Interaction of ethanol and tetrahydro-beta-carboline (THBC) in a discriminative task

Psycho-Neuro-EndocrinE-Immunology Therapy of Cancer, Autoimmunity, Geriatric Disorders, Covid-19, and Hypertension

Despite the great number of experimental investigations in the area of psycho-neuro-endocrine-immunology showing that endocrine, nervous, and immune systems cannot be in vivo physiologically separated, the diagnosis and therapies of the pathologies of these three functional biological systems continue to be separately performed from a clinical practice point of view. The separation between experimental and clinical medicine became dramatic after the discovery of more than 10 human molecules provided by anti-inflammatory and antitumor activity, completely devoid of any toxicity, which may be subdivided into three fundamental classes, consisting of the pineal indole, beta-carboline, and methoxy-kynuramine hormones. Moreover, human systemic diseases, including cancer, autoimmunity, and cardiovascular pathologies, despite their different pathogenesis and symptomatology, are commonly characterized by a progressive decline in the endogenous production of pineal hormones, endocannabinoids, and Ang 1-7, with a consequent inflammatory status and diminished natural resistance against cancer. Then the evaluation of the functional status of the pineal gland, the endocannabinoid system, and ACE2-Ang 1-7 axis should have to be included within the laboratory analyses for the systemic diseases. Finally, the correction of cancer- and autoimmunity-related neuroimmune and neuroendocrine alterations could influence the clinical course of systemic diseases. In fact, preliminary clinical results would demonstrate that the neuroimmune regimen with pineal hormones, cannabinoids, and Ang 1-7 may allow clinical benefits also in patients affected by systemic pathologies, including cancer, autoimmunity, and cardiovascular diseases, who did not respond to the standard therapies.

Structural insight into Marburg virus nucleoprotein-RNA complex formation

The nucleoprotein (NP) of Marburg virus (MARV), a close relative of Ebola virus (EBOV), encapsidates the single-stranded, negative-sense viral genomic RNA (vRNA) to form the helical NP-RNA complex. The NP-RNA complex constitutes the core structure for the assembly of the nucleocapsid that is responsible for viral RNA synthesis. Although appropriate interactions among NPs and RNA are required for the formation of nucleocapsid, the structural basis of the helical assembly remains largely elusive. Here, we show the structure of the MARV NP-RNA complex determined using cryo-electron microscopy at a resolution of 3.1 Å. The structures of the asymmetric unit, a complex of an NP and six RNA nucleotides, was very similar to that of EBOV, suggesting that both viruses share common mechanisms for the nucleocapsid formation. Structure-based mutational analysis of both MARV and EBOV NPs identified key residues for helical assembly and subsequent viral RNA synthesis. Importantly, most of the residues identified were conserved in both viruses. These findings provide a structural basis for understanding the nucleocapsid formation and contribute to the development of novel antivirals against MARV and EBOV.

Discriminative stimulus effects of ethanol: neuropharmacological characterization

Generally, compounds discriminated by animals possess psychotropic effects in animals and humans. As with many other drugs of abuse, strength of the ethanol discriminative stimulus is dose related. The majority of studies show that doses close to 1.0 g/kg are close to the minimum at which the discrimination can be learned easily. Substitution studies suggest that anxiolytic, sedative, atactic, and myorelaxant effects of ethanol all play an important role in the formation of its intercoeptive stimulus. Low doses of ethanol produce more excitatory cues, similar to amphetamine-like subjective stimuli, whereas higher doses produce rather sedative/hypnotic stimuli similar to those elicited by barbiturates. Substitution studies have shown that the complete substitution for ethanol may be exerted by certain GABA-mimetic drugs acting through different sites within the GABA(A)-benzodiazepine receptor complex (e.g., diazepam, pentobarbital, certain neurosteroids), gamma-hydroxybutyrate, and antagonists of the glutamate NMDA receptor. Among the NMDA receptor antagonists both noncompetitive (e.g., dizocilpine) and competitive antagonists (e.g., CGP 40116) are capable of substituting for ethanol. Further, some antagonists of strychnine-insensitive glycine modulatory sites among the NMDA receptor complex (e.g., L-701,324) dose-dependently substitute for the ethanol discriminative stimulus. On the other hand, neither GABA-benzodiazepine antagonists nor NMDA receptor agonists produce contradictory effects (i.e., reduce the ethanol discriminative stimulus). There is influence of a particular training dose of ethanol on the substitution pattern of different compounds. For example, 5-HT(1B/2C) agonists substitute for intermediate (1.0 g/kg) but not higher (2.0 g/kg) ethanol training doses. Discrimination studies with ethanol and drugs acting on NMDA and GABA receptors consistently indicate asymmetrical generalization. For example, ethanol is able to generalize to barbiturates and benzodiazepines, but neither the benzodiazepine nor barbiturate response generalizes to ethanol. Only a few drugs are able to antagonize, at least to some extent, the discriminative stimulus of ethanol (e.g., partial inverse GABA-benzodiazepine receptor antagonist Ro 15-4513 and the opioid antagonist naloxone). The ethanol stimulus effect may be increased (i.e., stronger recognition) by N-cholinergic drugs (nicotine), dopaminergic drugs (apomorphine), and 5-HT3 receptor agonists (m-chlorophenylbiguanide). Thus, the ethanol stimulus is composed of the several components, with the NMDA receptor and GABA(A) receptor complex being of particular importance. This suggests that a drug mixture may be more capable of substituting for ethanol (or block its stimulus) than a single compound. The ability of drugs to substitute for the ethanol discriminative stimulus is frequently, although not preclusively, associated with the reduction of voluntary ethanol consumption. The examples of positive correlation are gamma-hydroxybutyrate, possibly memantine and certain serotonergic drugs such as fluoxetine. However, it remains uncertain to what extent the discriminative stimulus of ethanol can be seen as relevant in the understanding of the complex mechanisms of dependence.

Gas chromatographic-mass spectrometric screening procedure for the identification of formaldehyde-derived tetrahydro-beta-carbolines in human urine

A gas chromatographic-mass spectrometric method for the identification of 1,2,3,4-tetrahydro-beta-carboline and four metabolites extracted from urine is described. In a first step the substances, formed by reaction of formaldehyde with biogenic amines, were derivatized in aqueous solution with methyl chloroformate to eliminate an artificial formation of these compounds via condensation of endogenous indole ethylamines with aldehydes or alpha-keto acids during the work-up procedure. This initial derivatization formed stable hydrophobic compounds and improved the extractability for a liquid-liquid extraction. Further clean-up was performed by solid-phase extraction on C18 sample preparation columns. The method can identify these compounds in the picogram range.