High throughput chemiluminescence platform for evaluating antioxidative activity of total flavonoid glycosides from plant extracts

Study on quality difference between Belamcanda chinensis (L.) DC and Iris tectorum Maxim. based on chemical chromatogram analysis, biological activity evaluation and in vivo distribution rule

ETHNOPHARMACOLOGICAL RELEVANCE

Belamcanda chinensis (L.) DC. (BC) and Iris tectorum Maxim. (ITM) have been widely used in recent years due to their remarkable curative effects on sore throat, cough and asthma. but they are often misused due to their similar appearance. A comprehensive comparison of the chemical composition, biological activity, pharmacokinetics and tissue distribution between the two active differential components has not been performed. Differences in their specific effects have not been fully elucidated.

AIM OF THE STUDY

This work aims at differentiating between BC and ITM in terms of appearance, chemical composition, biological activity, pharmacokinetics and tissue distribution.

MATERIALS AND METHODS

In this study, the HPLC-FP method was used to find the differences between the chemical components of BC and ITM. The pharmacological experiments were used to compare the differences in activity, including in vitro anti-inflammatory activity with LPS-induced inflammation model of RAW 264.7 cells, inhibition of AChE activity, and the regulation of isolated small intestinal smooth muscle in mice. The pharmacokinetic and tissue distribution profiles were used to analyze the differences between the two in rats.

RESULTS

The types of isoflavones in BC and ITM are basically the same, but their contents in ITM is much higher than that in BC. At the same doses, the release of TNF-α, NO, IL-1β and IL-6 from RAW 264.7 cells in the ITM group was lower than that of the BC group, and the in vitro anti-inflammatory activity of ITM was stronger than that of BC. Meanwhile, ITM had stronger inhibition ability to inhibit AChE activity than BC. The BC extract exhibited an inhibitory effect on the isolated small intestinal smooth muscle of mice, and the ITM extract showed stimulatory effect at low concentration and inhibitory effect at high concentration. There were significant differences in drug-time profiles, kinetic parameters and tissue distribution.

CONCLUSIONS

There are significant differences in the multidimensional aspects of appearance, chemical composition, biological activity, pharmacokinetics, and tissue distribution between BC and ITM. This study provides a theoretical basis for the quality control, pharmacological efficacy and clinical application of the two herbs.

Protective effect of Eucommia ulmoides Oliver male flowers on ethanol-induced DNA damage in mouse cerebellum and cerebral cortex

Ethanol is a principal ingredient of alcoholic beverages with potential neurotoxicity and genotoxicity, and the ethanol-associated oxidative DNA damage in the central nervous system is well documented. Natural product may offer new options to protect the brain against ethanol-induced neurotoxicity. The male flower of Eucommia ulmoides (EUF) Oliver has been extensively utilized as the tea, the healthy hot drink on the market. In this study, 19 constituents in the effective fraction of EUF were identified by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). In the single-cell gel electrophoresis assay, EUF was observed to ameliorate DNA damage in mouse cerebellum and cerebral cortex caused by acute ethanol administration, which was further confirmed by the morphological observation. The protective effects of EUF were associated with increasing total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-PX) activities, and a decrease in nitric oxide (NO), malondialdehyde (MDA), 8-hydroxy-2'-deoxyguanosine (8-OHdG), and kelch-like ECH-associated protein-1 (Keap1) levels. Molecular docking results demonstrated that compounds 4, 7, 9, and 16 from EUF have a strong affinity to the Keap1 Kelch domain to hinder the interaction of nuclear factor-erythroid 2-related factor 2 (Nrf2) with Keap1. These findings suggest that EUF is a potent inhibitor of ethanol-induced brain injury possibly via the inhibition of oxidative stress.

Multimodal integrated strategy for the discovery and identification of quality markers in traditional Chinese medicine

With the modernization and internationalization of traditional Chinese medicine (TCM), the requirement for quality control has increased. The quality marker (Q-marker) is an important standard in this field and has been implemented with remarkable success in recent years. However, the establishment of Q-markers remains fragmented and the process lacks systematicity, resulting in inconsistent quality control and insufficient correlation with clinical efficacy and safety of TCM. This review introduces four multimodal integrated approaches that contribute to the discovery of more comprehensive and accurate Q-markers, thus aiding in the establishment of new quality control patterns based on the characteristics and principles of TCM. These include the whole-process quality control strategy, chemical-activity-based screening method, efficacy, safety, and consistent combination strategy, and TCM theory-guided approach. Furthermore, methodologies and representative examples of these strategies are described, and important future directions and questions in this field are also proposed.

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Four multimodal integrated strategies were introduced to establish Q-markers.

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Quality control of TCM should focus on the entire process chain.

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The identification of Q-markers needs to be guided by TCM theory.

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Ensuring efficacy, safety, and consistency is an essential goal of Q-markers.

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Multidisciplinary techniques are the driving force for improving Q-markers.

A novel strategy to evaluate the quality of herbal products based on the chemical profiling, efficacy evaluation and pharmacokinetics

The purpose of this study was to establish a chemical profiling method to compare the chemical composition of herbal products by using extracts of Belamcandae Rhizoma(EBR) extracted with different polarity solvent as an example, and evaluate the quality of EBR based on the analysis of chemical profiling, efficacy evaluation and pharmacokinetics. As seen from the results of chemical profiling, the PCA and PLS-DA score plot indicated that the dots of Belamcandae Rhizoma water extracts were separated from ethanol extracts obviously, which suggested significant differences of chemical profiling existing in the different solvent extracts. The PCA and PLS-DA loading plot illustrated that the main compounds contributing to chemical profiling differences were tectoridin(TD), iristectorin B(IT B), iridin(ID), tectorigenin(TG), irigenin(IG), iristectorigein A(IG A), dichotomitin(DT) and irisflorentin(IF). Furthermore, the results of HPLC analysis demonstrated that the contents of these main compounds in ethanol extracts were significantly higher than that in water extracts (P < 0.01). Both the pharmacological and hematoxylin-eosin staining studies indicated that the ethanol extracts of Belamcandae Rhizoma had a better therapeutic effect than water extracts in oral ulcer model rats (P<0.01). It is suggested that the ethanol extracts were beneficial to the absorption and bioavailability of TG which was one of the most important bioactive compounds of Belamcandae Rhizoma in pharmacokinetic study in rats. This work provided a novel method to optimize the extraction process of EBR and related herbal products. Compared with the conventional chemical fingerprint methodology, the approach proposed above is not only a powerful tool to identify efficacy-related components for the quality evaluation, but also can be used to predict the therapeutic efficacy of herbal products.

A strategy for integrated pharmacokinetic study of cardiovascular herbal medicines based on chemiluminescence and HPLC-MS/MS assays: a case using Danshen injection

A strategy for an integrated PK study based on chemiluminescence assays for cardiovascular herbal medicines with antioxidants as the main effective substances.

Rapid determination of major bioactive isoflavonoid compounds during the extraction process of kudzu (Pueraria lobata) by near-infrared transmission spectroscopy

Near-infrared (NIR) spectroscopy has been developed into an indispensable tool for both academic research and industrial quality control in a wide field of applications. The feasibility of NIR spectroscopy to monitor the concentration of puerarin, daidzin, daidzein and total isoflavonoid (TIF) during the extraction process of kudzu (Pueraria lobata) was verified in this work. NIR spectra were collected in transmission mode and pretreated with smoothing and derivative. Partial least square regression (PLSR) was used to establish calibration models. Three different variable selection methods, including correlation coefficient method, interval partial least squares (iPLS), and successive projections algorithm (SPA) were performed and compared with models based on all of the variables. The results showed that the approach was very efficient and environmentally friendly for rapid determination of the four quality indices (QIs) in the kudzu extraction process. This method established may have the potential to be used as a process analytical technological (PAT) tool in the future.

Chemical composition and antioxidant activities of extracts from Apocyni Veneti Folium

An expeditious and effective HPLC-UV method has been developed for the simultaneous determination of seven major flavonoids in Apocyni Veneti Folium (AVF) extract. The chemical profile of seven flavonoids, including quercetin-3-O-β-D-glc(2 → 1)-β-D-glucoside, rutin, isoquercetin, kaempferol-3-O-β-D-glucoside, quercetin-3-O-(6″-O-malonyl)-β-D-glucoside, quercetin and kaempferol was acquired by HPLC-UV. The analysis was performed on a Diamosil C18 analytical column with a gradient solvent system of acetonitrile-0.1% aqueous acetic acid. Full validation of the method was carried out (linearity, reproducibility, repeatability, accuracy and limit of detection). The results indicated that the contents of investigated flavonoids in Apocyni Veneti Folium varied significantly from habitat to habitat, with contents ranging from 0.01 to 5.57 mg g⁻¹. The antioxidant activity results demonstrate that the seven flavonoids showed great efficiency in scavenging DPPH radicals. The high content of flavonoid components of AVF could be responsible for its high antioxidant activity. This study provides powerful evidence for the relationship between the chemical ingredients of and bioactivity in AVF.

Cardioprotective effects of Glycyrrhiza uralensis extract against doxorubicin-induced toxicity

The purpose of the present study was to investigate the cardioprotective effects of Glycyrrhiza uralensis extract (GUE) against doxorubicin (DOX)-induced cardiotoxicity. Imprinting control region (ICR) mice were treated with saline, DOX (20 mg/kg intraperitoneal [ip] for once), GUE (100 mg/kg intragastric [ig] for 8 days), co-treatments with DOX and GUE (100 mg/kg ig for 8 days), and amifostine (100 mg/kg intravenous [iv] for once), respectively. Serum levels of lactate dehydrogenase (LDH) and creatine kinase isoenzyme (CK-MB), glutathione peroxidase (GSH-P(X)) activity, and glutathione (GSH) level in heart tissue were measured. Histopathologic analysis of heart tissue was also performed. Treatment with GUE significantly protected the mice from DOX-induced cardiotoxicity, indicated by decreased levels of serum LDH and CK-MB, improved heart morphology and increased GSH-P(X) activity and GSH level. Additionally, GUE did not compromise the tumor-inhibitory effect of DOX. In conclusion, our studies imply the potentially clinical application of GUE to overcome the cardiotoxicity of doxorubicin.

Chinese medicine Nao-Shuan-Tong attenuates cerebral ischemic injury by inhibiting apoptosis in a rat model of stroke

ETHNOPHARMACOLOGICAL RELEVANCE

Nao-Shuan-Tong (NST) in capsule form is a compound prescription formulated according to the meridian theory of traditional Chinese medicine (TCM) and is approved by the State Food and Drug Administration of China for the treatment of ischemic stroke.

OBJECTIVES

To test the neuroprotective effects of the Chinese medicine Nao-Shuang-Tong on cerebral ischemia in rats and to explore the underlying mechanisms.

MATERIALS AND METHODS

115 Male Sprague-Dawley rats were randomly divided into 5 groups: sham, ischemia-reperfusion (I/R), and I/R plus NST 0.25, NST 0.5 and NST 1 (n=23 in each group). Cerebral ischemia was induced by 1.5h of middle cerebral artery occlusion. Cerebral infarct area was measured by tetrazolium staining at 24h following reperfusion, and neurological functional deficits were assessed at 1, 3, 7 and 14 d after reperfusion. Neuronal apoptosis was studied by Nissl staining and DNA fragmentation assay at 1 and 3d after reperfusion. The activation of caspase-3, -8, -9 and Bax/Bcl-2 levels were analyzed by western blot 24h after reperfusion.

RESULTS

NST (0.5 and 1g/kg) significantly reduced cerebral infarct area, attenuated neurological functional deficits, and reduced neuronal apoptosis in ischemic cortex and in the CA1 region of hippocampus. NST also suppressed overexpression of Bax and activated caspases-3, -8 and -9, and also inhibited the reduction of Bcl-2 expression and markedly depressed the Bax/Bcl-2 ratio.

CONCLUSIONS

These findings demonstrate that NST is neuroprotective against cerebral ischemia and is likely to act via inhibition of neuronal apoptosis associated with changes in levels of caspases-3 and -8, Bax and Bcl-2.