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Biology subjects

Cole, M.

Publications and source records attributed to Cole, M..

7 recordsLinked to original sources

Effects of Nicotine and THC Vapor Inhalation Administered by An Electronic Nicotine Delivery System (ENDS) in Male Rats

BackgroundElectronic nicotine delivery systems (ENDS, e-cigarettes) are increasingly used for the self-administration of nicotine by various human populations, including previously nonsmoking adolescents. Studies in preclinical models are necessary to evaluate health impacts of ENDS including the development of nicotine addiction, effects of ENDS vehicles, flavorants and co-administered psychoactive substances such as {triangleup}9-tetrahydrocannabinol (THC). This study was conducted to validate a rat model useful for the study of nicotine effects delivered by inhalation of vapor created by ENDS. MethodsMale Sprague-Dawley rats (N=8) were prepared with radiotelemetry devices for the reporting of temperature and activity. Experiments subjected rats to inhalation of vapor generated by an electronic nicotine delivery system (ENDS) adapted for rodents. Inhalation conditions included vapor generated by the propylene glycol (PG) vehicle, Nicotine (1, 10, 30 mg/mL in the PG) and THC (12.5, 25 mg/mL). ResultsNicotine inhalation increased spontaneous locomotion and decreased body temperature of rats. Pretreatment with the nicotinic cholinergic receptor antagonist mecamylamine (2 mg/kg, i.p.) prevented stimulant effects of nicotine vapor inhalation and attenuated the hypothermic response. Combined inhalation of nicotine and THC resulted in apparently independent effects which were either additive (hypothermia) or opposed (activity). ConclusionsThese studies provide evidence that ENDS delivery of nicotine via inhalation results in nicotine-typical effects on spontaneous locomotion and thermoregulation in male rats. Effects were blocked by a nicotinic antagonist, demonstrating mechanistic specificity. This system will therefore support additional studies of the contribution of atomizer/wick design, vehicle constituents and/or flavorants to the effects of nicotine administered by ENDS.

pharmacology and toxicology

Single-cell transcriptomics identifies drivers of local inflammation in multiple sclerosis

Cerebrospinal fluid (CSF) protects the central nervous system (CNS) and analyzing CSF aids the diagnosis of CNS diseases, but our understanding of CSF leukocytes remains superficial. Here, we firstly provide a transcriptional map of single leukocytes in CSF compared to blood. Leukocyte composition and transcriptome were compartment-specific with CSF-enrichment of myeloid dendritic cells and a border-associated phenotype of monocytes.\n\nWe secondly tested how multiple sclerosis (MS) - an autoimmune disease of the CNS - affected both compartments. MS increased transcriptional diversity in blood, while it preferentially increased cell type diversity in CSF. In addition to the known expansion of B lineage cells, we identified an increase of cytotoxic-phenotype and follicular T helper (TFH) cells in the CSF. In mice, TFH cells accordingly promoted B cell infiltration into the CNS and severity of MS animal models. Immune mechanisms in MS are thus highly compartmentalized and indicate local T/B cell interaction.

immunology

Analysis and comparison of genome editing using CRISPResso2

Genome editing technologies are rapidly evolving, and analysis of deep sequencing data from target or off-target regions is necessary for measuring editing efficiency and evaluating safety. However, no software exists to analyze base editors, perform allele-specific quantification or that incorporates biologically-informed and scalable alignment approaches. Here, we present CRISPResso2 to fill this gap and illustrate its functionality by experimentally measuring and analyzing the editing properties of six genome editing agents.

bioinformatics

Δ9-tetrahydrocannabinol Attenuates Oxycodone Self-Administration Under Extended Access Conditions

Growing nonmedical use of prescription opioids is a global problem, motivating research on ways to reduce use and combat addiction. Medical cannabis (\"medical marijuana\") legalization has been associated epidemiologically with reduced opioid harms and cannabinoids have been shown to modulate effects of opioids in animal models. This study was conducted to determine if {Delta}9-tetrahydrocannabinol (THC) enhances the behavioral effects of oxycodone.\n\nMale rats were trained to intravenously self-administer (IVSA) oxycodone (0.15 mg/kg/infusion) during 1 h, 4 h or 8 h sessions. Following acquisition rats were exposed to THC by vapor inhalation (1 h and 8 h groups) or injection (0-10 mg/kg, i.p.; all groups) prior to IVSA sessions. Fewer oxycodone infusions were obtained by rats following vaporized or injected THC compared with vehicle treatment prior to the session. Follow-up studies demonstrated parallel dose-dependent effects of THC, i.p., on self-administration of different per-infusion doses of oxycodone and a preserved loading dose early in the session. These patterns are inconsistent with behavioral suppression. Additional groups of male and female Wistar rats were assessed for nociception following inhalation of vaporized THC (50 mg/mL), oxycodone (100 mg/mL) or the combination. Tail withdrawal latency was increased more by the THC/oxycodone combination compared to either drug alone. Similar additive antinociceptive effects were produced by injection of THC (5.0 mg/kg, i.p.) and oxycodone (2.0 mg/kg, s.c.). Together these data demonstrate additive effects of THC and oxycodone and suggest the potential use of THC to enhance therapeutic efficacy, and to reduce the abuse, of opioids.

neuroscience

Heterogeneity Within the Frontoparietal Control Network and its Relationship to the Default and Dorsal Attention Networks

The frontoparietal control network (FPCN) plays a central role in executive control. It has been predominantly viewed as a unitary domain general system. Here, we examined patterns of FPCN functional connectivity (FC) across multiple conditions of varying cognitive demands, in order to test for FPCN heterogeneity. We identified two distinct subsystems within the FPCN based on hierarchical clustering and machine learning classification analyses of within-FPCN FC patterns. These two FPCN subsystems exhibited distinct patterns of FC the default network (DN) and the dorsal attentional network (DAN). This 2-fold FPCN differentiation was observed across four independent data sets, across 9 different conditions (rest and 8 tasks), as well as in meta-analytic co-activation patterns. The extent of FPCN differentiation varied across conditions, suggesting flexible adaptation to task demands. These findings reveal a flexible and heterogeneous FPCN organization that may in part emerge from separable DN and DAN processing streams.

neuroscience

Repeated vapor inhalation of Δ9-tetrahydrocannabinol induces tolerance to hypothermia in female rats

RationaleA reduced effect of a given dose of {Delta}9-tetrahydrocannabinol (THC) emerges with repeated exposure to the drug. This tolerance can vary depending on THC dose, exposure chronicity and the behavioral or physiological measure of interest. A novel THC inhalation system based on e-cigarette technology has been recently shown to produce the hypothermic and antinociceptive effects of THC in rats.\n\nObjectiveTo determine if tolerance to these effects can be produced with repeated vapor inhalation.\n\nMethodsGroups of male and female Wistar rats were exposed to 30 minutes of inhalation of the propylene glycol (PG) vehicle or THC (200 mg/mL in PG) two or three times per day for four days. Rectal temperature changes and nociception were assessed after the first exposure on the first and fourth days of repeated inhalation.\n\nResultsFemale, but not male, rats developed tolerance to the hypothermic and antinociceptive effects of THC after four days of twice-daily THC vapor inhalation. Thrice daily inhalation for four days resulted in tolerance in both male and female rats. The plasma THC levels reached after a 30 minute inhalation session did not differ between the male and female rats.\n\nConclusionsRepeated daily THC inhalation induces tolerance in female and male rats, providing further validation of the vapor inhalation method for preclinical studies.\n\nAbbreviationsPG, propylene glycol; THC; {Delta}9tetrahydrocannabinol;

neuroscience

Effects Of Δ9-THC And Cannabidiol Vapor Inhalation In Male And Female Rats

Previous studies report sex differences in some, but not all, responses to cannabinoids in rats. The majority of studies use parenteral injection, however most human use is via smoke inhalation and, increasingly, vapor inhalation. The aim of this study was to compare thermoregulatory and locomotor responses to inhaled {Delta}9-tetrahydrocannabinol (THC), cannabidiol (CBD) and their combination using an e-cigarette based model in male and female rats.\n\nGroups of male and female Sprague-Dawley rats (N=8 per group) were implanted with radiotelemetry devices for the assessment of body temperature and locomotor activity. Animals were then exposed to THC or CBD vapor (4 puffs/5 minutes) using a propylene glycol (PG) vehicle. THC dose was adjusted via the concentration in the vehicle (12.5-200 mg/ml) and CBD (100, 400 mg/mL) dose was also adjusted by varying the inhalation duration (10-40 minutes). Anti-nociception was evaluated using a tail-withdrawal assay following vapor inhalation.\n\nTHC inhalation reduced body temperature and increased tail-withdrawal latency in both sexes equivalently and in a concentration-dependent manner. Female temperature, activity and anti-nociceptive responses to THC did not differ between the estrus and diestrus phases. CBD inhalation alone induced hypothermia and suppressed locomotor activity in both males and females. Co-administration of THC with CBD, in a 1:4 ratio, significantly decreased temperature and activity in an approximately additive manner and to similar extent in each sex.\n\nIn summary the inhalation of THC or CBD, alone and in combination, produces approximately equivalent effects in male and female rats. Sex differences were subtle and mostly reflected in a more prolonged body temperature disruption in females.

pharmacology and toxicology