Advance on inducing ferroptosis of tumor cells based on nanodelivery technology / 药学学报

At present, cancer is still one of the most serious threats to human health. Despite the wide application of multiple cancer therapies in clinical practice, the therapeutic effects of most cancers are still far from satisfactory. In recent years, the discovery of regulated cell death may be a good first step on the road to treat cancer. Ferroptosis is triggered by lipid peroxidation of unsaturated fatty acids in cell membrane catalyzed by iron ion. It has been widely concerned as an emerging target for cancer therapy. With the booming of biomedical nanotechnology, ferroptosis as an emerging therapeutic target has attracted extensive attention. Here, we review the advance on the intersection of ferroptosis and biomedical nanotechnology. First, the research background of ferroptosis and nano-preparation as well as the feasibility of ferroptosis-based nano-drug delivery systems (nano-DDS) for cancer treatment are presented and analyzed. Then, the strategies for inducing ferroptosis based on nano-DDS are summarized, mainly including: the promotion of Fenton reaction, the inhibition of glutathione peroxidase 4 (GPX-4) and the restriction of the cysteine-glutamate exchange transporter (system Xc-). Furthermore, the combination therapy strategies based on biomedical nanotechnology induced ferroptosis are also discussed. Finally, we shine the spotlight on the prospects and challenges of ferroptosis-based nanotherapeutics in clinical application.

Normalization of the ratio of nitric oxide and peroxynitrite by promoting eNOS dimer activity is a new direction for diabetic nephropathy treatment / 生理学报

Diabetic nephropathy is a microvascular complication of diabetes. Its etiology involves metabolic disorder-induced endothelial dysfunction. Endothelium-derived nitric oxide (NO) plays an important role in a number of physiological processes, including glomerular filtration and endothelial protection. NO dysregulation is an important pathogenic basis of diabetic nephropathy. Hyperglycemia and dyslipidemia can lead to oxidative stress, chronic inflammation and insulin resistance, thus affecting NO homeostasis regulated by endothelial nitric oxide synthase (eNOS) and a conglomerate of related proteins and factors. The reaction of NO and superoxide (O2.-) to form peroxynitrite (ONOO-) is the most important pathological NO pathway in diabetic nephropathy. ONOO- is a hyper-reactive oxidant and nitrating agent in vivo which can cause the uncoupling of eNOS. The uncoupled eNOS does not produce NO but produces superoxide. Thus, eNOS uncoupling is a critical contributor of NO dysregulation. Understanding the regulatory mechanism of NO and the effects of various pathological conditions on it could reveal the pathophysiology of diabetic nephropathy, potential drug targets and mechanisms of action. We believe that increasing the stability and activity of eNOS dimers, promoting NO synthesis and increasing NO/ONOO- ratio could guide the development of drugs to treat diabetic nephropathy. We will illustrate these actions with some clinically used drugs as examples in the present review.

Probing the new strategy for the oral formulations of taxanes: changing the method with the situation / 中国天然药物

The first-generation taxanes (including paclitaxel and docetaxel) are widely used for the treatment of various cancers in clinical settings. In the past decade, a series of new-generation taxanes have been developed which are effective in the inhibition of tumor resistance. However, intravenous (i.v.) infusion is still the only route of administration, and may result in serious adverse reactions with respect to the utilization of Cremophor EL or Tween-80 as solvent. Besides, the dosing schedule is also limited. Therefore, oral administration of taxanes is urgently needed to avoid the adverse reactionss and increase dosing frequency. In this review, we first outlined the discovery and development of taxane-based anticancer agents. Furthermore, we summarized the research progress on the oral formulations of taxanes and proposed some thoughts on the future development of oral taxane formulations.

Improvement of in vitro dissolution and physical stability for spironolactone solid dispersion formulated with Soluplus / 药学学报

Spironolactone, a class II drug of the biopharmaceutics classification system, has low oral bioavailability due to poor solubility. Spironolactone solid dispersions were prepared using the solvent method in order to improve its aqueous solubility. Optimization studies of spironolactone solid dispersions were performed using in vitro dissolution tests. Differential scanning calorimetry, X-ray diffraction and Fourier transform infrared were used to investigate the physical state of the drug in carrier materials and to detect the possible interactions between the drug and carrier materials in the solid dispersions. In addition, stress tests were employed to elucidate the key factors which have influence on the stability of the spironolactone solid dispersions. Results showed that spironolactone in the solid dispersions formulated with Soluplus and HPMC-E5 were both in amorphous state and the hydrogen bonds between the drug and carrier materials were formed in the solid dispersion. Therefore, the in vitro dissolution of spironolactone was also significantly enhanced. Stress tests demonstrated that the physical stability of spironolactone solid dispersions prepared with Soluplus was greatly improved compared to those formulated with HPMC-E5. Thus, spironolactone solid dispersion formulated with Soluplus using the solvent method could be used to improve the in vitro dissolution and stability of poorly soluble drugs.

Real-time UV imaging of chloramphenicol intrinsic dissolution characteristics from ophthalmic in situ gel / 药学学报

In this paper, chloramphenicol was selected as a model drug to prepare in situ gels. The intrinsic dissolution rate of chloramphenicol from in situ gel was evaluated using the surface dissolution imaging system. The results indicated that intrinsic dissolution rate of chloramphenicol thermosensitive in situ gel decreased significantly when the poloxamer concentration increased. The addition of the thickener reduced the intrinsic dissolution rate of chloramphenicol thermosensitive gel, wherein carbomer had the most impact. Different dilution ratios of simulated tear fluid greatly affected gel temperature, and had little influence on the intrinsic dissolution rate of chloramphenicol from the thermosensitive in situ gel. The pH of simulated tear fluid had little influence on the intrinsic dissolution rate of chloramphenicol thermosensitive in situ gel. For the pH sensitive in situ gel, the dissolution rates of chloramphenicol in weak acidic and neutral simulated tear fluids were slower than that in weak alkaline simulated tear fluid. In conclusion, the intrinsic dissolution of chloramphenicol from in situ gel was dependent on formulation and physiological factors. With advantages of small volume sample required and rapid detection, the UV imaging method can be an efficient tool for the evaluation of drug release characteristics of ophthalmic in situ gel.

Preparation and characterization of dihydroartemisinin/ hydroxypropyl-beta-cyclodextrin inclusion complex / 药学学报

To optimize the preparation method of the complex of dihydroartemisinin (DHA) included by hydroxypropyl-beta-cyclodextrin (HP-beta-CD), the molar ratio of DHA and HP-beta-CD, inclusion temperature and inclusion time were optimized by the orthogonal design method with the inclusion drug yield and drug loading as the evaluation indexes. The IR spectrum, DSC and PXRD analyses were employed to characterize the complex and the molecular simulation was processed to investigate the tendency of complex formation. The optimized molar ratio of DHA and HP-beta-CD was 1 : 5, and the optimized preparation was performed under 50 degrees C for 1 h. The IR spectrum, DSC and PXRD analyses indicated the formation of the complex. The low binding free energy and the high solvent accessible surface obtained by molecular simulation showed that DHA could be included by HP-beta-CD and its solubility could be improved significantly. In conclusion, the optimized conditions for the preparation of DHA-HP-beta-CD complex provide a theoretical and experimental basis for further scale-up research.

Pharmaceutical evaluation of hydroxycamptothecin nanosuspensions with the action of inhibiting P-gp / 药学学报

Oral hydroxycamptothecin nanosuspension (HCPT-Nano) with high supersaturated dissolution level, high permeation and well physical stability, was manufactured by microprecipitation-high press homogenization method. Its pharmaceutical properties were investigated, such as size and distribution, zeta potential, particle shape, physical existence condition, supersaturated dissolution level and so on. Particle size was measured by laser diffraction, and the mean diameters before and after lyophilization were 138 +/- 11.72 nm and 175 +/- 12.74 nm, respectively, for HCPT-Nano. Zeta potentials of HCPT-Nano was over -20 mV. The nanoparticles, being observed by transmission electron microscopy (TEM), were claviform or column in shape. DSC and X-ray diffraction revealed that HCPT existed in the form of crystal for HCPT-Nano. And HCPT-Nano could maintain higher supersaturated dissolution level for long time. So it supplied the possibility of improving oral bioavailability of HCPT when combining together admoveatur of P-gp inhibitor, CsA.

Preparation of in situ gel systems for the oral delivery of ibuprofen and its pharmacokinetics study in beagle dogs / 药学学报

The in situ gel systems can form gel in situ after administration to achieve sustained release, thus provides a promising strategy for drug delivery systems. The aim of this study was to design and prepare in situ gel systems for the oral delivery of ibuprofen (IBU-ISG) and study its pharmacokinetics in Beagle dogs. The characteristics of the basic material of gellan gum (Kelcogel, Kel) and sodium alginate (Manugel, M) were studied through investigating the complex viscosity of the Kel or M solution with or without different concentrations of calcium ion or sodium citrate to ascertain the amount range of the excipients. The measurement of complex viscosity of the solution (0. 5% Kel and 1% M) with different concentrations of sodium citrate and calcium ion was carried out to select the suitable proportion of calcium ion and sodium citrate. The formulation of binary IBU-ISG was optimized by monitoring the complex viscosity before gelling in vitro release property. The optimized formulation contains 1.0% sodium alginate, 0.5% gellan gum, 0. 21% sodium citrate and 0.056% calcium chloride. A single oral dose of IBU-ISG and reference formulation (IBU suspension) were given to each of the 6 healthy Beagle dogs, ibuprofen in plasma at different sampling times was determined by RP-HPLC. The pharmacokinetics parameters in 6 Beagle dogs were calculated. The Tmax of IBU-ISG and reference formulation were (1.8 +/- 0.6) and (0.4 +/- 0. 1) h. The Cmax values were (29.2 +/- 7.6) and (37.8 +/- 2.2) microg x mL(-1). The T(1/2) were (2.3 +/- 0.5) and (2.0 +/- 0.9) h, and the AUC(0-t) were (131.0 +/- 38.6) and (117.3 +/- 23.1) microg x mL(-1) x h, respectively. The binary IBU-ISG was successfully prepared.

Percutaneous absorption of meloxicam patches in hairless mouse / 药学学报

Meloxicam concentration in skin was determined following topical administration of meloxicam patches in hairless mouse. Samples were analysized by HPLC coupled with microdialysis sampling technique, in which in vivo recovery of probe was characterized by the retrodialysis method. It was indicated that the in vivo recovery of the probe was 14.0%. The range of steady state concentration of meloxicam in dialysate was 24-50 ng x mL(-1), and that was 170-360 ng x mL(-1) in the hairless mouse skin. Steady state concentration of meloxicam was reached shortly after the application of meloxicam patches, which was maintained during the period of experiment.

A new method for quantitative assessment of mechanisms of partitioning and absorption of drugs: linear solvation energy relationships / 药学学报

Linear solvation energy relationships are of a great value in investigating quantitative structure-retention relationship and quantitative structure-activity relationship, and predicting chromatographic retention indices of drugs. Several quantitative relationships in different in vitro biomembrane-mimetic models between retention factors and molecular descriptors have been established successfully and used to clarify drug-membrane interaction mechanisms. Quantitative structure-activity relationships also have been established to predict drug intestinal absorption, permeation of skin and blood-brain barrier. This review focused on the significance and widely application of linear solvation energy relationships in quantitative assessment for mechanisms of partitioning and absorption of drugs. The discrepancy and limits of linear solvation energy relationships were also discussed, which gives us a better insight into investigation of partitioning and absorption of drugs.

Studies on preparation of sustained-release Shuxiong formulation, a traditional Chinese medicine compound recipe, using time-controlled release techniques / 中国中药杂志

<p><b>OBJECTIVE</b>To prepare a sustained-release formulation of traditional Chinese medicine compound recipe by adopting time-controlled release techniques.</p><p><b>METHOD</b>Shuxiong tablets were chosen as model drug. The prescription and technique of core tablets were formulated with selecting disintegrating time and swelling volume of core tablets in water as index. The time-controlled release tablets were prepared by adopting press-coated techniques, using PEG6000, HCO and EVA as coating materials. The influences of compositions, preparation process and dissolution conditions in vitro on the lag time (T(lag)) of drug release were investigated.</p><p><b>RESULT</b>The composition of core tablets was as follow: 30% of drug, 50% MCC and 20% CMS-Na. The T(lag) of time-controlled release tablets was altered remarkably by PEG6000 content of the outer layer, the amount of outer layer and hardness of tablet. The viscosity of dissolution media and basket rotation had less influence on the T(lag) but more on rate of drug release.</p><p><b>CONCLUSION</b>The core tablets pressed with the optimized composition had preferable swelling and disintegrating properties. The shuxiong sustained-release formulations which contained core tablet and two kinds of time-controlled release tablets with 3 h and 6 h of T(lag) could release drug successively at 0 h, 3 h and 6 h in vitro. The technique made it possible that various components with extremely different physicochemical properties in these preparations could release synchronously.</p>

Preparation of Shuxiong micropellets by centrifugal granulation technology / 中国中药杂志

<p><b>OBJECTIVE</b>To prepare shuxiong micropellets.</p><p><b>METHOD</b>Shuxiong micropellets were prepared by using a centrifugal granulator. The formulation composition and process factors were optimized investigated by adopting several indices such as size distribution, repose angle, bulk density and friability as indexes.</p><p><b>RESULT</b>The optimal process parameters were as follows. The ratio of fine intermediate product and MCC was 3:1 (w/w), the adhesive agent was 3% HMPC solution, the rotating rate of plate was 200 r x min(-1), the blower rate was 15 x 20 L x min(-1), the rate of air flow was 15 L x min(-1), the spray air pressure was 0.5 MPa, the rotating of spray solution pump was 5-25 r x min(-1) and the rotating rate of powder feed machine was 5-25 r x min(-1).</p><p><b>CONCLUSION</b>Under the optimal conditions, micropellets prepared by using centrifugal granulator hadpossessed prefect shape and surface characteristics and the yield of shuxiong pellets was 90.5%.</p>

The solubilization effect of 2-hydroxypropyl-beta-cyclodextrin on paeonolum / 中国中药杂志

<p><b>OBJECTIVE</b>To study the solubilization effect of 2-hydroxypropyl-beta-cyclodextrin(HPCD) on paeonolum at various pH value.</p><p><b>METHOD</b>Phase-solubility method was adopted to study the solubilization effect at 25 degrees C and UV spectrohotometer was used to determine paeonolum content.</p><p><b>RESULTS</b>The apparent solubility of paeonolum was significantly enhanced by increased HPCD concentration. The apparent stability constant of paeonolum compounds was calculated up to 1 425 in which pH was 3 and HPCD concentration was 133.33 mmol x L(-1). The solubility of paeonolum came up to 10 mg x mL(-1).</p><p><b>CONCLUSION</b>HPCD is an ideal solubilizer for paeonolum.</p>

Comparative study of lipophilicity from immobilized artificial chromatography and n-octanol/buffer systems / 药学学报

<p><b>AIM</b>To compare lipophilicity measuring scale stemmed from immobilized artificial membrane chromatography and n-octanol/buffer systems.</p><p><b>METHODS</b>A test set consisted of 27 structurally diverse compounds. The lipophilicity of these were evaluated by both immobilized artificial membrane chromatography (IAMC) and n-octanol/buffer systems, which were expressed as lg kIAM and lg DO/W,7.4, respectively.</p><p><b>RESULTS</b>With regard to each individual group, good correlation coefficient (r2) over 0.81 was obtained (0.82 for acid; 0.88 for neutral, 0.81 for base and 0.92 for ampholyte, respectively). However, a smaller r2 (0.62) was acquired for all compounds studied than that of each individual group.</p><p><b>CONCLUSION</b>IAMC and n-octanol/buffer systems were shown to be different in lipophilicity.</p>

Evaluation of interaction between drugs and ordered phospholipid membrane by immobilized artificial membrane chromatography / 药学学报

<p><b>AIM</b>To investigate the interaction between drugs and ordered phospholipid membrane using immobilized artificial membrane chromatography (IAMC).</p><p><b>METHODS</b>IAMC was used to determine the interaction drugs with phospholipid membrane, expressed as membrane affinity (lg kIAM). An n-octanol/buffer system was also employed as the reference hydrophobicity (lg Do/w,7.4).</p><p><b>RESULTS</b>Within the range of used acetonitrile percentages (phi) 0-30% in mobile phase, retention index (lg kIAM) showed excellent correlation with phi. Intercepts of fitted straight lines between lg kIAM and phi were comparable but slopes were much different for the three organic modifiers (acetonitrile, ethanol and methanol). Effects by adding CH2 substituent on lipophilicity difference (delta lg kIAM and delta lg Do/w,7.4) were similar for p-hydroxyl benzoic methyl ester to butyl ester, whereas different for p-hydroxylbenzoic acid to methyl ester.</p><p><b>CONCLUSION</b>IAMC system is a convenient, efficient and rapid tool for determining membrane interaction.</p>