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

Cocktail of three isoquinoline alkaloids derived from Glaucium grandiflorum Boiss. & A. Huet subsp. refractum (Nábelek) Mory inhibits the production of LPS-induced ROS, pro-inflammatory cytokines, and mediators through the down-regulation of p38 MAPK in BV-2 cells

Glaucium grandiflorum extracts have traditionally been used to treat brain-related disorders. G. grandiflorum extracts also exhibited inhibitory effects on cholinesterase enzymes, as well as antigenotoxic activity. However, no research has been done on the effect of G. grandiflorum alkaloid extracts on the anti-oxidative and anti-inflammatory mechanisms. In this study we aimed to evaluate the anti-oxidative and anti-inflammatory activities of the alkaloid extract obtained from G. grandiflorum as well as the mechanisms responsible for their neuroprotective effects in neuronal damage caused by LPS in BV2 cells. We used LC-MS/MS and 1H, 13C NMR analysis to determine the presence of major alkaloids (allocryptopine, tetrahydropalmatine, and tetrahydroberberine N-oxide (trans-cannadine-N-oxide) in the alkaloid extracts. We used flow cytometry to study the alkaloid extracts' effects on ROS production; we also employed qRT-PCR and Western Blot to analyze the effects of oxidative stress and inflammation-related genes and proteins. ROS production within the cell was inhibited by chloroform alkaloid extract (CAE). There occurred marked CAE-induced reductions in IL-1β, Cox-2, and iNOS mRNA expressions. We also observed marked reductions in IL-6 and TNF-α mRNA expressions with methanol alkaloid extract (MAE). CAE effectively suppressed IL-1β and iNOS protein levels, especially as in qRT-PCR studies, while MAE effectively reduced IL-6 and TNF-α protein levels. Additionally, MAE was found to be prominent in suppressing the levels of Cox-2 protein, unlike qRT-PCR studies. According to our study findings, oxidative stress brought about by inflammation was suppressed by alkaloid extracts from G. grandiflorum which can be attributed to their suppressor effects on the pro-inflammatory cytokines-mediators, and p38 MAPK. As a result, a drug active substance that suppresses oxidative stress and inflammation has been brought to the neuropharmacological field.

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.

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.