luteolin-7-o-glucuronide and luteolin-7-glucoside

Flos Lonicerae Japonicae (FLJ), the flower bud of Lonicera japonica Thunb. (Caprifoliaceae), is a widely used traditional Chinese medicine with various pharmacological activities. Luteoloside is a major active compound and a quality control marker of FLJ. Luteolin-7-O-glucuronide (LG), an analog of luteoloside, was conjugated with bovine serum albumin (BSA) and ovalbumin (OVA) to create the immunogen and coating antigen, respectively. A sensitive and specific monoclonal antibody (mAb), designated as mAb3A4, was generated with LG-BSA. To screen the authenticity and quality of FLJ, an indirect competitive enzyme-linked immunosorbent assay (icELISA) was established. The concentration of luteoloside producing 50 % inhibition and the working range of the icELISA were 42.3 and 9.1-258.1 μg L(-1), respectively. The icELISA showed cross-reactivity values of 2414, 402, 230, and <1 % for LG, baicalin, scutellarin, and other analogs of luteoloside, respectively. The average recovery of luteoloside in the FLJ samples as determined by icELISA ranged from 83.0 to 112.5 %. The luteoloside content was determined for different Lonicera herbal samples with icELISA, and the results were confirmed by high-performance liquid chromatography analysis. Thus, this icELISA is suitable for the quality assurance of FLJ samples. Graphical abstract Specific monoclonal antibody-based enzyme-linked immunosorbent assay for luteoloside.

Topics: Animals; Antibodies, Monoclonal; Antibody Formation; Cell Line; Enzyme-Linked Immunosorbent Assay; Female; Glucosides; Haptens; Lonicera; Luteolin; Mice, Inbred BALB C; Plant Extracts

Herbal medicinal products are commonly used in alternative treatment of menopausal hot flushes. In a recent clinical study, Salvia officinalis tincture was found to reduce hot flush frequency and intensity. The aim of the current study was the investigation of the mechanism(s) responsible for the anti-hot flush activity of S. officinalis and determination of its active principle(s). The 66% ethanolic tincture, as well as the n-hexane, CHCl₃, and aqueous ethanolic subextracts obtained from the tincture were studied in vitro for two of the most relevant activities, estrogenicity and selective serotonin reuptake inhibition. Because of an increased risk of menopausal women to suffer from Alzheimer's disease, an in vitro acetylcholinesterase inhibition assay was also employed. No activity was observed in the selective serotonin reuptake inhibition or the acetylcholinesterase inhibition assays at the highest test concentrations. The tincture showed no estrogenic effects whereas the aqueous ethanolic subextract exhibited estrogenicity in the ERLUX assay with an EC₅₀ value of 64 µg/mL. Estrogenic activity-guided fractionation of the aqueous ethanolic subextract by a combination of reverse-phase vacuum liquid chromatography and gel chromatography identified luteolin-7-O-glucuronide (EC₅₀ 129 µg/mL) as the active component of the vacuum liquid chromatography fraction 4 (EC₅₀ 69 µg/mL). Luteolin-7-O-glucoside was identified as the putative estrogenic principle of the most potent minor fraction (7.6.7.6, EC₅₀ 0.7 µg/mL) obtained from the initial vacuum liquid chromatography fraction 7 (EC₅₀ 3 µg/mL). This study suggests the involvement of common and ubiquitous estrogenic flavonoids in the anti-hot flush effect of Salvia officinalis, a safe and commonly used herbal medicinal product during the menopause.

Topics: Cholinesterase Inhibitors; Drug Evaluation, Preclinical; Estrogens; Female; Flavones; Glucosides; HEK293 Cells; Hot Flashes; Humans; Luteolin; Menopause; Plant Extracts; Plants, Medicinal; Salvia officinalis; Selective Serotonin Reuptake Inhibitors

A rapid, sensitive and selective ultra-fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) method for the simultaneous determination of three active flavonoid glycosides: luteolin-7-O-gentiobioside, luteolin-7-O-β-D-glucoside and luteolin-7-O-β-D-glucuronide in beagle dog plasma was developed and validated. Puerarin was used as internal standard (IS). After protein precipitation with acidified acetonitrile, the analytes were separated on a Venusil MP C18 column with a gradient elution system composed of 0.05% formic acid and acetonitrile at a flow rate of 0.4ml/min. Detection was performed using multiple reaction monitoring (MRM) mode with a turbo ion spray source under a negative ionization condition. The calibration curves of the three analytes showed good linearity (r>0.995) within the tested concentration ranges. The lower limits of quantification for luteolin-7-O-gentiobioside, luteolin-7-O-β-D-glucoside and luteolin-7-O-β-D-glucuronide were 1.0 ng/ml, 1.0 ng/ml and 4.0 ng/ml, respectively. The intra-day and inter-day precision and accuracy deviations were less than 15%, and the extraction recoveries of the three analytes from beagle dog plasma were more than 75%. The validated method was successfully applied to a pharmacokinetic study of the three flavonoid glycosides in beagle dog plasma after intravenous administration of the traditional Chinese medicinal preparation: Kudiezi injection.

Topics: Animals; Calibration; Chromatography, High Pressure Liquid; Dogs; Drugs, Chinese Herbal; Flavones; Flavonoids; Glucosides; Isoflavones; Luteolin; Medicine, Chinese Traditional; Tandem Mass Spectrometry

Two new iridoid diesters of glucopyranose were isolated from the aerial part of Linaria canadensis (L.) Dum. Eight known flavones, apigenin, diosmetin, genkwanin, luteolin, luteolin 7-O-glucoside, luteolin 7-O-glucuronide, genkwanin 4'-O-rutinoside, and quercetin 7-O-rutinoside were also isolated. The chemical structures of the isolated compounds were elucidated based on the analyses of the spectroscopic data.

Topics: Flavones; Flavonoids; Glucosides; Iridoids; Linaria; Luteolin; Magnetic Resonance Spectroscopy; Molecular Structure; Quercetin