Phosphodiesterase 4 (PDE4) is an important member of the phosphodiesterase enzyme family that specifically catalyzes the hydrolysis of cyclic adenosine monophosphate (cAMP), activates the downstream phosphorylation cascade pathway by altering cAMP concentration, and is strongly associated with multiple diseases. Inhibition of PDE4 is clinically investigated as a therapeutic strategy in a broad range of disease areas, including respiratory system diseases, autoimmune disorders, central nervous system diseases, and dermatological conditions. However, the incidence of adverse reactions such as nausea and vomiting is relatively high in the marketed PDE4 inhibitors, which has stalled their clinical development. In this review, we provide an overview of the clinical progression and safety issues of the marketed PDE4 inhibitors. We also review the main causes underlying PDE4-mediated adverse effects by combining the structural analysis of the PDE4 protein, the mechanism of action of PDE4 inhibitors, and the related side effect mechanism research, aiming to provide a reference for the development of safe and effective PDE4 inhibitors.

The clinical tumor therapy was greatly challenged due to the complex characteristics of tumor microenvironment, however, which also provide arena for novel therapeutic strategies. In this study, poly(2-ethyl-2-oxazoline)-poly(lactic acid)-SS-poly(β-amino ester (PEOz-PLA-SS-PBAE) triblock copolymers with pH and GSH double response were synthesized, polymer micelles were prepared by thin film hydration method for loading of silybin to improve its antitumor activity. The critical micelle concentration was determined by pyrene fluorescence method as 1.8 μg·mL^-1. The particle size was 155.30 ±1.80 nm as determined by dynamic light scattering, with polydispersity index of 0.168 ±0.004. The drug loading and entrapment efficiency of the micelles were determined by HPLC as (5.48 ±0.04)% and (68.52 ±0.48)%, respectively. The in vitro drug release profiles showed that the micelles have low pH sensitivity and high GSH responsiveness, and exhibited sustained release profiles. The good biocompatibility of the material was proved by measuring the hemolysis rate and cytotoxicity of the blank micelle. The cytotoxicity and apoptosis rate of tumor cells showed that the drug loaded PEOz-PLA-SS-PBAE micelles had significant inhibitory effect and apoptosis-inducing effect on MDA-MB-231 cells. The results of wounding healing assay and Transwell invasion test showed that the drug loaded PEOz-PLA-SS-PBAE micelles could significantly inhibit the metastasis of MDA-MB-231 cells. The PEOz-PLA-SS-PBAE drug-loaded micelles prepared in this study have good inhibitory effect on tumor growth and anti-tumor metastasis in vitro, which lays the foundation for the further application of silybin.

Polysaccharide of Balanophora involucrata Hook. f. (BPS), the major component of Balanophora involucrata Hook. f., was confirmed the protective effect on liver injury in our previous study. This research aimed to investigate the protective mechanism of BPS on experimental liver injury by attenuating cell ferroptosis through modulating solute carrier family 7 member 11/glutathione peroxidase 4 (SLC7A11/GPX4) pathway. The animal experiment was approved by the Experimental Animal Ethical Committee of Hubei Minzu University and all rats had received human care in compliance with the institutional animal care guidelines. Rats were given intraperitoneal injection of (D-galactosamine, D-GalN) solution (800 mg·kg^-1) one time to establish the acute liver injury model. The results showed aspartate amino transferase (AST), alanine aminotransferase (ALT) and 4-hydroxynonenal (4-HNE) levels in serum were decreased, and the contents of reactive oxygen species (ROS), Fe²⁺, malondialdehyde (MDA) and lipid peroxide (LPO) in liver tissues also decreased and glutathione (GSH) level increased after BPS administration with 200 mg·kg^-1. Besides, BPS reduced iron deposition and increased the expression of SLC7A11 and GPX4 proteins in liver tissue. In conclusion, BPS ameliorated experimental liver injury by alleviating cell ferroptosis through SLC7A11/GPX4 pathway. The present study pointed to the possibility of utilizing BPS for protection against liver injury in clinic.

Fourteen compounds were isolated from the ethyl acetate fraction of 90% EtOH extracts of the dried fruits of Alpinia oxyphylla by silica gel, MCI, RP-18, Sephadex LH-20, TLC and semi-preparative HPLC column chromatography. Their structures were identified by HR-ESI-MS, UV, IR, NMR, ECD and X ray single crystal diffraction spectroscopic data as: (2R, 5R, 7R, 10S)-2, 7-dihydroxyl-eudesmane-3(4), 11(12)-diene (1), α-rotunol (2), diketone I (3), (1S, 4S, 5R, 7S)-1-hydroxyl-eremophilane-9(10), 11(12)-diene-8-one (4), cyperusol A₁ (5), (6R, 9S, 10S)-10-hydroxyl-11, 12, 13-trinor-cadinane-4(5)-ene-3-one (6), (2E, 4E)-6-hydroxy-2, 6-dimethylhepta-2, 4-dienal (7), oxyphyllacinol (8), yakuchinone A (9), (5R)-5-hydroxy-1, 7-diphenylhept-3-heptanone (10), (5S)-5-hydroxy-7-(4″-hydroxyphenyl)-1-phenylhept-3-heptanone (11), (5S)-5-hydroxy-7-(4″-hydroxyl-3″-methoxyphenyl)-1-phenyl-3-heptanone (12), 7-(4″-hydroxy-3″-methoxyphenyl)-1-phenyl-3, 5-heptadione (13), bis-(2-ethylhexyl) terephthalate (14). Compounds 1-6 were sesquiterpenoids in which compound 1 is a new eudesmane sesquiterpenoid and compound 7 was a monoterpenoid. Compounds 8-13 were diarylheptanoids, and compounds 2-6 and 14 were isolated from A.oxyphylla for the first time. The experiments on H₂O₂ induced SH-SY5Y cells showed that compounds 2, 6, 7, 12 and 13 had neuroprotective effects at low and medium concentrations. In particular, compound 6 showed obvious neuroprotective effect at low, medium and high concentrations whose cell viability was higher than that of the positive control.

3D printing is an additive manufacturing technology with the help of digital control. Since FDA approved the first 3D printing drug in 2015, its research enthusiasm in the pharmaceutical field has been increasing year by year. In printing technology, fused deposition molding (FDM) and semi-solid extrusion (SSE) are the two most widely used extrusion molding technologies. In this review, recent advances of pharmaceutical 3D printing extrusion molding technology are reviewed from six aspects: mechanism, equipment, pharmaceutical excipients, applications, design and industrialization prospects of extrusion molding technology.

Salvia miltiorrhiza Bunge is a traditional Chinese medicinal herb widely used to treat cardiovascular and cerebrovascular diseases at clinic. Its main water-soluble components are rosmarinic acid (RA) and salvianolic acid B (SAB), which are produced by phenylpropanoid pathway. 4-Hydroxyphenylpyruvate reductase (HPPR) is a key enzyme in phenylpropanoid metabolism pathway. SmHPPR1 was cloned from S. miltiorrhiza and was constructed into plant expression vector pJR-SmHPPR1. On this basis, SmHPPR1 transgenic Arabidopsis plants were induced and the content of 4-hydroxyphenyllactic acid (pHPL) was determined. SmHPPR1-overexpressing (SmHPPR1-OE) hairy roots of S. miltiorrhiza were obtained and the concentration of active components and transcriptome analysis were performed. The results showed that the concentration of pHPL in SmHPPR1 transgenic Arabidopsis T1 was 0.594 mg·g^-1 dry weight. The concentration of RA, SAB and total salvianolic acid in SmHPPR1-OE-3 hairy roots were 1.09, 1.29, 1.15 times of that in control-3, respectively, and the content of Danshensu was 36.26% of that in control-3. Transcriptomic analysis revealed that overexpression of SmHPPR1 caused the upregulation of other phenylpropanoid pathway genes like SmTAT2. Protein-protein interaction indicated CYT (TR74706_c0_g1), NADP⁺ (TR26565_c0_g1) and NADP⁺ (TR68771_c0_g1) is the central node of the network and participated in metabolic process and cellular process. The tracking work in this study proved that SmHPPR1 could catalyze the reduction of 4-hydroxyphenylpyruvic acid to 4-hydroxyphenyllactic acid in SmHPPR1 transgenic Arabidopsis, and SmHPPR1-overexpressing in hairy roots of S. miltiorrhiza could increase the concentration of salvianolic acids through synergistically regulating other pathway genes.

A quantitative analysis of multi-components by single marker method (QAMS) was established for simultaneous determination of gallic acid, protocatechuic acid, catechin, epicatechin, p-coumaric acid, ferulic acid and phloridzin in Cynomorium songaricum Rupr. The analysis was performed on a ChromCore Polae C₁₈ column (250 mm×4.6 mm, 5 μm), with a mobile phase consisting of acetonitrile-0.3% phosphoric acid aqueous solution for gradient elution. The volume flow rate, column temperature and sample injection volume were set at 1.0 mL·min^-1, 25 ℃, and 40 µL, respectively. The relative correction factors of gallic acid and protocatechuic acid, catechin, epicatechin, p-coumaric acid, ferulic acid and phloridzin were calculated and the durability was also investigated. The contents of these seven compounds in fourteen batches of Cynomorium songaricum Rupr. from different producing areas or batches were determined by external standard method (ESM) and quantitative analysis of multi-components with a single-marker method (QAMS), respectively. SPSS and Origin Pro software were employed for principal components assay, similarity evaluation and cluster analysis. The specificity, precision, repeatability, stability and linear range (R² > 0.999 0) of the seven components were all good. The average recovery was 96.89%-103.16% and RSD was 0.55%-2.76%. Then gallic acid was chosen as internal reference for calculation the correction factors for the other six components, the average relative correction factors of protocatechuic acid, catechin, epicatechin, p-coumaric acid, ferulic acid and phloridzin were 1.141 5, 0.200 5, 0.208 0, 2.361 9, 1.867 7, 0.204 6, respectively. Student's test results showed that there was no significant difference between the data analyzed by ESM and the data obtained from QAMS method. Through data visualization analysis, the contents of gallic acid, protocatechuic acid, catechin and epicatechin in different samples were significantly different, indicating that these four components might be the main quality markers of Cynomorium songaricum Rupr. for gaving more contributes to the principal components. The cluster analysis showed that samples from Xinjiang and samples from Inner Mongolia were clustered in significantly different categories, meaning that the quality of Cynomorium songaricum Rupr. had great relation with producing areas. The method of QAMS established in this study is a simple, economical and practical method with scientific and applicable charactistics for evaluating the quality of Cynomorium songaricum Rupr. efficiently and scientifically.

With the growing demand of personalized medicine for children, it is especially important to develop medicines for children. In this study, using metoprolol tartrate as model drug, we developed 3D printed chewable tablets suitable for children with automated dosage distribution using semi-solid extruded (SSE) 3D printing technology. Based on the quality by design concept, this study prepared a semi-solid material with good printability using gelatin as the substrate, constructed 3D models and printed tablets with the aid of computer-aided design. The printing parameters were optimized and determined as follows: print temperature of 35-37 ℃, print speed of 25 mm·s^-1, fill rate of 15%, and number of outer profile layers of 2. Subsequently, the printing process and the quality uniformity of the tablets were verified, and a linear relationship between the dose and the number of model layers was obtained. Finally, 3D printed chewable tablets were superior in terms of appearance, dose accuracy and compliance compared with traditional split-dose commercially available tablets. In this study, 3D printed metoprolol tartrate chewable tablets with good performance were successfully prepared to address the personalized medication needs of pediatric patients.

As a common protease with high similarity among coronavirus species, the main protease (M^pro) of SARS-CoV-2 is responsible for the catalytic hydrolysis of viral precursor proteins into functional proteins, which is essential for coronavirus replication and is one of the ideal targets for the development of broad-spectrum antiviral drugs. This paper reviews the main protease inhibitors of SARS-CoV-2, including their molecular structures, potencies and drug-like profiles, binding modes and structure-activity relationships, etc.

In this study, ultra performance liquid chromatography-quadrupole-time of flight mass spectrometer-MS^E (UPLC-Q-TOF-MS^E) combined with UNIFI analysis platform was used to rapidly analyze and identify the metabolites of hederagenins 3-O-α-L-rhamnosyl-(1→2)-[β-D-glucopyranosyl-(1→4)]-α-L-arabopyranoside (Pulsatilla saponin D) and oleanolic acid 3-O-α-L-rhamnosyl-(1→2)-[β-D-glucopyranosyl-(1→4)]-α-L-arabopyranoside (Pulsatilla saponin B₇) and hederagenins 3-O-α-L-rhamnosyl-(1→2)-α-L-arabopyranoside (Pulsatilla saponin BD) in plasma and colonic tissue of normal and ulcerative colitis (UC) rats. The database and analysis methods were established based on the precise molecular weight of compounds, retention time, neutral loss and reported data, and then the final data were obtained by comparing with the blank control group, combining with the deviation and the cracking rule of the compound. The results showed that the glucoses, hydroxylation and dehydroxylation, methylation and demethylation, dehydrogenation, decarboxylation and hydrolysis of saponin D, B₇ and BD occurred in the plasma and colon tissues of normal and UC model rats. This study will clarify the metabolic transformation of Pulsatilla saponins D, B₇ and BD in rats, determine the prototype components and their metabolites that enter the body, and whether colon injury will affect their metabolism in vivo, so as to explore the possible anti-colitis effective components in the prototype or metabolites of Pulsatilla saponins D, B₇ and BD. This experiment was approved by Animal Ethics Committee of Jiangxi Science and Technology Normal University (approval number: Y202227).