Major Flavonoid Research Articles

Bioactive compounds and antioxidant activity in various parts of Morus alba L. Cv. ichinose: a comparative analysis

Present investigation was undertaken to assess the composition of bioactive compounds within various parts of methanolic extracts from mulberry plants utilizing both High-Performance Liquid Chromatography (HPLC) and spectrophotometric methodologies. Furthermore, the antioxidant potential was evaluated through assays including 2,2-diphenyl-1-picrylhydrazyl (DPPH), Ferric Reducing Antioxidant Power (FRAP), β-carotene bleaching (BCBA), and Hydroxyl Radical Scavenging Activity (HRSA). This research incorporated the analysis of the fruit, root, shoot, and leaf of the mulberry (Morus alba L.) Cv. Ichinose. Findings from the investigation revealed that levels of total phenols (533.8 ± 15.6 mg/100 g) and flavonoids (232.3 ± 7.1 mg/100 g) were notably higher in fruit compared to root, while total ascorbic acid content (70.9 ± 3.1 mg/100 g) was significantly elevated in the leaf. The fruit exhibited a significantly higher concentration of total anthocyanins (142.5 ± 3.1 mg/100 g), whereas the leaf contained a substantial amount of total carotenoids (5.8 ± 0.3 mg/100 g). Predominant phenolic acids detected in mulberry included ferulic acid, m-coumaric acid, syringic acid, caffeic acid, chlorogenic acid, and gallic acid. Quercetin and isoquercetin were identified as the major flavonoids in mulberry fruits. In terms of anthocyanins, cyanidin-3-rutinoside (25.6 ± 2.3 mg/100 g) and cyanidin-3-glucoside (16.4 ± 2.1 mg/100 g) were the primary anthocyanins present in the fruit. The main carotenoid found in the leaf was beta-carotene, with levels reaching 2.1 ± 0.3 mg/100 g. Fruit displayed the highest antioxidant activity among all parts examined. Comparison of the EC50 values of fruit (EC50 = 174.2 ± 2.2 µg/mL), root (EC50 = 179.6 ± 2.3 µg/mL), and shoot (EC50 = 189.4 ± 2.1) suggested that these segments of the mulberry plant could potentially function as antioxidants and could exhibit a greater hydroxyl radical scavenging effect than standard antioxidants.

The inhibitory activity of Flos Sophorae Immaturus extract and its major flavonoid components on pancreatic lipase

Inhibition of pancreatic lipase (PL) is a strategy to prevent obesity. The inhibitory effects of Flos Sophorae Immaturus (FSI) extract and its main flavonoid components, rutin and quercetin, on PL were investigated. The contents of rutin and quercetin in FSI extract were 44.10 ± 1.33 % and 6.07 ± 1.62 %, respectively. The IC50 values of FSI extract, rutin and quercetin on PL were 322, 258 and 71 μg/mL, respectively. Rutin and quercetin inhibited PL in a reversible and noncompetitive manner. The combination of rutin and quercetin exhibited synergistic inhibitory effects at low concentration. The binding of rutin/quercetin with PL caused the fluorescence quenching of protein. Fluorescence titration showed the binding affinity of quercetin with PL protein was stronger than that of rutin. Circular dichroism analysis showed the binding changed the secondary structure of PL with an increase in random coil and a decrease in α-Helix and β-Sheet. Molecular docking revealed that rutin and quercetin could interact with the amino acid residues around the catalytic site through multiple secondary interactions. In vivo studies showed that FSI extract can reduce fat absorption and promote fecal fat excretion through inhibition of PL activity, and the effects were mainly due to rutin and quercetin.

Identification and quantification of flavonoids in edible dock based on UPLC-qTOF MS/MS and molecular networking

Edible dock, also known as Rumex patientia L.×Rumex tianschanicus A. LOS., exhibiting the characteristics of high yield, high protein and high nutrition, is widely used in the functional food industry and Chinese herbal medicine while short of secondary metabolites research. This study used UPLC-qTOF MS with two ion polarity in conjunction with Molecular Networking from Global Natural Products Social (GNPS) platform. Then, these 16 flavonoid substances including quercetin derivatives and kaempferol derivatives, firstly were identified from leaves in edible dock and were systematically investigated by UPLC-qTOF MS/MS. MS/MS experiments found that quercetin derivatives have five common characteristic ions, including m/z 300, m/z 271, m/z 255, m/z 243, and m/z 151. In addition, kaempferol derivatives have three common characteristic ions, including m/z 284, m/z 255, and m/z 227. Subsequently, 7 representative constituents were quantified via UPLC-QQQ MS with chemometrics, and the total content of 7 major flavonoids in its dry leaves is 6.988 mg/g in the 21st day samples. The work provided abundant metabolites information of flavonoids in edible dock, and the common characteristic ions will facilitate the building blocks-based molecular network (BBMN) to predict novel framework compounds from quercetin derivatives and kaempferol derivatives, laying the basis for exploitation of edible dock in the fields of pharmaceuticals, health food, and livestock feed.

Characterization and identification of major flavonoids of bamboo leaf extract by HPLC/ESI-QTOF-MS/MS

Bamboo leaf extract (BLE) is a pale brown powder extracted from bamboo leaves, and it is listed in the Chinese Standard GB-2760 as a legal and safe food additive. The present study aims to identify and characterize the major flavonoids in BLE. The identification of major flavonoids was carried out using ultra performance liquid chromatography combined with electrospray ionization quadruple time-of-flight tandem mass spectrometry (HPLC/ESI-QTOF-MS/MS). A total of 31 flavonoid compounds were identified and tentatively characterized base on reference standards and MS dissociation mechanisms. HPLC/ESI-QTOF-MS can serve as an important analytical platform to identification structure of bamboo leaf flavonoids (BLF).

Luteolin-7-O-β-d-Glucuronide Attenuated Cerebral Ischemia/Reperfusion Injury: Involvement of the Blood-Brain Barrier.

Ischemic stroke is a common cerebrovascular disease with high mortality, high morbidity, and high disability. Cerebral ischemia/reperfusion injury seriously affects the quality of life of patients. Luteolin-7-O-β-d-glucuronide (LGU) is a major active flavonoid compound extracted from Ixeris sonchifolia (Bge.) Hance, a Chinese medicinal herb mainly used for the treatment of coronary heart disease, angina pectoris, cerebral infarction, etc. In the present study, the protective effect of LGU on cerebral ischemia/reperfusion injury was investigated in an oxygen-glucose deprivation/reoxygenation (OGD/R) neuronal model and a transient middle cerebral artery occlusion (tMCAO) rat model. In in vitro experiments, LGU was found to improve the OGD/R-induced decrease in neuronal viability effectively by the MTT assay. In in vivo experiments, neurological deficit scores, infarction volume rates, and brain water content rates were improved after a single intravenous administration of LGU. These findings suggest that LGU has significant protective effects on cerebral ischemia/reperfusion injury in vitro and in vivo. To further explore the potential mechanism of LGU on cerebral ischemia/reperfusion injury, we performed a series of tests. The results showed that a single administration of LGU decreased the content of EB and S100B and ameliorated the abnormal expression of tight junction proteins ZO-1 and occludin and metalloproteinase MMP-9 in the ischemic cerebral cortex of the tMCAO 24-h injury model. In addition, LGU also improved the tight junction structure between endothelial cells and the degree of basement membrane degradation and reduced the content of TNF-α and IL-1β in the brain tissue. Thereby, LGU attenuated cerebral ischemia/reperfusion injury by improving the permeability of the blood-brain barrier. The present study provides new insights into the therapeutic potential of LGU in cerebral ischemia.

A comparative study of the antifungal efficacy and phytochemical composition of date palm leaflet extracts

Abstract This study rigorously evaluated the inhibitory effects of chloroform (PDCL) and methanol (PDML) extracts from date palm (Phoenix dactylifera L.) leaflets, in comparison to fosetyl-aluminum, against molecularly identified fungal strains Fusarium oxysporum (OR116511), Botrytis cinerea (OR116493), and Rhizoctonia solani (OR116530) isolated from date palm tree roots and fruits. We found that coumaric acid (1663.91 µg g−1) is one of the top four high-performance liquid chromatography-major phenols in the PDML extract, while the PDCL extract includes rosmarinic acid (291.08 µg g−1). The major flavonoids in the PDML extract are naringenin and kaempferol, whereas PDCL extract includes naringenin and quercetin. In the PDML extract, methyl 9-cis-11-trans-octadecadienoate (9.96%) is one of the top five gas chromatography–mass spectrometry major compounds; likewise, cis-13-octadecenoic acid (26.16%) is in the PDCL extract. The highest growth inhibition percentages of PDCL and PDML extracts were initiated against F. oxysporum (60.53 and 50.00%) at 150 µg mL−1, respectively, whereas inhibition against B. cinerea was realized at the highest concentration with 50.82%. Fosetyl-Al potently inhibited the growth of fungal isolates to varying degrees. Therefore, we could successfully employ PDCL extract to control the growth of F. oxysporum and B. cinerea and also use both extracts against R. solani.

Wedelolactone from Eclipta prostrata (L) L. suppresses inflammation and improves insulin resistance

Objective: To evaluate the effects of wedelolactone, a major flavonoid from Vietnamese Eclipta prostrata (L) L., on inflammation and insulin resistance. Methods: Wedelolactone was extracted from the leaves of Vietnamese Eclipta prostrata (L.) L. with methanol by Soxhlet. The effects of wedelolactone on lipopolysaccharide (LPS)-induced cytokine production, reactive oxygen species (ROS) generation, and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activities in Raw 264.7 cells were measured by enzyme-linked immunosorbent assay (ELISA), specific immunofluorescent dyes and luminometric analysis, respectively. In addition, its effects on glucose uptake and the protein expression of insulin receptor substrate 1 (IRS1) and glucose transporter 4 (GLUT4) were examined in 3T3-L1 cells by immunofluorescent dyes and Western blot. Results: Wedelolactone at 30 μg/mL significantly inhibited LPS-induced production of tumor necrosis factor-α, interleukin (IL)-6, and IL-8 (P<0.01) with no noticeable effects on IL-10 level. It also reduced ROS generation and NADPH oxidase activities in LPS-stimulated Raw 264.7 cells (P<0.01). Furthermore, wedelolactone showed anti-insulin resistance activity, as evidenced by improved glucose uptake and the upregulated expression of IRS1 and GLUT4 in 3T3-L1 cells (P<0.01). Conclusions: Wedelolactone exhibits anti-inflammation and anti-insulin resistance effects, which may be used for the treatment of diabetes and inflammation-associated diseases.

Flavonoids from the leaves and stems of Sedum japonicum var. senanense and their antioxidant activity

Twenty flavonoids (1−20) were isolated from the leaves and stems of Sedum japonicum var. senanense endemic to Japan. Among them, nine compounds were reported in nature for the first time, and identified as herbacetin 3-O-neohesperidoside-8-O-(2‴-acetylxyloside) (2), gossypetin 8-O-(2″-acetylxyloside) (4), gossypetin 8-O-(3″-acetylxyloside) (5), gossypetin 3-O-glucoside-8-O-(3‴-acetylxyloside) (9), gossypetin 3-O-glucoside-8-O-(2‴,3‴-diacetylxyloside) (10), gossypetin 3-O-neohesperidoside-8-O-xyloside (11), gossypetin 3-O-neohesperidoside-8-O-(2⁗-acetylxyloside) (12), gossypetin 3-O-neohesperidoside-8-O-(3⁗-acetylxyloside) (13) and gossypetin 3-O-glucoside-8-O-xylofuranoside (14) by UV spectral survey, HR-MS, LC-MS, acid hydrolysis, NMR including 1H and 13C NMR, COSY, NOESY, HSQC and HMBC. Moreover, nine major flavonoids were surveyed for antioxidant activity by H-ORAC method. As the results, gossypetin 3-O-glucoside-8-O-(2‴-acetylxyoside) (8) showed the highest antioxidant activity. Conversely, gossypetin 3-O-neohesperidoside-8-O-xyloside (11) and gossypetin 3-O-neohesperidoside-8-O-(2⁗-acetylxyloside) (12) which attach neohesperidose showed the lowest values.

Diabetic Neuropathy: An Overview of Molecular Pathways and Protective Mechanisms of Phytobioactives.

Diabetic neuropathy (DN) is a common and debilitating complication of diabetes mellitus that affects the peripheral nerves and causes pain, numbness, and impaired function. The pathogenesis of DN involves multiple molecular mechanisms, such as oxidative stress, inflammation, and pathways of advanced glycation end products, polyol, hexosamine, and protein kinase C. Phytochemicals are natural compounds derived from plants that have various biological activities and therapeutic potential. Flavonoids, terpenes, alkaloids, stilbenes, and tannins are some of the phytochemicals that have been identified as having protective potential for diabetic neuropathy. These compounds can modulate various cellular pathways involved in the development and progression of neuropathy, including reducing oxidative stress and inflammation and promoting nerve growth and repair. In this review, the current evidence on the effects of phytochemicals on DN by focusing on five major classes, flavonoids, terpenes, alkaloids, stilbenes, and tannins, are summarized. This compilation also discusses the possible molecular targets of numerous pathways of DN that these phytochemicals modulate. These phytochemicals may offer a promising alternative or complementary approach to conventional drugs for DN management by modulating multiple pathological pathways and restoring nerve function.

Solid lipid nanoparticle: A potent vehicle of the kaempferol for brain delivery through the blood-brain barrier in the focal cerebral ischemic rat

Kaempferol is major flavonoid present in Convolvulus pluricaulis. This phytochemical protects the brain against oxidative stress, neuro-inflammation, neurotoxicity, neurodegeneration and cerebral ischemia induced neuronal destruction. Kaempferol is poorly water soluble. Our study proved that solid lipid nanoparticles (SLNs) were efficient carrier of kaempferol through blood-brain barrier (BBB). Kaempferol was incorporated into SLNs prepared from stearic acid with polysorbate 80 by the process of ultrasonication. Mean particle size and zeta potential of kaempferol loaded solid lipid nanoparticles (K-SLNs) were 451.2 nm and −15.0 mV. Atomic force microscopy showed that K-SLNs were spherical in shape. Fourier transformed infrared microscopy (FTIR) showed that both stearic acid and kaempferol were present in K-SLNs. X-ray diffraction (XRD) and differential scanning calorimetry (DSC) revealed that the matrices of K-SLNs were in untidy crystalline state. Entraptment efficiency of K-SLNs was 84.92%. In-vitro drug release percentage was 93.24%. Kaempferol loaded solid lipid nanoparticles (K-SLNs) showed controlled release profile. In-vitro uptake study showed significant efficiency of K-SLNs to cross blood-brain barrier (BBB). After oral administration into the focal cerebral ischemic rat, accumulation of fluorescent labeled K-SLNs was observed in the brain cortex which confirmed its penetrability into the brain. It significantly decreased the neurological deficit, infarct volume and level of reactive oxygen species (ROS) and decreased the level of pro-inflammatory mediators like NF-κB and p-STAT3. Damaged neurons and brain texture were improved. This study indicated increased bioavailability of kaempferol into the brain tissue through SLNs formulation.

Fate of flavonoids and theobromine in cocoa beans during roasting: Effect of time and temperature

AbstractThe content of phenolic compounds in chocolate depends on the processing of the cocoa from bean to bar. The aim of this study was to determine the fate of phenolic compounds and theobromine in cocoa beans during roasting at different temperatures. Based on a screening of 12 cocoa bean sorts, three beans (NM, NCC, and NB) with initial high total phenolic content (TPC) were selected for the roasting trial (100 and 150°C up to 20 min). The concentration of three major flavonoids ((−)‐catechin, (−)‐epicatechin and procyanidin B2) and one methylxanthine (theobromine) were evaluated in both raw and roasted beans. Results showed changes in the concentration of flavonoids and theobromine during roasting. Roasting at 150°C for 15 min was optimal for maintaining high flavonoid levels while reducing theobromine levels. However, sensory evaluation on final product is needed to confirm whether the suggested roasting condition would also result in a final product with pleasant sensory properties.

Anti-Aging Potential of the Two Major Flavonoids Occurring in Asian Water Lily Using In Vitro and In Silico Molecular Modeling Assessments.

Our previous study investigated the major flavonoids and antioxidant potential of Asian water lily (Nymphaea lotus L., family Nymphaeaceae) stamens and perianth extracts. Quercetin-3-O-rhamnoside (Que-3-Rha) and kaempferol-3-O-galactoside (Kae-3-Gal) were reported as the two most prominent flavonoids found in these extracts. Many flavonoids have been reported on the skin anti-aging effect that are useful for cosmeceutical/phytopharmaceutical application. However, Que-3-Rha and Kae-3-Gal occurring in this medicinal plant have not yet been evaluated for their ability to inhibit skin-aging enzymes. Therefore, this study aimed (1) to assess the enzyme inhibitory activity of Que-3-Rha and Kae-3-Gal, and (2) to conduct molecular modeling of these compounds against critical enzymes involved in skin aging such as collagenase, elastase, and tyrosinase. In vitro enzymatic assays demonstrated that both of the two most prominent flavonoids exhibited moderate to good inhibitory activity toward these enzymes. These experimental findings were supported by molecular docking analysis, which indicated that Que-3-Rha and Kae-3-Gal showed superior binding affinity to the target enzymes compared to the positive controls. Additionally, computational predictions suggested favorable skin permeability and no severe toxicity for both compounds. The results from molecular dynamic (MD) simulation revealed that all the complexes remained stable during the 200 ns MD simulation. Structural analyses and binding free energy calculations also supported the inhibitory potential of these two flavonoids against skin-aging enzymes. In conclusion, this study provides valuable insights into the anti-aging potential of the two major flavonoids occurring in this medicinal plant, paving the way for further development of cosmeceutical/phytopharmaceutical products targeting skin aging.

Deciphering characteristics of Macaranga tanarius leaves extract with electron shuttle-associated anti-inflammatory activity via microbial fuel cells, molecular docking, and network pharmacology

Recent studies have shown that the potential disease-treating characteristics of traditional Chinese medicine (TCM) were associated with electron-shuttling and bioenergy-stimulating capabilities. These redox-mediating characteristics are possibly even beneficial in the treatment of a wide variety of diseases ranging from viral infections to inflammations. This first-attempt study tended to investigate electron-mediating and bioenergy-extracting potentials of Macaranga tanarius leaves extract using dual chamber microbial fuel cells (MFCs) to unveil correlations of the anti-inflammatory potential for value-added applications. Network pharmacology and molecular docking studies were conducted with compounds identified to own electron-shuttling capabilities in the leaves extract to determine inhibitory activity with inflammation receptors. M. tanarius has shown significant bioenergy-stimulating characteristics, with the water extract having a 1.72±0.21-fold power generation. The underlying mechanism of action of M. tanarius was proposed via network pharmacology, suggesting how it targets specific proteins to inhibit potential diseases, such as kidney nephropathy. The findings revealed that major flavonoids bound to receptors via hydrogen bonds and π-interactions stabilizing the protein-ligand complex. Thus, exhibiting a high binding affinity with inflammation receptors, suggesting how it targets specific proteins to inhibit potential diseases.

Higher Dietary Quercetin Intake Is Associated with Lower Risk of Adverse Outcomes among Individuals with Inflammatory Bowel Disease in a Prospective Cohort Study

BackgroundCumulative preclinical evidence reported quercetin, a major flavonoid, can attenuate the disease activity of inflammatory bowel diseases (IBD). However, there is limited evidence that supports the benefits of quercetin for patients with IBD. ObjectivesTo investigate whether dietary quercetin intake is associated with adverse outcomes among individuals with IBD in a prospective cohort study. MethodsWe included 2293 participants with IBD (764 Crohn’s disease [CD] and 1529 ulcerative colitis [UC]) from the UK Biobank. Dietary information was collected using validated 24-h dietary assessments, and quercetin intake was estimated based on national nutrient databases. Two outcomes, enterotomy and all-cause mortality, were obtained based on the national data. Cox proportional hazard models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs). ResultsAfter a mean (standard deviation) follow-up of 9.6 (1.8) y, we documented 193 enterotomy events and 176 deaths. Compared with participants with the lowest quartile intake of quercetin, those in the highest quartiles were associated with lower risk of enterotomy (HR: 0.46; 95% CI: 0.28, 0.76) and all-cause mortality (HR: 0.53; 95% CI: 0.33, 0.83) in IBD. The inverse associations between quercetin and enterotomy were consistent in CD (HR: 0.30; 95% CI: 0.12, 0.78) but not UC (HR: 0.58; 95% CI: 0.32, 1.07), while the inverse associations between quercetin and mortality were consistent both in CD (HR: 0.37; 95% CI: 0.15, 0.92) and UC (HR: 0.55; 95% CI: 0.31, 0.95). ConclusionsHigher dietary intake of quercetin was associated with lower risk of enterotomy and all-cause mortality in IBD. Our study provides novel evidence that further suggests the benefits of quercetin for patients with IBD, while also calling for further validation in other cohorts and clinical trials.

In vitro simulated saliva, gastric, and intestinal digestion followed by faecal fermentation reveals a potential modulatory activity of Epimedium on human gut microbiota

Herba Epimedii, known for its rich array of bioactive ingredients and widespread use in ethnopharmacological practices, still lacks a comprehensive understanding of its gastrointestinal biotransformation. In this study, we qualitatively explored the dynamic changes in Epimedium sagittatum components during in vitro simulated digestions, with a quantitative focus on its five major flavonoids. Notably, significant metabolism of E. sagittatum constituents occurred in the simulated small intestinal fluid and colonic fermentation stages, yielding various low molecular weight metabolites. Flavonoids like kaempferol glycosides were fully metabolized in the simulated intestinal fluid, while hyperoside digestion occurred during simulated colon digestion. Colonic fermentation led to the production of two known bioactive isoflavones, genistein, and daidzein. The content and bioaccessibility of the five major epimedium flavonoids—icariin, epimedin A, epimedin B, epimedin C, and baohuoside I—significantly increased after intestinal digestion. During colon fermentation, these components gradually decreased but remained incompletely metabolized after 72 h. Faecal samples after E. sagittatum fermentation exhibited shift towards dominance by Lactobacillus (Firmicutes), Bifidobacterium (Actinobacteria), Streptococcus (Firmicutes), and Dialister (Firmicutes). These findings enhance our comprehension of diverse stages of Herba Epimedii constituents in the gut, suggesting that the primary constituents become bioaccessible in the colon, where new bioactive compounds may emerge.

The First Comprehensive Chemical Profiling of Vachellia gummifera (Willd.) Kyal. & Boatwr., a Plant with Medicinal Value.

Vachellia gummifera (Willd.) Kyal. & Boatwr. is a medicinal plant endemic to Morocco that has no documented studies on its chemical composition. In this study, the chemical composition of the water/methanol (4 : 1) extracts of air-dried leaf and stem samples of Moroccan V. gummifera was determined using UHPLC-MS and NMR. In total, over 100 metabolites were identified in our study. Pinitol was the major compound in both the leaf and stem extracts, being significantly more abundant in the former. Asparagine and 3-hydroxyheteroendrin were the second most abundant compounds in the stem and leaf extracts, respectively, though both compounds were present in each tissue. The other compounds included flavonoids based on quercetin, and phenolic derivatives. Eucomic acid, only identified in the stems and was the major aromatic compound distinguishing the leaf and stem profiles. Quercetin 3-O-(6''-O-malonyl)-β-D-glucopyranoside was identified as the major flavonoid in the leaves but was also present in the stems. Other malonylated derivatives that were all flavonol glycosides based on myricetin, kaempferol, and isorhamnetin in addition to quercetin were also identified. This is the first report of eucomic acid and malonylated compounds in Vachellia species. This report provides valuable insights into the chemotaxonomic significance of the Vachellia genus.

In vitro Evaluation of Skin Related Enzyme Inhibitory Effect and Emulgel Formulation Development Studies of Onobrychis Argyrea subsp. Argyrea with Phytochemical Analysis.

Species of Onobrychis have been used to treat skin disorders such as wounds and cuts in folk medicine and Onobrychis argyrea subsp. argyrea (OA) commonly known as 'silvery sainfoin', is a member of this genus. In this study, it was aimed to investigate the skin-related biological activities and phytochemical characterization of OA. Moreover, an emulgel formulation was developed from the main methanolic extract of the plant (OAM). Initially, to identifiy of the active fractions, aerial parts of the plant material was extracted with methanol and fractionated by n-hexane, chloroform, ethyl acetate and n-butanol, respectively. Antioxidant activity was determined by CUPRAC, TOAC, FRAP and DPPH assays. Thereafter, the inhibition potential of OAM, novel formulation and all fractions was measured against elastase, collagenase, tyrosinase and hyaluronidase enzymes. OAM was analyzed and characterized by LC/MS-MS. The major bioactive flavonoids which are rutin and isoquercetin were measured and compared as qualitative and quantitative via high performance thin layer chromatography (HPTLC) analysis in OAM and fractions. The results showed that extracts of OA can be a potential cosmeceutical agent for skin related problems.

Quercetin and Kaempferol inhibit HMC-1 activation via SOCE/NFATc2 signaling and suppress hippocampal mast cell activation in lipopolysaccharide-induced depressive mice.

Mast cells (MCs), as the fastest immune responders, play a critical role in the progression of neuroinflammation-related diseases, especially in depression. Quercetin (Que) and kaempferol (Kae), as two major diet-derived flavonoids, inhibit MC activation and exhibit significant antidepressant effect due to their anti-inflammatory capacity. The study aimed to explore the mechanisms of inhibitory effect of Que and Kae on MC activation, and whether Que and Kae suppress hippocampal mast cell activation in LPS-induced depressive mice. In vitro assays, human mast cells (HMC-1) were pretreated with Que or Kae for 1h, then stimulated by phorbol 12-myristate 13-acetate (PMA) and 2,5-di-t-butyl-1,4-benzohydroquinone (tBHQ) for 3h or 12h. In vivo assays, Que or Kae was administered by oral gavage once daily for 14days and then lipopolysaccharide (LPS) intraperitoneally injection to induce depressive behaviors. The secretion and expression of TNF-α were determined by ELISA and Western blotting. The nuclear factor of activated T cells (NFAT) transcriptional activity was measured in HMC-1 stably expressing NFAT luciferase reporter gene. Nuclear translocation of NFATc2 was detected by nuclear protein extraction and also was fluorescently detected in HMC-1 stably expressing eGFP-NFATc2. We used Ca2+ imaging to evaluate changes of store-operated calcium entry (SOCE) in HMC-1 stably expressing fluorescent Ca2+ indicator jGCamP7s. Molecular docking was used to assess interaction between the Que or Kae and calcium release-activated calcium modulator (ORAI). The hippocampal mast cell accumulation and activation were detected by toluidine blue staining and immunohistochemistry with β-tryptase. In vitro assays of HMC-1 activated by PtBHQ (PMA and tBHQ), Que and Kae significantly decreased expression and secretion of TNF-α. Moreover, NFAT transcriptional activity and nuclear translocation of NFATc2 were remarkably inhibited by Que and Kae. In addition, the Ca2+ influx mediated by SOCE was suppressed by Que, Kae and the YM58483 (ORAI inhibitor), respectively. Importantly, the combination of YM58483 with Que or Kae had no additive effect on the inhibition of SOCE. The molecular docking also showed that Que and Kae both exhibit high binding affinities with ORAI at the same binding site as YM58483. In vivo assays, Que and Kae significantly reversed LPS-induced depression-like behaviors in mice, and inhibited hippocampal mast cellactivation in LPS-induced depressive mice. Our results indicated that suppression of SOCE/NFATc2 pathway-mediated by ORAI channels may be the mechanism of inhibitory effect of Que and Kae on MC activation, and also suggested Que and Kae may exert the antidepressant effect through suppressing hippocampal mast cell activation.

Luteolin-7-O-β-d-glucuronide Ameliorates Cerebral Ischemic Injury: Involvement of RIP3/MLKL Signaling Pathway.

Luteolin-7-O-β-d-glucuronide (LGU) is a major active flavonoid glycoside compound that is extracted from Ixeris sonchifolia (Bge.) Hance, and it is a Chinese medicinal herb mainly used for the treatment of coronary heart disease, angina pectoris, cerebral infarction, etc. In the present study, the neuroprotective effect of LGU was investigated in an oxygen glucose deprivation (OGD) model and a middle cerebral artery occlusion (MCAO) rat model. In vitro, LGU was found to effectively improve the OGD-induced decrease in neuronal viability and increase in neuronal death by a 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and a lactate dehydrogenase (LDH) leakage rate assay, respectively. LGU was also found to inhibit OGD-induced intracellular Ca2+ overload, adenosine triphosphate (ATP) depletion, and mitochondrial membrane potential (MMP) decrease. By Western blotting analysis, LGU significantly inhibited the OGD-induced increase in expressions of receptor-interacting serine/threonine-protein kinase 3 (RIP3) and mixed lineage kinase domain-like protein (MLKL). Moreover, molecular docking analysis showed that LGU might bind to RIP3 more stably and firmly than the RIP3 inhibitor GSK872. Immunofluorescence combined with confocal laser analyses disclosed that LGU inhibited the aggregation of MLKL to the nucleus. Our results suggest that LGU ameliorates OGD-induced rat primary cortical neuronal injury via the regulation of the RIP3/MLKL signaling pathway in vitro. In vivo, LGU was proven, for the first time, to protect the cerebral ischemia in a rat middle cerebral artery occlusion (MCAO) model, as shown by improved neurological deficit scores, infarction volume rate, and brain water content rate. The present study provides new insights into the therapeutic potential of LGU in cerebral ischemia.

Integrative Metabolomic and Transcriptomic Analyses Reveal the Mechanism of Petal Blotch Formation in Rosa persica.

Petal blotch is a specific flower color pattern commonly found in angiosperm families. In particular, Rosa persica is characterized by dark red blotches at the base of yellow petals. Modern rose cultivars with blotches inherited the blotch trait from R. persica. Therefore, understanding the mechanism for blotch formation is crucial for breeding rose cultivars with various color patterns. In this study, the metabolites and genes responsible for the blotch formation in R. persica were identified for the first time through metabolomic and transcriptomic analyses using LC-MS/MS and RNA-seq. A total of 157 flavonoids were identified, with 7 anthocyanins as the major flavonoids, namely, cyanidin 3-O-(6″-O-malonyl) glucoside 5-O-glucoside, cyanidin-3-O-glucoside, cyanidin 3-O-galactoside, cyanidin O-rutinoside-O-malonylglucoside, pelargonidin 3-O-glucoside, pelargonidin 3,5-O-diglucoside, and peonidin O-rutinoside-O-malonylglucoside, contributing to pigmentation and color darkening in the blotch parts of R. persica, whereas carotenoids predominantly influenced the color formation of non-blotch parts. Zeaxanthin and antheraxanthin mainly contributed to the yellow color formation of petals at the semi-open and full bloom stages. The expression levels of two 4-coumarate: CoA ligase genes (Rbe014123 and Rbe028518), the dihydroflavonol 4-reductase gene (Rbe013916), the anthocyanidin synthase gene (Rbe016466), and UDP-flavonoid glucosyltransferase gene (Rbe026328) indicated that they might be the key structural genes affecting the formation and color of petal blotch. Correlation analysis combined with weighted gene co-expression network analysis (WGCNA) further characterized 10 transcription factors (TFs). These TFs might participate in the regulation of anthocyanin accumulation in the blotch parts of petals by modulating one or more structural genes. Our results elucidate the compounds and molecular mechanisms underlying petal blotch formation in R. persica and provide valuable candidate genes for the future genetic improvement of rose cultivars with novel flower color patterns.