UHPLC-MS/MS method for the simultaneous quantitation of five anthraquinones and gallic acid in rat plasma after oral administration of prepared rhubarb decoction and its application to a pharmacokinetic study in normal and acute blood stasis rats

Historical evolution and processing mechanism of 'nine steaming and nine drying' of traditional Chinese medicine preparation

CONTEXT

Nine steaming and nine drying is a traditional Chinese medicine (TCM) processing method and it is widely used for processing tonifying herbs. Modern research reveals that the repeated steaming and drying process varies the composition and clinical efficacy of TCM.

OBJECTIVE

This paper analyzes and explores the historical evolution, research progress, development strategies, and problems encountered in the nine steaming and nine drying process so as to provide a reasonable explanation for this method.

METHODS

English and Chinese literature from 1986 to 2023 was collected from databases including Web of Science, PubMed, Elsevier, Chinese Pharmacopoeia 2020 (CP), and CNKI (Chinese). Nine steaming and nine drying, processing, TCM and pharmacological activity were used as the key words.

RESULTS

Nine steaming and nine drying has undergone thousands of years of clinical practice. Under specific processing conditions of nine steaming and nine drying, the ingredients of the TCM have significant changes, which in turn altered clinical applications.

CONCLUSIONS

This review provides sufficient evidence to prove the rationality and scientific value of nine steaming and nine drying and puts forward a development direction for future research.

The phytochemistry and pharmacology of three Rheum species: A comprehensive review with future perspectives

BACKGROUND

Rheum palmatum, R. tanguticum, and R. officinale, integral species of the genus Rheum, are widely used across global temperate and subtropical regions. These species are incorporated in functional foods, medicines, and cosmetics, recognized for their substantial bioactive components.

PURPOSE

This review aims to synthesize developments from 2014 to 2023 concerning the botanical characteristics, ethnopharmacology, nutritional values, chemical compositions, pharmacological activities, mechanisms of action, and toxicity of these species.

METHODS

Data on the three Rheum species were gathered from a comprehensive review of peer-reviewed articles, patents, and clinical trials accessed through PubMed, Google Scholar, Web of Science, and CNKI.

RESULTS

The aerial parts are nutritionally rich, providing essential amino acids, fatty acids, and minerals, suitable for use as health foods or supplements. Studies have identified 143 chemical compounds, including anthraquinones, anthrones, flavonoids, and chromones, which contribute to their broad pharmacological properties such as laxative, anti-diarrheal, neuroprotective, hepatoprotective, cardiovascular, antidiabetic, antitumor, anti-inflammatory, antiviral, and antibacterial effects. Notably, the materials science approach has enhanced understanding of their medicinal capabilities through the evaluation of bioactive compounds in different therapeutic contexts.

CONCLUSION

As medicinal and economically significant herb species, Rheum species provide both edible aerial parts and medicinal underground components that offer substantial health benefits. These characteristics present new opportunities for developing nutritional ingredients and therapeutic products, bolstering the food and pharmaceutical industries.

Dietary gallic acid as an antioxidant: A review of its food industry applications, health benefits, bioavailability, nano-delivery systems, and drug interactions

Gallic acid (GA), a dietary phenolic acid with potent antioxidant activity, is widely distributed in edible plants. GA has been applied in the food industry as an antimicrobial agent, food fresh-keeping agent, oil stabilizer, active food wrap material, and food processing stabilizer. GA is a potential dietary supplement due to its health benefits on various functional disorders associated with oxidative stress, including renal, neurological, hepatic, pulmonary, reproductive, and cardiovascular diseases. GA is rapidly absorbed and metabolized after oral administration, resulting in low bioavailability, which is susceptible to various factors, such as intestinal microbiota, transporters, and metabolism of galloyl derivatives. GA exhibits a tendency to distribute primarily to the kidney, liver, heart, and brain. A total of 37 metabolites of GA has been identified, and decarboxylation and dihydroxylation in phase I metabolism and sulfation, glucuronidation, and methylation in phase Ⅱ metabolism are considered the main in vivo biotransformation pathways of GA. Different types of nanocarriers, such as polymeric nanoparticles, dendrimers, and nanodots, have been successfully developed to enhance the health-promoting function of GA by increasing bioavailability. GA may induce drug interactions with conventional drugs, such as hydroxyurea, linagliptin, and diltiazem, due to its inhibitory effects on metabolic enzymes, including cytochrome P450 3A4 and 2D6, and transporters, including P-glycoprotein, breast cancer resistance protein, and organic anion-transporting polypeptide 1B3. In conclusion, in-depth studies of GA on food industry applications, health benefits, bioavailability, nano-delivery systems, and drug interactions have laid the foundation for its comprehensive application as a food additive and dietary supplement.

Effects of Anthraquinones on Immune Responses and Inflammatory Diseases

The anthraquinones (AQs) and derivatives are widely distributed in nature, including plants, fungi, and insects, with effects of anti-inflammation and anti-oxidation, antibacterial and antiviral, anti-osteoporosis, anti-tumor, etc. Inflammation, including acute and chronic, is a comprehensive response to foreign pathogens under a variety of physiological and pathological processes. AQs could attenuate symptoms and tissue damages through anti-inflammatory or immuno-modulatory effects. The review aims to provide a scientific summary of AQs on immune responses under different pathological conditions, such as digestive diseases, respiratory diseases, central nervous system diseases, etc. It is hoped that the present paper will provide ideas for future studies of the immuno-regulatory effect of AQs and the therapeutic potential for drug development and clinical use of AQs and derivatives.

Rheum officinale Baill. Treats zebrafish embryo thrombosis by regulating NOS3 expression in the arginine biosynthesis pathway

BACKGROUND

Rheum officinale Baill. (ROB), as one of the traditional Chinese medicines for promoting blood circulation and removing blood stasis, has a wide range of pharmacological effects, such as cardiovascular protection, and has become a common drug in the clinical care of thrombosis.

OBJECTIVE

Although there are some pharmacological studies on ROB in the treatment of thrombotic diseases, the mechanism and material basis are still unclear. Based on the arginine biosynthesis signalling pathway, this research explored the target proteins and metabolites related to the intervention of ROB in thrombosis and expounded on the antithrombotic mechanism of ROB from the comprehensive perspectives of target prediction, intermediate metabolites and potential metabolic pathways.

METHODS

In this research, ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) technology was used to qualitatively detect the chemical compounds of ROB, and the antithrombotic activity of ROB was evaluated by establishing a zebrafish model. The target function was predicted by network pharmacology, and differential metabolites were screened by metabolomics and multivariate statistical analysis methods. Correlation analysis of network pharmacology and metabolomics screening results was conducted to identify the potential pathway of ROB intervention in thrombosis, and the prediction results were further verified.

RESULTS

ROB significantly reduced the reactive oxygen species (ROS) staining intensity in zebrafish induced by phenylhydrazine (PHZ) and improved the inhibition rate of thrombosis. By constructing the "herb-disease-component-target" network, it was concluded that the active ingredients of ROB in treating thrombosis involved emodin, aloe-emodin and physcion, and the key targets included nitric oxide synthase 2 (NOS2) and nitric oxide synthase 3 (NOS3). A total of 341 differential metabolites in zebrafish with thrombosis were screened by partial least squares discriminant analysis (PLS-DA). The results of reverse transcription-polymerase chain reaction (RT-PCR) experiments and targeted metabolomics verification showed that ROB was mainly involved in improving thrombosis by upregulating the expression of NOS3 mRNA and regulating the levels of arginine, glutamate and glutamine in the arginine biosynthesis pathway.

CONCLUSIONS

ROB improved thrombosis by regulating the expression of NOS3 mRNA and the contents of arginine, glutamate and glutamine in the arginine biosynthesis signalling pathway.

Fuzzy identification of bioactive components for different efficacies of rhubarb by the back propagation neural network association analysis of UPLC-Q-TOF/MSE and integrated effects

Background

Rhei Radix et Rhizoma (rhubarb), as one of the typical representatives of multi-effect traditional Chinese medicines (TCMs), has been utilized in the treatment of various diseases due to its multicomponent nature. However, there are few systematic investigations for the corresponding effect of individual components in rhubarb. Hence, we aimed to develop a novel strategy to fuzzily identify bioactive components for different efficacies of rhubarb by the back propagation (BP) neural network association analysis of ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry for every data (UPLC-Q-TOF/MS^E) and integrated effects.

Methods

Through applying the fuzzy chemical identification, most components of rhubarb were classified into different chemical groups. Meanwhile the integration effect values of different efficacies can be determined by animal experiment evaluation and multi-attribute comprehensive indexes. Then the BP neural network was employed for association analysis of components and different efficacies by correlating the component contents determined from UPLC-Q-TOF/MS^E profiling and the integration effect values. Finally, the effect contribution of one type of components may be totaled to demonstrate the universal and individual characters for different efficacies of rhubarb.

Results

It suggested that combined anthraquinones, flavanols and their polymers may be the universal character to the multi-functional properties of rhubarb. Other components contributed to the individuality of rhubarb efficacies, including stilbene glycosides, anthranones and their dimers, free anthraquinones, chromones, gallic acid and gallotannins, butyrylbenzenes and their glycosides.

Conclusions

Our findings demonstrated that the bioactive components for different efficacies of rhubarb were not exactly the same and can be systematically differentiated by the network-oriented strategy. These efforts will advance our knowledge and understanding of the bioactive components in rhubarb and provide scientific evidence to support the expansion of its use in clinical applications and the further development of some products based on this medicinal herb.

Supplementary information

The online version contains supplementary material available at 10.1186/s13020-022-00612-9.

Comparison of Three Species of Rhubarb in Inhibiting Vascular Endothelial Injury via Regulation of PI3K/AKT/NF-κB Signaling Pathway

Background/Aim

Rhubarb, a traditional Chinese medicine derived from three species, is commonly used in the prescriptions for promoting blood circulation and removing blood stasis based on its traditional effects of removing blood stasis and dredging the meridians. It has been reported that rhubarb can protect blood vessels by reducing inflammation and inhibiting vascular endothelial injury (VEI), but the effective components and mechanism of rhubarb inhibiting VEI are still unclear. This study aimed to compare the differences in chemical compositions of the three species of rhubarb and their inhibitory effect on VEI, so as to explain the material basis and select the dominant species to inhibit VEI, and to elucidate the mechanism of rhubarb's inhibitory effect on VEI.

Methods

Plant metabolomics was used to compare the chemical components of three species of rhubarb. The efficacy of three species of rhubarb in inhibiting VEI was compared through cell experiments in vitro. At the same time, combined with network pharmacology and molecular docking, the effective components and pathways of rhubarb involved in inhibiting VEI were screened. The mechanism of rhubarb inhibiting VEI was verified by molecular biology.

Results

There were significant differences in the distribution of chemical components among the three species of rhubarb. We identified 36 different chemical components in the positive ion mode and 38 different chemical components in the negative ion mode. Subsequently, the results showed significant differences in inhibiting VEI among the three species of rhubarb based on the contents of inflammatory factors (such as IL-1β, IL-6, and TNF-α), ROS, and NO and confirmed that R. tanguticum had the best inhibitory effect on VEI in the light of the comprehensive efficacy, compared with R. palmatum and R. officinale. Three species of rhubarb alleviated the inflammatory response in LPS-induced EA.hy926 cells by reducing the contents of inflammatory cytokines IL-6, IL-1β, and TNF-α and decreasing expressions of PI3K, AKT, NF-κB p65, and STAT3 protein in the PI3K/AKT/NF-κB pathway and the inhibition of proteins phosphorylation. In addition, three species of rhubarb could lessen the contents of ROS and NO in EA.hy926 cells induced by LPS. All results indicated that the process of inflammation-induced cellular oxidative stress, which resulted in VEI, was obviously improved by three species of rhubarb.

Conclusion

R. tanguticum was more effective among three species of rhubarb, and it had been proved that gallic acid, gallic-acid-O-galloyl-glucoside, procyanidin B-2,3,3′-di-O-gallatein, and other potential components could reduce the contents of inflammatory factors (such as IL-1β, IL-6, and TNF-α), ROS, and NO by inhibiting the PI3K/AKT/NF-κB signaling pathway and protected the vascular endothelium and the blood vessels by improving the inflammation and oxidative stress reaction.

Simultaneous quantification of anthraquinone glycosides, aglycones, and glucuronic acid metabolites in rat plasma and tissues after oral administration of raw and steamed rhubarb in blood stasis rats by UHPLC-MS/MS

Rhubarb is a widely used herbal medicine. To achieve different effects, rhubarb is usually steamed with rice wine (steamed rhubarb). This steaming treatment increases the blood-activating and stasis-removing effects of rhubarb. A specific and accurate ultra high performance liquid chromatography with tandem mass spectrometry method was established for simultaneous determination of anthraquinone glycosides, aglycones, and glucuronic acid metabolites in plasma and tissues after administration of raw rhubarb and steamed rhubarb in blood stasis rats. Chromatographic separation was performed on ACQUITY UPLC BEH Shield RP 18 column using the mobile phase consisting of water and acetonitrile both containing 0.1% formic acid. Satisfactory linearity, precision, accuracy, extraction recovery, and matrix effect have been achieved. From pharmacokinetic study, it showed that glucuronic acid metabolites were found abundantly in plasma as bioactive components. The lower area under concentration-time curve, maximum concentration, and higher apparent volume of distribution (P < 0.01), body clearance (P < 0.01) values in steamed rhubarb showed that most components of steamed rhubarb have lower bioavailability in plasma compared with raw rhubarb. But it found these components were mainly distributed in spleen and liver with large blood flow and perfusion rates. The pharmacokinetics and tissue distribution studies of anthraquinone components will provide helpful information for clinical application of steamed rhubarb and raw rhubarb.

Pharmacokinetics, tissue distribution and excretion of five rhubarb anthraquinones in rats after oral administration of effective fraction of anthraquinones from rheum officinale

Rhubarb, a famous traditional Chinese medicine, shows a wide range of physiological activities and pharmacological benefits. Rhubarb anthraquinones are perceived as the pharmacologically active compounds of Rhubarb, and understanding metabolism of them is crucial to assure safety and effectiveness of clinical application. In this study, the pharmacokinetics, tissue distribution and excretion of five rhubarb anthraquinones (aloe-emodin, rhein, emodin, chrysophanol, physcion) were systematically investigated after oral administration of rhubarb extract to rats.An HPLC method was developed and validated for quantitation of five rhubarb anthraquinones in rat plasma, tissues, urine and faeces to investigate the Pharmacokinetic characteristics. The results showed that the proposed method was suitable for the quantification of five anthraquinones in plasma, tissue and excreta samples with satisfactory linear (r > 0.99), precision (<10%) and recovery (85.12-104.20%). The plasma concentration profiles showed a quick absorption with the mean T_max of 0.42-0.75 h and t_1/2 of 6.60-15.11 h for five anthraquinones. The analytes were widely distributed in most of the tissues. Approximately 0.13-10.59% and 28.47-81.14% of five anthraquinones were recovered in urine and faeces within 132 h post-dosing, which indicated the major elimination route was faeces excretion.In summary, this study lays a foundation for elucidating the pharmacokinetic rule of rhubarb anthraquinone and the important data can provide reliable scientific resource for further research.

Pharmacokinetics of Anthraquinones from Medicinal Plants

Anthraquinones are bioactive natural products, some of which are active components in medicinal medicines, especially Chinese medicines. These compounds exert actions including purgation, anti-inflammation, immunoregulation, antihyperlipidemia, and anticancer effects. This study aimed to review the pharmacokinetics (PKs) of anthraquinones, which are importantly associated with their pharmacological and toxicological effects. Anthraquinones are absorbed mainly in intestines. The absorption rates of free anthraquinones are faster than those of their conjugated glycosides because of the higher liposolubility. A fluctuation in blood concentration and two absorption peaks of anthraquinones may result from the hepato-intestinal circulation, reabsorption, and transformation. Anthraquinones are widely distributed throughout the body, mainly in blood-flow rich organs and tissues, such as blood, intestines, stomach, liver, lung, kidney, and fat. The metabolic pathways of anthraquinones are hydrolysis, glycuronidation, sulfation, methylation/demethylation, hydroxylation/dehydroxylation, oxidation/reduction (hydrogenation), acetylation and esterification by intestinal flora and liver metabolic enzymes, among which hydrolysis, glycuronidation and sulfation are dominant. Of note, anthraquinones can be transformed into each other. The main excretion routes for anthraquinones are the kidney, recta, and gallbladder. Conclusion: Some anthraquinones and their glycosides, such as aloe-emodin, chrysophanol, emodin, physcion, rhein and sennosides, have attracted the most PK research interest due to their more biological activities and/or detectability. Anthraquinones are mainly absorbed in the intestines and are mostly distributed in blood flow-rich tissues and organs. Transformation into another anthraquinone may increase the blood concentration of the latter, leading to an increased pharmacological and/or toxicological effect. Drug-drug interactions influencing PK may provide insights into drug compatibility theory to enhance or reduce pharmacological/toxicological effects in Chinese medicine formulae and deserve deep investigation.

Exploration in the mechanism of rhubarb for the treatment of hyperviscosity syndrome based on network pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Hyperviscosity syndrome (HVS) is a major risk factor for thrombotic diseases. Rhubarb, well-known as a traditional Chinese medicine, exhibits multiple pharmacological activities, especially for promoting blood circulation to remove blood stasis (PBRB), which has been become a functional health food for decreasing the risk of cardiovascular diseases. However, due to the complexity of rhubarb components, it is still difficult to clarify the specific targets of effective substances in PBRB, and the pharmacodynamic mechanism needs to be further probed.

MATERIALS AND METHODS

The "compound-target-cell-disease" network analysis was initially used to predict potential targets and bioactive compounds. The effect of rhubarb for the treatment of HVS was examined by histopathology and biochemical assays based on the HVS rat model.

RESULTS

Through the "compound-target-cell-disease" network analysis, eight potential therapeutic targets were eventually screened out, and platelets were predicted as the main effector cells of rhubarb in PBRB. Among targets coagulation factor II (prothrombin, F2) and fibrinogen gamma chain (FGG) were closely related to platelets, and five compounds associated with F2 and FGG were predicted including emodin-8-O-beta-D-glucopyranoside (Emo), physcion-8-O-beta-D-glucopyranoside (Phy), procyanidin B-5,3'-O-gallate, torachrysone-8-O-beta-D-(6'-oxayl)-glucoside and epicatechin. Furthermore, thoracic aorta histopathology and biochemical examinations showed middle dose of rhubarb (0.42 g/kg/day) significantly ameliorated pathological changes, hemorheology parameters, as well as levels of representative biomarkers such as plasma P-selectin (P-sel) and thromboxane (TXB2) in platelet activation compared to HVS rat model, whose effects were comparable to the positive drug aspirin or even better. Finally, it was further validated F2 and FGG as the major effective targets of rhubarb as well as its two active ingredients Emo and Phy in PBRB.

CONCLUSIONS

This study may provide an innovative way and scientific information to further understand the main effective components of rhubarb and its mechanisms about targets of F2 and FGG in PBRB, especially the new therapeutic target FGG, which also provide a basis for establishing a quality control for rhubarb by bioassays that could correlate the clinical efficacy and its mechanism.

The Current Application of LC-MS/MS in Pharmacokinetics of Traditional Chinese Medicines (Recent Three Years): A Systematic Review

BACKGROUND

With significant clinical effects, traditional Chinese medicine (TCM) has been attracting increasing interest of the world's scientific community. However, TCM contains immense amounts of chemical components. It is a great challenge to objectively evaluate the correlation between the in vivo process and the therapeutic effect of TCM. The purpose of this systematic review was to summarize the recent investigation (from 2017 to 2019) on preclinical pharmacokinetics (PK) of TCM via liquid chromatography coupled with mass spectrometry (LC-MS/MS).

METHODS

We reviewed the published articles regarding the PK of TCM by LC-MS/MS. In addition, we summarized information on PK parameter of bioactive components, single herb and traditional Chinese medicine prescriptions.

RESULTS

The vast majority of literature on preclinical PK of TCM uses single oral administration, the biological matrix is mostly rat plasma, and the main PK parameters include AUC, Cmax, Tmax and T1/2, etc. Conclusion: Although LC-MS/MS can be used for high-throughput analysis, the characterization of in vivo processes of TCM still has a long way. With the advantages of high sensitivity, high specificity and simple operation, the increasingly mature LC-MS/MS technology will play an important role in the PK study of TCM.

A sensitive ultra-fast liquid chromatography with tandem mass spectrometry method for simultaneous determination of ten constituents of Deng-Zhan-Xi-Xin injection in rat plasma and its application to a comparative pharmacokinetic study in sham and middle cerebral artery occlusion rats

Deng-Zhan-Xi-Xin injection is widely used to treat cerebrovascular and cardiovascular diseases in clinical practice. A rapid and selective method based on ultra-fast liquid chromatography with tandem mass spectrometry was established and validated to simultaneously quantify chlorogenic acid, 1,3-O-dicaffeoylquinic acid, isochlorogenic acid A, neochlorogenic acid, erigeside I, cryptochlorogenic acid, apigenin-7-O-glucuronide, scutellarin, isochlorogenic acid B, and isochlorogenic acid C of Deng-Zhan-Xi-Xin injection in both sham and middle cerebral artery occlusion rats. This was the first quantitative analysis of these ten constituents in both sham and middle cerebral artery occlusion rats. Chromatographic separation of these ten constituents was accomplished on an Acquity HSS T3 column with the mobile phase consisting of acetonitrile and 0.1% formic acid in water. Mass analysis was performed in negative ion mode with an electrospray ionization source using multiple reaction monitoring technology. The pharmacokinetic study of the ten constituents in sham and middle cerebral artery occlusion rats after intravenous administration of Deng-Zhan-Xi-Xin injection was successfully accomplished by using this validated method. Based on the results of pharmacokinetic parameters, significant differences were observed between the two groups, which might be due to the pathological factors of middle cerebral artery occlusion and pharmacological effects of Deng-Zhan-Xi-Xin injection.

Facile synthesis and immobilization of boroxine polymers containing carbon chains and their application as adsorbents

Novel boroxine-linked covalent organic polymers was synthesized and immobilized by one pot reaction for extraction of anthraquinones.

Pharmacokinetics of 13 active components in a rat model of middle cerebral artery occlusion after intravenous injection of Radix Salviae miltiorrhizae-Lignum dalbergiae odoriferae prescription

As a representative formulation of Radix Salviae miltiorrhizae (Danshen)-Lignum Dalbergiae odoriferae (Jiangxiang), Xiangdan injection is widely prescribed for cardio- and cerebrovascular diseases in practice. This necessitates a pharmacokinetic investigation of this formulation to make it safer and more broadly applicable. We developed and validated a sensitive, selective, and reliable high-performance liquid chromatography with tandem mass spectrometry method for the simultaneous determination of 11 phenolic compounds including danshensu plus two diterpenoid quinones like cryptotanshinone and tanshinone IIA in rat. We applied this method for the pharmacokinetic studies of the 13 compounds in a rat model of middle cerebral artery occlusion after intravenous injection of Xiangdan injection or Danshen injection. In sham-operated rats, the animals taking Xiangdan injection exhibited significant growth of the area under the curve for danshensu, protocatechuic aldehyde, and tanshinone IIA compared with the changes seen in the data of those administrated with Danshen injection. Such a pattern was also observed in middle cerebral artery occlusion rats, whereas increased the area under the curve values were observed for danshensu, protocatechuic aldehyde, caffeic acid, rosmarinic acid, and tanshinone IIA. These results demonstrated that synergistic interactions occurred between the components of Danshen and the active compounds of Jiangxiang both in sham-operated and middle cerebral artery occlusion rats, increasing the bioavailability of Danshen. The results presented herein can be used to determine a reference dose for the clinical application of Xiangdan injection, and to elucidate the synergistic mechanism of Danshen and Jiangxiang.

Yinang formulation versus placebo granules as a treatment for chronic kidney disease stages III-IV in patients with autosomal dominant polycystic kidney disease: study protocol for a double-blind placebo-controlled randomized clinical trial

BACKGROUND

Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common potentially life-threatening inherited kidney diseases. It is the fourth most common cause of end-stage renal disease requiring renal replacement therapy. There are few management options for controlling disease progression. Hence, identification of alternative treatments for patients is important. The Chinese herbal yinang formulation (YNF), which is derived from a Chinese patent medicine, appears to have a satisfactory effect in treating ADPKD. Because a considerable proportion of ADPKD patients presenting with chronic kidney disease (CKD) stages III-IV are diagnosed with the spleen, kidney deficiency, and blood stasis syndrome according to the diagnostic criteria of traditional Chinese medicine (TCM), we hypothesize that YNF may be a complementary drug for ADPKD patients with the corresponding syndrome. Therefore, we have designed a strict clinical trial to evaluate the safety and efficacy of YNF for ADPKD patients with CKD stages III-IV exhibiting the TCM syndrome of spleen, kidney deficiency, and blood stasis.

METHODS/DESIGN

This is a multi-center prospective double-blind randomized controlled trial. The total target sample size is planned to be 72 participants, with a balanced treatment allocation (1:1). The experimental intervention will be YNF plus conventional therapy and the control intervention will be a placebo plus conventional therapy for 24 weeks. An additional 24 weeks of follow-up will be conducted after treatment completion. The primary outcome will be the estimated glomerular filtration rate (eGFR). Changes in total kidney volume (TKV), serum creatinine (Scr), blood urea nitrogen (BUN), TCM symptoms, and pain will be the secondary outcomes. Adverse events (AEs) will be monitored throughout the trial.

DISCUSSION

This study will be the first placebo-controlled randomized controlled trial to assess whether YNF plus conventional therapy has a beneficial effect on eGFR, TKV, Scr, and BUN, and whether it can alleviate TCM clinical symptoms, reduce ADPKD-related pain, and reduce the frequency of AEs for ADPKD patients with CKD stages III-IV with the spleen, kidney deficiency, and blood stasis syndrome. The results of this trial may provide an evidence-based recommendation for clinicians.

TRIAL REGISTRATION

Chinese Clinical Trials Register, ChiCTR-INR-16009914 . Registered on 18 November 2016.

Pharmacokinetics and Tissue Distribution Study of Pinosylvin in Rats by Ultra-High-Performance Liquid Chromatography Coupled with Linear Trap Quadrupole Orbitrap Mass Spectrometry

Pinosylvin is a potential anti-inflammatory and antioxidant compound and the major effective medicinal ingredient in the root of Lindera reflexa Hemsl. However, few investigations have been conducted regarding the pharmacokinetics, excretion, characteristics of tissue distribution, and major metabolites of pinosylvin in rats after oral administration. To better understand the behavior and mechanisms of action underlying the activity of pinosylvin in vivo, we established a simple, sensitive, and reliable ultra-high-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method for quantifying pinosylvin in rat plasma, urine, feces, and various tissues (including heart, liver, spleen, lung, kidneys, large intestine, small intestine, and stomach). Noncompartmental pharmacokinetic parameters indicated that pinosylvin is rapidly distributed and taken up by tissues. The time to peak (maximum) concentration (T_max) was 0.137 h, and the apparent elimination half-life (t_1/2) was 1.347±0.01 h. The results of the tissue distribution study suggest that pinosylvin is widely distributed to various tissues; the highest concentration was observed after 10 min in the stomach, followed by the heart, lung, spleen, and kidneys. Results of the excretion study suggest that a small amount of pinosylvin is excreted from the urine and feces in the parent form; the 73 h accumulative excretion ratios of urine and feces were 0.82% and 0.11%, respectively. It is likely that pinosylvin is mostly metabolized in vivo. Nine metabolites were found, and the main metabolic pathways of pinosylvin in rats included glucuronidation, hydroxylation, and methylation. Four metabolites had higher concentrations in the stomach, suggesting that the stomach is a potential target organ of pinosylvin. In conclusion, the present study may provide a material basis for studying the pharmacological action of pinosylvin and provides meaningful information for the clinical treatment of chronic gastritis and gastric ulcers using Radix Linderae Reflexae.

Simultaneous qualitative and quantitative analysis of 11 active compounds in rhubarb using two reference substances by UHPLC

Multi-component analysis is one of the key techniques for the overall quality control of traditional Chinese medicines. However, the shortage and high cost of reference substances are the greatest obstacles. The substitute method is an alternative solution. In the present study, 11 compounds of rhubarb were simultaneously determined by a method named "two reference substances for determination of multiple components", which includes a qualitative method with linear calibration using two reference substances and a quantitative method with a relative correction factor combined with ultra high performance liquid chromatography. Using aloe-emodin-8-O-β-D-glucopyranoside and chrysophanol as reference compounds, chromatographic peak identification was performed. The results demonstrated that linear calibration using two reference substances method showed higher accuracy, less deviation, and better column adaptability compared to the relative retention time method. Using chrysophanol as a reference compound, the relative correction factors were determined and showed good reproducibility and stability in different laboratories with different instruments, columns, and wavelength fluctuations. The results had no significant difference compared with the external standard method. The strategy of two reference substances for determination of multiple components coupled with ultra high performance liquid chromatography is economical, efficient, accurate, reliable, and environmentally friendly and is suitable for the quality control of traditional Chinese medicines.

iTRAQ-Based Proteomics Analysis Reveals the Effect of Rhubarb in Rats with Ischemic Stroke

Background. Rhubarb, a traditional Chinese medicine, promotes viscera and remove blood stasis. Rhubarb is skilled in smoothening meridians, improving blood circulation which exhibits better efficacy on cerebral ischemic stroke. In this study, we aimed to analyze the underlying mechanisms of rhubarb which treated rats of middle cerebral artery occlusion (MCAO) model according to an iTRAQ-based proteomics and bioinformatics analysis. 30 rats were randomly allocated into three groups including sham group (SG), model group (MG), and rhubarb group (RG). Rhubarb group was given a gavage of rhubarb decoction at dose of 3 g/kg and the remaining groups were prepared with normal saline by gavage. Rats from MG and RG were induced into MCAO model. The effects of rhubarb were estimated by Modified Neurological Severity Score (mNSS) and cerebral infarct volume. The brain tissues were measured via the quantitative proteomic approach of iTRAQ coupled to liquid chromatography-tandem mass spectrometry (LC-MS/MS). Furthermore, the bioinformatics analysis of overlapping differentially expression proteins (DEPs) was conducted by DAVID, KEGG, and Cytoscape. Specific selective DEPs were validated by Western blotting. Rats treated with rhubarb after MCAO showed a significant reduction on mNSS and cerebral infarct volume compared with MG. In MG versus SG and RG versus MG, we identified a total of 4578 proteins, of which 287 were DEPs. There were 76 overlapping DEPs between MG versus SG and RG versus MG. Through bioinformatics analysis, 14 associated pathways were searched including cGMP-PKG signaling pathway, tuberculosis, synaptic vesicle cycle, amyotrophic lateral sclerosis, long-term potentiation, and so on. 76 overlapping DEPs mainly involved synaptic vesicle cycling biological processes based on GO annotation. Further, the selective overlapping DEPs were verified at the protein level by using Western blotting. Our present study reveals that rhubarb highlights promising neuroprotective effect. Rhubarb exerts novel therapeutic action via modulating multiple proteins, targets, and pathways.

Comparative Pharmacokinetics of Gallic Acid After Oral Administration of Gallic Acid Monohydrate in Normal and Isoproterenol-Induced Myocardial Infarcted Rats

Gallic acid (GA) is a polyphenolic natural product widely distributed in food, beverage, and traditional Chinese herbs with beneficial effects on the cardiovascular system. In this research, a comparative study was conducted to investigate the possible difference of pharmacokinetic process in normal and isoproterenol-induced myocardial infarcted rats after oral administration of GA monohydrate with the dose of 50 and 100 mg/kg, respectively. Quantification of GA in rat plasma was achieved by using a simple and rapid high-performance liquid chromatographic method. The results revealed that pharmacokinetics of GA were greatly different between normal and pathological state. GA exhibited slower absorption into the bloodstream, and yielded 1.7-fold (50 mg/kg GA) and 1.3-fold (100 mg/kg GA) less values of area under concentration-time curve as well as 2.5-fold lower of maximum blood concentration (C_max) in MI rats than those in normal rats. In addition, significant prolonged T_1/2 and MRT as well as decreased CL were also registered in MI rats. Our findings suggest that myocardial infarction could alter the pharmacokinetic process of GA, and thus the potential pharmacokinetic differences of herbal preparations (or dietary nutrition) containing GA between normal and pathological conditions should be brought to the forefront seriously in clinical practice.