Systematic review of the alkaloid constituents in several important medicinal plants of the Genus Corydalis

Corydecusines A-H, new phthalideisoquinoline hemicetal alkaloids from the bulbs of Corydalis decumbens inhibit Tau pathology by activating autophagy mediated by AMPK-ULK1 pathway

Twelve phthalideisoquinoline hemiacetal alkaloids including eight new ones (1-8) and one natural alkaloid characterized by an aziridine moiety with unassigned NMR data (9), were isolated and identified from the bulbs of Corydalis decumbens. Their structures were established by comprehensive analyses of HRESIMS, NMR, X-ray crystallography, and ECD analyses. The unambiguously established structures of the phthalideisoquinoline hemiacetal alkaloids indicated that the absolute configurations of C-1, C-9, and C-7' were confusable only relied on coupling constants. A summary of their ECD spectra was concluded and provided an insight for C-1, C-9, and C-7' absolute configuration assignment. These new compounds were evaluated to induce autophagy flux through flow cytometry analysis. Moreover, compounds 2 and 6 could significantly induce autophagy and inhibit Tau pathology by AMPK-ULK1 pathway activation, which provided an avenue for anti-AD lead compounds discovery.

Benzylisoquinoline alkaloids with their antitumor activity from the aerial parts of Corydalis impatiens (pall.) Fisch

Phytochemical investigation on the aerial parts of Corydalis impatiens (pall.) Fisch (Papaveraceae) resulted in the identification of four previous undescribed benzylisoquinoline alkaloids, impatienines A-D (1-4), together with 14 known analogues (5-18). The structures of these compounds were elucidated by extensive spectroscopic analysis (IR, HR-ESIMS, 1D- and 2D-NMR) as well as ECD calculations. All the compounds obtained were investigated for their inhibitory effect on the growth of A549, H1299 and HepG2 cancer cells. Compounds 7 and 15 exhibited pronounced inhibition against the A549 cancer cells with IC50 values of 6.81 μM and 3.17 μM, while the positive control cisplatin was 1.83 μM. Compounds 1-3 showed moderate inhibitory on the H1299 cancer cells. Compounds 4, 10-12, and 16 showed signiffcant activity against HepG2 cancer cells with IC50 values range of 4.41-8.75 μM.

New trends in the practical use of isoquinoline alkaloids as potential drugs applicated in infectious and non-infectious diseases

In the last years, traditional natural products have been the center of attention for the scientific community and exploration of their therapeutic abilities is proceeding permanently. Isoquinoline alkaloids have always attracted scientific interest due to either their positive or negative effects on human organism. The present review describes research on isoquinoline alkaloids isolated from different plant species. Alkaloids are one of the most important classes of plant derived compounds among these isoquinoline alkaloids possess varied biological activities such as anticancer, antineurodegenerative diseases, antidiabetic, antiinflammatory, antimicrobial, and many others. The use of plants against different disorders is entrenched in traditional medicine around the globe. Recent progress in modern therapeutics has stimulated the use of natural products worldwide for various ailments and diseases. The review provides a collection of information on the capabilities of some isoquinoline alkaloids, its potential for the treatment of various diseases and is designed to be a guide for future research on different biologically active isoquinoline alkaloids and plant species containing them. The authors are aware that they were not able to cover the whole area of the topic related to biological activity of isoquinoline alkaloids. This review is intended to suggest directions for further research and can also help other researchers in future studies.

(±)-Yanhusuomide A, a pair of ornithine-fused benzylisoquinoline enantiomers from Corydalis yanhusuo

(±)-Yanhusuomide A (1), a novel enantiomeric pair of ornithine-fused benzylisoquinoline, were characterized from the dried tubers of Corydalis yanhusuo, along with a biogenetically related intermediate oblongine (2). Yanhusuomide A features an unprecedented skeleton based on a benzylisoquinoline coupled with an ornithine derivative to form a rare 5,6-dihydro-4H-pyrido[3,4,5-de]quinazoline motif. Plausible biosynthetic pathway of 1 was proposed, and (±)-yanhusuomide A (1) presented potential inhibitory bioactivity against acetylcholinesterase (AChE) with IC₅₀ = 14.07 ± 2.38 μM. The simulation of molecular docking displayed that 1 generated strong interaction with Asp-74 and Trp-86 residues of AChE through attractive charge of the quaternary nitrogen.

New alkaloids and their in vitro antitumor activity of Corydalis balansae

The chemical investigation on Corydalis balansae resulted in the isolation of three previous undescribed compounds (1, 10, and 11) and 17 known compounds. Compound 1 and 2 were obtained as two lignanamide dimers, and compound 11 had a spiro [benzofuranone-benzazepine] skeleton, which was found in Corydalis for the first time. The structures of new compound were determined by the detailed analysis of 1D/2D NMR, UV, and IR data. Absolute configurations of compounds 10 and 11 were defined by their crystal X-ray diffraction data and calculations of electronic circular dichroism (ECD). The CCK-8 method was used to assay the inhibition effect of all the compounds on the growth of Hela, MGC-803, A549, and HepG2 cancer cells. Compound 2, 13, and 14 showed moderate inhibitory activity against the tested cell lines. Compound 2 exhibited potential antitumor activity against MGC-803 cells with an IC50 value of 20.8 μM, while the positive control etoposide was 17.3 μM. Furthermore, results from the cellular-mechanism investigation indicated that compound 2 could induce S-phase cell-cycle arrest and MGC-803 cells apoptosis, which was triggered by the up-regulation of PARP1, caspase-3 and -9, Bax, and down-regulation of Bcl-2. The 2-induced strong apoptosis indicated that compound 2 had good potential as an antitumor lead compound.

Structures, biomimetic synthesis, and anti-SARS-CoV-2 activity of two pairs of enantiomeric phenylpropanoid-conjugated protoberberine alkaloids from the rhizomes of Corydalis decumbens

(±)-Decumicorine A (1) and (±)-epi-decumicorine A (2), two pairs of enantiomeric isoquinoline alkaloids featuring a novel phenylpropanoid-conjugated protoberberine skeleton, were isolated and purified from the rhizomes of Corydalis decumbens. The separation of (±)-1 and (±)-2 was achieved by chiral HPLC to produce four optically pure enantiomers. The structures and absolute configurations of compounds (−)-1, (+)-1, (−)-2, and (+)-2 were elucidated by spectroscopic analysis, ECD calculations, and X-ray crystallographic analyses. The two racemates were generated from a Diels-Alder [4 + 2] cycloaddition between jatrorrhizine and ferulic acid in the proposed biosynthetic pathways, which were fully verified by a biomimetic synthesis. Moreover, compound (+)-1 exhibited an antiviral entry effect on SARS-CoV-2 pseudovirus by blocking spike binding to the ACE2 receptor on HEK-293T-ACE2^h host cells.

A Web-Based Pharmacological Approach to the Mechanism of Action of Rhizoma Phragmitis and Rhizoma Curcumae in the Treatment of Chronic Atrophic Gastritis

Objective. To analyze and test the effect of Rhizoma phragmitis and Rhizoma curcumae on the network pharmacology of MAPK (mitogen-activated protein kinase) and TNF (tumor necrosis factor) signaling channels and inflammatory factor target gene regulation in successful modeling of chronic atrophic gastritis rats. Methods. Rats with chronic atrophic gastritis that were modeled successfully were randomly divided into control and study groups and were treated with conventional western medicine or Rhizoma phragmitis and Rhizoma curcumae, respectively. The pharmacological mechanism of action and efficacy were evaluated. Results. The treatment efficiency was 76.32% and 97.37% in the control and study group, respectively. After treatment, the serum tumor necrosis factor-α (TNF-α) and serum malondialdehyde (MDA) levels in the study group were lower than those in the control group and the serum epidermal growth factor (EGF) and superoxide dismutase (SOD) levels in the study group were higher than those in the control group (P < 0.05); the pain behavioral scores in the study group were lower than those in the control group, and the free acid quantity and total acid quantity in the study group were higher than those in the control group (P < 0.05); the serum MTL index in the study group was higher than that in the control group, and the serum gastrin (GAS) and pepsinogen I (PG I) indices in the study group were lower than those in the control group (P < 0.05); the number of 24-hour reflux in the study group was less than that in the control group (P < 0.05), and the longest reflux time in the study group was lower than that in the control group (P < 0.05). Conclusion. Based on the network pharmacological results, Rhizoma phragmitis and Rhizoma curcumae will modulate MAPK, TNF signaling circuits, and inflammatory factor target genes in the chronic atrophic gastritis rat model. This treatment protocol is efficient and beneficial to enhance the gastric function of the chronic atrophic gastritis rat model, while it can alleviate the inflammatory response and significantly reduce the number and duration of reflux, which is a safe and reliable treatment modality.

New Insights Into the Backbone Phylogeny and Character Evolution of Corydalis (Papaveraceae) Based on Plastome Data

A robust backbone phylogeny is fundamental for developing a stable classification and is instructive for further research. However, it was still not available for Corydalis DC., a species-rich (> 500 species), ecologically and medically important, but taxonomically notoriously difficult genus. Here, we constructed backbone phylogeny and estimated the divergence of Corydalis based on the plastome data from 39 Corydalis species (32 newly sequenced), which represent ca. 80% of sections and series across this genus. Our phylogenetic analyses recovered six fully supported main clades (I-VI) and provided full support for the majority of lineages within Corydalis. Section Archaeocapnos was unexpectedly turned out to be sister to the rest of the subg. Corydalis s. l. (clades IV-VI), thus treating as a distinct clade (clade III) to render all the main clades monophyletic. Additionally, some unusual plastome structural rearrangements were constantly detected within Corydalis and were proven to be lineage-specific in this study, which, in turn, provided further support to our phylogeny. A segment containing five genes (trnV-UAC-rbcL) in the plastome's LSC region was either normally located downstream of the ndhC gene in clade I species or translocated downstream of the atpH gene in clade II species or translocated to downstream of the trnK-UUU gene in clade III-VI species. The unique large inversion (ca. 50 kb) in the plastome LSC region of clade III species, representing an intermediate stage of the above translocation in clades IV-VI, firmly supported clade III as a distinct and early diverged clade within this large lineage (clades III-VI). Our phylogeny contradicted substantially with the morphology-based taxonomy, rejected the treatment of tuberous species as an independent evolutionary group, and proved that some commonly used diagnostic characters (e.g., root and rhizome) were results of convergent evolution, suggestive of unreliability in Corydalis. We dated the origin of crown Corydalis to the early Eocene (crown age 49.08 Ma) and revealed possible explosive radiation around 25 Ma, coinciding with the drastic uplift of the Qinghai-Tibetan Plateau in Oligocene and Miocene. This study provided the most reliable and robust backbone phylogeny of Corydalis to date and shed some new insights on the evolution of Corydalis.

Isoquinoline alkaloids from the Corydalis tomentella with potential anti-hepatoma and antibacterial activities

Six undescribed isoquinolines, including one rarely reported N-benzyl isoquinoline together with sixteen known ones were isolated from C. tomentella. Their planar structures and absolute configurations were elucidated by extensive analyses of UV, IR, NMR, HRESIMS, DP4+ probability analysis as well as ECD calculations. Biological evaluations revealed that 3,4-2H-tomentelline C (6) showed significant cytotoxicity (IC₅₀ = 7.42 μM) against the HepG2 cell line while (1'R, 2'S)-coptichine B (3) exhibited stronger antibacterial activities.

Mining Therapeutic Efficacy from Treasure Chest of Biodiversity and Chemodiversity: Pharmacophylogeny of Ranunculales Medicinal Plants

Ranunculales, comprising of 7 families that are rich in medicinal species frequently utilized by traditional medicine and ethnomedicine, represents a treasure chest of biodiversity and chemodiversity. The phylogenetically related species often have similar chemical profile, which makes them often possess similar therapeutic spectrum. This has been validated by both ethnomedicinal experiences and pharmacological investigations. This paper summarizes molecular phylogeny, chemical constituents, and therapeutic applications of Ranunculales, i.e., a pharmacophylogeny study of this representative medicinal order. The phytochemistry/metabolome, ethnomedicine and bioactivity/pharmacology data are incorporated within the phylogenetic framework of Ranunculales. The most studied compounds of this order include benzylisoquinoline alkaloid, flavonoid, terpenoid, saponin and lignan, etc. Bisbenzylisoquinoline alkaloids are especially abundant in Berberidaceae and Menispermaceae. The most frequent ethnomedicinal uses are arthritis, heat-clearing and detoxification, carbuncle-abscess and sore-toxin. The most studied bioactivities are anticancer/cytotoxic, antimicrobial, and anti-inflammatory activities, etc. The pharmacophylogeny analysis, integrated with both traditional and modern medicinal uses, agrees with the molecular phylogeny based on chloroplast and nuclear DNA sequences, in which Ranunculales is divided into Ranunculaceae, Berberidaceae, Menispermaceae, Lardizabalaceae, Circaeasteraceae, Papaveraceae, and Eupteleaceae families. Chemical constituents and therapeutic efficacy of each taxonomic group are reviewed and the underlying connection between phylogeny, chemodiversity and clinical uses is revealed, which facilitate the conservation and sustainable utilization of Ranunculales pharmaceutical resources, as well as developing novel plant-based pharmacotherapy.

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.

13,13a-seco-protoberberines from the tubers of Corydalis yanhusuo and their anti-inflammatory activity

Six undescribed protoberberine derivatives including two pairs of enantiomers, named yanhusanines G-L, along with fifteen reported protoberberine alkaloids, were isolated from the tubers of Corydalis yanhusuo. Among them, yanhusanines H-L feature a unique 13,13a-seco skeleton which is rare in nature. Their structural elucidations were achieved by extensive spectroscopic analysis and quantum chemistry calculations. A biogenetic route for yanhusanines H-L was proposed. Bioassay results showed that yanhusanine J exhibited potent inhibitory effect against the nitric oxide (NO) production in lipopolysaccharide (LPS) induced RAW 264.7 cells (IC₅₀ = 2.25 ± 1.32 μM). Western blot analysis demonstrated that yanhusanine J exerted its anti-inflammatory effect via suppressing the nuclear factor kappa B (NF-κB) pathway, together with the decrease of the inflammatory factors TNF-α, IL-6 and IL-1β. Furthermore, molecular simulation docking indicated that yanhusanine J had strong interaction with the active site of the inducible nitric oxide synthase (iNOS) protein.

Distribution of Therapeutic Efficacy of Ranunculales Plants Used by Ethnic Minorities on the Phylogenetic Tree of Chinese Species

The medicinal properties of plants can be evolutionarily predicted by phylogeny-based methods, which, however, have not been used to explore the regularity of therapeutic effects of Chinese plants utilized by ethnic minorities. This study aims at exploring the distribution law of therapeutic efficacy of Ranunculales plants on the phylogenetic tree of Chinese species. We collected therapeutic efficacy data of 551 ethnomedicinal species belonging to five species-rich families of Ranunculales; these therapeutic data were divided into 15 categories according to the impacted tissues and organs. The phylogenetic tree of angiosperm species was used to analyze the phylogenetic signals of ethnomedicinal plants by calculating the net relatedness index (NRI) and nearest taxon index (NTI) in R language. The NRI results revealed a clustered structure for eight medicinal categories (poisoning/intoxication, circulatory, gastrointestinal, eyesight, oral, pediatric, skin, and urinary disorders) and overdispersion for the remaining seven (neurological, general, hepatobiliary, musculoskeletal, otolaryngologic, reproductive, and respiratory disorders), while the NTI metric identified the clustered structure for all. Statistically, NRI and NTI values were significant in 5 and 11 categories, respectively. It was found that Mahonia eurybracteata has therapeutic effects on all categories. iTOL was used to visualize the distribution of treatment efficacy on species phylogenetic trees. By figuring out the distribution of therapeutic effects of Ranunculales medicinal plants, the importance of phylogenetic methods in finding potential medicinal resources is highlighted; NRI, NTI, and similar indices can be calculated to help find taxonomic groups with medicinal efficacy based on the phylogenetic tree of flora in different geographic regions.

Roles of Alkaloids from Medicinal Plants in the Management of Diabetes Mellitus

Medicinal plants play a fundamental part in health sectors via the management of different infectious diseases because of their wide plenitude wellspring of bioactive phytochemicals. Research activities on them have got attention throughout the world in the present days in search of low-cost and safe compounds for the management of diabetes. This is the literature-based analysis of alkaloids from medicinal plants in preventive or treatment approaches to diabetes. The most abundant and diversified group of secondary metabolites, i.e., alkaloids, show antidiabetic activity through the inhibition of enzymes (α-amylase, α-glucosidase, aldose reductase, dipeptidyl peptidase-IV, and protein tyrosine phosphatase-1B); inhibition of advanced glycation end products; increment of insulin secretion and its sensitivity; enhancement of glucose uptake; and their antioxidant ability. The study is useful for the examination of dynamic alkaloids for the advancement of a new medication for mankind.