Delta-9-tetrahydrocannabinol increases vascular endothelial growth factor (VEGF) secretion through a cyclooxygenase-dependent mechanism in rat granulosa cells

DNA methylation, but not microRNA expression, is affected by in vitro THC exposure in bovine granulosa cells

BACKGROUND

A global increase in cannabis use has led to questions about its effects on fertility. The rise in consumption amongst women of reproductive age is a growing concern, as this group is vulnerable in terms of reproductive health. Ample evidence suggests that the psychoactive component of cannabis, Δ9-Tetrahydrocannabinol (THC), interacts with the endocannabinoid system (ECS), that helps regulate mammalian reproduction. This study aimed to research the epigenetic effects of THC in bovine granulosa cells (GCs) by (1) investigating global DNA methylation via measuring 5-mC and 5-hmC levels; (2) measuring key methylation regulators, including the methylating enzymes DNMT1, DNMT3a, DNMT3b and the demethylases TDG and TET1/2/3; and (3) assessing fertility-associated miRNAs key in developmental competency, including miR-21, -155, -33b, -324 and -346.

METHODS

Bovine GCs were used as a translational model for reproductive toxicity in humans. To determine THC effects, GCs were isolated from Cumulus-Oocyte-Complexes (COCs) from bovine ovaries, cultured in vitro for 7 days, or until confluent, and cryopreserved at passage 1 (P1). For experimentation, cells were thawed, cultured until passage 2 (P2), serum restricted for 24-h and treated for 24-h in one of five groups: control, vehicle (1:1:18 ethanol: tween: saline) and three clinically relevant THC doses (0.032, 0.32 and 3.2 μM). Global methylation was assessed by measuring 5-mC and 5-hmC levels with flow cytometry. To assess mRNA and protein expression of methylation regulators and miRNA profiles, qPCR and Western Blotting were utilized. Shapiro-Wilk test was used to determine normality within datasets. One-way ANOVA was applied to determine statistical significance using GraphPad Prism 6.0.0.

RESULTS

Results indicate a significant decrease (p = 0.0435) in 5-mC levels following low THC exposure, while no changes were observed in 5-hmC levels. A significant increase in DNMT1 following high THC exposure at the RNA level (p < 0.05) and a significant increase following low THC exposure at the protein level (p = 0.0048) were also observed. No significant differences were observed in DNMT3a/3b, TDG, TET1/2/3 mRNAs or in any of the miRNAs analyzed.

CONCLUSIONS

This research suggests that THC mainly affects DNA methylation, but not miRNA profiles, ultimately altering gene expression and likely impairing oocyte competence, maturation, and fertilization potential.

Cytogenotoxicity and inflammatory response in liver of rats exposed to different doses of cannabis nano emulsions

Cannabis is the most used illicit substance for recreational purposes around the world. However, it has become increasingly common to witness the use of approved cannabis preparations for symptoms management in various diseases. The aim of this study was to investigate the effects of cannabis nano emulsion in the liver of Wistar rats, with different proportions of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). For this, a total of 40 male Wistar rats were distributed into 5 groups, as follows (n = 8 per group): Control: G1, Experimental group (G2): treated with cannabis nano emulsion (THC and CBD) at a dose of 2.5 mg/kg, Experimental group (G3): treated with cannabis nano emulsion (THC and CBD) at a dose of 5 mg/kg, Experimental group (G4): treated with cannabis nano emulsion (CBD) at a dose of 2.5 mg/kg; Experimental group (G5): treated with cannabis nano emulsion (CBD) at a dose of 5 mg/kg. Exposure to the nano emulsion was carried out for 21 days, once a day, orally (gavage). Our results showed that cannabis nano emulsions at higher doses (5 mg/kg), regardless of the composition, induced histopathologic changes in the liver (G3 and G5) in comparison with the control group. In line with that, placental glutathione S-transferase (GST-P) positive foci increased in both G3 and G5 (p < 0.05), as well as the immune expression of Ki-67, vascular endothelial growth factor (VEGF) and p53 (p < 0.05). Also, the nano emulsion intake induced an increase in the number of micronucleated hepatocytes in G5 (p < 0.05) whereas G3 showed an increase in binucleated cells (p < 0.05). As for metanuclear alterations, karyolysis and pyknosis had an increased frequency in G3 (p < 0.05). Taken together, the results show that intake of cannabis nano emulsion may induce degenerative changes and genotoxicity in the liver in higher doses, demonstrating a clear dose-response relationship.

Hormetic effects of a cannabinoid system component, 2-arachidonoyl glycerol, on cell viability and expression profile of growth factors in cultured mouse Sertoli cells: Friend or foe of male fertility?

The generally undesired effects of exocannabinoids on male reproduction include alterations in testicular cell proliferation and function, as well as apoptosis induction. However, this paradigm has been challenged by the ability of endocannabinoids to regulate reproductive function. The present study addresses these paradoxical facts by investigating the effects of the endocannabinoid 2-arachidonoyl glycerol (2-AG) on mouse Sertoli cells' survival and apoptosis, with a mechanistic insight into Sertoli cell-based growth factors' production. The Mus musculus Sertoli cell line (TM4) was exposed to different concentrations of 2-AG, and cell viability was evaluated using MTT assay. Growth factors' gene and protein expressions were analyzed through RT-PCR and western blotting. 2-AG concentration dependently increased TM4 viability, with a slight increase starting at 0.0001 µM, a peak of 190% of the control level at 1 µM, and a decrease at 3 µM. Moreover, 2-AG paradoxically altered mRNA expression of caspase-3 and growth factors. Caspase-3 mRNA expression was down-regulated, and growth factors mRNA and protein expression were up-regulated when using a low concentration of 2-AG (1 μM). Opposite effects were observed by a higher concentration of 2-AG (3 μM). These paradoxical effects of 2-AG can be explained through the concept of hormesis. The results indicate the pivotal role of 2-AG in mediating Sertoli cell viability and apoptosis, at least in part, through altering growth factors secretion. Furthermore, they suggest the involvement of endocannabinoids in Sertoli cell-based physiological and pathological conditions and reflect the ability of abnormally elevated 2-AG to mimic the actions of exocannabinoids in reproductive dysfunction.

In vitro evaluation of cell viability and expression profile of growth factors in mouse Sertoli cells exposed to Delta-9-tetrahydrocannabinol: a mechanistic insight into the cannabinoid-induced testicular toxicity

The potentially adverse effects of cannabis (marijuana), a common leisure compound, on male reproductive performance are a reason for concern. δ-9-tetrahydrocannabinol (THC), the primary active component of marijuana alters testicular cells' proliferation and function which affects male fertility and causes testicular cells dysfunction and apoptosis. The main objective of this study was to investigate the possible mechanism underlying the toxic effects of THC with a mechanistic insight into Sertoli cell-based reproductive dysfunction. The Mus musculus Sertoli cell line (TM4) was cultured and exposed to different concentrations of THC and, MTT (3-(4, 5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was then performed for evaluating cell viability. The expression of caspase-3 gene and genes related to growth factors were analyzed by real-time RT-PCR. Western blotting was performed for evaluating protein expression level. THC concentration-dependently decreased the TM4 viability with a significant effect starting at concentration of 1 μM and reaching about 75% of the control level at the concentration of 50 μM (IC25). Moreover, caspase-3 mRNA expression levels significantly increased while growth factors mRNA levels decreased in THC-exposed cells compared to unexposed cells. There was also a significant reduction in related protein levels in THC group. Administration of the THC promotes cytotoxic and apoptotic effects on TM4 cells partly through down-regulation of growth factors expression. Increased apoptosis, over expression of caspase-3, and down-regulation of growth factors expression in Sertoli cells exposed to THC may be a reflection of THC-induced testicular toxicity, which may be partly involved in infertility associated with marijuana smoking or medical cannabis use.

Effects of low-dose ketamine infusion on vascular endothelial growth factor and matrix metalloproteinase-9 among patients with treatment-resistant depression and suicidal ideation

BACKGROUND

Evidence indicates that vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) influence the pathophysiology of depression. However, whether low-dose ketamine regulates VEGF and MMP-9 levels and whether changes in VEGF and MMP-9 levels are associated with the antidepressant and antisuicidal effects of ketamine remained unclear.

METHODS

Forty-eight patients with treatment-resistant depression and strong suicidal ideation (TRD-SI) were randomly assigned to a single infusion of 0.5-mg/kg ketamine or 0.045-mg/kg midazolam. The Montgomery-Åsberg Depression Rating Scale (MADRS) and Columbia-Suicide Severity Rating Scale-Ideation Severity Subscale (CSSRS-ISS) were used at baseline and subsequently at several postinfusion timepoints. VEGF and MMP-9 serum levels were analyzed at baseline and on day 3 postinfusion.

RESULTS

After adjustment for baseline levels, no significant differences in VEGF (p = .912) and MMP-9 (p = .758) levels were identified on day 3 postinfusion between the study groups. Baseline VEGF levels but not MMP-9 levels were negatively associated with MADRS and CSSRS-ISS scores following infusion.

DISCUSSION

A single infusion of low-dose ketamine did not alter the VEGF and MMP-9 levels of the patients with TRD-SI. Higher baseline VEGF levels were associated with greater antidepressant and antisuicidal effects of single low-dose ketamine infusion.

The Endocannabinoid System as a Potential Therapeutic Target for HIV-1-Associated Neurocognitive Disorder

Background: Despite the successful introduction of combined antiretroviral therapy, the prevalence of mild to moderate forms of HIV-associated neurocognitive disorders (HAND) remains high. It has been demonstrated that neuronal injury caused by HIV is excitotoxic and inflammatory, and it correlates with neurocognitive decline in HAND. Endocannabinoid system (ECS) protects the body from excitotoxicity and neuroinflammation on demand and presents a promising therapeutic target for treating HAND. Here, we firstly discuss the potential pathogenesis of HAND. We secondly discuss the structural and functional changes in the ECS that are currently known among HAND patients. We thirdly discuss current clinical and preclinical findings concerning the neuroprotective and anti-inflammatory properties of the ECS among HAND patients. Fourth, we will discuss the interactions between the ECS and neuroendocrine systems, including the hypothalamic-pituitary-adrenocortical (HPA) and hypothalamic-pituitary-gonadal (HPG) axes under the HAND conditions. Materials and Methods: We have carried out a review of the literature using PubMed to summarize the current state of knowledge on the association between ECS and HAND. Results: The ECS may be ideally suited for modulation of HAND pathophysiology. Direct activation of presynaptic cannabinoid receptor 1 or reduction of cannabinoid metabolism attenuates HAND excitotoxicity. Chronic neuroinflammation associated with HAND can be reduced by activating cannabinoid receptor 2 on immune cells. The sensitivity of the ECS to HIV may be enhanced by increased cannabinoid receptor expression in HAND. In addition, indirect regulation of the ECS through modulation of hormone-related receptors may be a potential strategy to influence the ECS and also alleviate the progression of HAND due to the reciprocal inhibition of the ECS by the HPA and HPG axes. Conclusions: Taken together, targeting the ECS may be a promising strategy to alleviate the inflammation and neurodegeneration caused by HIV-1 infection. Further studies are required to clarify the role of endocannabinoid signaling in HIV neurotoxicity. Strategies promoting endocannabinoid signaling may slow down cognitive decline of HAND are proposed.