Background Conventional chemotherapy agent such as doxorubicin (DOX) is of limited clinical use because of its inherently low selectivity, which can lead to systemic toxicity in normal healthy tissue. Methods A pH stimuli-sensitive conjugate based on polyethylene glycol (PEG) with covalently attachment doxorubicin via hydrazone bond (PEG-hyd-DOX) was prepared for tumor targeting delivery system. While PEG-DOX conjugates via amid bond (PEG-ami-DOX) was synthesized as control. Results The synthetic conjugates were confirmed by proton nuclear magnetic resonance (NMR) spectroscopy, the release profile of DOX from PEG-hyd-DOX was acid-liable for the hydrazone linkage between DOX and PEG, led to different intracellular uptake route; intracellular accumulation of PEG-hyd-DOX was higher than PEG-ami-DOX due to its pH-triggered profile, and thereby more cytotoxicity against MCF-7, MDA-MB-231 (breast cancer models) and HepG2 (hepatocellular carcinoma model) cell lines. Following the in vitro results, we xenografted MDA-MB-231 cell onto SCID mice, PEG-hyd-DOX showed stronger antitumor efficacy than free DOX and was tumor-targeting. Conclusions Results from these in vivo experiments were consistent with our in vitro results; suggested this pH-triggered PEG-hyd-DOX conjugate could target DOX to tumor tissues and release free drugs by acidic tumor environment, which would be potent in antitumor drug delivery.
Abstract Background: Bone is a frequent site of metastasis in lung cancer patients. So far, the treatment in bone metastasis of lung cancer still has not achieved any satisfactory effects in clinic. In this paper, alendronate (ALN) was selected to be connected with PAMAM via pH sensitive cis-aconitine anhydride (CA) to prepare bone-targeted micelle (DTX@ALN-PAMAM) to treat bone metastasis of lung cancer. Results: It was discovered that DTX@ALN-PAMAM released docetaxel (DTX) and ALN in pH-dependent manner. Besides, DTX@ALN-PAMAM showed high bind affinity with bone matrix, and quickly desorbed from bone matrix in weak acidic medium due to the rupture of cis-aconitamide bond between ALN and PAMAM. The in vitro results showed that DTX@ALN-PAMAM significantly enhanced the antitumor activity of DTX and decreased bone resorption through inhibiting the formation of osteoclasts in in-vitro 3D bone metastases model of lung cancer. In addition, DTX@ALN-PAMAM accumulated at bone metastases tissues for a relatively long time in tumor-bearing nude mice, which significantly reduced the bone resorption, relieved the pain response of tumor-bearing nude mice, and delayed the growth of bone metastases. Eventually, the therapeutic effect of DTX was improved on bone metastases of lung cancer. Conclusion: ALN modified PAMAM is a new and an effective platform for the treatment of bone metastasis of lung cancer.
Abstract Background At present, patients with myocardial infarction remain an increased risk for myocardial ischemia/reperfusion injury (MI/RI). There lacks effectively method to treat MI/RI in clinic. For the treatment of MI/RI, it is still a bottleneck to effectively deliver drug to ischemic myocardium. In this paper, a regulatory T cells (Tregs) biomimetic nanoparticle (CsA@PPTK) was prepared by camouflaging nanoparticle with platelet membrane. Results CsA@PPTK actively accumulated in ischemic myocardium of MI/RI mice. CsA@PPTK significantly scavenged reactive oxygen species (ROS) and increased the generation of Tregs and the ratio of M2 type macrophage to M1 type macrophage in ischemic myocardium. Moreover, CsA@PPTK significantly attenuated apoptosis of cardiomyocytes and reduced the infarct size and fibrosis area in ischemic myocardium. CsA@PPTK markedly decreased the protein expression of MMP-9 and increased the protein expression of CX43 in ischemic myocardium tissue. Subsequently, the remodeling of the left ventricle was significant alleviated, and heart function of MI/RI mice was markedly improved. Conclusion CsA@PPTK showed significant therapeutic effect on MI/RI, and it has great potential application in the treatment of MI/RI. Graphical Abstract
Abstract Background and Purpose Liver fibrosis is a wound‐healing reaction which is the main cause of chronic liver diseases worldwide. The activated hepatic stellate cell (aHSC) is the main driving factor in the development of liver fibrosis. Inhibiting autophagy of aHSC can prevent the progression of liver fibrosis, but inhibiting autophagy of other liver cells has opposite effects. Hence, targeted inhibition of autophagy in aHSC is quite necessary for the treatment of liver fibrosis, which prompts us to explore the targeted delivery system of small molecule autophagy inhibitor hydroxychloroquine (HCQ) that can target aHSC and alleviate the liver fibrosis. Methods The delivery system of HCQ@retinol‐liposome nanoparticles (HCQ@ROL‐LNPs) targeting aHSC was constructed by the film dispersion and pH‐gradient method. TGF‐β‐induced HSC activation and thioacetamide (TAA)‐induced liver fibrosis mice model were established, and the targeting ability and therapeutic effect of HCQ@ROL‐LNPs in liver fibrosis were studied subsequently in vitro and in vivo. Results HCQ@ROL‐LNPs have good homogeneity and stability. They inhibited the autophagy of aHSC selectively by HCQ and reduced the deposition of extracellular matrix (ECM) and the damage to other liver cells. Compared with the free HCQ and HCQ@LNPs, HCQ@ROL‐LNPs had good targeting ability, showing enhanced therapeutic effect and low toxicity to other organs. Conclusion Construction of HCQ@ROL‐LNPs delivery system lays a theoretical and experimental foundation for the treatment of liver fibrosis and promotes the development of clinical therapeutic drugs for liver diseases.
A rapid, sensitive HPLC-MS/MS method was established and validated to assay the concentration and pharmacokinetic profile of MT502, a promising hypnotic drug. The plasma sample was treated by a liquid-liquid extraction and separated on a kromasil C18 column at an isocratic flow rate of 0.3 mL/min using methanol and 0.1% formic acid in water (75:25, v/v) as mobile phase. The mass spectrometric detection was carried out using a triple-quadrupole system via positive electrospray ionization. Multiple reaction monitoring was used for quantitation of m/z transitions from 261 to 188 for MT502 and from 247 to 188 for MT501 (internal standard). Good linearity was achieved over the concentration range of 1-1000 ng/mL and 10-5000 ng/mL with lower limit of quantification of 0.30 and 0.80 ng/mL. The intra- and inter-day precisions, accuracy, recovery and stability were satisfactory for the concentration test. The above method can be used for a pharmacokinetic study at doses of 1, 5 and 20 mg/kg. Results indicated that MT502 had rapid absorption, rapid elimination and linear pharmacokinetic properties within the range of the tested intragastric dose. This developed HPLC-MS/MS method was successfully applied to a pharmacokinetic study of MT502 for the first time and was demonstrated to be simple and sensitive.
Genistein (4′,5,7-trihydroxyisoflavone), a naturally occurring phenolic compound, possesses well-known preventive activity in breast and prostate cancer, cardiovascular diseases, and postmenopausal problems. The aim of this study is to investigate the distribution and dose-dependent absorption, metabolism, and excretion of genistein in rats. Genistein was orally administered to rats at different doses. At various time intervals, blood, bile, and urine samples were collected and incubated with glucuronidase to hydrolyze the glucuronidated genistein. Genistein was detected by HPLC. High levels of glucuronidated genistein were detected in the plasma, bile, and urine after genistein administration. When genistein was administered to rats at 6.25, 12.5, and 50 mg·kg−1 doses, the AUC(0−t) values for genistein were 23.5, 80.9, and 177.9 mg·min·L−1; the oral absolute bioavailabilities were 21.9, 33.5, and 19.0%; the AUC(0−t) values of glucuronidated genistein were 173.8, 470.7, and 1721.2 mg·min·L−1, respectively. The cumulative biliary excretion of genistein respective to each dose was 42.6 ± 6.5, 75.2 ± 18.9, and 126.6 ± 34.8 μg; the cumulative biliary excretion of glucuronidated genistein was 108.5 ± 35.2, 423.5 ± 158.3, and 853.7 ± 320.8 μg for each dose, respectively. The cumulative urinary excretion of genistein was 34.8 ± 10.8, 187.3 ± 67.0 and 213.6 ± 30.6 μg for each dose, respectively; the cumulative levels of glucuronidated genistein excreted in the urine were 217.8 ± 52.1, 583.1 ± 106.9, and 1108.4 ± 88.1 μg, respectively. These results indicated that at high doses absorption, biotransformation, and excretion of genistein occurred in a nonlinear dose-dependent manner. Therefore, the results of these pharmacokinetic studies raise important questions about the therapeutic significance of consuming large quantities of genistein, genistein analogues, or soy-based neutraceuticals.
A new efficient method for the synthesis of linear furocoumarins by a Nef reaction and intramolecular cyclocondensation in one pot results in the construction of a benzofuran ring. This method provides a new strategy to furnish the benzofuran framework easily, and also allows the convenient synthesis of furocoumarin derivatives with different substituents on the coumarin ring by a subsequent Pechmann reaction. This strategy has also been applied to the preparation of four additional benzofuran derivatives.
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