Some aspects of the pharmacology of an homologous series of choline esters of fatty acids

High-dimensional proteomics identifies organ injury patterns associated with outcomes in human trauma

INTRODUCTION

Severe traumatic injury with shock can lead to direct and indirect organ injury; however, tissue-specific biomarkers are limited in clinical panels. We used proteomic and metabolomic databases to identify organ injury patterns after severe injury in humans.

METHODS

Plasma samples (times 0, 24, and 72 hours after arrival to trauma center) from injured patients enrolled in two randomized prehospital trials were subjected to multiplexed proteomics (SomaLogic Inc., Boulder, CO). Patients were categorized by outcome: nonresolvers (died >72 hours or required ≥7 days of critical care), resolvers (survived to 30 days and required <7 days of critical care), and low Injury Severity Score (ISS) controls. Established tissue-specific biomarkers were identified through a literature review and cross-referenced with tissue specificity from the Human Protein Atlas. Untargeted plasma metabolomics (Metabolon Inc., Durham, NC), inflammatory mediators, and endothelial damage markers were correlated with injury biomarkers. Kruskal-Wallis/Mann-Whitney U tests with false discovery rate correction assessed differences in biomarker expression across outcome groups (significance; p < 0.1).

RESULTS

Of 142 patients, 78 were nonresolvers (median ISS, 30), 34 were resolvers (median ISS, 22), and 30 were low ISS controls (median ISS, 1). A broad release of tissue-specific damage markers was observed at admission; this was greater in nonresolvers. By 72 hours, nine cardiac, three liver, eight neurologic, and three pulmonary proteins remained significantly elevated in nonresolvers compared with resolvers. Cardiac damage biomarkers showed the greatest elevations at 72 hours in nonresolvers and had significant positive correlations with proinflammatory mediators and endothelial damage markers. Nonresolvers had lower concentrations of fatty acid metabolites compared with resolvers, particularly acyl carnitines and cholines.

CONCLUSION

We identified an immediate release of tissue-specific biomarkers with sustained elevation in the liver, pulmonary, neurologic, and especially cardiac injury biomarkers in patients with complex clinical courses after severe injury. The persistent myocardial injury in nonresolvers may be due to a combination of factors including metabolic stress, inflammation, and endotheliopathy.

Metabolomic response to collegiate football participation: Pre- and Post-season analysis

Contact sports participation has been shown to have both beneficial and detrimental effects on health, however little is known about the metabolic sequelae of these effects. We aimed to identify metabolite alterations across a collegiate American football season. Serum was collected from 23 male collegiate football athletes before the athletic season (Pre) and after the last game (Post). Samples underwent nontargeted metabolomic profiling and 1131 metabolites were included for univariate, pathway enrichment, and multivariate analyses. Significant metabolites were assessed against head acceleration events (HAEs). 200 metabolites changed from Pre to Post (P < 0.05 and Q < 0.05); 160 had known identity and mapped to one of 57 pre-defined biological pathways. There was significant enrichment of metabolites belonging to five pathways (P < 0.05): xanthine, fatty acid (acyl choline), medium chain fatty acid, primary bile acid, and glycolysis, gluconeogenesis, and pyruvate metabolism. A set of 12 metabolites was sufficient to discriminate Pre from Post status, and changes in 64 of the 200 metabolites were also associated with HAEs (P < 0.05). In summary, the identified metabolites, and candidate pathways, argue there are metabolic consequences of both physical training and head impacts with football participation. These findings additionally identify a potential set of objective biomarkers of repetitive head injury.

Long-Chain Acylcholines Link Butyrylcholinesterase to Regulation of Non-neuronal Cholinergic Signaling

Acylcholines are comprised of an acyl chain esterified to a choline moiety; acetylcholine is the best-characterized member of this class, functioning as a neurotransmitter in the central and peripheral nervous systems as well as an inhibitor of cytokine production by macrophages and other innate immune cells. Acylcholines are metabolized by a class of cholinesterases, including acetylcholinesterase (a specific regulator of acetylcholine levels) and butyrylcholinesterase (BChE, an enigmatic enzyme whose function has not been resolved by genetic knockout models). BChE provides reserve capacity to hydrolyze acetylcholine, but its importance is arguable given acetylcholinesterase is the most catalytically efficient enzyme characterized to date. While known to be substrates of BChE in vitro, endogenous production of long-chain acylcholines is a recent discovery enabled by untargeted metabolomics. Compared to acetylcholine, long-chain acylcholines show greater stability in circulation with homeostatic levels-dictated by synthesis and clearance-suggested to impact cholinergic receptor sensitivity of acetylcholine with varying levels of antagonism. Acylcholines then provide a link between BChE and non-neuronal acetylcholine signaling, filling a gap in understanding around how imbalances between acylcholines and BChE could modulate inflammatory disease, such as the "cytokine storm" identified in severe COVID-19. Areas for further research, development, and clinical testing are outlined.

Comprehensive Circulatory Metabolomics in ME/CFS Reveals Disrupted Metabolism of Acyl Lipids and Steroids

The latest worldwide prevalence rate projects that over 65 million patients suffer from myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), an illness with known effects on the functioning of the immune and nervous systems. We performed an extensive metabolomics analysis on the plasma of 52 female subjects, equally sampled between controls and ME/CFS patients, which delivered data for about 1750 blood compounds spanning 20 super-pathways, subdivided into 113 sub-pathways. Statistical analysis combined with pathway enrichment analysis points to a few disrupted metabolic pathways containing many unexplored compounds. The most intriguing finding concerns acyl cholines, belonging to the fatty acid metabolism sub-pathway of lipids, for which all compounds are consistently reduced in two distinct ME/CFS patient cohorts. We compiled the extremely limited knowledge about these compounds and regard them as promising in the quest to explain many of the ME/CFS symptoms. Another class of lipids with far-reaching activity on virtually all organ systems are steroids; androgenic, progestin, and corticosteroids are broadly reduced in our patient cohort. We also report on lower dipeptides and elevated sphingolipids abundance in patients compared to controls. Disturbances in the metabolism of many of these molecules can be linked to the profound organ system symptoms endured by ME/CFS patients.

Comblike Ionic Complexes of Hyaluronic Acid and Alkanoylcholine Surfactants as a Platform for Drug Delivery Systems

Nontoxic alkanoylcholine soaps ( nACh) were synthesized from choline and fatty acids with numbers of carbons n equal to 12, 14, 16, and 18, the latter including both saturated and 9- cis unsaturated alkanoyl chains. Coupling of nACh with hyaluronic acid (HyA) rendered comblike ionic complexes nACh·HyA that were non-water-soluble. The complexes were thermally stable up to temperatures above 200 °C but readily degraded by water, in particular when hyaluronidases were present in the aqueous medium. In the solid state, these complexes were self-assembled in a biphasic layered structure in which the surfactant and the polysaccharide phases were alternating regularly with a periodicity dependent on the length of the alkanoyl chain. The paraffinic phase was found to be crystallized in saturated complexes with n ≥ 14, but only 18ACh·HyA showed reversible melting crystallization when subjected to cyclic heating-cooling treatment. Nanoparticles with diameters in the 50-150 nm range were prepared by ionotropic gelation from unbalanced 18ACh·HyA complexes with surfactant:HyA ratios of 0.5 and 0.25. These nanoparticles were also structured in layers, swelled slowly in water, and shown to be noncytotoxic in in vitro assays against macrophages cells. It was also shown that the anticancer drug doxorubicin was efficiently encapsulated in both films and NPs of 18ACh·HyA, and its release was shown to be almost linear and complete after one day of incubation in physiological medium. The nACh·HyA complexes constitute a highly promising biocompatible/biodegradable platform for the design of systems suitable for drug transport and targeting delivery in anticancer chemotherapy.

Cholinomimetic teratogens: studies with chicken embryos

The cholinomimetic compounds carbachol, decamethonium, neostigmine, succinylcholine, trimethylphenylammonium, and others were tested for their interference with normal chick development. All these compounds led to abnormalities of the cervical vertebrae; at higher dosage interference with normal morphogenesis involved the whole vertebral column. Hypoplasia of the leg muscles occurred with lower incidence. Responses, tested with carbachol, rose from 24 to 72 and 96 h, then declined to 120 h of incubation. Two of the cholinometic compounds used in combined treatment produced a high degree of synergism. Gallamine, benzoquinomium, butyrylcholine, and bethanechol had protective effects. Acetylcholine, at high dosage, caused defects different from the above. It is suggested that the cholinomimetic teratogens interfere with normal development by displacing acetylcholine from its receptors or by forming complexes with it.