Latest ArticlesIn this study, the effects of honokiol (HN) treatment for 24 h on lipid synthesis was examined in HepG2 cells. The parameters include intracellular lipid droplet and the expression of SREBP-1c and PNPLA3, glucose uptake, and oxidative stress including the expression of CYP2E1 and CYP4A in normal, TO901317 (TO)- and oleic acid (OA)-treated HepG2 cells. The lipid droplets were detected by oil red O staining. The glucose uptake was measured by fluorescence spectrophotometry using[2-(N-(7-nitrobenz-2-oxa-1, 3-diazol-4-yl) amino)-2-deoxyglucose, 2-NBDG] as probe. The expression levels of target genes were detected by quantitative PCR and Western blot. The results showed that:① TO (5 μmol·L-1) and OA (0.5 mmol·L-1) treatment increased the levels of intracellular lipid accumulation and the mRNA and protein expression of SREBP-1c and PNPLA3. After HN (10, 20, 40 μmol·L-1) treatment for 24 h, the lipid accumulation and the expression of SREBP-1c and PNPLA3 were all decreased in the tested cells. ② OA treatment significantly suppressed glucose uptake, while HN treatment dose-dependently increased the glucose uptake in OA-treated cells. ③ Compared with control group, CYP2E1 protein level significantly decreased in the three tested cells, and CYP4A protein level significantly decreased only in OA-treated cells following HN treatment. The above results suggest that HN may attenuate lipid accumulation by suppressing the expression of SREBP-1c and PNPLA3, and reduce lipid peroxidation and insulin resistance by down-regulation of the protein levels of CYP2E1 and CYP4A in HepG2 cells with steatosis.
As an important drug carrier, liposome has the advantages of high biocompatibility and low immunogenicity. It has been widely used in the field of drug delivery, especially the targeted treatment of tumors. However, traditional liposomes are composed of flowing dynamic phospholipid membranes, which are easy to fuse together, resulting in aggregation and drug leakage. In addition, the lower degree of polyethylene glycol (PEG) modification also limits the targeted delivery performance of the vector in vivo. In view of the problems, a nanoparticle-targeted drug delivery system combining the inorganic carrier calcium phosphate with liposomes was designed, namely lipid calcium phosphate (LCP). Using doxorubicin (DOX) as a model drug, doxorubicin-loaded lipid calcium phosphate nanoparticles (DOX/LCP) were prepared by reverse microemulsion method, and the preparation conditions were investigated. The structure and morphology of calcium phosphate cores were observed by infrared spectroscopy, EDS spectroscopy, and transmission electron microscopy. The particle size, encapsulation efficiency, drug loading, stability and release behavior in vitro of DOX/LCP were investigated. Confocal microscopy and flow cytometry were used to qualitatively and quantitatively evaluate the uptake of DOX in drug-resistant tumor cell line MCF-7/DOX by LCP, respectively, and the thiazolium MTT colorimetric method was used to examine its cytotoxicity. LCP exhibited a typical core-shell structure with good size uniformity and dispersibility. The particle size was in (48.6 ±3.9) nm, the potential was in (-12.1 ±1.2) mV, and the encapsulation efficiency was above 80%. Moreover, it has a good stability in simulated plasma. In vitro release of LCP had a significant pH dependence. When the pH of the environment was 7.4, the cumulative release within 24 hours was less than 20%; as the pH of the release medium decreases, the release rate of DOX/LCP was accelerated gradually. Accumulated release over 24 hours exceeded 90% in the pH 4.5 medium. LCP significantly promoted the uptake and accumulation of DOX by drug-resistant cells, and the inhibition rate of drug-resistant tumors was significantly increased in vitro. The half maximal inhibitory concentrations (IC50) of LCP/DOX and free DOX were 4.6 and 11.8 μg·mL-1, respectively, and there was a significant difference between the two groups (P < 0.05). In summary, the LCP prepared in this study had a small particle size, high encapsulation efficiency and good stability. It had environmental responsiveness and potential inhibition of tumor drug resistance, which suggests a potential in the clinical application.
Oxcarbazepine (OXC) is a common antiepileptic drugs. In this study, one hundred and eighty four epilepsy patients with 196 observations of oxcarbazepine's active metabolite, 10, 11-dihydro-10-monohydroxy carbazepine (MHD) were collected prospectively from routine clinical monitoring. Nonlinear mixed effect modeling was employed to develop a population pharmacokinetic model of oxcarbazepine in Chinese patients with epilepsy to investigate the impact of gender, age, weight, co-medications and genetic polymorphisms of UGT2B7 c.802T > C, ABCC2 c.1249G > A, ABCC 23972C > T on pharmacokinetic characteristics of OXC. The population estimate of apparent clearance (CL/F) and apparent volume of distribution (V/F) was 1.84 L·h−1 and 275 L, respectively. Gender and UGT2B7 c.802T > C affected the clearance rate of MHD significantly. The established model was:CL/F=1.84×0.848UGT2B7×1.17GENDER. Where the genotype of UGT2B7 c.802T > C was CC, UGT2B7=0, otherwise UGT2B7=1. When the patient was male, GENDER=1, otherwise GENDER=0. The final model was evaluated by normalized predictive distribution error (NPDE) and bootstrap method. The model was stable and reliable, which offers a powerful approach for rational use of OXC in epilepsy patients.
Flavonol glycoside is in clinical trials for treatment of hyperlipidemia. An accurate and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the simultaneous determination of flavonol glycoside (M0), aglycone (M1) and glucuronide conjugate (M2) in rat plasma. d6-Flavonol glycoside was used as internal standard (IS). After extraction from the plasma by protein precipitation, the analytes and internal standard were separated on a XDB C18 column (50 mm×4.6 mm, 1.8 μm) using a gradient elution procedure. The mobile phase consisted of methanol and water (0.2% formic acid) at a flow rate of 0.6 mL·min-1. The total run time was 4.5 min. Positive electrospray ionization was performed using multiple reaction monitoring (MRM) with transitions of m/z 461.3 → m/z 299.1 for M0, m/z 299.1 → m/z 283.1 for M1, m/z 475.0 → m/z 299.1 for M2, and m/z 467.3 → m/z 305.1 for d6-flavonol glycoside. The method was validated and successfully applied to the pharmacokinetics study of flavonol glycoside in SD rats which were given flavonol glycoside (30 mg·kg-1) by gavage. The Cmax of M0 is (341 ±106) ng·mL-1 and AUC0-t is (1 960 ±725) h·ng·mL-1, while the Cmax of M2 is (1 720 ±843) ng·mL-1and AUC0-t is (8 510 ±2 920) h·ng·mL-1. The results suggest that flavonol glycoside existed mainly in the form of M0 and M2 in rats. After flavonol glycoside being hydrolyzed by the intestinal flora, it was absorbed in the form of aglycone and further metabolized to M2 after the first-pass effect. In this paper, the main metabolites of flavonol glycoside in rat plasma were determined for the first time, which provided a basis for the design of clinical pharmacokinetic experiment.
This study was aimed to investigate the effects of six Schisandra lignans of Wuzhi tablet (WZ, a preparation of ethanol extract of Schisandra sphenanthera) on the pharmacokinetic process of digoxin (DG, a classical P-gp substrate) after intravenous and oral administration in rats. The effect of Schisandra lignans on the transportion of DG in Caco-2 cells was further elucidated. Our data showed that the plasma concentrations of DG were increased to different extent following co-administration of schisandrin A, schisandrin B, schisandrol B and schisantherin A, respectively. Schisandrol B showed the most potent effect among the six lignans. However, schisandrin C and schisandrol A showed little effect on pharmacokinetic of DG. Schisandrol B led to 99.0% (P < 0.05) and 109.2% (P < 0.05) increase in the AUC after orally or intravenously administered of DG, suggesting that co-administration of schisandrol B induced a more potent effect on increasing hepatic bioavailability of DG than that of intestinal. Furthermore, in vitro transport experiment showed that schisandrin A, schisandrin B, schisandrol B and schisantherin A inhibited P-gp-mediated efflux of DG, suggested that these lignans inhibited the P-gp-mediated efflux of DG. In conclusion, the exposure of DG in rats was increased when co-administered with Schisandra lignans, and schisandrol B showed the strongest effect. The dramatic increase in oral bioavailability of digoxin in the presence of schisandrol B may be due to the inhibition of hepatic/renal P-gp activity.
The study was designed to establish an LC-MS/MS method for the simultaneous determination of scutellarin and its major metabolite isoscutellarin in rat tissues and plasma, and to investigate the effect of different route of administration on the tissue distribution of scutellarin and its metabolite in rats. Rats were treated both intravenously and intragastrically with 20 and 80 mg·kg-1 scutellarin, respectively. Blood and tissues were collected at predetermined intervals. The concentrations of scutellarin and isoscutellarin were determined by a validated LC-MS/MS method. The method was linear in concentration ranges of 10.0/5.00 - 5 000/2 500 ng·mL-1 for scutellarin/isoscutellarin in the rat plasma and 30.0/15.0 - 10 000/5 000 ng·g-1 in tissues with acceptable accuracy and precision. Data obtained after an intravenous administration of scutellarin to rats showed that the drug was distributed predominantly into the small intestine, bladder and kidney. The exposures of the metabolite isoscutellarin in plasma and tissue were both less than 5%of the parent drug. After an intragastric administration, stomach wall and small intestine were the preferred sites for scutellarin disposition, followed by bladder, adrenal gland and lung at concentrations significantly higher than its plasma concentration. The plasma exposure of isoscutellarin was higher than that of the parent drug, but its tissue exposure was significantly lower than that of scutellarin. The method established in this study was successfully applied to characterization of the tissue profiles of scutellarin and its metabolite in rats. The route of administration has a marked impact on the disposition of scutellarin and its metabolite in rats. Ratios of the tissue to plasma concentrations after intragastric administration were obviously higher than those after intravenous administration. Scutellarin could pass the blood-brain barrier in a marked extent, but isoscutellarin was not detected in the rat brain, which may be attributed to the fact that scutellarin is a higher-affinity substrate for OATP than isoscutellarin.
Voltage-dependent anion channels (VDACs), which are located at the mitochondrial outer membrane, playing an important role in the regulation of mitochondrial energy metabolism and mitochondria- mediated apoptotic events, are considered as potential targets for tumor therapy. Studies have indicated that neurodegenerative diseases such as Alzheimer's disease (AD) generally lead to mitochondrial dysfunction. During this process, VDAC1, changing in expression, interacting with disease-related molecules, was involved in the occurrence and development of diseases. This review summarizes the characteristics and physiological functions of VDAC1, common important structural units and its role in apoptosis. The focus is on the research progress of VDAC1 in AD, as well as the effects in learning and memory related functions by modulating VDAC1 expression or function.
Three-dimensional (3D) printing technology is a rapid prototyping technology for designing 3D models with special shape and complex internal structure via computer-aided/controlled drawing and preparing. This technology displays the characteristics of flexible processing, rapid shaping, low operating cost and high reliability. 3D printing technology may provide new strategies and approaches for the generation of a variety of new drug delivery systems, which makes its application in pharmaceutics attractive. This review briefly introduces the process and feature of 3D printing technology in preparation field and mainly introduces the research progress in the design and engineering of related preparations in the aspects of rate-controlled drug release, time-controlled drug release and targeted drug release. The prospects and challenges of 3D printing technology in the formulation engineering are analyzed.
Phage display technology utilizes filamentous phage display proteins and polypeptides to extract a desired polypeptide or protein from a large number of variants. The antibody fragments screened and obtained by phage display library technology play an important role in disease diagnosis and treatment. This article briefly introduces the principles of phage display technology, summarizes the development of monoclonal antibodies, the development of antigenic microbial vaccines, and the application of peptide drugs. This review highlights the importance of phage display technology in the diagnosis and treatment of various human diseases such as cancer and autoimmune diseases etc.
IDO1 (indoleamine 2, 3-dioxygenase 1) is one of the most significant checkpoint in tumor immunology. Numerous studies indicates that IDO1 is abnormally expressed in breast cancer, colorectal cancer, liver cancer and other tumor tissues, participating in tumor immune escape through multiple pathways. This review is prepared to elucidate the biological function of IDO1, highlight its pivotal role in tumor evasion, and summarize IDO1 inhibitors in the clinical trials.