Determination and pharmacokinetic comparison of rhein in rats after oral dosed with Da-Cheng-Qi decoction and Xiao-Cheng-Qi decoction

Integrated pharmacokinetic properties and tissue distribution of multiple active constituents in Qing-Yi Recipe: A comparison between granules and decoction

BACKGROUND

Qing-Yi Recipe, a classic traditional Chinese medicine (TCM), is widely used for treating acute diseases of the abdomen, especially pancreatitis, the efficacy of which has been demonstrated in more than thirty clinical trials. However, the in-vivo pharmacodynamic material basis for this formula remains unclear.

METHODS

A sensitive and accurate method for quantifying twenty-two potential bioactive constituents of Qing-Yi Recipe in biological samples was developed using liquid chromatography-tandem mass spectrometry (LC-MS/MS), and this method was fully validated. Then, the integrated pharmacokinetic properties of Qing-Yi Recipe and its major metabolites in rats were investigated using the post-listed granules at both dosages. Subsequently, tissue distributions of those constituents in nine organs (especially the pancreas) were determined, and the overall parameters between the two formulations were compared.

RESULTS

Though the chemical profiles of the formulas varied across formulations, the overall exposure level was very similar, and baicalin, wogonoside, geniposide, rhein, costunolide, and paeoniflorin were the top six bioactive compounds in the circulation. All twenty-two natural products reached their first peak within 2 h, and several of them exhibited bimodal or multimodal patterns under the complicated transformation of metabolic enzymes, and the parameters of these products markedly changed compared with those of monomers. Diverse metabolites of emodin and baicalin/baicalein were detected in circulation and tissues, augmenting the in vivo forms of these compounds. Finally, the enrichment of tetrahydropalmatine and corydaline in the pancreas were observed and most compounds remained in the gastrointestinal system, providing a foundation basis for their potential regulatory effects on the gut microbiota as well as the intestinal functions.

CONCLUSION

Herein, the pharmacokinetic properties and tissue distribution of multiple potential active constituents in Qing-Yi Recipe were investigated at two dosages, providing a pharmacodynamic material basis of Qing-Yi Recipe for the first time. This investigation is expected to provide a new perspective and reference for future studies on the physiological disposition and potential pharmacodynamic basis of traditional Chinese medicine to treat acute abdomen diseases.

A Review on Bioactive Anthraquinone and Derivatives as the Regulators for ROS

Anthraquinones are bioactive natural products, which are often found in medicinal herbs. These compounds exert antioxidant-related pharmacological actions including neuroprotective effects, anti-inflammation, anticancer, hepatoprotective effects and anti-aging, etc. Considering the benefits from their pharmacological use, recently, there was an upsurge in the development and utilization of anthraquinones as reactive oxygen species (ROS) regulators. In this review, a deep discussion was carried out on their antioxidant activities and the structure-activity relationships. The antioxidant mechanisms and the chemistry behind the antioxidant activities of both natural and synthesized compounds were furtherly explored and demonstrated. Due to the specific chemical activity of ROS, antioxidants are essential for human health. Therefore, the development of reagents that regulate the imbalance between ROS formation and elimination should be more extensive and rational, and the exploration of antioxidant mechanisms of anthraquinones may provide new therapeutic tools and ideas for various diseases mediated by ROS.

Quinones: Biosynthesis, Characterization of 13 C Spectroscopical Data and Pharmacological Activities

Quinones are natural products widely distributed in nature, which are involved in stages of several vital biological processes, with mostly having a variety of pharmacological properties. The main groups comprising most of these compounds are benzoquinones, naphthoquinones, anthraquinones, and phenanthraquinones. Quinone isolation has been a focus of study around the world in recent years; for this reason, this study approaches the junction of natural quinones identified by 13 C Nuclear Magnetic Resonance (NMR) spectroscopic analytical techniques. The methodology used to obtain the data collected articles from various databases on quinones from 2000 to 2022. As a result, 137 compounds were selected, among which 70 were characterized for the first time in the period investigated; moreover, the study also discusses the biosynthetic pathways of quinones and the pharmacological activities of the compounds found, giving an overview of the various applications of these compounds.

RP-HPLC METHOD DEVELOPMENT, VALIDATION, AND ITS PHARMACOKINETIC APPLICABILITY IN PRECLINICAL EVALUATION OF RHEIN TREATED WITH NOVEL DIACEREIN EUTECTICS

The current study represents the bio-analytical method for the estimation of Rhein (Rh, an active metabolite of Diacerein (DIA)) in rats treated with novel DIA eutectics to investigate the pharmacokinetics of DIA. A simple protein precipitation technique was used to extract Rh and internal standard (IS), p-aminobenzoic acid, and injected into a Phenomenex Gemini C18 column. The separation was achieved by gradient elution comprising of ammonium acetate (10 mM; pH 3.0) and acetonitrile in 18 min of run time at a flow rate of 0.8 mL/min with the retention time of 11.8 min (Rh) and 5.9 min (IS). The results revealed that the proposed method was linear over the range of 200-20,000 ng/mL (r² > 0.9988) of Rh and proved to be precise and accurate. The method was fully validated as per the USFDA guideline and the pharmacokinetic study in rats was performed for Rh following oral administration of the pure DIA and newly developed eutectics. Therefore, the present method could be used to estimate DIA to illustrate the comparative pharmacokinetic analysis. This can be also applied to its related multi-component formulations for future study.

The Metabolism and Pharmacokinetics of Rhein and Aurantio-Obtusin

BACKGROUND

Anthraquinones, rhein and aurantio-obtusin were isolated from the herb Duhaldea nervosa for the first time by our group, which were also found in plants that belong to the plant family Compositae. Anthraquinone compounds have a range of pharmacological activities such as anti-inflammatory, anti-cancer, antioxidation, anti-diabetes, etc. and can be used as a laxative, for liver protection, treatment of chronic renal failure, etc. However, in recent years, anthraquinones have been reported to be cytotoxic to the liver and kidneys. Therefore, it is very important to study the pharmacokinetics and metabolism of rhein and aurantio-obtusin, which are common ingredients in many traditional Chinese medicines (TCM). According to our research, the pharmacokinetics and metabolism of rhein and aurantio-obtusin are comprehensively summarized in the paper for the first time.

OBJECTIVE

The study provides comprehensive information on pharmacokinetics and metabolism of rhein and aurantio- obtusin in different Species; meanwhile, the aim of this review is also to provide a reference for a reasonable application of TCM enriched with these two ingredients.

METHODS

The metabolism and pharmacokinetics of rhein and aurantio-obtusin were searched by the Web of Science, PubMed, Google scholar and some Chinese literature databases.

RESULTS

Rhein and aurantio-obtusin exist mainly in the form of metabolites in the body. Rhein and aurantio-obtusin and its metabolites might be responsible for pharmacological effects in the body. Therefore, the significance of studying the in vivo metabolites of rhein and aurantio-obtusin is not only essential to clarify their pharmacological mechanism, but also to find new active compound ingredients. The metabolism of rhein is different in different species, so the toxicity effects of rhein may also be different after oral administration in different species; however, the metabolic profiles of aurantio-obtusin in the liver microsomes of different species are similar.

CONCLUSION

This paper not only provides detail regarding the pharmacokinetics of rhein and aurantio-obtusin, but it is anticipated that it will also facilitate further study on the metabolism of rhein and aurantio-obtusin.

Optimal timing for the oral administration of Da-Cheng-Qi decoction based on the pharmacokinetic and pharmacodynamic targeting of the pancreas in rats with acute pancreatitis

AIM

To identify the optimal oral dosing time of Da-Cheng-Qi decoction (DCQD) in rats with acute pancreatitis (AP) based on the pharmacokinetic and pharmacodynamic parameters.

METHODS

First, 24 male Sprague-Dawley rats were divided into a sham-operated group [NG(a)] and three model groups [4hG(a), 12hG(a) and 24hG(a)]. The NG(a) and model groups were administered DCQD (10 g/kg.BW) intragastrically at 4 h, 4 h, 12 h and 24 h, respectively, after AP models induced by 3% sodium taurocholate. Plasma samples were collected from the tails at 10 min, 20 min, 40 min, 1 h, 2 h, 4 h, 8 h, 12 h and 24 h after a single dosing with DCQD. Plasma and pancreatic tissue concentrations of the major components of DCQD were determined by high-performance liquid chromatography tandem mass spectroscopy. The pharmacokinetic parameters and serum amylase were detected and compared. Second, rats were divided into a sham-operated group [NG(b)] and three treatment groups [4hG(b), 12hG(b) and 24hG(b)] with three corresponding control groups [MG(b)s]. Blood and pancreatic tissues were collected 24 h after a single dosing with DCQD. Serum amylase, inflammatory cytokines and pathological scores of pancreatic tissues were detected and compared.

RESULTS

The concentrations of emodin, naringin, honokiol, naringenin, aloe-emodin, chrysophanol and rheochrysidin in the 12hG(a) group were higher than those in the 4hG(a) group in the pancreatic tissues (P < 0.05). The area under the plasma concentration-time curve from time 0 to the time of the last measurable concentration values (AUC₀→_t) for rhein, chrysophanol, magnolol and naringin in the 12hG(a) group were larger than those in the 4hG(a) or 24hG(a) groups. The 12hG(a) group had a higher C_max than the other two model groups. The IL-10 levels in the 12hG(b) and 24hG(b) groups were higher than in the MG(b)s (96.55 ± 7.84 vs 77.46 ± 7.42, 251.22 ± 16.15 vs 99.72 ± 4.7 respectively, P < 0.05), while in the 24hG(b) group, the IL-10 level was higher than in the other two treatment groups (251.22 ± 16.15 vs 154.41 ± 12.09/96.55 ± 7.84, P < 0.05). The IL-6 levels displayed a decrease in the 4hG(b) and 12hG(b) groups compared to the MG(b)s (89.99 ± 4.61 vs 147.91 ± 4.36, 90.82 ± 5.34 vs 171.44 ± 13.43, P < 0.05).

CONCLUSION

Late-time dosing may have higher concentrations of the most major components of DCQD, with better pharmacokinetics and pharmacodynamics of anti-inflammation than early-time dosing, which showed the late time to be the optimal dosing time of DCQD for AP.

Formula Compatibility Identification of Dachengqi Decoction Based on the Effects of Absorbed Components in Cerulein-Injured Pancreatic AR42J Cells

Objective. To identify the herbal formula compatibility law based on the effects of the absorbed components from DCQD on the cerulein-injured AR42J cells. Methods. AR42J cells were pretreated for 30 min with or without the different concentrations of the absorbed components from DCQD individually or in combination or DCQD and coincubated with cerulein (10 nM) for a further 24 h. Cell viability, lactate dehydrogenase (LDH) release, and the levels of apoptosis and necrosis were measured. Results. Compared to DCQD, the individual or combination components partially protected cerulein-injured AR42J cells by increasing cell viability, reducing LDH release, and promoting apoptosis. Rhein, naringin, and honokiol were the main absorbed components from DCQD in cerulein-induced pancreatitis. Moreover, rhein in combination with naringin and honokiol had synergistic effects in protecting cerulein-injured AR42J cells and was better than the individual or the pairwise combination of the three components. Conclusions. The ten effective components from DCQD may elicit similar protective effects as DCQD on cerulein-induced pancreatitis. The principle of the formula compatibility of DCQD may be identified based on the effects of its absorbed components in cerulein-injured AR42J cells.

[Effects of ranitidine on pharmacokinetics of rhein from Dachengqi Decoction in rats after oral administration]

OBJECTIVE

To explore the effects of ranitidine on pharmacokinetics of rhein in rats after oral administration of Dachengqi Decoction (DCQD), a compound traditional Chinese herbal medicine.

METHODS

Twelve male Sprague-Dawley rats were divided into DCQD group and DCQD plus ranitidine group, and were orally administered with DCQD at a dose of 10 g/kg or DCQD (10 g/kg) combined with ranitidine (150 mg/kg), respectively. Blood samples were gathered after a series of time intervals. Metabolism of rhein was determined with a reversed-phase high-performance liquid chromatography with internal standard of 1, 8-dihydroxyanthraquinone and the data were analyzed with DAS 2.1 program. The pharmacokinetic parameters were compared between the two groups.

RESULTS

The pharmacokinetic parameters of rhein in the DCQD group, including peak concentration (C(max)), area under the plasma concentration-time curve (AUC), distribution phase half-life (t(1/2alpha)), elimination rate constant (K(10)) and central to peripheral transfer rate constant (K(12)), were significantly different to those in the DCQD plus ranitidine group (P<0.05, P<0.01). There were no significant differences in the other parameters between the two groups.

CONCLUSION

Ranitidine can influence the pharmacokinetics of rhein in rats after oral administration of DCQD.

Targeting of diacerein loaded lipid nanoparticles to intra-articular cartilage using chondroitin sulfate as homing carrier for treatment of osteoarthritis in rats

Targeted delivery of antiosteoarthritic drug diacerein to articular tissue could be a major achievement and soluble polysaccharide chondroitin sulfate (ChS) may be a suitable agent for this. Therefore, diacerein loaded solid lipid nanoparticles modified with ChS (ChS-DC-SLN) were prepared for synergistic effect of these agents to combat multidimensional pathology of osteoarthritis (OA). Prepared formulation were of size range 396±2.7nm, showed extended release up to 16h and increased bioavailability of diacerein by 2.8 times. ChS-DC-SLN were evaluated for their effect on histopathology of femoro-tibial joint of rat knee and amount of ChS and rhein (an active metabolite of diacerein) at targeted site. Concentration of rhein was significantly higher in case of ChS-DC-SLN (7.8±1.23μg/ml) than that of drug dispersion (2.9±0.45μg/ml). It can be stated that ChS served as homing to articular cartilage for targeting of drug. Thus, ChS-DC-SLN have great potential to enhance the overall efficacy of treatment for OA.

FROM THE CLINICAL EDITOR

This study demonstrates the feasibility of targeted delivery of diacerein to articular tissue using soluble polysaccharide chondroitin sulfate as the targeting vector. This approach has the potential to significantly increase anti-arthritic drug concentration in joints without leading to systemic toxicity.

Recent developments in the field of the determination of constituents of TCMs in body fluids of animals and human

Although traditional Chinese medicines (TCMs) play important role in drug discovery and human health, the actual value of TCMs has not been fully recognized worldwide due to its complex components and uncontrollable quality. For the modernization and globalization of TCMs, it is important to establish selective, sensitive and feasible analytical methods for determination and quantification of bioactive components of TCMs in body fluids primarily due to the low concentration, the complex nature of the biological matrices, and multi-components and their metabolites present in biological fluids. The present review summarizes the current extraction techniques, chromatographic separation and spectroscopic (especially mass spectrometric) analysis methods and new trends on the analysis of bioactive components and metabolites of TCMs in biological fluids. In addition, the importance of establishment of pharmacokinetics and bioavailability profiles and simultaneous determination of multi-active components in TCMs is discussed to provide proper examples of analytical methods for pharmacological and clinical studies of TCMs.

Effect of formula compatibility on the pharmacokinetics of components from Dachengqi Decoction [See Text] in rats

OBJECTIVE

To investigate the effect of prescription compatibility on the pharmacokinetics of components from Dachengqi Decoction (DCQD, ) in rats.

METHODS

Twenty-four male rats were randomly and equally divided into the DCQD group, Dahuang (Radix et Rhizoma Rhei, Polygonaceae) group, Houpo (Magnolia officinalis Rehd., Magnoliaceae) group, and Zhishi (Fructus Aurantii Immaturus, Rutaceae) group. The blood samples were collected before dosing and subsequently at 10, 15, 20, 30, 45 min, 1, 2, 4, 8, and 12 h following gavage. The levels of aloe-emodin, rhein, emodin, chrysophanol, honokiol, magnolol, hesperidin, and naringin in rat serum were quantified using a liquid chromatography tandem mass spectrometry (LC-MS/MS) method for pharmacokinetic study.

RESULTS

The area under the curve (AUC), mean retention time (MRT), the peak concentration (C(max)) of aloe-emodin, rhein, emodin, and chrysophanol in the DCQD group were significantly different compared with the Dahuang group (P <0.05, respectively). The mean plasma concentration, C(max), and the absorption of Dahuang's component in the DCQD group were obviously lower at each time point than those in the Dahuang group, while the elimination process of Dahuang's component was obviously delayed (P <0.05). Half-lives of aloe-emodin, chrysophanol, and rhein were also extended in the DCQD group (P <0.05, respectively). In the DCQD group, the mean plasma concentration, AUC, C(max) and absorption of honokiol, and magnolol were significantly lower (P <0.01, respectively) at each time point than those in the Houpo group, while the drug distribution half-life time (T(1/2α)), the drug eliminated half-life time (T(1/2β)), MRT, and time of peak concentration (T(max)) were significantly delayed (P <0.05, respectively). Pharmacokinetic parameters of hesperidin and naringin in the Zhishi group were not significantly different as compared with the DCQD group (P >0.05, respectively), while the MRT of naringin was significantly longer.

CONCLUSIONS

The compatibility in Chinese medicine could affect the drug's pharmacokinetics in DCQD, which proves that the prescription compatibility principle of Chinese medicine formulations has its own pharmacokinetic basis.

Amelioration of experimental acute pancreatitis with Dachengqi Decoction via regulation of necrosis-apoptosis switch in the pancreatic acinar cell

Severity of acute pancreatitis contributes to the modality of cell death. Pervious studies have demonstrated that the herb medicine formula “Dachengqi Decoction” (DCQD) could ameliorate the severity of acute pancreatitis. However, the biological mechanisms governing its action of most remain unclear. The role of apoptosis/necrosis switch within acute pancreatitis has attracted much interest, because the induction of apoptosis within injured cells might suppress inflammation and ameliorate the disease. In this study, we used cerulein (10⁻⁸ M)-stimulated AR42J cells as an in vitro model of acute pancreatitis and retrograde perfusion into the biliopancreatic duct of 3.5% sodium taurocholate as an in vivo rat model. After the treatment of DCQD, cell viability, levels of apoptosis and necrosis, reactive oxygen species positive cells, serum amylase, concentration of nitric oxide and inducible nitric oxide syntheses, pancreatic tissue pathological score and inflammatory cell infiltration were tested. Pretreatment with DCQD increased cell viability, induced apoptosis, decreased necrosis and reduced the severity of pancreatitis tissue. Moreover, treatment with DCQD reduced the generation of reactive oxygen species in AR42J cells but increased the concentration of nitric oxide of pancreatitis tissues. Therefore, the regulation of apoptosis/necrosis switch by DCQD might contribute to ameliorating the pancreatic inflammation and pathological damage. Further, the different effect on reactive oxygen species and nitric oxide may play an important role in DCQD-regulated apoptosis/necrosis switch in acute pancreatitis.

Effects of food and gender on the pharmacokinetics of rhein and emodin in rats after oral dosing with Da-Cheng-Qi decoction

Da-Cheng-Qi decoction (DCQD), a traditional Chinese medicine preparation used to treat digestive diseases, is composed of dahuang (Rheum officinale Baill, Polygonaceae), houpu (Magnolia officinalis Rehd., Magnoliaceae), zhishi (Citrus aurantium L, Rutaceae) and mangxiao (sodium sulphate). Rhein and emodin are the major active components of Rheum officinale Baill. To investigate the effects of food and gender on the plasma concentrations of rhein and emodin after oral administration of DCQD, a rapid high-performance liquid chromatographic method was developed and validated. A reversed phase C(18) column (150 × 4.6 mm) and a mobile phase of methanol and 0.2% acetic acid (78:22, v/v) were employed with ultraviolet detection at 254 nm. Feeding was observed to decrease the absorption of rhein and emodin in rats receiving DCQD orally. No evidence for gender-based differences in the pharmacokinetics of rhein was observed. However, the half-life and area under the concentration-time curve for emodin differed significantly between male and female rats. Because food intake and gender are anticipated to influence the pharmacokinetics of DCQD in human subjects, it is recommended that oral doses of DCQD be reduced in fasting subjects and that female patients receive lower oral doses compared with male patients.

Liver targeting effect of vinegar-baked Radix Bupleuri on rhein in rats

Vinegar-baked Radix Bupleuri (VBRB) is usually used to focus other drugs effect on liver in traditional Chinese medicine (TCM). However, no sufficient scientific data are available to support this concept. In this paper, the liver targeting enhancing effect of VBRB on rhein was investigated. 432 of rats were divided into two large groups according to the dose of rhein, low dose group of rhein (LDGR) and high dose group of rhein (HDGR). In each group, the rats were further divided into four subgroups, rhein control and rhein co-administered with three different doses of VBRB peroral. Concentrations of rhein and its metabolite in different tissues were determined by HPLC. Compared to the control group, VBRB significantly increased the distribution of both rhein and its metabolite in liver and meanwhile decreased their distribution in other tissues, indicating a strong liver targeting enhancing effect. This liver targeting effect of VBRB depended on the dose of VBRB and rhein. Low and high dose of VBRB had a more strong effect than medium dose in HDGR; high dose of rhein was more sensitive than low dose of rhein (P<0.05). Rhein existed in two forms after peroral administration in vivo. It was found that the liver targeting effect of VBRB was more remarkable with the native form of rhein compared to its derivative form. The results of this paper demonstrated that co-administration with VBRB is a simple and efficiencient method for liver targeting therapy, and the meridine guide theory of TCM was credible.

Pharmacokinetic Comparison in Rats of Six Bioactive Compounds between Da-Cheng-Qi Decoction and its Parent Herbal Medicines

Da-Cheng-Qi decoction (DCQD) is a purgative compound prescription used in China and East Asia. In this paper, pharmacokinetic differences of six major active components (rhein, emodin, aloe-emodin, magnolol, naringenin and hesperetin) between DCQD and its three constitutional herbal medicines i.e. Radix et Rhizoma Rhei, Cortex Magnoliae officinalis and Fructus Aurantii Immaturus were investigated in rats after oral administration. Plasma samples were analyzed for the quantification of the six active components using validated LC-MS/MS methods. Unpaired Student's t-test was used for statistical comparison. Significant differences ( p<0.05) in the main pharmacokinetic parameters for rhein, emodin, aloe-emodin, magnolol, naringenin and hesperetin were found between DCQD and the decoction of its constitutional single herbal medicines, which demonstrated the presence of drug-drug interactions between these constitutional raw materials of DCQD occurring either in the procedure of decoction or during ADME process.

Effect of severe acute pancreatitis on pharmacokinetics of Da-Cheng-Qi Decoction components

AIM: To investigate the effect of severe acute pancreatitis (SAP) on pharmacokinetics of Da-Cheng-Qi Decoction (DCQD) components in rats.

METHODS: Rats were divided into SAP group and sham-operation group as a control group (n = 6). Rhein, chrysophanol, rheochrysidin, magnolol, hesperidin and naringin in DCQD were quantified in rat serum by high performance liquid chromatography tandem mass spectrometry for studying their pharmacokinetics.

RESULTS: Early absorption of each DCQD component was tended to degrade in SAP group after treatment with DCQD by gavage. The C_max (chrysophanol, P = 0.0059; rheochrysidin, P = 0.0288; magnolol, P = 0.0487; hesperidin, P = 0.0277; naringin, P = 0.0023) and AUC (rhein, P = 0.0186; chrysophanol, P = 0.0013; magnolol, P = 0.001; hesperidin, P = 0.0081; naringin, P = 0.0272) of DCQD component were obviously lower in SAP group than in control group. The T_1/2α of chrysophanol and rheochrysidin (P = 0.0467 and 0.0005, respectively) and T_max of chrysophanol and rheochrysidin (P = 0.0101 and 0.0037, respectively) lasted longer in SAP group than in control group.

CONCLUSION: SAP can significantly impact the absorption of DCQD components in rats and their pharmacokinetic parameters.

Effects of Chai-Qin-Cheng-Qi Decoction on cefotaxime in rats with acute necrotizing pancreatitis

AIM: To investigate the effect of Chai-Qin-Cheng-Qi Decoction (CQCQD) on cefotaxime (CTX) concentration in pancreas of rats with acute necrotizing pancreatitis (ANP).

METHODS: Sixty healthy male Sprague-Dawley rats were divided randomly into an ANP group (ANP model + CTX, n = 20), treatment group (ANP model + CTX + CQCQD, n = 20) and control group (normal rats + CTX, n = 20). ANP models were induced by retrograde intraductal injection of 3.5% sodium taurocholate (1 mL/kg), and the control group was injected intraductally with normal saline. All rats were injected introperitoneally with 0.42 g/kg CTX (at 12-h intervals for a continuous 72 h) at 6 h after intraductal injection. Meanwhile, the treatment group received CQCQD (20 mL/kg) intragastrically at 8-h intervals, and the ANP and control group were treated intragastrically with normal saline. At 15 min after the last CTX injection, blood and pancreas samples were collected for the determination of CTX concentration using validated high-performance liquid chromatography. Pathological changes and wet-to-dry-weight (W/D) ratio of pancreatic tissue were examined.

RESULTS: Serum CTX concentrations in three groups were not significantly different. Pancreatic CTX concentration and penetration ratio were lower in ANP group vs control group (4.4 ± 0.6 μg/mL vs 18.6 ± 1.7 μg/mL, P = 0.000; 5% vs 19%, P = 0.000), but significantly higher in treatment group vs ANP group (6.4 ± 1.7 μg/mL vs 4.4 ± 0.6 μg/mL, P = 0.020; 7% vs 5%, P = 0.048). The histological scores and W/D ratio were significantly decreased in treatment group vs ANP and control group.

CONCLUSION: CQCQD might have a promotive effect on CTX concentration in pancreatic tissues of rats with ANP.

Pharmacokinetics of anthraquinones in Xiexin decoction and in different combinations of its constituent herbs

Xiexin decoction (XXD), a classic pyretolysis formula, is composed of Rhei Rhizoma (DH), Radix Scutellaria (HQ) and Coptis Chinensis (HL) and is commonly used in the clinical setting. The aim of this study was to investigate the pharmacokinetic differences of the five anthraquinones in rats after oral administration of XXD and different combinations of its constituent herbs. Twenty rats were randomly divided into four groups and were administered one of the four extracts: DH, DH-HQ, DH-HL and XXD (DH-HQ-HL) via intragastric gavage. Anthraquinone concentrations in plasma were determined by an HPLC technique. Pharmacokinetic parameters were calculated from the plasma concentration-time data. Compared with DH alone, the DH-HL combination decreased C(max) of all five anthraquinones and AUC of four anthraquinones (except physcion), and the DH-HQ combination decreased AUC of aloe-emodin and C(max) of rhein. Finally, XXD increased AUC of all five anthraquinones compared with DH-HL combination. These results showed that the oral bioavailabilities of five anthraquinones were decreased significantly by combining DH with HL, whereas HQ weakened the effect of HL that inhibited the absorption of anthraquinones.

Development and validation of a sensitive LC-MS/MS method with electrospray ionization for quantitation of rhein in human plasma: application to a pharmacokinetic study

A highly sensitive and specific LC-MS/MS method has been developed and validated for the estimation of rhein with 100 microL human plasma using celecoxib as an internal standard (IS). The API-4,000 Q-Trap LC-MS/MS was operated under multiple reaction-monitoring mode using the electrospray ionization technique. The assay procedure involved extraction of rhein and IS from human plasma with acetonitrile, which yielded consistent recoveries of 36.01 and 65.85% for rhein and IS, respectively. The total chromatographic run time was 5.0 min and the elution of rhein and IS occurred at approximately 1.60 and 3.96 min, respectively. The resolution of peaks was achieved with 0.01 m ammonium acetate (pH 6.0):acetonitrile:methanol (30:58:12, v/v) on an Inertsil ODS-3 column. The method was proved to be accurate and precise at a linearity range of 0.005-5.00 microg/mL with a correlation coefficient (r) of >or=0.995. The lower limit of quantitation was 0.005 microg/mL. The intra- and inter-day precision and accuracy values were found to be within the assay variability limits as per the FDA guidelines. Rhein was found to be stable in the battery of stability studies. The application of the assay to pre-clinical pharmacokinetic studies confirmed the utility of the assay to derive pharmacokinetic parameters.