Protopine ameliorates OVA-induced asthma through modulatingTLR4/MyD88/NF-κB pathway and NLRP3 inflammasome-mediated pyroptosis.

BACKGROUND: Chronic airway inflammation and hyperresponsiveness are characteristics of asthma. The isoquinoline alkaloid protopine (PRO) has been shown to exert anti-inflammatory effects, but its mechanism of action in asthma is not known. PURPOSE: Investigate the protective properties of PRO upon asthma and elucidate its mechanism. STUDY DESIGN AND METHODS: The effects of PRO in asthma treatment were assessed by histology, biochemical analysis, and real-time reverse transcription-quantitative polymerase chain reaction. Then, we integrated molecular docking, western blotting, cellular experiments, immunohistochemistry, immunofluorescence analysis, flow cytometry, and metabolomics analysis to reveal its mechanism. RESULTS: In vivo, PRO therapy reduced the number of inflammatory cells (eosinophils, leukocytes, monocytes) in bronchoalveolar lavage fluid (BALF), ameliorated pathologic alterations in lung tissues, and inhibited secretion of IgG and histamine. Molecular docking showed that PRO could dock with the proteins of TLR4, MyD88, TRAF6, TAK1, IKKα, and TNF-α. Western blotting displayed that PRO inhibited the TLR4/NF-κB signaling pathway. PRO regulated expression of the pyroptosis-related proteins NLR family pyrin domain containing 3 (NLRP3) inflammasome, gasdermin D, caspase-1, and drove caspase-1 inactivation to affect inflammatory responses by inhibiting the NLRP3 inflammasome. In vitro, 24 h after treatment with PRO, cell activity, as well as levels of reactive oxygen species (ROS) and interleukin (IL)-1ß and IL-18, decreased significantly. Immunofluorescence staining showed that PRO decreased expression of TLR4 and MyD88 in vitro. PRO decreased nuclear translocation of NF-κB p65. Twenty-one potential biomarkers in serum were identified using metabolomics analysis, and they predominantly controlled the metabolism of phenylalanine, tryptophan, glucose, and sphingolipids. CONCLUSION: PRO reduced OVA-induced asthma. The underlying mechanism was associated with the TLR4/MyD88/NF-κB pathway and NLRP3 inflammasome-mediated pyroptosis.

Cattle Bile Arisaema Aqueous Extracts Protect Against Febrile Seizures in Rats Through Regulating Neurotransmitters and Suppressing Neuroinflammation.

Cattle bile Arisaema (CBA) is a traditional medicine used for the treatment of febrile seizures (FS) for thousands of years in China. However, its application is greatly limited due to cost reasons, and pig bile Arisaema (PBA) is the main commercial product instead. Additionally, the underlying mechanism of CBA for the treatment of FS still remains unknown. In this study, we investigated the anti-convulsant effect and potential mechanism of the CBA aqueous extract for the first time through a hot-water bath-induced FS rat model. Our results showed that pre-treatment with CBA dramatically lowered the incidence rate and generation times and prolonged the latency of FS. In addition, CBA effectively ameliorated neuronal damage and regulated neurotransmitter disorder induced by FS in the rat hippocampus. The enzyme-linked immunosorbent assay, western blotting, immunohistochemical, and qRT-PCR results exhibited that CBA suppressed the expression of GFAP, TLR4, NF-κB, HMGB1, NLRP3, TNF-α, IL-1ß, and IL-6 and consequently inhibited the neuroinflammation induced by FS. Interestingly, although the CBA and PBA aqueous extracts possessed the same trend on the changes caused by FS, the improvement of FS by CBA is markedly better than that by PBA. These findings indicate that CBA exerts a protective effect on febrile seizures through regulating neurotransmitter disorder and suppressing neuroinflammation.

A comprehensive review of research progress on the genus Arisaema: Botany, uses, phytochemistry, pharmacology, toxicity and pharmacokinetics.

ETHNOPHARMACOLOGICAL RELEVANCE: The genus Arisaema belongs to the family Araceae, which includes Chinese herbal medicines with wide-ranging pharmacological functions, including those useful for the treatment of stubborn phlegm, cough, epilepsy, tetanus, snakebite, rheumatoid arthritis, and other ailments. AIM OF THE STUDY: The current study aimed to comprehensively review the botany, uses, phytochemistry, pharmacology, toxicity, quality control and pharmacokinetics of plants in the genus Arisaema and to provide novel insights to develop future research in this field. MATERIALS AND METHODS: Relevant information on the genus Arisaema was obtained from published scientific materials (including materials from PubMed, Elsevier, Web of Science, Google Scholar, Baidu Scholar, CNKI, and Wiley) and other literature sources (e.g., the Chinese Pharmacopoeia, 2020 edition; Chinese herbal books and PhD and MSc thesis). RESULTS: The application information complied with this review and included processing techniques, traditional uses, clinical applications and classic prescriptions. Approximately 260 compounds, including flavonoids, alkaloids, saccharides, steroids, fatty acids, amino acids and volatile oils, have been separated and identified from the genus Arisaema. The isolated compounds exhibit wide-ranging pharmacological activities such as antitumor activity, analgesic and sedative activity, antioxidant activity and anti-inflammatory activity. The toxicity and irritant impacts, quality control, and pharmacokinetics are also discussed in this review. CONCLUSIONS: Plants in the genus Arisaema are valuable resources with therapeutic potential for a broad spectrum of ailments. Based on the limited literature, this review comprehensively and systematically summarizes current knowledge regarding the genus Arisaema for the first time. However, there have been insufficient studies on the active ingredients and germplasm and insufficient in-depth mechanistic studies. Therefore, isolation and identification of additional effective components and through research on the germplasm, pharmacodynamic mechanisms, and toxicology should be conducted to assess effectiveness and safety and to ensure the quality of the related drugs.