Target-guided isolation and purification of cyclooxygenase-2 inhibitors from Meconopsis integrifolia (Maxim.) Franch. by high-speed counter-current chromatography combined with ultrafiltration liquid chromatography

Meconopsis integrifolia (Maxim.) Franch. is used extensively in traditional Tibetan medicine for its potent anti-inflammatory properties. In this study, six cyclooxygenase-2 (COX-2) inhibitors were purified from M. integrifolia using high-speed counter-current chromatography guided by ultrafiltration liquid chromatography (ultrafiltration-LC). First, ultrafiltration-LC was performed to profile the COX-2 inhibitors in M. integrifolia. The reflux extraction conditions were further optimized using response surface methodology, and the results showed that the targeted COX-2 inhibitors could be well enriched under the optimized extraction conditions. Then the six target COX-2 inhibitors were separated by high-speed countercurrent chromatography with a solvent system composed of ethyl acetate/n-butanol/water (4:1:4, v/v/v. Finally, the six COX-2 inhibitors, including 21.2 mg of 8-hydroxyluteolin 7-sophoroside, 29.6 mg of 8-hydroxyluteolin 7-[6'''-acetylallosyl-(1→2)-glucoside], 42.5 mg of Sinocrassoside D3, 54.1 mg of Hypolaetin 7-[6'''-acetylallosyll-(l→2)-3''-acetylglucoside, 30.6 mg of Hypolaetin 7-[6'''-acetylallosyll-(l→2)-6''-acetylglucoside and 17.8 mg of Hypolaetin were obtained from 500 mg of sample. Their structures were elucidated by 1 H-NMR spectroscopy. This study reveals that ultrafiltration-LC combined with high-speed counter-current chromatography is a robust and efficient strategy for target-guided isolation and purification of bioactive molecules. It also enhances the scientific understanding of the anti-inflammatory properties of M. integrifolia but also paves the way for its further medicinal applications.

Research progress on the prevention and treatment of hyperuricemia by medicinal and edible plants and its bioactive components

Hyperuricemia is another common metabolic disease, which is considered to be closely related to the development of many chronic diseases, in addition to the "three highs." Currently, although drugs show positive therapeutic effects, they have been shown to produce side effects that can damage the body. There is growing evidence that medicinal and edible plants and their bioactive components have a significant effect on hyperuricemia. In this paper, we review common medicinal and edible plants with uric acid-lowering effects and summarize the uric acid-lowering mechanisms of different bioactive components. Specifically, the bioactive components are divided into five categories: flavonoids, phenolic acids, alkaloids, polysaccharides, and saponins. These active substances exhibit positive uric acid-lowering effects by inhibiting uric acid production, promoting uric acid excretion, and improving inflammation. Overall, this review examines the potential role of medicinal and edible plants and their bioactive components as a means of combating hyperuricemia, with the hope of providing some reference value for the treatment of hyperuricemia.

A strategy to comprehensively analyze the bioactivity of complex herbal prescriptions via peak-by-peak cutting and knock-out chromatography: Qiliqiangxin capsule as an example

An herbal prescription is usually composed of several herbal medicines. The complex and diverse components bring great challenges to its bioactivity study. To comprehensively analyze the bioactivity of an herbal prescription, a new strategy based on peak-by-peak cutting and knock-out chromatography was proposed. In this strategy, active compounds were screened out via peak-by-peak cutting from an herbal extract, and the influence of a compound on the overall activity of the herbal extract was evaluated by knock-out chromatography. Qiliqiangxin capsule is an herbal prescription composed of 11 herbal medicines for the treatment of chronic heart failure. A total of 71 peaks were collected through peak-by-peak cutting, and each peak was identified by high-resolution mass spectrum. The bioassay against 1,1-diphenyl-2-picrylhydrazyl showed that two types of compounds namely salvianolic acids and caffeoylquinic acids were potent scavengers. Knock-out chromatography suggested that the removement of one single compound had no obvious influence on the overall activity of Qiliqiangxin capsule. After all the main peaks in Qiliqiangxin capsule were knocked out, the remaining part still exhibited a potent activity, indicating a high activity stability of Qiliqiangxin capsule. The proposed strategy is helpful for the comprehensive analysis of the bioactivity of other herbal prescriptions. This article is protected by copyright. All rights reserved.

Bioactive Isolates of Morus Species as Antibacterial Agents and their In Silico Profiling

Background:

The genus Morus is one of the rich sources of phytomedicine and considered a beneficial natural source for drugs with potential antimicrobial effect under the traditional system of medicine.

Introduction:

In the present study, three bioactive compounds isolated from the leaves of two species of genus Morus and their antibacterial effect against selective pathogens were assessed.

Methods:

The inhibitory effects of the three molecules isolated were assessed for their minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) against selected pathogens. The in-silico studies provided the toxicity profile and the binding interactions with glucosamine- 6-phosphate synthase for all the isolates.

Results:

Among the three compounds tested, cathafuran-B showed a prominent bacteriostatic and bactericidal effect, which is supported by the results of in-silico analysis suggesting that cathafuran- B could be a potential glucosamine-6-phosphate synthase inhibitor.

Conclusion:

The biomolecule isolated from less explored Morus laevigata exhibiting higher antibacterial effect among the compounds tested warranted opening a new prospect in phytomedicinal research for exploring its pharmacological properties and lowering the utilization load present on highly explored Morus alba.

Classification-based strategies to simplify complex traditional Chinese medicine (TCM) researches through liquid chromatography-mass spectrometry in the last decade (2011-2020): Theory, technical route and difficulty

The difficulty of traditional Chinese medicine (TCM) researches lies in the complexity of components, metabolites, and bioactivities. For a long time, there has been a lack of connections among the three parts, which is not conducive to the systematic elucidation of TCM effectiveness. To overcome this problem, a classification-based methodology for simplifying TCM researches was refined from literature in the past 10 years (2011-2020). The theoretical basis of this methodology is set theory, and its core concept is classification. Its starting point is that "although TCM may contain hundreds of compounds, the vast majority of these compounds are structurally similar". The methodology is composed by research strategies for components, metabolites and bioactivities of TCM, which are the three main parts of the review. Technical route, key steps and difficulty are introduced in each part. Two perspectives are highlighted in this review: set theory is a theoretical basis for all strategies from a conceptual perspective, and liquid chromatography-mass spectrometry (LC-MS) is a common tool for all strategies from a technical perspective. The significance of these strategies is to simplify complex TCM researches, integrate isolated TCM researches, and build a bridge between traditional medicines and modern medicines. Potential research hotspots in the future, such as discovery of bioactive ingredients from TCM metabolites, are also discussed. The classification-based methodology is a summary of research experience in the past 10 years. We believe it will definitely provide support and reference for the following TCM researches.

Rapid identification of urokinase plasminogen activator inhibitors from Traditional Chinese Medicines based on ultrafiltration, LC-MS and in silico docking

The urokinase plasminogen activator (uPA) is regarded as the crucial trigger for plasmin generation, which is involved in several diseases especially for neoplasm metastasis. In this study, an efficient approach integrating ultrafiltration, LC/MS, bioassay and in silico docking, was proposed for rapidly detecting uPA ligands from Traditional Chinese Medicines (TCMs). Forty-two TCMs were initially assessed, and as illustrative case studies, Galla Chinensis and Sanguisorbae Radix, which appeared significant inhibitory activities on uPA, were chosen to develpe and verify the strategy. A total of seven uPA ligands were successfully detected and identified. Two of them, pentagalloylglucose and 28-O-β-d-glucopyranosyl pomolic acid, were demonstrated to be potential inhibitors, with IC50 at 1.639 μM and 37.82 μM repectively. Furthermore, a combinatorial compound library screening combined with in silico docking assay, was revealed that ursolic acid (IC50 = 2.623 μM) was also speculated to be a potent parent structure for inhibition of uPA. This approach offers a multidimensional perspective to discover uPA-binding leading compounds from TCMs or other complex mixtures, which would provide an efficient route for drug discovery.

28-Day Oral Chronic Toxicity Study of Arctigenin in Rats

Arctium lappa (burdock) is the most popular daily edible vegetable in China and Japan because of its general health tonic effects. Previous studies focused on the beneficial role of Arctigenin but neglected its potential side-effects and toxicities. In the present study, the sub-chronic toxicity profile of Arctigenin following 28 days of consecutive exposure was investigated in rats. The results showed that during the drug exposure period, Arctigenin-12 mg/kg administration resulted in focal necrosis and lymphocytes infiltration of heart ventricular septal muscle cells. In the kidney cortical zone, the renal tubular epithelial cells were swollen, mineralized, and lymphocyte infiltrated. In the liver, the partial hepatocyte cytoplasm showed vacuolation and fatty changes, focal necrosis, and interstitial lymphocyte infiltration. In the rats that underwent 36 mg/kg/day administration, there was bilateral testis and epididymis atrophy. In the lung and primary bronchus, erythrocytes and edema fluid were observed. Changes of proestrus or estrus were observed in the uterus, cervix, and vagina intimal epithelial cells. Lymphocytic focal infiltration occurred in the prostate mesenchyme. The high dosage of Arctigenin only decreased the body weight at day 4. At the end of the recovery period, histopathological changes were irreversible, even after withdrawal of the drug for 28 days. Focal necrosis still existed in the heart ventricular septal muscle cells and hepatocytes. Lymphocyte infiltrations were observed in the heart, renal cortex, hepatocyte, and pancreas exocrine gland. Meanwhile, atrophy occurred in the testicles and pancreas. In addition, in the Arctigenin-12 mg/kg group, creatinine (CREA) and brain weight were both significantly increased. The toxicokinetical study demonstrated that Arctigenin accumulated in the organs of rats. The food consumption, hematological, and biochemical parameters were not associated with the above results. These contradictory results might result from the lesions induced by Arctigenin, which were not sufficiently serious to change the parameters. These results suggest that Arctium lappa should be consumed daily with caution because of the potential toxicity induced by Arctigenin. According to all results, the lowest observed adverse effect level (LOAEL) was induced by 12 mg/kg daily exposure to Arctigenin, and the No-observed-adverse-effect-level (NOAEL) should be lower than 12 mg/kg.

Evaluation of anti-lipase activity and bioactive flavonoids in the Citri Reticulatae Pericarpium from different harvest time

BACKGROUND

Inhibition of pancreatic lipase is an attractive approach to the treatment of obesity and other metabolic disorders. Naturally occurring phytochemicals are promising sources of lipase inhibitors.

PURPOSE

In the present study, the anti-lipase activity of Citri Reticulatae Pericarpium (CRP) extracts was firstly evaluated in vitro. Moreover, the dynamic alteration of bioactive flavonoids in CRP collected at different time and its correlation with anti-lipase activities was investigated.

STUDY DESIGN/METHODS

Quantitative analysis of multi-components by a single-marker (QAMS) method was developed and validated for simultaneous determination of six flavonoids including narirutin, hesperidin, didymin, nobiletin, 3,5,6,7,8,3',4'-heptamethoxyflavone and tangeretin. Anti-lipase activity evaluation and docking studies of the flavonoids was also carried out to screen out the candidate lipase inhibitors.

RESULTS

The QAMS method validation results exhibited that the developed method had desirable specificity, linearity, precision and accuracy. CRP collected in early months contained higher concentrations of bioactive flavonoids, and exhibited more potent anti-lipase activity.

CONCLUSION

Harvest timing had a significant impact on the amounts of bioactive flavonoids and the anti-lipase activities of CRP extracts. The contents of total flavonoids were positively correlated with the anti-lipase activities of CRP, and polymethoxyflavones played a significant role in the hypolipidemic effect of CRP. Nobiletin might be the most potential lipase inhibitor in CRP.