Nanoformulations as a strategy to overcome the delivery limitations of cannabinoids

Medical cannabis has received significant interest in recent years due to its promising benefits in the management of pain, anxiety, depression and neurological and movement disorders. Specifically, the major phytocannabinoids derived from the cannabis plant such as (-) trans-Δ⁹ -tetrahydrocannabinol (THC) and cannabidiol (CBD), have been shown to be responsible for the pharmacological and therapeutic properties. Recently, these phytocannabinoids have also attracted special attention in cancer treatment due to their well-known palliative benefits in chemotherapy-induced nausea, vomiting, pain and loss of appetite along with their anticancer activities. Despite the enormous pharmacological benefits, the low aqueous solubility, high instability (susceptibility to extensive first pass metabolism) and poor systemic bioavailability restrict their utilization at clinical perspective. Therefore, drug delivery strategies based on nanotechnology are emerging to improve pharmacokinetic profile and bioavailability of cannabinoids as well as enhance their targeted delivery. Here, we critically review the nano-formulation systems engineered for overcoming the delivery limitations of native phytocannabinoids including polymeric and lipid-based nanoparticles (lipid nano capsules (LNCs), nanostructured lipid carriers (NLCs), nanoemulsions (NE) and self-emulsifying drug delivery systems (SEDDS)), ethosomes and cyclodextrins as well as their therapeutic applications.

Negotiating Ambiguous Substance Use: UK newspaper representations of self-prescribing medicinal cannabis use in the 1990s

This paper examined representations of medicinal cannabis users in UK newspapers, 1990–1998. It is important to understand the significance of these newspaper articles during this early stage of the growing cultural normalisation of medicinal cannabis use, in the UK, which is not documented in the existing literature. This is a very different period in relation to access to information for members of the public because it was before the widespread use of the internet. The significance of these dates is also that I started interviewing medicinal cannabis users in 1998, which led to Coomber et al. (2003). Very significantly, almost half of the participants in that article indicated that newspapers were the source of the idea that cannabis was medicinally useful and that this accounted for why they began to use it medicinally. What was in those newspaper articles that encouraged this view? In the current article, I examined 60 newspaper articles about medicinal cannabis use, using a thematic analysis which also draws on aspects of critical discourse analysis. I report on the process of symbolic boundary work which negotiates the ambiguity of individuals portrayed as social insiders but who used cannabis. The representations within the articles emphasized the social insider characteristics of medicinal cannabis users, emphasized their genuine illnesses/impairments, but interestingly also articulated misunderstandings by the journalists which contributed to a positive portrayal.

‘You can’t stand on a corner and talk about it …’: Medicinal cannabis use, impression management and the analytical status of interviews

In this article, I examine how four medicinal cannabis users used impression management during in-depth, qualitative interviews to attend to self-presentational concerns. I examine the rhetorical strategies and narratives articulated by the participants while also attending to the role that I played in co-construction as the interviewer. Later I discuss how, although the participants’ accounts are occasioned by the interviews, they can still provide significant insights into the social worlds of the participants beyond the interviews. While discussions about whether to treat interviews as topic, resource or both are not new, I argue that we can treat interviews as both topic and resource because impression management is a product of the individual’s habitus and it and the accounts it produces are part of their social world.

Cannabis and epilepsy: An ancient treatment returns to the fore

Cannabis has been associated with the treatment of epilepsy throughout history, and if ancient Assyrian sources referring to "hand of ghost" are considered credible, this relationship may span four millennia. A tradition of usage continued in Arabic medicine and Ayurvedic practice in India, which led, in turn, to early experiments in Europe and North America with "Indian hemp." Lack of standardization, bioavailability issues, and ultimately prohibition were all factors in cannabis-based medicines failing to maintain mainstream usage in seizure treatment, but investigation was resumed in the 1970s with interesting signals noted in both laboratory and clinical settings. Early case studies showed promise, but lacked sufficient rigor. Resumption of research coupled with mass experimentation by families of epilepsy patients has led to intense interest in cannabis-based medicines for its treatment once more, with greatest focus on cannabidiol, but additional investigation of tetrahydrocannabinol, tetrahydrocannabinolic acid, and other phytocannabinoids. This article is part of a Special Issue entitled "Cannabinoids and Epilepsy".

Cannabinoids in eating disorders and obesity

Cannabinoid system is a crucial mechanism in regulating food intake and energy metabolism. It is involved in central and peripheral mechanisms regulating such behavior, interacting with many other signaling systems with a role in metabolic regulation. Cannabinoid agonists promote food intake, and soon a cannabinoid antagonist, rimonabant, will be marketed for the treatment of obesity. It not only causes weight loss, but also alleviates metabolic syndrome. We present a review of current knowledge on this subject, along with data from our own research: genetic studies on this system in eating disorders and obesity and studies locating cannabinoid receptors in areas related to food intake. Such studies suggest cannabinoid hyperactivity in obesity, and this excessive activity may have prognostic implications.

Cannabinoids induce cancer cell proliferation via tumor necrosis factor alpha-converting enzyme (TACE/ADAM17)-mediated transactivation of the epidermal growth factor receptor

Cannabinoids, the active components of marijuana and their endogenous counterparts were reported as useful analgetic agents to accompany primary cancer treatment by preventing nausea, vomiting, and pain and by stimulating appetite. Moreover, they have been shown to inhibit cell growth and to induce apoptosis in tumor cells. Here, we demonstrate that anandamide, Delta(9)-tetrahydrocannabinol (THC), HU-210, and Win55,212-2 promote mitogenic kinase signaling in cancer cells. Treatment of the glioblastoma cell line U373-MG and the lung carcinoma cell line NCI-H292 with nanomolar concentrations of THC led to accelerated cell proliferation that was completely dependent on metalloprotease and epidermal growth factor receptor (EGFR) activity. EGFR signal transactivation was identified as the mechanistic link between cannabinoid receptors and the activation of the mitogen-activated protein kinases extracellular signal-regulated kinase 1/2 as well as prosurvival protein kinase B (Akt/PKB) signaling. Depending on the cellular context, signal cross-communication was mediated by shedding of proAmphiregulin (proAR) and/or proHeparin-binding epidermal growth factor-like growth factor (proHB-EGF) by tumor necrosis factor alpha converting enzyme (TACE/ADAM17). Taken together, our data show that concentrations of THC comparable with those detected in the serum of patients after THC administration accelerate proliferation of cancer cells instead of apoptosis and thereby contribute to cancer progression in patients.

Patterns of marijuana use among patients with HIV/AIDS followed in a public health care setting

OBJECTIVES

To examine prevalence and patterns of smoked marijuana and perceived benefit and to assess demographic and clinical factors associated with marijuana use among HIV patients in a public health care setting.

METHODS

Participants (n = 252) were recruited via consecutive sampling in public health care clinics. Structured interviews assessed patterns of recent marijuana use, including its perceived benefit for symptom relief. Associations between marijuana use and demographic and clinical variables were examined using univariate and multivariate regression analyses.

RESULTS

Overall prevalence of smoked marijuana in the previous month was 23%. Reported benefits included relief of anxiety and/or depression (57%), improved appetite (53%), increased pleasure (33%), and relief of pain (28%). Recent use of marijuana was positively associated with severe nausea (odds ratio [OR] = 4.0, P = 0.004) and recent use of alcohol (OR = 7.5, P < 0.001) and negatively associated with being Latino (OR = 0.07, P < 0.001). No associations between marijuana use and pain symptoms were observed.

CONCLUSIONS

The findings suggest that providers be advised to assess routinely and better understand patients' "indications" for self-administration of cannabis. Given the estimated prevalence, more formal characterization of the patterns and impact of cannabis use to alleviate HIV-associated symptoms is warranted. Clinical trials of smoked and noncombustible marijuana are needed to determine the role of cannabinoids as a class of agents with potential to improve quality of life and health care outcomes among patients with HIV/AIDS.