Systems Theory-Driven Framework for AI Integration into the Holistic Material Basis Research of Traditional Chinese Medicine

This paper introduces a systems theory-driven framework to integration artificial intelligence(AI)into traditional Chinese medicine(TCM)research,enhancing the understanding of TCM’s holistic material basis while adhering to evidence-based principles.Utilizing the System Function Decoding Model(SFDM),the research progresses through define,quantify,infer,and validate phases to systematically explore TCM’s material basis.It employs a dual analytical approach that combines top-down,systems theory-guided perspectives with bottom-up,elements-structure-function methodologies,provides comprehensive insights into TCM’s holistic material basis.Moreover,the research examines AI’s role in quantitative assessment and predictive analysis of TCM’s material components,proposing two specific AIdriven technical applications.This interdisciplinary effort underscores AI’s potential to enhance our understanding of TCM’s holistic material basis and establishes a foundation for future research at the intersection of traditional wisdom and modern technology.

Tanshinone IIA ameliorates energy metabolism dysfunction of pulmonary fibrosis using 13C metabolic flux analysis

Evidence indicates that metabolic reprogramming characterized by the changes in cellular metabolic patterns contributes to the pathogenesis of pulmonary fibrosis (PF). It is considered as a promising therapeutic target anti-PF. The well-documented against PF properties of Tanshinone IIA (Tan IIA) have been primarily attributed to its antioxidant and anti-inflammatory potency. Emerging evidence suggests that Tan IIA may target energy metabolism pathways, including glycolysis and tricarboxylic acid (TCA) cycle. However, the detailed and advanced mechanisms underlying the anti-PF activities remain obscure. In this study, we applied [U-13C]-glucose metabolic flux analysis (MFA) to examine metabolism flux disruption and modulation nodes of Tan IIA in PF. We identified that Tan IIA inhibited the glycolysis and TCA flux, thereby suppressing the production of transforming growth factor-β1 (TGF-β1)-dependent extracellular matrix and the differentiation and proliferation of myofibroblasts in vitro. We further revealed that Tan IIA inhibited the expression of key metabolic enzyme hexokinase 2 (HK2) by inhibiting phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR)/hypoxia-inducible factor 1α (HIF-1α) pathway activities, which decreased the accumulation of abnormal metabolites. Notably, we demonstrated that Tan IIA inhibited ATP citrate lyase (ACLY) activity, which reduced the collagen synthesis pathway caused by cytosol citrate consumption. Further, these results were validated in a mouse model of bleomycin-induced PF. This study was novel in exploring the mechanism of the occurrence and development of Tan IIA in treating PF using 13C-MFA technology. It provided a novel understanding of the mechanism of Tan IIA against PF from the perspective of metabolic reprogramming.

Mogroside IIE,an in vivo metabolite of sweet agent,alleviates acute lung injury via Pla2g2a-EGFR inhibition

In the face of increasingly serious environmental pollution,the health of human lung tissues is also facing serious threats.Mogroside IIE(M2E)is the main metabolite of sweetening agents mogrosides from the anti-tussive Chinese herbal Siraitia grosvenori.The study elucidated the anti-inflammatory action and molecular mechanism of M2E against acute lung injury(ALI).A lipopolysaccharide(LPS)-induced ALI model was established in mice and MH-S cells were employed to explore the protective mechanism of M2E through the western blotting,co-immunoprecipitation,and quantitative real time-PCR analysis.The results indicated that M2E alleviated LPS-induced lung injury through restraining the activation of secreted phospholipase A2 type IIA(Pla2g2a)-epidermal growth factor receptor(EGFR).The interaction of Pla2g2a and EGFR was identified by co-immunoprecipitation.In addition,M2E protected ALI induced with LPS against inflammatory and damage which were significantly dependent upon the downregulation of AKT and m TOR via the inhibition of Pla2g2a-EGFR.Pla2g2a may represent a potential target for M2E in the improvement of LPS-induced lung injury,which may represent a promising strategy to treat ALI.

Populational change of CD4^(+)CD25^(+)Treg cells is responsible for the synergistic effect of the combination of RAMP2 with baicalin in treating recurrent spontaneous abortion mouse models

Background: The absence of a safe and effective therapy for recurrent spontaneous abortion due to a maternofetal failure in immunological tolerance remains an intractable clinical obstacle for surgeons. Recently, traditional Chinese medicine has become a feasible alternative for certain diseases, including recurrent spontaneous abortion. However, because of the complex composition of the traditional Chinese medicine formula, its action mechanism remains unclear. Methods: We selected two isolated active ingredients (RAMP and baicalin) from the traditional Chinese medicine formula and used an abortion-prone CBA/J × DBA/2 model to simulate human RSA and compared the changes in fetal resorption rate, Treg cell percentage, and relevant cytokines before and after combination therapy. In addition, The mechanisms were preliminarily discussed using in vitro differentiation models. Results: In CBA/J × DBA/2 abortion-prone mice, the combination therapy resulted in a lower embryo resorption rate compared to that obtained with individual delivery of either RAMP or baicalin, thereby playing an embryo-protective role through the increase in Treg cells for the maintenance of maternal-fetal immune tolerance. In in vitro primary cell differentiation experiments, the concentration of Treg cells significantly increased from 11% to 17.9% after the combination therapy compared to that of the single administration group. Conclusion: the synergistic effects of RAMP and baicalin were responsible for Treg differentiation. The present study provides a solid basis for improving the applicability of traditional Chinese herbs in the treatment of recurrent spontaneous abortion.

Progress in pathogenesis and treatment of type A hepatic encephalopathy in acute liver failure:a comprehensive review

Hepatic encephalopathy is a serious neuropsychiatric complication caused by liver failure,which is characterized by the development of cognitive and motor disorders into coma.Typically,hepatic encephalopathy can be divided into three types(A,B,and C)according to the etiology.Type A hepatic encephalopathy(AHE)caused by acute liver failure seriously affects the prognosis of patients,ranging from mild neuropsychological changes to coma,brain edema,and even death.So far,the research on the pathogenesis of AHE has focused on the toxic effects of ammonia on the central nervous system,metabolic disorders(glutamine and lactate accumulation),neurotransmission alteration,systemic inflammation,especially neuro-inflammation.All these mechanisms are not independent,but mutually have synergistic effects.In clinic,treatment of AHE based on only one mechanism is often ineffective.To clarify the pathogenesis and the interaction among the mechanisms will be beneficial to the effective treatment of AHE and reduce the mortality.The aim of this review is to provide comprehensive scientific evidence for the clinical treatment of AHE via collecting and analyzing the latest mechanism of AHE,and clarifying the relationship among these mechanisms combing the investigation of the latest research progress of drug treatment of acute liver failure.Consequently,we find that the pathogenesis of AHE is a complex neurocognitive disorder shaped by interactions among hyperammonemia,inflammation,and changes in neurotransmission,the signaling pathways thereby integrating the inflammatory and neurological inputs to impact pathophysiological or neurobehavioral outcomes.

Recent advances in research on natural product inhibitors of SREBPs

Sterol regulatory element-binding proteins(SREBPs)are a class of cholesterol-sensitive transcription factors that play important roles in lipid metabolism.Natural product inhibitors of SREBPs have been shown to inhibit the synthesis of free fatty acids and cholesterol,promote the burning of brown fat,and relieve insulin resistance by inhibiting different links during the synthesis,cleavage,and transport of SREBPs,thereby improving obesity,diabetes,atherosclerosis,and other metabolic diseases and disorders.There are numerous Chinese herbal medicines with verified efficacy in the treatment of metabolic diseases,including Coptis chinensis Franch.and Pueraria peduncularis Grah.for diabetes,Pueraria peduncularis Grah.,Epimedium brevicornum Maxim.,and Panax ginseng C.A.Meyer for osteoporosis,and Nelumbo nucifera Gaertn.and Poria cocos(Schw.)Wolf.for obesity.Present-day research on the mechanisms underlying the activity of traditional Chinese medicine has indicated that certain chemical components of these traditional preparations can be used to treat metabolic diseases by inhibiting SREBPs.Progress in the research on natural product SREBP inhibitors is continuing apace,and the mechanisms of action of certain small molecules have become well established.In this study,we review recent progress in the research on natural small-molecule inhibitors of SREBPs,including flavonoids,saponins,triterpenoids,and alkaloids,which we hope will provide a useful reference for future research and development of drugs for the treatment of metabolic diseases.

The parallel biosynthesis routes of hyperoside from naringenin in Hypericum monogynum

Hyperoside is a bioactive flavonoid galactoside in both medicinal and edible plants.It plays an important physiological role in the growth of flower buds.However,the hyperoside biosynthesis pathway has not been systematically elucidated in plants,including its original source,Hypericaceae.Our group found abundant hyperoside in the flower buds of Hypericum monogynum,and we sequenced its transcriptome to study the biosynthetic mechanism of hyperoside.After gene screening and functional verification,four kinds of key enzymes were identified.Specifically,HmF3Hs(flavanone 3-hydroxylases)and HmFLSs(flavonol synthases)could catalyze flavanones into dihydroflavonols,as well as catalyzing dihydroflavonols into flavonols.HmFLSs could also convert flavanones into flavonols and flavones with varying efficiencies.HmF3′H(flavonoid 3′-hydroxylase)was found to act broadly on 4′-hydroxyl flavonoids to produce 3′,4′-diydroxylated flavanones,dihydroflavonols,flavonols,and flavones.HmGAT(flavonoid 3-O-galactosyltransferase)would transform flavonols into the corresponding 3-O-galactosides,including hyperoside.The parallel hyperoside biosynthesis routes were thus depicted,one of which was successfully reconstructed in Escherichia coli BL21(DE3)by feeding naringenin,resulting in a hyperoside yield of 25 mg/l.Overall,this research not only helped us understand the interior catalytic mechanism of hyperoside in H.monogynum concerning flower development and bioactivity,but also provided valuable insights into these enzyme families.

Nonclinical Study of the Active Components of Doxorubicin Hydrochloride Liposome Injection in Vivo

Objectives: A non-clinical study was performed to establish a LC-MS/MS method to determine the in vivo active components of doxorubicin hydrochloride liposome injection in the plasma of Sprague-Dawley rats. Methods: Ten male SD rats were administered tail vein with a single dose of 10 mg/kg, and the concentrations of doxorubicin hydrochloride in plasma, heart, liver, spleen, lung, and kidney were determined by liquid chromatography-tandem mass spectrometry, and the pharmacokinetic parameters were calculated. Results: The final concentration of doxorubicin hydrochloride ranged from 500 ng/mL to 250,000 ng/mL, and the lower limit of quantification was 500 ng/mL;the main pharmacokinetic parameters: T1/2 was (19.282 ± 10.305) h, Cmax was (118514.828 ± 26155.134) ng/mL, AUC0-24 and AUC0-∞ were (1216659.205 ± 192706.268) ng/mL⋅h and (2082244.523 ± 860139.487) ng/mL⋅h, MRT0-24 and MRT0-∞ were (9.237 ± 0.423) h and (26.52 ± 14.015) h, respectively, and clearance (CL) was (0.005 ± 0.002) mL/h⋅ng. Conclusions: The method is simple, rapid, and sensitive, which can be used for the determination of doxorubicin hydrochloride concentration in the plasma of SD rats and pharmacokinetic non-clinical studies.

A naturally derived small molecule compound suppresses tumor growth and metastasis in mice by relieving p53-dependent repression of CDK2/Rb signaling and the Snail-driven EMT

The tumor suppressor protein p53 is central to cancer biology,with its pathway reactivation emerging as a promising therapeutic strategy in oncology.This study introduced LZ22,a novel compound that selectively inhibits the growth,migration,and metastasis of tumor cells expressing wild-type p53,demonstrating ineffectiveness in cells devoid of p53 or those expressing mutant p53.LZ22’s mechanism of action involves a high-affinity interaction with the histidine-96 pocket of the MDM2 protein.This interaction disrupted the MDM2-p53 binding,consequently stabilizing p53 by shielding it from proteasomal degradation.LZ22 impeded cell cycle progression and diminished cell proliferation by reinstating the p53-dependent suppression of the CDK2/Rb signaling pathway.Moreover,LZ22 alleviated the p53-dependent repression of Snail transcription factor expression and its consequent EMT,effectively reducing tumor cell migration and distal metastasis.Importantly,LZ22 administration in tumor-bearing mice did not manifest notable side effects.The findings position LZ22 as a structurally unique reactivator of p53,offering therapeutic promise for the management of human cancers with wild-type TP53.

Saikosaponin D improves nonalcoholic fatty liver disease via gut microbiota-bile acid metabolism pathway

Non-alcoholic fatty liver disease(NAFLD)is the main cause of chronic liver disease worldwide.Bupleurum is widely used in the treatment of non-alcoholic fatty liver,and saikosaponin D(SSD)is one of the main active components of Bupleurum.The purpose of this study was to investigate the efficacy of SSD in the treatment of NAFLD and to explore the mechanism of SSD in the improvement of NAFLD based on“gut-liver axis”.Our results showed that SSD dose-dependently alleviated high fat diet-induced weight gain in mice,improved insulin sensitivity,and also reduced liver lipid accumulation and injury-related biomarkers aspartate aminotransferase(AST)and alanine aminotransferase(ALT).Further exploration found that SSD inhibited the mRNA expression levels of farnesoid X receptor(Fxr),small heterodimer partner(Shp),recombinant fibroblast growth factor 15(Fgf15)and apical sodium dependent bile acid transporter(Asbt)in the intestine,suggesting that SSD improved liver lipid metabolism by inhibiting intestinal FXR signaling.SSD can significantly reduce the gut microbiota associated with bile salt hydrolase(BSH)expression,such as Clostridium.Decreased BSH expression reduced the ratio of unconjugated to conjugated bile acids,thereby inhibiting the intestinal FXR.These data demonstrated that SSD ameliorated NAFLD potentially through the gut microbiota-bile acidintestinal FXR pathway and suggested that SSD is a promising therapeutic agent for the treatment of NAFLD.

Functional annotation map of natural compounds in traditional Chinese medicines library: TCMs with myocardial protection as a case

The chemical complexity of traditional Chinese medicines(TCMs) makes the active and functional annotation of natural compounds challenging. Herein, we developed the TCMs-Compounds Functional Annotation platform(TCMs-CFA) for large-scale predicting active compounds with potential mechanisms from TCM complex system, without isolating and activity testing every single compound one by one. The platform was established based on the integration of TCMs knowledge base, chemome profiling, and high-content imaging. It mainly included:(1) selection of herbal drugs of target based on TCMs knowledge base;(2) chemome profiling of TCMs extract library by LC-MS;(3) cytological profiling of TCMs extract library by high-content cell-based imaging;(4) active compounds discovery by combining each mass signal and multi-parametric cell phenotypes;(5) construction of functional annotation map for predicting the potential mechanisms of lead compounds. In this stud TCMs with myocardial protection were applied as a case study, and validated for the feasibility and utility of the platform. Seven frequently used herbal drugs(Ginseng, etc.) were screened from 100,000 TCMs formulas for myocardial protection and subsequently prepared as a library of 700 extracts. By using TCMs-CFA platform, 81 lead compounds, including 10 novel bioactive ones, were quickly identified by correlating 8089mass signals with 170,100 cytological parameters from an extract library. The TCMs-CFA platform described a new evidence-led tool for the rapid discovery process by data mining strategies, which is valuable for novel lead compounds from TCMs. All computations are done through Python and are publicly available on GitHub.

Total glucosides of paeony attenuates animal psoriasis induced inflammatory response through inhibiting STAT1 and STAT3 phosphorylation

OBJECTIVE Psoriasis is an immune system meditated disease,especially T cells.It disturbed many people around the world and hard to therapy.Paeonia lactiflora Pall has been used as a medicine in china for thousands of years.Recent studies has found that the main component of Paeonia lactiflora Pall can alleviates the immune response in many diseases.In this study,we researched the effects and possible mechanisms of total glucosides of paeony(TGP)on animal psoriasis in order to study the therapeutic effects and mechanisms of TGP in 5%propranolol creaminduced psoriasis in guinea pigs and Imiquimod(IMQ)cream-induced psoriasis in mice.METHODS The effect of TGP was evaluated using a psoriasis-like model of guinea pigs and mice.Ear thickness was accessed,and pathology injury was observed by HE staining.The levels of serum IL-1β,IL-6,IL-12,IL-17,IL-23,TNF-α,and IFN-γ,skin IL-17A,IL-22 and orphan nuclear receptor(RORγt)mRNA expression,proliferating cell nuclear antigen(PCNA),total or phosphorylated signal transducers and activators of transcription(STAT1 and STAT3)were determined by ELISA,real time PCR,immu⁃nohistochemical staining,and Western blotting,respectively.RESULTS Compared with model group,TGP treatment decreased the ear thickness,improved pathology of psoriasis,alleviated IMQ-induced keratinocyte proliferation,reduced the inflammatory cytokine,and downregulated IL-17A,IL-22,and RORγt mRNA in mice.Further study indicated that TGP inhibited STAT1 and STAT3 phosphorylation in lesion skins of psoriasis-like mice.CONCLUSION TGP alleviates the symptoms of psoriasis-like guinea pigs and mice,and the possible mechanism may relate to inhibit T helper 17(TH17)cell differentiation and keratinocytes proliferation by inhibiting STAT1 and STAT3 phosphorylation.

Hepatoprotective effects of baicalein against CCl 4-induced acute liver injury in mice

AIM:To investigate the hepatoprotective effect of baicalein against carbon tetrachloride(CCl 4)-induced liver damage in mice.METHODS:Mice were orally administered with baicalein after CCl 4 injection,and therapeutic baicalein was given twice a day for 4 d.The anti-inflammation effects of baicalein were assessed directly by hepatic histology and serum alanine aminotranferease and aspartate aminotransferase measurement.Proliferating cell nuclear antigen was used to evaluate the effect of baicalein in promoting hepatocyte proliferation.Serum interleukin(IL)-6,IL-1β and tumor necrosis factor-α(TNF-α) levels were measured by enzyme-linked immunosorbent assay and liver IL-6,TNF-α,transforming growth factor-α(TGF-α),hepatocyte growth factor(HGF) and epidermal growth factor(EGF) genes expression were determined by quantitative real-time polymerase chain reaction.RESULTS:CCl4-induced acute liver failure model offers a survival benefit in baicalein-treated mice.The data indicated that the mRNA levels of IL-6 and TNF-α significantly increased within 12 h after CCl 4 treatment in baicalein administration groups,but at 24,48 and 72 h,the expression of IL-6 and TNF-α was kept at lower levels compared with the control.The expression of TGF-α,HGF and EGF was enhanced dramatically in baicalein administration group at 12,24,48 and 72 h.Furthermore,we found that baicalein significantly elevated the serum level of TNF-α and IL-6 at the early phase,which indicated that baicalein could facilitate the initiating events in liver regeneration.CONCLUSION:Baicalein may be a therapeutic candidate for acute liver injury.Baicalein accelerates liver regeneration by regulating TNF-α and IL-6 mediated pathways.

Simultaneous determination of amino acids in different teas using supercritical fluid chromatography coupled with single quadrupole mass spectrometry

Tea is a widely consumed beverage and has many important physiological properties and potential health benefits. In this study, a novel method based on supercritical fluid chromatography coupled with mass spectrometry (SFC-MS) was developed to simultaneously determine 11 amino acids in different types of tea (green teas, Oolong tea, black tea and Pu-erh tea). The separation conditions for the analysis of the selected amino acids including the column type, temperature and backpressure as well as the type of additive, were carefully optimized. The best separation of the 11 amino acids was obtained by adding water (5%, v/v) and trifluoroacetic acid (0.4%, v/v) to the organic modifier (methanol). Finally, the developed SFC-MS method was fully validated and successfully applied to the determination of these amino acids in six different tea samples. Good linearity (r ≥ 0.993), precision (RSDs≤ 2.99%), accuracy (91.95%-107.09%) as well as good sample stability were observed. The limits of detection ranged from 1.42 to 14.69 ng/mL, while the limits of quantification were between 4.53 and 47.0 ng/mL. The results indicate that the contents of the 11 amino acids in the six different tea samples are greatly influenced by the degree of fermentation. The proposed SFC-MS method shows a great potential for further investigation of tea varieties.

Quality analysis of commercial samples of Ziziphi spinosae semen(suanzaoren) by means of chromatographic fingerprinting assisted by principal component analysis

Due to the scarcity of resources of Ziziphi spinosae semen （ZSS）, many inferior goods and even adulterants are generally found in medicine markets. To strengthen the quality control, HPLC fingerprint common pattern established in this paper showed three main bioactive compounds in one chromatogram simultaneously. Principal component analysis based on DAD signals could discriminate adulterants and inferiorities. Principal component analysis indicated that all samples could be mainly regrouped into two main clusters according to the first principal component （PC1, redefined as Vicenin II） and the second principal component （PC2, redefined as zizyphusine）. PC1 and PC2 could explain 91.42%of the variance. Content of zizyphusine fluctuated more greatly than that of spinosin, and this result was also confirmed by the HPTLC result. Samples with low content of jujubosides and two common adulterants could not be used equivalently with authenticated ones in clinic, while one reference standard extract could substitute the crude drug in pharmaceutical production. Giving special consideration to the well-known bioactive saponins but with low response by end absorption, a fast and cheap HPTLC method for quality control of ZSS was developed and the result obtained was commensurate well with that of HPLC analysis. Samples having similar fingerprints to HPTLC common pattern targeting at saponins could be regarded as authenticated ones. This work provided a faster and cheaper way for quality control of ZSS and laid foundation for establishing a more effective quality control method for ZSS.

Lithium promotes proliferation and suppresses migration of Schwann cells

Schwann cell proliferation,migration and remyelination of regenerating axons contribute to regeneration after peripheral nervous system injury.Lithium promotes remyelination by Schwann cells and improves peripheral nerve regeneration.However,whether lithium modulates other phenotypes of Schwann cells,especially their proliferation and migration remains elusive.In the current study,primary Schwann cells from rat sciatic nerve stumps were cultured and exposed to 0,5,10,15,or 30 mM lithium chloride(LiCl)for 24 hours.The effects of LiCl on Schwann cell proliferation and migration were examined using the Cell Counting Kit-8,5-ethynyl-2′-deoxyuridine,Transwell and wound healing assays.Cell Counting Kit-8 and 5-ethynyl-2′-deoxyuridine assays showed that 5,10,15,and 30 mM LiCl significantly increased the viability and proliferation rate of Schwann cells.Transwell-based migration assays and wound healing assays showed that 10,15,and 30 mM LiCl suppressed the migratory ability of Schwann cells.Furthermore,the effects of LiCl on the proliferation and migration phenotypes of Schwann cells were mostly dose-dependent.These data indicate that lithium treatment significantly promotes the proliferation and inhibits the migratory ability of Schwann cells.This conclusion will inform strategies to promote the repair and regeneration of peripheral nerves.All of the animal experiments in this study were ethically approved by the Administration Committee of Experimental Animal Center of Nantong University,China(approval No.20170320-017)on March 2,2017.

Discoursing on Soxhlet extraction of ginseng using association analysis and scanning electron microscopy

Soxhlet extraction is a common method of sample preparation. However, there has been no discussion about the efficiency of Soxhlet extraction from different batches and the factors that cause content fluctuation. In this study, Panax ginseng was selected as a model sample. Soxhlet extraction by means of a water bath, which has always been neglected, was identified as a novel key factor in the poor repeat- ability in different batches of Soxhlet extraction, as it can affect the siphon times and reflux time, which have been positively correlated with the ginsenoside contents. By substituting round bottom flasks in the same column, the relative standard deviation of the most fluctuated compound, ginsenoside Rbl, was decreased from 24.6% to 5.02%. Scanning electron microscopy analysis confirmed that the breakdown of the surface of the ginseng powder in the Soxhlet extraction led to a better dissolution of ginsenosides, indicating that chloroform may promote the extraction of ginsenosides by disrupting the cell structure. Moreover, 70% methanol was regarded as the better solvent for extracting the ginsenosides. Overall, this work offers a practical and effective protocol for improving the accuracy and repeatability of Soxhlet extraction methodology for ginsenosides and other analytes.

Comparative permeability of three saikosaponins and corresponding saikogenins in Caco-2 model by a validated UHPLC-MS/MS method

Saikosaponins(SSs)are the main active components extracted from Bupleuri Radix(BR)which has been used as an important herbal drug in Asian countries for thousands of years.It has been reported that the intestinal bacteria plays an important role in the in vivo disposal of oral SSs.Although the deglycosylated derivatives(saikogenins,SGs)of SSs metabolized by the intestinal bacteria are speculated to be the main components absorbed into the blood after oral administration of SSs,no studies have been reported on the characteristics of SGs for their intestinal absorption,and those for SSs are also limited.Therefore,a rapid UHPLC-MS/MS method was developed to investigate and compare the apparent permeability of three common SSs(SSa,SSd,SSb2)and their corresponding SGs(SGF,SGG,SGD)through a bidirectional transport experiment on Caco-2 cell monolayer model.The method was validated according to the latest FDA guidelines and applied to quantify the six analytes in transport medium samples extracted via liquid-liquid extraction(LLE).The apparent permeability coefficient(Papp)determined in this study indicated that the permeability of SGs improved to the moderate class compared to the corresponding parent compounds,predicting a higher in vivo absorption.Moreover,the efflux ratio(ER)value demonstrated an active uptake of SSd and the three SGs,while a passive diffusion of SSa and SSb2.

Molecular Docking and 3D-QSAR Studies on a Series of Fused Heterocyclic Amides as B-Raf Inhibitors

B-Raf has been identified as promising targets for novel anticancer agents. To further explore the interactions between small molecules and B-Raf, and to elucidate structural characteristics that influence the B-Raf kinase activity, molecular docking and three-dimensional quantitative structure-activity relationship（3D-QSAR） studies were performed on a dataset of 75 Type Ⅱ inhibitors. Molecular docking was applied to explore the detailed binding process between the inhibitors and B-Raf kinase in its DFG-out inactive conformation. Based on the conformations obtained by molecular docking strategy, 3D-QSAR models, including comparative molecular field analysis（CoMFA） and comparative molecular similarity indexes analysis（CoMSIA）, were constructed. The established 3D-QSAR models show significant statistical quality and satisfactory predictive ability, with high q^2 and r^2 values： CoMFA model（q^2= 0.759, r^2 = 0.922）, and CoMSIA model（q^2 = 0.685, r^2 = 0.945）. The systemic external validation indicated that both CoMFA and CoMSIA models were quite robust and possess high predictive abilities with r^2 pred values of 0.633 and 0.708, respectively. Several key structural features accounting for the inhibitory activities of these compounds were discussed based on the 3D contour maps generated by the CoMFA and CoMSIA models, which were in good accordance with the docking results. These theoretical results rendered by 3D-QSAR models along with the docking may provide a useful reference for understanding the action mechanism and designing novel potential B-Raf inhibitors.

Determination of torasemide in human plasma and its bioequivalence study by high-performance liquid chromatography with electrospray ionization tandem mass spectrometry

A sensitive and selective method using high-performance liquid chromatography coupled with elec- trospray ionization tandem mass spectrometry （HPLC-ESI-MS） to determine the concentration of tor- asemide in human plasma samples was developed and validated. Tolbutamide was chosen as the internal standard （IS）. The chromatography was performed on a GI Sciences Inertsil ODS-3 column （100 mm× 2.1 mm i.d., 5.0 μm） within 5 min, using methanol with 10 mM ammonium formate （60：40, v/ v） as mobile phase at a flow rate of 0.2 mL/min. The targeted compound was detected in negative io- nization at m/z 347.00 for torasemide and 269.00 for IS. The linearity range of this method was found to be within the concentration range of 1-2500 ng/mL （r=0.9984） for torasemide in human plasma. The accuracy of this measurement was between 94.05% and 103.86%. The extracted recovery efficiency was from 84.20% to 86.47% at three concentration levels. This method was also successfully applied in pharmacokinetics and bioequivalence studies in Chinese volunteers.