Sanguinarine-Chelerythrine Fraction of Coptis chinensis Exerts Anti-inflammatory Activity in Carrageenan Paw Oedema Test in Rats and Reveals Reduced Gastrotoxicity

Antibacterial Effect and Mechanism of Chelerythrine on Xanthomonas oryzae pv. oryzae

Xanthomonas oryzae pv. oryzae (Xoo) is a biotrophic bacterial pathogen, which causes devastating bacterial blight disease worldwide. In this study, we thoroughly investigated the antimicrobial effect of the plant-derived extract chelerythrine against Xanthomonas oryzae pv. oryzae (Xoo) and elucidated its mechanism. Chelerythrine is a quaternary ammonium alkaloid with a 2,3,7,8-tetrasubstituted phenanthridine structure, extracted from plants, such as the whole plant of Chelidonium majus, and the roots, stems, and leaves of Macleaya cordata. We found that chelerythrine significantly inhibited the growth of Xoo at a concentration of 1.25 μg/mL. Further experiments revealed that chelerythrine interfered with the division and reproduction of the bacterium, leading to its filamentous growth. Additionally, it increased the permeability of Xoo cell membranes and effectively decreased the pathogenicity of Xoo, including the inhibition of extracellular polysaccharide production, cellulase secretion, and biofilm formation. Chelerythrine induced the accumulation of reactive oxygen species in the bacterium, triggering oxidative stress. The result showed that chelerythrine inhibited the formation of the Z-ring of Xoo, interfered with the synthesis of pyrimidine and purine nucleotides, inhibited DNA damage repair, and inhibited the formation of peptidoglycan and lipid-like A, thus interfering with cell membrane permeability, inhibiting carbohydrate metabolism and phosphorylation of sugars, reducing pathogenicity, and ultimately inhibiting bacterial growth and leading to the destruction or lysis of bacterial cells. Altogether, our results suggest that the antimicrobial effect of chelerythrine on Xoo exhibits multi-target properties. Additionally, its effective inhibitory concentration is low. These findings provide a crucial theoretical basis and guidance for the development of novel and efficient plant-derived antimicrobial compounds.

Sanguinarine-Chelerythrine from Coptis chinensis Offers Analgesic and Anti-Inflammatory Effects Without Gastrotoxicity

Background: Pain is a major clinical and socioeconomic problem worldwide. The available therapies are not always effective and are often associated with the multiple adverse effects that reduce their clinical application. Natural compounds are an important group of pharmaceuticals that may be used in pain management. We aimed to investigate the analgesic activity of the sanguinarine-chelerythrine from Coptis chinensis. Methods: The analgesic and anti-inflammatory activity of the sanguinarine-chelerythrine fraction of C. chinensis extract (SC 5 and 10 mg/kg), sanguinarine (SAN 1 and 2 mg/kg) and chelerythrine (CHEL 4 and 8 mg/kg) was assessed in tail flick and formalin tests. A microscopic and macroscopic examination of stomach mucosae was performed. TNFα and MMP-9 levels were measured with ELISA kits. Results: Morphine (MORF), CHEL and SC prolongated the tail withdrawal latency, with comparable analgesic activity between MORF and CHEL 8 mg/kg. MORF, CHEL 8 mg/kg, and SAN 2 mg/kg ameliorated the pain reaction in the neurogenic phase of the formalin test. In the inflammatory phase of the formalin test, all tested substances exerted analgesic activity. SAN, CHEL and SC additionally reduced TNFα and MMP-9 secretion. Conclusions: Our results confirmed analgesic effects of CHEL and SC with CHEL analgesic activity comparable to MORF. All investigated substances exerted significant anti-inflammatory activity without concomitant gastrotoxicity.

Exploration of anti-inflammatory activity of pyrazolo[3,4-d]pyrimidine/1,2,4-oxadiazole hybrids as COX-2, 5-LOX and NO release inhibitors: Design, synthesis, in silico and in vivo studies

New pyrazolo[3,4-d]pyrimidine derivatives 7a-h and 8a-h were synthesized and evaluated for their in vitro inhibitory potential against COX-1, COX-2, 5-LOX along with the NO release inhibitory activity to assess their anti-inflammatory potential. Most compounds confered inhibitory activity at a micromolar level and exhibited prominent selectivity towards COX-2 especially in the 8a-h series. The most useful compound 8e as a COX-2/5-LOX dual inhibitor, exhibited IC50 results of; 1.837 µM for COX-2, 2.662 µM for 5-LOX with an acceptable NO release inhibition rate of 66.02 %. Compounds 7e, 7f, 8e and 8f proved their efficiency as 5-LOX/NO release dual inhibitors; with IC50 values of 2.833, 1.952, 2.662 and 1.573 µM, respectively for 5-LOX biotarget, and with superior NO inhibitory ratio of 73.85, 65.57, 66.02 and 72.28 %, respectively. The in vivo anti-inflammatory assay explored that 7e is the most effective with minimal gastric ulceration prevalence. Molecular docking in the active site of both COX-2 and 5-LOX showed that, the most active 8e and 7e are correctly oriented inside the COX-2 binding pocket with unique binding mode independently on the reference celecoxib. Also, they demonstrated superior binding affinities to the 5-LOX enzyme over both the Zileuton as a reference drug and the normal ligand 30Z. The stability of the complex formed between the most promising candidates 7e or 8e with the COX-2 and 5-LOX active sites, was considered using a typical atomistic 100 ns dynamic simulation study. Investigation of the SAR revealed the importance of both the sulfonamide group in the 8a-h series and the substituents of the 3-phenyl ring tethered on the 1,2,4-oxadiazole core.

Ethoxychelerythrine as a potential therapeutic strategy targets PI3K/AKT/mTOR induced mitochondrial apoptosis in the treatment of colorectal cancer

Several alkaloids found in the Zanthoxylum genus have demonstrated significant anticancer activity. However, the antitumor effects of Ethoxychelerythrine (Eth) have not been previously reported. Cell viability, colony formation, apoptosis and cell cycle analysis, intracellular and reactive oxygen species (ROS), mitochondrial membrane potential (MMP) levels of Eth against SW480 cells were evaluated. Subcutaneously transplanted SW480 cells model was used to determine the effect of Eth on tumor growth in vivo. Inflammation levels, angiogenic factors, pathological observations, quantitative reverse-transcription PCR (qRT-PCR), quantitative proteomics, metabolite profiles and western blotting were conducted. It found that Eth significantly inhibited the proliferation of SW480 and HT29 cells in vitro, with stronger inhibitory activity observed against SW480 cells. Therefore, subsequent studies focused on SW480 cells. In vitro, we observed that Eth arrested the cell cycle at the G0/G1 phase, decreased MMP levels, elevated cellular ROS levels, and induced mitochondrial apoptosis. In vitro, Eth significantly inhibited tumor proliferation and metastasis, and regulated the molecule levels of angiogenesis and inflammatory factors in serum, as well as apoptotic protein in tumor tissues. The serum proteomic revealed that the differential proteins were primarily involved in the PI3K/AKT/mTOR pathway, including laminin β1 (Lamb1), and type I collagen (Col1a1). Metabolomics showed that many abnormal levels of metabolites regulated by the PI3K/AKT/mTOR pathway were obviously reversed towards normal levels after Eth intervention. The correlation analysis between the two-omics revealed that different proteins in the PI3K/AKT pathway, particularly lactate dehydrogenase B (LDHB) and glutathione synthetase (GSS), can interact with most of different metabolites. In summary, Eth exerts anti-tumour effects by inhibiting the activation of the PI3K/AKT/mTOR pathway, which in turn activates mitochondrial apoptosis. Eth may be considered in the development of drugs for relieving colon cancer patients in the future.

Antileishmanial, antitrypanosomal and anti-coronavirus activities of benzophenanthridine alkaloids and other specialized metabolites isolated from the root bark of Zanthoxylum zanthoxyloides (Lam.) B.Zepernick & Timler

Strong antileishmanial and antitrypanosomal activities were highlighted for the crude methanolic extract (IC50 = 0.61 and 2.15 μg/mL, respectively) of Zanthoxylum zanthoxyloides (Lam.) B.Zepernick & Timler root bark, as well as for its apolar partitions (cyclohexane: IC50 = 0.66 and 5.17 μg/mL, respectively and dichloromethane: IC50 = 0.07 and 0.22 μg/mL, respectively), with a good selectivity index (SI) towards WI-38 cells. In addition, cyclohexane and dichloromethane extracts exhibited a dose-dependent inhibition of human coronavirus HCoV-229E infection in hepatoma Huh-7 cells expressing or not the cellular protease TMPRSS2 (IC50 values of 5.29 μg/mL and 4.87 μg/mL, respectively). Fractionation of these active extracts led to the isolation of a new racemic benzophenanthridine alkaloid named zanthoxyloithrine (1), together with 13 known compounds. Their structures were elucidated by spectroscopic techniques including IR, UV, HR-MS, 1D and 2D NMR and electronic circular dichroism. In parallel, HR-ESI-MS/MS based dereplication and molecular networking analysis were performed to identify unpurified compounds in cyclohexane and dichloromethane extracts. Zanthoxyloithrine (1) showed strong antileishmanial (IC50 = 0.14 μM, SI = 52.0) and antitrypanosomal (IC50 = 0.36 μM, SI = 20.8) activities. In addition, compound (1) demonstrated a high antiviral activity against HCoV-229E with IC50 value of 6.70 μM in presence of TMPRRS2 and without significant toxicity on Huh-7 cells. Other purified benzo[c]phenanthridine alkaloids also showed anti-coronavirus and antiparasitic activities.

Chelerythrine ameliorates Aspergillus fumigatus keratitis through suppressing the LOX-1/p38 MAPK signaling pathway

PURPOSE

Aspergillus fumigatus (A. fumigatus) keratitis is a type of infectious corneal disease that significantly impairs vision. The objective of this study is to evaluate the therapeutic potential of chelerythrine (CHE) on A. fumigatus keratitis.

METHODS

The antifungal activity of CHE was assessed through various tests including the minimum inhibitory concentration test, scanning electron microscopy, transmission electron microscopy, propidium iodide uptake test and plate count. Neutrophil infiltration and activity were assessed using immunofluorescence staining and the myeloperoxidase test. RT-PCR, western blotting assay, and ELISA were performed to measure the expression levels of proinflammatory cytokines (IL-1β and IL-6), NF-E2-related factor (Nrf2), heme oxygenase-1 (HO-1), and lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), as well as to determine the ratio of phosphorylated-p38 (p-p38) mitogen-activated protein kinase (MAPK) to p38 MAPK.

RESULTS

In vitro, CHE inhibited the growth of A. fumigatus conidia, reduced fungal hyphae survival, and prevented fungal biofilm formation. In vivo, CHE reduced the severity of A. fumigatus keratitis and exhibited an excellent anti-inflammatory effect by blocking neutrophil infiltration. Furthermore, CHE decreased the expression levels of proinflammatory cytokines and LOX-1 at both mRNA and protein levels, while also decreasing the p-p38 MAPK/p38 MAPK ratio. Additionally, CHE increased the expression levels of Nrf2 and HO-1.

CONCLUSION

CHE provides protection against A. fumigatus keratitis through multiple mechanisms, including reducing fungal survival, inducing anti-inflammatory effects, enhancing Nrf2 and HO-1 expression, and suppressing the signaling pathway of LOX-1/p38 MAPK.

Recent Advances in Alkaloids from Papaveraceae in China: Structural Characteristics and Pharmacological Effects

The Papaveraceae plant family serves as a botanical reservoir for a variety of medicinal compounds that have been traditionally utilized in Chinese medicine for numerous generations. Growing attention towards the pharmaceutical potential of Papaveraceae has resulted in the identification of many alkaloids, which have attracted significant attention from the scientific community because of their structural complexity and wide range of biological activities, such as analgesic, antihypertensive, antiarrhythmic, anti-inflammatory, antibacterial, anti-tumor, anti-cancer, and other activities, making them potential candidates for medical use. The primary objective of this review is to analyze the existing literature on the historical use of Papaveraceae plants, focusing on their alkaloid structures and relationship with pharmacological effects, as well as provide a theoretical basis for their clinical application, with the goal of unveiling the future potential of Papaveraceae plants.

Identification of Sanguinarine Metabolites in Rats Using UPLC-Q-TOF-MS/MS

Sanguinarine (SAN), as the main active component of a traditional Chinese veterinary medicine, has been widely used in the animal husbandry and breeding industry. However, the metabolites of SA are still uncertain. Therefore, this research aimed to investigate the metabolites of SA based on rats in vivo. The blood, feces, and urine of rats were collected after the oral administration of 40 mg/kg SAN. Ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS) was employed to identify the metabolites of SAN. The elemental composition of sanguinarine metabolites was inferred by analyzing their exact molecular weight, and the structures of the metabolites were predicted based on their fragment ions and cleavage pathways. A total of 12 metabolites were identified, including three metabolites in the plasma, four in the urine, and nine in the feces. According to the possible metabolic pathways deduced in this study, SAN was mainly metabolized through reduction, oxidation, demethylation, hydroxylation, and glucuronidation. This present research has summarized the metabolism of SAN in rats, which is helpful for further studying the metabolic mechanism of SAN in vivo and in vitro.

Developmental toxicity induced by chelerythrine in zebrafish embryos via activating oxidative stress and apoptosis pathways

Chelerythrine (CHE), a natural benzophenanthridine alkaloid, possesses various biological and pharmacological activities, such as antimicrobial, antitumor and anti-inflammatory effects. However, its adverse side effect has not been fully elucidated. Therefore, this study was designed to investigate the developmental toxicity of CHE in zebrafish. We found that CHE could lead to a notably increase of the mortality and malformation rate, while lead to reduction of the hatching rate and body length. CHE also could affect the normal developing processes of the heart, liver and phagocytes in zebrafish. Furthermore, the reactive oxygen species (ROS) and apoptosis levels were notably increased. In addition, the mRNA expressions of genes (bax, caspase-9, p53, SOD1, KEAP1, TNF-α, STAT3 and NF-κB) were significantly increased, while the bcl2 and nrf2 were notably inhibited by CHE. These results indicated that the elevation of ROS and apoptosis were involved in the developmental toxicity induced by CHE. In conclusion, CHE exhibits a developmental toxicity in zebrafish, which helps to understand the potential toxic effect of CHE.

Protopine Alleviates Dextran Sodium Sulfate-Induced Ulcerative Colitis by Improving Intestinal Barrier Function and Regulating Intestinal Microbiota

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD), and its pathogenesis is related to intestinal mucosal barrier damage and gut microbiota imbalance. Protopine (PRO), an isoquinoline alkaloid, is one of the main anti-inflammatory ingredients of traditional Chinese medicine Macleaya cordata(Willd.) R. Br. This study investigated the effects of PRO on the intestinal mucosal barrier and gut microbiota in dextran sodium sulfate (DSS)-induced colitis mice. C57BL/6J mice were treated with 3% DSS in drinking water to induce acute colitis, while PRO was administered orally once daily for 7 days. The results showed that PRO administration significantly alleviated the symptoms of DSS-induced colitis in mice and inhibited the expression of inflammation-related genes. In addition, PRO restored the integrity of the intestinal barrier in colitis mice by restoring colonic mucin secretion and promoting the expression of tight junction proteins. Furthermore, PRO alleviated the DSS-induced gut microbiota dysbiosis by decreasing the abundance of Proteobacteria, Escherichia-Shigella and Enterococcus, as well as enhancing the abundance of beneficial bacteria, such as Firmicutes and Akkermansia. These findings suggested that PRO effectively alleviated DSS-induced ulcerative colitis by suppressing the expression of inflammation-related genes, maintaining the intestinal mucosal barrier and regulating the intestinal microbiota.

Gut fungi differentially response to the antipyretic (heat-clearing) and diaphoretic (exterior-releasing) traditional Chinese medicines in Coptis chinensis-conditioned gut microbiota

Antipyretic (heat-clearing) and diaphoretic (exterior-releasing) drugs are two main groups of traditional Chinese medicines (TCMs) possessing anti-microbes and anti-inflammation effects, with the former mainly through clearing pyrogens while the latter through promoting diaphoresis. Although anti-microorganism is a common action of these two kinds of TCMs, their difference in antimicrobial spectrums and their interactions when combinedly used remain unclear. Herein, we prepared aqueous extracts from Coptis chinensis (HL) and other antipyretic or diaphoretic TCMs, orally administrated them to C57BL/6 mice at a clinical dose for fourteen days, and analyzed their impaction on both gut bacteria and fungi using full-length 16 S rRNA gene sequencing and internal transcribed spacer 1/2 (ITS1/2) gene sequencing, respectively. Oral administration of HL significantly changed the structure of gut bacteria but showed little influence on gut fungi. Co-treatment with antipyretic or diaphoretic TCMs alleviated the impact of HL on gut bacteria to a similar degree. However, combined with either heat-clearing or exterior-releasing TCMs significantly strengthened the influence of HL on gut fungi, with the latter superior to the former. The antipyretic TCMs enriched Penicillium spp. while diaphoretic TCMs promoted Fusarium spp. Further analysis revealed that the diaphoretic TCMs-enriched fungi Fusarium spp. were positively related to Akkermansia spp., a beneficial bacterium that interacts with Toll-like receptor 4 (TLR4) and regulates thermogenesis, thus providing a potential linkage with their pro-diaphoresis effect. Together, our results reveal that gut fungi differentially respond to the impact of heat-clearing and exterior-releasing TCMs on Coptis chinensis-conditioned gut microbiota, which provides insights into their functional characteristics.

Preclinical safety evaluation of Macleaya Cordata extract: A re-assessment of general toxicity and genotoxicity properties in rodents

Macleaya cordata extract (MCE) is widely used for its diverse pharmacological actions and beneficial effects on farm animals. Modern pharmacological studies have shown that it has anti-inflammatory, anti-cancer, and anti-bacterial activities, and is gradually becoming a long-term additive veterinary drug used to improve animal intestinal health and growth performance. Although some evidence points to the DNA mutagenic potential of sanguinarine (SAN), a major component of MCE, there is a lack of sufficient basic toxicological information on the oral route, posing a potential safety risk for human consumption of food of animal origin. In this study, we assessed the acute oral toxicity, repeated 90-day oral toxicity and 180-day chronic toxicity of MCE in rats and mice and re-evaluated the genotoxicity of MCE using a standard combined in vivo and ex vivo assay. In the oral acute toxicity test, the LD₅₀ for MCE in rats and mice was 1,564.55 mg/kg (95% confidence interval 1,386.97–1,764.95 mg/kg) and 1,024.33 mg/kg (95% confidence interval 964.27–1,087.30 mg/kg), respectively. The dose range tested had no significant effect on hematology, clinical chemistry, and histopathological findings in rodents in the long-term toxicity assessment. The results of the bacterial reverse mutation, sperm abnormality and micronucleus test showed negative results and lack of mutagenicity and teratogenicity; the results of the rat teratogenicity test showed no significant reproductive or embryotoxicity. The results indicate that MCE was safe in the dose range tested in this preclinical safety assessment. This study provides data to support the further development of maximum residue limits (MRLs) for MCE.

Exploring the Anti-inflammatory Effects of Protopine Total Alkaloids of Macleaya Cordata (Willd.) R. Br

Macleaya cordata (Willd). R. Br. is a Chinese medicinal plant commonly used externally to treat inflammatory-related diseases such as arthritis, sores, and carbuncles. This study aimed to evaluate the anti-inflammatory activity of protopine total alkaloids (MPTAs) in Macleaya cordata (Willd.) R. Br. in vivo tests in rats with acute inflammation showed that MPTA (2.54 and 5.08 mg/kg) showed significant anti-inflammatory activity 6 h after carrageenan injection. Similarly, MPTA (3.67 and 7.33 mg/kg) showed significant anti-inflammatory activity in the mouse ear swelling test. In addition, the potential mechanisms of the anti-inflammatory effects of MPTA were explored based on network pharmacology and molecular docking. The two main active components of MPTA, protopine and allocryptopine, were identified, and the potential targets and signaling pathways of MPTA's anti-inflammatory effects were initially revealed using tools and databases (such as SwissTargetPrediction, GeneCards, and STRING) combined with molecular docking results. This study provides the basis for the application of MPTA as an anti-inflammatory agent.