ABSTRACT
Autophagy, as a highly conserved process of recovery and degradation of eukaryotic components, plays an important role in cell hunger response, maintenance of normal cell activity and specific functions in lung tissue. When cells are damaged due to physiological, pathological or chemical factors, autophagosomes and lysosomes fuse to produce a large number of autophagosomes, thus inducing the initiation of autophagy process, which is beneficial to protect cells from injury. Recent studies have found that autophagy related signaling pathways are highly correlated with the occurrence and development of a variety of viral pneumonia, such as swine influenza A (H1N1) virus, highly pathogenic avian influenza virus (H5N1), severe acute respiratory syndrome (SARS), middle east respiratory syndrome (MERS) and new coronavirus pneumonia (COVID-19). This paper will introduce the five viral pneumonia that have a great impact on China and even the whole world, and elaborate the mechanism of autophagy in these disease. Hopefully it could provide theoretical basis and effective methods and means for targeted autophagy treatment of viral pneumonia.
ABSTRACT
OBJECTIVE：To prepare cell penetrating peptide PFV-modified paclitaxel （PTX）/artesunate（ART）co-loaded targeting micelles ，and to investigate in vitro anti-tumor activity. METHODS ：According to optimal technology ，PFV-modified PTX/ ART co-loaded targeting micelles were prepared by membrane hydration method ，and were characterized. Using blank micelle as blank control ，sulforhodamine B （SRB）method was used to evaluate the toxicity of PTX micelles ，ART micelles ，PTX/ART micelles and PFV-modified PTX/ART co-loaded targeting micelles to human gastric cancer BGC- 823 cells. The coumarin was used as fluorescent probe replacing PTX to prepare corresponding micelles. Then ，the uptake of BGC- 823 cells to corresponding micelles and targeting effect were observed and determined by flow cytometry and fluorescence microscope. The effects of PTX micelles ， ART micelles ，PTX/ART micelles and PFV-modified PTX/ART co-loaded targeting micelles on the invasion of BGC- 823 cells were investigated by Transwell chamber method. RESULTS ：Average particle size of PFV-modified PTX/ART co-loaded targeting micelles was （51.30±3.95）nm；PDI was 0.19±0.01，and Zeta potential was （0.21±0.02）mV. The encapsulation efficiency of PTX and ART were higher than 90％. The shape of micelles were spherical. The blank micelles had no obvious toxicity to BGC-823 cells. The IC 50 value of PTX micelles ，PTX/ART micelles and PFV-modified PTX/ART co-loaded targeting micelles to BGC-823 cells were （3.09±0.22），（1.93±0.24），（1.11±0.15）μmol/L，respectively. The distribution amount of different micelles in BGC- 823 cell nucleus in the descending order were PFV-modified coumarin/ART micelles ＞coumarin/ART micelles ＞coumarin micelles＞blank control. The order of inhibitory effect was PFV-modified PTX/ART co-loaded targeting micelles ＞PTX/ART micelles＞ART micelles ＞PTX micelles ＞blank control. CONCLUSIONS： Prepared PFV-modified PTX/ART No.81874347） co-loaded targeting micelles are in line with the quality of 1915286446@qq.com Chinese Pharmacopoeia . It shows strong cytotoxicity to BGC-823 cells，can improve the drug targeting and the cell uptake，and inhibit the inv asion and metastasis of BGC- 823 cells.
ABSTRACT
Objective To prepare asiaticoside-loaded modified liposomes and to investigate the distribution and pharmacokinetics. Methods Different asiaticoside-loaded preparations (include solution, modified, and unmodified liposomes) were injected by tail vein in SD rats. HPLC method was used to detect the concentration of asiaticoside in the tissue and plasma samples. And the concentration-time profiles and pharmacokinetic parameters were then obtained and compared to get the variances. Results The concentration-time profiles of asiaticoside-loaded preparations guided along the single compartment model which the weight is 1/C2. The elimination half-life of asiaticoside solution and different asiaticoside liposomes were (14.52 ± 0.56), (101.35 ± 12.47), (149.82 ± 20.00), and (159.58 ± 16.46) min, respectively. The AUC of asiaticoside solution and different asiaticoside liposomes were (1 929.70 ± 159.00), (57 004.35 ± 8 710.89), (93 736.52 ± 12 710.76), and (64 737.48 ± 6 365.28) min∙μg/mL, respectively. The mass fraction of asiaticoside in each organ increased, especially in the pulmonary which increased from (4.94 ± 0.94) μg/g to (39.12 ± 12.04) μg/g. Conclusion The sustained release and targeting effects in SD rats were obvious of the asiaticoside-loaded modified liposomes.