Current Pharmaceutical Design - Volume 22, Issue 42, 2016

Background: Globally, the most widely used set of compounds among the internationally regulated drugs is cannabis. Objective: To review evidence from epidemiological research on cannabis, organized in relation to this field's five main rubrics: quantity, location, causes, mechanisms, and prevention/ control. Method: The review covers a selection of evidence from standardized population surveys, official statistics, and governmental reports, as well as published articles and books identified via MEDLINE, Web of Science, and Google Scholar as of July 2016. Results: In relation to quantity, an estimated 3% to 5% of the world population is thought to have tried a cannabis product, with at least one fairly recent use, mainly extra-medical and outside boundaries of prescribed use. Among cannabis users in the United States, roughly one in 7-8 has engaged in medical marijuana use. In relation to location, prevalence proportions reveal important variations across countries and between subgroups within countries. Regarding causes and mechanisms of starting to use cannabis, there is no compelling integrative and replicable conceptual model or theoretical formulation. Most studies of mechanisms have focused upon a ‘gateway sequence’ and person-to-person diffusion, with some recent work on disability-adjusted life years. A brief review of cannabis use consequences, as well as prevention and control strategies is also provided. Conclusion: At present, we know much about the frequency and occurrence of cannabis use, with too little replicable definitive evidence with respect to the other main rubrics. Given a changing regulatory environment for cannabis products, new institutions such as an independent International Cannabis Products Safety Commission may be required to produce evidence required to weigh benefits versus costs. It is not clear that governmentsponsored research will be sufficient to meet consumer demand for balanced points of view and truly definitive evidence.

Background: Cannabis use typically commences during adolescence, a period during which the brain undergoes profound remodeling in areas that are high in cannabinoid receptors and that mediate cognitive control and emotion regulation. It is therefore important to determine the impact of adolescent cannabis use on brain function. Objective: We investigate the impact of adolescent cannabis use on brain function by reviewing the functional magnetic resonance imaging studies in adolescent samples. Method: We systematically reviewed the literature and identified 13 functional neuroimaging studies in adolescent cannabis users (aged 13 to 18 years) performing working memory, inhibition and reward processing tasks. Results: The majority of the studies found altered brain function, but intact behavioural task performance in adolescent cannabis users versus controls. The most consistently reported differences were in the frontal-parietal network, which mediates cognitive control. Heavier use was associated with abnormal brain function in most samples. A minority of studies controlled for the influence of confounders that can also undermine brain function, such as tobacco and alcohol use, psychopathology symptoms, family history of psychiatric disorders and substance use. Conclusion: Emerging evidence shows abnormal frontal-parietal network activity in adolescent cannabis users, particularly in heavier users. Brain functional alterations may reflect a compensatory neural mechanism that enables normal behavioural performance. It remains unclear if cannabis exposure drives these alterations, as substance use and mental health confounders have not been systematically examined.

Cannabis is the most widely used illicit drug worldwide. Regular cannabis use has been associated with a range of acute and chronic mental health problems, such as anxiety, depression, psychotic symptoms and neurocognitive impairments and their neural mechanisms need to be examined. This review summarizes and critically evaluates brain-imaging studies of cannabis in recreational and regular cannabis users between January 2000 and January 2016. The search has yielded eligible 103 structural and functional studies. Regular use of cannabis results in volumetric, gray matter and white matter structural changes in the brain, in particular in the hippocampus and the amygdala. Regular use of cannabis affects cognitive processes such as attention, memory, inhibitory control, decision-making, emotional processing, social cognition and their associated brain areas. There is evidence that regular cannabis use leads to altered neural function during attention and working memory and that recruitment of activity in additional brain regions can compensate for it. Similar to other drugs of abuse, cannabis cues activated areas in the reward pathway. Pharmacological studies showed a modest increase in human striatal dopamine transmission after administration of THC in healthy volunteers. Regular cannabis use resulted in reduced dopamine transporter occupancy and reduced dopamine synthesis but not in reduced striatal D2/D3 receptor occupancy compared with healthy control participants. Studies also showed different effects of Δ-9 tetrahydrocannabinol (THC) and cannabidiol (CBD) on emotion, cognition and associated brain regions in healthy volunteers, whereby CBD protects against the psychoactive effects of THC. Brain imaging studies using selective high-affinity radioligands for the imaging of cannabinoid CB1 receptor availability in Positron Emission Tomography (PET) showed downregulation of CB1 in regular users of cannabis. In conclusion, regular use of the cannabinoids exerts structural and functional changes in the human brain. These changes have profound implications for our understanding of the neuropharmacology of cannabis and its effects on cognition, mental health and the brain.

There is growing interest in the relationship between cannabis and psychosis. The link between cannabis use and psychosis comprises three distinct relationships: acute psychosis associated with cannabis intoxication, acute psychosis that lasts beyond the period of acute intoxication, and persistent psychosis not time-locked to exposure. Experimental studies reveal that cannabis, tetrahydrocannabinol (THC) and synthetic cannabinoids reliably produce transient positive, negative, and cognitive symptoms in healthy volunteers. Case-studies indicate that cannabinoids can induce acute psychosis which lasts beyond the period of acute intoxication and persisting as long as a month. Exposure to cannabis in adolescence is associated with an increased risk for later psychotic disorder in adulthood; this association is consistent, somewhat specific, shows a dose-response, and is biologically plausible. The link between cannabinoids and psychosis is greater with earlier age of exposure to cannabinoids, childhood abuse and genetic vulnerability. However, cannabinoids are neither necessary nor sufficient to cause a persistent psychotic disorder. More likely cannabinoids are a ‘component cause’ interacting with other known (family history) and unknown factors to result in psychosis outcomes. While more research is needed to better understand the relationship between cannabinoid use and psychosis, and the neural underpinnings of this link, clinicians should be mindful of the potential risk of psychosis especially in vulnerable populations, including adolescents and those with a psychosis diathesis.

Cannabis consumption has radically changed over the last several decades. Tetrahydrcannbidiol concentrations are rising, cannabidiol concentrations falling and cannabis is becoming legalized in several regions of the globe. Concerns have been raised as to the impact of increased cannabis exposure within the general population on public health. One of the more serious concerns is the potential relationship between cannabis consumption and psychosis. Research has shown a relationship between increasing cannabis use and increasing psychosis risk. This risk is moderated by other factors such as stress and a family history of psychosis. Within this context, it is important to determine potential markers for future psychosis risk. Genetic and epigenetic research in cannabis and psychosis is in its early stages. One common denominator between cannabis use disorder and psychosis is dopamine dysfunction. Research has begun to link heightened dopamine reactivity with the psychotomimetic effects of cannabis. Studies in COMT and DRD2 polymorphisms have failed to show greater associations with transition to psychosis. Studies of AKT1 have shown slightly more promising results. Genome-wide association studies have recently been published some indicating novel polymorphisms. These may pave the way to alternate hypotheses to explain the missing links between cannabis use and increased risk of psychosis. Such knowledge may eventually lead to new pharmacotherapies in addition to the means of screening patients for psychosis risk.

Background: As policy responses to cannabis use and availability change internationally, levels of cannabis use disorder rise and treatment seeking increases. Diversion to cannabis treatment from the criminal justice system also increases demand in the system. At a time of developing treatment systems in response to this demand, an understanding of the evidence is increasingly important. Objective: To provide a narrative review of the developing evidence-base for psycho-social interventions for cannabis use disorder, including adjunctive cannabinoid agonist therapy. Method: Two researchers independently conducted a literature search for articles published prior to February 2016, located through online search of four electronic databases (Google Scholar, CINAHL, Medline, and PsycINFO). Only randomised controlled trials describing treatment(s) for cannabis use or cannabis use disorder with a measure of either cannabis use frequency or cannabis use disorder severity were included. Non-English papers, review papers, posters, opinion pieces, letters or editorials, case studies (N<10) and published abstracts were excluded. Results: The cannabis treatment most likely to be effective for adolescents and adults is based on the combination of Motivational Enhancement Therapy (MET) and Cognitive Behavioural Therapy (CBT) with the inclusion of contingency management and agonist replacement therapy showing promise. Conclusion: A more concrete and robust evidence base is required for these interventions. Replication of treatment studies is needed using standardised interventions, methods and measures to minimise conflicting findings, inconsistent follow-up periods and relatively poor treatment effects over time.(243 words)

Background: Cannabis is the most widely used illicit psychoactive substance world-wide, yet no medication is approved for the treatment of intoxication, withdrawal, or cannabis use disorder (CUD). Objective: To comprehensively review the current state of knowledge. Method: Search of the PubMed electronic data base and review of reference lists of relevant articles to identify controlled clinical trials of pharmacological treatment. Results: The search identified 4 trials for specific intoxication symptoms (none for global intoxication), 7 trials for withdrawal, and 12 phase II trials for CUD. One or two trials each suggest that propranolol is effective for some intoxication symptoms, antipsychotics for cannabis-induced psychosis, and dronabinol (synthetic THC) and gabapentin for cannabis withdrawal. Of 10 medications and one medication combination studied in 12 trials for CUD, only two medications were effective (in single trials): gabapentin and Nacetylcysteine (in adolescents). Not effective were dronabinol and several antidepressants, anticonvulsants, and antianxiety medications. Three trials of antidepressants for CUD with comorbid depression gave inconsistent results. A trial of atomoxetine for CUD with comorbid ADHD showed no efficacy. Five trials of second-generation antipsychotics for CUD with comorbid schizophrenia showed none better than any other. Conclusion: Further research is needed to confirm the efficacy of gabapentin for withdrawal and gabapentin and N-acetylcysteine for CUD and to develop new medications for all 3 cannabis-related disorders.

« Spice » is generally used to describe the diverse types of herbal blends that encompass synthetic cannabinoids on the market. The emergence of smokable herbal products containing synthetic cannabinoids, which mimic the effects of cannabis, appears to become increasingly popular, in the new psychoactive substances landscape. In 2014, the existence of 134 different types of synthetic cannabinoids were reported by the European Union Early Warning System. These drugs are mainly sold online as an alternative to controlled and regulated psychoactive substances. They appear to have a life cycle of about 1-2 years before being replaced by a next wave of products. Legislation controlling these designer drugs has been introduced in many countries with the objective to limit the spread of existing drugs and control potential new analogs. The majority of the synthetic cannabinoids are full agonists at the CB1 receptor and do not contain tobacco or cannabis. They are becoming increasingly popular in adolescents, students and clubbers as an abused substance. Relatively high incidence of adverse effects associated with synthetic cannabinoids use has been documented in the literature. Numerous fatalities linked with their use and abuse have been reported. In this paper, we will review the available data regarding the use and effects of synthetic cannabinoids in humans in order to highlight their impact on public health. To reach this objective, a literature search was performed on two representative databases (Pubmed, Google Scholar), the Erowid Center website (a US non-profit educational organization that provides information about psychoactive plants and chemicals), and various governmental websites. The terms used for the database search were: “synthetic cannabinoids”, “spice”, “new psychoactive substances”, and/or “substance use disorder”, and/or “adverse effects”, and/or “fatalities”. The search was limited to years 2005 to 2016 due to emerging scientific literature at this period Health professionals should take into account that limited scientific evidence is available regarding the effect of synthetic cannabinoids use in humans. It thus urges to launch more systematic epidemiological studies, to develop and validate screening procedures, and to investigate the neurobiological and psychological correlates and risk factors associated to synthetic cannabinoids use and misuse.

Background: Several antiepileptic drugs (AEDs), about 25, are currently clinically available for the treatment of patients with epilepsy. Despite this armamentarium and the many recently introduced AEDs, no major advances have been achieved considering the number of drug resistant patients, while many benefits have been indeed obtained for other clinical outcomes (e.g. better tolerability, less interactions). Cannabinoids have long been studied for their potential therapeutical use and more recently phytocannabinoids have been considered a valuable tool for the treatment of several neurological disorders including epilepsy. Among this wide class, the most studied is cannabidiol (CBD) considering its lack of psychotropic effects and its anticonvulsant properties. Objective: Analyse the currently available literature on CBD also in light of other data on phytocannabinoids, reviewing data spanning from the mechanism of action, pharmacokinetic to clinical evidences. Results: Several preclinical studies have tried to understand the mechanism of action of CBD, which still remains largely not understood. CBD has shown significant anticonvulsant effects mainly in acute animal models of seizures; beneficial effects were reported also in animal models of epileptogenesis and chronic models of epilepsy, although not substantial. In contrast, data coming from some studies raise questions on the effects of other cannabinoids and above all marijuana. Conclusion: There is indeed sufficient supporting data for clinical development and important antiepileptic effects and the currently ongoing clinical studies will permit the real usefulness of CBD and possibly other cannabinoids. Undoubtedly, several issues also need to be addressed in the next future (e.g. better pharmacokinetic profiling). Finally, shading light on the mechanism of action and the study of other cannabinoids might represent an advantage for future developments.

The regulatory paradigm is relaxing gradually without compromising the safety, efficacy and the quality of the drug product and, most importantly, a perceptible scientific consensus is maturing towards the need of affordable medicines. The establishment of bioequivalence (BE) is no longer being considered to be accomplished only by in vivo studies in oral drug products. The potential use of in vitro dissolution testing in lieu of BE studies has now been regulatory adopted and is commonly referred to as “biowaiver”. Further, the advent of biopharmaceutics classification system (BCS) and in vitro-in vivo correlation (IVIVC) proves to be sound milestones and signifies that we are incessantly forwarding towards a scenario that would reduce regulatory burden, save time and make the drug products more affordable while ensuring their quality. This review outlines, the current and pertinent regulatory environment for biowaiver based on in vitro drug dissolution, primarily as per the FDA perspective. The rationale used for qualification of biowaiver for different strengths, post-approval changes and multi-source products are discussed along with the role of BCS and IVIVC.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with a very poor prognosis, and excessive resistance to chemotherapy. MicroRNAs have been shown to play important roles in PDAC oncogenesis as they can act as both oncogenes and tumor suppressor molecules. Altered expression of specific microRNAs in PDAC has diagnostic and prognostic implications. There is growing body of evidence showing the important role of miR-486-5p and miR-938 for discrimination of PDAC patients from healthy subjects and those with chronic pancreatitis. Additionally the diagnostic features of miR-486-5p were comparable with CA 19-9 for the detection of PDAC patients, suggesting its diagnostic value as a blood-based miRNA in PDAC, although further investigations are warranted for validation of this marker. In addition to these applications, several studies have suggested therapeutic potential of some miRNAs in PDAC. In particular, modulations of let-7, miR-29a, miR-17-5p, miR-365, miR-181b, miR-21, miR-221 and miR-96 are reported to be associated with tumor response. Moreover, enforced expression of miR-17-92 inhibits tumourigenicity and increased chemoresistance in PDAC cancer stem cells via TGF-β1 pathway, while overexpression of miR-96 suppresses cell proliferation, migration, and invasion in a manner associated with KRAS downregulation. In this review we attempt to give an overview about recent preclinical and clinical studies that have addressed the potential use of circulating microRNAs as diagnostic and prognostic biomarkers, their use as therapeutic targets and finally, we discuss the possible role of microRNAs in PDAC chemoresistance.

Background: It is known that statins possess beneficial cardioprotective effects irrespective of lipidlowering action and that cardiac injury due ischemia/reperfusion is associated with Ca2+ dysregulation resulting in contractile dysfunction. Objective: With this background, we tested a hypothesis that simvastatin influences signaling of Ca2+/calmodulindependent protein kinase IIδ (CaMKIIδ), a protein kinase regulating both Ca2+ homeostasis and thick filament function, and thereby might underlie the mitigation of ischemia/reperfusion (I/R)-induced cardiac dysfunction. Method: Isolated hearts of control and simvastatin-treated (p.o. 10 mg/kg, 5 days) rats were subjected to global I and R and Western blotting was used to study the expression/activation of certain signaling proteins. Results: Simvastatin treatment did not modify the plasma lipid levels; however, it recovered depressed cardiac performance and reduced reperfusion arrhythmias without affecting the activation of CaMKIIδ through phosphorylation of Thr287. Activation of its downstreams, such as phospholamban (PLN) and cardiac myosin-binding protein C (cMyBP-C) at Thr17 and Ser282, respectively, was in accordance with the levels of pThr287-CaMKIIδ. Total expression of these proteins, however, did not follow the same pattern and was either unchanged (CaMKIIδ, cMYBP-C) or increased (PLN). Likewise, PLN/SERCA2a (sarco/endoplasmic reticulum Ca2+-ATPase 2a) ratio in I/R hearts was unaffected by the treatment. On the other hand, simvastatin reversed the increased protein expression of protein phosphatase 1β (PP1β), but not protein phosphatase 2A (PP2A), in I/R hearts. Conclusion: A lower rate of dephosphorylation and thereby a delay in inactivation of phosphorylated proteins due to a decrease in PP1β, rather than effects on phosphorylation of CaMKIIδ and its downstreams, such as PLN and cMyBP-C, may underlie beneficial effects of simvastatin in I/R hearts.

Background: Ischemic stroke is one of the leading causes of mortality and morbidity in the world and effective neuroprotectants are yet to be developed. Recent studies have demonstrated excellent neuroprotective effects of a bivalent enkephalin opioid agonist, biphalin in multiple stroke models. Methods: The purpose of this study is to evaluate novel multifunctional enkephalin-fentanyl opioid agonists, LYS436, LYS739 and LYS416 for their neuroprotective potential using in vitro and in vivo ischemic stroke models and to compare the effect to that of biphalin. Results: In general, all non-selective opioid agonists significantly decreased neuronal cell death and levels of reactive oxygen species in primary neurons subjescted to hypoxia-aglycemia/re-oxygenation or NMDA neurotoxicity. Fluorinated enkephalin-fentanyl conjugate, LYS739 showed enhanced neuroprotection in both in vitro models compared to biphalin. Based on further in vitro screening and comparative studies to biphalin, LYS739 was selected as a lead for in vivo experimentation. A mouse middle cerebral artery occlusion (MCAO) stroke model was utilized to study biphalin and the lead analog, LYS739. Both agonists significantly decreased brain infarct and edema ratios compared to saline treated group. Neurological impairment after stroke was statistically significantly improved in terms of neurological score and locomotor activities with LYS739 and biphalin treatment. Importantly, LYS739 and biphalin demonstrated better neuroprotection compared to fentanyl, and this effect was reversed by non-selective opioid antagonist naltrexone. Conclusion: In summary, the results of this study suggest that the multifunctional fluorinated enkephalin analog, LYS739 can be considered as a potential lead for ischemic stroke research and may provide advantages given the multimeric peptide-opiate structure.

Background: Prevalence of chronic diseases are on the rise with majority occurring in developing countries where the projected death caused by chronic diseases will reach 50 million by the year 2020. Objective: The aim of the study is to evaluate and compare the outcomes of wireless mobile device (Telemonitoring) with Pharmacist intervention and usual care on glycemic control and clinical outcomes. Method: This study is a six-month parallel groups interventional longitudinal multi-center study with a control arm. The study participants consist of patient diagnosed with type 2 diabetes mellitus and attending the outpatient department (OPD) for diabetic treatment. The study protocol is approved from ministry of health Malaysia and clinical research committee (CRC). Data analysis was made using IBM SPSS Statistics, version 22 (Armok, NY). Results: A total of 150 participants were selected to enroll in this study. Initial baseline comparison showed ‘No significant difference’ between the two intervention arms and control group. Findings showed that baseline dataset have no significant change among all three-arms. However last week of study showed significant (p<0.001) improvement among pharmacist intervention arm as compared to telemonitoring and control arm. Glycemic control seems well tolerated and managed among pharmacist intervention arm as compared to telemonitoring and control arm (p<0.001). The study findings also showed reduction of mean 2.72 % (HbA1c) as compare to baseline in six months. The proportion of participants experiencing hypoglycemic/hyperglycemic events was significantly lower in the pharmacist intervention group compared to telemonitoring and control arm (odds ratio: 2.1381; 95% CI: 3.0267-1.6059, p<0.001). Conclusion: The Pharmacist educational focus-home care program improves the patient knowledge, self-care practices and also significantly reduce the adverse events over study duration.