Plant flavonoids: Classification, distribution, biosynthesis, and antioxidant activity

Uncovering the mechanisms of Zhubi decoction against rheumatoid arthritis through an integrated study of network pharmacology, metabolomics, and intestinal flora

ETHNOPHARMACOLOGICAL RELEVANCE

Zhubi Decoction (ZBD) is a modified formulation derived from the classic traditional Chinese medicine prescription "Er-Xian Decoction" documented in the esteemed "Clinical Manual of Chinese Medical Prescription". While the utilization of ZBD has exhibited promising clinical outcomes in treating rheumatoid arthritis (RA), the precise bioactive chemical constituents and the underlying mechanisms involved in its therapeutic efficacy remain to be comprehensively determined.

AIM OF THE STUDY

This study aims to systematically examine ZBD's pharmacological effects and molecular mechanisms for RA alleviation.

MATERIALS AND METHODS

Utilizing the collagen-induced arthritis (CIA) rat model, we comprehensively evaluated the anti-rheumatoid arthritis effects of ZBD in vivo through various indices, such as paw edema, arthritis index, ankle diameter, inflammatory cytokine levels, pathological conditions, and micro-CT analysis. The UPLC-MS/MS technique was utilized to analyze the compounds of ZBD. The potential therapeutic targets and signaling pathways of ZBD in the management of RA were predicted using network pharmacology. To analyze comprehensive metabolic profiles and identify underlying metabolic pathways, we conducted a serum-based widely targeted metabolomics analysis utilizing LC-MS technology. Key targets and predicted pathways were further validated using immunofluorescent staining, which integrated findings from serum metabolomics and network pharmacology analysis. Additionally, we analyzed the gut microbiota composition in rats employing 16 S rDNA sequencing and investigated the effects of ZBD on the microbiota of CIA rats through bioinformatics and statistical methods.

RESULTS

ZBD exhibited remarkable efficacy in alleviating RA symptoms in CIA rats without notable side effects. This included reduced paw redness and swelling, minimized joint damage, improved the histopathology of cartilage and synovium, mitigated the inflammatory state, and lowered serum concentrations of cytokines TNF-α, IL-1β and IL-6. Notably, the effectiveness of ZBD was comparable to MTX. Network pharmacology analysis revealed inflammation and immunity-related signaling pathways, such as PI3K/AKT, MAPK, IL-17, and TNF signaling pathways, as vital mediators in the effectual mechanisms of ZBD. Immunofluorescence analysis validated ZBD's ability to inhibit PI3K/AKT pathway proteins. Serum metabolomics studies revealed that ZBD modulates 170 differential metabolites, partially restored disrupted metabolic profiles in CIA rats. With a notable impact on amino acids and their metabolites, and lipids and lipid-like molecules. Integrated analysis of metabolomics and network pharmacology identified 6 pivotal metabolite pathways and 3 crucial targets: PTGS2, GSTP1, and ALDH2. Additionally, 16 S rDNA sequencing illuminated that ZBD mitigated gut microbiota dysbiosis in the CIA group, highlighting key genera such as Ligilactobacillus, Prevotella_9, unclassified_Bacilli, and unclassified_rumen_bacterium_JW32. Correlation analysis disclosed a significant link between 47 distinct metabolites and specific bacterial species.

CONCLUSION

ZBD is a safe and efficacious TCM formulation, demonstrates efficacy in treating RA through its multi-component, multi-target, and multi-pathway mechanisms. The regulation of inflammation and immunity-related signaling pathways constitutes a crucial mechanism of ZBD's efficacy. Furthermore, ZBD modulates host metabolism and intestinal flora. The integrated analysis presents experimental evidence of ZBD for the management of RA.

Quantitative predictions of protein and total flavonoids content in Tartary and common buckwheat using near-infrared spectroscopy and chemometrics

A rapid method was developed for determining the total flavonoid and protein content in Tartary buckwheat by employing near-infrared spectroscopy (NIRS) and various machine learning algorithms, including partial least squares regression (PLSR), support vector regression (SVR), and backpropagation neural network (BPNN). The RAW-SPA-CV-SVR model exhibited superior predictive accuracy for both Tartary and common buckwheat, with a high coefficient of determination (R2p = 0.9811) and a root mean squared error of prediction (RMSEP = 0.1071) for flavonoids, outperforming both PLSR and BPNN models. Additionally, the MMN-SPA-PSO-SVR model demonstrated exceptional performance in predicting protein content (R2p = 0.9247, RMSEP = 0.3906), enhancing the effectiveness of the MMN preprocessing technique for preserving the original data distribution. These findings indicate that the proposed methodology could efficiently assess buckwheat adulteration analysis. It can also provide new insights for the development of a promising method for quantifying food adulteration and controlling food quality.

Preparation of monoclonal antibody against rhoifolin and its application in enzyme-linked immunosorbent assay of rhoifolin and diosmin

Both rhoifolin and diosmin belong to flavonoids, which are widely present in citrus. Diosmin is not only used in the medical field in the world, but also used as a dietary supplement in the United States. Rhoifolin has a similar structure to diosmin and also exhibits antioxidant and anti-inflammatory properties. In this study, an anti-rhoifolin monoclonal antibody was prepared and an indirect competitive enzyme-linked immunosorbent assay (icELISA) method was established. The half-maximal inhibitory concentration (IC50) of icELISA was determined to be 4.83 ng/mL, and the detection range was 0.97-33.87 ng/mL. The results of UPLC-MS/MS and icELISA generally demonstrate consistency. Moreover, by exploiting the cross-reactivity of the antibody, diosmin in tablets can be detected by icELISA. The results demonstrate that the developed method has good accuracy, reproducibility, and broad application prospects.

Combining widely targeted metabolomics and RNA-sequencing to reveal the function analysis of Phyllanthus emblica Linn. Juice-induced poultry macrophages

This study explored the functional effects of cultivated and wild Phyllanthus emblica Linn juice (PEJ) in HD11 poultry macrophage lines, with the aim of potentially developing cultivated PE and its fruit residue as poultry feed additives. RNA-Seq was used to evaluate the functional differences between cultivated and wild PEJ induced HD11 cells. Both cultivated and wild PEJ could regulate cell replication by histone H1/H2 family genes and host immune response by Toll-like receptor 7 regulation. Wild PEJ inhibited M1-type polarization of host macrophages, while cultivated PEJ promoted M2-type polarization. Metabolites of cultivated and wild PE were identified by widely targeted metabolomics based on liquid chromatography-tandem mass spectrometry. Of the 911 metabolites, 238 differed functionally between cultivated and wild PE. The data provide a theoretical basis for the subsequent development of PE as a functional feed additive in poultry.

Using VIS-NIR hyperspectral imaging and deep learning for non-destructive high-throughput quantification and visualization of nutrients in wheat grains

High-throughput and low-cost quantification of the nutrient content in crop grains is crucial for food processing and nutritional research. However, traditional methods are time-consuming and destructive. A high-throughput and low-cost method of quantification of wheat nutrients with VIS-NIR (400-1700 nm) hyperspectral imaging is proposed in this study. Stepwise linear regression (SLR) was used to predict hundreds of nutrients accurately (R2 > 0.6); results improved when the hyperspectral data was processed with the first derivative. Knockout materials were also used to verify their practical application value. Various nutrients' characteristic wavelengths were mainly concentrated in the visible regions of 400-500 nm and 900-1000 nm. Finally, we proposed an improved pix2pix conditional generative network model to visualize the nutrients distribution and showed better results compared with the original. This research highlights the potential of hyperspectral technology in high-throughput and non-destructive determination and visualization of grain nutrients with deep learning.

Revealing the key antioxidant compounds and potential action mechanisms of Chinese Cabernet Sauvignon red wines by integrating UHPLC-QTOF-MS-based untargeted metabolomics, network pharmacology and molecular docking approaches

In recent years, red wine drinking has become more popular in China owing to its antioxidant effects. However, the key antioxidant compounds and their action mechanisms of Chinese red wines are still unclear. Herein, the antioxidant activities and chemical compositions of 45 Chinese Cabernet Sauvignon red wine samples were determined using chemical antioxidant assays and an UHPLC-QTOF-MS-based untargeted metabolomics method. The key antioxidant compounds in red wines and potential action mechanisms were revealed by integrating network pharmacology and molecular docking approaches. Results showed that there are 8 key antioxidant compounds in the red wine samples. These compounds are involved in several metabolic pathways in the body, particularly PI3K/AKT. What's more, they bind to the core antioxidant targets through hydrogen bonding and hydrophobic interaction. Among them, myricetin, laricitrin, 2,3,8-tri-O-methylellagic acid and AKT1 have the highest binding energies. This study could provide the theoretical basis for further investigation of physiological activities and functions of Chinese red wines.

Overexpression of ZlMYB1 and ZlMYB2 increases flavonoid contents and antioxidant capacity and enhances the inhibition of α-glucosidase and tyrosinase activity in rice seeds

Anthocyanins are natural flavonoids with a high antioxidant power and many associated health benefits, but most rice produce little amounts of these compounds. In this study, 141 MYB transcription factors in 15 chromosomes, including the nucleus-localised ZlMYB1 (Zla03G003370) and ZlMYB2 (Zla15G015220), were discovered in Zizania latifolia. Overexpression of ZlMYB1 or ZlMYB2 in rice seeds induced black pericarps, and flavonoid content, antioxidant capacity, and α-glucosidase and tyrosinase inhibition effects significantly increased compared to those in the control seeds. ZlMYB1 and ZlMYB2 overexpression induced the upregulation of 764 and 279 genes, respectively, and the upregulation of 162 and 157 flavonoids, respectively, linked to a black pericarp phenotype. The expression of flavonoid 3'-hydroxylase and UDP-glycose flavonoid glycosyltransferase, as well as the activities of these enzymes, increased significantly in response to ZlMYB1 or ZlMYB2 overexpression. This study systematically confirmed that the overexpression of ZlMYB1 and ZlMYB2 promotes flavonoid biosynthesis (especially of anthocyanins) in rice.

Biotransformation characteristics of urate-lowering probiotic fermented apple juice and potential regulatory mechanisms for ameliorating hyperuricemia via mediating gut microbiota and metabolic pathways

Hyperuricemia has evolved into a global public health concern, and applying probiotics fermented apple juice holds promise for alleviating this condition. This study aimed to investigate the biotransformation and metabolic features of urate-lowering probiotics sequentially fermented dealcoholized apple juice (PSFA), and assess its ameliorative effects and potential mechanisms on hyperuricemia mice. Results showed that CICC 6074 and 20,292 possessed excellent purine, nucleotide and nucleoside degradation and acid and bile salt resistance; sequential fermentation decreased the fructose in apple juice, and viable counts reached 3.76 × 108 CFU/mL. Histopathological analysis showed that PSFA ameliorated kidney damage in hyperuricemia mice. Furthermore, PSFA significantly reduced Urea, Creatinine and Uric acid levels in hyperuricemia mice; and inhibited xanthine oxidase activity and the expression of pro-inflammatory factors. Importantly, PSFA reversed gut microbiota dysbiosis and raised the abundance of beneficial bacteria (Lactobacillush, Faecalibaculum and Lachnospiraceae_NK4A136_group). KEGG and COG functional prediction results revealed that the potential mechanism of PSFA to ameliorate hyperuricemia may be lipid metabolism and glycolysis pathways.

Anticoccidial activity of the secondary metabolites in alpine plants frequently ingested by wild Japanese rock ptarmigans

The Japanese rock ptarmigan (Lagopus muta japonica) is an herbivorous species of partridges that inhabits only alpine zones. Alpine plants are their main source of food. These alpine plants contain toxic compounds to deter herbivores from consuming them. A previous analysis of the alpine plants frequently consumed by Japanese rock ptarmigans revealed the presence of a unique mixture of secondary metabolites and a novel compound. Additionally, wild Japanese rock ptarmigans are often infected by two species of Eimeria parasites. When these parasites were experimentally administered to Svalbard rock ptarmigans (Lagopus muta hyperborean), which do not feed on alpine plants, the birds exhibited symptoms, such as diarrhea and depression, and in some cases, they died. Although little is known about the pathogenesis of these parasites in wild Japanese rock ptarmigans, it was hypothesized that compounds found in alpine plants, their main food source, may reduce the pathogenicity of Eimeria parasites. In the present study, we evaluated the anticoccidial activity of the compounds derived from alpine plants in vitro using Eimeria tenella, which infects chickens belonging to the same pheasant family, as an experimental model. Twenty-seven natural components were extracted from eight alpine plants. The natural components were added to E. tenella sporozoites and incubated for 24 h to evaluate their direct effect. Additionally, Madin-Darby bovine kidney cells were incubated with sporozoites and natural components for 24 h to evaluate the inhibitory effect of the components on sporozoite cell invasion. Six compounds from four alpine plants decreased sporozoite viability by up to 88.3%, and two compounds inhibited sporozoite invasion into the cells. Although further studies are needed to evaluate the effects of these components against Eimeria infections in vivo, our findings suggest that these alpine plants may reduce the degree of infection by decreasing the number of sporozoites in the intestinal tract.

Functional potential of a new plant-based fermented beverage: Benefits through non-conventional probiotic yeasts and antioxidant properties

Functional foods represent one of the fastest-growing, newer food category, and plant sources with functional properties are increasingly used as analogues of fermented milk-based derivatives. In this study, blended wort-rooibos beverages fermented with probiotic yeasts are proposed for the first time. Benefits of functional, non-conventional Lachancea thermotolerans (Lt101), Kazachstania unispora (Kum3-B3), Meyerozyma guilliermondii (Mg112), Meyerozyma caribbica (Mc58) and Debaryomyces hansenii (Dh36) yeast strains and the content of bioactive metabolites were evaluated. Viability tests on the probiotic yeasts confirmed previous results obtained in other matrices. The functional footprint of probiotic yeasts Lt101, Mg112 and Dh36 was confirmed by a balanced nutritional profile of the final drinks, also supported by aromatic and sensory analyses. In vitro estimated glycaemic index ranged between 77 % and 87 % without any influence on glycaemic response. Strains Dh36, Mc58, Kum3-B3 and Mg112 showed high antioxidant capacity and high total phenolic content, supporting the health promoting effect of the beverages.

Fabrication, characterization, and bioactivity of self-assembled carrier-free colloidal dispersions from Citrus × Limon 'Rosso' essential oil and tea polyphenols

Carrier-free nanodelivery systems are fully self-assembled from active ingredients through interactions, offering the advantages of green, safe, and large-scale manufacturing. To improve the dispersion of Citrus × limon 'Rosso' peel essential oil (CEO) in water and boost the biological activity of CEO and tea polyphenols (TP), self-assembled CEO-TP colloidal dispersions (CEO-TP Colloids) were fabricated through sonication without surfactants or carriers. The optimal CEO and TP concentrations in the CEO-TP Colloids were determined to be 10.0 and 20.0 mg/mL by particle size and stability analyzer, respectively. The CEO self-assembled with TP to form spherical nanoparticles through hydrophobic and hydrogen-bonding interactions, whereas the CEO in CEO-TP Colloids weakened TP intramolecular aggregation. Meanwhile, the CEO-TP Colloids showed synergistic effects with better antibacterial, cellular antioxidant, and anti-inflammatory activities than single components. This study opens up the possibility of carrier-free co-delivery of hydrophobic and hydrophilic active components developed into food-grade formulations with multiple bioactivities.

Combined metabolomics and bioactivity assays kernelby-productsof two native Chinese cherry species: The sources of bioactive nutraceutical compounds

Cherry kernels are a by-product of cherries that are usually discarded, leading to waste and pollution. In this study, the chemical composition of 21 batches of cherry kernels from two different cherry species was analyzed using untargeted metabolomics. The in vitro antioxidant activity, cellular antioxidant activity, and antiproliferative activity of these kernel extracts were also determined, and a correlation analysis was conducted between differential compounds and biological activity. A total of 49 differential compounds were screened. The kernels of Prunus tomentosa were found to have significantly higher total phenol, total flavonoid content, and biological activity than those of Prunus pseudocerasus (P < 0.05). Correlation analysis showed that flavonoids had the greatest contribution to biological activity. The study suggests that both species of cherry kernel, particularly Prunus tomentosa, could be a potential source of bioactive compounds that could be used in the pharmaceutical, cosmetic, and food industries.

Flavonoid localization in soybean seeds: Comparative analysis of wild (Glycine soja) and cultivated (Glycine max) varieties

Wild soybean (Glycine soja) is known for its high flavonoid contents, yet the distribution of flavonoids in the seeds is not well understood. Herein, we utilized matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) and metabolomics methods to systematically investigate flavonoid differences in the seed coats and embryos of G. soja and G. max. The results of flavonoid profiles and total flavonoid content analyses revealed that flavonoid diversity and abundance in G. soja seed coats were significantly higher than those in G. max whereas the levels were similar in embryos. Specifically, 23 unique flavonoids were identified in the seed coats of G. soja, including procyanidins, epicatechin derivatives, and isoflavones. Using MALDI-MSI, we further delineated the distribution of the important flavonoids in the cotyledons, hypocotyls, and radicles of the two species. These findings imply that G. soja holds considerable breeding potential to enhance the nutritional and stress resistance traits of G. max.

Metabolic basis for superior antioxidant capacity of red-fleshed peaches

Peach fruit is an important natural source of phenolic compounds that are well-known to have health benefits, but their metabolic basis remain elusive. Here, we report on phenolic compounds accumulation and antioxidant activity of ripe fruits in peach. A considerable variation in phenolic compounds content was observed among peach germplasm, with significantly higher levels detected in red-fleshed peaches compared to non-red-fleshed peaches. Antioxidant activity of crude extracts from ripe fruits showed significant differences among peach germplasm, with red-fleshed peaches having the strongest antioxidant activity. Intriguingly, it was observed that total phenolics instead of anthocyanins were strongly associated with antioxidant activity. Phenolic compounds content and antioxidant activity showed dynamic changes throughout fruit development, and these were much higher in the peel than in the flesh. Metabolomic analysis unveiled a coordinated accumulation of anthocyanins as well as key components of flavonoids and phenolic acids, which endows red-fleshed peaches with superior antioxidant activity.

Effects of derivatization and probiotic transformation on the antioxidative activity of fruit polyphenols

Fruits contain numerous polyphenols in the form of conjugates, which exhibit low antioxidant activity. Probiotic fermentation is a strategy to improve the antioxidant activity of these conjugated polyphenols by modifying their structure. However, the mechanisms underlying the effects of functional groups and derivatizations on the antioxidative activities of polyphenols and the antioxidation enhancement by probiotic biotransformation haven't been comprehensively explored. This review aimed to explore the structure-antioxidant activity relationships of four functional groups and three derivatizations in flavonoids and phenolic acids. Further, the review elucidated the antioxidant mechanisms underlying the biotransformation of flavonoids and phenolic acids as glycoside, methylated, and ester conjugates by probiotic biotransformation. Deglycosylation, demethylation, and hydrolysis catalyzed by enzymes produced by Bifidobacterium and Lactobacillus facilitated the conversion of conjugated polyphenols into flavonoids and phenolic acids with hydrolyzed forms and highly active functional groups, thereby increasing hydrogen supply and electron transfer capacity to enhance the antioxidant activity.

Biological effects and mechanisms of dietary chalcones: latest research progress, future research strategies, and challenges

Dietary plants are an indispensable part of the human diet, and the various natural active compounds they contain, especially polyphenols, polysaccharides, and amino acids, have always been a hot topic of research among nutritionists. As precursors to polyphenolic substances in dietary plants, chalcones are not only widely distributed but also possess a variety of biological activities due to their unique structure. However, there has not yet been a comprehensive article summarizing the biological activities and mechanisms of dietary chalcones. This review began by discussing the dietary sources and bioavailability of chalcones, providing a comprehensive description of their biological activities and mechanisms of action in antioxidation, anti-inflammation, anti-tumor, and resistance to pathogenic microbes. Additionally, based on the latest research findings, some future research strategies and challenges for dietary chalcones have been proposed, including computer-aided design and molecular docking, targeted biosynthesis and derivative design, interactions between the gut microbiota and chalcones, as well as clinical research. It is expected that this review will contribute to supplementing the scientific understanding of dietary chalcones and promoting their practical application and the development of new food products.

H. pectinata (L.) Poit - Traditional uses, phytochemistry and biological-pharmacological activities in preclinical studies: A systematic review

ETHNOPHARMACOLOGICAL RELEVANCE

H. pectinata (L.) Poit, popularly known as "sambacaitá" or "canudinho", is a plant endemic to north-eastern Brazil. Its aerial parts, leaves and flowers have traditionally been used to treat gastrointestinal disorders, rhinopharyngitis, nasal congestion, bacterial and fungal infections, fever, colic, inflammation, and pain.

AIM OF THE STUDY

The aim of this review was to provide information on the botanical characteristics, ethnomedicinal uses, phytochemistry and biological-pharmacological activities of H. pectinata.

MATERIALS AND METHODS

This systematic review followed the Cochrane Handbook Collaboration and the PRISMA guidelines. The review question was what are the biological-pharmacological activities of H. pectinata presented in non-clinical studies. The search for articles was conducted in the Medline (via PubMed), Embase, Web of Science, Scopus, Virtual Health Library, SciELO, Google Scholar and the Brazilian Digital Library of Theses and Dissertations databases. Two reviewers independently selected the studies that met the inclusion criteria, extracted the data, and assessed the risk of bias of the included studies.

RESULTS

39 articles were included in this review, of which 19 reported in vitro experiments, 16 in vivo studies and 4 in vivo and in vitro experiments. H. pectinata is a plant widely used in folk medicine in north-eastern Brazil for the treatment of various ailments, such as respiratory diseases, gastrointestinal disorders, bacterial and fungal infections, and general inflammation. Supporting its popular use, several in vitro and in vivo pharmacological investigations of the essential oil and extract of H. pectinata have demonstrated their anti-inflammatory, antinociceptive, antioxidant, antidepressant, anticancer, hepatoregenerative, healing, and antimicrobial activities. H. pectinata has been reported to contain 75 bioactive constituents, comprising 9 flavonoids, 54 terpenes, and 12 other compounds.

CONCLUSION

H. pectinata is a plant commonly used in traditional medicine. Phytochemically, it contains several bioactive constituents, including terpenes and flavonoids, and has been shown to have antinociceptive, anti-inflammatory, antimicrobial and antitumour activity, as well as hepatorregenerative and healing effects, and low toxicity.

Anti-inflammatory properties of ophioglonin derived from the fern Ophioglossum vulgatum L. via inactivating NF-κB and MAPK signaling pathways

Medicinal plants contain bioactive compounds that have therapeutic effects on human health. Ophioglossum vulgatum L. is a representative species of the fern genus Ophioglossum that has anti-inflammatory properties as recognized in folk medicine. Herein, we performed a nitric oxide (NO) assay-guided screening in RAW264.7 cells to investigate the active components of the plant. We found that ophioglonin (OPN), a characteristic homoflavonoid of the genus Ophioglossum, is one of the bioactive components. Therefore, we performed a comparative analysis of the isolated compounds and found that OPN has effects similar to those of isolated dihydroquercetin and luteolin at the concentrations tested. The antioxidant and anti-inflammatory activities of OPN were extensively validated using lipopolysaccharide -stimulated RAW264.7 cells, mouse bone marrow-derived macrophages (BMDMs), and peritoneal exudate macrophages (PEMs). In vivo experiments with a carrageenan-induced mouse paw edema model further confirmed the anti-inflammatory effect of OPN. Additionally, we found that OPN and Ophioglossum vulgatum extracts inhibit the activation of signal transducers, NF-ĸB p65, IĸBα, ERK, p38, and JNK, consistent with the findings of pathway enrichment analysis. This work reinforces the anti-inflammatory properties of Ophioglossum vulgatum and indicates that OPN is a promising therapeutic agent for inflammation-associated disorders. Further clinical evaluations, including clinical trials, would be beneficial to validate the anti-inflammatory properties of OPN.

The key to 2,6-dichloro-1,4-benzoquinone reproductive toxicity and green tea detoxification: Covalent binding and competitive binding

Halobenzoquinones (HBQs) are ubiquitous disinfection by-products (DBPs) in chlorinated drinking water with various health risks including reproductive toxicity, while the potential mechanisms are still unclear. Although green tea exhibits common detoxifying properties, its ability to mitigate the toxicity of HBQs still needs to be further deepened and explored. This study attempted to investigate the possible mechanism of the most common HBQ, 2,6-dichloro-1,4-benzoquinone (2,6-DCBQ) induced reproductive toxicity and elucidate the protective effect of green tea using a series of liquid chromatography-tandem mass spectrometry (LC-MS) approaches. Firstly, in vivo experiments showed that 2,6-DCBQ could induce testicular damage in male rats via significantly decreasing sperm-associated Leydig cells and seminiferous tubules. Then, in vitro incubation of 2,6-DCBQ with amino acids suggested that 2,6-DCBQ could bind to proteins via residues of cysteine or lysine and provided five additional modification patterns. Following, proteomics analysis revealed that at least 42 proteins were modified by 2,6-DCBQ, which were mainly enriched in the reproductive system. These results highlighted the significance of covalent protein modification in 2,6-DCBQ reproductive toxicity. Fortunately, we found that catechins (a class of major components of green tea) could competitively bind to 2,6-DCBQ in vivo and in vitro, reducing the amount and type of 2,6-DCBQ-protein adducts, thereby attenuating the reproductive system damage caused by 2,6-DCBQ. This study provides new insights into 2,6-DCBQ-induced reproductive system damage and reveals a new mechanism of green tea detoxification. Moreover, these findings offer potential strategies for alleviating the harmful impacts of environmental toxicants on human health.

Correlation of dietary flavonoid intake with chronic bronchitis, emphysema, and asthma in U.S. adults: A large, national, cross-sectional study

OBJECTIVE

To explore the relationship between dietary flavonoids and bronchitis, emphysema and asthma.

METHOD

A total of 11743 United States adults were extracted from the National Health and Nutrition Examination Survey (NHANES) in 2007-2008, 2009-2010 and 2017-2018. Of these, 47.7% were male and 52.3% female. Dietary flavonoid intake assessed using FDNNS and 24-hour dietary recall data. Inclusion of demographics (gender, age, education, family income), behavioral factors (BMI, smoking, drinking status, diet), chronic disease information (diabetes, hypertension) as covariates to eliminate confounding. Stepwise logistic regression was used to analyze the association between total dietary flavonoid intake and the risk of chronic respiratory disease. Weighted quantile sum regression (WQS) was used to analyze the association between 29 dietary flavonoids and the risk of chronic respiratory disease. Restricted cubic spline was used to analyze the dose-response relationship between dietary flavonoid intake and risk of chronic respiratory disease.

RESULTS

Stepwise logistic regression results showed that higher flavonoid intake in men was associated with a lower risk of CB and asthma (OR of CB: 0.55(0.31-0.97); OR of asthma: 0.72(0.52-0.99)), and WQS results showed a mixed health effect for total flavonoids and chronic respiratory tract in response to the 29 flavonoid fractions (OR of asthma: 0.97(0.94-0.99); OR of emphysema: 0.95(0.90-0.99)). Glycitein had the highest health contribution of 26.2% for emphysema; Eriodictyol had the highest health contribution of 32.13% for asthma, respectively. The RCS showed a dose-response relationship between flavonoids and respiratory tract health. The maximum dose for ingesting flavonoids to gain respiratory health benefits is 1500 mg/d.

CONCLUSION

Higher dietary flavonoid intake was associated with lower chronic respiratory risk in adult U.S. men. Also 29 dietary flavonoid components have an overall health effect on respiratory health. Glycitein and Eriodictyol may have potential health effects on the respiratory system. 1500 mg/day may be the Tolerable Upper Intake Level of dietary flavonoids for respiratory health in U.S. adults.

Transcriptomic Analysis of the Combined Effects of Methyl Jasmonate and Wounding on Flavonoid and Anthraquinone Biosynthesis in Senna tora

Jasmonates, including jasmonic acid (JA) and its derivatives such as methyl jasmonate (MeJA) or jasmonly isoleucine (JA-Ile), regulate plant responses to various biotic and abiotic stresses. In this study, we applied exogenous MeJA onto Senna tora leaves subjected to wounding and conducted a transcriptome deep sequencing analysis at 1 (T1), 3 (T3), 6 (T6), and 24 (T24) h after MeJA induction, along with the pretreatment control at 0 h (T0). Out of 18,883 mapped genes, we identified 10,048 differentially expressed genes (DEGs) between the T0 time point and at least one of the four treatment times. We detected the most DEGs at T3, followed by T6, T1, and T24. We observed the upregulation of genes related to JA biosynthesis upon exogenous MeJA application. Similarly, transcript levels of genes related to flavonoid biosynthesis increased after MeJA application and tended to reach their maximum at T6. In agreement, the flavonols kaempferol and quercetin reached their highest accumulation at T24, whereas the levels of the anthraquinones aloe-emodin, emodin, and citreorosein remained constant until T24. This study highlights an increase in flavonoid biosynthesis following both MeJA application and mechanical wounding, whereas no significant influence is observed on anthraquinone biosynthesis. These results provide insights into the distinct regulatory pathways of flavonoid and anthraquinone biosynthesis in response to MeJA and mechanical wounding.

Protective Effects of Annona Atemoya Extracts on Inflammation, Oxidative Stress, and Renal Function in Cadmium-Induced Nephrotoxicity in Wistar Rats

BACKGROUND

Cadmium (Cd), a highly toxic heavy metal from agricultural activities, and its exposure can lead to impaired renal function by increasing reactive oxygen species. The atemoya fruit is known for its high phenolic and antioxidant compounds. This study aimed to evaluate the effects of atemoya extracts on renal function, oxidative stress parameters, and inflammatory biomarkers in a cadmium-induced nephrotoxicity model.

METHODS

Three aqueous extracts were prepared from different parts of the atemoya fruit: seeds, peel, and pulp. Twenty-five male Wistar rats were allocated into four groups: control, seed, peel, and pulp extracts at 2 g/kg for 25 days. All treatment groups administered intraperitoneal injections of cadmium chloride (CdCl2) (2 mg/kg) to induce renal damage.

RESULTS

The cadmium-treated groups showed decreased creatinine clearance, SOD, CAT, and GPx activities (p < 0.05) and increased serum levels of TNF-α and IL-6 compared to the control group (p < 0.05). The treatment with seed, peel, and pulp extracts increased creatinine clearance (p < 0.05), increased SOD, CAT, and GPx activities (p < 0.05), and reduced serum levels of TNF-α and IL-6 compared to the Cd group (p < 0.05).

CONCLUSIONS

This study supports the use of atemoya as a promising candidate for mitigating nephrotoxicity and highlights the importance of its antioxidant and anti-inflammatory properties in renal health.

Possible protective effect of natural flavanone naringenin-reduced graphene oxide nanosheets on nonalcoholic fatty liver disease

Utilizing naringenin as a safe, natural compound for reducing graphene oxide and to determine whether Nar-RGO more effectively mitigates the harmful effects of HFFD-induced NAFLD compared to crude naringenin. Using a straightforward experimental setup, we utilize the bioactive flavonoid naringenin (NAR) as the reducing agent to synthesize naringenin-reduced graphene oxide nanosheets (Nar-RGO). Naringenin loading on graphene oxide was validated using electroscopic methods (SEM and TEM) and zeta potential measurements. Utilization of reduced graphene oxide for naringenin encapsulation resulted in a significant improvement in hepatic steatosis, insulin resistance, oxidative stress, and signs of inflammation in HFFD-induced NAFLD compared to crude naringenin. This study demonstrates that Nar-RGO exhibits significantly greater efficacy compared to free naringenin. Therefore, it can be used as a promising medicine in counteracting high-fat-fructose diet (HFFD)-induced NAFLD.

Dynamic changes and correlation analysis of microorganisms and flavonoids/ amino acids during white tea storage

White tea stored for various times have different flavors. However, the mechanism of flavor conversion remains elusive. Flavonoids and amino acids are two typical flavor components in tea. Herein, the contents of 46 flavonoids and 40 amino acids were measured in white tea (Shoumei) stored for 1, 3, 5 and 7 years, respectively. L-tryptophan, L-ornithine and L-theanine contribute to the refreshing taste of Shoumei 1 and 3. Quercetin, rutin and hesperidin contribute to aging charm and grain aroma of Shoumei 5 and 7. 306 bacterial OTUs and 268 fungal OTUs core microbiota existed in all samples. Interestingly, white teas contained higher richness of fungi than bacteria. The correlation analysis showed that the cooperation with bacteria and fungi may result in the flavonoids and amino acids composition changes in white teas during storage. Overall, this study provides new insights into flavor conversion of white tea during storage.

Acacetin, a Natural Flavone with Potential in Improving Liver Disease Based on Its Anti-Inflammation, Anti-Cancer, Anti-Infection and Other Effects

Liver disease is a global public problem, and the cost of its therapy is a large financial burden to governments. It is well known that drug therapy plays a critical role in the treatment of liver disease. However, present drugs are far from meeting clinical needs. Lots of efforts have been made to find novel agents to treat liver disease in the past several decades. Acacetin is a dihydroxy and monomethoxy flavone, named 5,7-dihydroxy-4'-methoxyflavone, which can be found in diverse plants. It has been reported that acacetin exhibits multiple pharmacological activities, including anti-cancer, anti-inflammation, anti-virus, anti-obesity, and anti-oxidation. These studies indicate the therapeutic potential of acacetin in liver disease. This review discussed the comprehensive information on the pathogenesis of liver disease (cirrhosis, viral hepatitis, drug-induced liver injury, and hepatocellular carcinoma), then introduced the biological source, structural features, and pharmacological properties of acacetin, and the possible application in preventing liver disease along with the pharmacokinetic and toxicity of acacetin, and future research directions. We systemically summarized the latest research progress on the potential therapeutic effect of acacetin on liver disease and existing problems. Based on the present published information, the natural flavone acacetin is an anticipated candidate agent for the treatment of liver disease.

Unveiling the Molecular Mechanisms of Browning in Camellia hainanica Callus through Transcriptomic and Metabolomic Analysis

Camellia hainanica is one of the camellia plants distributed in tropical regions, and its regeneration system and genetic transformation are affected by callus browning. However, the underlying mechanism of Camellia hainanica callus browning formation remains largely unknown. To investigate the metabolic basis and molecular mechanism of the callus browning of Camellia hainanica, histological staining, high-throughput metabolomics, and transcriptomic assays were performed on calli with different browning degrees (T1, T2, and T3). The results of histological staining revealed that the brown callus cells had obvious lignification and accumulation of polyphenols. Widely targeted metabolomics revealed 1190 differentially accumulated metabolites (DAMs), with 53 DAMs annotated as phenylpropanoids and flavonoids. Comparative transcriptomics revealed differentially expressed genes (DEGs) of the T2 vs. T1 associated with the biosynthesis and regulation of flavonoids and transcription factors in Camellia hainanica. Among them, forty-four enzyme genes associated with flavonoid biosynthesis were identified, including phenylalaninase (PAL), 4-coumaroyl CoA ligase (4CL), naringenin via flavanone 3-hydroxylase (F3H), flavonol synthase (FLS), Chalcone synthase (CHS), Chalcone isomerase (CHI), hydroxycinnamoyl-CoA shikimate transferase (HCT), Dihydroflavonol reductase (DFR), anthocyanin reductase (LAR), anthocyanin synthetase (ANS), and anthocyanin reductase (ANR). Related transcription factors R2R3-MYB, basic helix-loop-helix (bHLH), and WRKY genes also presented different expression patterns in T2 vs. T1. These results indicate that the browning of calli in Camellia hainanica is regulated at both the transcriptional and metabolic levels. The oxidation of flavonoids and the regulation of related structural genes and transcription factors are crucial decisive factors. This study preliminarily revealed the molecular mechanism of the browning of the callus of Camellia hainanensis, and the results can provide a reference for the anti-browning culture of Camellia hainanica callus.

Pharmacological Potential and Electrochemical Characteristics of Typha angustifolia Pollen

Typha angustifolia L. (TA) pollen has been utilized as a traditional Chinese medicine for treating various internal and external traumas. Moreover, bioactive compounds possess diverse pharmacological activities. This study aims to evaluate the antiviral properties of TA based on its ability to generate bioenergy, capable of inhibiting viruses. TA pollens were extracted using water and ethanol solvents. These extracts were utilized to identify the phytochemical contents and correlate with the antioxidant activity via 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. HPLC analysis was conducted to identify its electron-shuttling compositions. The bioenergy-generating characteristics were determined via microbial fuel cells. The water extract (TA-W) showed higher antioxidant activity due to a higher phenolic and flavonoid content compared to the ethanol extract (TA-E). Quercetin-3-O-(2G-α-L-rhamnosyl)-rutinoside, quercetin-3-O-neohesperidoside, and quercetin are the electron shuttles (ES) identified out of the 11 compounds. TA obtained a 1.39 ± 0.10 amplification factor of power generation that indicates potential bioenergy-generating and associated antiviral characteristic properties. The findings may provide a foundation for developing antiviral medications specifically designed to target virus-related diseases, while minimizing the risk of drug toxicity and reducing the costs of drug development.

Transcription factor PdMYB118 in poplar regulates lignin deposition and xylem differentiation in addition to anthocyanin synthesis through suppressing the expression of PagKNAT2/6b gene

R2R3-MYB transcription factors function as the master regulators of the phenylpropanoid pathway in which both lignin and anthocyanin are produced. In poplar, R2R3-MYB transcription factor PdMYB118 positively regulates anthocyanin production to change leaf color. However, the molecular mechanism by which it controls different branches of the phenylpropanoid pathway still remains poorly understood. Here, we reported that in addition to anthocyanin synthesis, lignin deposition and xylem differentiation were regulated by PdMYB118 through inhibiting PagKNAT2/6b gene expression. The transgenic poplar plants overexpressing PdMYB118 accumulated more xylem, lignin and anthocyanin. Transcriptome and reverse transcription quantitative PCR analyses revealed that the expression of PagKNAT2/6b gene which inhibited lignin deposition and xylem differentiation was significantly down-regulated in transgenic poplar plants. Subsequent dual-luciferase reporter and yeast-one-hybrid assays demonstrated that PdMYB118 directly inhibited the transcription of PagKNAT2/6b by binding to the AC elements in its promoter region. Further experiments with transgenic poplar plants overexpressing PagKNAT2/6b demonstrated that overexpression of PagKNAT2/6b in the PdMYB118 overexpression background rescued lignin accumulation and xylem width to the same level of wild type plants. The findings in this work suggest that PdMYB118 is involved in the lignin deposition and xylem differentiation via modulating the expression of PagKNAT2/6b, and the PdMYB118- PagKNAT2/6b model can be used for the genetic breeding of new woody tree with high lignin production.

Variation in the Phenolic Profile and Antioxidant, Antihyperglycemic, and Anti-Inflammatory Activity in Leaves of Cotoneaster zabelii during Growing Season

Cotoneaster zabelii is a medicinal plant that is beneficial due to its polyphenol-rich leaves. In the course of optimizing the harvest time for C. zabelii cultivated in Poland, the leaf samples were collected monthly during the annual plant vegetation season, and the hydromethanolic leaf extracts were evaluated for their phenolic composition and model biological activities, including antioxidant, antihyperglycemic, and anti-inflammatory effects in vitro. The phenolic profiles were analyzed using UHPLC-PDA-ESI-MS3, HPLC-PDA, and spectrophotometric methods (total phenolic content, TPC) to understand their seasonal variability and its correlation with bioactive properties. The identified phenolic compounds included caffeic acid derivatives, flavan-3-ols (especially (-)-epicatechin and procyanidins B-type), and flavonoids like quercetin mono- and diglycosides. Leaves harvested in July and October contained the highest polyphenolic levels and demonstrated significant antioxidant activity in most tests. The leaves harvested in July, September, and October showed optimal anti-inflammatory effects, whereas the highest antihyperglycemic activity was observed in the leaves collected from June to July. Regarding polyphenolic levels and bioactivity, the summer and autumn months appear to be the most advantageous for harvesting leaf material of optimal quality for phytotherapy.

Dynamics of flavonoid metabolites in coconut water based on metabolomics perspective

Coconut meat and coconut water have garnered significant attention for their richness in healthful flavonoids. However, the dynamics of flavonoid metabolites in coconut water during different developmental stages remain poorly understood. This study employed the metabolomics approach using liquid chromatography-tandem mass spectrometry (LC-MS/MS) to investigate the changes in flavonoid metabolite profiles in coconut water from two varieties, 'Wenye No.5'(W5) and Hainan local coconut (CK), across six developmental stages. The results showed that a total of 123 flavonoid metabolites including chalcones, dihydroflavonoids, dihydroflavonols, flavonoids, flavonols, flavonoid carboglycosides, and flavanols were identified in the coconut water as compared to the control. The total flavonoid content in both types of coconut water exhibited a decreasing trend with developmental progression, but the total flavonoid content in CK was significantly higher than that in W5. The number of flavonoid metabolites that differed significantly between the W5 and CK groups at different developmental stages were 74, 74, 60, 92, 40 and 54, respectively. KEGG pathway analysis revealed 38 differential metabolites involved in key pathways for flavonoid biosynthesis and secondary metabolite biosynthesis. This study provides new insights into the dynamics of flavonoid metabolites in coconut water and highlights the potential for selecting and breeding high-quality coconuts with enhanced flavonoid content. The findings have implications for the development of coconut-based products with improved nutritional and functional properties.

Inhibitory Effects of Fruit Powders on the Formation of Polycyclic Aromatic Hydrocarbons in Charcoal-Grilled Pork

Polycyclic aromatic hydrocarbons (PAHs), carcinogenic substances primarily formed through pyrolysis and oxidation of fat at high cooking temperatures, are commonly found at high levels in grilled meats. Reducing PAHs formation by incorporating natural antioxidants, such as through marination, has been demonstrated to be effective. However, the inhibitory effect of fresh phenolic-rich fruit powders on PAHs formation in charcoal-grilled meats remains unknown. To clarify the application of the fruit powders, 15 experimental groups were conducted. All pretreatment techniques (spraying, marinating, and mixing) were applied across all four freeze-dried fruit powders (lemon, guava, papaya, and mango). Each method was systematically tested with each fruit powder to evaluate its effect on inhibiting the formation of the four PAHs (BaA, CHR, BbF, and BaP) in charcoal-grilled pork belly and loin. Firstly, guava powder exhibited the highest phenolic content and antioxidant activity compared to the lemon, papaya, and mango powders (p < 0.05), among which the main phenolic compounds were ellagic acid, quercetin, and epigallocatechin gallate (EGCG). Further, marination of pork belly with guava powder exhibited the highest inhibition rate of PAHs (94.8%), followed by lemon (91.1%), papaya (89.8%), and mango (89.0%), with a statistically significant difference at p < 0.05. The reduction in estimated daily intake (EDI) and the increase in the margin of exposure (MOE) indicate that consuming grilled meat treated with these fruit powders poses no safety concerns and may potentially reduce health risks. Finally, the sensory evaluation showed that marinating with guava powder did not perceptibly affect the sensory attributes of the meat. Overall, this study provides a potent strategy for inhibiting the formation of PAHs in meat during charcoal grilling by incorporating fruit powder while preserving sensory qualities.

Molecular Mechanism of 5,6-Dihydroxyflavone in Suppressing LPS-Induced Inflammation and Oxidative Stress

5,6-dihydroxyflavone (5,6-DHF), a flavonoid that possesses potential anti-inflammatory and antioxidant activities owing to its special catechol motif on the A ring. However, its function and mechanism of action against inflammation and cellular oxidative stress have not been elucidated. In the current study, 5,6-DHF was observed inhibiting lipopolysaccharide (LPS)-induced nitric oxide (NO) and cytoplasmic reactive oxygen species (ROS) production with the IC50 of 11.55 ± 0.64 μM and 0.8310 ± 0.633 μM in murine macrophages, respectively. Meanwhile, 5,6-DHF suppressed the overexpression of pro-inflammatory mediators such as proteins and cytokines and eradicated the accumulation of mitochondrial ROS (mtROS). The blockage of the activation of cell surface toll-like receptor 4 (TLR4), impediment of the phosphorylation of c-Jun N-terminal kinase (JNK) and p38 from the mitogen-activated protein kinases (MAPK) pathway, Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3) from the JAK-STAT pathway, and p65 from nuclear factor-κB (NF-κB) pathways were involved in the process of 5,6-DHF suppressing inflammation. Furthermore, 5,6-DHF acted as a cellular ROS scavenger and heme-oxygenase 1 (HO-1) inducer in relieving cellular oxidative stress. Importantly, 5,6-DHF exerted more potent anti-inflammatory activity than its close structural relatives, such as baicalein and chrysin. Overall, our findings pave the road for further research on 5,6-DHF in animal models.

Antitumoral Activity of Cecropia Pachystachya Leaves Extract in Vitro and in Vivo Model of Rat Glioma: Brain and Blood Effects

The aim of this study was to investigate the antiglioma effect of Cecropia pachystachya Trécul (CEC) leaves extract against C6 and U87 glioblastoma (GB) cells and in a rat preclinical GB model. The CEC extract reduced in vitro cell viability and biomass. In vivo, the extract decreased the tumor volume approximately 62%, without inducing systemic toxicity. The deficit in locomotion and memory and an anxiolytic-like behaviors induced in the GB model were minimized by CEC. The extract decreased the levels of reactive oxygen species, nitrites and thiobarbituric acid reactive substances and increased the activity of antioxidant enzymes in platelets, sera and brains of GB animals. The activity of NTPDases, 5'-nucleotidase and adenosine deaminase (ADA) was evaluated in lymphocytes, platelets and serum. In platelets, ATP and AMP hydrolysis was reduced and hydrolysis of ADP and the activity of ADA were increased in the control, while in CEC-treated animals no alteration in the hydrolysis of ADP was detected. In serum, the reduction in ATP hydrolysis was reversed by CEC. In lymphocytes, the increase in the hydrolysis of ATP, ADP and in the activity of ADA observed in GB model was altered by CEC administration. The observed increase in IL-6 and decrease in IL-10 levels in the serum of GB animals was reversed by CEC. These results demonstrate that CEC extract is a potential complementary treatment to GB, decreasing the tumor size, while modulating aspects of redox and purinergic systems.

A comprehensive review on recent xanthine oxidase inhibitors of dietary based bioactive substances for the treatment of hyperuricemia and gout: Molecular mechanisms and perspective

Hyperuricemia (HUA) has attained a considerable global health concern, related to the development of other metabolic syndromes. Xanthine oxidase (XO), the main enzyme that catalyzes xanthine and hypoxanthine into uric acid (UA), is a key target for drug development against HUA and gout. Available XO inhibitors are effective, but they come with side effects. Recent, research has identified new XO inhibitors from dietary sources such as flavonoids, phenolic acids, stilbenes, alkaloids, polysaccharides, and polypeptides, effectively reducing UA levels. Structural activity studies revealed that -OH groups and their substitutions on the benzene ring of flavonoids, polyphenols, and stilbenes, cyclic rings in alkaloids, and the helical structure of polysaccharides are crucial for XO inhibition. Polypeptide molecular weight, amino acid sequence, hydrophobicity, and binding mode, also play a significant role in XO inhibition. Molecular docking studies show these bioactive components prevent UA formation by interacting with XO substrates via hydrophobic, hydrogen bonds, and π-π interactions. This review explores the potential bioactive substances from dietary resources with XO inhibitory, and UA lowering potentials detailing the molecular mechanisms involved. It also discusses strategies for designing XO inhibitors and assisting pharmaceutical companies in developing safe and effective treatments for HUA and gout.

Antioxidant Mechanism, Spectroscopic and Pharmacological Properties of Four Flavonoids: DFT, Docking and Molecular Dynamics

Myricetin (1), Quercetin (2), Kaempferol (3) and Kaempferide (4) were flavonoids with phenolic hydroxyl groups. The antioxidant and pharmacological mechanisms of them were investigated in detail. The lowest hydroxyl dissociation enthalpies of 1, 2, 3 and 4 were calculated by DFT, respectively. The hydroxyl dissociation enthalpies of the four flavonoids at the O2 site are the highest. By analyzing the intramolecular hydrogen bonds and HOMO-LUMO orbitals of the four flavonoids, the reasons for their divergence of hydroxyl dissociation enthalpies and antioxidant mechanisms were further investigated. The UV-vis and IR spectra of four flavonoids were compared. The interactions about electrostatic attraction, p-π conjugation and hydrogen bond combined the flavonoid with the target protein closely. The root mean square deviation of peroxisome proliferator-activated receptor γ combined with 1, 2 and 3 increased, while that of PPARγ combined with 4 decreased.

A comprehensive view on the fisetin impact on colorectal cancer in animal models: Focusing on cellular and molecular mechanisms

Flavonoids, including fisetin, have been linked to a reduced risk of colorectal cancer (CRC) and have potential therapeutic applications for the condition. Fisetin, a natural flavonoid found in various fruits and vegetables, has shown promise in managing CRC due to its diverse biological activities. It has been found to influence key cell signaling pathways related to inflammation, angiogenesis, apoptosis, and transcription factors. The results of this study demonstrate that fisetin induces colon cancer cell apoptosis through multiple mechanisms. It impacts the p53 pathway, leading to increased levels of p53 and decreased levels of murine double minute 2, contributing to apoptosis induction. Fisetin also triggers the release of important components in the apoptotic process, such as second mitochondria-derived activator of caspase/direct inhibitor of apoptosis-binding protein with low pI and cytochrome c. Furthermore, fisetin inhibits the cyclooxygenase-2 and wingless-related integration site (Wnt)/epidermal growth factor receptor/nuclear factor kappa B signaling pathways, reducing Wnt target gene expression and hindering colony formation. It achieves this by regulating the activities of cyclin-dependent kinase 2 and cyclin-dependent kinase 4, reducing retinoblastoma protein phosphorylation, decreasing cyclin E levels, and increasing p21 levels, ultimately influencing E2 promoter binding factor 1 and cell division cycle 2 (CDC2) protein levels. Additionally, fisetin exhibits various effects on CRC cells, including inhibiting the phosphorylation of Y-box binding protein 1 and ribosomal S6 kinase, promoting the phosphorylation of extracellular signal-regulated kinase 1/2, and disrupting the repair process of DNA double-strand breaks. Moreover, fisetin serves as an adjunct therapy for the prevention and treatment of phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit α (PIK3CA)-mutant CRC, resulting in a reduction in phosphatidylinositol-3 kinase (PI3K) expression, Ak strain transforming phosphorylation, mTOR activity, and downstream target proteins in CRC cells with a PIK3CA mutation. These findings highlight the multifaceted potential of fisetin in managing CRC and position it as a promising candidate for future therapy development.

Using terahertz spectroscopy to quantify bioactive flavonoids in Moxa Wool as predictor of rheumatoid arthritis treatment outcomes

BACKGROUND

Moxibustion, a traditional Chinese medicine practice, employs Moxa Wool, derived from Artemisia argyi. Flavonoids, the key pharmacological constituents in Moxa Wool, are known for their anti-inflammatory and analgesic properties. The purity of Moxa Wool, particularly its flavonoid content, directly influences the efficacy of moxibustion treatments. However, quantifying these bioactive flavonoids accurately and non-destructively has been a challenge.

PURPOSE

This study introduces terahertz spectroscopy as a non-destructive optical detection method for qualitative detection and quantitative analysis of flavonoids in Moxa Wool. By establishing a mathematical model between spectral signals and clinical efficacy, a reliable correlation between flavonoid concentration and the therapeutic effect of moxibustion can be established, providing a potential predictive model for the treatment outcomes of rheumatoid arthritis.

STUDY DESIGN

We adopted terahertz spectroscopy technology and combined it with terahertz metamaterial biosensors to achieve rapid, efficient, and non-destructive testing of the quality of Moxa Wool. This method reduces the detection time from hours to minutes while lowering the sample detection limit, overcoming the limitations of traditional detection methods in pharmacological research.

METHODS

Through terahertz metamaterial biosensors, rapid detection of the purity of Moxa Wool has been achieved. A combination of molecular simulation and terahertz spectroscopy was used to quantitatively analyze the flavonoid content in different purities of Moxa Wool. To ensure accuracy, the quantitative results of flavonoids obtained by terahertz spectroscopy were validated using high-performance liquid chromatography (HPLC). In addition, moxibustion treatment was performed on rats with rheumatoid arthritis using Moxa Wool, and medical indicator information was recorded. A mathematical analysis model was established to evaluate the correlation between flavonoid content and analgesic and anti-inflammatory effects.

RESULTS

Terahertz spectroscopy analysis shows that there is a direct correlation between the flavonoid content in moxibustion and the absorption peak intensity. The maximum R2 in the model analysis is 0.98, indicating a high accuracy in predicting the purity of Moxa Wool. These results were also validated by HPLC. In a rat model, the purity of 30:1 Moxa Wool samples showed a 50 % decrease in TNF-α, IL-1β, and IL-6 levels during treatment compared to low-purity samples, significantly reducing inflammation markers and pain symptoms. Meanwhile, The PLS prediction model established a correlation between terahertz-detected flavonoid levels and treatment outcomes (PWL and IL-1β). The maximum R2 in the model is 0.91, indicating a high correlation between flavonoid levels and the anti-inflammatory and analgesic effects of moxibustion treatment.

CONCLUSION

This study not only demonstrates the effectiveness of terahertz spectroscopy in the pharmacological quantification of bioactive compounds but also establishes a novel predictive model for the efficacy of moxibustion in rheumatoid arthritis treatment. It underscores the potential of integrating traditional medicine insights with advanced technology to enhance therapeutic strategies in pharmacology.

HPLC/ESI-QTOF-MS/MS based untargeted metabolomics authentication of Taxus × media six tissues

INTRODUCTION

Taxus media (Taxus × media Rehder) is renowned for its high paclitaxel content, serving as a major source for industrial paclitaxel production. In addition to paclitaxel, T. media contains a diverse range of metabolites, including flavonoids, alkaloids, and terpenoids, which have been shown to possess antioxidant, antibacterial, anti-inflammatory, and immunomodulatory effects. However, these compounds have not been thoroughly studied as key metabolites in T. media.

OBJECTIVE

The untargeted metabolomics analysis of six T. media tissues provides new insights into the development and utilization of T. media metabolites.

METHOD

The extracts from six tissues of T. media were analyzed and subjected to analysis using high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS/MS) and chemometric techniques.

RESULTS

Using a reliable HPLC-Q-TOF-MS/MS method, we identified 312 compounds in six T. media tissues, including 214 previously unreported in T. media. To identify characteristic compounds across different tissues, 34 metabolites were further screened. KEGG metabolic pathway analysis revealed that these compounds primarily occur in the metabolic pathways of terpene glycosides, flavans, and O-methylated flavonoids.

CONCLUSION

This study initially utilized an HPLC-QTOF-MS/MS-based metabolomics approach to assess the metabolites in different tissues of T. media, providing a basis for their utilization and management.

The potential of flavonoids in hepatic fibrosis: A comprehensive review

BACKGROUND

Hepatic fibrosis is a pathophysiological process of extracellular matrix abnormal deposition induced by multiple pathogenic factors. Currently, there is still a lack of effective and non-toxic drugs for treating fibrosis in clinic. Flavonoids are polyphenolic compounds synthesized in plants and modern pharmacological studies confirmed flavonoids exhibit potent hepatoprotective effect.

PURPOSE

Summarize literature to elaborate the mechanism of HF and evaluate the potential of flavonoids in HF, aiming to provide a new perspective for future research.

METHODS

The literatures about hepatic fibrosis and flavonoids are collected via a series of scientific search engines including Google Scholar, Elsevier, PubMed, CNKI, WanFang, SciFinder and Web of Science database. The key words are "flavonoids", "hepatic fibrosis", "pharmacokinetic", "toxicity", "pathogenesis" "traditional Chinese medicine" and "mechanism" as well as combination application.

RESULTS

Phytochemical and pharmacological studies revealed that about 86 natural flavonoids extracted from Chinese herbal medicines possess significantly anti-fibrosis effect and the mechanisms maybe through anti-inflammatory, antioxidant, inhibiting hepatic stellate cells activation and clearing activated hepatic stellate cells.

CONCLUSIONS

This review summarizes the flavonoids which are effective in HF and the mechanisms in vivo and in vitro. However, fewer studies are focused on the pharmacokinetics of flavonoids in HF model and most studies are limited to preclinical studies, therefore there is no reliable data from clinical trials for the development of new drugs. Further in-depth research related it can be conducted to improve the bioavailability of flavonoids and serve the development of new drugs.

Antidiabetic and Antigout Properties of the Ultrasound-Assisted Extraction of Total Biflavonoids from Selaginella doederleinii Revealed by In Vitro and In Silico Studies

In this study, the extraction, purification and metabolic enzyme inhibition potential of Selaginella doederleinii were investigated. In order to extract the total biflavonoids from S. doederleinii (SDTBs), the optimum extraction process was obtained by optimizing the ultrasonic extraction parameters using response-surface methodology. This resulted in a total biflavonoid content of 22.26 ± 0.35 mg/g. Purification of the S. doederleinii extract was carried out using octadecylsilane (ODS), and the transfer rate of the SDTBs was 82.12 ± 3.48% under the optimum purification conditions. We determined the effect of the SDTBs on α-glucosidase (AG), α-amylase and xanthine oxidase (XOD) and found that the SDTBs had an extremely potent inhibitory effect on AG, with an IC50 value of 57.46 μg/mL, which was much lower than that of the positive control. Meanwhile, they also showed significant inhibition of XOD and α-amylase, with IC50 values of 289.67 μg/mL and 50.85 μg/mL, respectively. In addition, molecular docking studies were carried out to understand the nature of the action of the biflavonoids on AG and XOD. The results showed that robustaflavone had the lowest binding energy to AG (-11.33 kcal/mol) and XOD (-10.21 kcal/mol), while, on the other hand, amentoflavone showed a good binding affinity to AG (-10.40 kcal/mol) and XOD (-9.962 kcal/mol). Moreover, molecular dynamics simulations verified the above results.

Muti-omics revealed the mechanisms of MT-conferred tolerance of Elymus nutans Griseb. to low temperature at XiZang

BACKGROUND

Low temperature seriously limited the development of grass and crops in plateau. Thus, it is urgent to develop an effective strategy for improving the plant cold tolerance and elucidate the underlying mechanisms.

RESULTS

We found that MT alleviated the effects of cold stress on suppressing ENG growth, then improved cold tolerance of ENG. Integration of transcriptome and metabolome profiles showed that both cold exposure (TW) and MT reprogrammed the transcription pattern of galactose and flavonoids biosynthesis, leading to changes in compositions of soluble sugar and flavonoids in ENG. Additionally, TW inhibited the photosynthesis, and destroyed the antioxidant system of ENG, leading to accumulation of oxidant radicals represented by MDA. By contrast, MT promoted activities of antioxidant enzymes and flavonoid accumulation in ENG under cold condition, then reduced the MDA content and maintained normal expression of photosynthesis-related genes in ENG even under TW. Importantly, MT mainly enhanced cold tolerance of ENG via activating zeatin synthesis to regulate flavonoid biosynthesis in vivo. Typically, WRKY11 was identified to regulate MT-associated zeatin synthesis in ENG via directly binding on zeatin3 promoter.

CONCLUSIONS

MT could enhance ENG tolerance to cold stress via strengthening antioxidant system and especially zeatin synthesis to promote accumulation of flavonoids in ENG. Thus, our research gain insight into the global mechanisms of MT in promoting cold tolerance of ENG, then provided guidance for protecting plant from cold stress in plateau.

3'-8″- Biflavones: A Review of Their Structural Diversity, Natural Occurrence, Role in Plants, Extraction and Identification

Dimeric forms of flavonoids, known as biflavonoids, are much less studied compared to monomeric forms. It is estimated that nearly 600 different natural biflavonoids have been described to date, containing various subtypes that can be subdivided according to the position of their combinations and the nature of the subunits. The group in which two monomers are linked by a 3'-8″-C atom includes the first isolated biflavonoid ginkgetin, derivatives of amentoflavone, and several other compounds. 3'-8″-biflavones recently attracted much attention as potential molecules with biological activity such as antiviral and antimicrobial activity and as effective molecules for the treatment of neurodegenerative and metabolic diseases and in cancer therapies. With the growing interest in them as pharmacologically active molecules, there is also increasing interest in finding new natural sources of 3'-8″-biflavones and optimizing methods for their extraction and identification. Herein, we have summarized the available data on the structural diversity, natural occurrence, role in plants, extraction, and identification of 3'-8″-biflavones.

Insights into Tissue-Specific Specialized Metabolism in Wampee (Clausena lansium (Lour.) Skeels) Varieties

Wampee (Clausena lansium (Lour.) Skeels) has natural bioactive components with diverse health benefits, but its detailed metabolism and tissue distribution are not fully understood. Here, widely targeted metabolomics analysis methods were employed to analyze the wampee fruit (peel, pulp, and seed) of 17 different varieties. A total of 1286 metabolites were annotated, including lipids, flavonoids, polyphenols, carbazole alkaloids, coumarins, and organic acids, among others. The quantitative analysis and matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) analysis indicated remarkable variations in metabolite categories and content in the peel, pulp, and seed of wampee fruit. Additionally, the difference analysis found that the metabolic components of peel contributed dominantly to the differences among varieties, and 7 potential biomarkers were identified. In this study, a comprehensive metabolome landscape of wampee fruit was established, which provided important information for the isolation and identification of functional components, food industry application, and nutritional improvement breeding.

Nuclear factor erythroid 2-related factor-mediated signaling alleviates ferroptosis during cerebral ischemia-reperfusion injury

Cardiac arrest (CA) is a significant challenge for emergency physicians worldwide and leads to increased morbidity and mortality rates. The poor prognosis of CA primarily stems from the complexity and irreversibility of cerebral ischemia-reperfusion injury (CIRI). Ferroptosis, a form of programmed cell death characterized by iron overload and lipid peroxidation, plays a crucial role in the progression and treatment of CIRI. In this review, we highlight the mechanisms of ferroptosis within the context of CIRI, focusing on its role as a key contributor to neuronal damage and dysfunction post-CA. We explore the crucial involvement of the nuclear factor erythroid 2-related factor (Nrf2)-mediated signaling pathway in modulating ferroptosis-associated processes during CIRI. Through comprehensive analysis of the regulatory role of Nrf2 in the cellular responses to oxidative stress, we highlight its potential as a therapeutic target for mitigating ferroptotic cell death and improving the neurological prognosis of patients experiencing CA. Furthermore, we discuss interventions targeting the Kelch-like ECH-associated protein 1/Nrf2/antioxidant response element pathway, including the use of traditional Chinese medicine and Western medicine, which demonstrate potential for attenuating ferroptosis and preserving neuronal function in CIRI. Owing to the limitations in the safety, specificity, and effectiveness of Nrf2-targeted drugs, as well as the technical difficulties and ethical constraints in obtaining the results related to the brain pathological examination of patients, most of the studies focusing on Nrf2-related regulation of ferroptosis in CIRI are still in the basic research stage. Overall, this review aims to provide a comprehensive understanding of the mechanisms underlying ferroptosis in CIRI, offering insights into novel therapeutics aimed at enhancing the clinical outcomes of patients with CA.

The effects of plant flavones on the membrane boundary potential and lipid packing stress

Here we have revealed the effects of different plant flavones on the physicochemical properties of model lipid membranes. We have demonstrated that baicalein increases the boundary potential of membranes composed of phosphatidylcholine, while wogonin does not affect it. Other flavones tested reduce membrane boundary potential, with this ability increasing among scutellarein, chrysin, apigenin, morin, fisetin, and luteolin. Molecular dynamics simulations demonstrate connection of alteration in boundary potential with the preferential orientation of intrinsic flavone dipole moments in membranes. We have also shown that flavones reduce the melting point of phosphatidylcholine, and this ability increases in the series of luteolin, morin, wogonin, scutellarein, apigenin, baicalein, chrysin, and fisetin. The introduction of baicalein, chrysin and fisetin also leads to a significant decrease in the sharpness of the lipid phase transition. We have hypothesized that the localization of flavones in the glycerol backbone or in the C1-C8 methylene region of lipid hydrocarbon chains leads to an increase in the area per lipid and, as a consequence, to an expansion of the lipid melting peak. Replacement of neutral phosphatidylcholine with negatively charged phosphatidylserine affects the membrane-modifying activity of flavones which given the externalization of phosphatidylserine on the surface of cancer cells may be crucial in the flavone anticancer effects.

Comprehensive understanding of impacts of steam explosion on facilitated extraction and transformation of flavonoids from Astragali Radix

Recalcitrant structure of cell walls restricts the extraction of bioactive components from edible plants. In this study, the impacts of steam explosion (SE) on the release and transformation of flavonoids in Astragali Radix (AR) were evaluated. Results revealed that SE destroyed the compact structure of cell walls. Furthermore, the porous network was reformed due to the degradation of hemicelluloses and water-soluble components. The maximum extraction contents of ethanol-soluble and water-soluble flavonoids of 6.34 and 1.48 mg/g were obtained from the pretreated AR (1.5 MPa, 5 min), which were 5.22 and 2.88 times higher than those obtained from the untreated AR, respectively. SE not only released bound flavonoids from cell walls by cleaving glycoside or ester bonds, but also transformed some flavonoid glycosides into aglycones through deglycosylation. In conclusion, SE can reduce mass transfer hindrance and facilitate flavonoid transformation, thus providing a green and facile processing method for traditional edible plants.

Comparative Analysis of Citrus Species' Flavonoid Metabolism, Gene Expression Profiling, and Their Antioxidant Capacity under Drought Stress

Citrus species are widely cultivated across the globe and frequently encounter drought stress during their growth and development phases. Previous research has indicated that citrus species synthesize flavonoids as a response mechanism to drought stress. This study aimed to comprehensively quantify and analyze the presence of 85 distinct flavonoids in the leaf and root tissues of lemon (drought susceptible) and sour orange (drought tolerant). In drought-stressed sour orange roots, flavonoids, such as isosakuranin, mangiferin, trilobatin, liquiritigenin, avicularin, silibinin, and glabridin, were more elevated than control sour orange roots and drought-stressed lemon roots. Additionally, hydroxysafflor yellow A, cynaroside, tiliroside, and apigenin 7-glucoside were increased in drought-stressed sour orange leaves compared to drought-stressed lemon leaves. Under drought stress, flavonoids such as (-)-epigallocatechin, silibinin, benzylideneacetophenone, trilobatin, isorhamnetin, 3,7,4'-trihydroxyflavone, and liquiritigenin were significantly increased, by 3.01-, 3.01-, 2.59-, 2.43-, 2.07-, 2.05-, and 2.01-fold, in sour orange roots compared to control sour orange roots. Moreover, the total flavonoid content and antioxidant capacity were significantly increased in drought-stressed sour orange leaves and root tissues compared to drought-stressed lemon leaves and root tissues. The expression levels of genes involved in flavonoid biosynthesis were highly expressed in sour orange leaves and roots, compared to lemon leaves and root tissues, post-drought stress. These findings indicate that lemons fail to synthesize protective flavonoids under drought conditions, whereas sour orange leaves and root tissues enhance flavonoid synthesis, with higher antioxidant activities to mitigate the adverse effects of reactive oxygen species generated during drought stress.

Biosynthesis and Extraction of Chlorophyll, Carotenoids, Anthocyanins, and Betalaine In Vivo and In Vitro

As natural bioactive compounds, plant pigments play crucial roles not only in plant phenotype, growth, development, and adaptation to stress but also hold unique value in biotechnology, healthcare, and industrial applications. There is growing interest in the biosynthesis and acquisition of plant pigments. Thus, this paper explores emerging extraction methods of natural pigments and elucidates the biosynthesis pathways of four key plant pigments, chlorophylls, carotenoids, anthocyanins, and betalaine in vivo and in vitro. We comprehensively discuss the application of solvent, supercritical fluid [extraction], ultrasonic, and microwave-assisted extraction techniques, as well as introducing key enzymes, precursors, and synthetic pathways involved in pigment synthesis. δ-Aminolevulinic acid represents a pivotal initiating enzyme for chlorophyll synthesis, whereas isopentenylpyrophosphate, (IPP) and dimethylallyl pyrophosphate, (DMAPP) are closely associated with carotenoid biosynthesis. Phenylalanine and tyrosine are critical substances for anthocyanin and betalaine synthesis, respectively. Hence, crucial genes such as chlI, crtB, PGT8, CYP76AD1, and BvDODA can be employed for heterologous biosynthesis in vitro to meet the demand for increased plant pigment amount. As a pivotal determinant of plant coloration, an in-depth exploration into the high-quality acquisition of plant pigments can provide a basis for developing superior pigments and offer new insights into increasing pigment yield.

Transcriptomic and coexpression network analyses revealed the regulatory mechanism of Cydia pomonella infestation on the synthesis of phytohormones in walnut husks

The codling moth (Cydia pomonella) has a major effect on the quality and yield of walnut fruit. Plant defences respond to insect infestation by activating hormonal signalling and the flavonoid biosynthetic pathway. However, little is known about the role of walnut husk hormones and flavonoid biosynthesis in response to C. pomonella infestation. The phytohormone content assay revealed that the contents of salicylic acid (SA), abscisic acid (ABA), jasmonic acid (JA), jasmonic acid-isoleucine conjugate (JA-ILE), jasmonic acid-valine (JA-Val) and methyl jasmonate (MeJA) increased after feeding at different time points (0, 12, 24, 36, 48, and 72 h) of walnut husk. RNA-seq analysis of walnut husks following C. pomonella feeding revealed a temporal pattern in differentially expressed genes (DEGs), with the number increasing from 3,988 at 12 h to 5,929 at 72 h postfeeding compared with the control at 0 h postfeeding. Walnut husks exhibited significant upregulation of genes involved in various defence pathways, including flavonoid biosynthesis (PAL, CYP73A, 4CL, CHS, CHI, F3H, ANS, and LAR), SA (PAL), ABA (ZEP and ABA2), and JA (AOS, AOC, OPR, JAZ, and MYC2) pathways. Three gene coexpression networks that had a significant positive association with these hormonal changes were constructed based on the basis of weighted gene coexpression network analysis (WGCNA). We identified several hub transcription factors, including the turquoise module (AIL6, MYB4, PRE6, WRKY71, WRKY31, ERF003, and WRKY75), the green module (bHLH79, PCL1, APRR5, ABI5, and ILR3), and the magenta module (ERF27, bHLH35, bHLH18, TIFY5A, WRKY31, and MYB44). Taken together, these findings provide useful genetic resources for exploring the defence response mediated by phytohormones in walnut husks.

A comprehensive overview on antiviral effects of baicalein and its glucuronide derivative baicalin

Natural product-based antiviral candidates have received significant attention. However, there is a lack of sufficient research in the field of antivirals to effectively combat patterns of drug resistance. Baicalein and its glucuronide derivative baicalin are two main components extracted from Scutellaria baicalensis Georgi. They have proven to be effective against a broad range of viruses by directly killing virus particles, protecting infected cells, and targeting viral antigens on their surface, among other mechanisms. As natural products, they both possess the advantage of lower toxicity, enhanced therapeutic efficacy, and even antagonistic effects against drug-resistant viral strains. Baicalein and baicalin exhibit promising potential as potent pharmacophore scaffolds, demonstrating their antiviral properties. However, to date, no review on the antiviral effects of baicalein and baicalin has been published. This review summarizes the recent research progress on antiviral effects of baicalein and baicalin against various types of viruses both in vitro and in vivo with a focus on the dosages and underlying mechanisms. The aim is to provide a basis for the rational development and utilization of baicalein and baicalin, as well as to promote antiviral drug research. Please cite this article as: Liu XY, Xie W, Zhou HY, Zhang HQ, Jin YS. A comprehensive overview on antiviral effects of baicalein and its glucuronide derivative baicalin. J Integr Med. 2024; Epub ahead of print.