The m6A methyltransferase METTL3 modifies Kcnk6 promoting on inflammation associated carcinogenesis is essential for colon homeostasis and defense system through histone lactylation dependent YTHDF2 binding.

Inflammation induces tumor formation and plays a crucial role in tumor progression and prognosis. KCNK6, by regulating K(+) efflux to reduce NLRP3 Inflammasome-induced lung injury, relaxes the aorta. This study aims to elucidate the effects and biological mechanism of KCNK6 in inflammation-associated carcinogenesis, which may be essential for colon homeostasis and the defense system. To induce colitis, mice were given 3.0% Dextran Sodium Sulfate (DSS) in their drinking water for 7 days. The Azoxymethane (AOM) +DSS method was used to induce colon cancer in the mice model. Bone marrow-derived macrophages (BMDM) from Kcnk6-/- mice, AW264.7 cells, and human colon cancer HCT116 and Caco2 cells were used as in vitro models. The loss of Kcnk6 prevented spontaneous colitis and restored mucosal integrity and homeostatic molecules. Additionally, the loss of Kcnk6 reduced the severity of AOM/DSS-induced carcinogenesis. Kcnk6 promoted cell viability and proliferation in HCT-116 or Caco-2 cells. The loss of Kcnk6 inhibited the levels of inflammatory factors in BMDM cells. Kcnk6 accelerated potassium channel activity, inducing NLRP3 inflammasome activation. METTL3-mediated m6A modification increased Kcnk6 stability in a YTHDF2-dependent manner. Histone lactylation activated the transcription of YTHDF2/Kcnk6. Our study revealed the important role of Kcnk6 in inflammation-associated carcinogenesis progression. The m6A methyltransferase METTL3 and histone lactylation increased Kcnk6 stability in a YTHDF2-dependent manner, providing a potential strategy for inflammation-associated carcinogenesis or colorectal cancer therapy.

Our study revealed the important role of Kcnk6 senescence in inflammation associated carcinogenesis progression. The m6A methyltransferase METTL3 and histone lactylation increased Kcnk6 stability in YTHDF2- dependent manner, providing a potential strategy for inflammation associated carcinogenesis or colorectal cancer therapy.

Chicoric acid advanced PAQR3 ubiquitination to ameliorate ferroptosis in diabetes nephropathy through the relieving of the interaction between PAQR3 and P110α pathway.

PURPOSE: This study aimed to examine the impact of CA on DN and elucidate its underlying molecular mechanisms of inflammation. METHODS: We fed C57BL/6 mice injected with streptozotocin to induce diabetes. In addition, we stimulated NRK-52E cells with 20 mmol/L d-glucose to mimic the diabetic condition. RESULTS: Our findings demonstrated that CA effectively reduced blood glucose levels, and improved DN in mice models. Additionally, CA reduced kidney injury and inflammation in both mice models and in vitro models. CA decreased high glucose-induced ferroptosis of NRK-52E cells by inducing GSH/GPX4 axis. Conversely, the ferroptosis activator or the PI3K inhibitor reversed positive effects of CA on DN in both mice and in vitro models. CA suppressed PAQR3 expression in DN models to promote PI3K/AKT activity. The PAQR3 activator reduced the positive effects of CA on DN in vitro models. Moreover, CA directly targeted the PAQR3 protein to enhance the ubiquitination of the PAQR3 protein. CONCLUSION: Overall, our study has uncovered that CA promotes the ubiquitination of PAQR3, leading to the attenuation of ferroptosis in DN. This effect is achieved through the activation of the PI3K/AKT signaling pathways by disrupting the interaction between PAQR3 and the P110α pathway. These findings highlight the potential of CA as a viable therapeutic option for the prevention of DN and other forms of diabetes.

Apolipoprotein C3 (ApoC3) facilitates NLRP3 mediated pyroptosis of macrophages through mitochondrial damage by accelerating of the interaction between SCIMP and SYK pathway in acute lung injury.

Respiratory failure caused by severe acute lung injury (ALI) is the main cause of mortality in patients with COVID-19.This study aimed to investigate the effects and underlying biological mechanism of Apolipoprotein C3 (ApoC3) in ALI. To establish an in vivo model, C57BL/6 mice were exposed by lipopolysaccharide (LPS). For the in vitro model, murine bone marrow-derived macrophages (BMDMs) or RAW264.7 cells were stimulated with LPS + adenosine triphosphate (ATP). Serum levels of ApoC3 were found to be upregulated in patients with COVID-19 or pneumonia-induced ALI. Inhibition of ApoC3 reduced lung injury in an ALI model, while overexpression of ApoC3 promoted lung injury. ApoC3 induced mitochondrial damage-mediated pyroptosis in ALI through the activation of the NOD-like receptorprotein 3 (NLRP3) inflammasome. ApoC3 recombinant protein significantly increased SCIMP expression in the lung tissue of mice models with ALI. ApoC3 also facilitated the interaction between the SLP adapter and CSK-interacting membrane protein (SCIMP) protein and Spleen tyrosine kinase (SYK) protein in the ALI model. Moreover, ApoC3 accelerated calcium-dependent reactive oxygen species (ROS) production in the ALI model. The effects of ApoC3 on pyroptosis were mitigated by the use of a pyroptosis inhibitor or an ROS inhibitor in the ALI model. Furthermore, ApoC3 activated the expression of SYK, which in turn induced NLRP3 inflammasome-regulated pyroptosis in the ALI model. METTL3 was found to mediate the m6A mRNA expression of ApoC3. Overall, our study highlights the crucial role of ApoC3 in promoting macrophage pyroptosis in ALI through calcium-dependent ROS production and NLRP3 inflammasome activation via the SCIMP-SYK pathway, providing a potential therapeutic strategy for ALI and other inflammatory diseases.

The effects and mechanisms of the anti-COVID-19 traditional Chinese medicine, Dehydroandrographolide from Andrographis paniculata (Burm.f.) Wall, on acute lung injury by the inhibition of NLRP3-mediated pyroptosis.

BACKGROUND: Dehydroandrographolide (Deh) from Andrographis paniculata (Burm.f.) Wall has strong anti-inflammatory and antioxidant activities. PURPOSE: To explore the role of Deh in acute lung injury (ALI) of coronavirus disease 19 (COVID-19) and its inflammatory molecular mechanism. METHODS: Liposaccharide (LPS) was injected into a C57BL/6 mouse model of ALI, and LPS + adenosine triphosphate (ATP) was used to stimulate BMDMs in an in vitro model of ALI. RESULTS: In an in vivo and in vitro model of ALI, Deh considerably reduced inflammation and oxidative stress by inhibiting NLRP3-mediated pyroptosis and attenuated mitochondrial damage to suppress NLRP3-mediated pyroptosis through the suppression of ROS production by inhibiting the Akt/Nrf2 pathway. Deh inhibited the interaction between Akt at T308 and PDPK1 at S549 to promote Akt protein phosphorylation. Deh directly targeted PDPK1 protein and accelerated PDPK1 ubiquitination. 91-GLY, 111-LYS, 126-TYR, 162-ALA, 205-ASP and 223-ASP may be the reason for the interaction between PDPK1 and Deh. CONCLUSION: Deh from Andrographis paniculata (Burm.f.) Wall presented NLRP3-mediated pyroptosis in a model of ALI through ROS-induced mitochondrial damage through inhibition of the Akt/Nrf2 pathway by PDPK1 ubiquitination. Therefore, it can be concluded that Deh may be a potential therapeutic drug for the treatment of ALI in COVID-19 or other respiratory diseases.

Integrating Bioinformatics and Network Pharmacology to Explore the Therapeutic Target and Molecular Mechanisms of Schisandrin on Hypertrophic Cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is the most common inherited heart disease and is currently the leading cause of sudden death in adolescent athletes. Schisandrin is a quality marker of the traditional Chinese medicine Schisandra chinensis, which has an excellent therapeutic effect on HCM, but its pharmacological mechanism remains unclear. OBJECTIVE: This study aimed to explore the potential and provide scientific evidence for schisandrin as a lead compound against hypertrophic cardiomyopathy. METHODS: The drug-like properties of schisandrin were predicted using the SwissADME website. Then, the PharmMapper database was used to predict potential drug targets and match gene names in the Uniprot database. HCM targets were collected from NCBI, OMIM, and Genecards databases and intersected with drug targets. The intersection targets were imported into the STRING database for PPI analysis, and core targets were identified. KEGG and GO enrichment analysis was performed on the core targets through the DAVID database, and all network maps were imported into Cytoscape software for visualization optimization. HCM-related datasets were downloaded from the GEO database to analyze core targets and screen differentially expressed target genes for molecular docking. RESULTS: After the PPI network analysis of the intersection targets of drugs and diseases, 12 core targets were screened out. The KEGG analysis results showed that they were mainly involved in Rap1, TNF, FoxO, PI3K-Akt, and other signaling pathways. After differential analysis, PPARG, EGFR, and MMP3 targets were also screened. The molecular docking results showed that schisandrin was well bound to the protein backbone of each target. CONCLUSION: This study used network pharmacology combined with differential expression and molecular docking to predict that schisandrin may treat HCM by acting on PPARG, EGFR, and MMP3 targets, and the regulatory process may involve signaling pathways, such as Rap1, TNF, FoxO, and PI3K-Akt, which may provide a valuable reference for subsequent studies.

Avenanthramide C from Oats Protects Pyroptosis through Dependent ROS-Induced Mitochondrial Damage by PI3K Ubiquitination and Phosphorylation in Pediatric Pneumonia.

Oat containing rich ß-glucan, polyphenols, flavonoids, saponins, alkaloids, and other substances shows good biological activities. Therefore, the present study aimed to uncover the possible mechanism and therapeutic effect of Avenanthramide C in lessening inflammatory responses in pediatric pneumonia. Pediatric pneumonia was induced by liposaccharide (LPS) for vivo model and vitro model. Macrophage was performed to determine the mechanism and effects of Avenanthramide C in pediatric pneumonia. NLRP3 activity participated in the effects of Avenanthramide C in pediatric pneumonia. Avenanthramide C induced p-PI3K and p-Akt expressions and reduced ubiquitination of PI3K expression in pediatric pneumonia. On the other hand, Avenanthramide C integrated serine at 821 sites of the PI3K protein function. Avenanthramide C reduced ROS (reactive oxygen species)-induced mitochondrial damage by PI3K/AKT function in a model of pediatric pneumonia. Avenanthramide C protects pyroptosis in a model of pediatric pneumonia by PI3K/AKT/Nrf2/ROS signaling. Taken together, our results demonstrated that Avenanthramide C protects pyroptosis through dependent ROS-induced mitochondrial damage by PI3K ubiquitination and phosphorylation in a model of pediatric pneumonia, suggesting its potential use for the treatment of pediatric pneumonia and other inflammatory diseases.

Schisandrin B Attenuates Colitis-Associated Colorectal Cancer through SIRT1 Linked SMURF2 Signaling.

Colon cancer, a common type of malignant tumor, seriously endangers human health. However, due to the relatively slow progress in diagnosis and treatment, the clinical therapeutic technology of colon cancer has not been substantially improved in the past three decades. The present study was designed to investigate the effects and involved mechanisms of schisandrin B in cell growth and metastasis of colon cancer. C57BL/6 mice received AOM and dextran sulfate sodium. Mice in treatment groups were gavaged with 3.75-30 mg/kg/day of schisandrin B. Transwell chamber migration, enzyme-linked immunosorbent assay (ELISA), Western blot analysis, immunoprecipitation (IP) and immunofluorescence were conducted, and HCT116 cell line was employed in this study. Data showed that schisandrin B inhibited tumor number and tumor size in the AOD+DSS-induced colon cancer mouse model. Schisandrin B also inhibited cell proliferation and metastasis of colon cancer cells. We observed that schisandrin B induced SMURF2 protein expression and affected SIRT1 in vitro and in vivo. SMURF2 interacted with SIRT1 protein, and there was a negative correlation between SIRT1 and SMURF2 expressions in human colorectal cancer. The regulation of SMURF2 was involved in the anticancer effects of schisandrin B in both in vitro and in vivo models. In conclusion, the present study revealed that schisandrin B suppressed SIRT1 protein expression, and SIRT1 is negatively correlated with the induction of SMURF2, which inhibited cell growth and metastasis of colon cancer. Schisandrin B could be a leading compound, which will contribute to finding novel potential agents and therapeutic targets for colon cancer.

Using Network Pharmacology for Systematic Understanding of Geniposide in Ameliorating Inflammatory Responses in Colitis Through Suppression of NLRP3 Inflammasome in Macrophage by AMPK/Sirt1 Dependent Signaling.

Ulcerative colitis is a chronic and recurrent inflammatory bowel disease mediated by immune response. Geniposide is the main active ingredient extracted from Gardenia jasminoides, which has been suggested to exert excellent efficacy on inflammatory disease. Herein, in this study, we aimed to uncover the systematic understanding of the mechanism and effects of geniposide in ameliorating inflammatory responses in colitis. In brief, the TCMSP server and GEO DataSets were used to analyze the systematic understanding of the mechanism and effects of geniposide in ameliorating inflammatory responses in colitis. Dextran Sulfate Sodium (DSS)-induced acute colitis of mice were administered with 25-100[Formula: see text]mg/kg of geniposide for 7 days by gavage. Lipopolysaccharide (LPS)-induced Bone Marrow Derived Macrophage (BMDM) cell or RAW264.7 cell models were treated with 20, 50 and 100[Formula: see text][Formula: see text]M of geniposide for 4[Formula: see text]h. Myeloperoxidase (MPO) activity and Interleukin-1[Formula: see text] (IL-1[Formula: see text] levels were measured using MPO activity kits and IL-1[Formula: see text] levels enzyme-linked immunosorbent assay (ELISA) kits, respectively. Additionally, Western blot was used to determine the relevant protein expression. As a result, Geniposide could ameliorate inflammatory responses and prevent colitis in DSS-induced acute colitis of mice by activating AMP-activated protein kinase (AMPK)/Transcription 1 (Sirt1) dependent signaling via the suppression of nod-like receptor protein 3 (NLRP3) inflammasome. Geniposide attenuated macrophage differentiation in DSS-induced acute colitis of mice. Geniposide suppressed NLRP3 inflammasome and induced AMPK/Sirt1 signaling in LPS-induced BMDM cell or RAW264.7 cell models. In mechanism studies, the inhibition of AMPK/Sirt1 attenuated the anti-inflammatory effects of geniposide in colitis. The activation of NLRP3 attenuated the anti-inflammatory effects of geniposide in colitis. Taken together, our results demonstrated that geniposide ameliorated inflammatory responses in colitis vai the suppression of NLRP3 inflammasome in macrophages by AMPK/Sirt1-dependent signaling.

Circular RNA circCUL3 Accelerates the Warburg Effect Progression of Gastric Cancer through Regulating the STAT3/HK2 Axis.

The Warburg effect is a significant hallmark of gastric cancer (GC), and increasing evidence emphasizes the crucial role of circular RNAs (circRNAs) in GC tumorigenesis. However, the precise molecular mechanisms by which circRNAs drive the GC Warburg effect are still elusive. The present study was designed to unveil the roles of circRNAs and the corresponding potential mechanism. High-regulated expression of circCUL3 was observed in both GC tissues and cell lines. Clinically, the high expression of circCUL3 was closely correlated with advanced clinical stage and overall survival in GC patients. Functionally, cellular experimental investigations demonstrated that circCUL3 promoted the proliferation, glucose consumption, lactate production, ATP quantity, and extracellular acidification rate (ECAR) of GC cells. In vivo, circCUL3 knockdown repressed tumor growth. Mechanistic analysis demonstrated that circCUL3 promoted signal transducer and activator of transcription (STAT)3 expression through sponging miR-515-5p; moreover, transcription factor STAT3 accelerated the transcriptional level of hexokinase 2 (HK2). In summary, the present findings provide mechanistic insights into circCUL3/miR-515-5p/STAT3/HK2 axis regulation on the GC Warburg effect, providing a novel possibility for an understanding of GC pathogenesis.

Tubeimoside­1 induces apoptosis in human glioma U251 cells by suppressing PI3K/Akt­mediated signaling pathways.

Tubeimoside-1 (TBMS1), a traditional Chinese herb extracted from Bolbostemma paniculatum (Maxim.), induces apoptosis in a number of human cancer cell lines. TBMS1 has been reported to induce apoptosis in human glioma cells, however the mechanism remains to be elucidated. The present study explored TBMS1­induced PI3K/Akt­related pathways in human glioma cells. The human glioma U251 and the human astrocyte (HA) cell lines were treated with various concentrations of TBMS1. MTT assays were conducted to analyze cell viability. Cell cycle distribution and the rate of apoptosis were assessed using flow cytometry. BrdU incorporation and Hoechst 33342 staining were performed to analyze the cell cycle and apoptosis, respectively. Western blotting was performed to investigate protein expression levels. The results demonstrated that TBMS1 reduced cell viability in human glioma cells U251 by suppressing Akt phosphorylation. Subsequently, TBMS1 inhibited DNA synthesis and induced G2/M phase arrest by targeting the PI3K/Akt/p21 and the cyclin­dependent kinase 1/cyclin B1 signaling cascades. In addition, TBMS1 triggered apoptosis via the PI3K/Akt­mediated Bcl­2 signaling pathway. These results demonstrated that TBMS1 prevented the progression of gliomas via the PI3K/Akt­dependent pathway, which provided a theoretical basis for in vivo studies to use TBMS1 as potential therapy for the prevention of cancer.

Dual roles of IL-18 in colitis through regulation of the function and quantity of goblet cells.

The main aim of the present study was to investigate the dual roles and mechanism of interleukin (IL)­18 in dextran sulfate sodium (DSS)­induced colitis. Firstly, meta­analysis was used to explore whether the levels of IL­18 were different in patients with colon cancer or inflammatory bowel disease. The results demonstrated that IL­18 (rs187238, ­137G/C) increased the incidence rate of colon cancer in patients, while IL­18 (rs187238, ­137G/C) decreased the incidence rate of ulcerative colitis or Crohn's disease in patients. Therefore, IL­18 (rs187238, ­137G/C) may have a dual function in colitis. Next, the functional role of IL­18 in colitis was further investigated, by use of a DSS­induced colitis mouse model. Pre­treatment of the mice with IL­18 increased body weight, augmented colon length, reduced inflammatory infiltration, promoted mucin (Muc)­2 expression, increased the function and quantity of goblet cells and increased the mRNA levels of resistin­like molecule (RELM) ß and trefoil factor family (TFF) 3 in mice with DSS­induced colitis, through the IL­22/STAT3 pathway. By contrast, treatment with IL­18 at later stages of the disease reduced body weight, decreased colon length, enhanced inflammatory infiltration and reduced Muc­2 expression, decreased the function and quantity of goblet cells and inhibited the mRNA levels of RELMß and TFF3 in mice with DSS­induced colitis. In conclusion, IL­18 served a dual function in colitis by regulating the function of goblet cells. The anti­inflammatory effects of IL­18 were observed in the early stage of colitis­induced inflammation, while the pro­inflammatory effects were observed in the later stages of the disease.

Effect of OATP1B1 genetic polymorphism on the uptake of tamoxifen and its metabolite, endoxifen.

Overexpression lentivirus platform was established of OATP1B1 (organic anion transporting polypeptides 1B1) wild­type and mutant type genetic polymorphism in vitro, and using this platform we investigated and compared the uptake of tamoxifen and its metabolites by mutating the 388 and the 521 bases. The overexpression lentivirus cell platforms were successfully constructed, including OATP1B1*1a-HEK293T and OATP1B1*1b-HEK293T and OATP1B1*5-HEK293T cell model, the infection efficiency is not less than 80%. It shows a high level of gene expression at the mRNA and protein level. The tamoxifen and endoxifen can be taken up into the cells through organic anion transporter polypeptide 1B1, and OATP1B1521T>C inhibits the function of the transport protein, resulting in the content of drug in cell lysis liquid in OATP1B1*5-HEK293T group is lower than in OATP1B1*1a-HEK293T group (tamoxifen or endoxifen), with statistical significance. The content of the drug in cell lysis liquid in OATP1B1*1b-HEK293T group and the OATP1B1*1a-HEK293T group, similar with no statistical significance. These results suggest that tamoxifen and endoxifen can be transported by OATP1B1. However, OATP1B1 521T>C can inhibit the effects of OATP1B1 on tamoxifen and endoxifen in the cells.

Clinicalpathological and prognostic significance of survivin expression in renal cell carcinoma: a meta-analysis.

BACKGROUND: In recent years, survivin expression had been investigated as a prognostic biomarker for renal cell carcinoma (RCC), however, the results were conflicting. This study was aimed to explore the association between survivin expression and clinicalpathological features and the prognostic value for cancer-specific survival (CSS) and overall survival (OS) in RCC. RESULTS: Eleven studies with 1,697 subjects were included in this meta-analysis. The results showed that survivin expression was associated with higher tumor grade (OR=4.25, 95%CI: 3.04-5.95, p<0.001), advanced tumor stage (OR=3.83, 95%CI: 2.01-7.3, p<0.001) and lymph node metastasis (OR=4.19, 95%CI: 2.34-7.52, p<0.001), but had no association with age, gender or distant metastasis. In addition, survivin expression was also correlated with poor CSS (HR=2.08, 95%CI: 1.07-4.05, p=0.032) and poor OS (HR=2.28, 95%CI: 1.57-3.33, p<0.001). MATERIALS AND METHODS: Literature was searched by PubMed, Embase and Web of Science. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were extracted from eligible studies. Fixed or random effects model were used to calculate pooled HRs and 95%CIs according to heterogeneity. CONCLUSIONS: This study demonstrated that survivin expression was associated with more aggressive clinical features and predicted poor CSS and OS in patients with RCC.

Establishment of an expression platform of OATP1B1 388GG and 521CC genetic polymorphism and the therapeutic effect of tamoxifen in MCF-7 cells.

The present study was designed to evaluate the gene polymorphisms of organic anion transporting polypeptide 1B1 (OATP1B1) in predicting the therapeutic efficacy of tamoxifen (TAM) for MCF-7. Established plasmids OATP1Bl wild-type 388GG and 521CC were transfected into MCF-7 cells and used to determine whether the gene polymorphisms affected the therapeutic efficacy of TAM for MCF-7. The established plasmids pcDNA3.1(-)-OATP1B1 wild-type 388GG and 521CC were digested by restriction enzymes and analyzed by gene sequencing. The gene polymorphisms of OATP1Bl in MCF-7 breast cancer cells were examined by RT-PCR and western blot analysis. The results showed that the mutations of OATP1B1 388GG and 521CC led to a decrease of the inhibition and apoptotic rates of MCF-7 cells, albeit not significantly compared to the OATP1B1 group. The G0/G1 phase length ratio was reduced, and the S and G2M phases were increased in the OATP1B1 388GG and 521CC groups, although not significantly compared to the OATP1B1 group. The mutations of OATP1B1 388GG and 521CC inhibited the activity of OATP1B1 protein, restrained the turnover capacity of OATP1B1 and reduced the entrance of TAM into MCF-7 cells, resulting in weakened efficacy of TAM in the treatment of breast cancer.

Association of CYP2D6*10, OATP1B1 A388G, and OATP1B1 T521C polymorphisms and overall survival of breast cancer patients after tamoxifen therapy.

BACKGROUND: The global incidence of breast cancer is increasing, mainly due to the sharp rise in breast cancer incidence in Asia. The aim of this study was to evaluate the association of CYP2D6*10 (c.100C>T and c.1039C>T), OATP1B1 A388G, and OATP1B1 T521C polymorphisms with overall survival (OS) for hormone receptor (estrogen receptor or progesterone receptor)-positive tumors (ER+/PR+) breast cancer patients after adjuvant tamoxifen (TAM) therapy. MATERIAL AND METHODS: We included 296 invasive breast cancer patients with hormone receptor-positive tumors during the period 2002-2009. We collected patient data, including clinical features, TAM therapy, and survival status. Archived paraffin blocks from surgery were the source of tissue for genotyping. CYP2D6*10, OATP1B1 A388G, and T521C polymorphisms were detected by direct sequencing of genomic DNA. OS was assessed with Kaplan-Meier analysis, while the Cox proportional hazards model was used to implement multivariate tests for the prognostic significance. RESULTS: There was a significant difference in OS between OATP1B1 T521C wild-type and the mutant genotype C carrier (P=0.034). However, there was no difference in overall survival between wild-type and carrier groups for CYP2D6*10 (P=0.096) and OATP1B1 A388G (P=0.388), respectively. CONCLUSIONS: These results suggest that the OATP1B1 T521C mutation may be an independent prognostic marker for breast cancer patients using TAM therapy.

Sensitive determination of 20(S)-protopanaxadiol in rat plasma using HPLC-APCI-MS: application of pharmacokinetic study in rats.

20(S)-Protopanaxadiol (PPD), the main metabolite of protopanoxadiol type ginsenosides (e.g. Rg3 and Rh2), is a very promising anti-cancer drug candidate. To evaluate the pharmacokinetic property of PPD, we reported a reliable, sensitive and simple method utilizing liquid chromatography (HPLC)-atmospheric pressure chemical ionization-mass spectrometry (APCI-MS) to determine PPD. PPD and the internal standard, panoxadiol (PD) were extracted from plasma with acetic ether, separated on a C18 reverse column, and then analyzed by APCI-MS. Targeting fragment ion at m/z 425 for both PPD and PD was monitored in selected-ion monitoring (SIM) mode. PPD can be quantitatively determined at the concentration as low as 1 ng/mL using 200 microL plasma. And the sensitive method showed excellent linearity over a range from 1 to 1000 ng/mL, high recovery, accuracy and precision at the concentrations of 2.5, 100.0 and 1000.0 ng/mL, respectively. The method was successfully applied to pharmacokinetic study of PPD in rats. Pharmacokinetic parameters were calculated and absolute bioavailability of PPD was 36.8+/-12.4%, at least ten times higher than that of Rg3 and Rh2, indicating its good absorption in gastrointestinal tract. It was further suggested that PPD be a promising anti-cancer candidate and probably responsible for the observed pharmacological activity of Rg3 and Rh2.

Pharmacokinetics of rosuvastatin when coadministered with rifampicin in healthy males: a randomized, single-blind, placebo-controlled, crossover study.

BACKGROUND: Rifampicin (rifampin) has been reported to have drug-drug interaction with several 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors due to its ability to influence the function of cytochrome P450 enzymes or transporters. Rosuvastatin is absorbed from the blood into the liver by organic anion transporting polypeptide 1B1 and is then metabolized by cytochrome P450 isozyme 2C9. OBJECTIVE: The aim of this study was to examine the effect of rifampicin on the pharmacokinetics of rosuvastatin. METHODS: This was a randomized, single-blind, placebo-controlled, crossover study, with a 4-week washout period. Healthy male volunteers were treated for 6 days with rifampicin 450 mg or placebo once daily. On days 0 and 7, a single oral dose of rosuvastatin 20 mg was administered. Plasma concentrations of rosuvastatin were measured by liquid chromatography-tandem mass spectrometry. RESULTS: A total of 18 healthy Chinese male volunteers (mean [SD] age, 21 [2] years; weight, 62 [7] kg; and body mass index was within the normal range [22.0-24.0 kg/m2]) were included in the study. The plasma concentrations of rosuvastatin were not significantly changed by pretreatment with rifampicin, although there was considerable interindividual variation in the plasma concentration of rosuvastatin. During the rifampicin phase, the AUC(0-infinity) of rosuvastatin decreased in 10 and increased in 8 of the 18 subjects. In 3 of the 8 subjects, the AUC(0-infinity) of rosuvastatin during the rifampicin phase was > or = 50% compared with the placebo phase; and only 1 increased by more than double (183%). Of those in the decreased group (n = 10), the AUC(0-infinity) values were decreased by >50% in 3 subjects and were not decreased by >30% in the remaining 7 subjects. The mean AUC(0-infinity) of rosuvastatin was 95.8% (110.4 [41.4] vs 115.3 [30.9] ng/mL . h(-1)) of the corresponding value during the placebo phase (P = NS). There was no statistically significant difference in either C(max) or t(1/2) of rosuvastatin between the rifampicin-treated and placebo groups (18.5 [6.3] vs 16.5 [5.5] ng/mL; 12.8 [3.0] vs 13.3 [2.8] h). The oral clearance of rosuvastatin was not significantly affected by rifampicin pretreatment either (0.4 [0.3] vs 0.3 [0.2] L . h; P = 0.072). CONCLUSION: The pharmacokinetics of rosuvastatin were not significantly changed by coadministration of rifampicin in this small group of healthy male volunteers.

Pharmacokinetics, tissue distribution and excretion of a new photodynamic drug deuxemether.

Deuxemether was a new photodynamic drug effective for many kinds of solid tumor therapy, which was mainly composed of 3-(or 8-)-(1-methoxyethyl)-8-(or 3-)-(1-hydroxyethyl)-deutero-porphyrin IX (MHD) and 3,8-di(1-methoxyethyl)-deuteroporphyrin IX (DMD). The aims of this study were to elucidate its pharmacokinetic characteristics, tissue distribution, plasma protein binding and excretion properties and underlying mechanisms of deuxemether in rats based on the simultaneous determination of MHD and DMD. The pharmacokinetic profiles of both MHD and DMD in rats after intravenous doses were linear and best fitted to a two compartment model, characterized with a rapid distribution phase (MHD: t(1/2)alpha, 0.09-0.14 h; DMD: t 1/2 alpha, 0.07-0.11h) and a relatively slow elimination phase (MHD: t 1/2 beta, 2.03-3.20 h; DMD: t 1/2 beta, 2.51-3.20 h). The tissue distributions of MHD and DMD in rats were rather limited as evidenced from their low distribution volume (0.75-1.70 L/kg) and the results of tissue distribution study. Protein binding of MHD and DMD were moderate (65.36-89.99% for MHD; 45.43-76.23% for DMD), independent of drug concentrations and similar between human and rat plasma over a concentration range of 0.50-50.0 microg/mL. Both MHD and DMD were predominantly (>74.1%) eliminated from rats as the parent drugs through the hepatobiliary systems and finally excreted into the feces. The multidrug resistance-associated proteins 2 (MRP2) inhibitors, bromosulfophthalein and probenecid, substantially inhibited the hepatobiliary elimination of MHD and DMD while the P-gp inhibitor digoxin had little effect, suggesting that MRP2 may contribute to the rapid and extensive hepatobiliary excretion of deuxemether. There were no significant differences between MHD and DMD for all pharmacokinetic characteristics studied. In conclusion, this study provided firstly the full pharmacokinetic characteristics and mechanisms of deuxemether, which would be helpful for its clinical regiment design.

Quantitative determination of ginsenoside Rh2 in rat biosamples by liquid chromatography electrospray ionization mass spectrometry.

Ginsenoside Rh2 is a "hot" natural compound with great potential as a new anti-cancer drug based on abundant pharmacological experiments. However, no systemic pharmacokinetic study of Rh2 was reported because current analysis methods could not fully meet the requirements. Thus, we developed a simple LC/MS method with highly improved sensitivities for the determination of Rh2 in rat plasma, bile, urine, feces and most tissues. The tissues and feces were firstly homogenized mechanically using buffer and methanol as the media, respectively. Plasma, bile, urine and tissue homogenates were extracted with diethyl ether for sample preparation. Feces homogenates were directly deproteinized with acetonitrile. The subsequent analysis procedures were performed on a Shimadzu LCMS2010A system (electrospray ionization single quadrupole mass analyzer), with an ODS column (150 mm x 2.0-mm i.d., 5 microm) plus a C18 guard column for separation and ammonium chloride (500 micromol) as mobile phase additive. The proportions of mobile phase were changed timely according to gradient programs. Chlorinated adducts of molecular ions [M + Cl]- of Rh2 at m/z 657.35 and internal standard digitoxin at m/z 799.55 were monitored in selective ion monitoring mode of negative ions. The method was validated to be accurate, precise and rugged with good linearity in all matrices, according to the FDA guidelines. The lower limits of quantitation in rat plasma, urine and feces were 0.2, 0.2 and 20 ng/mL respectively. Stability studies were also performed, indicating that there were no stability-related problems in the analytical procedure of Rh2. The proposed method was successfully applied to the preclinical pharmacokinetic research of Rh2 in rats, including plasma kinetics, tissue distribution and excretion studies.

Development of a HPLC-MS assay for ginsenoside Rh2, a new anti-tumor substance from natural product and its pharacokinetic study in dogs.

To develop a HPLC-MS method of determining ginsenoside Rh2 in dog plasma based on solid-phase extraction for pharmacokinetic studies. Six dogs were randomly assigned to two groups, either given 0.1 mg/kg dose intravenously or 1 mg/kg dose through oral gavage. Analysis using high performance liquid chromatography (HPLC) with ODS column, followed by detection with electrospray ionization(ESI) mass spectrometry(MS) in negative ion mode with 500 microM ammonium chloride in the mobile phase. The assays were validated over the concentration range of 2.0-1250.0 ng/ml in dog plasma. The intra- and inter- day precision were less than 10% in terms of RSD. The overall recovery was more than 80%. The validated assay was suitable for pharmacokinetic studies of ginsenoside Rh2 and the observed oral bioavailabilities of Rh2 were 17.6% and 24.8% for male and female dogs respectively.