Cannabis has long been used for its medicinal and psychoactive properties. With the relatively new adoption of formal medicinal cannabis regulations worldwide, the study of cannabinoids, both endogenous and exogenous, has similarly flourished in more recent decades. In particular, research investigating the role of cannabinoids in regeneration and neurodevelopment has yielded promising results in vertebrate models. However, regeneration-competent vertebrates are few, whereas a myriad of invertebrate species have been established as superb models for regeneration. As such, this review aims to provide a comprehensive summary of the endocannabinoid system, with a focus on current advances in the area of endocannabinoid system contributions to invertebrate neurodevelopment and regeneration.

There is a growing interest in the endocannabinoid system and the gut microbiota. Both areas have been suggested to play a role in endometriosis, however this is yet to be studied comprehensively. The purpose of this narrative review is to identify the gaps in endometriosis research in the context of these two areas. It underscores the limited knowledge regarding the involvement of the endocannabinoid system and gut microbiota in endometriosis. Further research in these areas is essential to unlock the therapeutic potential of cannabis and enhance the understanding of endometriosis pathogenesis.

The endocannabinoid system (eCB) began to be studied from the identification of the molecular structures present in the cannabis sativa plant. The ECS is constituted of cannabinoid receptors, endogenous ligands and all the associated enzymatic apparatus responsible for maintaining homeostasis. Several physiological effects of cannabinoids are exerted through interaction with various receptors such as CB1 and CB2 receptors, vanilloid receptors, and the recently discovered [GPCRs (GPR55, GPR3, GPR6, GPR12 and GPR19). Endogenous ligands such anandamide and 2-arachidonoylglycerol might modulate these receptors. eCB has proved to play a critical role in some human diseases and has been extensively studied due to its wide therapeutic potential and because it is a promising target for the development of new drugs. Phytocannabinoids and synthetic cannabinoids have shown varied affinities to eCB, which are relevant to the treatment of various diseases. They may also have potential as lead compounds in the development of cannabinoid-based pharmaceuticals for a variety of diseases. Furthermore, Integrative and Complementary Health Practices (ICHP) appear to influence the endocannabinoid system through modulation. This review will show a description of ECS components and discuss how phytocannabinoids, other exogenous compounds, and PICS may operate the eCB balance.

Critically ill patients with sepsis require a multidisciplinary approach, as this situation implies multiorgan distress, with most of the bodily biochemical and cellular systems being affected by the condition. Moreover, sepsis is characterized by a multitude of biochemical interactions and by dynamic changes of the immune system. At the moment, there is a gap in our understanding of the cellular, genetic, and molecular mechanisms involved in sepsis. One of the systems intensely studied in recent years is the endocannabinoid signaling pathway, as light was shed over a series of important interactions of cannabinoid receptors with biochemical pathways, specifically for sepsis. Furthermore, a series of important implications on inflammation and the immune system that are induced by the activity of cannabinoid receptors stimulated by the delta-9-tetrahidrocannabinol and cannabinol have been noticed. The aim of this review paper was to present, in detail, the important mechanisms modulated by the endocannabinoid signaling pathway, as well as of the molecular and cellular links it has with sepsis. At the same time, we wish to present the possible implications of cannabinoids in the most important biological pathways involved in sepsis, such as inflammation, redox activity, immune system, and epigenetic expression.

Background: The endocannabinoid system (ECS) is a very heterogeneous array consisting of many proteins like ligands, enzymes and receptors synthetized in various tissues and immunity cells. The main endogenous ligands are unsaturated fatty acid derivatives like anandamide(AEA), 2-arachidonoylglycerol(2-AG), but many others are under study. Endocannabinoids are involved in both physiological and pathological conditions. ECS plays an important role in the regulation of main processes which lead to cancer and also in sex steroid hormone-related cancers. Methods: With focus on gynaecological cancers, main papers and review articles, up to April 2018, on the role of the ECS, were acquired by PubMed searches using the search terms: ‘cancer’, ‘cannabinoid’, ‘endocannabinoid’, ‘gynaecology’ and ‘malignancy’. Results: The review of recent literature data showed the involvement of the endocannabinoid system in numerous physiological and pathological conditions of the female genital tract up to the development of gynaecological malignancy as cervical, endometrial and ovarian cancer. Conclusions: The endocannabinoid system has an important role in antitumor actions involving different signalling receptor and receptor-independent pathways. It represents an exciting challenge to researchers for its potential use in diagnosis and treatment of all gynaecological malignancies

Inflammatory granulocytes are characterized by oxidative burst, which may promote oxidative stress and lipid modification both in affected tissues and on systemic level. On the other hand, redox signaling involving lipid peroxidation products acting as second messengers of free radicals play important, not yet fully understood, roles in pathophysiology of inflammation and various stress-associated disorders. Therefore, the aim of this study was to evaluate the onset of oxidative stress and alterations of enzyme-dependent lipid metabolism resulting from redox imbalance in granulocytes and plasma obtained from patients with psoriasis vulgaris or psoriatic arthritis, in comparison to the healthy subjects. The results obtained revealed enhanced activity of pro-oxidant enzymes NADPH and xanthine oxidases in granulocytes, with a decrease of enzymatic and non-enzymatic antioxidants in plasma of psoriatic patients. The Nrf2 and its regulators were increased in both forms of psoriasis, while HO-1 levels were increased only in psoriasis vulgaris. Redox imbalance was associated with decreased levels of phospholipids and of free PUFAs, but with enhanced activity of enzymes involved in lipid metabolism (PLA2, PAF-AH COX1/2) and increased lipid peroxidation products 4-hydroxynonenal (4-HNE), isoprostanes and neuroprostanes. Increased endocannabinoids and GPR55 were observed in both forms of the disease, while expression of CB1 was increased only in pateints with psoriatic arthritis, opposite to CB2, which was increased only in psoriasis vulgaris. Protein modifications by ROS and lipid peroxidation product 4-HNE promoted apoptosis of granulocytes by increased caspases in both forms of psoriasis. This study indicates that excessive activation of granulocytes, causing oxidative stress and lipid modifications, is an important pathophysiology of psoriasis. Consequently, lower Nrf2 activity and CB2 expression may promote progression of psoriasis into advanced, arthritic form of the disease.

Cognitive functions are based on neuronal plasticity, which is provided by various mechanisms involving numerous bioactive molecules, the most important of which are endocannabinoids (eCBs). Over the past three decades, a lot of data have been accumulated on the involvement of eCBs in the mechanisms of memory and other cognitive functions. These functions are impaired in neurodegenerative diseases such as Alzheimer's disease (AD) and temporal lobe epilepsy (TLE). The main pathological feature of neurons in AD and TLE is increased excitability; therefore, an activation of the endocannabinoid system, which controls cellular excitation, may be a promising approach in their therapy. The available information about the effect of (endo)cannabinoids on cognitive functions is contradictory, which may depend on the drugs used, their dose, and the experimental conditions. There is an extensive literature indicating a protective effect of cannabinoids in the treatment of neurodegenerative diseases in humans and in animal models of cognitive deficits. This review, focusing on the recent researches, is devoted to the analysis of the effects of endocannabinoid system activation on cognitive functions in norm and in the brain with neurodegeneration that occurs in AD and TLE diseases. Possible reasons for inconsistencies in the available data are discussed.

The endocannabinoid system has been found to be pervasive in mammalian species. It has also been described in invertebrate species primitive as the Hydra. Insects apparently are devoid of this otherwise ubiquitous system that provides homeostatic balance to the nervous and immune systems, as well as many other organ systems. The endocannabinoid system (ECS) has been defined to consist of three parts: 1. Endogenous ligands, 2. G-protein coupled receptors (GPCRs), and 3. Enzymes to degrade and recycle the ligands. Two endogenous molecules have been identified as ligands in the ECS to date. These are the endocannabinoids: Anandamide (arachidonoyl ethanolamide) and 2-AG (2-arachidonoyl glycerol). Two G-coupled protein receptors have been described as part of this system, with other putative GPC being considered. Coincidentally, the phytochemicals produced in large quantities by the Cannabis sativa L plant, and in lesser amounts by other plants, can interact with this system as ligands. These plant-based cannabinoids are termed, phytocannabinoids. The precise determination of the distribution of cannabinoid receptors in animal species is an ongoing project, with the canine cannabinoid receptor distribution currently receiving the most interest in non-human animals.

N-palmitoylethanolamine (PEA) is an endocannabinoid-like compound first encountered within lipid fractions of specific foods and has intrigued researchers since the 1950s due to its therapeutic effects. This study aims to explore the therapeutic promise held by PEA as an anti-inflammatory and immunomodulatory agent. Therapeutic impact of PEA reverberates across diverse physiological systems, as the central nervous system, gastrointestinal tract, vascular network, digestive and respiratory system. Additionally, it was effective in pain management, reduction of inflammation and immune responses. These attributes have fostered collaborations targeting conditions such as Alzheimer's disease, multiple sclerosis, cerebral ischemia, neuroinflammation, general inflammation, pain, coagulopathy, steatohepatitis, and acute lung injury. PEA operates both independently and in synergy with other compounds, like paracetamol, luteolin, and oxymetazoline. This efficacy stems from its interactions with pivotal targets including PPARα, PPAR-δ, PPAR-γ, CB1, CB2, GPR55, and TRPV1. Additionally, PEA exerts a direct influence on the inflammatory cascade, orchestrating precise adjustments in immune responses. Numerous animal studies have elucidated the inherent potential of PEA. Nevertheless, the imperative of reinforcing clinical investigation is evident. This review notably underscores the pivotal necessity for methodologically rigorous clinical trials to definitively establish the translational efficacy of PEA in ameliorating diverse inflammatory pathologies within the human milieu.

Background: Alkylresorcinols (ARs) are polyphenolic compounds with a wide spectrum of biological activities and potentially implicated in the regulation of host metabolism. The present study is aimed to establish whether ARs can be produced by human gut microbiota and to evaluate alterations in the content of ARs in stool samples of C57BL and db/db and LDLR (-/-) mice in dependence on diet specifications and olivetol (5-n-pentylresorcinol) supplementation in order to estimate a regulatory potential of ARs. Methods: The quantita-tive analysis of ARs levels in mice stool samples was performed using gas chromatography with mass spectrometric detection; fecal microbiota transplantation (FMT) from human donor to germ-free mice was performed to explore whether the intestinal microbiota could produce ARs molecules. Results: A significant increase in the amounts of individual mem-bers of ARs homologues in stool samples was revealed in 14 days after FMT. 5-n-Pentylresorcinol supplementation to a regular-chow diet influences the amounts of sev-eral ARs in stool of C57BL/6 and LDLR (-/-), but not db/db mice. Conclusions: For the first time, we have shown that several ARs can be produced by the intestinal microbiota. Taking into account, that AR concentrations in human serum are correlated with LPS levels and with microbiota diversity indexes in human stool samples, it can be assumed that ARs may serve as quorum-sensing molecules, influencing gut microbiota composition and host me-tabolism as well.

The Asian elephant (Elephas maximus) is one of the largest herbivore mammals in the world. A portion of the total elephant population is under human care, where health problems such as skin lesions and decreased appetite are reported. The objective of this study was to apply the therapeutic properties of cannabidiol (CBD) to aid treatment of palmar abscesses and a suboptimal food intake in a female Asian elephant in Mexico. A CBD-isolate compounded medication was administered orally at a dose of 0.05 mg/kg/day. CBD administration showed positive effects such as reduction in abscess size, decreased food selectivity, increased food intake, weight gain and increased mobility. More research in elephants is needed to understand their cannabinoid pharmacodynamics and pharmacokinetics and proposing a dosage range and therapeutic applications for this species.

Paracetamol or acetaminophen (N-acetyl-para-aminophenol, APAP) is an analgesic and antipy-retic drug commonly used worldwide, implicated in numerous intoxications due to overdose, and causing serious liver damage. APAP can cross the blood-brain barrier and affects brain function in numerous ways including pain signals, temperature regulation, neuroimmune response and emotional behavior; however, its effect on adult neurogenesis has not been thoroughly investi-gated. We analyze the effect of APAP overdose (750 mg/kg/day), for 3 and 4 consecutive days and after cessation of APAP administration for 6 and 15 days, on cell proliferation and survival in two relevant neurogenic zones: the subgranular zone of the dentate gyrus and the hypothalamus. The involvement of liver damage (plasma transaminases), neuronal activity (c-Fos) and astroglia (GFAP) was also evaluated. Our results indicated that repeated APAP overdoses were associated with inhibition of adult neurogenesis in a context of elevated liver transaminase levels, neuronal hyperactivity and as-trogliosis. These effects were partially reversed after cessation of APAP administration for 6 and 15 days. In conclusion, these results suggest that APAP overdose impairs adult neurogenesis in the hip-pocampus and hypothalamus, a fact that may contribute to the effects of APAP on brain function.

Background: Mounting evidence supports the role of the endocannabinoid system in neurophysiology, includ-ing blood-brain barrier (BBB) function. Recent work has demonstrated that activation of endocannabinoid re-ceptors can mitigate insults to the BBB during neurological disorders, like traumatic brain injury, cortical spreading depression and stroke. As alterations to the BBB are associated with worsening clinical outcomes in these conditions, studies herein sought to examine the impact of endocannabinoid depletion on BBB integrity. Methods: Barrier integrity was investigated in vitro via bEnd.3 cell monolayers to assess endocannabinoid syn-thesis, barrier function, calcium influx, junctional protein expression, and proteome-wide changes. Results: In-hibition of 2-AG synthesis using DAGLα inhibition and siRNA inhibition of DAGLα led to loss of barrier in-tegrity via altered expression of VE-cadherin, which could be partially rescued by exogenous application of 2-AG. Moreover, the deleterious effects of DAGLα inhibition on BBB integrity showed both calcium and PKC (protein kinase C)-dependency. Conclusions: These data indicate that disruption of 2-AG homeostasis in brain endothelial cells, in the absence of insult, is sufficient to disrupt BBB integrity thus supporting the role of the endocannabinoid system in neurovascular disorders.