5-HT2A Receptor Knockout Mice Show Sex-Dependent Differences following Acute Noribogaine Administration.

Noribogaine (noribo) is the primary metabolite from ibogaine, an atypical psychedelic alkaloid isolated from the root bark of the African shrub Tabernanthe iboga. The main objective of this study was to test the hypothesis that molecular, electrophysiological, and behavioral responses of noribo are mediated by the 5-HT2A receptor (5-HT2AR) in mice. In that regard, we used male and female, 5-HT2AR knockout (KO) and wild type (WT) mice injected with a single noribo dose (10 or 40 mg/kg; i.p.). After 30 min., locomotor activity was recorded followed by mRNA measurements by qPCR (immediate early genes; IEG, glutamate receptors, and 5-HT2AR levels) and electrophysiology recordings of layer V pyramidal neurons from the medial prefrontal cortex. Noribo 40 decreased locomotion in male, but not female WT. Sex and genotype differences were observed for IEG and glutamate receptor expression. Expression of 5-HT2AR mRNA increased in the mPFC of WT mice following Noribo 10 (males) or Noribo 40 (females). Patch-clamp recordings showed that Noribo 40 reduced the NMDA-mediated postsynaptic current density in mPFC pyramidal neurons only in male WT mice, but no effects were found for either KO males or females. Our results highlight that noribo produces sexually dimorphic effects while the genetic removal of 5HT2AR blunted noribo-mediated responses to NMDA synaptic transmission.

Reactivity of the Iboga Skeleton: Oxidation Study of Ibogaine and Voacangine.

The iboga alkaloids scaffold shows great potential as a pharmacophore in drug candidates for the treatment of neuropsychiatric disorders. Thus, the study of the reactivity of this type of motif is particularly useful for the generation of new analogs suitable for medicinal chemistry goals. In this article, we analyzed the oxidation pattern of ibogaine and voacangine using dioxygen, peroxo compounds, and iodine as oxidizing agents. Special focus was placed on the study of the regio- and stereochemistry of the oxidation processes according to the oxidative agent and starting material. We found that the C16-carboxymethyl ester present in voacangine stabilizes the whole molecule toward oxidation in comparison to ibogaine, especially in the indole ring, where 7-hydroxy- or 7-peroxy-indolenines can be obtained as oxidation products. Nevertheless, the ester moiety enhances the reactivity of the isoquinuclidinic nitrogen to afford C3-oxidized products through a regioselective iminium formation. This differential reactivity between ibogaine and voacangine was rationalized using computational DFT calculations. In addition, using qualitative and quantitative NMR experiments combined with theoretical calculations, the absolute stereochemistry at C7 in the 7-hydroxyindolenine of voacangine was revised to be S, which corrects previous reports proposing an R configuration.

Iboga Inspired N-Indolylethyl-Substituted Isoquinuclidines as a Bioactive Scaffold: Chemoenzymatic Synthesis and Characterization as GDNF Releasers and Antitrypanosoma Agents.

The first stage of the drug discovery process involves the identification of small compounds with biological activity. Iboga alkaloids are monoterpene indole alkaloids (MIAs) containing a fused isoquinuclidine-tetrahydroazepine ring. Both the natural products and the iboga-inspired synthetic analogs have shown a wide variety of biological activities. Herein, we describe the chemoenzymatic preparation of a small library of novel N-indolylethyl-substituted isoquinuclidines as iboga-inspired compounds, using toluene as a starting material and an imine Diels-Alder reaction as the key step in the synthesis. The new iboga series was investigated for its potential to promote the release of glial cell line-derived neurotrophic factor (GDNF) by C6 glioma cells, and to inhibit the growth of infective trypanosomes. GDNF is a neurotrophic factor widely recognized by its crucial role in development, survival, maintenance, and protection of dopaminergic neuronal circuitries affected in several neurological and psychiatric pathologies. Four compounds of the series showed promising activity as GDNF releasers, and a leading structure (compound 11) was identified for further studies. The same four compounds impaired the growth of bloodstream Trypanosoma brucei brucei (EC50 1-8 µM) and two of them (compounds 6 and 14) showed a good selectivity index.

TBL1XR1 associated intellectual disability, a new missense variant with dysmorphic features plus autism: Expanding the phenotypic spectrum.

Missense and frameshift pathogenic variants and microdeletions involving TBL1XR1 gene have been described in patients with intellectual disability, autism, Rett-like features and schizophrenia, some of them with the clinical diagnosis of Pierpont syndrome, a rare pattern of multiple congenital anomalies, but others without dysmorphic findings or with non-specific ones, and also patients with only some of the features associated with Pierpont syndrome. We here present a case with a de novo novel missense variant in TBL1XR1 gene with overlapping features with Pierpont syndrome and autism, a neurobehavioral manifestation not previously reported in Pierpont syndrome. This patient expands the phenotypic spectrum of TBL1XR1 gene pathogenic variants.

C-H Amination via Nitrene Transfer Catalyzed by Mononuclear Non-Heme Iron-Dependent Enzymes.

Expanding the reaction scope of natural metalloenzymes can provide new opportunities for biocatalysis. Mononuclear non-heme iron-dependent enzymes represent a large class of biological catalysts involved in the biosynthesis of natural products and catabolism of xenobiotics, among other processes. Here, we report that several members of this enzyme family, including Rieske dioxygenases as well as α-ketoglutarate-dependent dioxygenases and halogenases, are able to catalyze the intramolecular C-H amination of a sulfonyl azide substrate, thereby exhibiting a promiscuous nitrene transfer reactivity. One of these enzymes, naphthalene dioxygenase (NDO), was further engineered resulting in several active site variants that function as C-H aminases. Furthermore, this enzyme could be applied to execute this non-native transformation on a gram scale in a bioreactor, thus demonstrating its potential for synthetic applications. These studies highlight the functional versatility of non-heme iron-dependent enzymes and pave the way to their further investigation and development as promising biocatalysts for non-native metal-catalyzed transformations.

Toluene Dioxygenase-Catalysed Oxidation of Benzyl Azide to Benzonitrile: Mechanistic Insights for an Unprecedented Enzymatic Transformation.

Enzymatic dioxygenation of benzyl azide by toluene dioxygenase (TDO) produces significant amounts of the cis-cyclohexadienediol derived from benzonitrile, along with the expected azido diols. We demonstrate that TDO catalyses the oxidation of benzyl azide to benzonitrile, which is further dioxygenated to produce the observed cis-diol. A proposed mechanism for this transformation involves initial benzylic monooxygenation followed by a nitrene-mediated rearrangement to form an oxime, which is further dehydrated to afford the nitrile. To the best of our knowledge, this is the first report of enzymatic oxidation of an alkyl azide to a nitrile. In addition, the described oxime-dehydration activity has not been reported for Rieske dioxygenases.

Microdeletions of the 7q32.2 imprinted region are associated with Silver-Russell syndrome features.

The association of maternal uniparental disomy of human chromosome 7 (upd(7) mat) and the growth retardation disorder Silver-Russell syndrome (SRS) is well established, but the causative gene or region is currently unknown. However, several observations indicate that molecular alterations of the genomically imprinted MEST region in 7q32.2 are associated with growth retardation and a phenotype reminiscent to SRS. We now report on a second patient with a similar phenotype and a de novo 7q32.2 microdeletion including MEST affecting the paternal allele. This confirms the central role of imprinted genes in 7q32.2 in the etiology of a growth retardation phenotype associated with SRS features.

Deletion 1q43-44 in a patient with clinical diagnosis of Warburg-Micro syndrome.

Warburg-Micro syndrome (WARBM) is an autosomal recessive syndrome characterized by microcephaly, microphthalmia, microcornea, congenital cataracts, optic atrophy and central nervous system malformations. This syndrome is caused by mutations in the RAB3GAP1/2 and RAB18 genes, part of the Rab family, and in the TBC1D20 gene, which contributes to lipid droplet formation/metabolism. Here we present a patient with clinical diagnosis of WARBM syndrome, who did not have mutations in either the RAB3GAP1/2 genes, in the main exons of RAB18, nor in the TBC1D20 gene. However, the analysis with CGH-array detected a 9.6 Mb deletion at 1q43-qter. We performed a genotype-phenotype correlation using 20 previously published patients in whom the coordinates of the deleted regions were defined. The comparative analysis revealed that the current patient and three of the other 20 patients share the loss of six genes, four of which are related with the family of G proteins, and are strongly expressed in the brain, retina, heart and kidney. Consequently, their haploinsufficiency may result in different combinations of clinical alterations, including some of those of WARBM syndrome. In addition, the haploinsufficiency of other genes may contribute to other defects and clinical variability. Additionally, for the genotype-phenotype correlation, one must also consider molecular pathways that can result in the observed alterations. To early confirm a genetic diagnosis is essential for the patient and family. The current patient was considered as having a recessive syndrome, but since he had a "de novo" deletion, there was not an increased recurrence risk.

Noribogaine acute administration in rats promotes wakefulness and suppresses REM sleep.

Ibogaine is a potent atypical psychedelic that has gained considerable attention due to its antiaddictive and antidepressant properties in preclinical and clinical studies. Previous research from our group showed that ibogaine suppresses sleep and produces an altered wakefulness state, which resembles natural REM sleep. However, after systemic administration, ibogaine is rapidly metabolized to noribogaine, which also shows antiaddictive effects but with a distinct pharmacological profile, making this drug a promising therapeutic candidate. Therefore, we still ignore whether the sleep/wake alterations depend on ibogaine or its principal metabolite noribogaine. To answer this question, we conducted polysomnographic recordings in rats following the administration of pure noribogaine. Our results show that noribogaine promotes wakefulness while reducing slow-wave sleep and blocking REM sleep, similar to our previous results reported for ibogaine administration. Thus, we shed new evidence on the mechanisms by which iboga alkaloids work in the brain.

Ayahuasca Ritual, Personality and Sociality: Observational Research Conducted in a Substance Use Disorder Rehabilitation Center in Uruguay.

The current article presents a mixed qualitative-quantitative observational study of the effect of ayahuasca ritual on subjective experiences and personality traits on participants of a center specialized in the treatment of substance use disorder in Uruguay. When comparing the psychological traits of ayahuasca participants to a control group, quantitative results using the Zuckerman-Kuhlman-Aluja Personality Questionnaire showed statistically significant higher scores in Impulsive Sensation Seeking, Boredom Susceptibility, and Social Warmth scales. Qualitative analysis of ayahuasca experiences resulted in five main categories: emotional experiences (including social emotions such as love and empathy), corporal experiences, spiritual/transcendental experiences, personal experiences, and visions. Last, qualitative descriptions provide support for the importance of social interactions in the phenomenological manifestations of the psychedelic experience. Both quantitative and qualitative results suggest that the combination of social interactions and the pharmacological action of ayahuasca could facilitate the manifestation of social emotions during the ritual, and may contribute to the long-term increase of empathic and social aspects of personality.

Ayahuasca, Personality and Acute Psychological Effects in Neo-Shamanic and Religious Settings in Uruguay.

This study is an interdisciplinary research into Uruguayan ayahuasca users belonging to one neo-shamanic and one Santo Daime group. The study involved the chemical analysis of ayahuasca samples, an ethnographic description of the two traditions and rituals, and the application of psychometric scales to measure personality differences, and the acute psychological effects during an ayahuasca ritual. Personality measurements showed lower scores for Santo Daime in Neuroticism-Anxiety, Dependence, Low Self-Esteem, Anger and Restlessness. These differences may be related to the presence of participants under treatment in the neo-shamanic group and/or to the protective effects of a church religion such as Santo Daime. Regarding acute effects, the neo-shamanic group showed higher scores in Somesthesia and Perception, which can be related to the high-arousal ritual setting. Chemical analysis for the ayahuasca samples showed a typical composition of alkaloids. No adulterants were found. The sample from the neo-shamanic group displayed a higher ß-carbolines:DMT ratio compared to the Santo Daime sample, which could be related to the higher effects observed for Somesthesia for the neo-shamanic group. Significant positive correlations between some personality traits and acute effects were found only in the neo-shamanic group, which may be related to the more individualistic approach of this tradition.

Functionalization of breast implants by cyclodextrin in-situ polymerization: a local drug delivery system for augmentation mammaplasty.

Mammaplasty is a widely performed surgical procedure worldwide, utilized for breast reconstruction, in the context of breast cancer treatment, and aesthetic purposes. To enhance post-operative outcomes and reduce risks (hematoma with required evacuation, capsular contracture, implant-associated infection and others), the controlled release of medicaments can be achieved using drug delivery systems based on cyclodextrins (CDs). In this study, our objective was to functionalize commercially available silicone breast implants with smooth and textured surfaces through in-situ polymerization of two CDs: ß-CD/citric acid and 2-hydroxypropyl-ß-CD/citric acid. This functionalization serves as a local drug delivery system for the controlled release of therapeutic molecules that potentially can be a preventive treatment for post-operative complications in mammaplasty interventions. Initially, we evaluated the pre-treatment of sample surfaces with O2 plasma, followed by chitosan grafting. Subsequently, in-situ polymerization using both types of CDs was performed on implants. The results demonstrated that the proposed pre-treatment significantly increased the polymerization yield. The functionalized samples were characterized using microscopic and physicochemical techniques. To evaluate the efficacy of the proposed system for controlled drug delivery in augmentation mammaplasty, three different molecules were utilized: pirfenidone (PFD) for capsular contracture prevention, Rose Bengal (RB) as anticancer agent, and KR-12 peptide (KR-12) to prevent bacterial infection. The release kinetics of PFD, RB, and KR-12 were analyzed using the Korsmeyer-Peppas and monolithic solution mathematical models to identify the respective delivery mechanisms. The antibacterial effect of KR-12 was assessed against Staphylococcus epidermidis and Pseudomonas aeruginosa, revealing that the antibacterial rate of functionalized samples loaded with KR-12 was dependent on the diffusion coefficients. Finally, due to the immunomodulatory properties of KR-12 peptide on epithelial cells, this type of cells was employed to investigate the cytotoxicity of the functionalized samples. These assays confirmed the superior properties of functionalized samples compared to unprotected implants.

DPAGT1-CDG: report of a patient with fetal hypokinesia phenotype.

Congenital disorders of glycosylation (CDG) are due to either defects in the synthesis of the glycan moiety of glycoproteins or glycolipids and in the attachment of the glycans to proteins and lipids. Some 50 CDG have been identified. They represent a challenge for clinicians because most are multisystem diseases with a heterogeneous spectrum of clinical manifestations with involvement of any organ and system. We report on a patient with a mutation in the glycosyltransferase encoded by the DPAGT1 gene, an infrequent CDG. He showed severe fetal hypokinesia phenotype with decreased fetal movements and polyhydramnios. At birth he showed decreased facial expression, without nasolabial folds, soft long ears, U-shaped vermilion of the upper lip, thick skin, hypertrichosis, camptodactyly, moderate multiple contractures, hypotonia and severe hypokinesia, no spontaneous movements, and very limited movements with stimuli; he died at 1½ months. Isoelectrofocusing of serum transferrin showed a type 1 pattern with increased asialo- and disialotransferrin. The study of the DPAGT1 gene showed he was a compound heterozygote for two novel point missense mutations [c.901C>T]+[c.1094T>G]. This phenotype expands the clinical features of the few DPATG1-CDG patients reported.

C-H bond functionalization via hydride transfer: formation of α-arylated piperidines and 1,2,3,4-tetrahydroisoquinolines via stereoselective intramolecular amination of benzylic C-H bonds.

We here report a study of the intramolecular amination of sp(3) C-H bonds via the hydride transfer cyclization of N-tosylimines (HT-amination). In this transformation, 5-aryl aldehydes are subjected to N-toluenesulfonamide in the presence of BF(3)·OEt(2) to effect imine formation and HT-cyclization, leading to 2-arylpiperidines and 3-aryl-1,2,3,4-tetrahydroisoquinolines in a one-pot procedure. We examined the reactivity of a range of aldehyde substrates as a function of their conformational flexibility. Substrates of higher conformational rigidity were more reactive, giving higher yields of the desired products. However, a single substituent on the alkyl chain linking the N-tosylimine and the benzylic sp(3) C-H bonds was sufficient for HT-cyclization to occur. In addition, an examination of various arenes revealed that the electronic character of the hydridic C-H bonds dramatically affects the efficiency of the reaction. We also found that this transformation is highly stereoselective; 2-substituted aldehydes yield cis-2,5-disubstituted piperidines, while 3-substituted aldehydes afford trans-2,4-disubstituted piperidines. The stereoselectivity is a consequence of thermodynamic control. The pseudoallylic strain between the arene and tosyl group on the piperidine ring is proposed to rationalize the greater stability of the isomer with the aryl ring in the axial position. This preferential placement of the arene is proposed to affect the observed stereoselectivity.

The BARD1 Cys557Ser variant and risk of familial breast cancer in a South-American population.

Since the discovery of the BRCA1 and BRCA2 genes, much work has been carried out to identify further breast cancer (BC) susceptibility genes. BARD1 (BRCA1-associated ring domain) was originally identified as a BRCA1-interacting protein but has also been described in tumor-suppressive functions independent of BRCA1. Some association studies have suggested that the BARD1 Cys557Ser variant might be associated with increased risk of BC, but others have failed to confirm this finding. To date, this variant has not been analyzed in Spanish or South-American populations. In this study, using a case-control design, we analyzed the C-terminal Cys557Ser change in 322 Chilean BC cases with no mutations in BRCA1 or BRCA2 and in 570 controls in order to evaluate its possible association with BC susceptibility. BARD1 Cys557Ser was associated with an increased BC risk (P = 0.04, OR = 3.4 [95 % CI 1.2-10.2]) among cases belonging to families with a strong family history of BC. No difference between single cases affected with age <50 years at diagnosis (n = 117) and controls was observed for carriers of Cys/Ser genotype. It is likely that this variant is not involved in BC risk in this group of women. We also analyzed a possible interaction between BARD1 557Ser/XRCC3 241Met variants considering the role of both genes in the maintenance of genome integrity. The combined genotype Cys/Ser-carrier with the XRCC3 241Met allele was associated with an increased BC risk (P = 0.02, OR = 5.01 [95 % CI 1.36-18.5]) among women belonging to families with at least three BC and/or ovarian cancer cases. Our results suggest that BARD1 557Ser and XRCC3 241Met may play roles in BC risk in women with a strong family history of BC. Nevertheless there is no evidence of an interaction between the two SNPs. These findings should be confirmed by other studies and in other populations.

New Insights into the Chemical Composition of Ayahuasca.

Ayahuasca is a psychedelic beverage originally from the Amazon rainforest used in different shamanic settings for medicinal, spiritual, and cultural purposes. It is prepared by boiling in water an admixture of the Amazonian vine Banisteriopsis caapi, which is a source of ß-carboline alkaloids, with plants containing N,N-dimethyltryptamine, usually Psychotria viridis. While previous studies have focused on the detection and quantification of the alkaloids present in the drink, less attention has been given to other nonalkaloid components or the composition of the solids suspended in the beverage, which may also affect its psychoactive properties. In this study, we used nuclear magnetic resonance (NMR) and liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) to study the composition of ayahuasca samples, to determine their alkaloid qualitative and quantitative profiles, as well as other major soluble and nonsoluble components. For the first time, fructose was detected as a major component of the samples, while harmine (a ß-carboline previously described as an abundant alkaloid in ayahuasca) was found to be present in the solids suspended in the beverage. In addition, N,N-dimethyltryptamine (DMT), harmine, tetrahydroharmine, harmaline, and harmol were identified as the major alkaloids present in extracts of all samples. Finally, a novel, easy, and fast method using quantitative NMR was developed and validated to simultaneously quantify the content of these alkaloids found in each ayahuasca sample.

Several generations of chemoenzymatic synthesis of oseltamivir (Tamiflu): evolution of strategy, quest for a process-quality synthesis, and evaluation of efficiency metrics.

Four generations of chemoenzymatic approaches to oseltamivir are presented. The first two generations relied on the use of cyclohexadiene-cis-diol derived enzymatically from bromobenzene. The third and fourth generation used the corresponding diol obtained from ethyl benzoate by fermentation with E. coli JM109(pDTG601a). Oseltamivir was obtained from ethyl benzoate by intersecting intermediate 39 (third-generation synthesis) and intermediate 45 (fourth-generation synthesis). Both of these advanced approaches benefited from symmetry considerations and translocation of the acrylate double bond with concomitant elimination of the C-1 hydroxyl. The syntheses are evaluated for overall efficiency by the use of efficiency metrics and compared with other syntheses of oseltamivir (both academic and industrial).

Efficient Access to the Iboga Skeleton: Optimized Procedure to Obtain Voacangine from Voacanga africana Root Bark.

Iboga alkaloids are a group of monoterpenoid indole alkaloids with promising and intriguing biological activities. Ibogaine is the representative member of the series and has become widely known as a potent atypical psychedelic with promising effects to treat substance use disorder. Nowadays, an efficient and scalable enantioselective total synthesis of ibogaine and related iboga alkaloids is still lacking, so direct extraction from natural sources or semi-synthetic schemes are the methods of choice to obtain them in a preparative scale. In particular, ibogaine can be obtained either by a low yielding direct isolation from Tabernanthe iboga or using a semi-synthetic procedure from voacangine, an iboga alkaloid occurring in a higher yield in the root bark of Voacanga africana. In this work, we describe an optimized process to obtain voacangine from V. africana root bark as a precursor of the iboga scaffold. Using a direct acetone-based extraction procedure (0.5 kg of root bark), voacangine was isolated in ∼0.8% of root bark dried weight, while the major alkaloids isolated from the bark were identified as iboga-vobasinyl dimers (∼3.7%) such as voacamine and voacamidine. Since these alkaloids contain the voacangine moiety in their structure, the cleavage of the dimers was further optimized, affording an extra amount of voacangine in ∼50% isolated molar yield. In this manner, the total amount of voacangine obtained by application of the whole procedure to the plant material (extraction and dimer cleavage) could almost duplicate the content originally found in the root bark.

EEG Gamma Band Alterations and REM-like Traits Underpin the Acute Effect of the Atypical Psychedelic Ibogaine in the Rat.

Ibogaine is a psychedelic alkaloid that has attracted large scientific interest because of its antiaddictive properties in observational studies in humans as well as in animal models. Its subjective effect has been described as intense, vivid dream-like experiences occurring while awake; hence, ibogaine is often referred to as an oneirogenic psychedelic. While this unique dream-like profile has been hypothesized to aid the antiaddictive effects, the electrophysiological signatures of this psychedelic state remain unknown. We previously showed in rats that ibogaine promotes a waking state with abnormal motor behavior along with a decrease in NREM and REM sleep. Here, we performed an in-depth analysis of the intracranial electroencephalogram during "ibogaine wakefulness". We found that ibogaine induces gamma oscillations that, despite having larger power than control levels, are less coherent and less complex. Further analysis revealed that this profile of gamma activity compares to that of natural REM sleep. Thus, our results provide novel biological evidence for the association between the psychedelic state and REM sleep, contributing to the understanding of the brain mechanisms associated with the oneirogenic psychedelic effect of ibogaine.

A Single Administration of the Atypical Psychedelic Ibogaine or Its Metabolite Noribogaine Induces an Antidepressant-Like Effect in Rats.

Anecdotal reports and open-label case studies in humans indicated that the psychedelic alkaloid ibogaine exerts profound antiaddictive effects. Ample preclinical evidence demonstrated the efficacy of ibogaine, and its main metabolite, noribogaine, in substance-use-disorder rodent models. In contrast to addiction research, depression-relevant effects of ibogaine or noribogaine in rodents have not been previously examined. We have recently reported that the acute ibogaine administration induced a long-term increase of brain-derived neurotrophic factor mRNA levels in the rat prefrontal cortex, which led us to hypothesize that ibogaine may elicit antidepressant-like effects in rats. Accordingly, we characterized behavioral effects (dose- and time-dependence) induced by the acute ibogaine and noribogaine administration in rats using the forced swim test (FST, 20 and 40 mg/kg i.p., single injection for each dose). We also examined the correlation between plasma and brain concentrations of ibogaine and noribogaine and the elicited behavioral response. We found that ibogaine and noribogaine induced a dose- and time-dependent antidepressant-like effect without significant changes of animal locomotor activity. Noribogaine's FST effect was short-lived (30 min) and correlated with high brain concentrations (estimated >8 µM of free drug), while the ibogaine's antidepressant-like effect was significant at 3 h. At this time point, both ibogaine and noribogaine were present in rat brain at concentrations that cannot produce the same behavioral outcome on their own (ibogaine ∼0.5 µM, noribogaine ∼2.5 µM). Our data suggests a polypharmacological mechanism underpinning the antidepressant-like effects of ibogaine and noribogaine.