Induction of apoptosis by cannabidiol and its main metabolites in human Leydig cells

Cannabidiol (CBD) is one of the most prevalent and abundant cannabinoids extracted from the plant Cannabis sativa. CBD has been reported to induce male reproductive toxicity in animal models. In this study, we examined the effects of CBD and its main metabolites, 7-carboxy-CBD and 7-hydroxy-CBD, on primary human Leydig cells, which play a crucial role in male reproductive health. Our results showed that CBD, at concentrations below the Bayesian benchmark dose (BMD)50, inhibited the growth of human Leydig cells by arresting the cell cycle at G1/S transition, disrupting cell cycle regulators, and decreasing DNA synthesis. Concentration-response transcriptomic profiling identified that apoptosis was one of the top biological processes significantly affected by treatment with CBD for 24 h. The occurrence of apoptosis was confirmed by increased activation of caspase-3/7 and an increased proportion of annexin V and propidium iodide (PI)-positive cells. Similar to CBD, both 7-carboxy-CBD and 7-hydroxy-CBD decreased cell viability and induced apoptosis after treatment for 24 h. 7-Hydroxy-CBD and 7-carboxy-CBD showed lower cytotoxicity than CBD, and 7-carboxy-CBD had the lowest cytotoxicity among the three compounds. Our findings revealed that CBD and its main metabolites can cause adverse effects on primary human Leydig cells.

Review of the oral toxicity of cannabidiol (CBD)

Information in the published literature indicates that consumption of CBD can result in developmental and reproductive toxicity and hepatotoxicity outcomes in animal models. The trend of CBD-induced male reproductive toxicity has been observed in phylogenetically disparate organisms, from invertebrates to non-human primates. CBD has also been shown to inhibit various cytochrome P450 enzymes and certain efflux transporters, resulting in the potential for drug-drug interactions and cellular accumulation of xenobiotics that are normally transported out of the cell. The mechanisms of CBD-mediated toxicity are not fully understood, but they may involve disruption of critical metabolic pathways and liver enzyme functions, receptor-specific binding activity, disruption of testosterone steroidogenesis, inhibition of reuptake and degradation of endocannabinoids, and the triggering of oxidative stress. The toxicological profile of CBD raises safety concerns, especially for long term consumption by the general population.

Cannabidiol-induced transcriptomic changes and cellular senescence in human Sertoli cells

Cannabidiol (CBD), one of the major cannabinoids in the plant Cannabis sativa L., is the active ingredient in a drug approved for the treatment of seizures associated with certain childhood-onset epileptic disorders. CBD has been shown to induce male reproductive toxicity in multiple animal models. We previously reported that CBD inhibits cellular proliferation in the mouse Sertoli cell line TM4 and in primary human Sertoli cells. In this study, using a transcriptomic approach with mRNA-sequencing analysis, we identified molecular mechanisms underlying CBD-induced cytotoxicity in primary human Sertoli cells. Analysis of differentially expressed genes demonstrated that DNA replication, cell cycle, and DNA repair were the most significantly affected pathways. We confirmed the concentration-dependent changes in the expression of key genes in these pathways using real-time PCR. mRNA sequencing showed upregulation of a group of genes tightly associated with the senescence-associated secretory phenotype (SASP) and with the activation of the p53 signaling pathway, a key upstream event in cellular senescence. Prolonged treatment of 10 μM CBD-induced cellular senescence, as evidenced by the stable cessation of proliferation and the activation of senescence-associated β-galactosidase (SA-β-gal), 2 hallmarks of senescence. Additionally, using real-time PCR and Western blotting assays, we observed that CBD treatment increased the expression of p16, an important marker of cellular senescence. Taken together, our results show that CBD exposure disturbs various interrelated signaling pathways and induces cellular senescence in primary human Sertoli cells.

In vitro effects of cannabidiol and its main metabolites in mouse and human Sertoli cells

Cannabidiol (CBD) is a major cannabinoid present in extracts of the plant Cannabis sativa (marijuana). While the therapeutic effects of CBD on epilepsy have been demonstrated, less is understood regarding its potential adverse effects. Recent studies revealed that CBD induced toxicity in the male reproductive system of animal models. In this study, we used TM4, an immortalized mouse Sertoli cell line, and primary human Sertoli cells to evaluate the toxicities of CBD and its main metabolites, 7-carboxy-CBD and 7-hydroxy-CBD. CBD induced concentration- and time-dependent cytotoxicity in mouse and human Sertoli cells, which mainly resulted from the inhibition of the G1/S-phase cell cycle transition. CBD also inhibited DNA synthesis and downregulated key cell cycle proteins. Moreover, CBD reduced the mRNA and protein levels of a functional marker, Wilms' tumor 1. Similar to CBD, 7-carboxy-CBD and 7-hydroxy-CBD inhibited cellular proliferation and decreased DNA synthesis. 7-Carboxy-CBD was less cytotoxic than CBD, while 7-hydroxy-CBD showed comparable cytotoxicity to CBD in both mouse and human Sertoli cells. Compared to mouse Sertoli cells, CBD, 7-hydroxy-CBD, and 7-carboxy-CBD were more cytotoxic in human Sertoli cells. Our results indicate that CBD and its main metabolites can inhibit cell proliferation in mouse and human Sertoli cells.

Studying NB-LRR immune receptor localization by agroinfiltration transient expression

NB-LRR immune receptors in plants play dual roles as sentries and as activators of defense. The site in the cell where these activities take place can be different for different NB-LRRs. Furthermore, recognition and defense activation can occur in distinct subcellular compartments. Therefore, determining the subcellular localization of NB-LRRs is a key step toward understanding how they function. Recent advances in confocal microscopy enable high-resolution imaging of proteins in live cells. Agroinfiltration in the Nicotiana benthamiana model plant system is a convenient way of expressing proteins for localization studies. This chapter explains how to use N. benthamiana to transiently express NB-LRRs for confocal fluorescence microscopy.

The leucine-rich repeat domain in plant innate immunity: a wealth of possibilities

The innate immune system of both plants and animals uses immune receptors to detect pathogens and trigger defence responses. Despite having distinct evolutionary origin, most plant and animal immune receptors have a leucine-rich repeat (LRR) domain. The LRR domain adopts a slender conformation that maximizes surface area and has been shown to be ideal for mediating protein-protein interactions. Although the LRR domain was expected to be a platform for pathogen recognition, the NB-LRR class of plant innate immune receptors uses its LRR domain to carry out many other roles. This review discusses the domain architecture of plant LRRs and the various roles ascribed to this motif.

Expert panel method for nurse staffing and resource management

The Expert Panel Nurse Staffing and Resource Management Method is a bold new approach for the identification of nurse staffing requirements and the management of resources. Expert panels comprised of those most knowledgeable of the patient population and the uniqueness of specific patient care areas identify staff needed to meet clinical, administrative, education, continuous quality improvement, and research needs. In addition, the expert panels explore opportunities for systems improvements, work redesign, and administrative restructuring within the context of budgetary realities.