Anatabine lowers Alzheimer's Aβ production in vitro and in vivo

Improving Wastewater-Based Tobacco Use Estimates Using Anabasine

In wastewater-based epidemiology (WBE), nicotine metabolites have been used as biomarkers for monitoring tobacco use. Recently, the minor tobacco alkaloids anabasine and anatabine have been suggested as more specific biomarkers for tobacco use since nicotine use can be from both tobacco and non-tobacco sources. This study aimed to provide an in-depth evaluation of the suitability of anabasine and anatabine as WBE biomarkers of tobacco and subsequently estimate their excretion factors for WBE applications. Pooled urine (n = 64) and wastewater samples (n = 277), collected between 2009 and 2019 in Queensland, Australia, were analyzed for nicotine and its metabolites (cotinine and hydroxycotinine), as well as anabasine and anatabine. Anabasine performed as the better biomarker, showing a similar per capita load in pooled urine (2.2 ± 0.3 μg/day/person) and wastewater samples (2.3 ± 0.3 μg/day/person), while the per capita load of anatabine in wastewater was 50% higher than its load in urine. It is estimated that 0.9 μg of anabasine was excreted per cigarette smoked. Triangulation of tobacco sales data and tobacco use estimated from either anabasine or cotinine showed that anabasine-based estimates were 5% higher than sales data, while cotinine-based estimates were between 2 and 28% higher. Our results provided concrete evidence to confirm the suitability of anabasine as a specific biomarker for monitoring tobacco use by WBE.

Improving the Treatment Effect of Carotenoids on Alzheimer's Disease through Various Nano-Delivery Systems

Natural bioactive compounds have recently emerged as a current strategy for Alzheimer's disease treatment. Carotenoids, including astaxanthin, lycopene, lutein, fucoxanthin, crocin and others are natural pigments and antioxidants, and can be used to treat a variety of diseases, including Alzheimer's disease. However, carotenoids, as oil-soluble substances with additional unsaturated groups, suffer from low solubility, poor stability and poor bioavailability. Therefore, the preparation of various nano-drug delivery systems from carotenoids is a current measure to achieve efficient application of carotenoids. Different carotenoid delivery systems can improve the solubility, stability, permeability and bioavailability of carotenoids to a certain extent to achieve Alzheimer's disease efficacy. This review summarizes recent data on different carotenoid nano-drug delivery systems for the treatment of Alzheimer's disease, including polymer, lipid, inorganic and hybrid nano-drug delivery systems. These drug delivery systems have been shown to have a beneficial therapeutic effect on Alzheimer's disease to a certain extent.

Tobacco Alkaloid Assessment in a DSS-Induced Colitis Mouse Model with a Fully Humanized Immune System

Inflammatory bowel disease (IBD) refers to chronic intestinal immune-mediated diseases including two main disease manifestations: ulcerative colitis (UC) and Crohn’s disease (CD). Epidemiological, clinical, and preclinical evidence has highlighted the potential anti-inflammatory properties of naturally occurring alkaloids. In the present study, we investigated the potential anti-inflammatory activities of the tobacco alkaloids nicotine and anatabine in a dextran sulfate sodium (DSS)-induced UC mouse model with a fully humanized immune system. Our results show that nicotine significantly reduced all acute colitis symptoms and improved colitis-specific endpoints, including histopathologically assessed colon inflammation, tissue damage, and mononuclear cell infiltration. The tobacco alkaloid anatabine showed similar effectiveness trends, although they were generally weaker or not significant. Gene expression analysis in the context of biological network models of IBD further pinpointed a possible mechanism by which nicotine attenuated DSS-induced colitis in humanized mice. The current study enables further investigation of possible molecular mechanisms by which tobacco alkaloids attenuate UC symptoms.

BACE-1 Inhibitors Targeting Alzheimer's Disease

The accumulation of amyloid-β (Aβ) is the main event related to Alzheimer's disease (AD) progression. Over the years, several disease-modulating approaches have been reported, but without clinical success. The amyloid cascade hypothesis evolved and proposed essential targets such as tau protein aggregation and modulation of β-secretase (β-site amyloid precursor protein cleaving enzyme 1 - BACE-1) and γ-secretase proteases. BACE-1 cuts the amyloid precursor protein (APP) to release the C99 fragment, giving rise to several Aβ peptide species during the subsequent γ-secretase cleavage. In this way, BACE-1 has emerged as a clinically validated and attractive target in medicinal chemistry, as it plays a crucial role in the rate of Aβ generation. In this review, we report the main results of candidates in clinical trials such as E2609, MK8931, and AZD-3293, in addition to highlighting the pharmacokinetic and pharmacodynamic-related effects of the inhibitors already reported. The current status of developing new peptidomimetic, non-peptidomimetic, naturally occurring, and other class inhibitors are demonstrated, considering their main limitations and lessons learned. The goal is to provide a broad and complete approach to the subject, exploring new chemical classes and perspectives.

Systems biology reveals anatabine to be an NRF2 activator

Anatabine, an alkaloid present in plants of the Solanaceae family (including tobacco and eggplant), has been shown to ameliorate chronic inflammatory conditions in mouse models, such as Alzheimer’s disease, Hashimoto’s thyroiditis, multiple sclerosis, and intestinal inflammation. However, the mechanisms of action of anatabine remain unclear. To understand the impact of anatabine on cellular systems and identify the molecular pathways that are perturbed, we designed a study to examine the concentration-dependent effects of anatabine on various cell types by using a systems pharmacology approach. The resulting dataset, consisting of measurements of various omics data types at different time points, was analyzed by using multiple computational techniques. To identify concentration-dependent activated pathways, we performed linear modeling followed by gene set enrichment. To predict the functional partners of anatabine and the involved pathways, we harnessed the LINCS L1000 dataset’s wealth of information and implemented integer linear programming on directed graphs, respectively. Finally, we experimentally verified our key computational predictions. Using an appropriate luciferase reporter cell system, we were able to demonstrate that anatabine treatment results in NRF2 (nuclear factor-erythroid factor 2-related factor 2) translocation, and our systematic phosphoproteomic assays showed that anatabine treatment results in activation of MAPK signaling. While there are certain areas to be explored in deciphering the exact anti-inflammatory mechanisms of action of anatabine and other NRF2 activators, we believe that anatabine constitutes an interesting molecule for its therapeutic potential in NRF2-related diseases.

Anatabine attenuates ovalbumin-induced asthma via oxidative stress and inflammation mitigation and Nrf2/HO-1 signaling upregulation in rats

AIMS

Asthma affects a large number of people worldwide and is characterized by chronic allergic airway inflammation. Anatabine is a natural alkaloid that is structurally similar to nicotine and found in the Solanaceae family of plants, with anti-inflammatory properties. Consequently, this study aimed to evaluate the potential therapeutic effect of anatabine against asthma.

MAIN METHODS

Ovalbumin was used to induce asthma in rats. Two asthmatic groups were treated with low and high doses of anatabine.

KEY FINDINGS

Asthmatic animals experienced increased total leukocyte count and inflammatory cytokines in bronchoalveolar lavage fluid (BALF), bronchitis, and bronchopneumonia associated with mast cell infiltration. Additionally, inducible nitric oxide synthase immunostaining was observed, with decreased pulmonary antioxidant capacity and enzymes and decreased Nrf2 and HO-1 gene expression while increased NFκB-P65 expression. Interestingly, asthmatic animals treated with anatabine at both doses showed dose-dependently decreased inflammatory cells and cytokine levels within BALF reduced inflammation in the airways through decreased mast cell infiltration within lung tissues and increased antioxidant enzymes and Nrf2 and Ho-1 expression levels.

SIGNIFICANCE

Our results highlight the potential beneficial effect of anatabine against asthma through anti-inflammatory and antioxidant mechanisms. Therefore, anatabine is a promising candidate for pulmonary asthma treatment.

Selected Natural Products in Neuroprotective Strategies for Alzheimer's Disease-A Non-Systematic Review

Neurodegenerative disorders such as Alzheimer’s disease (AD) are distinguished by the irreversible degeneration of central nervous system function and structure. AD is characterized by several different neuropathologies—among others, it interferes with neuropsychiatrical controls and cognitive functions. This disease is the number one neurodegenerative disorder; however, its treatment options are few and, unfortunately, ineffective. In the new strategies devised for AD prevention and treatment, the application of plant-based natural products is especially popular due to lesser side effects associated with their taking. Moreover, their neuroprotective activities target different pathological mechanisms. The current review presents the anti-AD properties of several natural plant substances. The paper throws light on products under in vitro and in vivo trials and compiles information on their mechanism of actions. Knowledge of the properties of such plant compounds and their combinations will surely lead to discovering new potent medicines for the treatment of AD with lesser side effects than the currently available pharmacological proceedings.

Phytochemicals targeting NF-κB signaling: Potential anti-cancer interventions

Nuclear factor κB (NF-κB) is a ubiquitous regulator of the signalome and is indispensable for various biological cell functions. NF-κB consists of five transcription factors that execute both cytoplasmic and nuclear signaling processes in cells. NF-κB is the only signaling molecule that governs both pro- and anti-apoptotic, and pro- and anti-inflammatory responses. This is due to the canonical and non-canonical components of the NF-κB signaling pathway. Together, these pathways orchestrate cancer-related inflammation, hyperplasia, neoplasia, and metastasis. Non-canonical NF-κB pathways are particularly involved in the chemoresistance of cancer cells. In view of its pivotal role in cancer progression, NF-κB represents a potentially significant therapeutic target for modifying tumor cell behavior. Several phytochemicals are known to modulate NF-κB pathways through the stabilization of its inhibitor, IκB, by inhibiting phosphorylation and ubiquitination thereof. Several natural pharmacophores are known to inhibit the nuclear translocation of NF-κB and associated pro-inflammatory responses and cell survival pathways. In view of this and the high degree of specificity exhibited by various phytochemicals for the NF-κB component, we herein present an in-depth overview of these phytochemicals and discuss their mode of interaction with the NF-κB signaling pathways for controlling the fate of tumor cells for cancer-directed interventions.

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NF-κB plays a pivotal role in the maintenance of homeostasis and various inflammation-mediated pathologies.

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NF-κB is involved in cancer development and progression by modulating growth signaling and apoptosis pathways.

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Phytochemicals modulating NF-κB activity should be exploited to design anticancer drugs with minimal side effects.

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Use of these phytochemicals in adjunctive chemotherapy may enhance the chemosensitivity of existing chemotherapeutic drugs.

Anti-Alzheimer's Molecules Derived from Marine Life: Understanding Molecular Mechanisms and Therapeutic Potential

Alzheimer’s disease (AD) is a devastating neurodegenerative disease and the most common cause of dementia. It has been confirmed that the pathological processes that intervene in AD development are linked with oxidative damage to neurons, neuroinflammation, tau phosphorylation, amyloid beta (Aβ) aggregation, glutamate excitotoxicity, and cholinergic deficit. Still, there is no available therapy that can cure AD. Available therapies only manage some of the AD symptoms at the early stages of AD. Various studies have revealed that bioactive compounds derived from marine organisms and plants can exert neuroprotective activities with fewer adverse events, as compared with synthetic drugs. Furthermore, marine organisms have been identified as a source of novel compounds with therapeutic potential. Thus, there is a growing interest regarding bioactive compounds derived from marine sources that have anti-AD potentials. Various marine drugs including bryostatin-1, homotaurine, anabaseine and its derivative, rifampicins, anhydroexfoliamycin, undecylprodigioisin, gracilins, 13-desmethyl spirolide-C, and dictyostatin displayed excellent bioavailability and efficacy against AD. Most of these marine drugs were found to be well-tolerated in AD patients, along with no significant drug-associated adverse events. In this review, we focus on the drugs derived from marine life that can be useful in AD treatment and also summarize the therapeutic agents that are currently used to treat AD.

In Vivo Profiling of a Natural Alkaloid, Anatabine, in Rodents: Pharmacokinetics and Anti-Inflammatory Efficacy

Natural alkaloids, a large class of plant-derived substances, have attracted considerable interest because of their pharmacological activities. In this study, the in vivo pharmacokinetics and anti-inflammatory profile of anatabine, a naturally occurring alkaloid, were characterized in rodents. Anatabine was found to be bioavailable and brain-penetrant following systemic administration. Following intraperitoneal (i.p.) administration (1, 2, and 5 mg/kg), anatabine caused a dose-dependent reduction in carrageenan-induced paw edema in rats; in mice, it inhibited the production of pro-inflammatory cytokines and simultaneously elevated the levels of an anti-inflammatory cytokine in a dose-dependent manner 2 h after lipopolysaccharide challenge. Furthermore, anatabine (∼10 and ∼20 mg/kg/day for 4 weeks; inhalation exposure) had effects in a murine model of multiple sclerosis, reducing neurological deficits and bodyweight loss. Comparative studies of the pharmacokinetics and anti-inflammatory activity of anatabine demonstrated its bioequivalence in rats following i.p. administration and inhalation exposure. This study not only provides the first detailed profile of anatabine pharmacokinetics in rodents but also comprehensively characterizes the anti-inflammatory activities of anatabine in acute and chronic inflammatory models. These findings provide a basis for further characterizing and optimizing the anti-inflammatory properties of anatabine.

Ginkgolide B‑induced AMPK pathway activation protects astrocytes by regulating endoplasmic reticulum stress, oxidative stress and energy metabolism induced by Aβ1‑42

Ginkgolide B (GB), the diterpenoid lactone compound isolated from the extracts of Ginkgo biloba leaves, significantly improves cognitive impairment, but its potential pharmacological effect on astrocytes induced by β-amyloid (Aβ)_1-42 remains to be elucidated. The present study aimed to investigate the protective effect and mechanism of GB on astrocytes with Aβ_1-42-induced apoptosis in Alzheimer's disease (AD). Astrocytes obtained from Sprague Dawley rats were randomly divided into control, Aβ, GB and GB + compound C groups. Cell viability and apoptosis were analyzed using Cell Counting Kit-8 and flow cytometry assays, respectively. Protein and mRNA expression levels were analyzed using western blotting and reverse transcription-quantitative PCR, respectively. The levels of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), reactive oxygen species (ROS) and ATP were determined using the corresponding commercial kits. The findings revealed that GB attenuated Aβ_1-42-induced apoptosis and the 5′ adenosine monophosphate- activated protein kinase (AMPK) inhibitor compound C reversed the protective effects of GB. In addition, GB reversed Aβ_1-42-induced oxidative damage and energy metabolism disorders, including decreases in the levels of SOD, GSH-Px and ATP and increased the levels of MDA and ROS in astrocytes, while compound C reversed the anti-oxidative effect and the involvement of GB in maintaining energy metabolism in astrocytes. Finally, GB decreased the expression levels of the endoplasmic reticulum stress (ERS) proteins and the apoptotic protein CHOP and increased both mRNA and protein expression of the components of the energy metabolism-related AMPK/peroxisome proliferator-activated receptor γ coactivator 1α/peroxisome proliferator-activated receptor α and anti-oxidation-related nuclear respiratory factor 2/heme oxygenase 1/NAD(P)H dehydrogenase (quinone 1) pathways and downregulated the expression of β-secretase 1. However, compound C could antagonize these effects. In conclusion, the findings demonstrated that GB protected against Aβ_1-42-induced apoptosis by inhibiting ERS, oxidative stress, energy metabolism disorders and Aβ_1-42 production probably by activating AMPK signaling pathways. The findings provided an innovative insight into the treatment using GB as a therapeutic in Aβ_1-42-related AD.

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.

Pyridine alkaloids with activity in the central nervous system

This review discusses all pyridine alkaloids with CNS activity, their therapeutic potential, and the interesting array of sources whence they originate.

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

Background

Inflammatory 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.

Results

Oral 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.

Conclusions

Our 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.

A Pharmacological Comparison of Two Isomeric Nicotinic Receptor Agonists: The Marine Toxin Isoanatabine and the Tobacco Alkaloid Anatabine

Many organisms possess "secondary" compounds to avoid consumption or to immobilize prey. While the most abundant or active compounds are initially investigated, more extensive analyses reveal other "minor" compounds with distinctive properties that may also be of biomedical and pharmaceutical significance. Here, we present an initial in vitro investigation of the actions of two isomeric tetrahydropyridyl ring-containing anabasine analogs: isoanatabine, an alkaloid isolated from a marine worm, and anatabine, a relatively abundant minor alkaloid in commercial tobacco plants. Both compounds have a double bond that is distal to the piperidine ring nitrogen of anabasine. Racemic isoanatabine and anatabine were synthesized and their S- and R-enantiomers were isolated by chiral high pressure liquid chromatography (HPLC). Both isoanatabines displayed higher efficacies at α4β2 nicotinic acetylcholine receptors (nAChRs) relative to the anatabines; R-isoanatabine was most potent. Radioligand binding experiments revealed similar α4β2 nAChR binding affinities for the isoanatabines, but R-anatabine affinity was twice that of S-anatabine. While the two anatabines and S-isoanatabine were highly efficacious agonists at α7 nAChRs, R-isoanatabine was only a weak partial agonist. The four compounds share an ability to stimulate both α4β2 and α7 nAChRs, a property that may be useful in developing more efficacious drugs to treat neurodegenerative and other medical disorders.

Neurobehavioral effects of selected tobacco constituents in rodents following subchronic administration

Bidirectional correlations between cigarette smoking and affective disorders, such as depression, anxiety, and schizophrenia, are well documented. These findings have led to substantial investigations into the effects of the major tobacco alkaloid, nicotine, and to a lesser extent, of other tobacco constituents, on the central nervous system (CNS). However, systematic profiling of the neuropharmacological effects of tobacco constituents is limited. To elucidate the effects of selected tobacco constituents on the CNS, we used the SmartCube® system, which captures and classifies behavioral features of compound-treated mice, to profile the psychiatric drugs-like properties of previously reported neuroactive tobacco compounds in mice. Daily intraperitoneal injection of nicotine (0.5 and 1 mg/kg/day) and anatabine (5 mg/kg/day) for 7 days produced antidepressant-like behavioral SmartCube® signatures in mice, and these results were supported by the improved active coping responses in the forced swim tests. Conversely, ferulic acid did not show any identifiable class signatures in the SmartCube® tests, but rather displayed subclass signatures associated with acetylcholinesterase inhibitors. In novel object recognition memory test in rats, ferulic acid improved memory after 7 days of subcutaneous injection at 0.3 or 3 mg/kg/day. These results support previous findings showing the antidepressant drug-like effects of nicotine and the nootropic effects of ferulic acid. This is also the first report on the antidepressant drug-like effects of anatabine in rodents. This study provides a systemic behavioral evaluation of tobacco alkaloids and further insights into the association between affective disorders and smoking incidence.

Macroalgae as a Valuable Source of Naturally Occurring Bioactive Compounds for the Treatment of Alzheimer's Disease

Alzheimer's disease (AD) is a neurological condition that affects mostly aged individuals. Evidence suggests that pathological mechanisms involved in the development of AD are associated with cholinergic deficit, glutamate excitotoxicity, beta-amyloid aggregation, tau phosphorylation, neuro-inflammation, and oxidative damage to neurons. Currently there is no cure for AD; however, synthetic therapies have been developed to effectively manage some of the symptoms at the early stage of the disease. Natural products from plants and marine organisms have been identified as important sources of bioactive compounds with neuroprotective potentials and less adverse effects compared to synthetic agents. Seaweeds contain several kinds of secondary metabolites such as phlorotannins, carotenoids, sterols, fucoidans, and poly unsaturated fatty acids. However, their neuroprotective effects and mechanisms of action have not been fully explored. This review discusses recent investigations and/or updates on interactions of bioactive compounds from seaweeds with biomarkers involved in the pathogenesis of AD using reports in electronic databases such as Web of science, Scopus, PubMed, Science direct, Scifinder, Taylor and Francis, Wiley, Springer, and Google scholar between 2015 and 2019. Phlorotannins, fucoidans, sterols, and carotenoids showed strong neuroprotective potentials in different experimental models. However, there are no data from human studies and/or clinical trials.

Distinct Signaling Pathways Regulate TREM2 Phagocytic and NFκB Antagonistic Activities

Several genetic variants of the Triggering Receptor Expressed on Myeloid Cells-2 (TREM2) have been shown to increase the risk of developing Alzheimer’s disease (AD) supporting a role of microglia and immune cells in the pathobiology of AD. We have employed an ectopic model of TREM2 and DAP12 expression in HEK293 cells to study selectively TREM2 dependent signaling and phagocytic functions and evaluated the effects of some of the TREM2 mutations associated with AD. We show that shedding of the TREM2 N-terminal domain does not affect the inhibition of NFκB activation induced by TREM2 while it completely blocks phagocytosis suggesting that TREM2 anti-inflammatory properties can be mediated by the TREM2 C-terminal fragment while the phagocytic activity requires the full-length receptor. In addition, we confirm in that model that apolipoprotein E (APOE) is a ligand for TREM2 and triggers TREM2 signaling. In particular, we show that APOE4 stimulates spleen tyrosine kinase (SYK) activation more potently than APOE2 in a TREM2 dependent manner. Interestingly, TREM2 appears to antagonize NFκB activation induced by phorbol ester but is unable to prevent TNFα induction of NFκB activation suggesting that TREM2 antagonizes inflammatory events triggered downstream of PKC. TREM2 mutations drastically impact TREM2 phagocytosis as well as its ability to antagonize NFκB activation and notably prevent the activation of the PI3K/AKT pathway observed with wild-type TREM2. Overall our data suggest that TREM2 dependent phagocytosis requires an activation of the SYK/PI3K/AKT/PLCγ pathways while the suppression of NFκB activation by TREM2 is independent of SYK, PI3K, and PLCγ activities. This model of ectopic TREM2-DAP12 co-expression appears suitable to study TREM2 signaling as several biological functions of TREM2 and TREM2 mutations that have been previously described in myeloid and microglial cells were also replicated in this model.

GTS-21 has cell-specific anti-inflammatory effects independent of α7 nicotinic acetylcholine receptors

α7 Nicotinic acetylcholine receptors (nAChRs) reportedly reduce inflammation by blocking effects of the important pro-inflammatory transcription factor, nuclear factor kappa-light chain-enhancer of B cells (NFκB). The α7 nAChR partial agonist GTS-21 reduces secretion of pro-inflammatory cytokines including interleukin-6 (IL6) and tumor-necrosis factor (TNF) in models of endotoxemia and sepsis, and its anti-inflammatory effects are widely ascribed to α7 nAChR activation. However, mechanistic details of α7 nAChR involvement in GTS-21 effects on inflammatory pathways remain unclear. Here, we investigate how GTS-21 acts in two cell systems including the non-immune rat pituitary cell line GH4C1 expressing an NFκB-driven reporter gene and cytokine secretion by ex vivo cultures of primary mouse macrophages activated by lipopolysaccharide (LPS). GTS-21 does not change TNF-stimulated NFκB signaling in GH4C1 cells expressing rat α7 nAChRs, suggesting that GTS-21 requires additional unidentified factors besides α7 nAChR expression to allow anti-inflammatory effects in these cells. In contrast, GTS-21 dose-dependently suppresses LPS-induced IL6 and TNF secretion in primary mouse macrophages endogenously expressing α7 nAChRs. GTS-21 also blocks TNF-induced phosphorylation of NFκB inhibitor alpha (IκBα), an important intermediary in NFκB signaling. However, α7 antagonists methyllycaconitine and α-bungarotoxin only partially reverse GTS-21 blockade of IL6 and TNF secretion. Further, GTS-21 significantly inhibited LPS-induced IL6 and TNF secretion in macrophages isolated from knockout mice lacking α7 nAChRs. These data indicate that even though a discrete component of the anti-inflammatory effects of GTS-21 requires expression of α7 nAChRs in macrophages, GTS-21 also has anti-inflammatory effects independent of these receptors depending on the cellular context.

Recent Expansions on Cellular Models to Uncover the Scientific Barriers Towards Drug Development for Alzheimer's Disease

Globally, the central nervous system (CNS) disorders appear as the most critical pathological threat with no proper cure. Alzheimer's disease (AD) is one such condition frequently observed with the aged population and sometimes in youth too. Most of the research utilizes different animal models for in vivo study of AD pathophysiology and to investigate the potency of the newly developed therapy. These in vivo models undoubtably provide a powerful investigation tool to study human brain. Although, it sometime fails to mimic the exact environment and responses as the human brain owing to the distinctive genetic and anatomical features of human and rodent brain. In such condition, the in vitro cell model derived from patient specific cell or human cell lines can recapitulate the human brain environment. In addition, the frequent use of animals in research increases the cost of study and creates various ethical issues. Instead, the use of in vitro cellular models along with animal models can enhance the translational values of in vivo models and represent a better and effective mean to investigate the potency of therapeutics. This strategy also limits the excessive use of laboratory animal during the drug development process. Generally, the in vitro cell lines are cultured from AD rat brain endothelial cells, the rodent models, human astrocytes, human brain capillary endothelial cells, patient derived iPSCs (induced pluripotent stem cells) and also from the non-neuronal cells. During the literature review process, we observed that there are very few reviews available which describe the significance and characteristics of in vitro cell lines, for AD investigation. Thus, in the present review article, we have compiled the various in vitro cell lines used in AD investigation including HBMEC, BCECs, SHSY-5Y, hCMEC/D3, PC-2 cell line, bEND3 cells, HEK293, hNPCs, RBE4 cells, SK-N-MC, BMVECs, CALU-3, 7W CHO, iPSCs and cerebral organoids cell lines and different types of culture media such as SCM, EMEM, DMEM/F12, RPMI, EBM and 3D-cell culture.

Loss of Smooth Muscle α-Actin Leads to NF-κB-Dependent Increased Sensitivity to Angiotensin II in Smooth Muscle Cells and Aortic Enlargement

RATIONALE

Mutations in ACTA2, encoding the smooth muscle isoform of α-actin, cause thoracic aortic aneurysms, acute aortic dissections, and occlusive vascular diseases.

OBJECTIVE

We sought to identify the mechanism by which loss of smooth muscle α-actin causes aortic disease.

METHODS AND RESULTS

Acta2^-/- mice have an increased number of elastic lamellae in the ascending aorta and progressive aortic root dilation as assessed by echocardiography that can be attenuated by treatment with losartan, an angiotensin II (AngII) type 1 receptor blocker. AngII levels are not increased in Acta2^-/- aortas or kidneys. Aortic tissue and explanted smooth muscle cells from Acta2^-/- aortas show increased production of reactive oxygen species and increased basal nuclear factor κB signaling, leading to an increase in the expression of the AngII receptor type I a and activation of signaling at 100-fold lower levels of AngII in the mutant compared with wild-type cells. Furthermore, disruption of smooth muscle α-actin filaments in wild-type smooth muscle cells by various mechanisms activates nuclear factor κB signaling and increases expression of AngII receptor type I a.

CONCLUSIONS

These findings reveal that disruption of smooth muscle α-actin filaments in smooth muscle cells increases reactive oxygen species levels, activates nuclear factor κB signaling, and increases AngII receptor type I a expression, thus potentiating AngII signaling in vascular smooth muscle cells without an increase in the exogenous levels of AngII.

Acute or Delayed Treatment with Anatabine Improves Spatial Memory and Reduces Pathological Sequelae at Late Time-Points after Repetitive Mild Traumatic Brain Injury

Traumatic brain injury (TBI) has chronic and long-term consequences for which there are currently no approved pharmacological treatments. We have previously characterized the chronic neurobehavioral and pathological sequelae of a mouse model of repetitive mild TBI (r-mTBI) through to 2 years post-TBI. Despite the mild nature of the initial insult, secondary injury processes are initiated that involve neuroinflammatory and neurodegenerative pathways persisting and progressing for weeks and months post-injury and providing a potential window of opportunity for therapeutic intervention. In this study we examined the efficacy of a novel anti-inflammatory compound, anatabine, in modifying outcome after TBI. Our model of r-mTBI involves a series of five mild impacts (midline impact at 5 m/sec, 1 mm strike depth, 200 msec dwell time) with an interval of 48 h. Anatabine treatment was administered starting 30 min after injury and was delivered continuously through drinking water. At 6 months after TBI, anatabine treatment improved spatial memory in injured mice. Nine months after TBI, a cohort of mice was euthanized for pathological analysis that revealed reductions in astroglial (glial fibrillary acid protein, GFAP) and microglial (ionized calcium-binding adapter molecule 1, IBA1) responses in treated, injured animals. Treatments for the remaining mice were then crossed-over to assess the effects of late treatment administration and the effects of treatment termination. Nine months following crossover the remaining mice showed no effect of injury on their spatial memory, and whereas pathological analysis showed improvements in mice that had received delayed treatment, corpus callosum IBA1 increased in post-crossover placebo r-mTBI mice. These data demonstrate efficacy of both early and late initiation of treatment with anatabine in improving long term behavioral and pathology outcomes after mild TBI. Future studies will characterize the treatment window, the time course of treatment needed, and the dose needed to achieve therapeutic levels of anatabine in humans after injury.

Monitoring of anatabine release by methyl jasmonate elicited BY-2 cells using surface-enhanced Raman scattering

A new application of surface-enhanced Raman scattering (SERS) in the field of plant material analysis is proposed in this study. The aim was to monitor the release of anatabine by methyl jasmonate (MeJa) elicited Bright Yellow-2 (BY-2) cells. Gold nanoparticles (AuNps) were used as SERS substrate. The first step was to study the SERS activity of anatabine in a complex matrix comprising the culture medium and BY-2 cells. The second step was the calibration. This one was successfully performed directly in the culture medium in order to take into account the matrix effect, by spiking the medium with different concentrations of anatabine, leading to solutions ranging from 250 to 5000µgL(-1). A univariate analysis was performed, the intensity of a band situated at 1028cm(-1), related to anatabine, was plotted against the anatabine concentration. A linear relationship was observed with a R(2) of 0.9951. During the monitoring study, after the MeJa elicitation, samples were collected from the culture medium containing BY-2 cells at 0, 24h, 48h, 72h and 96h and were analysed using SERS. Finally, the amount of anatabine released in the culture medium was determined using the response function, reaching a plateau after 72h of 82µg of anatabine released/g of fresh weight (FW) MeJa elicited BY-2 cells.

Chronic Anatabine Treatment Reduces Alzheimer's Disease (AD)-Like Pathology and Improves Socio-Behavioral Deficits in a Transgenic Mouse Model of AD

Anatabine is a minor tobacco alkaloid, which is also found in plants of the Solanaceae family and displays a chemical structure similarity with nicotine. We have shown previously that anatabine displays some anti-inflammatory properties and reduces microgliosis and tau phosphorylation in a pure mouse model of tauopathy. We therefore investigated the effects of a chronic oral treatment with anatabine in a transgenic mouse model (Tg PS1/APPswe) of Alzheimer's disease (AD) which displays pathological Aβ deposits, neuroinflammation and behavioral deficits. In the elevated plus maze, Tg PS1/APPswe mice exhibited hyperactivity and disinhibition compared to wild-type mice. Six and a half months of chronic oral anatabine treatment, suppressed hyperactivity and disinhibition in Tg PS1/APPswe mice compared to Tg PS1/APPswe receiving regular drinking water. Tg PS1/APPswe mice also elicited profound social interaction and social memory deficits, which were both alleviated by the anatabine treatment. We found that anatabine reduces the activation of STAT3 and NFκB in the vicinity of Aβ deposits in Tg PS1/APPswe mice resulting in a reduction of the expression of some of their target genes including Bace1, iNOS and Cox-2. In addition, a significant reduction in microgliosis and pathological deposition of Aβ was observed in the brain of Tg PS1/APPswe mice treated with anatabine. This is the first study to investigate the impact of chronic anatabine treatment on AD-like pathology and behavior in a transgenic mouse model of AD. Overall, our data show that anatabine reduces β-amyloidosis, neuroinflammation and alleviates some behavioral deficits in Tg PS1/APPswe, supporting further exploration of anatabine as a possible disease modifying agent for the treatment of AD.

The spleen tyrosine kinase (Syk) regulates Alzheimer amyloid-β production and Tau hyperphosphorylation

We have previously shown that the L-type calcium channel (LCC) antagonist nilvadipine reduces brain amyloid-β (Aβ) accumulation by affecting both Aβ production and Aβ clearance across the blood-brain barrier (BBB). Nilvadipine consists of a mixture of two enantiomers, (+)-nilvadipine and (-)-nilvadipine, in equal proportion. (+)-Nilvadipine is the active enantiomer responsible for the inhibition of LCC, whereas (-)-nilvadipine is considered inactive. Both nilvadipine enantiomers inhibit Aβ production and improve the clearance of Aβ across the BBB showing that these effects are not related to LCC inhibition. In addition, treatment of P301S mutant human Tau transgenic mice (transgenic Tau P301S) with (-)-nilvadipine reduces Tau hyperphosphorylation at several Alzheimer disease (AD) pertinent epitopes. A search for the mechanism of action of (-)-nilvadipine revealed that this compound inhibits the spleen tyrosine kinase (Syk). We further validated Syk as a target-regulating Aβ by showing that pharmacological inhibition of Syk or down-regulation of Syk expression reduces Aβ production and increases the clearance of Aβ across the BBB mimicking (-)-nilvadipine effects. Moreover, treatment of transgenic mice overexpressing Aβ and transgenic Tau P301S mice with a selective Syk inhibitor respectively decreased brain Aβ accumulation and Tau hyperphosphorylation at multiple AD relevant epitopes. We show that Syk inhibition induces an increased phosphorylation of the inhibitory Ser-9 residue of glycogen synthase kinase-3β, a primary Tau kinase involved in Tau phosphorylation, by activating protein kinase A, providing a mechanism explaining the reduction of Tau phosphorylation at GSK3β-dependent epitopes following Syk inhibition. Altogether our data highlight Syk as a promising target for preventing both Aβ accumulation and Tau hyperphosphorylation in AD.

Effects of anatabine and unilateral maximal eccentric isokinetic muscle actions on serum markers of muscle damage and inflammation

The purpose of this study was to examine the effects of anatabine supplementation in conjunction with unilateral, maximal eccentric isokinetic muscle actions on serum markers of muscle damage and pro-inflammatory cytokines in humans. Seventeen men (mean ± S.D. age = 22.4 ± 3.2 yrs) participated in this double-blinded, placebo-controlled, crossover study. Participants were randomly assigned to two 10-day conditions (anatabine and placebo) separated by a 2-4 week washout period. After seven days of supplementation, blood was sampled immediately prior to PRE, immediately following POST, and 24, 48, and 72 h after 6 sets of 10 repetitions of unilateral, maximal eccentric isokinetic forearm flexion exercise. Concentrations of serum creatine kinase, lactate dehydrogenase, myoglobin, high sensitivity c-reactive protein, and TNF-α were measured. Creatine kinase, myoglobin, and lactate dehydrogenase increased (P<0.05), while high sensitivity c-reactive protein and TNF-α did not change (P>0.05) after the eccentric exercise during both conditions. Lactate dehydrogenase was higher (P<0.05) during the anatabine condition. The primary findings of this study were two-fold: (a) anatabine had no beneficial effects on traditional markers of muscle damage (creatine kinase, lactate dehydrogenase, and myoglobin) compared to placebo after the eccentric exercise protocol, and (b) the eccentric exercise protocol did not elicit increase in the pro-inflammatory cytokines (c-reactive protein and TNF-α). Future studies are needed to examine the effects of anatabine on naturally-occurring inflammation that is common with aging or obesity. Furthermore, additional research is needed to examine the relationship between muscle damage and inflammation after eccentric exercises of different modes, durations, and intensities.

Anatabine supplementation decreases thyroglobulin antibodies in patients with chronic lymphocytic autoimmune (Hashimoto's) thyroiditis: a randomized controlled clinical trial

CONTEXT

Hashimoto's thyroiditis is less prevalent in tobacco smokers. Anatabine, an alkaloid found in Solanaceae plants including tobacco, has been reported to ameliorate a mouse model of Hashimoto's thyroiditis.

OBJECTIVE

The effects of anatabine in patients with Hashimoto's thyroiditis were studied.

DESIGN, SETTING, PATIENTS, AND INTERVENTION

This was a double-blind, randomized, placebo-controlled multisite study. A total of 146 patients (70 treated with anatabine and 76 with placebo) completed the study. Approximately 50% of patients in each group were taking levothyroxine. Anatabine lozenges (9-24 mg/d) or placebo, each containing vitamins A and D3, were administered orally 3 times a day for 3 months.

MAIN OUTCOME MEASURES

Serum thyroperoxidase antibody (TPOAb) and thyroglobulin antibody (TgAb) levels were assessed. Safety was assessed through adverse events, clinical laboratory evaluations, and vital sign measurements.

RESULTS

Anatabine-treated patients had a significant reduction in absolute serum TgAb levels from baseline by study end relative to those receiving placebo (P=.027); however, there were no significant changes or differences in treatment group means for TPOAb or TgAb levels. Mean±SD TgAb values decreased by 46.2±101.1 and 3.9±83.9 World Health Organization units for the anatabine and placebo groups, respectively. Significantly more patients had a >20% drop in TgAb levels in the anatabine than placebo group (P=.023). Overall, the anatabine supplement was safe and well tolerated, although significantly (P<.05) more patients in the anatabine group reported adverse events.

CONCLUSIONS

These results demonstrate an immunological effect of anatabine on TgAb levels. Further studies are warranted to determine the longer-term effects and possible actions of anatabine on the course of Hashimoto's thyroiditis.

Effects of a facial cream containing the minor alkaloid anatabine on improving the appearance of the skin in mild to moderate rosacea: an open-label case series study

Background

Current medical and scientific research indicates that rosacea, a chronic and often debilitating skin condition that primarily affects the central face, may be caused by an overactive or excessive inflammatory immune response. Regardless of etiology, the accompanying redness and inflammation is unsightly and difficult for the patient. Anatabine is an alkaloid from the plant family Solanaceae that has been shown in several preclinical studies to modulate proinflammatory signaling pathways.

Objective

A cream containing anatabine was developed and evaluated in an open-label case series study for safety and effects on the appearance of the skin in 10 patients with mild to moderate rosacea.

Methods

Patients applied the cream to the face twice daily for a period of 30 days. Patients and the study physician completed safety and efficacy assessments at study end.

Results

Results showed that 50% of the patients self-reported improvement in the appearance of their skin, and the physician noted improvement in 70% of the patients. Photographs taken before and after 30 days of cream use provide visual evidence of the improvement in several patients. There were no complications or adverse events reported by any of the patients in the study, indicating that the anatabine cream was safe and very well tolerated.

Conclusion

The results of this open-label case series show that a facial cream containing anatabine can improve the appearance of the skin in patients with mild to moderate rosacea and suggest that a double-blind, vehicle-controlled trial in a larger number of subjects is warranted.

Effects of dietary supplementation with the solanaceae plant alkaloid anatabine on joint pain and stiffness: results from an internet-based survey study

Anatabine is a Solanaceae plant family alkaloid marketed in the United States as a dietary supplement. It has demonstrated anti-inflammatory effects in vivo and in vitro, and may be useful for musculoskeletal aches and pains. The purpose of this internet-based survey study was to provide more information about anatabine users who report benefits for joint pain or stiffness. Of the 282 survey respondents, 232 (82%) reported a benefit from anatabine supplementation for one or more joint pain conditions, most commonly the knee, wrists/hands/fingers, shoulder, and back, most often due to osteoarthritis or injury to the joint. Mean scores of joint pain and stiffness were significantly (P < 0.0001) reduced after starting anatabine supplementation, and for most respondents joint pain was virtually eliminated. Around 90% of all individuals rated the effect of anatabine supplementation as good or excellent for joint pain, stiffness, functionality, and overall effects. These results provide evidence that anatabine supplementation can lead to substantial improvement of musculoskeletal aches, pains, and stiffness, and can provide benefits in some individuals for various medical conditions in multiple joint locations.

The effects of anatabine on non-invasive indicators of muscle damage: a randomized, double-blind, placebo-controlled, crossover study

Background

Anatabine (ANA), a minor tobacco alkaloid found in the Solanaceae family of plants, may exhibit anti-inflammatory activity, which may be useful to aid in recovery from exercise-induced muscle damage. The purpose of this study, therefore, was to examine the effects of ANA supplementation on the recovery of isometric strength and selected non-invasive indicators of muscle damage.

Methods

A double-blinded, placebo-controlled, crossover design was used to study eighteen men (mean ± SD age = 22.2 ± 3.1 yrs; body mass = 80.3 ± 15.7 kg) who participated in two randomly-ordered conditions separated by a washout period. The ANA condition consisted of consuming 6–12 mg anatabine per day for 10 days, while testing took place during days 7–10. The placebo (PLA) condition was identical except that the PLA supplement contained no ANA. Maximal voluntary isometric peak torque (PT) of the forearm flexors, arm circumference, hanging joint angle, and subjective pain ratings were measured before (PRE), immediately after (POST), and 24, 48, and 72 h after six sets of 10 maximal, eccentric isokinetic forearm flexion muscle actions. Resting heart rate and blood pressure were measured at PRE and 72 h in each condition.

Results

For PT, hanging joint angle, arm circumference, and subjective pain ratings, there were no condition x time (p > 0.05) interactions, there were no main effects for condition (p > 0.05), but there were main effects for time (p < 0.001). There were no condition x time (p > 0.05) interactions and no main effects for condition (p > 0.05) or time (p > 0.05) for blood pressure or resting heart rate.

Conclusions

ANA supplementation had no effect on the recovery of muscle strength, hanging joint angle, arm swelling, or subjective pain ratings after a bout of maximal eccentric exercise in the forearm flexors. Therefore, ANA may not be beneficial for those seeking to improve recovery from heavy eccentric exercise. Future studies should examine the effects of ANA on the pro-inflammatory cytokine responses to exercise-induced muscle damage and the chronic low-grade inflammation observed in obese and elderly individuals.

Nicotine from edible Solanaceae and risk of Parkinson disease

OBJECTIVE

To test whether risk of Parkinson disease (PD) is associated with consumption of nicotine-containing edibles from the same botanical family as tobacco, Solanaceae, including peppers, tomatoes, and potatoes.

METHODS

In a population-based study with 490 newly diagnosed idiopathic PD cases diagnosed during 1992-2008 at the University of Washington Neurology Clinic or Group Health Cooperative in western Washington State and 644 unrelated, neurologically normal controls, we examined whether PD was associated with self-reported typical frequency of consumption of peppers, tomatoes, tomato juice, and potatoes during adulthood, while adjusting for consumption of other vegetables, age, sex, race/ethnicity, tobacco use, and caffeine.

RESULTS

PD was inversely associated with consumption of all edible Solanaceae combined (relative risk [RR] = 0.81, 95% confidence interval [CI] = 0.65-1.01 per time per day), but not consumption of all other vegetables combined (RR = 1.00, 95% CI = 0.92-1.10). The trend strengthened when we weighted edible Solanaceae by nicotine concentration (ptrend = 0.004). An inverse association was also evident for peppers specifically (ptrend = 0.005). The potentially protective effect of edible Solanaceae largely occurred in men and women who had never used tobacco or who had smoked cigarettes < 10 years.

INTERPRETATION

Dietary nicotine or other constituents of tobacco and peppers may reduce PD risk. However, confirmation and extension of these findings are needed to strengthen causal inferences that could suggest possible dietary or pharmaceutical interventions for PD prevention.

Antimalarial drug artemisinin extenuates amyloidogenesis and neuroinflammation in APPswe/PS1dE9 transgenic mice via inhibition of nuclear factor-κB and NLRP3 inflammasome activation

BACKGROUND

The activation of nuclear factor-kappa B (NF-κB) and NLRP3 inflammasome is involved in neuroinflammation, which is closely linked to Alzheimer's disease (AD). In vivo and in vitro studies have suggested that artemisinin shows antiinflammatory effects in inflammation-related diseases. However, the impacts of artemisinin on AD have not been investigated.

AIMS

In this study, 5-month-old APPswe/PS1dE9 transgenic mice were treated daily with 40 mg/kg artemisinin for 30 days by intraperitoneal injection to evaluate the effects of artemisinin on AD.

RESULTS

We found that artemisinin treatment (1) decreased neuritic plaque burden; (2) did not alter Aβ transport across the blood-brain barrier; (3) regulated APP processing via inhibiting β-secretase activity; (4) inhibited NF-κB activity and NALP3 inflammasome activation in APPswe/PS1dE9 double transgenic mice.

CONCLUSIONS

The in vivo study clearly demonstrates that artemisinin has protective effects on AD pathology due to its effects on suppressing NF-κB activity and NALP3 inflammasome activation. Our study suggests that targeting NF-κB activity and NALP3 inflammasome activation offers a valuable intervention for AD.

Amelioration of experimental autoimmune encephalomyelitis by anatabine

Anatabine, a naturally occurring alkaloid, is becoming a commonly used human food supplement, taken for its claimed anti-inflammatory properties although this has not yet been reported in human clinical trials. We have previously shown that anatabine does display certain anti-inflammatory properties and readily crosses the blood-brain barrier suggesting it could represent an important compound for mitigating neuro-inflammatory conditions. The present study was designed to determine whether anatabine had beneficial effects on the development of experimental autoimmune encephalomyelitis (EAE) in mice and to precisely determine its underlying mechanism of action in this mouse model of multiple sclerosis (MS). We found that orally administered anatabine markedly suppressed neurological deficits associated with EAE. Analyses of cytokine production in the periphery of the animals revealed that anatabine significantly reduced Th1 and Th17 cytokines known to contribute to the development of EAE. Anatabine appears to significantly suppress STAT3 and p65 NFκB phosphorylation in the spleen and the brain of EAE mice. These two transcription factors regulate a large array of inflammatory genes including cytokines suggesting a mechanism by which anatabine antagonizes pro-inflammatory cytokine production. Additionally, we found that anatabine alleviated the infiltration of macrophages/microglia and astrogliosis and significantly prevented demyelination in the spinal cord of EAE mice. Altogether our data suggest that anatabine may be effective in the treatment of MS and should be piloted in clinical trials.

Anatabine ameliorates experimental autoimmune thyroiditis

Tobacco smoking favorably influences the course of Hashimoto thyroiditis, possibly through the antiinflammatory proprieties of nicotine. In this study we tested anatabine, another tobacco alkaloid, in a model of experimental autoimmune thyroiditis. Experimental autoimmune thyroiditis was induced by different doses of thyroglobulin, to produce a disease of low, moderate, or high severity, in 88 CBA/J female mice: 43 drank anatabine supplemented water and 45 regular water. Mice were bled after immunization and killed to assess thyroid histopathology, thyroglobulin antibodies, T(4), and thyroid RNA expression of 84 inflammatory genes. We also stimulated in vitro a macrophage cell line with interferon-γ or lipopolysaccharide plus or minus anatabine to quantitate inducible nitric oxide synthase and cyclooxygenase 2 protein expression. Anatabine reduced the incidence and severity of thyroiditis in the moderate disease category: only 13 of 21 mice (62%) developed thyroid infiltrates when drinking anatabine as compared with 22 of 23 (96%) controls (relative risk 0.59, P = 0.0174). The median thyroiditis severity was 0.5 and 2.0 in anatabine and controls, respectively (P = 0.0007 by Wilcoxon rank sum test). Anatabine also reduced the antibody response to thyroglobulin on d 14 (P = 0.029) and d 21 (P = 0.045) after immunization and improved the recovery of thyroid function on d 21 (P = 0.049). In the thyroid transcriptome, anatabine restored expression of IL-18 and IL-1 receptor type 2 to preimmunization levels. Finally, anatabine suppressed in a dose-dependent manner macrophage production of inducible nitric oxide synthase and cyclooxygenase 2. Anatabine ameliorates disease in a model of autoimmune thyroiditis, making the delineation of its mechanisms of action and potential clinical utility worthwhile.

Thick collagen-based 3D matrices including growth factors to induce neurite outgrowth

Designing synthetic microenvironments for cellular investigations is a very active area of research at the crossroads of cell biology and materials science. The present work describes the design and functionalization of a three-dimensional (3D) culture support dedicated to the study of neurite outgrowth from neural cells. It is based on a dense self-assembled collagen matrix stabilized by 100-nm-wide interconnected native fibrils without chemical crosslinking. The matrices were made suitable for cell manipulation and direct observation in confocal microscopy by anchoring them to traditional glass supports with a calibrated thickness of ∼50μm. The matrix composition can be readily adapted to specific neural cell types, notably by incorporating appropriate neurotrophic growth factors. Both PC-12 and SH-SY5Y lines respond to growth factors (nerve growth factor and brain-derived neurotrophic factor, respectively) impregnated and slowly released from the support. Significant neurite outgrowth is reported for a large proportion of cells, up to 66% for PC12 and 49% for SH-SY5Y. It is also shown that both growth factors can be chemically conjugated (EDC/NHS) throughout the matrix and yield similar proportions of cells with longer neurites (61% and 52%, respectively). Finally, neurite outgrowth was observed over several tens of microns within the 3D matrix, with both diffusing and immobilized growth factors.

Nuclear factor-κB regulates βAPP and β- and γ-secretases differently at physiological and supraphysiological Aβ concentrations

Anatomical lesions in Alzheimer disease-affected brains mainly consist of senile plaques, inflammation stigmata, and oxidative stress. The nuclear factor-κB (NF-κB) is a stress-activated transcription factor that is activated around senile plaques. We have assessed whether NF-κB could be differentially regulated at physiological or supraphysiological levels of amyloid β (Aβ) peptides. Under these experimental conditions, we delineated the putative NF-κB-dependent modulation of all cellular participants in Aβ production, namely its precursor βAPP (β-amyloid precursor protein) and the β- and γ-secretases, the two enzymatic machines involved in Aβ genesis. Under physiological conditions, NF-κB lowers the transcriptional activity of the promoters of βAPP, β-secretase (β-site APP-cleaving enzyme 1, BACE1), and of the four protein components (Aph-1, Pen-2, nicastrin, presenilin-1, or presenilin-2) of the γ-secretase in HEK293 cells. This was accompanied by a reduction of both protein levels and enzymatic activities, thereby ultimately yielding lower amounts of Aβ and AICD (APP intracellular domain). In stably transfected Swedish βAPP-expressing HEK293 cells triggering supraphysiological concentrations of Aβ peptides, NF-κB activates the transcription of βAPP, BACE1, and some of the γ-secretase members and increases protein expression and enzymatic activities, resulting in enhanced Aβ production. Our pharmacological approach using distinct NF-κB kinase modulators indicates that both NF-κB canonical and alternative pathways are involved in the control of Aβ production. Overall, our data demonstrate that under physiological conditions, NF-κB triggers a repressive effect on Aβ production that contributes to maintaining its homeostasis, while NF-κB participates in a degenerative cycle where Aβ would feed its own production under pathological conditions.