Heme Oxygenase-1-Inducing Activity of 4-Methoxydalbergione and 4'-Hydroxy-4-methoxydalbergione from Dalbergia odorifera and Their Anti-inflammatory and Cytoprotective Effects in Murine Hippocampal and BV2 Microglial Cell Line and Primary Rat Microglial Cells

Rapid identification of chemical components and screening of acetylcholinesterase inhibitors from Dalbergia odorifera based on mass defect and diagnostic ion filtering strategy, affinity ultrafiltration, and liquid chromatography-tandem mass spectrometry

Dalbergia odorifera is a natural product rich in pharmacological ingredients, but the comprehensive characterization and rapid profiling of active components remain a challenge. Thus, an integrated data mining and identification strategy was exploited to efficiently identify the chemical constituents and screen acetylcholinesterase inhibitors (AChEIs) through affinity ultrafiltration and ultra-high-performance liquid chromatography-mass spectrometry (AUF-UHPLC-MS). As a result, polygonal mass defect filtering, diagnostic product ions, and neutral loss rules were created for rapid structural classification and component identification. A total of 140 flavonoids were tentatively characterized, including 41 isoflavonoids, 23 flavanones, 21 isoflavans, 19 flavones and flavonols, 13 neoflavonoids, 11 isoflavanones, seven flavone glycosides, and five chalcones. Subsequently, six natural AChEIs including tectorigenin, fisetin, dalbergin, pterostilbene, isoliquiritigenin, and biochanin A were screened out using AUF-UHPLC-MS and molecular docking. Meanwhile, the AChE inhibitory activities of the six compounds were assessed in vitro, tectorigenin, fisetinand, and dalbergin have moderate inhibitory activity. In conclusion, a novel strategy for systematic characterization and further screening of active compounds in natural products was established, which provides a material basis for quality control of Dalbergia odorifera.

4‑Methoxydalbergione inhibits esophageal carcinoma cell proliferation and migration by inactivating NF‑κB

4‑Methoxydalbergione (4‑MD) can inhibit the progression of certain types of cancer; however, its effects on esophageal cancer (EC) remain unclear. The present study aimed to investigate the inhibitory effect of 4‑MD on EC and its molecular mechanism. ECA‑109 and KYSE‑105 cells were treated with or without lipopolysaccharide (LPS) and 4‑MD. Cell Counting Kit‑8 and colony formation assays were used to analyze cell proliferation. Wound healing assay was performed to evaluate cell migration. ELISA and western blotting were performed to measure the expression levels of NF‑κB and inflammatory cytokines. In cells treated with 4‑MD, proliferation and migration were significantly inhibited, the levels of inflammatory cytokines were downregulated and the NF‑κB signaling pathway was inactivated. Notably, proliferation, migration, inflammation and NF‑κB were promoted by LPS, whereas 4‑MD reversed the increases induced by LPS in EC cells. In conclusion, 4‑MD may attenuate the proliferation and migration of EC cells by inactivating the NF‑κB signaling pathway.

Dalbergiones lower the inflammatory response in oral cells in vitro

Objectives

Periodontitis is a global health burden that underlines the demand for anti-inflammatory treatment. Dalbergia melanoxylon being a rich source of flavonoids has been widely used in traditional medicine but the potential anti-inflammatory activity of its dalbergiones remains to be shown.

Material and methods

We have isolated 3′-hydroxy-4,4′-dimethoxydalbergione, 4-methoxydalbergione, and 4′-hydroxy-4-methoxydalbergione from Dalbergia melanoxylon and tested their potential anti-inflammatory activity.

Results

All dalbergiones are potent inhibitors of an LPS-induced inflammatory response of RAW 264.7 macrophages. This is specified by IL1β and IL6 production, and the p65 nuclear translocation. Consistently, in primary macrophages, the dalbergiones caused an M1-to-M2 polarization switch indicated by the decreased ration of IL1β and IL6 versus arginase 1 and YM1 expression. To implement oral cells, we have used gingival fibroblasts exposed to IL1β and TNFα. Consistently, all dalbergiones reduced the expression of IL6 and IL8 as well as the nuclear translocation of p65.

Conclusion

These findings increase the accumulating knowledge on dalbergiones and extend it towards its capacity to lower the inflammatory response of oral cells.

Clinical relevance

These findings are another piece of evidence that supports the use of herbal medicine to potentially lower inflammatory events related to dentistry.

4-Methoxydalbergione is a potent inhibitor of human astroglioma U87 cells in vitro and in vivo

Astroglioma is the most common primary tumor in the central nervous system without effective treatment strategies. Temozolomide (TMZ) is a chemotherapeutic drug to treat astroglioma but exhibits low potency and has side effects. Therefore, there is an urgent need to develop new compounds to treat astroglioma. Dalbergia sissoo Roxb was the source of Dalbergia odorifera in traditional Chinese medicine (TCM) and has been clinically used as an anti-tumor medicine. 4-Methoxydalbergione (4MOD) is purified from Dalbergia sissoo Roxb., and shows an inhibitory effect on osteosarcoma, but its effects on astroglioma have not been reported. Here, we evaluate its anti-astroglioma effects on both in vitro and in vivo models. In cultured astroglioma U87 cells, 4MOD inhibited cell proliferation and induced cell apoptosis in a time- and concentration-dependent manner. Compared with TMZ, 4MOD exhibited a tenfold greater potency of anti-astroglioma effects. 4MOD effectively stalled the cell cycle in G2 phase. Transcriptome sequencing (RNA-seq) showed that 4MOD upregulated 158 genes and downregulated 204 genes that are mainly enriched in cell membrane, cell division, cell cycle, p53, TNF, and MAPK signaling pathways, which may underlie its anti-tumor mechanisms. In a nude mouse xenograft model transplanted with U87 cells, 10 mg/kg 4MOD slowed down tumor growth rate, while at 30 mg/kg dose, it reduced tumor size. Collectively, this study demonstrates that 4MOD is a potent native compound that remarkably inhibits U87 astroglioma growth in both in vitro and in vivo models.

Chemical Analysis of the Ingredients of 20% Aqueous Ethanol Extract of Nardostachys jatamansi through Phytochemical Study and Evaluation of Anti-Neuroinflammatory Component

Nardostachys spp. have been widely used in Asia as a folk medicine. In particular, the extracts of Nardostachys jatamansi, a species that grows in China, India, and Tibet, have been used to treat mental disorders, hyperlipidemia, hypertension, and convulsions. In this investigation, the potential of 20% aqueous ethanol extract of N. jatamansi (NJ20) as a botanical drug was explored by chemically investigating its constituents and its anti-neuroinflammatory effects on lipopolysaccharide- (LPS-) induced in vitro and in vivo models. Nine secondary metabolites were isolated and identified from NJ20, and quantitative analysis of these metabolites revealed desoxo-narchinol A as the major constituent. In LPS-challenged cells, pretreatment with NJ20 inhibited the LPS-induced excessive production of proinflammatory mediators, such as nitric oxide, prostaglandin E₂, interleukin- (IL-) 1β, IL-6, and tumor necrosis factor-α. NJ20 also attenuated the overexpression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2. Additionally, pre-intraperitoneal injection of NJ20 downregulated the mRNA overexpression of IL-1β, IL-6, and iNOS in the prefrontal cortex, hypothalamus, and hippocampus of the LPS-stimulated C57BL/c mouse model. Chemical and biological investigations of NJ20 revealed that it is a potential inhibitor of LPS-induced neuroinflammatory responses in microglial cells and mouse models. The major active constituent of NJ20, desoxo-narchinol A, demonstrated anti-neuroinflammatory effects. Hence, our findings indicate that NJ20 may be a promising herbal mixture for developing a functional product and/or herbal drug for treating neuroinflammatory diseases.

Quality markers based on phytochemical analysis and anti-inflammatory screening: An integrated strategy for the quality control of Dalbergia odorifera by UHPLC-Q-Orbitrap HRMS

BACKGROUND

Quality control, key for the clinical application of traditional Chinese medicines (TCMs), should be connected to the authentication and efficacy of TCMs. The heartwood of Dalbergia odorifera has been widely used to treat inflammation-related diseases. However, in the Chinese pharmacopeia, only the total volatile oil, which does not sufficiently reflect the clinical efficacy, is used as a quality control indicator.

PURPOSE

Establishing a "phytochemical-specificity-effectiveness-Q-marker" analytical strategy to improve the quality control of D. odorifera.

METHODS

Combined with biosynthetic pathway analysis, phytochemical compositions identified by UHPLC-Q-Orbitrap HRMS were used to build substantial phytochemical groups and further discover specific Q-markers. Then, lipopolysaccharide-stimulated RAW 264.7 cells were used to screen effective anti-inflammatory ingredients. Finally, a UHPLC-HRMS method was developed and validated to quantify the selected Q-markers in D. odorifera samples.

RESULTS

Along the constructed biosynthetic pathways, 93 phytochemical components were identified in D. odorifera, including 7 chalcones, 13 flavanones, 21 isoflavones, 21 isoflavanones, 3 flavonols, 19 neoflavones, etc. Among them, 31 compounds representing these 6 categories were further evaluated for their anti-inflammatory activities. It revealed that the extract of D. odorifera and nine flavonoids in the noncytotoxic range could alleviated lipopolysaccharide-stimulated inflammation in RAW 264.7 cells by decreasing the production of proinflammatory mediators such as nitric oxide and interleukin-6. Notably, neoflavones, as species-specific components, exhibited superior anti-inflammatory activities among the representative compounds. Finally, 12 Q-markers (butin, liquiritigenin, eriodictyol, melanettin, naringenin, butein, genistein, 4'-hydroxy-4-methoxydalbergione, isoliquiritigenin, 2,4-dihydroxy-5-methoxybenzophenone, medicarpin, and pinocembrin), which reflect specificity and effectiveness, were successfully quantified in 10 batches of samples from different origins. The origins and consistency of D. odorifera could be efficiently discriminated by hierarchical cluster analysis (HCA).

CONCLUSION

The analysis strategy that combines phytochemical analysis with anti-inflammatory screening clarified the therapeutic material basis and discovered Q-markers, which possibly offers a more comprehensive quality assessment of D. odorifera.

Natural Antioxidant and Anti-Inflammatory Compounds in Foodstuff or Medicinal Herbs Inducing Heme Oxygenase-1 Expression

Heme oxygenase-1 (HO-1) is an inducible antioxidant enzyme that catalyzes heme group degradation. Decreased level of HO-1 is correlated with disease progression, and HO-1 induction suppresses development of metabolic and neurological disorders. Natural compounds with antioxidant activities have emerged as a rich source of HO-1 inducers with marginal toxicity. Here we discuss the therapeutic role of HO-1 in obesity, hypertension, atherosclerosis, Parkinson's disease and hepatic fibrosis, and present important signaling pathway components that lead to HO-1 expression. We provide an updated, comprehensive list of natural HO-1 inducers in foodstuff and medicinal herbs categorized by their chemical structures. Based on the continued research in HO-1 signaling pathways and rapid development of their natural inducers, HO-1 may serve as a preventive and therapeutic target for metabolic and neurological disorders.

Neuroprotective and Anti-Inflammatory Effects of Kuwanon C from Cudrania tricuspidata Are Mediated by Heme Oxygenase-1 in HT22 Hippocampal Cells, RAW264.7 Macrophage, and BV2 Microglia

Heme oxygenase (HO)-1 is a detoxifying phase II enzyme that plays a role in both inflammatory and oxidative stress responses. Curdrania tricuspidata is widespread throughout East Asia and is used as a therapeutic agent in traditional medicine. We investigated whether treatment with sixteen flavonoid or xanthone compounds from C. tricuspidata could induce HO-1 expression in HT22 hippocampal cells, RAW264.7 macrophage, and BV2 microglia. In these compounds, kuwanon C showed the most remarkable HO-1 expression effects. In addition, treatment with kuwanon C reduced cytoplasmic nuclear erythroid 2-related factor (Nrf2) expression and increased Nrf2 expression in the nucleus. Significant inhibition of glutamate-induced oxidative injury and induction of reactive oxygen species (ROS) occurred when HT22 hippocampal cells were pretreated with kuwanon C. The levels of inflammatory mediator and cytokine, which increased following lipopolysaccharide (LPS) stimulation, were suppressed in RAW264.7 macrophage and BV2 microglia after kuwanon C pretreatment. Kuwanon C also attenuated p65 DNA binding and translocation into the nucleus in LPS-induced RAW264.7 and BV2 cells. The anti-inflammatory, anti-neuroinflammatory, and neuroprotective effects of kuwanon C were reversed when co-treatment with HO-1 inhibitor of tin protoporphyrin-IX (SnPP). These results suggest that the neuroprotective and anti-inflammatory effects of kuwanon C are regulated by HO-1 expression.

Anti-inflammatory Metabolites from Chaetomium nigricolor

Twelve metabolites were obtained from the culture media of Chaetomium nigricolor, including a new furan derivative, methyl succinyl Sumiki's acid (1), and two new atropisomers of the previously reported bis-naphtho-γ-pyrones, (aS)-asperpyrone A and (aS)-fonsecinone A (2 and 3). The structures were elucidated by spectroscopic, chemical, and chiroptical techniques. Compounds 2 and 3 inhibited nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 macrophages. Compound 2 was found to inhibit nuclear factor-kappa B and c-Jun N-terminal kinase activation, in turn suppressing pro-inflammatory mediators and cytokines including nitric oxide, prostaglandin E₂, interleukin (IL)-1β, tumor necrosis factor-α, IL-6, and IL-12.

Anti‑inflammatory role of Prunus persica L. Batsch methanol extract on lipopolysaccharide‑stimulated glial cells

Glial cells are the resident immune cells of the central nervous system. Reactive glial cells release inflammatory mediators that induce neurotoxicity or aggravate neurodegeneration. Regulation of glial activation is crucial for the initiation and progression of neuropathological conditions. Constituents of the peach tree (Prunus persica L. Batsch), which has a global distribution, have been found to exert therapeutic effects in pathological conditions, such as rashes, eczema and allergies. However, the therapeutic potential of its aerial parts (leaves, fruits and twigs) remains to be elucidated. The present study aimed to evaluate the anti-inflammatory role of P. persica methanol extract (PPB) on lipopolysaccharide (LPS)-stimulated glial cells. High-performance liquid chromatography coupled with tandem mass spectrometry analysis showed that PPB contained chlorogenic acid and catechin, which have antioxidant properties. Western blot and reverse transcription polymerase chain reaction results indicated that PPB reduced the transcription of various proinflammatory enzymes (nitric oxide synthase and cyclooxygenase-2) and cytokines [tumor necrosis factor-α, interleukin (IL)-1β and IL-6] in LPS-stimulated BV2 cells. In addition, PPB inhibited the activation of NF-κB and various mitogen-activated protein kinases required for proinflammatory mediator transcription. Finally, nitrite measurement and immunocytochemistry results indicated that PPB also suppressed nitrite production and NF-κB translocation in LPS-stimulated primary astrocytes. Thus, PPB may be used as a potential therapeutic agent for neurodegenerative diseases and neurotoxicity via the suppression of glial cell activation.

Dalbergia odorifera: A review of its traditional uses, phytochemistry, pharmacology, and quality control

ETHNOPHARMACOLOGICAL RELEVANCE

Dalbergia odorifera, a traditional herbal medicine, has long been used in China for dissipating blood stasis, regulating the flow of qi, and relieving pain.

AIM OF THIS REVIEW

This review aims to provide comprehensive and up-to-date information about the traditional uses, phytochemistry, pharmacology, and quality control of D. odorifera. Additionally, perspectives for possible future investigations on D. odorifera are also discussed.

MATERIALS AND METHODS

Information on D. odorifera was obtained from a library database and electronic searches (e.g., Elsevier, Springer, ScienceDirect, Wiley, Web of Science, PubMed, Google Scholar, China Knowledge Resource Integrated).

RESULTS

According to classical Chinese herbal texts and the Chinese Pharmacopoeia, D. odorifera promotes blood circulation, relieves pain, and eliminates blood stasis, and it can be used to treat cardio-cerebrovascular diseases in traditional Chinese medicine prescriptions. The chemical constituents of D. odorifera have been well studied, with approximately 175 metabolites having been identified, including flavonoids, phenols, arylbenzofurans, and quinones. The species also contains well-studied volatile oil. Its flavonoids and volatile oil are generally considered to be essential for its pharmacological activity. Modern pharmacology research has confirmed that isolated components and crude extracts of D. odorifera possess wide-ranging pharmacological effects, including anti-inflammatory, anti-angina, anti-oxidative, and other activities. Additionally, there are few quality control studies on D. odorifera.

CONCLUSIONS

To date, significant progress has been made in D. odorifera phytochemistry and pharmacology. Thus, modern pharmacological research has provided some evidence for local or traditional uses. D. odorifera also showed therapeutic potential in cardiovascular and coronary heart diseases. However, the present findings are insufficient to explain its mechanisms of action. Additionally, the mechanism of heartwood formation, artificial induction technology for heartwood production, and quality control of D. odorifera require further detailed research.

Desoxo-narchinol A and Narchinol B Isolated from Nardostachys jatamansi Exert Anti-neuroinflammatory Effects by Up-regulating of Nuclear Transcription Factor Erythroid-2-Related Factor 2/Heme Oxygenase-1 Signaling

We previously reported that desoxo-narchinol A and narchinol B from Nardostachys jatamansi DC (Valerianaceae) inhibited the production of nitric oxide (NO) and prostaglandin E₂ (PGE₂), and the expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 protein in lipopolysaccharide (LPS)-stimulated BV2 and primary microglial cells. In this study, we aimed to elucidate the molecular mechanism underlying the anti-neuroinflammatory effects of desoxo-narchinol A and narchinol B. These two compounds inhibited the nuclear factor (NF)-κB pathway, by repressing the phosphorylation and degradation of inhibitor kappa B (IκB)-α, nuclear translocation of the p65/p50 heterodimer, and DNA-binding activity of the p65 subunit. Furthermore, both compounds induced heme oxygenase-1 (HO-1) protein expression, which was mediated by the activation of nuclear transcription factor erythroid-2-related factor 2 (Nrf2). Activation of the Nrf2/HO-1 pathway by desoxo-narchinol A was shown to be regulated by increased phosphorylation of p38 and extracellular signal-regulated kinase (ERK), whereas only p38 was involved in narchinol B-induced activation of the Nrf2/HO-1 pathway. In addition, phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling was also involved in the activation of HO-1 by desoxo-narchinol A and narchinol B. These compounds also increased the phosphorylation of glycogen synthase kinase 3 beta (GSK3β) at serine-9 residue, following phosphorylation of Akt. The anti-neuroinflammatory effect of desoxo-narchinol A and narchinol B was partially blocked by a selective HO-1 inhibitor, suggesting that this effect is partly mediated by HO-1 induction. In addition, both compounds also induced HO-1 protein expression in rat-derived primary microglial cells, which was correlated with their anti-neuroinflammatory effects in LPS-stimulated primary microglial cells. In conclusion, desoxo-narchinol A and narchinol B are potential candidates for the development of preventive agents for the regulation of neuroinflammation in neurodegenerative diseases.