Tobacco Compounds Research Articles

PHOSPHORYLATION OF CALCIUM/CALMODULIN-DEPENDENT PROTEIN KINASE II (CAMKII) AND EXTRACELLULAR REGULATED KINASE (ERK) IN STRIATUM MEDIATE NICOTINE DEPENDENCE IN BALB/C MICE

Objective: Nicotine is an active compound in tobacco and has a rewarding effect in the central nervous system (CNS), which may lead to dependence. Although nicotine dependence is elucidated by brain mechanisms, synaptic molecular substrates underlying the dependence remain unclear. We hypothesized that reward signaling is mediated by dopamine and glutamate receptors, in where calcium/calmodulin-dependent kinase II (CaMKII) and extracellular signal-regulated kinase (ERK) may mediate the synaptic signaling of dependence.
 Methods: To investigate the roles of both CaMKII and ERK on nicotine dependence were assessed by conditioned place preference (CPP) methods followed by dissection. One day after conditioning, preference scores were measured to evaluate nicotine dependence. Mice were sacrificed and their striatum were dissected out for immunoblotting analyses of CaMKII and ERK phosphorylation.
 Results: Nicotine-induced conditioned place preference as a symptom of nicotine dependence. CaMKII and ERK phosphorylation in striatum significantly increased along with the development of nicotine dependence.
 Conclusion: We should next apply pharmacological strategies to manipulate CaMKII and ERK signaling. In particular, disruption of reconsolidation by disrupting CaMKII and ERK signaling may propose an attractive therapeutic approach to inhibit nicotine dependence.

Determination of Volatiles in Flue-Cured Tobacco by Gas Chromatography–Mass Spectrometry (GC–MS) with Chemometrics

This study reports the utilization of two-step headspace (HS) to profile the volatile compounds of flue-cured tobacco. The relationship between the volatile components and geographic origin was investigated using multivariate data analysis. To avoid the impact of adsorption caused by tobacco on the HS extraction, the tobacco was soaked by saturated NaCl solutions prior to the HS sampling. However, the introduction of water vapor may affect the subsequent gas chromatography–mass spectrometry (GC–MS) analysis. Thus, two-step HS, which is based on the coupling of the programmed temperature vaporizer inlet and HS autosampler, was employed to remove the water vapor while simultaneously preconcentrating the volatile compounds. The repeatability and stability were evaluated, and 80 compounds were identified from 25 flue-cured tobacco samples. Both principal component analysis (PCA) and hierarchical clustering analysis (HCA) revealed that the volatile components of flue-cured tobacco were closely related to the geographic origin. Furthermore, the characteristic volatiles of the flue-cured tobacco from different regions were illustrated using partial least squares discriminant analysis (PLS-DA). The presented work provided a simple and reliable way to profile the volatile components and characterize geographic origin of tobacco and tobacco products.

Quantitative trait locus mapping and genomic selection of tobacco (Nicotiana tabacum L.) based on high-density genetic map

Tobacco (Nicotiana tabacum L.) is an economic crop and a model organism for studies of plant biology and genetics. As an allotetraploid plant generated from interspecific hybridization, tobacco has a massive genome (4.5 Gb). Recently, a genetic map with 45,081 single nucleotide polymorphism (SNP) markers was constructed using whole-genome sequencing data for a tobacco population including 274 individuals. This provides a basis for quantitative trait locus (QTL) mapping and genomic selection, which have been widely applied to other crops but have not been feasible in tobacco. Based on this high-density genetic map, we identified QTLs associated with important agronomic traits, chemical compounds in dry leaves, and hazardous substances in processed cigarettes. The LOD values for major QTLs were highest for agronomic traits, followed by chemical compounds and hazardous substances. In addition to the identification of molecular markers, we evaluated genomic selection models and found that BayesB had the highest prediction accuracy for the recombinant inbred line population. Our results offer new insights into the genetic mechanism underlying important traits, such as agronomic traits and quality-related chemical compounds in tobacco, and will be able to support the application of molecular breeding to tobacco.

Exploring Neurobehaviour in Zebrafish Embryos as a Screening Model for Addictiveness of Substances.

Tobacco use is the leading cause of preventable death worldwide and is highly addictive. Nicotine is the main addictive compound in tobacco, but less is known about other components and additives that may contribute to tobacco addiction. The zebrafish embryo (ZFE) has been shown to be a good model to study the toxic effects of chemicals on the neurological system and thus may be a promising model to study behavioral markers of nicotine effects, which may be predictive for addictiveness. We aimed to develop a testing protocol to study nicotine tolerance in ZFE using a locomotion test with light-dark transitions as behavioral trigger. Behavioral experiments were conducted using three exposure paradigms: (1) Acute exposure to determine nicotine’s effect and potency. (2) Pre-treatment with nicotine dose range followed by a single dose of nicotine, to determine which pre-treatment dose is sufficient to affect the potency of acute nicotine. (3) Pre-treatment with a single dose combined with acute exposure to a dose range to confirm the hypothesized decreased potency of the acute nicotine exposure. These exposure paradigms showed that (1) acute nicotine exposure decreased ZFE activity in response to dark conditions in a dose-dependent fashion; (2) pre-treatment with increasing concentrations dose-dependently reversed the effect of acute nicotine exposure; and (3) a fixed pre-treatment dose of nicotine induced a decreased potency of the acute nicotine exposure. This effect supported the induction of tolerance to nicotine by the pre-treatment, likely through neuroadaptation. The interpretation of these effects, particularly in view of prediction of dependence and addictiveness, and suitability of the ZFE model to test for such effects of other compounds than nicotine, are discussed.

Self-administration by female rats of low doses of nicotine alone vs. nicotine in tobacco smoke extract

BackgroundNicotine has reinforcing effects, but there are thousands of other compounds in tobacco, some of which might interact with nicotine reinforcement. AimsThis rat study was conducted to determine if nicotine self-administration is altered by co-administration of the complex mixture of compounds in tobacco smoke extract (TSE). MethodsFemale Sprague-Dawley rats were tested for self-administration of low doses of nicotine (3 or 10 µg/kg/infusion) at three different rates of reinforcement (FR1, FR3 and FR5) over three weeks either alone or together with the complex mixture of tobacco smoke extract (TSE). ResultsRats self-administering 3 µg/kg/infusion of nicotine alone showed a rapid initiation on an FR1 schedule, but declined with FR5. Rats self-administering nicotine in TSE acquired self-administration more slowly, but increased responding over the course of the study. With 10 µg/kg/infusion rats self-administered significantly more nicotine alone than rats self-administering the same nicotine dose in TSE. Rats self-administering nicotine alone took significantly more infusions with the 10 than the 3 µg/kg/infusion dose, whereas rats self-administering nicotine in TSE did not. Nicotine in TSE led to a significantly greater locomotor hyperactivity at a dose of 0.1 mg/kg compared to rats that received nicotine alone. Rats self-administering nicotine alone had significantly more responding on the active vs. inactive lever, but rats self-administering the same nicotine doses in TSE did not. ConclusionsSelf-administration of nicotine in a purer form appears to be more clearly discriminated and dose-related than nicotine self-administered in the complex mixture of TSE.

Smoking as a factor influencing the rehabilitation process after cardiac surgery

Introduction: Comprehensive cardiac rehabilitation is a standard therapeutic procedure in patients after cardiac surgery. Its course depends on many factors. One of them is smoking. Exposure of the body to tobacco compounds reduces the supply of oxygen to the organs, which in turn has a damaging effect on the heart tissue.Objective: The aim of this study is to determine the effect of smoking on the effectiveness of rehabilitation in patients after cardiac surgery.Materials and methods: The research was carried out at the Department of Cardiac Surgery, SPSK 2, Pomeranian Medical University in Szczecin. The research was conducted among 35 patients, divided into 3 groups. The first group of 9 people (26%) were non-smokers. The second group was assigned to 11 people (31%) who were heavy smokers. The third group consisted of 15 people (43%) who had been addicted to cigarettes in the past. The research tool used in the study was the 6-minute walk test.Results: Non-smokers achieved a greater improvement in the 6-minute test score compared to the group of smokers and ex-smokers, whose mean score was lower by 39.17 m (± 100.80) and 85.74 m (± 80.56), respectively.Conclusion: Smoking may have an impact on the exercise capacity and exercise tolerance in patients after cardiac surgery.

Change in the chemical content of untreated wastewater of Athens, Greece under COVID-19 pandemic

COVID-19 pandemic spread rapidly worldwide with unanticipated effects on mental health, lifestyle, stability of economies and societies. Although many research groups have already reported SARS-CoV-2 surveillance in untreated wastewater, only few studies evaluated the implications of the pandemic on the use of chemicals by influent wastewater analysis. Wide-scope target and suspect screening were used to monitor the effects of the pandemic on the Greek population through wastewater-based epidemiology. Composite 24 h influent wastewater samples were collected from the wastewater treatment plant of Athens during the first lockdown and analyzed by liquid chromatography mass spectrometry. A wide range of compounds was investigated (11,286), including antipsychotic drugs, illicit drugs, tobacco compounds, food additives, pesticides, biocides, surfactants and industrial chemicals. Mass loads of chemical markers were estimated and compared with the data obtained under non-COVID-19 conditions (campaign 2019). The findings revealed increases in surfactants (+196%), biocides (+152%), cationic quaternary ammonium surfactants (used as surfactants and biocides) (+331%), whereas the most important decreases were estimated for tobacco (−33%) and industrial chemicals (−52%). The introduction of social-restriction measures by the government affected all aspects of life.

Curbing the Deregulation of Glycosylation in Tongue Carcinoma Cells with Natural Compounds.

Aberrant glycosylation has been recently considered as a major hallmark of cancer. Furthermore, we have reported that aberrant glycosylation, mainly sialylation and fucosylation, plays a major role in oral cancer progression and metastasis. In the present study, we evaluated the role of tobacco compounds (4-NQO, NNK, Benzopyrene), natural compounds (Curcumin, Butein and Piceatannol) and commonly used chemotherapeutic compound (Cisplatin) on sialylation and fucosylation transcript levels in the tongue cancer cell line (SAS). The SAS cells were treated with the tobacco compounds, natural compounds and Cisplatin after obtaining their IC50 values using MTT assay. After 24 hr treatment of the compounds, RNA was isolated from the cells and converted to cDNA. RT-qPCR was performed for mRNA expression of glycosylation transcripts. The treatment of tobacco compounds on the SAS cells resulted in increased mRNA levels of ST3GAL1, NEU3, FUT5 and FUT6 in a dose-dependent manner. The treatment of Curcumin and Butein resulted in lower mRNA levels of FUT8, whereas dose-dependent higher mRNA levels of FUT3 were also observed after the treatment of Curcumin. SAS cells exhibited a dose-dependent decrease in ST3GAL2, FUT5 and FUT8 mRNA after Piceatannol treatment. Furthermore, Cisplatin treatment on the SAS cells resulted in increased mRNA levels of FUT3 as the concentration increased from 100 μM to 200 μM. While, treatment of Cisplatin resulted in decreased mRNA levels of ST3GAL2, ST3GAL3, FUT5 and FUT8 in a dose-dependent manner. All together, the data revealed Piceatannol as a potent synergistic for Cisplatin to target the altered glycosylation for better treatment management of tongue carcinoma. The study provides a normal approach of targeting aberrant glycosylation with natural compounds, which may open the possibility of newer therapeutic strategies using natural compounds alone or in combination with other conventional therapies.

Nicotine prevents in vivo Aβ toxicity in Caenorhabditis elegans via SKN-1

ObjectiveNicotine, a main active compound in tobacco, has been shown to attenuate amyloid-β (Aβ) mediated neurotoxicity. However, the detailed underlying mechanisms remains to be elucidated. In this study, nematode Caenorhabditis elegans (C. elegans) had been chosen as the model animal for dissecting the role of nicotine in the prevention of Aβ-induced toxicity in vivo. MethodsCL2120 and CL4176 transgenic worms of Alzheimer’s disease (AD) models were treated with different concentrations of nicotine, and worm paralysis was monitored. Next, the effects of nicotine on Aβ deposits, Aβ oligomers, reactive oxygen species (ROS) and the oxidative stress resistance in worms were measured. Moreover, the pathway responsible for nicotine alleviating Aβ-induced toxicity in vivo was explored by observing the oxidative stress resistance of skn-1 or daf-16 mutants in the presence of nicotine. Furthermore, the worm paralysis and Aβ deposits were further checked in CL4176 worms with skn-1 RNA interference under the condition of nicotine. ResultsNicotine (5 μM) attenuated AD-like symptoms of worm paralysis in CL2120 and CL4176 transgenic C. elegans. Nicotine did not inhibit Aβ aggregation in vitro, however it suppressed Aβ deposits and reduced the Aβ oligomers to alleviate the toxicity induced by Aβ overexpression in C. elegans. Although nicotine did not possess apparent intrinsic anti-oxidative activity, it decreased in vivo reactive oxygen species (ROS). Nicotine enhanced the oxidative stress resistance of C. elegans, which was mediated by SKN-1 but not DAF-16 signaling. Furthermore, skn-1 RNAi abrogated the effect of nicotine reducing Aβ deposits in vivo and completely blocked nicotine preventing Aβ induced worm paralysis. ConclusionsNicotine reduces Aβ oligomer formation and alleviates Aβ-induced paralysis of C. elegans, which is mediated by SKN-1 signaling.

Role of sex hormones in lung cancer.

Lung cancer represents the world's leading cause of cancer deaths. Sex differences in the incidence and mortality rates for various types of lung cancers have been identified, but the biological and endocrine mechanisms implicated in these disparities have not yet been determined. While some cancers such as lung adenocarcinoma are more commonly found among women than men, others like squamous cell carcinoma display the opposite pattern or show no sex differences. Associations of tobacco product use rates, susceptibility to carcinogens, occupational exposures, and indoor and outdoor air pollution have also been linked to differential rates of lung cancer occurrence and mortality between sexes. While roles for sex hormones in other types of cancers affecting women or men have been identified and described, little is known about the influence of sex hormones in lung cancer. One potential mechanism identified to date is the synergism between estrogen and some tobacco compounds, and oncogene mutations, in inducing the expression of metabolic enzymes, leading to enhanced formation of reactive oxygen species and DNA adducts, and subsequent lung carcinogenesis. In this review, we present the literature available regarding sex differences in cancer rates, associations of male and female sex hormones with lung cancer, the influence of exogenous hormone therapy in women, and potential mechanisms mediated by male and female sex hormone receptors in lung carcinogenesis. The influence of biological sex on lung disease has recently been established, thus new research incorporating this variable will shed light on the mechanisms behind the observed disparities in lung cancer rates, and potentially lead to the development of new therapeutics to treat this devastating disease.

Evaluation of the relationship between antenatal and postnatal tobacco smoke exposure and childhood cancers.

e22011 Background: The incidence of childhood cancers increased by 1 % per year over the last three decades. Life style changes and increased variety of environmental exposures are accused of this trend. One of these environmental factors is cigarette smoking and parental smoking is the main source of tobacco smoke exposure of children. There are strong reasons for considering parental smoking behaviour as a risk factor for childhood cancers. Many tobacco related compounds are detected in fetal tissues, breast milk and tissues of children of smoking parents. However, it is hard to make causal relationship between parental smoking and childhood cancers. One of the reasons is the difficulty to detect tobacco smoke exposure. Questionnaires, commonly used method to detect tobacco smoke exposure, are prone to biases. Cotinine is the main metabolite of nicotine which is the abundant organic compound in tobacco and a good biomarker to detect tobacco smoke exposure. Methods: 104 newly diagnosed, 0-18 years aged pediatric cancer patients from two pediatric oncology centers ( Ankara University Children’s Hospital and Ankara City Hospital) and 99 healthy children aged 0-18 applied to the Ankara University Children’s Hospital participated our study. Parental smoking behaviours (preconceptional, during pregnancy and current smoking) and environmental tobacco smoke exposures (ETS) of children were compared between two groups. ETS exposures of cancer patients and healthy children were evaluated by hair cotinine ELISA analysis and questionnaire. For hair cotinine analysis, 30 mg of hair samples were taken from occipital part of scalp by a stainless scissors. Samples were processed according to manufacturer's instructions. Parents of two groups were surveyed about their smoking behaviours and ETS exposures of their children. Results: We found no differences between two groups by means of maternal preconceptional smoking, smoking during pregnancy and current smoking behaviours. Paternal preconceptional smoking and smoking during pregnancy rates were significantly low in cancer patients (p < 0,05) according to questionnaire. Environmental tobacco smoke exposures were found statistically low in cancer patients according to questionnaire (p < 0,05). However, quantitative exposure assessment by hair cotinine analysis revealed that cancer patients are exposed to tobacco smoke more than healthy children (p < 0,001). Conclusions: Our findings support that smoking could be a risk factor for childhood cancers. This study also revealed that questionnaires could cause biases. We thought, social desirability bias of father of cancer patients could be a reason of their low smoking rates according to questionnaire. We suggest that cotinine analysis along with validated questionnaires can be used to prevent biases in studies of tobacco smoke in the etiology of childhood cancers.

Nicotine suppresses Parkinson\u2019s disease like phenotypes induced by Synphilin-1 overexpression in Drosophila melanogaster by increasing tyrosine hydroxylase and dopamine levels

It has been observed that there is a lower Parkinson’s disease (PD) incidence in tobacco users. Nicotine is a cholinergic agonist and is the principal psychoactive compound in tobacco linked to cigarette addiction. Different studies have shown that nicotine has beneficial effects on sporadic and genetic models of PD. In this work we evaluate nicotine’s protective effect in a Drosophila melanogaster model for PD where Synphilin-1 (Sph-1) is expressed in dopaminergic neurons. Nicotine has a moderate effect on dopaminergic neuron survival that becomes more evident as flies age. Nicotine is beneficial on fly survival and motility increasing tyrosine hydroxylase and dopamine levels, suggesting that cholinergic agonists may promote survival and metabolic function of the dopaminergic neurons that express Sph-1. The Sph-1 expressing fly is a good model for the study of early-onset phenotypes such as olfaction loss one of the main non-motor symptom related to PD. Our data suggest that nicotine is an interesting therapeutic molecule whose properties should be explored in future research on the phenotypic modulators of the disease and for the development of new treatments.

The applicability of different tobacco types to heated tobacco products

Heated tobacco (Nicotiana tabacum L.) products develop rapidly because of its low toxicity. In order to evaluate the industrial applicability of the existing types of characteristic tobacco as raw materials for heated tobaccos, this research ascertained differences in the main chemical compositions in tobacco leaves from different types to establish a relationship between chemical composition and sensory evaluation to select types suitable for producing heated tobaccos. Nine tobacco types (K326, Yunyan 97, Cherry-red tobacco, Han tobacco, Dao tobacco, Tiandeng tobacco, Sun-cured yellow tobacco, fresh-cut tobacco, and aromatic tobacco) planted in Yunnan Province, China were selected. Their sensory quality was evaluated by the method for sensory evaluation of heated tobaccos and chemical composition and content of aroma substances in tobacco leaves were determined. In the evaluation of sensory quality of heated tobaccos, the total score of Tiandeng tobacco was significantly higher than those of the other types, followed by Cherry-red tobacco and K326; There were significant differences in chemical composition in the nine tobacco types and the total alkaloid content in Cherry-red tobacco was notably higher than in the other tobacco types. The amounts of total sugar, reducing sugar, and starch in Han tobacco were significantly lower than other types, while the amounts of total nitrogen, potassium oxide, chloride ions, and protein were much higher than in the other tobacco types. The total amounts of polyphenols and aroma compounds in fresh-cut tobacco were significantly higher than in the other tobacco types. The contents of nornicotine, neonicotine, anatabine, and total alkaloid showed a significant positive correlation with the total sensory evaluation score. The contents of nicotyrine and 2,3-bipyridine were significantly and negatively correlated with the total sensory evaluation score. A remarkable negative correlation was found between starch content and score on irritation. Furthermore, the amounts of neochlorogenic acid, chlorogenic acid, caffeic acid, and total polyphenols were significantly and positively correlated with the total sensory evaluation score. The amounts of aldehydes and phenolic compounds had a significant negative correlation, while the amount of olefin compounds had a significant positive correlation, with the total sensory evaluation score. These chemicals in tobacco leaves can be used as in analyses screening of other suitable tobacco types, and as reference standards for selecting tobacco raw materials suitable for high-quality heated tobaccos.

Temporal proteomic changes induced by nicotine in human cells: A quantitative proteomics approach

Nicotine is a prominent active compound in tobacco and many smoking cessation products. Some of the biological effects of nicotine are well documented in in vitro and in vivo systems; however, data are scarce concerning the time-dependent changes on protein and phosphorylation events in response to nicotine. Here, we profiled the proteomes of SH-SY5Y and A549 cell lines subjected to acute (15 min, 1 h and 4 h) or chronic (24 h, 48 h) nicotine exposures. We used sample multiplexing (TMTpro16) and quantified more than 9000 proteins and over 7000 phosphorylation events per cell line. Among our findings, we determined a decrease in mitochondrial protein abundance for SH-SY5Y, while we detected alterations in several immune pathways, such as the complement system, for A549 following nicotine treatment. We also explored the proposed association between smoking (specifically nicotine) and SARS-CoV2. Here, we found several host proteins known to interact with viral proteins that were affected by nicotine in a time dependent manner. This dataset can be mined further to investigate the potential role of nicotine in different biological contexts. SignificanceSmoking is a major public health issue that is associated with several serious chronic, yet preventable diseases, including stroke, heart disease, type 2 diabetes, cancer, and susceptibility to infection. Tobacco smoke is a complex mixture of thousands of different compounds, among which nicotine is the main addictive compound. The biological effects of nicotine have been reported in several models, however very little data are available concerning the temporal proteomic and phosphoproteomic changes in response to nicotine. Here, we provide a dataset exploring the potential role of nicotine on different biological processes over time, including implications in the study of SARS-CoV2.

The Role of CaMKII and ERK Signaling in Addiction.

Nicotine is the predominant addictive compound of tobacco and causes the acquisition of dependence through its interactions with nicotinic acetylcholine receptors and various neurotransmitter releases in the central nervous system. The Ca2+/calmodulin-dependent protein kinase II (CaMKII) and extracellular signal-regulated kinase (ERK) play a pivotal role in synaptic plasticity in the hippocampus. CaMKII is involved in long-term potentiation induction, which underlies the consolidation of learning and memory; however, the roles of CaMKII in nicotine and other psychostimulant-induced addiction still require further investigation. This article reviews the molecular mechanisms and crucial roles of CaMKII and ERK in nicotine and other stimulant drug-induced addiction. We also discuss dopamine (DA) receptor signaling involved in nicotine-induced addiction in the brain reward circuitry. In the last section, we introduce the association of polyunsaturated fatty acids and cellular chaperones of fatty acid-binding protein 3 in the context of nicotine-induced addiction in the mouse nucleus accumbens and provide a novel target for the treatment of drug abuse affecting dopaminergic systems.

Evaluation of Presence or Absence of α-Tocopherol and α-Tocopheryl Acetate in Various E-Liquids

Summary The presence of α-tocopheryl acetate in e-liquids is linked to EVALI (Electronic Cigarette, or Vaping, product use-Associated Lung Injuries). Typical e-liquids containing flavors and nicotine have a glycerin/propylene glycol carrier and are highly unlikely to contain α-tocopherol or α-tocopheryl acetate. However, the e-liquids containing cannabinoids, most notably tetrahydrocannabinol (THC), may contain α-tocopherol or α-tocopheryl acetate for enhancing the solubility of THC which is a lipophilic compound. For the analysis of α-tocopherol and of α-tocopheryl acetate in e-liquids a new HPLC technique was adopted which has been developed for the analysis of these compounds in tobacco and cigarette smoke and was previously reported. Both UV and MS/MS (MRM mode) were used as detection procedure. Thirty four e-liquids containing different levels of nicotine were evaluated using this method. None of the e-liquids contained either α-tocopherol or α-tocopheryl acetate. Also, three e-liquids containing cannabidiol (CBD) were analyzed. Two of the CBD containing liquids did not contain α-tocopherol or α-tocopheryl acetate. However, one of these e-liquids did contain α-tocopherol, but the level was low at about 10 μg/g, which is lower than the level of α-tocopherol per smoke of one cigarette (ISO smoking), and significantly lower than the level of α-tocopherol in tobacco.

Smoking Is Injurious to Pulp

Smoking is a worldwide menace that is harmful to health and casts its shadow on the dental pulp as well. Detrimental effects of nicotine and other tobacco compounds on the dental pulp may compromise diagnosis treatment outcome healing as well as regeneration. This article aims to highlight the negative influence of smoking on the dental pulp and its implications on dental procedures and its outcomes.

Specific genetic susceptibility patterns of the urothelial bladder cancer taxonomic subtypes

Introduction Urothelial bladder cancer (UBC) is a complex disease with diverse genetic and environmental factors participating and interacting in its development. There are evidences indicating that UBC is a heterogeneous disease, with molecular subtypes having been characterized. We aimed to identify the UBC genetic susceptibility patterns according to the UBC taxonomic subtypes. Methods Subjects came from the SBC/EPICURO case-control study. Paraffin embedded was used to assess immunohistochemical protein expression of KRT5/6, KRT14, FOXA1, and GATA3. Multiple imputation through chained equations was used to replace missing values. The marker quick-scores were measured and used in an unsupervised hierarchical cluster to define the UBC subtypes. Germline DNA was extracted from leukocytes and genotyped with Illumina HumanHap1M array. We analyzed the association between subtypes and genetic variants by applying multinomial logistic ENET with 350,084 SNPs that passed quality control filters. The SNPs specifically associated with each subtype were annotated as protein coding genes and GO biological processes using the FUMA GWAS platform. Results Three significant clusters of cases were identified: BASQ-like (8%), Luminal-like (64%) and Mixed (28%). ENET selected 2,888 SNPs differentially associated with the UBC subtypes: 274 SNPs associated with BASQ-like tumors and mainly annotated to GO Lipid Hydroxylation processes; 1654 SNPs associated with Luminal-like tumors and annotated to 24 different GO biological processes, including a phenol containing compound metabolic process involved in tobacco compounds metabolism; 960 SNPs associated with Mixed tumors and annotated to GO cornification processes. Conclusions Our results point to a specific genetic susceptibility background for each UBC subtypes. Artificial Intelligence approaches (ENET) has helped in delineating and better understanding of bladder cancer etiology.

The α5 Nicotinic Acetylcholine Receptor Subunit Differentially Modulates α4β2* and α3β4* Receptors.

Nicotine, the principal reinforcing compound in tobacco, acts in the brain by activating neuronal nicotinic acetylcholine receptors (nAChRs). This review summarizes our current knowledge regarding how the α5 accessory nAChR subunit, encoded by the CHRNA5 gene, differentially modulates α4β2* and α3β4* receptors at the cellular level. Genome-wide association studies have linked a gene cluster in chromosomal region 15q25 to increased susceptibility to nicotine addiction, lung cancer, chronic obstructive pulmonary disease, and peripheral arterial disease. Interestingly, this gene cluster contains a non-synonymous single-nucleotide polymorphism (SNP) in the human CHRNA5 gene, causing an aspartic acid (D) to asparagine (N) substitution at amino acid position 398 in the α5 nAChR subunit. Although other SNPs have been associated with tobacco smoking behavior, efforts have focused predominantly on the D398 and N398 variants in the α5 subunit. In recent years, significant progress has been made toward understanding the role that the α5 nAChR subunit—and the role of the D398 and N398 variants—plays on nAChR function at the cellular level. These insights stem primarily from a wide range of experimental models, including receptors expressed heterologously in Xenopus oocytes, various cell lines, and neurons derived from human induced pluripotent stem cells (iPSCs), as well as endogenous receptors in genetically engineered mice and—more recently—rats. Despite providing a wealth of available data, however, these studies have yielded conflicting results, and our understanding of the modulatory role that the α5 subunit plays remains incomplete. Here, we review these reports and the various techniques used for expression and analysis in order to examine how the α5 subunit modulates key functions in α4β2* and α3β4* receptors, including receptor trafficking, sensitivity, efficacy, and desensitization. In addition, we highlight the strikingly different role that the α5 subunit plays in Ca2+ signaling between α4β2* and α3β4* receptors, and we discuss whether the N398 α5 subunit variant can partially replace the D398 variant.

Analysis of α-Tocopherol in Tobacco and Cigarette Smoke

Summary α-Tocopherol, a type of vitamin E, has been known to be present in tobacco for many years. The compound is an antioxidant protecting cell membranes from oxidants. α-Tocopherol is transferred from tobacco into cigarette smoke, where it is also present. Analysis of α-tocopherol has been reported in a number of studies and in various matrices including tobacco and tobacco smoke. However, no recent publication describes a method for quantitative analysis of tocopherol in tobacco and in cigarette smoke, and many methods reported from previous studies were not published and only presented at conferences or communicated in internal company publications. The goal of this study was to quantitate α-tocopherol and, if present, α-tocopheryl acetate in tobacco and in tobacco smoke. For this analysis, an original HPLC technique was developed and is described in this report. Both UV and MS/MS (MRM mode) were used as detection procedure for the analysis. The results obtained using UV detection were in very good agreement with the results obtained using MS/MS detection. The method has been applied for the analysis of a number of tobaccos, as well as the total particulate matter (TPM) from cigarettes made with the same tobaccos. Depending on tobacco type, the levels of α-tocopherol vary in tobacco between about 200 μg/g up to about 900 μg/g (“dry weight basis”). For ISO type smoking, the levels of α-tocopherol vary in TPM between about 2 μg/mg up to slightly above 4 μg/mg of TPM. For a cigarette generating TPM of about 10 mg/cig, the α-tocopherol is between about 20 μg/cig up to about 40 μg/cig. A relatively good correlation was obtained between the level of α-tocopherol in smoke (ISO type smoking) and the level of the compound in tobacco. α-Tocopheryl acetate was absent in tobacco.