A-series agent A-234: initial in vitro and in vivo characterization.

A-series agent A-234 belongs to a new generation of nerve agents. The poisoning of a former Russian spy Sergei Skripal and his daughter in Salisbury, England, in March 2018 led to the inclusion of A-234 and other A-series agents into the Chemical Weapons Convention. Even though five years have already passed, there is still very little information on its chemical properties, biological activities, and treatment options with established antidotes. In this article, we first assessed A-234 stability in neutral pH for subsequent experiments. Then, we determined its inhibitory potential towards human recombinant acetylcholinesterase (HssAChE; EC 3.1.1.7) and butyrylcholinesterase (HssBChE; EC 3.1.1.8), the ability of HI-6, obidoxime, pralidoxime, methoxime, and trimedoxime to reactivate inhibited cholinesterases (ChEs), its toxicity in rats and therapeutic effects of different antidotal approaches. Finally, we utilized molecular dynamics to explain our findings. The results of spontaneous A-234 hydrolysis showed a slow process with a reaction rate displaying a triphasic course during the first 72 h (the residual concentration 86.2%). A-234 was found to be a potent inhibitor of both human ChEs (HssAChE IC50 = 0.101 ± 0.003 µM and HssBChE IC50 = 0.036 ± 0.002 µM), whereas the five marketed oximes have negligible reactivation ability toward A-234-inhibited HssAChE and HssBChE. The acute toxicity of A-234 is comparable to that of VX and in the context of therapy, atropine and diazepam effectively mitigate A-234 lethality. Even though oxime administration may induce minor improvements, selected oximes (HI-6 and methoxime) do not reactivate ChEs in vivo. Molecular dynamics implies that all marketed oximes are weak nucleophiles, which may explain the failure to reactivate the A-234 phosphorus-serine oxygen bond characterized by low partial charge, in particular, HI-6 and trimedoxime oxime oxygen may not be able to effectively approach the A-234 phosphorus, while pralidoxime displayed low interaction energy. This study is the first to provide essential experimental preclinical data on the A-234 compound.

The new future perspective in corneal tissue utilisation - methods of preparation and preservation.

PURPOSE: The goal of our study is to find an optimal approach to the preparation and preservation of corneal stromal tissue. We want to compare different methods of corneal stromal tissue creation and storage to optimize the efficacy of this process under the conditions of an eye bank. After we find the most suitable method to create a safe high quality product, we want to prove the possibility of using a single donor cornea for more than one patient. We would also like to verify the feasibility of making more corneal lenticules after the removal of a corneal endothelium for DMEK transplantation. METHODS: We provided morphological (histology, scanning electron microscope) and microbiological analysis in order to compare different methods of corneal lenticule and corneal stromal lamellae preparation and preservation. We also tested the surgical handling of the tissue to secure a safe manipulation of the tissue for clinical use. We compared two methods of corneal lenticule preparation: microkeratome dissection and femtosecond laser. As methods of preservation, we tested hypothermia, cryopreservation at -80 degrees Celsius in DMSO (dimethyl sulfoxide) and storage at room temperature with glycerol. Some intrastromal lenticules and lamellae in each group were previously irradiated with gamma radiation of 25 kGy (KiloGray). RESULTS: Corneal stromal lamellae prepared with a microkeratome have a smoother cut - side surface compared to lamellae prepared with a femtosecond laser. Femtosecond laser preparation caused more irregularities on the surface and we detected more conglomerates of the fibrils, while lamellae made with microkeratome had more sparse network. Using femtosecond laser, we were able to make more than five lenticules from a single donor cornea. Gamma irradiation led to damage of collagen fibrils in corneal stroma and a loss of their regular arrangement. Corneal tissue stored in glycerol showed collagen fibril aggregates and empty spaces between fibrils caused by dehydration. Cryopreserved tissue without previous gamma irradiation showed the most regular structure of the fibrils comparable to storage in hypothermia. CONCLUSION: Our results suggest that formation of a corneal lenticule lamellae by microkeratome results in smoother corneal lenticules, while being much cheaper than formation by femtosecond laser. Gamma irradiation of 25 kGy caused damage of the collagen fibres as well as their network arrangement, which correlated with loss of transparency and stiffer structure. These changes impair possible surgical utilisation of gamma irradiated corneas. Storage in glycerol at room temperature and cryopreservation had similar outcomes and we believe that both methods are appropriate and safe for further clinical use .

Allogeneic Bone Impregnated with Biodegradable Depot Delivery Systems for the Local Treatment of Joint Replacement Infections: An In Vitro Study.

Although progress is evident in the effective treatment of joint replacement-related infections, it still remains a serious issue in orthopedics. As an example, the local application of antibiotics-impregnated bone grafts supplies the high drug levels without systemic side effects. However, antibiotics in the powder or solution form could be a risk for local toxicity and do not allow sustained drug release. The present study evaluated the use of an antibiotic gel, a water-in-oil emulsion, and a PLGA microparticulate solid dispersion as depot delivery systems impregnating bone grafts for the treatment of joint replacement-related infections. The results of rheological and bioadhesive tests revealed the suitability of these formulations for the impregnation of bone grafts. Moreover, no negative effect on proliferation and viability of bone marrow mesenchymal stem cells was detected. An ex vivo dissolution test of vancomycin hydrochloride and gentamicin sulphate from the impregnated bone grafts showed a reduced burst and prolonged drug release. The PLGA-based formulation proved to be particularly promising, as one-day burst release drugs was only 15% followed with sustained antibiotics release with zero-order kinetics. The results of this study will be the basis for the development of a new product in the Tissue Section of the University Hospital for the treatment of bone defects and infections of joint replacements.

Huprine Y - Tryptophan heterodimers with potential implication to Alzheimer's disease treatment.

The search for novel and effective therapeutics for Alzheimer's disease (AD) is the main quest that remains to be resolved. The goal is to find a disease-modifying agent able to confront the multifactorial nature of the disease positively. Herewith, a family of huprineY-tryptophan heterodimers was prepared, resulting in inhibition of cholinesterase and neuronal nitric oxide synthase enzymes, with effect against amyloid-beta (Aß) and potential ability to cross the blood-brain barrier. Their cholinesterase pattern of behavior was inspected using kinetic analysis in tandem with docking studies. These heterodimers exhibited a promising pharmacological profile with strong implication in AD.

Derivatives of montanine-type alkaloids and their implication for the treatment of Alzheimer's disease: Synthesis, biological activity and in silico study.

Alzheimers disease (AD) is the most common neurodegenerative disorder, characterized by neuronal loss and cognitive impairment. Currently, very few drugs are available for AD treatment, and a search for new therapeutics is urgently needed. Thus, in the current study, twenty-eight new derivatives of montanine-type Amaryllidaceae alkaloids were synthesized and evaluated for their ability to inhibit human recombinant acetylcholinesterase (hAChE) and butyrylcholinesterase (hBuChE). Three derivatives (1n, 1o, and 1p) with different substitution patterns demonstrated significant selective inhibitory potency for hAChE (IC50 < 5 µM), and one analog, 1v, showed selective hBuChE inhibition activity (IC50 = 1.73 ± 0.05 µM). The prediction of CNS availability, as disclosed by the BBB score, suggests that the active compounds in this survey should be able pass through the blood-brain barrier (BBB). Cytotoxicity screening and docking studies were carried out for the two most pronounced cholinesterase inhibitors, 1n and 1v.

Alkaloids of Zephyranthes citrina (Amaryllidaceae) and their implication to Alzheimer's disease: Isolation, structural elucidation and biological activity.

Twenty known Amaryllidaceae alkaloids of various structural types, and one undescribed alkaloid of narcikachnine-type, named narcieliine (3), have been isolated from fresh bulbs of Zephyranthes citrina. The chemical structures of the isolated alkaloids were elucidated by a combination of MS, HRMS, 1D and 2D NMR, and CD spectroscopic techniques, and by comparison with literature data. The absolute configuration of narcieliine (3) has also been determined. Compounds isolated in a sufficient quantity were evaluated for their in vitro acetylcholinesterase (AChE; E.C. 3.1.1.7), butyrylcholinesterase (BuChE; E.C. 3.1.1.8), and prolyl oligopeptidase (POP; E.C. 3.4.21.26) inhibition activities. Significant human AChE/BuChE (hAChE/hBuChE) inhibitory activity was demonstrated by the newly described alkaloid narcieliine (3), with IC50 values of 18.7 ± 2.3 µM and 1.34 ± 0.31 µM, respectively. This compound is also predicted to cross the blood-brain barrier (BBB) through passive diffusion. The in vitro data were further supported by in silico studies of 3 in the active site of hAChE/hBuChE.

Tacrine - Benzothiazoles: Novel class of potential multitarget anti-Alzheimers drugs dealing with cholinergic, amyloid and mitochondrial systems.

A series of tacrine - benzothiazole hybrids incorporate inhibitors of acetylcholinesterase (AChE), amyloid ß (Aß) aggregation and mitochondrial enzyme ABAD, whose interaction with Aß leads to mitochondrial dysfunction, into a single molecule. In vitro, several of 25 final compounds exerted excellent anti-AChE properties and interesting capabilities to block Aß aggregation. The best derivative of the series could be considered 10w that was found to be highly potent and selective towards AChE with the IC50 value in nanomolar range. Moreover, the same drug candidate exerted absolutely the best results of the series against ABAD, decreasing its activity by 23% at 100 µM concentration. Regarding the cytotoxicity profile of highlighted compound, it roughly matched that of its parent compound - 6-chlorotacrine. Finally, 10w was forwarded for in vivo scopolamine-induced amnesia experiment consisting of Morris Water Maze test, where it demonstrated mild procognitive effect. Taking into account all in vitro and in vivo data, highlighted derivative 10w could be considered as the lead structure worthy of further investigation.

Development of versatile and potent monoquaternary reactivators of acetylcholinesterase.

To date, the only treatments developed for poisoning by organophosphorus compounds, the most toxic chemical weapons of mass destruction, have exhibited limited efficacy and versatility. The available causal antidotes are based on reactivation of the enzyme acetylcholinesterase (AChE), which is rapidly and pseudo-irreversibly inhibited by these agents. In this study, we developed a novel series of monoquaternary reactivators combining permanently charged moieties tethered to position 6- of 3-hydroxypyridine-2-aldoxime reactivating subunit. Highlighted representatives (21, 24, and 27; also coded as K1371, K1374, and K1375, respectively) that contained 1-phenylisoquinolinium, 7-amino-1-phenylisoquinolinium and 4-carbamoylpyridinium moieties as peripheral anionic site ligands, respectively, showed efficacy superior or comparable to that of the clinically used standards. More importantly, these reactivators exhibited wide-spectrum efficacy and were minutely investigated via determination of their reactivation kinetics in parallel with molecular dynamics simulations to study their mechanisms of reactivation of the tabun-inhibited AChE conjugate. To further confirm the potential applicability of these candidates, a mouse in vivo assay was conducted. While K1375 had the lowest acute toxicity and the most suitable pharmacokinetic profile, the oxime K1374 with delayed elimination half-life was the most effective in ameliorating the signs of tabun toxicity. Moreover, both in vitro and in vivo, the versatility of the agents was substantially superior to that of clinically used standards. Their high efficacy and broad-spectrum capability make K1374 and K1375 promising candidates that should be further investigated for their potential as nerve agents and insecticide antidotes.

Amaryllidaceae Alkaloids of Norbelladine-Type as Inspiration for Development of Highly Selective Butyrylcholinesterase Inhibitors: Synthesis, Biological Activity Evaluation, and Docking Studies.

Alzheimer's disease (AD) is a multifactorial neurodegenerative condition of the central nervous system (CNS) that is currently treated by cholinesterase inhibitors and the N-methyl-d-aspartate receptor antagonist, memantine. Emerging evidence strongly supports the relevance of targeting butyrylcholinesterase (BuChE) in the more advanced stages of AD. Within this study, we have generated a pilot series of compounds (1-20) structurally inspired from belladine-type Amaryllidaceae alkaloids, namely carltonine A and B, and evaluated their acetylcholinesterase (AChE) and BuChE inhibition properties. Some of the compounds exhibited intriguing inhibition activity for human BuChE (hBuChE), with a preference for BuChE over AChE. Seven compounds were found to possess a hBuChE inhibition profile, with IC50 values below 1 µM. The most potent one, compound 6, showed nanomolar range activity with an IC50 value of 72 nM and an excellent selectivity pattern over AChE, reaching a selectivity index of almost 1400. Compound 6 was further studied by enzyme kinetics, along with in-silico techniques, to reveal the mode of inhibition. The prediction of CNS availability estimates that all the compounds in this survey can pass through the blood-brain barrier (BBB), as disclosed by the BBB score.

Synthesis of New Biscoumarin Derivatives, In Vitro Cholinesterase Inhibition, Molecular Modelling and Antiproliferative Effect in A549 Human Lung Carcinoma Cells.

A series of novel C4-C7-tethered biscoumarin derivatives (12a-e) linked through piperazine moiety was designed, synthesized, and evaluated biological/therapeutic potential. Biscoumarin 12d was found to be the most effective inhibitor of both acetylcholinesterase (AChE, IC50 = 6.30 µM) and butyrylcholinesterase (BChE, IC50 = 49 µM). Detailed molecular modelling studies compared the accommodation of ensaculin (well-established coumarin derivative tested in phase I of clinical trials) and 12d in the human recombinant AChE (hAChE) active site. The ability of novel compounds to cross the blood-brain barrier (BBB) was predicted with a positive outcome for compound 12e. The antiproliferative effects of newly synthesized biscoumarin derivatives were tested in vitro on human lung carcinoma cell line (A549) and normal colon fibroblast cell line (CCD-18Co). The effect of derivatives on cell proliferation was evaluated by MTT assay, quantification of cell numbers and viability, colony-forming assay, analysis of cell cycle distribution and mitotic activity. Intracellular localization of used derivatives in A549 cells was confirmed by confocal microscopy. Derivatives 12d and 12e showed significant antiproliferative activity in A549 cancer cells without a significant effect on normal CCD-18Co cells. The inhibition of hAChE/human recombinant BChE (hBChE), the antiproliferative activity on cancer cells, and the ability to cross the BBB suggest the high potential of biscoumarin derivatives. Beside the treatment of cancer, 12e might be applicable against disorders such as schizophrenia, and 12d could serve future development as therapeutic agents in the prevention and/or treatment of Alzheimer's disease.

Structure Elucidation and Cholinesterase Inhibition Activity of Two New Minor Amaryllidaceae Alkaloids.

Two new minor Amaryllidaceae alkaloids were isolated from Hippeastrum × hybridum cv. Ferrari and Narcissus pseudonarcissus cv. Carlton. The chemical structures were identified by various spectroscopic (one- and two-dimensional (1D and 2D) NMR, circular dichroism (CD), high-resolution mass spectrometry (HRMS) and by comparison with literature data of similar compounds. Both isolated alkaloids were screened for their human acetylcholinesterase (hAChE) and butyrylcholinesterase (hBuChE) inhibition activity. One of the new compounds, a heterodimer alkaloid of narcikachnine-type, named narciabduliine (2), showed balanced inhibition potency for both studied enzymes, with IC50 values of 3.29 ± 0.73 µM for hAChE and 3.44 ± 0.02 µM for hBuChE. The accommodation of 2 into the active sites of respective enzymes was predicted using molecular modeling simulation.

Aromatic Esters of the Crinane Amaryllidaceae Alkaloid Ambelline as Selective Inhibitors of Butyrylcholinesterase.

A total of 20 derivatives (1-20) of the crinane-type alkaloid ambelline were synthesized. These semisynthetic derivatives were assessed for their potency to inhibit both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). To predict central nervous system (CNS) availability, logBB was calculated, and the data correlated well with those obtained from the parallel artificial membrane permeability assay (PAMPA). All compounds should be able to permeate the blood-brain barrier (BBB) according to the obtained results. A total of 7 aromatic derivatives (5, 6, 7, 9, 10, 12, and 16) with different substitution patterns showed inhibitory potency against human serum BuChE (IC50 < 5 µM), highlighting the three top-ranked compounds as follows: 11-O-(1-naphthoyl)ambelline (16), 11-O-(2-methylbenzoyl)ambelline (6), and 11-O-(2-methoxybenzoyl)ambelline (9) with IC50 values of 0.10 ± 0.01, 0.28 ± 0.02, and 0.43 ± 0.04 µM, respectively. Notably, derivatives 6, 7, 9, and 16 displayed selective human BuChE (hBuChE) inhibition profiles with a selectivity index > 100. The in vitro results were supported by computational studies predicting plausible binding modes of the compounds in the active sites of hBuChE.

Functionalized aromatic esters of the Amaryllidaceae alkaloid haemanthamine and their in vitro and in silico biological activity connected to Alzheimer's disease.

A novel series of aromatic esters (1a-1m) related to the Amaryllidaceae alkaloid (AA) haemanthamine were designed, synthesized and tested in vitro with particular emphasis on the treatment of neurodegenerative diseases. Some of the synthesized compounds revealed promising acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory profile. Significant human AChE (hAChE) inhibition was demonstrated by 11-O-(3-nitrobenzoyl)haemanthamine (1j) with IC50value of 4.0 ± 0.3 µM. The strongest human BuChE (hBuChE) inhibition generated 1-O-(2-methoxybenzoyl)haemanthamine (1g) with IC50 value 3.3 ± 0.4 µM. Moreover, 11-O-(2-chlorbenzoyl)haemanthamine (1m) was able to inhibit both enzymes in dose-dependent manner. The mode of hAChE and hBuChE inhibition was minutely inspected using enzyme kinetic analysis in tandem with in silico experiments, the latter elucidating crucial interaction in 1j-, 1m-hAChE and 1g-, 1m-hBuChE complexes. The blood-brain barrier (BBB) permeability was investigated applying the parallel artificial membrane permeation assay (PAMPA) to predict the CNS availability of the compounds.

Interaction of Cucurbit[7]uril with Oxime K027, Atropine, and Paraoxon: Risky or Advantageous Delivery System?

Antidotes against organophosphates often possess physicochemical properties that mitigate their passage across the blood-brain barrier. Cucurbit[7]urils may be successfully used as a drug delivery system for bisquaternary oximes and improve central nervous system targeting. The main aim of these studies was to elucidate the relationship between cucurbit[7]uril, oxime K027, atropine, and paraoxon to define potential risks or advantages of this delivery system in a complex in vivo system. For this reason, in silico (molecular docking combined with umbrella sampling simulation) and in vivo (UHPLC-pharmacokinetics, toxicokinetics; acetylcholinesterase reactivation and functional observatory battery) methods were used. Based on our results, cucurbit[7]urils affect multiple factors in organophosphates poisoning and its therapy by (i) scavenging paraoxon and preventing free fraction of this toxin from entering the brain, (ii) enhancing the availability of atropine in the central nervous system and by (iii) increasing oxime passage into the brain. In conclusion, using cucurbit[7]urils with oximes might positively impact the overall treatment effectiveness and the benefits can outweigh the potential risks.

Substituted Piperazines as Novel Potential Radioprotective Agents.

The increasing risk of radiation exposure underlines the need for novel radioprotective agents. Hence, a series of novel 1-(2-hydroxyethyl)piperazine derivatives were designed and synthesized. Some of the compounds protected human cells against radiation-induced apoptosis and exhibited low cytotoxicity. Compared to the previous series of piperazine derivatives, compound 8 exhibited a radioprotective effect on cell survival in vitro and low toxicity in vivo. It also enhanced the survival of mice 30 days after whole-body irradiation (although this increase was not statistically significant). Taken together, our in vitro and in vivo data indicate that some of our compounds are valuable for further research as potential radioprotectors.

Isoquinoline Alkaloids from Berberis vulgaris as Potential Lead Compounds for the Treatment of Alzheimer's Disease.

Three new alkaloids, bersavine (3), muraricine (4), and berbostrejdine (8), together with seven known isoquinoline alkaloids (1-2, 5-7, 9, and 10) were isolated from an alkaloidal extract of the root bark of Berberis vulgaris. The structures of the isolated compounds were determined by spectroscopic methods, including 1D and 2D NMR techniques, HRMS, and optical rotation, and by comparison of the obtained data with those in the literature. The NMR data of berbamine (5), aromoline (6), and obamegine (7) were completely assigned employing 2D NMR experiments. Alkaloids isolated in sufficient amounts were evaluated for their in vitro acetylcholinesterase, butyrylcholinesterase (BuChE), prolyl oligopeptidase, and glycogen synthase kinase-3ß inhibitory activities. Selected compounds were studied for their ability to permeate through the blood-brain barrier. Significant human BuChE ( hBuChE) inhibitory activity was demonstrated by 6 (IC50 = 0.82 ± 0.10 µM). The in vitro data were further supported by computational analysis that showed the accommodation of 6 in the active site of hBuChE.

Novel quinazolin-4-one derivatives as potentiating agents of doxorubicin cytotoxicity.

We report the design, synthesis and biological evaluation of 17 novel 8-aryl-2-morpholino-3,4-dihydroquinazoline derivatives based on the standard model of DNA-PK and PI3K inhibitors. Novel compounds are sub-divided into two series where the second series of five derivatives was designed to have a better solubility profile over the first one. A combination of in vitro and in silico techniques suggested a plausible synergistic effect with doxorubicin of the most potent compound 14d on cell proliferation via DNA-PK and poly(ADP-ribose) polymerase-1 (PARP-1) inhibition, while alone having a negligible effect on cell proliferation.

The number and phenotype of myocardial and adipose tissue CD68+ cells is associated with cardiovascular and metabolic disease in heart surgery patients.

BACKGROUND AND AIMS: CD68+ cells are a potent source of inflammatory cytokines in adipose tissue and myocardium. The development of low-grade inflammation in adipose tissue is implicated in the pathogenesis of obesity-associated disorders including type 2 diabetes mellitus (T2DM) and cardiovascular disease. The main aim of the study was to characterize and quantify myocardial and adipose tissue CD68+ cells and adipose tissue crown-like structures (CLS) in patients with obesity, coronary artery disease (CAD) and T2DM. METHODS AND RESULTS: Samples were obtained from the right atrium, epicardial (EAT) and subcutaneous adipose tissue (SAT) during elective heart surgery (non-obese, n = 34 patients; obese, n = 24 patients). Immunohistochemistry was used to visualize CD68+ cells. M1-polarized macrophages were visualized by immunohistochemical detection of CD11c. The proportion of CD68+ cells was higher in EAT than in SAT (43.4 ± 25.0 versus 32.5 ± 23.1 cells per 1 mm2; p = 0.015). Myocardial CD68+ cells were more abundant in obese patients (45.6 ± 24.5 versus 27.7 ± 14.8 cells per 1 mm2; p = 0.045). In SAT, CD68+ cells were more frequent in CAD patients (37.3 ± 23.0 versus 23.1 ± 20.9 cells per 1 mm2; p = 0.012). Patients having CLS in their SAT had higher average BMI (34.1 ± 6.4 versus 29.0 ± 4.5; p = 0.024). CONCLUSIONS: Regional-based increases in the frequency of CD68+ cells and changes of their phenotype in CLS were detected in obese patients and CAD patients. Therapeutic modulation of adipose tissue inflammation may represent a target for treatment of obesity.

Oxime K203: a drug candidate for the treatment of tabun intoxication.

For over 60 years, researchers across the world have sought to deal with poisoning by nerve agents, the most toxic and lethal chemical weapons. To date, there is no efficient causal antidote with sufficient effect. Every trialed compound fails to fulfil one or more criteria (e.g. reactivation potency, broad reactivation profile). In this recent contribution, we focused our attention to one of the promising compounds, namely the bis-pyridinium reactivator K203. The oxime K203 is very often cited as the best reactivator against tabun poisoning. Herein, we provide all the available literature data in comprehensive and critical review to address whether K203 could be considered as a new drug candidate against organophosphorus poisoning with the stress on tabun. We describe its development from the historical point of view and review all available in vitro as well as in vivo data to date. K203 is easily accessible by a relatively simple two-step synthesis. It is well accommodated in the enzyme active gorge of acetylcholinesterase providing suitable interactions for reactivation, as shown by molecular docking simulations. According to a literature survey, in vitro data for tabun-inhibited AChE are extraordinary. However, in vivo efficiency remains unconvincing. The K203 toxicity profile did not show any perturbations compared to clinically used standards; on the other hand versatility of K203 does not exceed currently available oximes. In summary, K203 does not seem to address current issues associated with the organophosphorus poisoning, especially the broad profile against all nerve agents. However, its reviewed efficacy entitles K203 to be considered as a backup or tentative replacement for obidoxime and trimedoxime, currently only available anti-tabun drugs.

Coronary Artery Disease Is Associated with an Increased Amount of T Lymphocytes in Human Epicardial Adipose Tissue.

Immunocompetent cells including lymphocytes play a key role in the development of adipose tissue inflammation and obesity-related cardiovascular complications. The aim of the study was to explore the relationship between epicardial adipose tissue lymphocytes and coronary artery disease (CAD). To this end, we studied the content and phenotype of lymphocytes in peripheral blood, subcutaneous adipose tissue (SAT), and epicardial adipose tissue (EAT) in subjects with and without CAD undergoing elective cardiac surgery. Eleven subjects without CAD (non-CAD group) and 22 age-, BMI-, and HbA1C-matched individuals with CAD were included into the study. Blood, SAT, and EAT samples were obtained at the beginning of surgery. Lymphocyte populations were quantified as % of CD45+ cells using flow cytometry. Subjects with CAD had a higher total lymphocyte amount in EAT compared with SAT (32.24 ± 7.45 vs. 11.22 ± 1.34%, p = 0.025) with a similar trend observed in non-CAD subjects (29.68 ± 7.61 vs. 10.13 ± 2.01%, p = 0.067). T (CD3+) cells were increased (75.33 ± 2.18 vs. 65.24 ± 4.49%, p = 0.032) and CD3- cells decreased (21.17 ± 2.26 vs. 31.64 ± 4.40%, p = 0.028) in EAT of CAD relative to the non-CAD group. In both groups, EAT showed an elevated percentage of B cells (5.22 ± 2.43 vs. 0.96 ± 0.21%, p = 0.039 for CAD and 12.49 ± 5.83 vs. 1.16 ± 0.19%, p = 0.016 for non-CAD) and reduced natural killer (NK) cells (5.96 ± 1.32 vs. 13.22 ± 2.10%, p = 0.012 for CAD and 5.32 ± 1.97 vs. 13.81 ± 2.72%, p = 0.022 for non-CAD) relative to SAT. In conclusion, epicardial adipose tissue in subjects with CAD shows an increased amount of T lymphocytes relative to non-CAD individuals as well as a higher number of total and B lymphocytes and reduced NK cells as compared with corresponding SAT. These changes could contribute to the development of local inflammation and coronary atherosclerosis.