Aegeline, a natural product from the plant Aegle marmelos, mimics the yeast SNARE protein Sec22p in suppressing α-synuclein and Bax toxicity in yeast

Aegeline attenuates TNBS-induced colitis by suppressing the NFƙB-mediated NLRP3 inflammasome pathway in mice

A chronic inflammatory condition of the intestine, ulcerative colitis (UC), is challenging to successfully manage once diagnosed. Currently, available medical therapies for UC exhibit minimal efficacy with unacceptable side effects, while inventive biological agents are expensive and yet not well accepted by patients. Discovering more effective and safer treatments to treat UC is therefore essential. One of the primary alkaloids found in Aegle marmelos, aegeline, has anti-inflammatory and antioxidant properties as well as being able to suppress several pro-inflammatory cytokines responsible for inflammation. The study aimed to investigate the effectiveness of aegeline in alleviating 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis through the NFƙB-mediated NLRP3 inflammasome pathway. Mice were randomly allocated into six groups, Normal control (NC), Model control (MC-TNBS, 2,4,6-trinitrobenzene sulfonic acid), STD (TNBS + sulfasalazine 100 mg/kg), AG1, AG2, and AG3 (TNBS + aegeline 5, 10, 20 mg/kg) respectively. Physical parameters such as a change in body weight, stool consistency, rectal bleeding, colon length, myeloperoxidase (MPO) levels and nitric oxide (NO) levels, and disease activity index (DAI) were assessed and supporting gene expression studies of various pro-inflammatory cytokines and enzymes were evaluated and histopathological changes observed. Administration of aegeline (10, 20 mg/kg) was found to be effective in colon protection by lowering the disease activity score and myeloperoxidase level and improving other physical parameters. Aegeline in high dose significantly downregulated the gene expression of NFƙB, iNOS, COX-2, NLRP3, IL-1β, and IL-18, conferring great anti-inflammatory potential. Suggestive of the findings, aegeline reduced the damage to the colon by downregulating transcriptional genes and enzymes leading to inflammation and mitigated TNBS-induced colitis probably through the NFƙB-mediated NLRP3 inflammasome pathway.

Metabolic Activation of Aegeline Mediated by CYP2C19

1. Aegeline (AGL) is a natural alkaloidal amide mainly isolated from the leaves and fruits of tropical plant Aegle marmelos, with multiple pharmacological activities.2. As one component of several dietary supplements, AGL caused a series of acute and chronic liver injuries. Nevertheless, the mechanisms of AGL-induced hepatotoxicity remain unclear. This study was conducted to identify reactive metabolite(s), to determine related metabolic pathways, and define the possible association of the bioactivation with AGL cytotoxicity.3. A demethylation metabolite (M1) and a GSH conjugate (M2) were detected in rat liver microsomal incubations containing AGL and GSH. The two metabolites were both found in bile of rats and rat primary hepatocytes after AGL administration.4. Recombinant P450 enzyme incubations showed that CYP2C19 was the principal enzyme catalyzing this metabolic activation.5. Ticlopidine, a selective inhibitor of CYP2C19, decreased the formation of M1 and M2 in hepatocytes and attenuated the susceptibility of hepatocytes to the cytotoxicity of AGL. The results suggest that AGL was metabolized to a p-quinone methide intermediate which could in part participate in AGL-induced cytotoxicity.

Biological Evaluation of Aegle marmelos Fruit Extract and Isolated Aegeline in Alleviating PainDepression Dyad: In Silico Analysis of Aegeline on MAO-A and iNOS

Pain and depression have been assessed to co-occur in up to 80% of patients, and this comorbidity is more debilitating and pricier for the patients as compared to either of these disorders alone. Aegle marmelos is a well-known medicinal plant with a broad spectrum of pharmacological activities. Aegeline is a relatively unexplored molecule present in Aegle marmelos. Therefore, the current investigation aims to explore the potential of Aegle marmelos fruit extract (AMFE) and isolated aegeline against the reserpine-induced pain-depression dyad. In the current investigation, aegeline was isolated from AMFE, followed by spectroscopic characterization, i.e., using NMR and mass analyses. AMFE (200 mg kg^-1 p.o) and aegeline (10 mg kg^-1 p.o.) were administered to reserpinized (0.5 mg kg^-1 s.c.) mice, and clorgyline (3 mg kg^-1 i.p.) was taken as the standard drug. AMFE and aegeline significantly alleviated the reserpine-induced reduction in a pain threshold and an increase in immobility as observed in behavioral tests of pain and depression, respectively. In silico molecular docking studies of aegeline showed a good binding interaction at the active sites of MAO-A and iNOS. The in vivo analysis showed that AMFE and aegeline treatment significantly decreased the monoamine oxidase-A (MAO-A) activity, serum interleukin-6 (IL-6) level, and lipid peroxidation, along with an increase in the reduced glutathione level in comparison to the reserpine-treated group. Immunofluorescence studies also showed that AMFE and aegeline abrogated the reserpine-induced increase in iNOS expression. Conclusively, the results delineate that AMFE and aegeline might exert a protective effect via downregulating the MAO-A hyperactivity, IL-6 level, oxidative and nitrosative stress.

Impact of Natural Compounds on Neurodegenerative Disorders: From Preclinical to Pharmacotherapeutics

Among the major neurodegenerative disorders (NDDs), Alzheimer’s disease (AD) and Parkinson’s disease (PD), are a huge socioeconomic burden. Over many centuries, people have sought a cure for NDDs from the natural herbals. Many medicinal plants and their secondary metabolites are reported with the ability to alleviate the symptoms of NDDs. The major mechanisms identified, through which phytochemicals exert their neuroprotective effects and potential maintenance of neurological health in ageing, include antioxidant, anti-inflammatory, antithrombotic, antiapoptotic, acetylcholinesterase and monoamine oxidase inhibition and neurotrophic activities. This article reviews the mechanisms of action of some of the major herbal products with potential in the treatment of NDDs according to their molecular targets, as well as their regional sources (Asia, America and Africa). A number of studies demonstrated the beneficial properties of plant extracts or their bioactive compounds against NDDs. Herbal products may potentially offer new treatment options for patients with NDDs, which is a cheaper and culturally suitable alternative to conventional therapies for millions of people in the world with age-related NDDs.