol use on the cardiovascular system are well established and broadly appreciated. Integrated cardiovascular response to an acute dose of alcohol has been less studied. This study examined the early effects of an acute dose of alcohol on the cardiovascular system, with particular emphasis on system variability and sensitivity. The goal was to begin to understand how acute alcohol disrupts dynamic cardiovascular regulatory processes prior to the development of cardiovascular disease. METHODS: Healthy participants (N = 72, age 21 to 29) were randomly assigned to an alcohol, placebo, or no-alcohol control beverage condition. Beat-to-beat heart rate (HR) and blood pressure (BP) were assessed during a low-demand cognitive task prior to and following beverage consumption. Between-group differences in neurocardiac response to an alcohol challenge (blood alcohol concentration ~ 0.06 mg/dl) were tested. RESULTS: The alcohol beverage group showed higher average HR, lower average stroke volume, lower HR variability and BP variability, and increased vascular tone baroreflex sensitivity after alcohol consumption. No changes were observed in the placebo group, but the control group showed slightly elevated average HR and BP after beverage consumption, possibly due to juice content. At the level of the individual, an active alcohol dose appeared to disrupt the typically tight coupling between cardiovascular processes. CONCLUSIONS: A dose of alcohol quickly invoked multiple cardiovascular responses, possibly as an adaptive reaction to the acute pharmacological challenge. Future studies should assess how exposure to alcohol acutely disrupts or dissociates typically integrated neurocardiac functions.