Tobacco Alkaloids Research Articles

Assessment of the Exposure to Tobacco-Specific Nitrosamines and Minor Tobacco Alkaloids in Users of Various Tobacco/Nicotine Products.

Tobacco-specific nitrosamines (TSNAs), in particular, the human carcinogens 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N'-nitrosonornicotine (NNN), are important toxicants in tobacco and also (as contaminants) in nicotine products. In a clinical study comprising a period of 74 h under confinement, we investigated the exposure to NNK, NNN, N'-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT) as well as to the minor tobacco alkaloids anabasine (AB) and anatabine (AT) by measuring suitable biomarkers in habitual users of combustible cigarettes (CCs), electronic cigarettes (ECs), heated tobacco products (HTPs), oral tobacco (OT), and nicotine replacement therapy products (NRTs). Non-users (NU) of any tobacco/nicotine products served as the (negative) control group. Smokers exhibited the highest levels for all biomarkers measured, except for AB in urine, which was found to be highest in OT users. Somewhat elevated levels compared to NU, EC, and NRT groups were also observed in the users of HTPs. In the users of tobacco-containing products (CC, HTP, and OT), most frequently the biomarkers significantly correlated with the dose markers such as daily consumption, urinary nicotine equivalents (Nequ), and plasma cotinine (CotP). In conclusion, except for smokers (CC) and OT users, exposure of users of ECs, HTPs, and NRTs to TSNAs as well as the minor tobacco alkaloids AB and AT is marginal and statistically not distinguishable from that of NU. Finally, our results for NNN in the saliva provide preliminary evidence for the formation of NNN from the precursor nornicotine in the presence of thiocyanate as a catalyst. The latter hypothesis requires experimental verification.

Anatabine, Nornicotine, and Anabasine Reduce Weight Gain and Body Fat through Decreases in Food Intake and Increases in Physical Activity.

Obesity is a leading cause of preventable death in the United States. Currently approved pharmacotherapies for the treatment of obesity are associated with rebound weight gain, negative side effects, and the potential for abuse. There is a need for new treatments with fewer side effects. Minor tobacco alkaloids (MTAs) are potential candidates for novel obesity pharmacotherapies. These alkaloids are structurally related to nicotine, which can help reduce body weight, but without the same addictive potential. The purpose of the current study was to examine the effects of three MTAs (nornicotine, anatabine, and anabasine) and nicotine on weight gain, body composition, chow intake, and physical activity. We hypothesized that the MTAs and nicotine would reduce weight gain through reductions in chow intake and increases in physical activity. To test this, male Sprague Dawley rats were housed in metabolic phenotyping chambers. Following acclimation to these chambers and to (subcutaneous (sc)) injections of saline, animals received daily injections (sc) of nornicotine, anabasine, anatabine, or nicotine for one week. Compared to saline-injected animals that gained body weight and body fat during the treatment phase, injections of nornicotine and anatabine prevented additional weight gain, alongside reductions in body fat. Rats receiving anabasine and nicotine gained body weight at a slower rate relative to rats receiving saline injections, and body fat remained unchanged. All compounds reduced the intake of chow pellets. Nornicotine and nicotine produced consistent increases in physical activity 6 h post-injection, whereas anabasine’s and anatabine’s effects on physical activity were more transient. These results show that short-term, daily administration of nornicotine, anabasine, and anatabine has positive effects on weight loss, through reductions in body fat and food intake and increases in physical activity. Together, these findings suggest that MTAs are worthy of further investigations as anti-obesity pharmacotherapies.

Impact of acute and chronic nicotine administration on midbrain dopaminergic neuron activity and related behaviours in TRPV1 knock-out juvenile mice.

The addictive properties of nicotine, the main alkaloid in tobacco and tobacco-derived products, largely depend on its action on the activity of midbrain dopamine (DA) neurons. The transient receptor potential vanilloid 1 (TRPV1) channel has also been examined as an emerging contributor to addiction-related symptoms due to its ability to modulate midbrain neurons. Thus, the objective of our study was to explore the role of TRPV1 receptors (TRPV1Rs) on nicotine-induced behaviours and associated response of DA neuron activity. Both wild type juvenile mice and juvenile mice with invalidation of the TRPV1R gene were exposed to acute or chronic nicotine 0.3mg/kg administration. We analysed locomotor activity in response to the drug. In addition, we performed cell-attached and whole-cell recordings from ventral tegmental area (VTA) neurons after nicotine exposure. Our results showed that the genetic deletion of TRPV1Rs reduced nicotine-induced locomotor sensitization. In addition, it provided evidence in support of TRPV1Rs being regulators of inhibitory synaptic transmission in the VTA. However, TRPV1Rs did not seem to modulate either nicotine-induced conditioning place preference or nicotine-evoked electrical activity of DA neurons. In conclusion, TRPV1Rs modulate nicotine-induced psychomotor sensitization in mice independently of a control on VTA DA neuron activity. Thus, TRPV1R control may depend on another key player of the mesolimbic circuit.

Comprehensive metabolic study of nicotine in equine plasma and urine using liquid chromatography/high-resolution mass spectrometry for the identification of unique biomarkers for doping control

Nicotine is classified as a stimulant, and its use is banned in horse racing and equestrian sports by the International Federation of Horseracing Authorities and the Fédération Équestre Internationale, respectively. Because nicotine is a major alkaloid of tobacco leaves, there is a potential risk that doping control samples may be contaminated by tobacco cigarettes or smoke during sample collection. In order to differentiate the genuine doping and sample contamination with tobacco leaves, it is necessary to monitor unique metabolites as biomarkers for nicotine administration and intake. However, little is known about the metabolic fate of nicotine in horses. This is the first report of comprehensive metabolism study of nicotine in horses. Using liquid chromatography/electrospray ionization high-resolution mass spectrometry, we identified a total of 17 metabolites, including one novel horse-specific metabolite (i.e., 4-hydroxy-4-(3-pyridyl)-N-methylbutanamide), in post-administration urine samples after nasoesophageal administration of nicotine to three thoroughbred mares; eight of these compounds were confirmed based on reference standards. Among these metabolites, N-hydroxymethylnorcotinine was the major urinary metabolite in equine, but it could only be tentatively identified by mass spectral interpretation due to the lack of reference material. In addition, we developed simultaneous quantification methods for the eight target analytes in plasma and urine, and applied them to post-administration samples to establish elimination profiles of nicotine and its metabolites. The quantification results revealed that trans-3′-hydroxycotinine could be quantified for the longest period in both plasma (72 h post-administration) and urine (96 h post-administration). Therefore, this metabolite is the most appropriate monitoring target for nicotine exposure for the purpose of doping control due to its long detection times and the availability of its reference material. Further, we identified trans-3′-hydroxycotinine as a unique biomarker allowing differentiation between nicotine administration and sample contamination with tobacco leaves.

Количественное изменение никотина в табачном сырье в процессе естественной ферментации под прессом

Fermentation of tobacco raw materials is an integral part of the technological process, in which tobacco acquires its consumer qualities. During this period, there are significant qualitative and quantitative changes in its chemical composition. The purpose of this work was to study the quantitative change in the main alkaloid of tobacco – nicotine – during natural fermentation under pressure. For this purpose, a method was developed for the quantitative determination of nicotine in tobacco raw materials by high-performance liquid chromatography (HPLC) with preliminary preparation of aqueous extracts by the Soxlet method. Pipe and cigar blends were used as the analyzed samples. Fermentation of the samples was carried out at a temperature of 20°C and a relative humidity of 70%. Nicotine determination was carried out on a liquid chromatograph with a spectrophotometric detector at a wavelength of 254 nm by an external standard method. Previously, its chromatographic characteristics, such as retention time, peak height and peak area, were determined for the external standard. The studies revealed the dependence of the nicotine content in tobacco samples on the fermentation time for 6 months. Chromatography results showed that during fermentation there is a decrease in the nicotine content for all types of tobacco blends. At the same time, the most intense quantitative change occurs in the interval of 1–3 months. The decrease in nicotine during this time period was 21.0–26.9%. The obtained data can be used to manage the technological process at the formation of the flavor profile for finished tobacco products.

Accuracy Improvement of GC–MS Determination of Seven Minor Tobacco Alkaloids in Mainstream Cigarette Smoke Using Novel Analyte Protectants

Accuracy Improvement of GC–MS Determination of Seven Minor Tobacco Alkaloids in Mainstream Cigarette Smoke Using Novel Analyte Protectants

Cotinine: Pharmacologically Active Metabolite of Nicotine and Neural Mechanisms for Its Actions.

Tobacco use disorder continues to be a leading public health issue and cause of premature death in the United States. Nicotine is considered as the major tobacco alkaloid causing addiction through its actions on nicotinic acetylcholine receptors (nAChRs). Current pharmacotherapies targeting nicotine’s effects produce only modest effectiveness in promoting cessation, highlighting the critical need for a better understanding of mechanisms of nicotine addiction to inform future treatments. There is growing interest in identifying potential contributions of non-nicotine components to tobacco reinforcement. Cotinine is a minor alkaloid, but the major metabolite of nicotine that can act as a weak agonist of nAChRs. Accumulating evidence indicates that cotinine produces diverse effects and may contribute to effects of nicotine. In this review, we summarize findings implicating cotinine as a neuroactive metabolite of nicotine and discuss available evidence regarding potential mechanisms underlying its effects. Preclinical findings reveal that cotinine crosses the blood brain barrier and interacts with both nAChRs and non-nAChRs in the nervous system, and produces neuropharmacological and behavioral effects. Clinical studies suggest that cotinine is psychoactive in humans. However, reviewing evidence regarding mechanisms underlying effects of cotinine provides a mixed picture with a lack of consensus. Therefore, more research is warranted in order to provide better insight into the actions of cotinine and its contribution to tobacco addiction.

In-vitro immunomodulatory effects of nicotine on Nitric Oxide, interleukin 1β and interleukin 37 production in human peripheral blood mononuclear cells (PBMC) from patients with Behçet disease

Behçet's disease is a chronic systemic inflammatory disorder associated with a cytokine profile disruption and increased nitric oxide levels. In our current study we sought to evaluate the in-vitro modulatory effect of nicotine, the principal alkaloid of tobacco, on nitric oxide (NO), interleukin 1β (IL-1β) and interleukin 37 (IL-37) production during Behçet's disease. Peripheral blood mononuclear cells cultures were performed with or without nicotine (200 μg/ml). Culture supernatants were harvested after 24 h of incubation. NO, IL-1β and IL-37 measurements were, respectively, performed by modified Griess method and ELISA sandwich. Our results showed that nicotine significantly reduced NO and IL-1β levels in patients with Behçet’s disease, while it increased IL-37 production. Our results showed no sex differences in the effects of nicotine on the production of nitric oxide and IL-1β nor IL-37 in PBMC of patients. Our findings suggest that nicotine may provide a potential therapeutic strategy targeting inflammation during Behçet’s disease.

Firstly Electrochemical Examination of Myosmine at Glassy Carbon Electrode: Sensitive Determination in Tobacco Leaves by Differential Pulse Voltammetry

AbstractIn this study, the electrochemical properties of myosmine, one of the tobacco alkaloids, were investigated for the first time using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques on glassy carbon electrode (GCE). Using GCE with CV technique, it gave an irreversible reduction peak with diffusion control at about −1.38 V in Britton‐Robinson (BR, pH 12.0) medium. A good linear relationship between concentration and current in the range of 0.5 μM–3.5 μM in BR (pH 12.0) medium on GCE with DPV technique [Ip(μA)=0.847 C(μM)+0.114, r=0.995, n=7] has been observed. The proposed method has been successfully applied to tobacco leaves.

A de novo regulation design shows an effectiveness in altering plant secondary metabolism

IntroductionTranscription factors (TFs) and cis-regulatory elements (CREs) control gene transcripts involved in various biological processes. We hypothesize that TFs and CREs can be effective molecular tools for De Novo regulation designs to engineer plants. ObjectivesWe selected two Arabidopsis TF types and two tobacco CRE types to design a De Novo regulation and evaluated its effectiveness in plant engineering. MethodsG-box and MYB recognition elements (MREs) were identified in four Nicotiana tabacum JAZs (NtJAZs) promoters. MRE-like and G-box like elements were identified in one nicotine pathway gene promoter. TF screening led to select Arabidopsis Production of Anthocyanin Pigment 1 (PAP1/MYB) and Transparent Testa 8 (TT8/bHLH). Two NtJAZ and two nicotine pathway gene promoters were cloned from commercial Narrow Leaf Madole (NL) and KY171 (KY) tobacco cultivars. Electrophoretic mobility shift assay (EMSA), cross-linked chromatin immunoprecipitation (ChIP), and dual-luciferase assays were performed to test the promoter binding and activation by PAP1 (P), TT8 (T), PAP1/TT8 together, and the PAP1/TT8/Transparent Testa Glabra 1 (TTG1) complex. A DNA cassette was designed and then synthesized for stacking and expressing PAP1 and TT8 together. Three years of field trials were performed by following industrial and GMO protocols. Gene expression and metabolic profiling were completed to characterize plant secondary metabolism. ResultsPAP1, TT8, PAP1/TT8, and the PAP1/TT8/TTG1 complex bound to and activated NtJAZ promoters but did not bind to nicotine pathway gene promoters. The engineered red P + T plants significantly upregulated four NtJAZs but downregulated the tobacco alkaloid biosynthesis. Field trials showed significant reduction of five tobacco alkaloids and four carcinogenic tobacco specific nitrosamines in most or all cured leaves of engineered P + T and PAP1 genotypes. ConclusionG-boxes, MREs, and two TF types are appropriate molecular tools for a De Novo regulation design to create a novel distant-pathway cross regulation for altering plant secondary metabolism.

Characterisation of vaping liquids used in vaping devices across four countries: results from an analysis of selected vaping liquids reported by users in the 2016 ITC Four Country Smoking and Vaping Survey

ObjectivesThis study presents an analysis of vaping products (VPs) purchased in the USA, Canada, England and Australia and assesses whether differences in regulations were associated with differences in the chemical...

Nicotine and its metabolite cotinine target MD2 and inhibit TLR4 signaling

Nicotine is the principal alkaloid of tobacco often manufactured into cigarettes and belongs to a highly addictive class of drugs. Nicotine attenuates the neuroinflammation induced by microglial activation. However, the molecular target(s) underlying anti-inflammatory action of nicotine has not been fully understood. Considering the psychoactive substances morphine, cocaine, and methamphetamine act as xenobiotic-associated molecular patterns and can be specifically sensed by the innate immune receptor Toll-like receptor 4 (TLR4), here we sought to delineate whether nicotine and/or its metabolite cotinine may be recognized by the innate immune system via myeloid differentiation protein 2 (MD2), an accessory protein of TLR4 that is responsible for ligand recognition. MD2-intrinsic fluorescence titrations, surface plasmon resonance, and competitive displacement binding assays with curcumin (MD2 probe) demonstrated that both nicotine and cotinine targeted the lipopolysaccharide (LPS; TLR4 agonist) binding pocket of MD2 with similar affinities. The cellular thermal shift assay indicated that nicotine binding increased, while cotinine binding decreased, MD2 stability. These biophysical binding results were further supported by in silico simulations. In keeping with targeting MD2, both nicotine and cotinine inhibited LPS-induced production of nitric oxide and tumor necrosis factor alpha (TNF-α) and blocked microglial activation. Neither a pan nicotinic acetylcholine receptor (nAChR) inhibitor nor RNAi for nAChRs abolished the suppressive effect of nicotine- and cotinine-induced neuroinflammation. These data indicate that TLR4 inhibition by nicotine and cotinine at the concentrations tested in BV-2 cells is independent of classic neuronal nAChRs and validate that MD2 is a direct target of nicotine and cotinine in the inhibition of innate immunity.

Development of an Advanced Multicellular Intestinal Model for Assessing Immunomodulatory Properties of Anti-Inflammatory Compounds.

Intestinal inflammation is the collective term for immune system-mediated diseases of unknown, multifactorial etiology, with often complex interactions between genetic and environmental factors. To mechanistically investigate the effect of treatment with compounds possessing immunomodulating properties in the context of intestinal inflammation, we developed an immunocompetent in vitro triculture intestinal model consisting of a differentiated intestinal epithelial layer (Caco-2/HT29-MTX) and immunocompetent cells (differentiated THP-1). The triculture mimicked a healthy intestine with stable barrier integrity. Lipopolysaccharide treatment triggered a controlled and reversible inflammatory state, resulting in significant impairment of barrier integrity and release of pro-inflammatory cytokines and chemokines, which are known hallmarks of intestinal inflammation. Treatment with known anti-inflammatory reference compounds (TPCA-1 and budenoside) prevented the induction of an inflammatory state; the decreasing triculture responses to this treatment measured by cytokine release, transepithelial electric resistance (TEER), and epithelial layer permeability proved the suitability of the intestinal model for anti-inflammatory drug screening. Finally, selected tobacco alkaloids (nicotine and anatabine (R/S and S forms)) were tested in the in vitro triculture for their potential anti-inflammatory properties. Indeed, naturally occurring alkaloids, such as tobacco-derived alkaloids, have shown substantial anti-inflammatory effects in several in vitro and in vivo models of inflammation, gaining increasing interest. Similar to the anti-inflammatory reference compounds, one of the tobacco alkaloids under investigation partially prevented the decrease in the TEER and increase in permeability and reduced the release of pro-inflammatory cytokines and chemokines. Taken together, these data confirm that our in vitro model is suitable for screening potential anti-inflammatory compounds in the context of intestinal inflammation.

Ubiquitous atmospheric contamination by tobacco smoke: Nicotine and a new marker for tobacco smoke-derived particulate matter, nicotelline

Second Hand Smoke (SHS) has always been primarily linked with indoor pollution. To date nicotine was the favoured marker for SHS alongside measurements of particulate matter (PM) levels. As nicotine is mainly found in the gas-phase and reactive in the outdoor environment it is not ideal as a marker for the SHS-driven particulate component in PM. Nicotelline, a minor tobacco alkaloid that is stable, found almost exclusively in the particle phase and easy to quantify even at low concentrations, is being proposed as a better marker. It is the first study using bisulfate-treated quartz fiber filters to show that airborne nicotine (gas+particle phase) is directly proportional to airborne nicotelline in countries that have different climates. The analytical method developed has been validated to show that the use of untreated filters is suitable for the quantification of nicotelline even at low concentrations. Although nicotelline exhibits a seasonal and geographical variation, this is the first comprehensive study which demonstrates the ubiquitous presence of nicotelline in PM from outdoor air samples collected in the USA (0.1–285.6 pgm−3), UK (2.3–9.1 pgm−3), Hong Kong (3.8–109.3 pgm−3) and Malta (4.2–280.8 pgm−3). From the nicotelline apportionment factor of 1589 ng/mg of tobacco smoke PM we estimate the fraction of outdoor airborne PM derived from SHS to be in the range of 0.03–0.08%. While it is unlikely for tobacco smoke-related toxics in outdoor PM to be considered a major health hazard, in heavily polluted microenvironments this marker would be useful in tracing the presence of SHS and emerging Third Hand Smoke components that form or are found in airborne and settled PM that could induce serious health effects.

Recent Developments in the Determination of Biomarkers of Tobacco Smoke Exposure in Biological Specimens: A Review.

Environmental tobacco smoke exposure (ETS) and smoking have been described as the most prevalent factors in the development of certain diseases worldwide. According to the World Health Organization, more than 8 million people die every year due to exposure to tobacco, around 7 million due to direct ETS and the remaining due to exposure to second-hand smoke. Both active and second-hand exposure can be measured and controlled using specific biomarkers of tobacco and its derivatives, allowing the development of more efficient public health policies. Exposure to these compounds can be measured using different methods (involving for instance liquid- or gas-chromatographic procedures) in a wide range of biological specimens to estimate the type and degree of tobacco exposure. In recent years, a lot of research has been carried out using different extraction methods and different analytical equipment; this way, liquid–liquid extraction, solid-phase extraction or even miniaturized procedures have been used, followed by chromatographic analysis coupled mainly to mass spectrometric detection. Through this type of methodologies, second-hand smokers can be distinguished from active smokers, and this is also valid for e-cigarettes and vapers, among others, using their specific biomarkers. This review will focus on recent developments in the determination of tobacco smoke biomarkers, including nicotine and other tobacco alkaloids, specific nitrosamines, polycyclic aromatic hydrocarbons, etc. The methods for their detection will be discussed in detail, as well as the potential use of threshold values to distinguish between types of exposure.

Leachates from Cigarette Butts Can Persist in Marine Sediment

Cigarette butts (CBs) can travel via stormwater runoff so they are very common on the beach. While there is evidence they can leach toxic chemicals into water, there is not much information about their behavior in sediment. We buried CBs in aquaria containing marine sediment at a concentration of 0.025 CB/g, and sampled it after 0, 5, 10, 20, 45, and 60 days. The sediment was solvent-extracted and analyzed by GC/MS. The chromatograms were compared to those of CB extracts to look for compounds in common. Nicotine, β-nicotyrine, myosmine, cotinine, linear alkanes, and xylenol were detected in the sediment up to 60 days from exposure so the leachates could have long-term impact on benthic fauna. The tobacco alkaloids or its metabolites could be used as specific markers of cigarette litter in sediment monitoring. These outcomes support the need for stricter regulation on cigarette waste to prevent it from reaching aquatic environments.

Electrophoretic Purification and Characterization of Human NADH-Glutamate Dehydrogenase Redox Cycle Isoenzymes Synthesizing Nongenetic Code-Based RNA Enzyme

NADH-glutamate dehydrogenase (GDH) is active in human tissues, and is chromatographically purified, and studied because it participates in synthesizing glutamate, a neurotransmitter. But chromatography dissociates the GDH isoenzymes that synthesize nongenetic code-based RNA enzymes degrading superfluous mRNAs thereby aligning the cellular reactions with the environment of the organism. The aim was to electrophoretically purify human hexameric GDH isoenzymes and to characterize their RNA enzyme synthetic activity as in plants. The outcome could be innovative in chemical dependency diagnosis and management. Multi metrix electrophoresis including free solution isoelectric focusing, and through polyacrylamide and agarose gels were deployed to purify the redox cycle isoenzymes of laryngeal GDH, and to assay their RNA enzyme synthetic activities. The laryngeal GDH displayed the 28 binomial isoenzymes typical of higher organisms. Isoelectric focusing purification produced pure GDH. Redox cycle assays of the GDH isoenzymes produced RNA enzymes that degraded human stomach total RNA. In the reaction mechanism, the Schiff-base intermediate complex between α-ketoglutarate and GDH is the target of nucleophiles, resulting to the disruption of synthesis of glutamate, and RNA enzyme. The strongest nucleophiles are the psychoactive alkaloids of tobacco, cocaine, opium poppy, cannabis smoke because they are capable of reacting with GDH Schiff base intermediate to stimulate synthesis of aberrant RNA enzymes that degrade cohorts of mRNAs thereby changing the biochemical pathways and exacerbating drug overdose and chemical dependency. Electrophoretic purification, and characterization of the RNA enzyme synthetic activity set the forecourt for innovative application of GDH redox cycles in the diagnostic management of chemical dependency.

Structural Insights into 6-Hydroxypseudooxynicotine Amine Oxidase from Pseudomonas geniculata N1, the Key Enzyme Involved in Nicotine Degradation.

Bacteria degrade nicotine mainly using pyridine and pyrrolidine pathways. Previously, we discovered a hybrid of the pyridine and pyrrolidine pathways (the VPP pathway) in Pseudomonas geniculata N1 and characterized its key enzyme, 6-hydroxypseudooxynicotine amine oxidase (HisD). It catalyzes oxidative deamination of 6-hydroxypseudooxynicotine to 6-hydroxy-3-succinoylsemialdehyde-pyridine, which is the crucial step connecting upstream and downstream portions of the VPP pathway. We determined the crystal structure of wild-type HisD to 2.6 Å. HisD is a monomer that contains a flavin mononucleotide, an iron-sulfur cluster, and ADP. On the basis of sequence alignment and structure comparison, a difference has been found among HisD, closely related trimethylamine dehydrogenase (TMADH), and histamine dehydrogenase (HADH). The flavin mononucleotide (FMN) cofactor is not covalently bound to any residue, and the FMN isoalloxazine ring is planar in HisD compared to TMADH or HADH, which forms a 6-S-cysteinyl flavin mononucleotide cofactor and has an FMN isoalloxazine ring in a "butterfly bend" conformation. Based on the structure, docking study, and site-directed mutagenesis, the residues Glu60, Tyr170, Asp262, and Trp263 may be involved in substrate binding. The expanded understanding of the substrate binding mode from this study may guide rational engineering of such enzymes for biodegradation of potential pollutants or for bioconversion to generate desired products.IMPORTANCE Nicotine is a major tobacco alkaloid in tobacco waste. Pyridine and pyrrolidine pathways are the two best-elucidated nicotine metabolic pathways; Pseudomonas geniculata N1 catabolizes nicotine via a hybrid between the pyridine and pyrrolidine pathways. The crucial enzyme, 6-hydroxypseudooxynicotine amine oxidase (HisD), links the upstream and downstream portions of the VPP pathway; however, there is little structural information about this important enzyme. In this study, we determined the crystal structure of HisD from Pseudomonas geniculata N1. Its basic insights about the structure may help us to guide the engineering of such enzymes for bioremediation and bioconversion applications.

Anatabine ameliorates intestinal inflammation and reduces the production of pro-inflammatory factors in a dextran sulfate sodium mouse model of colitis

BackgroundInflammatory bowel disease (IBD) is the collective term for chronic immune-mediated diseases of unknown, multifactorial etiology, arising from the interplay between genetic and environmental factors and including two main disease manifestations: ulcerative colitis (UC) and Crohn’s disease. In the last few decades, naturally occurring alkaloids have gained interest because of their substantial anti-inflammatory effects in several animal models of disease. Studies on mouse models of IBD have demonstrated the anti-inflammatory action of the main tobacco alkaloid, nicotine. In addition, anatabine, a minor tobacco alkaloid also present in peppers, tomato, and eggplant presents anti-inflammatory properties in vivo and in vitro. In this study, we aimed to evaluate the anti-inflammatory properties of nicotine and anatabine in a dextran sulfate sodium (DSS) mouse model of UC.ResultsOral administration of anatabine, but not nicotine, reduced the clinical symptoms of DSS-induced colitis. The result of gene expression analysis suggested that anatabine had a restorative effect on global DSS-induced gene expression profiles, while nicotine only had limited effects. Accordingly, MAP findings revealed that anatabine reduced the colonic abundance of DSS-associated cytokines and increased IL-10 abundance.ConclusionsOur results support the amelioration of inflammatory effects by anatabine in the DSS mouse model of UC, and suggest that anatabine constitutes a promising therapeutic agent for IBD treatment.

Evaluating the Concentration of Cotinine, Lead and Cadmium in Newborns with Respsiratory Distress Syndrome

Background Respiratory distress syndrome is one of the most common problems of newborns. Respiratory distress syndrome occurs when there is no enough surfactant in the lungs. Heavy metals are naturally occurring elements that have a high atomic weight and a density at least 5 times greater than that of water. Lead is a heavy metal, it is important environmental toxicant; the toxic effects of lead include many systems in the body like central and peripheral nervous system. Cadmium is heavy metal that exerts toxic effects on the kidney, the skeletal and the respiratory systems, and is classified as a human carcinogen. Nicotine, the main alkaloid of tobacco. It is readily absorbed from tobacco smoke, and its concentration rises over 6-8 hours during the day in regular smokers. About 70 to 80% of nicotine is metabolized to cotinine. Methods The study was carried out for 50 newborns divided in two groups: Group 1: 25 newborns with respiratory distress syndrome. Group 2: 25 newborns without respiratory distress syndrome. Results According to Demographic characteristics there are no significant differences when compered the age, gender, duration of pregnancy and the age of the mothers of newborns with respiratory distress syndrome and normal newborns (p<0.05). the whole blood lead and serum cotinine concentration in newborns with respiratory distress syndrome was significantly higher compering with normal newborns (p<0.05). The whole blood cadmium concentration in newborns with respiratory distress syndrome was not significantly different comparing with normal newborns (p<0.05). Conclusions Newborns with respiratory distress syndrome have high serum level of cotinine and whole blood lead when compared to healthy newborns.