Abietane diterpenoids from Dracocephalum moldavica L. and their anti-inflammatory activities in vitro

Abietane diterpenoids from Caryopteris incana (Thunb.) Miq. And their HIF-2α inhibitory activities in vitro

Eleven previously undescribed abietane-type diterpenoids, named caryopincanoids A-K (1-11), together with five known compounds, were isolated from the EtOH extract of the aerial parts of Caryopteris incana (Thunb.) Miq. Their structures were elucidated on the basis of comprehensive spectroscopic data, NMR calculations, and ECD calculations. The inhibitory activities of all compounds against HIF-2α gene expression in 786-O cells were tested by luciferase assay. Compounds 7, 9, 15, and 16 showed significant inhibitory effects with IC50 values ranging from 12.73 to 23.80 μM. The preliminary structure-activity relationship of these compounds was also discussed.

Selection of Reference Genes for Expression Normalization by RT-qPCR in Dracocephalum moldavica L

Dracocephalum moldavica is widely used as an ornamental, medicine, and perfume in industry. Real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) is widely and accurately utilized for gene expression evaluations. Selecting optimal reference genes is essential for normalizing RT-qPCR results. However, the identification of suitable reference genes in D. moldavica has not been documented. A total of 12 reference genes in D. moldavica were identified by PEG6000 (15%) treatment under hypertonia conditions in different tissues (roots, stem, leaves, flower, seeds and sepal) and during three stages of flower development, then used to validate the expression stability. There were four algorithms (delta Ct, geNorm, NormFinder, and BestKeeper) used to analyze the stability. Finally, the RefFinder program was employed to evaluate the candidate reference genes' stability. The results showed that ACTIN, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and EF1α (elongation factor-1α) were stable reference genes under the PEG6000 treatment. Heat shock protein 70 (HSP70) was the most stable gene across different flower development stages. ADP-ribosylation factor (ARF) was the most stable gene in different tissues and total samples. This study provides reliable gene expression studies for future research in D. moldavica.

Chemical Constituents of Ajuga Lupulina and their Anti-Ferroptosis Activity

Five new compounds (1, 2, 7, 12, and 16), along with fifteen known ones, were isolated from Ajuga lupulina Maxim. Their structures were revealed by analysing spectroscopic data (MS, NMR), and experimental and calculated ECD spectra was used to deduce the absolute configuration. Compound 16, with eight carbon atoms, was firstly isolated from the nature. All the isolates were evaluated for their inhibitory effect on RSL3-induced ferroptosis in HT22 mouse hippocampal neuronal cells. Among them, the abietane-type diterpenoids (7-11) significantly inhibited ferroptosis with EC50 values of 0.83 μM, 2.05 μM, 0.96 μM, 1.47 μM, and 1.19 μM, respectively.

Dracocephalum moldavica L.: An updated comprehensive review of its botany, traditional uses, phytochemistry, pharmacology, and application aspects

Dracocephalum moldavica, known as Xiang-qing-lan (in Chinese), is a traditional folk medicine, which was commonly used by Mongolian and Xinjiang Uyghurs area. Dracocephalum moldavica has the effects of purging liver fire, clearing stomach heat, hemostasis. It is used for treating insufficient heart and blood, weakened brain function, weak feeling and spirit disease etc. This review aimed to summarize the botany, traditional uses, phytochemistry, pharmacology and application of Dracocephalum moldavica, which expected to provide theoretical support for future utilization and highlight the further investigation of this vital plant. In addition to the essential oil, approximately 154 compounds have been isolated and identified from aerial parts of the Dracocephalum moldavica, including flavonoids, terpenoids, lignans, phenylpropanoids, phenols, glycosides, polysaccharide and other compounds. Extensive pharmacological activities of the extracts or compounds of Dracocephalum moldavica in vivo and in vitro were confirmed including cardiovascular protection, antioxidative, antimicrobial, antifungal, anti-complementary and chronic mountain sickness. Moreover, Dracocephalum moldavica is used in a wide range of applications in food, biological pesticides and cosmetics. In the future, Dracocephalum moldavica needs further study, such as paying more attention to quality control, toxicity, pharmacological mechanism and pharmacokinetics.

Ethnobotanical, Phytochemical, and Pharmacological Properties of the Subfamily Nepetoideae (Lamiaceae) in Inflammatory Diseases

Nepetoideae is the most diverse subfamily of Lamiaceae, and some species are well known for their culinary and medicinal uses. In recent years, there has been growing interest in the therapeutic properties of the species of this group regarding inflammatory illnesses. This study aims to collect information on traditional uses through ethnobotanical, pharmacological, and phytochemical information of the subfamily Nepetoideae related to inflammatory diseases. UNAM electronic resources were used to obtain the information. The analysis of the most relevant literature was compiled and organised in tables. From this, about 106 species of the subfamily are traditionally recognised to alleviate chronic pain associated with inflammation. Pharmacological studies have been carried out in vitro and in vivo on approximately 308 species belonging to the genera Salvia, Ocimum, Thymus, Mentha, Origanum, Lavandula, and Melissa. Phytochemical and pharmacological evaluations have been performed and mostly prepared as essential oil or high polarity extracts, whose secondary metabolites are mainly of a phenolic nature. Other interesting and explored metabolites are diterpenes from the abietane, clerodane, and kaurane type; however, they have only been described in some species of the genera Salvia and Isodon. This review reveals that the Nepetoideae subfamily is an important source for therapeutics of the inflammatory process.

Natural epoxyquinoids: isolation, biological activity and synthesis. An update

Epoxyquinoids are of continuing interest due to their wide natural distribution and diverse biological activities, including, but not limited to, antibacterial, antifungal, anticancer, enzyme inhibitory, and others. The last review on their total synthesis was published in 2017. Since then, almost 100 articles have been published on their isolation from nature and their biological profile. In addition, the review specifically considers synthesis, including total and enantioselective, as well as the development of shorter approaches for the construction of epoxyquinoids with complex chemical architecture. Thus, this review focuses on progress in this area in order to stimulate further research.

Evaluation of the Cytotoxic, Antioxidative and Antimicrobial Effects of Dracocephalum moldavica L. Cultivars

The aim of the present study was to correlate the antioxidant, antimicrobial, and cytotoxic activities of hydroalcoholic extracts obtained from the aerial parts of three Dracocephalum moldavica L. cultivars with their polyphenolic compositions. The polyphenols were identified and quantified using spectrophotometrical methods and LC-MS analysis. Their antioxidant capacities were assessed using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) methods. Their in vitro antimicrobial efficacies were assessed using the agar well diffusion and broth microdilution methods. Their cytotoxicity was investigated on normal diploid foreskin fibroblasts (BJ) and on colorectal adenocarcinoma (DLD-1) cell lines. The results pointed out significant amounts of polyphenolic compounds in the compositions of the tested cultivars, with rosmarinic acid as the main compound (amounts ranging between 5.337 ± 0.0411 and 6.320 ± 0.0535 mg/mL). All three cultivars displayed significant antioxidant (IC₅₀ ranging between 35.542 ± 0.043 and 40.901 ± 0.161 µg/mL for the DPPH assay, and for the FRAP assay 293.194 ± 0.213 and 330.165 ± 0.754 µmol Trolox equivalent/mg dry vegetal material) and antimicrobial potential (especially towards the Gram-positive bacteria), as well as a selective toxicity towards the tumoral line. A significant positive correlation was found between antioxidant activity and the total phenolic acids (r² = 0.987) and polyphenols (r² = 0.951). These findings bring further arguments for strongly considering D. moldavica cultivars as promising vegetal products, which warrants further investigation.

Diterpenoids from Sigesbeckia glabrescens with anti-inflammatory and AChE inhibitory activities

Fourteen previously undescribed diterpenoids, including seven ent-pimarane-type diterpenoids and seven phytane-type diterpenes, together with five known ones, were isolated from the aerial parts of Sigesbeckia glabrescens. The structures and absolute configurations of undescribed compounds were elucidated based on extensive spectroscopic techniques, ECD calculations, Mo₂(OAC)₄-induced ECD, Rh₂(OCOCF₃)₄-induced ECD, calculated ¹³C NMR, and chemical methods. In the anti-inflammatory bioassay, siegetalis H showed potent inhibitory effect on LPS-induced NO production in RAW264.7 murine macrophages with an IC₅₀ value at 17.29 μM. Furthermore, siegetalis H suppressed the protein expression of iNOS and COX-2 in LPS-stimulated RAW264.7 cells. Mechanistically, siegetalis H suppressed the phosphorylation and degradation of IκBα, as well as the activation of the NF-κB signaling pathway. In addition, the AChE inhibition assay displayed that 3-O-acetyldarutigenol had a remarkable inhibitory effect against AChE with an IC₅₀ value at 7.02 μM. Kinetic study on 3-O-acetyldarutigenol indicated that it acted as a mixed-type inhibitor, and the binding mode was explored by molecular docking.

One novel naphthalene derivative and other constituents with anti-complementary activities from the aerial parts of Dracocephalum moldavica

One novel naphthalene derivative, 2-octa-2',4',6'-atriynenaphthalene (1), together with eighteen known compounds (2-19) were isolated from the aerial parts of Dracocephalum moldavica L. Compounds 2, 8, 10, 13, 15-17 and 19 were obtained from the family Lamiaceae for the first time, and compounds 11 and 18 were firstly identified from the genus of Dracocephalum. All the isolates were evaluated for anti-complementary activities through the classical and alternative pathways, and the targets of the most active compounds on the complement activation cascade were also investigated.

Abietane diterpenoids from Phlegmariurus carinatus and their biological activities

Five undescribed abietane diterpenoids, along with eight known analogs, were isolated from Phlegmariurus carinatus. Their structures were unambiguously elucidated by extensive analysis of spectroscopic data and comparison between the literature. The absolute configuration of phlecarinatone C was determined by evaluating ECD spectra. Four undescribed abietane diterpenoids and eight known analogs were tested for their neuroprotective and cytotoxic activities, separately. Teuvincenone C showed potential neuroprotective effect against Hemin-induced HT22 cell damage. Importantly, phlecarinatone C showed pronounced cytotoxic effect against U251 cells in vitro assays. The biological evaluation revealed that phlecarinatone C could inhibit proliferation, migration, and invasion in a concentration-dependent manner of U251 cells. Meanwhile, phlecarinatone C effectively reversed epithelial-to-mesenchymal transition (EMT) and promoted U251 cells apoptosis via a mitochondrial apoptotic pathway. Taken together, phlecarinatone C might be a valuable candidate for anti-metastatic agents against glioblastoma treatment.

Flavones, Flavonols, Lignans, and Caffeic Acid Derivatives from Dracocephalum moldavica and Their In Vitro Effects on Multiple Myeloma and Acute Myeloid Leukemia

Phenolic plant constituents are well known for their health-promoting and cancer chemopreventive properties, and products containing such constituents are therefore readily consumed. In the present work, we isolated 13 phenolic constituents of four different compound classes from the aerial parts of the Moldavian dragonhead, an aromatic and medicinal plant with a high diversity on secondary metabolites. All compounds were tested for their apoptotic effect on myeloma (KMS-12-PE) and AML (Molm-13) cells, with the highest activity observed for the flavone and flavonol derivatives. While diosmetin (6) exhibited the most pronounced effects on the myeloma cell line, two polymethylated flavones, namely cirsimaritin (1) and xanthomicrol (3), were particularly active against AML cells and therefore subsequently investigated for their antiproliferative effects at lower concentrations. At a concentration of 2.5 µM, cirsimaritin (1) reduced proliferation of Molm-13 cells by 72% while xanthomicrol (3) even inhibited proliferation to the extent of 84% of control. In addition, both compounds were identified as potent FLT3 inhibitors and thus display promising lead structures for further drug development. Moreover, our results confirmed the chemopreventive properties of flavonoids in general, and in particular of polymethylated flavones, which have been intensively investigated especially over the last decade.

Moldavica acid A, a new salicylic acid derivative from Dracocephalum moldavica

In this paper, we present the discovery of a novel salicylic acid derivative, moldavica acid A (1), and a new natural dibenzo[b,f]oxepin, moldavica acid B (2), together with four known phenylpropionic acids (3-6) and protocatechuic acid (7) that were isolated from Dracocephalum moldavica L. Their structures were elucidated by comprehensive spectroscopic methods, including infrared and nuclear magnetic resonance. Compound 1 is the first example of salicylic acid linking a carboxylated α-pyrone via an ethyl bridge. Beyond expanding the knowledge of the chemical diversity of D. moldavica, both compounds 1 and 2 were shown to upregulate the expression of Kruppel-like factor 2, which could serve as a prospective therapeutic target for the treatment of atherosclerosis.

Abietane-Type Diterpenoids From Nepeta bracteata Benth. and Their Anti-Inflammatory Activity

Terpenes possess a wide range of structural features and pharmaceutical activities and are promising for drug candidates. With the aim to find bioactive terpene molecules, eight new compounds were isolated from the medicinal plant Nepeta bracteata Benth., including seven new abietane-type diterpenoids (1–7), along with a new ursane-type triterpenoid(8). The structures of compounds 1–8 were elucidated through the detailed spectroscopic analyses of their 1D and 2D NMR and MS data, and the absolute configurations of compounds 1–7 were determined by comparing their experimental and calculated ECD spectra. Compound 1 was a novel degraded carbon diterpene with the disappearing of methyl signal at C-19, while compound 7 possessed a new norabietane-type diterpenoid carbon skeleton with the presence of five-membered lactone arising from ring rearrangement. The anti-inflammatory of all obtained isolates were evaluated on lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and the results of anti-inflammatory activity screening showed that compared with the LPS model group, all compounds were significantly down-regulation the TNF-α inflammatory factor at the specific concentration, except for compound 6.

Isolation and Structural Characterization of Two Polysaccharides from Dracocephalum moldavica and Their Anti-Complementary Activity

The two novel polysaccharides, DMP-1 and DMP-2, with molecular weights of 4.1553×10⁵  kDa and 1.9764×10⁵  kDa, respectively, were isolated from Dracocephalum moldavica. The structural characterization indicated that DMP-1 and DMP-2 shared a similar backbone consisting of →5)-Araf-(1→, Manp-(1→, Glcp-(1→, →2)-Manp-(1→, →6)-Glcp-(1→ and →3,6)-Galp-(1→ with a different molar ratios and triple-helix structures with α- and β-type glycosidic bonds. The anti-complementary activity evaluation showed that DMP-1 and DMP-2 had strong complement inhibition through the classical pathway (CP), alternative pathway (AP) and lectin pathway (LP). Mechanistic studies indicated that DMP-1 can block the activation cascade of the complement system by targeting C2, C3, C5, C9, Factor B and Factor P, and that DMP-2 inhibited complement activation by blocking C2, C3, C4, C5, C9 and Factor B.

Chemical Composition, Antioxidant, and Antimicrobial Activity of Dracocephalum moldavica L. Essential Oil and Hydrolate

Steam distillation was used for the isolation of Dracocephalum moldavica L. (Moldavian dragonhead) essential oil (DMEO). This aromatic herbaceous plant is widespread across the Northern Hemisphere regions and has been utilized in health-improving studies and applications. In addition to the DMEO, the hydrolate (DMH), a byproduct of the distillation process, was also collected. The DMEO and DMH were analyzed and compared in terms of their chemical composition, as well as their in vitro biological activities. The main component in DMEO was geranyl acetate, while geranial was dominant in DMH. The DMEO demonstrated better antioxidant and antimicrobial activities compared with the DMH against Staphylococcus aureus, Escherichia coli, Salmonella Typhimurium, and Listeria monocytogenes, which represent sources of food-borne illness at the global level. The DMEO and DMH show promise as antioxidant and antimicrobial additives to various products.

Dracocephalum moldavica Ethanol Extract Suppresses LPS-Induced Inflammatory Responses through Inhibition of the JNK/ERK/NF-κB Signaling Pathway and IL-6 Production in RAW 264.7 Macrophages and in Endotoxic-Treated Mice

The excessive synthesis of interleukin-6 (IL-6) is related to cytokine storm in COVID-19 patients. Moreover, blocking IL-6 has been suggested as a treatment strategy for inflammatory diseases such as sepsis. Sepsis is a severe systemic inflammatory response syndrome with high mortality. In the present study, we investigated the anti-inflammatory and anti-septic effects and the underlying mechanisms of Dracocephalum moldavica ethanol extract (DMEE) on lipopolysaccharide (LPS)-induced inflammatory stimulation in RAW 264.7 macrophages along with septic mouse models. We found that DMEE suppressed the release of inflammatory mediators NO and PGE₂ and inhibited both the mRNA and protein expression levels of iNOS and COX-2, respectively. In addition, DMEE reduced the release of proinflammatory cytokines, mainly IL-6 and IL-1β, in RAW 264.7 cells by inhibiting the phosphorylation of JNK, ERK and p65. Furthermore, treatment with DMEE increased the survival rate and decreased the level of IL-6 in plasma in LPS-induced septic shock mice. Our findings suggest that DMEE elicits an anti-inflammatory effect in LPS-stimulated RAW 264.7 macrophages and an anti-septic effect on septic mouse model through the inhibition of the ERK/JNK/NF-κB signaling cascades and production of IL-6.