Papers by Saoirse O'Sullivan
Pharmaceuticals
Cachexia syndrome, leading to reduced skeletal muscle and fat mass, is highly prevalent in cancer... more Cachexia syndrome, leading to reduced skeletal muscle and fat mass, is highly prevalent in cancer patients, resulting in further negative implications for these patients. To date, there is no approved therapy for cachexia syndrome. The objective of this study was to establish an in vitro model of cancer cachexia in mature human skeletal muscle myotubes, with the intention of exploiting the cell model to assess potential cachexia therapeutics, specifically cannabinoid related drugs. Having cultured and differentiated primary human muscle myoblasts to mature myotubes, we successfully established two cancer cachexia models using conditioned media (CM) from human colon adenocarcinoma (SW480) and from non-small-cell lung carcinoma (H1299) cultured cells. The cancer-CM-induced extensive myotube degeneration, demonstrated by a significant reduction in mature myotube diameter, which progressed over the period studied. Myotube degeneration is a characteristic feature of cancer cachexia and w...
Prostaglandins & Other Lipid Mediators
Pharmacology & Therapeutics
Cannabis and Cannabinoid Research
Background: Pharmacological management of chronic neuropathic pain (CNP) still represents a major... more Background: Pharmacological management of chronic neuropathic pain (CNP) still represents a major clinical challenge. Collective harnessing of both the scientific evidence base and clinical experience (of clinicians and patients) can play a key role in informing treatment pathways and contribute to the debate on specific treatments (e.g., cannabinoids). A group of expert clinicians (pain specialists and psychiatrists), scientists, and patient representatives convened to assess the relative benefit-safety balance of 12 pharmacological treatments, including orally administered cannabinoids/cannabis-based medicinal products, for the treatment of CNP in adults. Methods: A decision conference provided the process of creating a multicriteria decision analysis (MCDA) model, in which the group collectively scored the drugs on 17 effect criteria relevant to benefits and safety and then weighted the criteria for their clinical relevance. Findings: Cannabis-based medicinal products consisting of tetrahydrocannabinol/cannabidiol (THC/CBD), in a 1:1 ratio, achieved the highest overall score, 79 (out of 100), followed by CBD dominant at 75, then THC dominant at 72. Duloxetine and the gabapentinoids scored in the 60s, amitriptyline, tramadol, and ibuprofen in the 50s, methadone and oxycodone in the 40s, and morphine and fentanyl in the 30s. Sensitivity analyses showed that even if the pain reduction and quality-of-life scores for THC/CBD and THC are halved, their benefit-safety balances remain better than those of the noncannabinoid drugs. Interpretation: The benefit-safety profiles for cannabinoids were higher than for other commonly used medications for CNP largely because they contribute more to quality of life and have a more favorable side effect profile. The results also reflect the shortcomings of alternative pharmacological treatments with respect to safety and mitigation of neuropathic pain symptoms. Further high-quality clinical trials and systematic comprehensive
Wellcome Open Research, 2021
Background: Animal models of stroke have been criticised as having poor predictive validity, lack... more Background: Animal models of stroke have been criticised as having poor predictive validity, lacking risk factors prevalent in an aging population. This pilot study examined the development of comorbidities in a combined aged and high-fat diet model, and then examined the feasibility of modelling stroke in such rats. Methods: Twelve-month old male Wistar-Han rats (n=15) were fed a 60% fat diet for 8 months during which monthly serial blood samples were taken to assess the development of metabolic syndrome and pro-inflammatory markers. Following this, to pilot the suitability of these rats for undergoing surgical models of stroke, they underwent 30min of middle cerebral artery occlusion (MCAO) alongside younger controls fed a standard diet (n=10). Survival, weight and functional outcome were monitored, and blood vessels and tissues collected for analysis. Results: A high fat diet in aged rats led to substantial obesity. These rats did not develop type 2 diabetes or hypertension. Ther...
European Journal of Neurology, 2020
Background and purposeRemote ischaemic per‐conditioning (RIC) is neuroprotective in experimental ... more Background and purposeRemote ischaemic per‐conditioning (RIC) is neuroprotective in experimental ischaemic stroke. Several neurohumoral, vascular and inflammatory mediators are implicated. The effect of RIC on plasma biomarkers was assessed using clinical data from the REmote ischaemic Conditioning After Stroke Trial (RECAST‐1).MethodsRECAST‐1 was a pilot sham‐controlled blinded trial in 26 patients with ischaemic stroke, randomized to receive four 5‐min cycles of RIC within 24 h of ictus. Plasma taken pre‐intervention, immediately post‐intervention and on day 4 was analysed for nitric oxide (nitrate/nitrite) using chemiluminescence and all other biomarkers by multiplex analysis. Biomarkers were correlated with clinical outcome (day 90 National Institutes of Health Stroke Scale, modified Rankin Scale, Barthel index).ResultsRemote ischaemic per‐conditioning reduced serum amyloid protein (SAP) and tissue necrosis factor α (TNF‐α) levels from pre‐ to post‐intervention (n = 13, two‐way ...
Cannabis and Cannabinoid Research, 2021
Background and Objectives: Preclinical studies have shown cannabidiol is protective in models of ... more Background and Objectives: Preclinical studies have shown cannabidiol is protective in models of ischemic stroke. Based on results from our recent systematic review, we investigated the effects of two promising neuroprotective phytocannabinoids, cannabigerol (CBG) and cannabidivarin (CBDV), on cells of the blood-brain barrier (BBB), namely human brain microvascular endothelial cells (HBMECs), pericytes, and astrocytes. Experimental Approach: Cultures were subjected to oxygen-glucose deprivation (OGD) protocol to model ischemic stroke and cell culture medium was assessed for cytokines and adhesion molecules post-OGD. Astrocyte cell lysates were also analyzed for DNA damage markers. Antagonist studies were conducted where appropriate to study receptor mechanisms. Results: In astrocytes CBG and CBDV attenuated levels of interleukin-6 (IL-6) and lactate dehydrogenase (LDH), whereas CBDV (10 nM-10 lM) also decreased vascular endothelial growth factor (VEGF) secretion. CBDV (300 nM-10 lM) attenuated levels of monocyte chemoattractant protein (MCP)-1 in HBMECs. In astrocytes, CBG decreased levels of DNA damage proteins, including p53, whereas CBDV increased levels of DNA damage markers. Antagonists for CB 1 , CB 2 , PPAR-c, PPAR-a, 5-HT1 A , and TRPV1 had no effect on CBG (3 lM) or CBDV (1 lM)-mediated decreases in LDH in astrocytes. GPR55 and GPR18 were partially implicated in the effects of CBDV, but no molecular target was identified for CBG. Conclusions: We show that CBG and CBDV were protective against OG mediated injury in three different cells that constitute the BBB, modulating different hallmarks of ischemic stroke pathophysiology. These data enhance our understanding of the protective effects of CBG and CBDV and warrant further investigation into these compounds in ischemic stroke. Future studies should identify other possible neuroprotective effects of CBG and CBDV and their corresponding mechanisms of action.
Medical Cannabis and Cannabinoids, 2021
Introduction: Cannabidiol (CBD) can be isolated from Cannabis sativa L. or synthetically produced... more Introduction: Cannabidiol (CBD) can be isolated from Cannabis sativa L. or synthetically produced. The aim of this study was to compare the in vitro effects of purified natural and synthetic CBD to establish any pharmacological differences or superiority between sources. Methods: Six purified samples of CBD were obtained, 4 of these were natural and 2 synthetic. The anticancer effects of CBD were assessed in a human ovarian cancer cell line (SKOV-3 cells). The neuroprotective effects of CBD were assessed in human pericytes in a model of stroke (oxygen glucose deprivation [OGD]). The ability of CBD to restore inflammation-induced intestinal permeability was assessed in differentiated human Caco-2 cells (a model of enterocytes). Results: (1) In proliferating and confluent SKOV-3 cells, all CBD samples similarly reduced resazurin metabolism as a marker of cell viability in a concentration-dependent manner (p < 0.001). (2) In pericytes exposed to OGD, all CBD samples similarly reduce...
British Journal of Pharmacology, 2020
Embase and PubMed were systematically searched for articles addressing the neuroprotective proper... more Embase and PubMed were systematically searched for articles addressing the neuroprotective properties of phytocannabinoids, apart from cannabidiol and Δ9‐tetrahydrocannabinol, including Δ9‐tetrahydrocannabinolic acid, Δ9‐tetrahydrocannabivarin, cannabidiolic acid, cannabidivarin, cannabichromene, cannabichromenic acid, cannabichromevarin, cannabigerol, cannabigerolic acid, cannabigerivarin, cannabigerovarinic acid, cannabichromevarinic acid, cannabidivarinic acid, and cannabinol. Out of 2,341 studies, 31 articles met inclusion criteria. Cannabigerol (range 5 to 20 mg·kg−1) and cannabidivarin (range 0.2 to 400 mg·kg−1) displayed efficacy in models of Huntington's disease and epilepsy. Cannabichromene (10–75 mg·kg−1), Δ9‐tetrahydrocannabinolic acid (20 mg·kg−1), and tetrahydrocannabivarin (range 0.025–2.5 mg·kg−1) showed promise in models of seizure and hypomobility, Huntington's and Parkinson's disease. Limited mechanistic data showed cannabigerol, its derivatives VCE.003...
Neuro-Oncology, 2020
Paediatric brain tumours are the second most common cancer after haematological malignancies. Int... more Paediatric brain tumours are the second most common cancer after haematological malignancies. Intermittent dosing regimens are typical for chemotherapy drugs in order to avoid excessive damage to organs and avoid the onset of late effects. Cannabidiol (CBD) has been shown to have cytotoxic properties on paediatric brain tumour cell lines. Although CBD is far less toxic and damaging than the classical chemotherapy options which are currently available to children suffering with brain tumours, there are some possible side effects. Given that the half-life of the drug is 24 hours, it was important to establish the nature of the effect of cumulative dosing on top of the remaining drug in the system. The pHGG cell line, SF188 was cultured in different concentrations of CBD with either 1, 2 or 3 doses being given on consecutive days. 24 hours after the last dose the cells were analysed using the resazurin assay. It was observed that the amount of drug required for an EC50 to be obtained d...
Neuro-Oncology, 2020
Brain tumours are the leading cause of cancer related death in children with limited treatment op... more Brain tumours are the leading cause of cancer related death in children with limited treatment options and high recurrence rates. Recent evidence suggests there may be anti-tumoral properties of cannabinoids, and of cannabidiol (CBD) in particular. We evaluated the effect of CBD on paediatric brain tumour cell lines in 2D and 3D spheroids; pHGG (SF188), ependymoma (BxD-1425EPN) and human astrocytes. At the CBD EC50 concentration, astrocytic cell death was insignificant. 3D spheroids decreased in size by approximately 20% when cultured in CBD compared to cells only after 5-day exposure. Cell death increased with time after a single dose of CBD. Western Blot showed an increase in Lc3b expression (autophagy) after 24 hours incubation (early cell death) with CBD in both BxD-1425EPN and SF188 with PARP expression (apoptosis) increased after 5 days incubation (late cell death). Cell cycle analysis showed a decrease of cells in G1 and no change in G2 indicating cell cycle arrest. In hypoxi...
Frontiers in Endocrinology, 2020
Osteocalcin (OCN) is a bone-derived protein that is detected within human calcified vascular tiss... more Osteocalcin (OCN) is a bone-derived protein that is detected within human calcified vascular tissue. Calcification is particularly prevalent in chronic kidney disease (CKD) patients but the role of OCN in calcification, whether active or passive, has not been elucidated. Part 1: The relationship between OCN, CKD and vascular calcification was assessed in CKD patients (n = 28) and age-matched controls (n = 19). Part 2: in vitro, we analyzed whether addition of uncarboxylated osteocalcin (ucOCN) influenced the rate or extent of vascular smooth muscle cell (VSMC) calcification. Human aortic VSMCs were cultured in control media or mineralisation inducing media (MM) containing increased phosphate with or without ucOCN (10 or 30 ng/mL) for up to 21 days. Markers of osteogenic differentiation and calcification were determined [alkaline phosphatase (ALP) activity, total intracellular OCN, Runx2 expression, α-SMA expression, alizarin red calcium staining, and calcium quantification]. Part 1 results: In our human population, calcification was present (mean age 76 years), but no differences were detected between CKD patients and controls. Plasma total OCN was increased in CKD patients compared to controls (14 vs. 9 ng/mL; p < 0.05) and correlated to estimated glomerular filtration rate (p < 0.05), however no relationship was detected between total OCN and calcification. Part 2 results: in vitro, ALP activity, α-SMA expression and calcium concentrations were significantly increased in MM treated VSMCs at day 21, but no effect of ucOCN was observed. Cells treated with control media+ucOCN for 21 days did not show increases in ALP activity nor calcification. In summary, although plasma total OCN was increased in CKD patients, this study did not find a relationship between OCN and calcification in CKD and non-CKD patients, and found no in vitro evidence of an active role of ucOCN in vascular calcification as assessed over 21 days. ucOCN appears not to be a mediator of vascular calcification, but further investigation is warranted.
COVID-19-related anxiety and post-traumatic stress symptoms (PTSS) or disorder (PTSD) are likely ... more COVID-19-related anxiety and post-traumatic stress symptoms (PTSS) or disorder (PTSD) are likely to be a significant longterm issue emerging from the current pandemic. We hypothesise that cannabidiol (CBD), a chemical isolated from Cannabis Sativa with reported anxiolytic properties, could be a therapeutic option for the treatment of COVID-19-related anxiety disorders. In the global over-the-counter CBD market, anxiety, stress, depression and sleep disorders are consistently the top reasons people use CBD. In small randomised, controlled clinical trials, CBD reduces anxiety in healthy volunteers, patients with social anxiety disorder, those at clinical high risk of psychosis, in patients with Parkinson's disease, and in individuals with heroin use disorder. Case reports and series support these findings, extending to patients with anxiety and sleep disorders, Crohn's disease, depression and in PTSD. Preclinical studies reveal the molecular targets of CBD in these indications as the cannabinoid receptors type 1 and 2 (CB1 and CB2) receptors (mainly in fear memory processing), serotonin 5HT1a receptors (mainly in anxiolysis) and peroxisome proliferator-activated receptor gamma (PPARγ) (mainly in the underpinning anti-inflammatory/anti-oxidant effects). Observational and preclinical data also support CBD's therapeutic value in improving sleep (increased sleep duration/quality and reduction in nightmares) and depression, often comorbid with anxiety. Together these features of CBD to reduce anxiety and depression, and improve sleep disturbances, could be an attractive novel therapeutic option in relieving COVID-related post-traumatic stress symptoms.
Basic Science, 2019
beating hESC-derived cardiomyocytes and we propose to generate hESC-derived phenotypic models by ... more beating hESC-derived cardiomyocytes and we propose to generate hESC-derived phenotypic models by introducing selected apelin receptor mutations via CRISPR/Cas-9 gene editing.
Journal of Cellular Physiology, 2019
Some human observational studies have suggested an anti‐inflammatory role of osteocalcin (OCN). A... more Some human observational studies have suggested an anti‐inflammatory role of osteocalcin (OCN). An inflammatory protocol using interferon‐γ and tumor necrosis factor‐α (10 ng/ml) was employed to examine the acute (24 hr) and chronic (144 hr) effects of uncarboxylated OCN (ucOCN) in commercial, primary, subcultured human aortic endothelial cells (HAEC), and human smooth muscle cells (HASMCs). The inflammatory protocol increased phosphorylation of intracellular signaling proteins (CREB, JNK, p38, ERK, AKT, STAT3, STAT5) and increased secretion of adhesion markers (vascular cell adhesion molecule‐1, intracellular adhesion molecule‐1, monocyte chemoattractant protein‐1) and proinflammatory cytokines (interleukin‐6 [IL‐6], IL‐8). After acute inflammation, there were no additive or reductive effects of ucOCN in either cell type. Following chronic inflammation, ucOCN did not affect cell responses, nor did it appear to have any pro‐ or anti‐inflammatory effects when administered acutely or ...
PeerJ, 2019
Bone-derived factors that demonstrate extra-skeletal functions, also termed osteokines, are fast ... more Bone-derived factors that demonstrate extra-skeletal functions, also termed osteokines, are fast becoming a highly interesting and focused area of cross-disciplinary endocrine research. Osteocalcin (OCN), fibroblast growth factor-23 (FGF23) and lipocalin-2 (LCN-2), produced in bone, comprise an important endocrine system that is finely tuned with other organs to ensure homeostatic balance and health. This review aims to evaluatein vitroevidence of the direct involvement of these proteins in vascular cells and whether any causal roles in cardiovascular disease or inflammation can be supported. PubMed, Medline, Embase and Google Scholar were searched for relevant research articles investigating the exogenous addition of OCN, FGF23 or LCN-2 to vascular smooth muscle or endothelial cells. Overall, these osteokines are directly vasoactive across a range of human and animal vascular cells. Both OCN and FGF23 have anti-apoptotic properties and increase eNOS phosphorylation and nitric oxide...
British Journal of Clinical Pharmacology, 2019
AimsCannabidiol (CBD) is a cannabis‐derived medicinal product with potential application in a wid... more AimsCannabidiol (CBD) is a cannabis‐derived medicinal product with potential application in a wide‐variety of contexts; however, its effective dose in different disease states remains unclear. This review aimed to investigate what doses have been applied in clinical populations, in order to understand the active range of CBD in a variety of medical contexts.MethodsPublications involving administration of CBD alone were collected by searching PubMed, EMBASE and ClinicalTrials.gov.ResultsA total of 1038 articles were retrieved, of which 35 studies met inclusion criteria covering 13 medical contexts. Twenty‐three studies reported a significant improvement in primary outcomes (e.g. psychotic symptoms, anxiety, seizures), with doses ranging between <1 and 50 mg/kg/d. Plasma concentrations were not provided in any publication. CBD was reported as well tolerated and epilepsy was the most frequently studied medical condition, with all 11 studies demonstrating positive effects of CBD on r...
Frontiers in Cellular Neuroscience, 2019
Structural alterations and breakdown of the blood brain barrier (BBB) is often a primary or secon... more Structural alterations and breakdown of the blood brain barrier (BBB) is often a primary or secondary consequence of disease, resulting in brain oedema and the transport of unwanted substances into the brain. It is critical that effective in vitro models are developed to model the in vivo environment to aid in clinically relevant research, especially regarding drug screening and permeability studies. Our novel model uses only primary human cells and includes four of the key cells of the BBB: astrocytes, pericytes, brain microvascular endothelial cells (HBMEC) and neurons. We show that using a larger membrane pore size (3.0 µM) there is an improved connection between the endothelial cells, astrocytes and pericytes. Compared to a two and three cell model, we show that when neurons are added to HBMECs, astrocytes and pericytes, BBB integrity was more sensitive to oxygen-glucose deprivation evidenced by increased permeability and markers of cell damage. Our data also show that a four cell model responds faster to the barrier tightening effects of glucocorticoid dexamethasone, when compared to a two cell and three cell model. These data highlight the important role that neurons play in response to ischaemia, particularly how they contribute to BBB maintenance and breakdown. We consider that this model is more representative of the interactions at the neurovascular unit than other transwell models and is a useful method to study BBB physiology.
Journal of Cellular Physiology, 2019
The purpose of this study was to characterize the direct effects of uncarboxylated osteocalcin (u... more The purpose of this study was to characterize the direct effects of uncarboxylated osteocalcin (ucOCN) on vascular cell biology in vitro, to assess its potential function in pathophysiological conditions such as atherosclerosis. Human aortic endothelial cells (HAECs) and smooth muscle cells (HASMCs) were treated with ucOCN (0.1–50 ng/ml) and changes in phosphorylation of intracellular signaling proteins, angiogenesis, proliferation, migration, monolayer permeability, and protein secretion were measured. In HAECs, phosphorylated JNK and CREB were decreased with ucOCN (p < 0.05). In HASMCs, phosphorylated p70S6K and NF‐ΚB were increased by ucOCN (p < 0.05). Cell proliferation increased in both cell types dose dependently which was blocked by AKT and ERK pathway inhibitors. ucOCN did not affect cell permeability, angiogenesis, or migration. The direct activity of ucOCN on vascular cells is recognized, particularly its proliferative effects. However, at least in physiological sett...
Inflammatory Bowel Diseases, 2019
Background and aims: We aimed to examine, for the first time, the effect of cannabidiol (CBD) and... more Background and aims: We aimed to examine, for the first time, the effect of cannabidiol (CBD) and palmitoylethanolamide (PEA) on the permeability of the human gastrointestinal tract in vitro, ex vivo, and in vivo. Methods: Flux measurements of fluorescein-labeled dextrans 10 (FD10) and fluorescein-labeled dextrans 4 (FD4) dextran across Caco-2 cultures treated for 24 hours with interferon gamma (IFNγ) and tumour necrosis factor alpha (TNFα) (10 ng•mL −1) were measured, with or without the presence of CBD and PEA. Mechanisms were investigated using cannabinoid receptor 1 (CB 1), cannabinoid receptor 2 (CB 2), transient receptor potential vanilloid 1 (TRPV1), and proliferator activated receptors (PPAR) antagonists and protein kinase A (PKA), nitric oxide synthase, phosphoinositide 3-kinases, extracellular signal-regulated kinases (MEK/ERK), adenylyl cyclase, and protein kinase C (PKC) inhibitors. Human colonic mucosal samples collected from bowel resections were treated as previously stated. The receptors TRPV1, PPARα, PPARδ, PPARγ, CB 1 , CB 2 , G-coupled protein receptor 55 (GPR55), G-coupled protein receptor 119 (GPR119), and claudins-1,-2,-3,-4,-5,-7, and-8 mRNA were measured using multiplex. Aquaporin 3 and 4 were measured using enzyme-linked immunosorbent assay (ELISA). A randomized, double-blind, controlled-trial assessed the effect of PEA or CBD on the absorption of lactulose and mannitol in humans taking 600 mg of aspirin. Urinary concentrations of these sugars were measured using liquid chromatography mass spectrometry. Results: In vitro, PEA, and CBD decreased the inflammation-induced flux of dextrans (P < 0.0001), sensitive to PPARα and CB 1 antagonism, respectively. Both PEA and CBD were prevented by PKA, MEK/ERK, and adenylyl cyclase inhibition (P < 0.001). In human mucosa, inflammation decreased claudin-5 mRNA, which was prevented by CBD (P < 0.05). Palmitoylethanolamide and cannabidiol prevented an inflammation-induced fall in TRPV1 and increase in PPARα transcription (P < 0.0001). In vivo, aspirin caused an increase in the absorption of lactulose and mannitol, which were reduced by PEA or CBD (P < 0.001). Conclusion: Cannabidiol and palmitoylethanolamide reduce permeability in the human colon. These findings have implications in disorders associated with increased gut permeability, such as inflammatory bowel disease.
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Papers by Saoirse O'Sullivan