Cannabinoids are a group of organic chemical compounds that affect the endocannabinoid system. The endocannabinoid system (ECS) is a biochemical system responsible for regulating many physiological and cognitive functions. It consists of endogenous cannabinoids, enzymes that regulate the biosynthesis and biodegradation of endogenous cannabinoids and cannabinoid receptors (CB1, CB2). It regulates cognitive processes in the central nervous system, as well as the functioning of the immune system and the proper course of the inflammatory reaction. There are three groups of canna- binoids: endocannabinoids, phytocannabinoids, and synthetic cannabinoids. Phytocannabinoids are obtained mainly for medical purposes from hemp inflorescences (Cannabis sativa). There are over 100 cannabinoids that have been isolated from Cannabis sativa tissues, the most well-known of which are: tetrahydrocannabinol (THC), cannabidiol (CBD), cannabinol, cannabigerol, tetrahydrocannabivarin, cannabidivarin, cannabichromene. The widespread use of phytocannabinoids in medicine is limited by the possibility of undesirable psychoactive side effects, mainly due to one compound – THC. Unlike THC, CBD is devoid of psychogenic properties, which significantly affects the safety of therapy and does not generate legal problems. Hemp inflorescence extracts are successfully used in the treatment of many diseases in humans, although the use of hemp preparations in veterinary medicine has been unknown for many years. However, they have found documented use in the treatment of degenerative joint diseases, epilepsy, and behavioral disorders. This work aims to systematize and summarize the available knowledge on the use of cannabidiol in the treatment of canine and feline diseases.
Phytosterols are a large group of substances belonging to sterols—compounds naturally occurring in the tissues of plants, animals, and humans. The most well-known animal sterol is cholesterol. Among phytosterols, the most significant compounds are β-sitosterol, stigmasterol, and campesterol. At present, they are mainly employed in functional food products designed to counteract cardiovascular disorders by lowering levels of ‘bad’ cholesterol, which stands as their most extensively studied purpose. It is currently understood that phytosterols may also alleviate conditions associated with the gastrointestinal system. Their beneficial pharmacological properties in relation to gastrointestinal tract include anti-inflammatory and hepatoprotective activity. Also, the anti-cancer properties as well as the impact on the gut microbiome could be a very interesting area of research, which might potentially lead to the discovery of their new application. This article provides consolidated knowledge on a new potential use of phytosterols, namely the treatment or prevention of gastrointestinal diseases. The cited studies indicate high therapeutic efficacy in conditions such as peptic ulcer disease, IBD or liver failure caused by hepatotoxic xenobiotics, however, these are mainly in vitro or in vivo studies. Nevertheless, studies to date indicate their therapeutic potential as adjunctive treatments to conventional therapies, which often exhibit unsatisfactory efficacy or serious side effects. Unfortunately, at this point there is a lack of significant clinical study data to use phytosterols in clinical practice in this area.
Abstract Treatment of solid tumors remains challenging and therapeutic strategies require continuous development. Tumor-infiltrating macrophages play a pivotal role in tumor dynamics. Here, we present a Macrophage-Drug Conjugate (MDC) platform technology that enables loading macrophages with ferritin-drug complexes. We first show that macrophages actively take up human heavy chain ferritin (HFt) in vitro via macrophage scavenger receptor 1 (MSR1). We further manifest that drug-loaded macrophages transfer ferritin to adjacent cancer cells through a process termed ‘TRAnsfer of Iron-binding protein’ (TRAIN). The TRAIN process requires direct cell-to-cell contact and an immune synapse-like structure. At last, MDCs with various anti-cancer drugs are formulated with their safety and anti-tumor efficacy validated in multiple syngeneic mice and orthotopic human tumor models via different routes of administration. Importantly, MDCs can be prepared in advance and used as thawed products, supporting their clinical applicability. This MDC approach thus represents a promising advancement in the therapeutic landscape for solid tumors.
Proteins, as a major component of organisms, are considered the preferred biomaterials for drug delivery vehicles. Hemoglobin (Hb) has been recently rediscovered as a potential drug carrier, but its use for biomedical applications still lacks extensive investigation. To further explore the possibility of utilizing Hb as a potential tumor targeting drug carrier, we examined and compared the biodistribution of Hb in healthy and lung tumor-bearing mice, using for the first time 89Zr labelled Hb in a positron emission tomography (PET) measurement. Hb displays a very high conjugation yield in its fast and selective reaction with the maleimide-deferoxamine (DFO) bifunctional chelator. The high-resolution X-ray structure of the Hb-DFO complex demonstrated that cysteine β93 is the sole attachment moiety to the αβ-protomer of Hb. The Hb-DFO complex shows quantitative uptake of 89Zr in solution as determined by radiochromatography. Injection of 0.03 mg of Hb-DFO-89Zr complex in healthy mice indicates very high radioactivity in liver, followed by spleen and lungs, whereas a threefold increased dosage results in intensification of PET signal in kidneys and decreased signal in liver and spleen. No difference in biodistribution pattern is observed between naïve and tumor-bearing mice. Interestingly, the liver Hb uptake did not decrease upon clodronate-mediated macrophage depletion, indicating that other immune cells contribute to Hb clearance. This finding is of particular interest for rapidly developing clinical immunology and projects aiming to target, label or specifically deliver agents to immune cells.
In vivo tracking of administered cells chosen for specific disease treatment may be conducted by diagnostic imaging techniques preceded by cell labeling with special contrast agents. The most commonly used agents are those with radioactive properties, however their use in research is often impossible. This review paper focuses on the essential aspect of cell tracking with the exclusion of radioisotope tracers, therefore we compare application of different types of non-radioactive contrast agents (cell tracers), methods of cell labeling and application of various techniques for cell tracking, which are commonly used in preclinical or clinical studies. We discuss diagnostic imaging methods belonging to three groups: (1) Contrast-enhanced X-ray imaging, (2) Magnetic resonance imaging, and (3) Optical imaging. In addition, we present some interesting data from our own research on tracking immune cell with the use of discussed methods. Finally, we introduce an algorithm which may be useful for researchers planning leukocyte targeting studies, which may help to choose the appropriate cell type, contrast agent and diagnostic technique for particular disease study.
Animal experiments, despite their controversial nature, play an indispensable role in scientific advancement and led to numerous significant discoveries. The supervision of veterinarians in the realm of in vivo research holds immense importance. However, this particular aspect of veterinary medicine, distinct from their other activities, can pose ethical challenges. Veterinarians are entrusted with the prevention of diseases, healing, and pain elimination, yet in the case of animal experiments, they witness intentional suffering and death. This article evaluates the ethical and professional deontological aspects of this issue. It explores the historical evolution of human-animal (including experimental) relationships and discusses how deontology stems from the definition of ethics. The article also examines codes of ethics for veterinarians, providing illustrative examples. It highlights that the actions of veterinarians in this domain align with their deontology and emphasises the role of veterinarians in in vivo research as viewed within current legal frameworks. In conclusion, the veterinarian's participation in animal research is both ethically and deontologically justified, and it is also a legal requirement.
In 2024, the United States was projected to experience 2 million new cancer diagnoses and approximately 611,720 cancer-related deaths, reflecting a broader global trend in which cancer cases are anticipated to exceed 35 million by 2050. This increasing burden highlights ongoing challenges in cancer treatment despite significant advances that have reduced cancer mortality by 31% since 1991. Key obstacles include the disease’s inherent heterogeneity and complexity, such as treatment resistance, cancer stem cells, and the multifaceted tumor microenvironment (TME). The TME—comprising various tumor and immune cells, blood vessels, and biochemical factors—plays a crucial role in tumor growth and resistance to therapies. Recent innovations in cancer treatment, particularly in the field of immuno-oncology, have leveraged insights into TME interactions. An emerging example is the FDA-approved therapy using tumor-infiltrating lymphocytes (TILs), demonstrating the potential of cell-based approaches in solid tumors. However, TIL therapy is just one of many strategies being explored. This review provides a comprehensive overview of the emerging field of immuno-oncology, focusing on how novel therapies targeting or harnessing components of the TME could enhance treatment efficacy and address persistent challenges in cancer care.
Cannabinoids and their receptors play a significant role in the regulation of gastrointestinal (GIT) peristalsis and intestinal barrier permeability. This review critically evaluates current knowledge about the mechanisms of action and biological effects of endocannabinoids and phytocannabinoids on GIT functions and the potential therapeutic applications of these compounds. The results of ex vivo and in vivo preclinical data indicate that cannabinoids can both inhibit and stimulate gut peristalsis, depending on various factors. Endocannabinoids affect peristalsis in a cannabinoid (CB) receptor-specific manner; however, there is also an important interaction between them and the transient receptor potential cation channel subfamily V member 1 (TRPV1) system. Phytocannabinoids such as Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) impact gut motility mainly through the CB1 receptor. They were also found to improve intestinal barrier integrity, mainly through CB1 receptor stimulation but also via protein kinase A (PKA), mitogen-associated protein kinase (MAPK), and adenylyl cyclase signaling pathways, as well as by influencing the expression of tight junction (TJ) proteins. The anti-inflammatory effects of cannabinoids in GIT disorders are postulated to occur by the lowering of inflammatory factors such as myeloperoxidase (MPO) activity and regulation of cytokine levels. In conclusion, there is a prospect of utilizing cannabinoids as components of therapy for GIT disorders.