Due to patient compliance and convenience, oral medication is likely the most common and acceptable method of drug administration. However, traditional dosage forms such as tablets or capsules may lead to low drug bioavailability and poor therapeutic efficiency. Therefore, with advancements in material science and micro/nano manufacturing technology, various carriers have been developed to enhance drug absorption in the gastrointestinal tract. In this context, we initially discuss the key biological factors that hinder drug transport and absorption (including anatomical, physical, and biological factors). Building on this foundation, recent progress in both conventional and innovative oral drug delivery routes aimed at improving drug bioavailability and targeting is reviewed. Finally, we explore future prospects for oral drug delivery systems as well as potential challenges in clinical translation.

In order to explore the possible role and molecular mechanism of the combined action of leech and bear bile in liver and gallbladder diseases, this study first used network pharmacology methods to screen the components and targets of leech and bear bile, as well as the related target genes of liver and gallbladder diseases. The selected key genes were subjected to interaction network and GO/KEGG enrichment analysis. Then, using sodium oleate induced HepG2 cell lipid deposition model and DL-ethionine induced mouse fatty liver model, the activity of leech and bear bile alone and in combination in reducing liver fat was evaluated in vitro and in vivo, and the expression of key pathway related proteins suggested by network pharmacology was detected by Western blot. The results of network pharmacology analysis showed that the active ingredients of leech and bear bile have 295 intersecting targets with liver and gallbladder related diseases, involving more than 200 signaling pathways, including the PI3K/Akt signaling pathway and phospholipase D signaling pathway closely related to glucose and lipid metabolism. The results of in vitro validation experiments showed that both leech and bear bile, alone and in combination, can significantly inhibit the lipid deposition induced by sodium oleate in human liver cells, reduce the triacylglycerol level in cell culture supernatant, and inhibit the lipid content in liver cells. The observation results of Nile red staining confocal microscopy showed that the combination of leech and bear bile had better activity in reducing lipid deposition in liver cells compared to using them alone. In a mouse fatty liver model, the combination of leech and bear bile can better reduce elevated organ indices, blood lipids, and liver lipid levels, as well as lower the levels of serum liver injury biomarkers. The animals used in this experiment and related disposal meet the requirements of animal welfare. Before the experiment, it was reviewed and approved by IACUC, Institute of Materia Medica, Chinese Academy of Medical Sciences. The Western blot experiment results showed that the combination of leech and bear bile can significantly upregulate the expression levels of p-PI3K and p-Akt proteins, and increase the p-PI3K/PI3K and p-Akt/Akt ratios, which is consistent with the predicted results of network pharmacology. The combination of leech and bear bile has great potential for treating fatty liver disease, and activating the PI3K/Akt pathway may be one of the important mechanisms for reducing lipid deposition in liver cells.

Metabolic-associated fatty liver disease (MAFLD) and osteoporosis (OP) are two very common metabolic diseases. A growing body of experimental evidence supports a pathophysiological link between MAFLD and OP. MAFLD is often associated with the development of OP. Rutaecarpine (RUT) is one of the main active components of Chinese medicine Euodiae Fructus. Our previous studies have demonstrated that RUT has lipid-lowering, anti-inflammatory and anti-atherosclerotic effects, and can improve the OP of rats. However, whether RUT can improve both fatty liver and OP symptoms of MAFLD mice at the same time remains to be investigated. In this study, we used C57BL/6 mice fed a high-fat diet (HFD) for 4 months to construct a MAFLD model, and gave the mice a low dose (5 mg·kg^-1) and a high dose (15 mg·kg^-1) of RUT by gavage for 4 weeks. The effects of RUT on liver steatosis and bone metabolism were then evaluated at the end of the experiment [this experiment was approved by the Experimental Animal Ethics Committee of Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences (approval number: IMB-20190124D₃03)]. The results showed that RUT treatment significantly reduced hepatic steatosis and lipid accumulation, and significantly reduced bone loss and promoted bone formation. In summary, this study shows that RUT has an effect of improving fatty liver and OP in MAFLD mice.

Coronary restenosis is an important cause of poor long-term prognosis in patients with coronary heart disease. Here, we show that lysine methyltransferase SMYD2 expression in the nucleus is significantly elevated in serum- and PDGF-BB-induced vascular smooth muscle cells (VSMCs), and in tissues of carotid artery injury-induced neointimal hyperplasia. Smyd2 overexpression in VSMCs (Smyd2-vTg) facilitates, but treatment with its specific inhibitor LLY-507 or SMYD2 knockdown significantly inhibits VSMC phenotypic switching and carotid artery injury-induced neointima formation in mice. Transcriptome sequencing revealed that SMYD2 knockdown represses the expression of serum response factor (SRF) target genes and that SRF overexpression largely reverses the inhibitory effect of SMYD2 knockdown on VSMC proliferation. HDAC3 directly interacts with and deacetylates SRF, which enhances SRF transcriptional activity in VSMCs. Moreover, SMYD2 promotes HDAC3 expression via tri-methylation of H3K36 at its promoter. RGFP966, a specific inhibitor of HDAC3, not only counteracts the pro-proliferation effect of SMYD2 overexpression on VSMCs, but also inhibits carotid artery injury-induced neointima formation in mice. HDAC3 partially abolishes the inhibitory effect of SMYD2 knockdown on VSMC proliferation in a deacetylase activity-dependent manner. Our results reveal that the SMYD2-HDAC3-SRF axis constitutes a novel and critical epigenetic mechanism that regulates VSMC phenotypic switching and neointimal hyperplasia.

Esophageal cancer （EC） is a common malignant tumor of the digestive system with an extremely poor prognosis. MicroRNA （miRNA） is an important regulator in tumor occurrence and development， and can participate in malignant biological behaviors such as tumor cell proliferation， invasion， metastasis and apoptosis. Traditional Chinese medicine has the characteristics of accurate curative effects， wide range of effects， and few side effects. The review uses miRNA as the entry point to systematically elaborate on the mechanism of traditional Chinese medicine-mediated miRNA intervening in EC. The results showed that active ingredients of traditional Chinese medicine （including curcumin， Tussilago farfara polysaccharides， Atractylodes macrocephala polysaccharides and ophiopogonin B） and Dougen guanshitong oral liquid could up-regulate the expressions of miRNAs such as miRNA-532-3p （miR-532-3p）， miR-551b-3p， miR-99a， miR-34a， miR-199a-3p and miR-377； and the active ingredients/parts of traditional Chinese medicine （including chrysin and Actinidia arguta extract）， and Chinese herbal formulas （including Chaihu shugan san combined with Xuanfu daizhe decoction and Modified jupi zhuru decoction） could down-regulate the expressions of miRNAs such as miR-199a-3p， miR-451 and miR-21， which could regulate the expressions of signaling pathways （phosphoinositide 3-kinase/protein kinase B， etc.） or their downstream protein（zinc-finger and homeobox protein 1， etc.） or enzymes（thymidine kinase-1， etc.）， inhibit the proliferation， invasion and metastasis of EC cells and induce apoptosis， thereby ultimately achieving the purpose of preventing the disease from aggravating.

Four pyrazines were isolated from the n-butanol fraction of Hypecoum erectum L. by using various chromatographic methods, including MCI gel, ODS, silica gel and semi-preparative HPLC. The structures of the isolated compounds were identified as hyperectpyrazin A (1), 1′S-(6-methylpyrazin-2-yl)-ethane-1′,2′-diol (2), 2-hydroxymethyl-6-methylpyrazin (3) and pyrazine-2-carboxylic acid (4) by spectroscopy methods (1D NMR, 2D NMR, UV, IR, MS, etc.). The absolute configuration of compound 2 was determined by using the Mo₂(OAc)₄ induced CD analysis for the first time. Compound 1 was a new compound, compounds 2-4 were isolated from H. erectum for the first time. Compounds 1-4 were evaluated for their inhibition against acetylcholinesterase and nitric oxide generation induced by lipopolysaccharide-RAW264.7 macrophage cells. At a concentration of 50 μmol·L^-1, compounds 2 and 4 displayed inhibitory effects on acetylcholinesterase with the inhibition rates of 44.40% and 43.99%, respectively.

Platycodonis Radix is the dry root of Platycodon grandiflorum of Campanulaceae, which has a variety of pharmacological effects and is a commonly used bulk Chinese medicine. In this study, the chloroplast genome sequences of six P. grandiflorum from different producing areas has been sequenced with Illumina HiSeq X Ten platform. The specific DNA barcodes were screened, and the germplasm resources and genetic diversity were analyzed according to the specific barcodes. The total length of the chloroplast genome of 6 P. grandiflorum samples was 172 260-172 275 bp, and all chloroplast genomes showed a typical circular tetrad structure and encoded 141 genes. The comparative genomics analysis and results of amplification efficiency demonstrated that trnG-UCC and ndhG_ndhF were the potential specific DNA barcodes for identification the germplasm resources of P. grandiflorum. A total of 305 P. grandiflorum samples were collected from 15 production areas in 9 provinces, for which the fragments of trnG-UCC and ndhG_ndhF were amplificated and the sequences were analyzed. The results showed that trnG-UCC and ndhG_ndhF have 5 and 11 mutation sites, respectively, and 5 and 7 haplotypes were identified, respectively. The combined analysis of the two sequences formed 13 haplotypes (named Hap1-Hap13), and Hap4 is the main genotype, followed by Hap1. The unique haplotypes possessed by the three producing areas can be used as DNA molecular tags in this area to distinguish from the germplasm resources of P. grandiflorum from other areas. The haplotype diversity, nucleotide diversity and genetic distance were 0.94, 4.79×10^-3 and 0.000 0-0.020 3, respectively, suggesting that the genetic diversity was abundant and intraspecific kinship was relatively close. This study laid a foundation for the identification of P. grandiflorum, the protection and utilization of germplasm resources, and molecular breeding.

Reflux esophagitis is an inflammatory disease of esophageal mucosa damage caused by the reflux of gastric contents into the esophagus. Its incidence is on the rise， and it has become an important precancerous disease of esophageal cancer. Studies have shown that the continuous inflammatory response stimulates the esophageal mucosa， causing abnormal proliferation of esophageal epithelial cells and damage to esophageal mucosal tissue， which eventually leads to the occurrence of heterogeneous hyperplasia and even carcinogenesis. The nuclear transcription factor-kappa B （NF-κB） signaling pathway is one of the most classical inflammatory and cancer signaling pathways. It has been found that abnormal activation of the NF-κB signaling pathway is crucial to the development and prognosis of reflux esophagitis and esophageal cancer. It is widely involved in the proliferation， autophagy， apoptosis， and inflammatory response of esophageal epithelial cells and tumor cells， accelerating the transformation of reflux esophagitis to esophageal cancer and making it a potential target for the treatment of reflux esophagitis and esophageal cancer. Currently， there is no specific treatment for reflux esophagitis and esophageal cancer， and large side effects often appear. Therefore， finding a promising and safe drug remains a top priority. In recent years， traditional Chinese medicine scholars have conducted a lot of research on NF-κB signaling pathway， and the results indicate that NF-κB signaling pathway is an important potential target for traditional Chinese medicine to prevent and treat reflux esophagitis and esophageal cancer， but there is a lack of comprehensive and systematic elaboration. Therefore， this paper summarized the relevant studies in recent years， analyzed the relationship among NF-κB signaling pathway， reflux esophagitis， esophageal cancer， and transformation from inflammation to cancer， and reviewed the research literature on the regulation of the NF-κB signaling pathway in traditional Chinese medicine to prevent and treat reflux esophagitis and esophageal cancer， so as to provide new ideas for the prevention and treatment of reflux esophagitis and esophageal cancer.

Objective To evaluate the characteristics of different antigen-specific T cell immune responses to severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)after inoculation with 2 doses of SARS-CoV-2 inactivated vaccine for 12 months.Methods Fifteen healthy adults were enrolled in this study and blood samples collected at 12 months after receiving two doses of SARS-CoV-2 inactivated vaccine.The level and phenotypic characteristics of SARS-CoV-2 antigen-specific T lymphocytes were detected by activation-induced markers(AIM)based on polychromatic flow cytometry.Results After 12 months of inoculation with 2 doses of SARS-CoV-2 inactivated vaccine,more than 90%of adults had detectable Spike and Non-spike antigen-specific CD4+ T cells immune responses(Spike:14/15,P=0.0001;Non-spike:15/15,P<0.0001).80%of adults had detectable Spike and Non-spike antigen-specific CD8+ T cells immune responses(Spike:12/15,P=0.0463;Non-spike:12/15,P=0.0806).Antigen-specific CD4+ T cells induced by SARS-CoV-2 inactivated vaccination after 12 months were composed of predominantly central memory(CM)and effector memory 1(EM1)cells.On the other hand,in terms of helper subsets,antigen-specific CD4+ T cells mainly showed T helper 1/17(Th1/17)and T helper 2(Th2)phenotypes.Conclusions SARS-CoV-2 inactivated vaccination generates durable and extensive antigen-specific CD4+ T cell memory responses,which may be the key factor for the low proportion of severe coronavirus disease 2019(COVID-19)infection in China.

Objective To investigate the effect and mechanism of transplantation of neuregulin1(NRG1)gene-modified bone marrow mesenchymal stem cells(BMSCs)on the repair of hemi-transected spinal cord injury(SCI)in rats.Methods Isolated and cultured rat BMSCs,followed by transfection with the NRG1 gene.The levels of NRG1 in BMSCs lysate and culture supernatant was deected by ELISA method,and the proliferation activity of the BMSCs was detected by cell counting method.Forty-three healthy 8-week-old SD rats were randomly divided into control group(n=10),SCI model group(n=10),BMSCs group(n=10),and NRG1-BMSCs group(n=13).After establishing the spinal cord hemisection model,animals received in-situ transplantation of BMSCs or NRG1-BMSCs.On the 1,7,14,21,and 28 days after transplantation,the hind limb motor function was evaluated using BBB score and inclined plate test;on the 7th day after transplantation,the migration and distribution of transplanted cells was monitored using a fluorescence microscope;on the 28th day after transplantation,the pathological changes of rat spinal cord tissues was examined using HE staining and Nissl staining;cell apoptosis using TUNEL staining,and levels of endoplasmic reticulum stress-related proteins[X-box binding protein 1(XBP1),C/EBP homologous protein(CHOP),activating transcription factor 4(ATF4),ATF6,glucose-regulated protein 78(GRP78)]and apoptosis-related proteins[B-cell lymphoma-2(Bcl-2)and Bcl-2-associated protein X(Bax)]in rat spinal cord tissues using Western blotting.Results BMSCs were successfully isolated,cultured,and transfected with the NRG1 gene.ELISA method results showed that the NRG1 contents in the NRG1-BMSCs lysate and culture supernatant were significantly higher than that of BMSCs in a time-dependent manner(P<0.05).The proliferation activity of NRG1-BMSCs was significantly higher than that of BMSCs(P<0.05).On the 21 and 28 days after transplantation,the BBB score and the slope angle of the inclined plate in NRG1-BMSCs group were higher than those in SCI model group or BMSCs group(P<0.05).However,it did not reverse to the level in control group(P<0.05).On the 28th day after transplantation,compared with the SCI model group and BMSCs group,neuronal pyknosis reduced,the Nissl body density increased,the expression levels of XBP1,CHOP,ATF4,ATF6,GRP78,and Bax,and the rate of TUNEL-positive cells significantly reduced in NRG1-BMSCs group(P<0.05),and the expression level of Bcl-2 significantly increased(P<0.05).Conclusion Transplantation of NRG1 gene-modified BMSCs can alleviate SCI and improve the recovery of motor function in rats.The mechanism may be related to promoting the proliferation activity of BMSCs,inhibiting cell apoptosis,and mitigating endoplasmic reticulum stress.